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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to signal line driving circuits for providing output signals with approximately constant output currents, and in particular, to subscriber line interface circuits for telephone lines.
2. Description of the Related Art
A subscriber line interface circuit (SLIC) is used for each pair of wires (“tip” and “ring”) forming a subscriber telephone line and is responsible for conveying both incoming and outgoing signals (e.g., voice, facsimile and data) while providing necessary power and impedance matching. Such circuit is typically located in the central office and is analog in its function, although digital versions (e.g., ISDN) are being used more often.
When the subscriber telephone is on-hook the DC output current, neglecting any leakage impedances, is substantially zero. When the subscriber loop goes into an off-hook state, industry standards require a DC output current through the subscriber loop to be approximately constant, e.g., within the nominal range of 30-40 milliamperes (mA). This DC current provides power to the subscriber telephone circuitry, such as the digital keypad. The impedance of the subscriber loop will depend upon the particular telephone, or telephones, connected to the loop, as well as the transmission length of the loop itself. Therefore, the SLIC must be designed to provide the nominal required DC output current for this range of loop impedances while still providing for transmission of the AC signals (voice, facsimile, etc.).
Based upon the foregoing, the following typical scenarios will be encountered. With an output current of 30 mA, a nominal DC power supply voltage of 50 volts for the SLIC, and a subscriber loop impedance of 1000 ohms (resistive), the output voltage presented to the subscriber loop will be 30 volts (=30 mA×1000 ohms). Accordingly, 20 volts will be dropped across the SLIC output circuitry, thereby resulting in approximately 0.6 watts (=30 mA×20 volts) of power dissipation in the output circuitry of the SLIC. However, if the subscriber loop impedance is instead only 500 ohms, then the output voltage becomes 15 volts (=30 mA×500 ohms). This results in 35 volts being dropped across the output circuitry of the SLIC, which, in turn, results in an internal power dissipation of approximately 1.05 watts (=30 mA×35 volts). Hence, it can be seen that, depending upon the subscriber loop impedance, a wide variance in the internal power dissipation of the SLIC can be encountered. Such a wide variance in internal power dissipation imposes substantial design constraints for the SLIC, and prevents such SLIC from performing at maximum efficiency.
A number of attempts to minimize the internal power dissipation of the SLIC have included such techniques as using an external resistor (connected in series with the power supply) for dissipating the excess power and using a switching voltage regulator. However, both techniques have significant disadvantages. Simply relocating the power dissipation to an external resistor does not improve overall efficiency of the system, and while a switching voltage regulator may improve power efficiency, significant switching noise can be induced into the subscriber loop.
Accordingly, it would be desirable to have a technique by which internal power dissipation can be automatically reduced by maximizing power efficiency and avoiding any introduction of signal noise.
SUMMARY OF THE INVENTION
A signal line driving circuit with self-controlled internal power dissipation in accordance with the present invention minimizes internal power dissipation while maximizing overall power efficiency and avoiding introduction of extraneous signal noise into the system.
In accordance with one embodiment of the present invention, a signal line driving circuit with power control for selectively reducing internal power dissipation when driving an external load includes a signal driver circuit and a power control circuit. The signal driver circuit is configured to connect and provide an output signal to an external impedance and to receive a source current and an input signal which corresponds to such output signal and in accordance therewith provide such output signal and a control signal which varies in relation to such output signal. The output signal includes an output current which is approximately constant and an output voltage which varies in relation to the external impedance and output current. The power control circuit, coupled to the signal driver circuit, is configured to connect to a plurality of voltage sources and receive therefrom a plurality of source voltages and to receive the control signal and in accordance therewith convey the source current from one of the plurality of voltage sources to the signal driver circuit.
In accordance with another embodiment of the present invention, a method of driving an external load via a signal line while selectively reducing power dissipation includes the steps of:
connecting to an external impedance;
connecting to a plurality of voltage sources;
applying an output signal to the external impedance;
receiving a source current and an input signal which corresponds to the output signal and in accordance therewith generating the output signal and a control signal which varies in relation to the output signal, wherein the output signal includes an output current which is approximately constant and an output voltage which varies in relation to the external impedance and the output current;
receiving a plurality of source voltages from the voltage sources; and
receiving the control signal and in accordance therewith conveying the source current from one of the plurality of voltage sources.
These and other features and advantages of the present invention will be understood upon consideration of the following detailed description of the invention and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a functional block diagram of a signal interface system using a signal line driving circuit with self-controlled internal power dissipation in accordance with one embodiment of the present invention.
FIG. 2 is a more detailed functional block and schematic diagram of the signal line driving circuit portion of the system of FIG. 1 .
DETAILED DESCRIPTION OF THE INVENTION
(While the following discussion is in the context of a subscriber line interface circuit (SLIC) for telephone signals, it should be recognized that the underlying principles of the present invention can be applied to other forms of circuits which provide output signals with substantially constant currents and for which self-control of internal power dissipation is desired.)
Referring to FIG. 1, a bi-directional signal interface system 10 using a signal line driving circuit with self-controlled internal power dissipation in accordance with one embodiment of the present invention includes a driver stage 12 , a receiver stage 14 , a power control stage 16 and multiple power sources 18 , interconnected substantially as shown. The driver stage 12 provides an output signal 13 to an output node 20 for conveyance to an external signal line 22 . The output node 20 also conveys from the external signal line 22 an input signal 21 which is processed by the receiver 14 . The output signal 15 from the receiver 14 is fed back to the driver stage 12 . As is well known in the art of SLICs, this allows for duplex operation of the external signal line 22 by subtracting out the receiver output signal 15 from the input signal 11 to the driver stage 12 .
The driver stage 12 provides a feedback signal 17 a to the power control stage 16 which provides DC power 17 b to the driver stage 12 . Based upon the feedback signal 17 a, the power control stage 16 selects one of multiple DC voltages 19 from the DC power sources 18 . For example, when the load impedance presented via the external signal line 22 is low, based upon the output signal 13 current, the output voltage presented to the output node 20 is low. When this output voltage becomes low enough that the resulting voltage drop across the output of the driver stage 12 (Vdriver=Vsource−Voutput) exceeds a predetermined threshold (Vdriver>Vthreshold), the feedback signal 17 a can instruct the power control stage 16 to select a lower power supply voltage 19 from another power source 18 (discussed in more detail below).
Referring to FIG. 2, the driver 12 and power control 16 stages in accordance with one embodiment of the present invention are shown in more detail. In this embodiment, as would be typical for a SLIC, the external circuit is a differential circuit. Accordingly, the output node 20 includes two nodes 20 a, 20 b and the external signal line 22 includes two lines 22 a, 22 b. In the context of a SLIC, these two signal lines 22 a, 22 b form the subscriber loop.
The driver stage 12 includes a transconductance stage 30 which differentially receives the input voltage signals 11 , 15 and generates two intermediate current signals 31 a, 31 b which are buffered by output driver amplifiers 32 a, 32 b. These amplifiers 32 a, 32 b provide the approximately constant output current signals 13 a, 13 b (discussed in more detail below) to the output nodes 20 a, 20 b. (As discussed above, the output nodes 20 a, 20 b also receive the incoming signals 21 a, 21 b from the subscriber loop 22 a, 22 b which are processed by the receiver 14 in accordance with well known principles.) These amplifiers 32 a, 32 b are powered by positive and negative power sources. The positive power source V+ is typically zero for telecommunications applications. The negative power source V− is a negative supply.
The power control stage 16 includes a differential amplifier 40 which drives a pass transistor connected between a diode 44 a and the primary power source 18 a which provides a negative power supply voltage Vbat. The input signal to the differential amplifier 40 , which is the feedback, or control, signal 17 a from the transconductance stage 30 , is filtered by a low pass filter formed by the series resistor 46 (e.g., 500 kilohms) and shunt capacitor 48 (e.g., 220 nanofarads). Connected across the resistor 46 is a “speed up” circuit 50 which, as discussed in more detail below, selectively reduces the overall resistance so as to speed up the change in the voltage across the capacitor 48 .
Another diode 44 b is used to connect another power source 18 b having another negative voltage Vbatr to the same node 17 c as that to which the first diode 44 a is connected. It is this node 17 c which provides the negative power supply voltage 17 b for the output driver amplifiers 32 a, 32 b. The first power supply voltage Vbat is the more negative voltage (e.g., −56 volts), while the second power supply voltage Vbatr is a less negative voltage (e.g., −30 volts).
As the impedance of the subscriber loop 22 a, 22 b reduces, such as when the subscriber goes off-hook, the differential voltage Vab at the loop nodes 20 a, 20 b also decreases. This voltage Vab is sensed by the receiver 14 (which typically has a high input impedance relative to the impedance of the subscriber loop and the output impedances of the driver amplifiers 32 a, 32 b ). Accordingly, the receiver output voltage 15 , which corresponds to the subscriber loop node voltage Vab, also decreases. This, in turn, causes the control voltage 17 a from the transconductance stage 30 to also decrease. This control voltage 17 a is generally proportional to the receiver output voltage 15 (which in turn, is generally proportional to the subscriber loop node voltage Vab), plus some amount of overhead voltage Voh necessary for the driver amplifiers 32 a, 32 b to operate.
As this voltage 17 a decreases further, the differential amplifier 40 gradually causes the pass transistor 42 to turn off. If the control voltage 17 a decreases sufficiently, the transistor 42 becomes cut off and the supply current for the negative supply terminals of the driver amplifiers 32 a, 32 b is then drawn through the second diode 44 b from the second power supply 18 b instead of through the first diode 44 a from the first power supply 18 a. Since this second power supply 18 b has a reduced voltage Vbatr, the voltage dropped across the driver amplifiers 32 a, 32 b is reduced, thereby reducing the internal power dissipation of the driver amplifiers 32 a, 32 b. Since the output current 13 a, 13 b is maintained approximately constant, the signal provided to the subscriber is remains unaffected. Hence, the transition between power supply voltages is not dependent upon the actual voltage values of the power supplies 18 and occurs without introducing any signal noise.
As noted above, the output current signals 13 a, 13 b are approximately constant. More specifically, the output current signals 13 a, 13 b are approximately constant for a given impedance Zloop of the subscriber loop 22 a, 22 b. Hence, for example, if the impedance Zloop (e.g., the resistance Rloop) of the subscriber loop 22 a, 22 b increases (e.g., the loop becomes longer) and becomes less negligible with respect to the subscriber loop feed resistance Rfeed (e.g., 150 ohms) within the output circuits (not shown) of the driver amplifiers 32 a, 32 b, then the magnitude Iloop of the output current signals 13 a, 13 b will decrease in accordance with the relationship Iloop=(Vbat−Voh)/(Rloop+Rfeed). However, provided that the impedance Zloop of the subscriber loop 22 a, 22 b remains constant, the magnitude Iloop of the output current signals 13 a, 13 b will also remain constant.
Furthermore, it should be recognized that notwithstanding the similar directions of the arrows for the output current signals 13 a, 13 b in FIG. 2, the directions of such current signals 13 a, 13 b are opposite to one another. In other words, if output current 13 a is flowing out to subscriber loop leg 22 a via node 20 a, then output current 13 b is flowing in from subscriber loop leg 22 b via node 20 b, and vice versa.
During transient signals in the loop 22 a, 22 b, such as on/off-hook transient signals or dialling, the voltage provided to the loop nodes 20 a, 20 b must be allowed to slew quickly enough to avoid impacting the dial pulsed distortion parameters. This is achieved by shunting the resistor 46 in the input filter for the differential amplifier 40 . A transient detection circuit elsewhere in the system (not shown) generates a trigger signal 51 which closes a switch 52 within the speed of circuit 50 . This places a shunting resistor 54 in parallel with the original resistor 46 to reduce the overall resistance value by a sufficiently significant amount (e.g., by a factor of 100). This allows the circuit to reject speech signals during normal transmission and yet quickly slew in response to normal transient signals.
Based upon the foregoing, it should be recognized that although the power control stage 16 has been discussed in terms of switching between two power sources, it is possible to design another power control stage which, in conformance with the foregoing discussion, can select between more than two power sources. For example, by duplicating the combination of filter circuit 46 , 48 , differential amplifier 40 , transistor 42 and diode 44 a and connecting such duplicate circuits between other power sources having voltages with values intermediate to voltages Vbat and Vbatr, it is possible to provide for multiple stepped reductions in the power supply voltage provided to the driver amplifiers 32 a, 32 b. This would allow the power dissipation of the driver amplifiers 32 a, 32 b to be maintained within a fairly narrow power range.
Further based upon the foregoing, it should also be recognized that the principles of the presently claimed invention are not limited to use with circuits using negative power supplies or only bipolar technologies, but can also be applied to circuits using positive power supplies or other device technologies as well, such as metal oxide semiconductor (MOS).
Various other modifications and alterations in the structure and method of operation of this invention will be apparent to those skilled in the art without departing from the scope and spirit of the invention. Although the invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. It is intended that the following claims define the scope of the present invention and that structures and methods within the scope of these claims and their equivalents be covered thereby. | A signal line driving circuit with power control for selectively reducing internal power dissipation when driving an external load. While driving the external load with a constant current the output voltage generated across such load is monitored. If the load impedance decreases sufficiently to cause the output voltage to fall below a predetermined threshold value and, therefore, cause the voltage across the signal line driving circuit to increase, the magnitude of the power supply voltage is automatically reduced, thereby reducing the voltage across the signal line driving circuit. Such a signal line driving circuit is particularly advantageous as a subscriber line interface circuit (SLIC). As the subscriber goes from an on-hook condition to an off-hook condition and if the subscriber loop is sufficiently short (or low in impedance), a lower power supply voltage is used to minimize the power dissipation of the SLIC while still maintaining the required subscriber loop current. | 8 |
CLAIM OF PRIORITY
This application is a continuation of Ser. No. 14/107,535, filed on Dec. 16, 2013, which is a continuation of Ser. No. 13/480,376, filed on May 24, 2012, which is a divisional of U.S. Ser. No. 13/072,466, filed on Mar. 25, 2011, which is a divisional of U.S. Ser. No. 12/361,274, filed Jan. 28, 2009, which claims the benefit of prior U.S. Provisional Application No. 61/024,178, filed on Jan. 28, 2008, each of which is incorporated by reference in its entirety.
TECHNICAL FIELD
This description relates to controlled generation of nitric oxide.
BACKGROUND
Nitric oxide (NO), also known as nitrosyl radical, is a free radical that is an important signaling molecule in pulmonary vessels. Nitric oxide (NO) can moderate pulmonary hypertension caused by elevation of the pulmonary arterial pressure. Inhaling low concentrations of nitric oxide (NO), for example, in the range of 2-100 ppm can rapidly and safely decrease pulmonary hypertension in a mammal by vasodilation of pulmonary vessels.
Some disorders or physiological conditions can be mediated by inhalation of nitric oxide (NO). The use of low concentrations of inhaled nitric oxide (NO) can prevent, reverse, or limit the progression of disorders which can include, but are not limited to, acute pulmonary vasoconstriction, traumatic injury, aspiration or inhalation injury, fat embolism in the lung, acidosis, inflammation of the lung, adult respiratory distress syndrome, acute pulmonary edema, acute mountain sickness, post cardiac surgery acute pulmonary hypertension, persistent pulmonary hypertension of a newborn, perinatal aspiration syndrome, haline membrane disease, acute pulmonary thromboembolism, heparin-protamine reactions, sepsis, asthma and status asthmaticus or hypoxia. Nitric oxide (NO) can also be used to treat chronic pulmonary hypertension, bronchopulmonary dysplasia, chronic pulmonary thromboembolism and idiopathic or primary pulmonary hypertension or chronic hypoxia. Typically, the NO gas is supplied in a bottled gaseous form diluted in nitrogen gas (N 2 ). Great care has to be taken to prevent the presence of even trace amounts of oxygen (O 2 ) in the tank of NO gas because the NO, in the presence of O 2 , is oxidized to nitrogen dioxide (NO 2 ). Unlike NO, the part per million levels of NO 2 gas is highly toxic if inhaled and can form nitric and nitrous acid in the lungs.
SUMMARY
In one aspect, an apparatus for converting nitrogen dioxide to nitric oxide includes a receptacle including an inlet, an outlet, a surface-active material coated with an aqueous solution of ascorbic acid and an absorbent, wherein the inlet is configured to receive a gas flow and fluidly communicate the gas flow to the outlet through the surface-active material and the absorbent such that nitrogen dioxide in the gas flow is converted to nitric oxide. The absorbent can be silica gel or activated alumina.
In another aspect, a method of providing a therapeutic amount of nitric oxide to a mammal includes diffusing nitrogen dioxide into a gas flow, exposing the nitrogen dioxide to a surface-active material coated with ascorbic acid and an absorbent to eliminate the by-products of ascorbic acid oxidation and transporting the nitric oxide in a therapeutic amount to a mammal.
In a further aspect, a system of delivering a therapeutic amount of nitric oxide to a mammal includes a gas source of nitric oxide; and a NO 2 scavenger selected from the group consisting of proline and diphenylamine.
In one aspect, a recuperator for converting nitrogen dioxide into nitric oxide includes an exit shell including an outlet, an inside shell wherein the inside shell includes perforated inner and outer tubes with fixed annulus, a surface-active material coated with an aqueous solution of ascorbic acid, an absorbent and a top cap including an inlet wherein the inlet is configured to receive a gas flow and fluidly communicate the gas flow to the outlet through the surface-active material such that nitrogen dioxide in the gas flow is converted to nitric oxide. The recuperator further includes an annular ring around the top cap.
In another aspect, a system for delivering nitric oxide to a patient, includes a gas source of nitrogen dioxide, dinitrogen tetraoxide, or nitric oxide, a first device having an inlet, an outlet, and a porous solid matrix positioned between the inlet and the outlet, wherein the porous solid matrix is coated with an aqueous solution of an antioxidant, and wherein the inlet is configured to receive a gas flow from the source and fluidly communicate the gas flow to the outlet through the porous solid matrix to convert nitrogen dioxide in the gas flow into nitric oxide, and a recuperator coupled to the outlet of the first device, the recuperator converting nitrogen dioxide into nitric oxide prior to delivery to the patient. The recuperator can have a flow resistance of less than 3 cm of water pressure at a flow of 60 L/minute. The recuperator can have a flow resistance of less than 1 cm water at 15 L/min. The recuperator can operate at atmospheric pressure. The recuperator can have an oxygen concentration of in the range of 21 to 100%. The recuperator can have a humidity of dry to 99% (non condensing). The recuperator can be thermally insulated. The recuperator can be coupled to the outlet of a first device through a humidified line. The humidified line can be heated. The humidified line can be heated to about 35° C. The recuperator can be coupled to a NO/NO 2 gas analyzer. The recuperator can further include a particle filter.
In a further aspect, a method of sampling NO and NO 2 gas in a NO delivery system includes obtaining a sample of gas, diluting the sample of gas with air, and measuring the amount of NO and NO 2 gas with a gas analyzer. The sample of gas can be diluted by 50%. The sample of gas can be diluted by 33%. The sample of gas can be diluted with air from the hospital room. The sample of gas can be diluted with air from the wall. The sample of gas can be diluted with oxygen.
The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.
DESCRIPTION OF DRAWING
FIG. 1 is a block diagram of a cartridge that converts NO 2 to NO.
FIGS. 2A-B are diagrams depicting implementations of a disc filter recuperator.
FIGS. 3A-B are diagrams depicting implementations of a tubular filter recuperator.
FIG. 4 is a diagram depicting an implementation of a recuperator.
FIG. 5 is a diagram depicting another implementation of a recuperator.
FIGS. 6A and B are flow diagrams depicting Nitric Oxide (NO) delivery systems and flow of the gasses.
FIG. 7 is a graph depicting the variation of pressure drop with size of a disc recuperator.
FIG. 8 is a flow diagram depicting nitric oxide delivery for an intensive care unit.
FIGS. 9A-D are diagrams depicting geometrical depictions of dish filters and tube filters.
DETAILED DESCRIPTION
Nitric Oxide (NO) is very well known and well-studied gas. NO is normally present in the atmosphere (as a pollutant from automobiles and power plants) at concentrations between 0.010 and 0.500 parts per million (ppm), and NO concentrations may reach 1.5 ppm in heavy traffic. NO is also present in tobacco smoke at levels as high as 500 ppm to 2000 ppm.
For medical applications, NO gas, like oxygen has been studied and used to treat patients for many years. In biological systems, NO is a molecule that is naturally produced in the human body. NO is one of the few gaseous signaling molecules known. NO is a key vertebrate biological messenger, playing a role in a variety of biological processes. NO is highly reactive (having a lifetime of a few seconds), yet diffuses freely across membranes. These attributes make NO ideal for a transient signal molecule between adjacent cells and within cells. Several pharmaceutical products, such as Nitroglycerin, amyl nitrite and Sildenafil (Viagra) serve as vasodilators because they either release or cause NO to be released in the body. In 1987, the biologic similarities of NO to endothelium-derived relaxing factor were demonstrated. Subsequently, NO and endothelium-derived relaxing factor were considered the same entity. During the late 1980s and early 1990s, inhaled NO emerged as a potential therapy for the acute respiratory distress syndrome (ARDS), sickle cell anemia, COPD and other conditions. Since then NO has been shown to reduce persistent pulmonary hypertension and also to reduce pulmonary hypertension without any undesired drop in systemic blood pressure, which is valuable when treating heart and lung transplant patients and other patients having undergone interventional cardiovascular procedures. The gas was readily available for many years from several suppliers as were several competing CE marked delivery systems. During the 1990s the medical use of the gas was patented and the cost has increased substantially. Even with this restriction, NO is currently routinely and safely used under institutional or countywide protocols for many uses outside of the approved indications for neonates.
When delivering NO for therapeutic use to a mammal, it can be important to avoid delivery of nitrogen dioxide NO 2 to the mammal. NO 2 can be formed by the oxidation of NO with oxygen (O 2 ). The rate of formation of NO 2 is proportional to the O 2 concentration multiplied by the square of the NO concentration—that is, (O 2 )*(NO)*(NO)═NO 2 .
In one aspect, a NO delivery system that converts NO 2 to NO is provided. The system employs a surface-active material coated with an aqueous solution of antioxidant as a simple and effective mechanism for making the conversion. One example of a surface-active material is silica gel. Another example of a surface-active material that could be used is cotton. The surface-active material may be or may include a substrate capable of retaining water. Another type of surface-active material that has a large surface area that is capable of absorbing moisture also may be used. More particularly, NO 2 can be converted to NO by passing the dilute gaseous NO 2 over a surface-active material coated with an aqueous solution of antioxidant. When the aqueous antioxidant is ascorbic acid (that is, vitamin C), to the reaction is quantitative at ambient temperatures.
The oxidation of ascorbic acid with oxygen under moist conditions can be complex, with over 50 different compounds having been reported. (See J. C. Deutsch, “Spontaneous hydrolysis and dehydration of dehydroa.” Analytical Biochemistry, Vol. 260, no. 2, pages 223-229 (Jul. 1, 1998); Dong Bum Shin and Milton S. Feather, “3-deoxy-L-glycero-pentos-2-ulose (3-deoxy-L-xylosone) and L-threo-pentos-2-ulose (L-xylosone) as intermediates in the degradation of L-ascorbic acid,” Carbohydrate Research , Vol. 280, pages 246-250 (Dec. 15, 1990); Eiji Kimoto et al., “Analysis of the transformation products of dehydro-L-ascorbic acid by ion-pairing high-performance liquid chromatography,” Analytical Biochemistry , Vol. 214, pages 38-44 (1993), Academic Press; Steven R. Tannenbaum et al., “Inhibition of nitrosamine formation by ascorbic acid,” The American Journal of Clinical Nutrition , Vol. 53 (1 Suppl.) pages 247S-250S (January 1990), all of which are incorporated by reference in their entireties). The reaction generally leads to dehydroxy ascorbic acid, which can then be further degraded into multiple species.
FIG. 1 illustrates an example of a cartridge 100 for generating NO by converting NO 2 to NO. The cartridge 100 , which may be referred to as a NO generation cartridge, a cartridge, or a cylinder, includes an inlet 105 and an outlet 110 . Screen and glass wool 115 are located at both the inlet 105 and the outlet 110 , and the remainder of the cartridge 100 is filled with a surface-active material 120 that is soaked with a saturated solution of antioxidant in water to coat the surface-active material. The surface-active material can be silica gel. The screen and glass wool 115 also is soaked with the saturated solution of antioxidant in water before being inserted into the cartridge 100 . In the example of FIG. 1 , the antioxidant can include ascorbic acid. In other embodiments, the antioxidant can include alpha tocopherol or gamma tocopherol.
The moist silica gel of the cartridge can adsorb and bind up the vast majority of the products of the side reactions.
In the presence of moisture, oxygen and NO, NO 2 forms N 2 O 3 , N 2 O 4 and the nitrite ion. In one embodiment, these reactants can combine with an NO 2 scavenger which can include the common amino acid, proline, to form N-nitroso proline. N-nitrosproline is non carcinogenic. This reaction has been used in vivo by Tannenbaum The American Journal of Clinical Nutrition , Vol. 53 (1 Suppl.) pages 247S-250S (January 1990), and Ohshima and Bartsch ( Cancer Res . Vol. 41, p. 3658-3662 (1981), to measure the nitrosation capacity of the body, and to show that the addition of Vitamin C can reduce this capacity. Such a reaction can be used to trap out NO 2 in the gas phase from an air stream containing moist NO 2 in the presence of oxygen and NO. The proline can be in the form of a crystalline powder. Proline can be placed in a tube and gas can be allowed to flow over it. The NO 2 that is present can bind irreversibly with the proline to form N-nitroso proline. The application of this reaction is to use this reaction as a scavenger to remove the last minute traces of NO 2 from an air stream containing NO and oxygen and air. In one embodiment, such a NO 2 scavenger can be used in a NO delivery system to allow any NO 2 that is present to bind irreversibly with the proline to form N-nitroso proline.
The proline can be in the form of a powder, or as a solution that has been deposited onto a substrate such as silica gel, activated alumina and charcoal. Other appropriate substrates can be used as long as proline is available to react with NO 2 gas. In one embodiment, an aqueous solution of proline in water can be used. In another embodiment, diphenylamine or any secondary or tertiary amine can be used to react with NO 2 gas. Examples of secondary amines can include dimethylamine, methylethanolamine or 2-(methylamino)ethanol, cyclic amines such as aziridine, azetidine, pyrrolidine and piperidine. Examples of tertiary amine can include trimethylamine, dimethylethanolamine (DMEA), 2-(dimethylamino)ethanol or bis-tris.
Preferably, any material can be used where the Nitroso product will not be carcinogenic or toxic. In other embodiments, any compounds that hind with the NO 2 to form organic compounds can be used. Products include but are not limited to: nitro, nitroso, or azo as long as the NO 2 is chemically bound up so as to remove it from the system.
In one embodiment, an NO 2 scavenger can be included in a NO delivery system. The purpose of the NO 2 scavenger is to remove any NO 2 gas that may have been formed in the ventilator and during storage in a gas bag or other temporary gas storage device. In another embodiment, the NO 2 scavenger can remove NO 2 that is formed in the gas plumbing lines from the exit of the NO generation cartridge. The NO 2 scavenger can serve as a safety device to reduce the NO 2 levels to below 0.1 ppm, at any flow and at any NO concentration, prior to delivery to a patient.
In another aspect, a recuperator is included in the NO delivery system. The purpose of the recuperator is to convert any NO 2 gas that may have been formed in the ventilator and to during storage in a gas bag or other temporary gas storage device to NO. In one embodiment, the recuperator is a device that is immediately adjacent to the patient. It serves the same purpose as the main NO generation cartridge, namely to convert NO 2 to NO. In another embodiment, the recuperator coverts NO 2 that is formed in the gas plumbing lines from the exit of the cylinder NO generation cartridge to NO. The recuperator can be a cartridge that is needed to recover any NO 2 that was formed in the ventilator and in the gas lines from the reaction of NO and Oxygen. The recuperator can serve as a safety device to reduce the NO 2 levels to below 0.1 ppm, at any flow and at any NO concentration, prior to delivery to a patient.
In one embodiment, the flow resistance for the recuperator can be as low as possible, for example, less than 3 cm of water pressure at a flow of 60 L/minute, and/or <1 cm water at 15 L/min. The recuperator can operate at atmospheric pressure. The oxygen concentration at the recuperator can be in the range of 21% to 100%. The humidity at the recuperator can be 0% to 99%. The recuperator can be thermally insulated to prevent water condensation. The inlet to the recuperator can be from the humidified (and heated) line that is delivering gas to the patient. This line can be typically heated to about 35° C. to prevent water condensation in the lines.
The exit side of the recuperator can be a sample probe that goes to the NO/NO 2 gas analyzer. The sample line can be diluted with an equal volume of air so as to reduce the relative humidity and to minimize the rate of formation of NO 2 from Oxygen in the sample line 30 o to the analyzer. The weight of the recuperator can be kept as low as possible, so that it is not unwieldy, under 2 pounds but preferably under 1 pound or under 0.5 pounds. The exit from the recuperator can go directly to the patient by means of a short (approximately 6 inch) length of roughly 1 inch diameter ventilator tubing. The recuperator can be disposable and can be for a single use only. The recuperator can incorporate a particle filter to prevent any possibility that trace amounts of dust from the recuperator being delivered to a patient, for example, fine silica gel or ascorbic acid for the recuperator, or fine proline for the scavenger. The same filter material will also prevent bacteria and other particles from being delivered to the patient.
In one embodiment, the recuperator is provided as a disc as exemplified in FIGS. 2A and B. In a further embodiment, the recuperator can include a common filter design that is widely used in industry which is a tubular design with co-axial tubes. This type of design is especially common in water filters and for use in compressed in air lines. In another embodiment, the recuperator is provided as a tubular filter as exemplified in FIGS. 3A and B. As depicted in FIGS. 3A and B, the tubular filter can be constructed from three concentric tubes, with the filter medium being held tightly in place in a perforated section of the interior. The tubular filter can hold the silica gel or ascorbic acid dust in place in the annulus between the two perforated tubes. A filter medium can be placed on both contact sides of the silica gel or ascorbic acid dust. The powder or dust can be compressed during filing without the compression material coming into contact with the flowing air stream. The aspect ratio will be easier to handle adjacent to the patient, where a small diameter shape can be used. The tubular filter can include an exit shell as depicted in FIG. 3B , an inside shell that includes perforated inner and outer tubes with fixed annulus and an annulus filled with silica gel or ascorbic acid dust. The inner and outer annulus can be lined with filter material. In one embodiment, the final assembly of the tubular filter is depicted in FIG. 3B . The final assembly can include a top cap and an annular ring at the top can keep pressure on the silica gel or ascorbic acid dust.
In one embodiment, a method of NO and NO 2 gas sampling is provided. For example, for 100 ppm of NO and 100% oxygen, 1.70 ppm of NO 2 can be formed in the gas sampling lines from the reaction of NO with oxygen. The problem is how to sample for NO 2 in a gas stream that has the reaction of NO and oxygen going on at the same time. This is made worse at high NO concentrations. For example at 200 ppm NO the rate of formation of NO 2 in the sample line is 4 times the rate as compared to 100 ppm. Also at 100% oxygen the rate is 5 times the rate in air. To get an accurate reading of what was in the line at the patient there is a need to either sample quickly, or slow the reaction down somehow. By diluting by 50%, the rate is decreased 4 fold due to the drop in NO concentration and approximately 2.5 fold by the drop in Oxygen concentration.
In one embodiment, the sample tube from the patient to the detector can be diluted up to 66%, or up to 50% or up to 33%. The sample can be diluted at the sample point. The sample can be diluted with air. For example, dilution of one part sample and one part with air can reduce the water concentration in the sample. In another embodiment, the sample can also be diluted as follows: one part sample and two parts with air from the room (e.g. hospital room). Alternatively, the sample can also be diluted using bone dry air from the wall.
In a further embodiment, the sample tube can be spliced in two or three, adjacent to the sampling point on the recuperator. This can be done for 50 or 66% dilution.
EXAMPLES
Gas Cylinder Cartridge Design
In another aspect, the gas cylinder and appropriate amount of NO, for clinical use is provided. The FDA standard room size: 3.1×6.2×4.65 m=89.3 m=89,300 L. The OSHA NO 2 level is 5 ppm. All the three gas cylinders described herein are approximately equivalent in the amount of gas that they can deliver.
Size AS of the cylinder is pressurized to 2000 psi. The sudden release of the entire contents of 3600 L of 124 ppm would lead to a NO 2 level of 5.0 ppm in the room, if there was no air exchange. Thus, in order to meet the current FDA requirement for safety, the highest concentration in a gas cylinder of this size and type should be 100 ppm of NO 2 (with a built in safety factor). The cylinder that is used in the lab will deliver 3,600 liters of gas (without dilution) containing 100 ppm of NO 2 . At 5 L/min, this gas cylinder will last for 720 minutes=12 hours. At 48 pounds, without the regulator and top, this cylinder is far too heavy to be picked up by a nurse or therapist, and has to be moved on a wheeled cart.
Size AQ/BL/88 2000 psi cylinder is currently in use in hospitals. The sudden release of the entire contents of 1918 L of 233 ppm would lead to a NO 2 level in the hypothetical room of 5.0 ppm. Thus, in order to meet the current FDA requirement for safety, the highest concentration in a gas cylinder of this size and type should be 200 ppm of NO 2 (with a built in safety factor). For a cylinder of this size and 200 ppm of NO 2 , the ideal oxygen level would be 70-74%. This pressure cylinder will deliver 3836 liters of gas (after dilution) containing 100 ppm of NO 2 . At 5 L/min, this gas cylinder will last 767 minutes=12.8 hours. This cylinder weighs 30 pounds and is still too heavy to be picked up by a nurse. It is a bit more maneuverable but still needs a wheeled cart for transport.
Luxfer's ME36 3000 psi cylinder holds 992 Liters at a pressure of 3000 psi instead of 2000 psi. The sudden release of the entire contents of 992 L of 450 ppm would lead to a NO 2 level of 5.0 ppm in the hypothetical room. Thus, in order to meet the current FDA requirement for safety, the highest concentration in a gas cylinder of this size and type should be 400 ppm of NO 2 (with a built in safety factor). This cylinder however, weighs only 8.3 pounds compared to INO's 30 pounds. The contents of this small, high pressure cylinder would last as long as the AQ and the AS. This translates into the cylinders being used up at twice or four times the rate of INO but at less than ⅓ rd of the weight this is a reasonable trade off. The key advantage is that the cylinder is small and light enough to be stocked in a pharmacy and picked up by a nurse with one hand. The ideal oxygen level in a cylinder of this size would be about 60%. The Luxfer high pressure miniature gas cylinder will deliver 3968 liters of gas (with dilution) containing 100 ppm of NO 2 . At 511 min, this gas cylinder will last 793 minutes=13.2 hours. At only 8.3 pounds, this cylinder can be picked up by a nurse with one hand. It is small enough to be stored in a hospital pharmacy. The 3000 PSI is Luxfer Cylinder offers the best performance and is the preferred package. Table 1 shows the specifications of the cylinders described herein.
The physical layout of the recuperator is able to accommodate the 4.5 inch diameter cylinder, and an output tube that contains activated charcoal powder. As an example, a tube design is exemplified in FIG. 4 .
The revised design depicted in FIG. 5 has the two main tubes as close together as possible, with the small vertical tubes tucked in close. The entire package has to fit inside a 4.5 inch or less gas cylinder top. This is shown schematically in FIG. 5 . Each main tube that holds the ascorbic acid/silica gel dust has an inside diameter of about 1 inch. The inlet and outlet tubes need to be on the same side. The short tube can contain a small amount of activated charcoal to remove traces of acetaldehyde. Several embodiments of the entire package for use in an Intensive Care Unit are depicted in FIGS. 6A and B.
The gas bottle contains a mixture of 60% oxygen with the balance being N 2 . The gas also contains about 400 ppm of NO 2 . This gas leaves the gas cylinder through a built in regulator where the pressure is reduced to the 20 to 100 psi level. The gas is attached to a separate blending box by means of a unique quick disconnect.
The gas containing 400 ppm NO 2 is then blended with an air/oxygen mixture to reduce the NO 2 concentration to the therapeutic concentration. In current use, this is 0.1 to 80 ppm. In one aspect of the system, this could be extended upwards to >200 ppm. The blender dial is calibrated in ppm equivalents of NO. The gas leaving the blender flows onto the NO generation cartridge by means of a quick disconnect attachment. The air oxygen blender is a conventional design and is available commercially. The air and oxygen are typically supplied from the hospital wall supply as a utility. Alternatively, the gas can flow through the ventilator first before the cartridge to reduce the gas pressure from 50 to 20 psa.
The cartridge converts the NO 2 to NO. As the gas leaves the cartridge, the gas now has NO at the proper therapeutic concentration in an air oxygen blend of the appropriate oxygen concentration. The gas leaving the cartridge is connected back to the blending box by means of a quick disconnect fitting, where the oxygen concentration can be sampled and displayed. In one embodiment, an oxygen sensor can be used to precisely set the appropriate oxygen concentration.
The reason for the three connections to the blender box is to allow quick replacement of the gas cylinder. A second cylinder will be plumbed to an identical set of three quick disconnect fittings on the blender box. When a cylinder needs to be changed, a single three stack valve is used to switch from one gas cylinder to another, allowing for the empty cylinder to be replaced. This is not shown on the FIG. 6A .
The gas mixture from the blender box becomes replaces the oxygen feed on a conventional medical ventilator. The ventilator is then used in its conventional mode and can perform whatever ventilatory cycles that the therapist desires for a particular patient. The device is intended to provide the physician a mechanism for delivering a low concentration (dose) of pure NO gas in a mixture of oxygen and air. The gas passes through a mechanical or manual ventilator and travels through respiratory tubing and a mask or tube to the patient's lungs. The gas flow can be regulated by a mechanical ventilator or manual ventilation or by delivery directly to the patient from the pressurized gas tank (for spontaneously breathing patients). The device allows the physician to independently adjust the NO concentration and the oxygen concentration of the delivered gas.
Indication for Use
The device is indicated to provide pure NO gas at different concentrations in an oxygen/air mixture.
General Product Description
In one embodiment, The Nitric Oxide (NO) Generator and Delivery System include five components that work together to create, deliver and monitor pure Nitric Oxide (NO) gas in an oxygen/air mixture. The gas travels through standard anesthesia and respiratory breathing devices for inhalation by the patient. The anesthesia part is only needed to provide variable flow rates and/or to assist patients who are not breathing on their own. In its simplest form the gas bottle stands alone and the gas is converted to NO as it leaves the gas bottle. With this approach the gas is then fed into a mask or a cannula. The gas flow is provided by mechanical or manual ventilation or by the pressurization of the tank (for spontaneously breathing patients). The concentration of NO and Oxygen are determined and to adjusted by the physician based on each patient's condition and needs.
Product Components
Gas Tanks
The first component is a pressurized aluminum gas tank with a small quantity of Nitrogen Dioxide (NO 2 ) gas in an Oxygen/Air mixture. This mixture cannot be inhaled is without processing by the other components as it would be toxic. The tanks will come with a standard regulator to limit the pressure of the gas to the mixer. Tanks will have concentrated level of NO 2 gas and in a fixed Oxygen/Air ratio. These concentrations will be adjusted using the mixing system below. Tanks used or transport will be at set concentrations of NO 2 gas and Oxygen/Air and will not require mixing.
Mixing System
The mixing system includes two standard gas blenders that are connected and an oxygen sensor. The first mixing chamber takes medical oxygen and air, which can be provided from pressurized tanks or the hospital's gas system. A knob allows selection of the desired FiO 2 (fraction of inspired oxygen) of the gas to be delivered to the patient which adjusts the oxygen/air mixture in the mixing chamber as measured by the oxygen sensor. The output of this mixture is fed into a second mixing chamber where it is mixed with the NO 2 gas from the gas tank described above. The knob to this mixing chamber allows the physician to select the concentration of NO gas to be delivered to the patient. The output of this mixing chamber is the passed though the gas converter and purification cartridge described below. This allows variable NO and oxygen concentration levels which are independent of each other.
Gas Converter and Purification Cartridge
The gas mixture from the last mixer will flow through the Gas Converter and Purification cartridge. This cartridge will convert all NO 2 gas into NO gas and remove any impurities in the entire gas mixture. The concentration of NO gas will be the same as the concentration of the NO 2 gas as the conversion is essentially 100%. The concentration of the oxygen (oxygen/air ratio) will not be changed. The output of the cartridge will be delivered to the mechanical or manual ventilation system and appropriate pressures. Tanks used for transport will also be fitted with a flow meter to regulate the flow of the gas to the patient.
Recuperator Cartridge
The Recuperator cartridge will be placed at the patient end of the inspiratory limb of the patient's breathing tubing. This cartridge will contain the same technology as the Gas Converter The purpose of this cartridge is twofold. First, it will reconvert any NO 2 gas back into NO that may have formed through the reaction of the NO gas with oxygen. Second it provides bacterial and viral filtration of the delivered gas.
Disc Recuperator
The obvious format for the recuperator is to make it much like the gas cylinder device, but with the diameter of the order of 3 to 4 inches, and the cartridge depth reduced from 5.5 inches to less than 0.3 inches. A cartridge like this has a pancake shape and would look similar to the particle filters that are used with some respiratory equipment.
The equations below show how the pressure drop across the cartridge will vary as a to 20 function of radius and the depth. For a constant volume cartridge, the pressure drop varies with the fourth power of the radius.
V
1
=
π
r
1
2
l
1
l
1
=
V
1
/
π
r
1
2
p
∝
l
1
/
π
r
1
2
∝
V
1
π
r
1
2
×
π
r
1
2
∝
V
π
2
r
1
4
p
2
p
1
=
π
×
π
V
2
V
1
×
π
×
π
r
1
2
×
r
1
2
r
2
2
×
r
3
2
For constant volume of material
p
2
/
p
1
=
(
r
1
r
2
)
4
If volume material is half, then
p
2
/
p
1
=
0.5
(
r
1
r
2
)
4
The gas bottle cartridge, which has a radius of 0.4 inches and a depth of 5.5 inches, has a pressure drop that was measured experimentally of 2.7 psi=187 cm H 2 O water. The calculations of pressure drop for various diameters are shown in Table 2. A pressure drop of 0.2-0.3 cm water at 5 L/min is needed to attain the design goal of 3.0 cm H 2 O at 60 L/min. In order to achieve this low a pressure drop, the diameter of the flat disc would need to be 4.0 to 4.5 inches. If it were to have the same amount of material as the current cylinder cartridge, the depth would need to be 0.56 cm at 4.00 inches and 0.44 inches at 4.5 inches.
A flat disc of 3 inches diameter and a 1.0 cm thickness, has been tested in the laboratory and has been shown to perform as well as the cylinder cartridge. The variation of pressure drop with size, where all the filters have the same volume of material, is shown in FIG. 7 . Various concepts have been evaluated on how to build such a device. The difficulty is how to encapsulate the silica gel or ascorbic acid dust between two very thin filter cloths, and have not only uniform thickness everywhere, but also no settling of the silica gel or ascorbic acid dust. Settling would be catastrophic and could lead to channeling and failure. An example of one such design is shown in FIG. 2B .
A comparison of the pressure drop across the disc and tubular filters are shown mathematically below and in FIGS. 9A and B.
Dish Filter
Tube Filter
A = πr 2
A = 2πr · l
V = πr 2 t
V = 2πr · l · t
t
=
V
2
π
rl
For Cylinder:
p
∝
t
A
=
t
2
π
rl
=
V
(
2
π
rl
)
2
=
V
4
π
2
r
2
l
2
For Dish:
p
∝
V
π
2
r
2
r
2
Essentially, the analysis shows that the pressure drop of the tubular filter, like the disc filter, is proportional to the surface area (the inner circumference of the tubular filter) and the thickness of the bed. The detailed calculation of size and pressure drop are shown next and in FIGS. 9C and D.
Tube Calculation Continued
Volume of outer tube:
V 2 =πr 21 2 l
Volume of inner tube:
V
1
=
π
r
1
2
l
V
=
Volume
of
silica
gel
or
ascorbic
acid
Dust
=
V
2
-
V
1
=
π
r
2
2
l
-
π
r
1
2
l
r
2
=
Volume
π
l
+
π
r
1
2
l
π
l
=
Volume
π
l
+
r
1
2
For
Volume
=
2.76
cubic
inches
(
5.5
inches
-
0.8
inches
cylinder
)
r
1
=
0.5
inch
l
=
3.0
inches
r
2
=
2.76
π
×
3
+
(
0.5
)
2
=
0.29
+
0.25
=
0.54
=
0.73
gap
=
0.23
inches
≡
0.58
cm
Area
=
2
π
rl
=
2
π
(
0.5
)
(
3
)
=
94
sq
.
inches
Equivalent
area
to
disc
3.5
4
perimeter
Pressure
drop
=
0.5
cm
H
2
O
These equations were then used to evaluate a variety of shaped tubular filters and compared to the disc filter. For example, a 4 inch long tubular filter with an internal radius of 0.5 inch (1 inch id) and an outer annulus diameter of diameter of 1.25 inches would have an outer shell diameter of about 1.75 inches. A tubular filter with this aspect ration would have a pressure drop at 5 l/min of only 0.19 cm H 2 O, which is equivalent to a 4.5 inch diameter disc. The gap between the tubes, called the annulus, would have a spacing of 0.4 cm. See Table 3 From Table 3, assume that the performance of a disc that is 5 inches in diameter is wanted, which would have an effective surface area of 19.63 sq inches and a pressure drop of 0.12 cm of water. In a tubular version, the same surface area and pressure drop can be achieved with a inside diameter of 0.57 inches and an od of 0.70 inches, provided that the tube was 5.50 inches in length.
Gas Monitoring
The system may require gas sensors to monitor and display the concentration of NO and NO 2 that is delivered to the patient. These can be commercially available monitors and should be equipped with alarm capability. A figurative representation of the system is shown on FIG. 8 .
For 100 ppm of NO and 100% oxygen, it is shown by both experiment and calculation that 1.70 ppm of NO 2 is formed by the time the sample passes through about 2 meters of tubing, thru a large volume water drop out filter and into the PrinterNox, which is a commercial electrochemical gas analyzer for measuring NO and NO 2 for inhalation applications. The sample can also be >100 saturated with water and the water drop out filter is essential. This is a typical problem that is encountered in stack monitoring from incinerator and power plant smoke stacks. There are several possible solutions:
First, heat the sample lines to keep the water in the vapor phase. If the instrument also runs hot, then the water filter can be eliminated and the sampling time reduced, thereby reducing the NO 2 formation. It is not a good approach for NO 2 sampling since the rate of formation is linear with time and square power with NO 2 .
Second, sample at the source. This does work, but the condensing water issue remains.
Third, dilute the sample. This does three critical things:
1. It dilutes the sample which reduces the formation of NO 2 from NO and O 2 . This makes sampling down lines possible otherwise most of the NO that is measured at the analyzer will be formed in the sampling lines. 2. It decreases the humidity, which prevents condensation of water in the lines and to thereby eliminates the need for a water drop out filter. 3. It reduces the NO level by 50% which brings the machine into the working range of the PrinterNOx detection cells
Consider a Sample Tube with Dilution of One (50%).
Initial conditions: 100 ppm NO, 100% oxygen and condensing water (>100%) With 50% dilution: 50 ppm NO, 60.5% oxygen, and greatly reduced humidity. At detector: Rate of formation of NO 2 reduced by 4*100/60.5=6.6 NO 2 reduced from 1.70 to 0.26 ppm
With removal of the large volume water condensation filter volume, the level will come down even further.
NO readings are reduced at all concentrations by 50%. This means 20 ppm reads as 10, and 2 ppm reads as 1 ppm. This is corrected for by calibration, but the precision will be reduced by 50%.
NO 2 formation in the lines is effectively reduced to zero at normal concentrations. For example, even at 80 ppm NO, the NO 2 formed in the lines would be 1.09 ppm without dilution and <0.16 ppm with dilution.
Consider a Sample Tube with Dilution of Two (33%).
Initial conditions: 100 ppm NO, 100% oxygen and condensing water (>100%) With 33% dilution: 33 ppm NO, 47% oxygen, and greatly reduced humidity. At detector: Rate of formation of NO 2 reduced by 9*100/47=20 NO 2 reduced from 1.70 to 0.09 ppm
NO readings are reduced at all concentrations by ⅓rd. This means 20 ppm reads as 6.67, and 2 ppm reads as 0.67 ppm. This is corrected for by calibration, but the precision will be reduced by ⅓ rd .
NO 2 formation in the lines is effectively reduced to zero at normal concentrations. For example, even at 80 ppm NO, the NO 2 formed in the lines would be 1.09 ppm without dilution and <0.05 ppm with dilution.
Humidity
At 37° C., body temperature, the amount of water at 100% relative humidity is 44 to g/M 3 . The air in a hospital is typically at 50% relative humidity and a temperature of 22° C. Air at this temperature contains 10 g/M 3 .
Diluting one part sample and one part with air from the hospital room would reduce the water concentration in the tube down to 27 g/M 3 . This amount of water vapor would begin to condense out of the air at a temperature of 28° C. (82° F.).
Diluting one part sample and two parts with air from the hospital room would reduce the water concentration in the tube down to 21.3 g/M 3 . This amount of water vapor would begin to condense out of the air at a temperature of 23.5° C. (74° F.).
An alternative approach would be to use bone dry air from the wall. This will be available in the same box and could be piped to the sample location by means of a parallel tube.
The detectors are required to run at constant temperature so as to ensure stability. Thus the inside of the detection module would be warm. A 50:50 dilution would work as long as the sample lines were insulated by a thick wall or by having one tube run inside another.
Application (for 50% or 66% Dilution)
The sample tube could be spliced in two (or three), adjacent to the sampling point on the recuperator. Alternatively, the second sampling orifice could be molded into a special adaptor. It would be best not to have a flapping air sample port, since it would raise too many questions from users. This would allow for taking half the sample from the patient inspiratory line and half the sample from the room. Calibration would also have to be at this point. Technically, this would be a perfectly valid way to operate and would meet all regulatory approval guidelines. Naturally, the approach be described in regulatory submissions which would also reference the EPA standard procedures.
Dilution at the sample point is a perfectly viable approach. There would also probably be no need to have the large dead volume water condensation trap on the detector. This would reduce the NO 2 formation level even further, by as much as a factor of 5. The life of detector cells would increase from days to about 12 months, even during in house testing. Dilution is the preferred method of sampling the reactive gas stream.
Other Applications
The gas bottle alone can be used for all applications of NO. It is available to deliver the gas without any electronics whatsoever. The advantages of the system are simplicity, no mixing, no electronics and no software. Just connect the regulator and open the valve.
The gas bottle system can also be used with a dilutor. In this case the gas would be shipped as say 1000 ppm of NO 2 in oxygen. In a first stage, the user's equipment would then dilute this concentration down to say 20 ppm NO 2 . The second stage would be to insert the cartridge and convert to NO. this format would be similar to what is currently marketed, but would not require the user to worry about any NO 2 that was formed in the gas lines since it would be removed by the recuperator. Similarly, the recuperator cartridge could be used with existing system to convert all of the residual NO 2 gas being inhaled into the therapeutic form, namely NO. The recuperator also ensures that no NO gas is lost from the system and that the patient is receiving the full prescribed dose.
The fact that the system can deliver high doses of NO, of the order of 100 to 200 ppm or even higher, without the presence of the toxic form, NO 2 , may be important. Much of the earlier work was done at doses in the 20 ppm range, but the researchers were always plagued by the presence of toxic NO 2 . This limited the does that they could go to. With the system all of the NO 2 toxicity problems in the inhaled gas are eliminated. This fact alone will greatly increase the utility of NO gas for treatment of a multitude of diseases, and especially ARDS (Acute respiratory distress syndrome).
Other implementations are within the scope of the following claims.
TABLE 1
Max
Height
Diameter
Internal
Weight
Conc
Name
Inches
Inches
Volume L
Pounds
Pressure
Volume L
PPM
LAB
AS
48
8
29.45
48
2000
3600
100(124)
INCURRENT
AQ/BL/88
33
7.25
15.57
30
2000
1918
200(233)
USE
LUXFER
ME36
25.3
4.4
4.5
8.3
3000
992
400(450)
TABLE 2
DISC RECUPERATOR
PRESS
DIAM D
RADIUS r
DROP
mm
THICKNESS
INCHES
INCHES
r 2
AREA
r 4
cm H 2 O
H2O
INCHES
CM
Base case
0.80
0.40
0.160
0.503
0.0256
187.00
1870.00
5.5
13.97
1.00
0.50
0.250
0.785
0.0625
76.60
765.95
3.52
8.94
1.50
0.75
0.563
1.767
0.3164
15.13
151.30
1.56
3.97
2.00
1.00
1.000
3.141
1.0000
4.79
47.87
0.88
2.24
2.50
1.25
1.563
4.908
2.4414
1.96
19.61
0.56
1.43
3.00
1.50
2.250
7.068
5.0625
0.95
9.46
0.39
0.99
3.50
1.75
3.063
9.621
9.3789
0.51
5.10
0.29
0.73
4.00
2.00
4.000
12.566
16.0000
0.30
2.99
0.22
0.56
4.50
2.25
5.063
15.903
25.6289
0.19
1.87
0.17
0.44
5.00
2.50
6.250
19.634
39.0625
0.12
1.23
0.14
0.36
const
volume
TABLE 3
DISC
CYL
CYL
CYL
DISC
DISC
PRESS
CYL
INSIDE
OUTSIDE
CYL
CYL
PRESS
diam
AREA
DROP
AREA
rad
rad
LENGTH
GAP
DROP
INCH
sq inch
cm-H20
sq in
inch
inch
inch
cm
cm H2O
2.00
3.14
4.79
2.50
4.91
1.96
3.00
7.07
0.95
7.23
0.50
0.79
2.30
0.75
0.95
3.50
9.62
0.51
9.42
0.50
0.74
3.00
0.60
0.51
4.00
12.57
0.30
12.57
0.50
0.69
4.00
0.47
0.30
4.50
15.90
0.19
15.58
0.62
0.78
4.00
0.40
0.19
5.00
19.83
0.12
19.70
0.57
0.70
5.50
0.32
0.12 | Various systems, devices, NO 2 absorbents, NO 2 scavengers and NO 2 recuperator for generating nitric oxide are disclosed herein. According to one embodiment, an apparatus for converting nitrogen dioxide to nitric oxide can include a receptacle including an inlet, an outlet, a surface-active material coated with an aqueous solution of ascorbic acid and an absorbent wherein the inlet is configured to receive a gas flow and fluidly communicate the gas flow to the outlet through the surface-active material and the absorbent such that nitrogen dioxide in the gas flow is converted to nitric oxide. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to fluid pumps, and in particular to gear pumps and other positive displacement hydraulic pumps, which can be used to deliver hydraulic fluid to two different sets of hydraulic loads. A priority valve is needed to distinguish between the two loads, and deliver hydraulic fluid preferentially to a first load up to a first working pressure, and only then deliver hydraulic fluid to the second load which is a non-preferential load.
2. Description of the Related Art
Priority valves are known which divide the flow from a hydraulic pump into preferred and non-preferred flows for servicing two loads as indicated above. The majority of such priority valves have been connected in series with the pump output, being connected to the pump by conduits and to the first and second loads by further conduits.
In GB 2298902, the present Applicant discloses a pump incorporating an integral priority pressure regulating valve. The valve is spring biased at one end face in a direction to permit fluid communication between a high pressure chamber of the pump and a main port connected to the preferential load only. An opposing end face of the valve is supplied with hydraulic fluid from the main port in such a manner to counter the spring bias. When the main port receives hydraulic fluid of a predetermined pressure, the pressure on the opposing end face is sufficient to overcome both the compressive force developed by the spring and the static friction associated with the valve, thereby enabling the movement of the valve to a position where it permits fluid communication between the high pressure chamber and an auxiliary port which is connected to the non-preferential load. This pump is much simpler to install than one requiring a separate priority pressure regulating valve to be inserted in the pipeline or conduit between the pump and the main and auxiliary loads, and there is a much lesser tendency for fluid leakage.
In this arrangement, the spring provided to bias the valve must be of sufficient strength so as to meet the total reaction developed against it when fluid of the predetermined pressure is applied to the non-spring end face of the valve. Quite often, the predetermined pressure selected is relatively high and hence the loading on the spring can be excessive.
The characteristics of the spring are extremely important since the spring must be compressed to a depth equal to the length through which the valve is require to travel without exhibiting substantial changes in its reaction against the valve, otherwise the reaction developed by the spring against the valve will increase significantly as the spring is compressed.
Furthermore, whereas pressure is uniformly applied to the non-spring end face of the valve from the main port, the force exerted by the spring on the valve is localized through the points of contact between the spring and the valve. This may induce distortion of the valve profile.
Additionally, as the spring is an integral component to the pump, it is a relatively difficult operation to adjust or replace the spring so as to provide the pump with a new predetermined pressure setting.
Therefore, it is an objective of the present invention to significantly reduce the problems identified above in relation to the prior art. This is achieved by means of pilot operation.
BRIEF SUMMARY OF THE INVENTION
The invention provides a fluid pump having a housing, a main output port, an auxiliary output port and a priority pressure regulating valve contained within the pump housing. The priority pressure regulating valve includes a spool having two opposing end faces. Each of these end faces is disposed within a chamber which is in fluid communication with the main output port. A force means is also included in association with one of the spool end faces to bias the spool to a position where it causes fluid developed by the pump to flow to the main output port exclusively. A pressure release means is provided in fluid communication with one of the chambers to enable fluid to flow from said one of the chambers when the pressure at the main output port is at a predetermined working pressure thereby establishing a pressure differential across the two end faces of the spool which is sufficient to overcome the bias developed by the force means thus causing the spool to move to a position where it permits fluid developed by the pump to flow to the auxiliary output port.
In a preferred embodiment, that chamber which is in fluid communication with the pressure release means houses the force means. In this arrangement, the force means is preferably a coil spring in compression.
Alternatively, the force means may be provided in the chamber which is remote from that which is in fluid communication with the pressure release means. In these circumstances, the force means may be a coil spring in tension.
Preferably, the pressure release means includes a poppet, a regulating spring and an adjuster, wherein one face of the poppet is in fluid communication with one of the chambers and the regulating spring is disposed to resist the force exerted on the face of the poppet by the pressurized fluid contained in said chamber. The poppet may be located between said chamber and a channel such that when the pressure exerted on the poppet by the fluid in said chamber overcomes the opposing force exerted on the poppet by the regulating spring, fluid communication is established between said chamber and the channel.
In a preferred embodiment of the invention, the channel drains to an inlet of the pump.
The regulating spring may be a helical spring in compression which engages that face of the poppet which opposes the face which is in fluid communication with said chamber. Additionally, that end of the regulating spring which is remote from the poppet may abut the adjuster in a manner such that the adjuster can be moved along the axis of the regulating spring to adjust the compressive force exerted on the poppet by the regulating spring.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a transverse section through a gear pump according to the invention, taken along the axis of the priority pressure regulating valve of the pump, showing a spool of the valve in a position in which it delivers hydraulic output fluid to a main or priority outlet port at a pressure below a predetermined level;
FIG. 2 shows the pump of FIG. 1 in a condition wherein the pressure of the hydraulic fluid developed by the pump just equals the predetermined pressure required at the main or priority outlet port; and
FIG. 3 shows the pump of FIG. 1 in a condition wherein the pressure of the hydraulic fluid at the main or priority outlet port has just been reduced to a level slightly less than the predetermined pressure.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 illustrates a gear pump 2 according to a preferred embodiment of the invention. The pump 2 has a housing 4 within which is disposed the pumping elements 6 of the pump 2 , an accurately machined bore 17 , a priority outlet port 10 and an auxiliary outlet port 14 . The housing 4 and pumping elements 6 can be of types as used in relation to any conventional positive displacement hydraulic fluid pumps.
As shown in FIG. 1, the bore 17 extends throughout the entire transverse length of the pump 2 and is hydraulically sealed at either end. On the left, the seal is achieved by a washer 19 which is mounted over a threaded bolt 18 in a conventional manner. The threaded portion of the bolt 18 engages with threads provided on the circumferential wall of the bore 17 . On the right, the seal is achieved by an O-ring seal 32 disposed on a screw end cap 30 which also is removably engaged with the housing 4 .
High pressure fluid developed by the pumping elements 6 is delivered through a supply channel 8 in the housing 4 to a supply annulus 9 machined into the wall of the bore 17 . A spool 20 is provided within the bore 17 and is capable of axial movement along the length of the bore 17 . Depending on its position, the spool 20 is capable of permitting high pressure fluid to flow from the supply annulus 9 to one or both of a first 12 and a second 16 output annulus provided on the wall of the bore 17 . The first output annulus 12 communicates directly with the priority outlet port 10 , while the second output annulus 16 communicates directly with the auxiliary outlet port 14 .
A first orifice and blind axial drilling 2 . 2 and a second orifice and blind axial drilling 24 are provided in the spool 20 . These are constantly in fluid communication with the priority outlet port 10 . The first blind drilling 22 delivers fluid to the right hand end face of the spool 20 . The second blind drilling 24 delivers fluid to the left hand end face of the spool 20 where it communicates with a second pressure chamber C 2 defined by the wall of the bore 17 , the threaded bolt 18 and the left hand end face of the spool 20 .
The screw end cap 30 has a first pressure chamber C 1 which contains a frictional spring 34 . This is a compressed helical spring which, during operation, is used to bias the spool 20 to the left as shown in FIG. 1 . The frictional spring 34 is mounted on a cylindrical spring carrier 36 (shown in FIG. 2 ). The spring carrier 36 extends from the screw end cap 30 into the bore 17 so as to abut the right hand end face of the spool 20 . The spring carrier 36 has an axial channel to permit fluid communication between the first orifice and blind drilling 22 and the first pressure chamber C 1 . As such, the spool 20 , through the spring carrier 36 , is biased by the frictional spring 34 to the left end of the bore 17 .
In addition to the first pressure chamber C 1 , the screw end cap 30 also houses a pilot 40 . The pilot 40 consists of a poppet 42 , a regulating spring 44 , a threaded adjuster 46 and two lock nuts 48 . The regulating spring 44 is in compression and biases the poppet 42 to the left.
Depending upon the pressure of the hydraulic fluid in the first pressure chamber C 1 and the biasing force exerted by the regulating spring 44 , the poppet 42 can prevent or permit fluid to flow from the first pressure chamber C 1 through a drain channel 50 to a tank or, preferably, to an inlet of the pumping elements 6 . Once the pressure of the fluid in the first pressure chamber C 1 is sufficient to overcome the opposing compressive force developed by the regulating spring 44 , the poppet 42 lifts against the spring 44 and thereby allows fluid to flow from the first pressure chamber C 1 to the drain channel 50 . The screw end cap 30 is provided with a removable plate 38 which enables the user to access the lock nuts 48 and the threaded adjuster 36 . By rotating the threaded adjuster 36 , the user changes the compressive force exerted by the regulating spring 44 on the poppet 46 , and hence changes the predetermined pressure setting at with the poppet 42 lifts.
In comparison to the pump disclosed in GB 2298902, the regulating spring 44 of the present invention can be made substantially stiffer since it is only compressed slightly and is not required to be compressed to the extent to which the spool moves along the bore as in the prior art. Indeed, the regulating spring 44 is only required to generate relatively low loads compared with the single spring design of the prior art. Additionally, in the prior art pump, when the predetermined pressure is established, the spool commences to compress the regulating spring but as the spring is compressed the reaction that it exerts on the spool progressively increases and therefore the pressure required to counteract the spring's reaction is required to increase. Hence, as the spool traverses along the bore the predetermined pressure changes. In the present invention, use of the regulating spring 44 in the pilot 40 gives a more definite predetermined pressure throughout operation as it is used to counteract the pressure only and not the movement of the spool 20 .
In the present embodiment, on start-up, and at all other instances when the pressure of the fluid developed by the pumping elements 6 is less than the predetermined pressure, the spool 20 is biased to the position as shown in FIG. 1 by the frictional spring 34 . Thus, fluid in the supply annulus 9 is delivered initially past a first land 26 (see FIG.2) to the first output annulus 12 which communicates with the priority outlet port 10 . At this stage a second land 28 (FIG.2) provided on the spool 20 blocks hydraulic flow to the auxiliary output port 14 . The pressure of the fluid at the priority outlet port 10 is communicated to the first and second pressure chambers C 1 ,C 2 by the respective orifices and blind drillings 22 , 24 . Since the pressure of the fluid is not sufficient to lift the poppet 42 of the pilot 40 against the regulating spring 44 , the spool 20 is pressure balanced across its end faces and the frictional spring 34 exerts a slight force on the spool 20 through the spring carrier 36 ensuring that the spool 20 remains in the same position to the left of the bore 17 .
In FIG. 2, the pressure of the fluid developed by the pumping elements 6 has just reached the predetermined level. Under these conditions, the pressure of the fluid at the priority outlet port 10 , in the first pressure chamber C 1 and in the second pressure chamber C 2 is at the predetermined pressure. Therefore, the pressure of the fluid in the first pressure chamber C 1 is sufficient to lift the poppet 42 against the regulating spring 44 and fluid is allowed to flow from the first pressure chamber C 1 through the drain channel 50 to the inlet of the pumping elements 6 . This produces a pressure drop in the first pressure chamber, and thereby a pressure differential is established across the two end faces of the spool 20 . The differential is more than sufficient to overcome the slight reaction exerted by the frictional spring 34 and hence the spool 20 moves to the right enabling fluid in the supply annulus 9 to be communicated to the auxiliary outlet port 14 as well as the priority outlet port 10 .
If the pressure of the fluid developed by the pumping elements 6 continues to be maintained at or above the predetermined level, the spool 20 continues to move until it reaches the extreme right hand position as shown in FIG. 3 in which a shoulder portion of the spool 20 abuts a stop washer that is retained in position by the screw end cap 30 . In this position, fluid communication between the supply annulus 9 and the priority outlet port 10 is interrupted by the first land 26 provided on the spool 20 , and fluid communication is exclusively established between the supply annulus 9 and the auxiliary outlet port 14 . If at this instance, the pressure at the priority outlet port 10 is greater than the predetermined level, the excess fluid is permitted to flow from the priority outlet port 10 through the first orifice and blind axial drilling 22 , through the channel provided in the spring carrier 36 and through the first pressure chamber C 1 to the drain channel 50 . Thereby the pressure at the priority outlet port 10 is reduced until the predetermined level is achieved, at which point the poppet 42 blocks fluid from flowing from the first pressure chamber C 1 to the drain channel 50 (as shown in FIG. 3 ). This establishes a pressure balance across the respective end faces of the spool 20 and the frictional spring 34 moves the spool 20 back to the left. If the pressure of the fluid developed by the pumping elements 6 is still greater than the predetermined level, the spool 20 moves back to the right, otherwise it moves to the position shown in FIGS. 1 and 2.
Thus the spool 20 preferentially feeds the priority outlet port 10 with a regulated pressure supply. When the supply is satisfied so that the pressure in the priority outlet port 10 reaches a predetermined working pressure, the spool 20 moves so that hydraulic fluid delivered by the pump 2 continues to be delivered, but to the auxiliary outlet port 14 rather than exclusively to the priority outlet port 10 .
The pressure at the auxiliary outlet port 14 can be greater than or less that the pressure at the priority outlet port 10 . If the predetermined working pressure, which is the pressure required at the priority outlet port 10 , is less than the working pressure at the auxiliary outlet port 14 the latter pressure can be allowed to rise until it reaches a maximum rated output pressure of the pump 2 . Alternatively, the working pressure at the auxiliary outlet port 14 can be limited by a pressure relief valve (not shown in the drawings) with excess hydraulic fluid being returned to drain. | A fluid pump has a housing ( 4 ), a main output port ( 10 ), an auxiliary output port ( 14 ) and a priority pressure regulating valve contained with the housing ( 4 ). The priority pressure regulating valve has a spool ( 20 ) to direct fluid to one or both of the of the output ports ( 10,14 ), a force means ( 34,36 ) associated with the spool to bias the spool ( 20 ) to a position where it causes fluid to flow to the main output port ( 10 ) exclusively, and a pressure release means ( 40 ) which enables the spool ( 20 ) to move to a position where it permits fluid to flow to the auxiliary output port ( 14 ) when the pressure at the main output port ( 10 ) is at or greater than a predetermined pressure. | 5 |
FIELD OF THE INVENTION
[0001] This invention relates to the field of systems for securing and transporting equipment in the cargo bed of a transport vehicle.
BACKGROUND OF THE INVENTION
[0002] Personal recreational vehicles, such as motorcycles, snowmobiles and all terrain vehicles have become increasingly popular in recent years. These vehicles are typically transported to a remote site for use via a transport vehicle, such as pick-ups, trucks, trailers, and other types of vehicles. Normally, these transport vehicles are not particularly designed for securely transporting the recreational vehicles. The recreational vehicles must be secured in place on the transport vehicle. The available systems for securing the recreational vehicle range from simple ropes and straps to complex support systems that are permanently mounted on the bed of the transport vehicle.
[0003] The use of ropes and straps require extensive rigging to ensure that the recreational vehicle is secure in the transport vehicle. It is difficult to find adequate securing points on both the recreational vehicle and the transport vehicle. Also, these ropes and straps may loosen and cause the recreational vehicle to become insecure in the transport vehicle.
[0004] There are accessory systems for securing the recreational vehicle in the cargo bed of the transport vehicle. Unfortunately, these systems are usually permanently mounted to the transport vehicle which may interfere with other uses of the transport vehicle. Also, these systems are usually dedicated to a particular recreational vehicle and not useable with other recreational vehicles.
[0005] The prior systems fail to provide a positive engagement mechanism that safely secures the recreational vehicle in the transport vehicle. The prior systems are not able to be quickly and easily removed from the transport vehicle without causing damage to the transport vehicle. The prior systems do not allow the recreational vehicle to be locked safely in the transport vehicle. Also the prior systems do not allow quick changes to the system for other types of vehicles to be secured in the system.
[0006] The prior systems typically operate by forcing the shock absorber systems to compress downward to hold the vehicle in place. This creates pressure within the shock absorber systems that causes seals to degrade and leak.
[0007] Thus a need exists for a system for securing recreational and other types of vehicles in a transport vehicle without the problems of the prior art systems.
SUMMARY OF THE INVENTION
[0008] The present invention solves these and other problems by providing systems for securing recreational vehicles to a transport vehicle quickly with a positive engagement mechanism. The systems are also designed to be quickly installed in the transport vehicle without causing any permanent damage to the transport vehicle. The systems may also be quickly changed out to allow other types of recreational vehicles to be transported as well.
[0009] The present invention in a preferred embodiment includes a positive engagement mechanism that locks the recreational vehicle to the transport vehicle. In one embodiment, the system includes a clip member having engagement teeth that engage a latch mechanism mounted in the transport vehicle. This clip member may be mounted directly onto the recreational vehicle or else mounted onto a locking bar that secures over a portion of the recreational vehicle.
[0010] In one preferred embodiment, the system includes a yoke or diamond shaped bracket into which the front wheel of a motorcycle may be engaged and supported. Clip members that are mounted on the motorcycle forks engage in latch mechanisms mounted on this yoke or bracket. The latch mechanisms are resilient to allow the clips members to slide into the latches, then lock in place to prevent the clips from accidentally disengage. A release mechanism, such as a release bar, is activated to allow the clips to disengage at the appropriate time.
[0011] In another preferred embodiment, the system includes the clip members mounted onto the motorcycle wheel for engagement into latch mechanisms on the yoke or bracket or other engagement mechanism.
[0012] Another preferred embodiment of the present invention mounts the clip members onto the frame of the motorcycle for engagement with a latch mechanism mounted onto the transport vehicle.
[0013] The present invention in a preferred embodiment provides a positive engagement locking system for motorcycles and other vehicles. This allows the motorcycle to be securely locked without damaging the shock absorbers.
[0014] An additional preferred embodiment of the present invention mounts the clip members as described above onto the foot peg assembly of the motorcycle. The clip members engage in the latch assembly mounted on the transport vehicle.
[0015] In another preferred embodiment, the system includes a platform that has a locking bar mounted to it. The end of the locking bar includes a clip member having angled teeth. A latch mechanism is mounted on the platform to engage the clip member to lock the locking bar in place. The locking bar is secured over a portion of the recreational vehicle and locked into place by the clip and latch mechanism.
[0016] Another embodiment of the present invention provides an adjustable mechanism for mounting the securing system in the transport vehicle. This adjustable mechanism includes engagement mechanism that engage against the inner sidewalls of the transport vehicle. Alternatively, the system can be bolted to the transport vehicle if there are no sidewalls available.
[0017] The system in a preferred embodiment also provides a plurality of spaced mounting holes that allow multiple systems mounted on the transport vehicle. Also, different systems for different vehicles may also be mounted as well.
[0018] These and other features of the present invention are evident from the ensuring detailed descriptions of preferred embodiments and from the drawings.
BRIEF DESCRIPTIONS OF THE DRAWINGS
[0019] FIG. 1 is a perspective view of the base platform of a preferred embodiment of the present invention.
[0020] FIG. 2 is a perspective view of the engagement mechanism of the base platform of FIG. 1 .
[0021] FIG. 3 is a perspective view of the assembled mounting system of the embodiment of FIG. 1 .
[0022] FIG. 4 is a side view of the mounting system of FIG. 3 mounted in a transport vehicle.
[0023] FIG. 5 is a perspective view of the securing system of a preferred embodiment of the present invention.
[0024] FIG. 6 is a perspective view of the foot release bar of a preferred embodiment of the present invention.
[0025] FIG. 7 is a front view of the securing system of FIG. 5 .
[0026] FIG. 8 is a side view of the securing system of FIG. 5 .
[0027] FIG. 9 is a perspective view of the securing system of FIG. 5 with the latch mechanism exposed.
[0028] FIG. 10 is a front view of the exposed latch mechanism.
[0029] FIG. 11 is a perspective view of the clip member of a preferred embodiment of the present invention.
[0030] FIG. 12 is a perspective view of the clip member of another preferred embodiment.
[0031] FIG. 13 is a side view of the clip member mounted to a motorcycle.
[0032] FIG. 14 is a side view of the motorcycle engaged in the securing system.
[0033] FIG. 15 is a side view of another preferred embodiment of the present invention.
[0034] FIG. 16 is a perspective view of the embodiment of FIG. 15 .
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0035] The present invention provides systems for securely transporting recreational vehicles in the cargo bed of a transport vehicle. Preferred embodiments of the present invention is discussed below with particular relevance to motorcycles, snowmobiles and all terrain vehicles. It is to be expressly understood that this descriptive embodiment is provided for explanatory purposes only and is not meant to limit the scope of the claimed invention. Other types and uses of such systems are also considered to be within the scope of the present invention. For example, the system of the present invention may be used for wheelchairs, mobility systems, bicycles, for golf carts, small tractors, personal watercraft and other types of vehicles.
[0036] A preferred embodiment of the present invention is illustrated in FIGS. 1-16 . This system 10 includes base platform 20 shown in FIG. 1 . Base platform 20 includes parallel members 22 , 24 that extend just less than the width of most pick-up beds. It is also to be understood that in another embodiment the members 22 , 24 are adjustable in their length to accommodate most cargo beds of other transport vehicles. Cross members 28 , 30 secure the members 22 , 24 to one another. Pads 26 are intermittently mounted to the lower surface of the members 22 , 24 to minimize scratching of the cargo bed during use. These pads may be rubber, or any other suitable material.
[0037] Spaced holes 32 are formed along each of the members 22 , 24 for securing the frames 60 as will be discussed in greater detail below. Brackets 34 , 36 , 38 , 40 are mounted upright to the ends of members 22 , 24 . These brackets include upright plates 42 with holes 44 formed in those plates.
[0038] Engagement mechanisms 50 shown in FIGS. 2-4 are mounted to the base platform 20 to secure the base platform in the cargo bed of a pickup without the need to drill or permanently mount the base platform to the cargo bed or to permanently alter the pickup bed. The engagement mechanisms 50 include base member 52 having internal thread portions 54 on each end. Support members 56 , 58 extend upwardly from the base member. Upper portion 60 is attached to these support members. It is to be expressly understood that the shape and configuration of the support members, base member and upper portion can be of any shape or configuration.
[0039] The engagement mechanisms 50 are pivotally mounted to the base platform 20 . Bolts engage the internal thread portions 54 on the base member 52 through the holes 44 in the plates 42 on the brackets 40 on the base platforms. This allows the engagement mechanisms 50 to pivot relative to the base platform 20 as shown in FIGS. 3-4 .
[0040] Threaded rod 64 extends downward into hole 66 formed in the upper portion 60 . Nuts 68 are mounted onto the threaded rod 64 above the upper portion. Engagement member 70 is mounted on the upper end of the threaded rod 64 .
[0041] In use the height of the engagement member 70 can be adjusted by rotation of the nuts 68 in opposing directions. This allows the height of the engagement member 70 relative to the base platform as shown in FIG. 4 to engage the rail surface of the pickup bed to install the base platform 20 in the cargo bed. The nuts can be rotated in the opposing directions to lower the engagement members to remove the base platform from the cargo bed.
[0042] It is to be expressly understood that the engagement mechanisms 50 can be eliminated if the base platform is to be permanently installed or installed in the cargo bed of a trailer, flatbed truck or other transport vehicle that may not have a sidewall. Also, other engagement mechanisms may be used as well.
[0043] The base platform 20 as discussed above is intended for use with one or more vehicle securing systems. The base platform 20 may be installed in most if not all pick-up cargo beds, flatbeds, trailers, vans, trucks, containers and any other type of transport vehicle.
[0044] One such securing system is illustrated in FIGS. 5-14 . This securing system 80 is intended for motorcycles or other wheeled vehicles. The system 80 includes diamond shaped yoke 82 . The sides 84 , 86 , 88 , 90 of the yoke are supported by base members 92 , 94 . The base members 92 , 94 includes mechanisms such as bolts extending through holes formed in the base members that will engage the holes 32 of the base platform 20 . The yoke may be secured in the center portion of the base platform or multiple yokes may be mounted on the base platform.
[0045] The dimensions of the yoke are selected so that the front wheel of the vehicle will fit inside the inner portion of the yoke with points of contact at the top of the yoke and the base members 92 , 94 .
[0046] Brackets 100 , 101 are secured to the center opposing inner portions of the yoke 82 . These brackets in this preferred embodiment are formed of plastic, elastomeric, rubber or other durable materials. The brackets 100 , 101 are shaped to allow the front wheel of the vehicle to easily but securely roll in between and held there. Protrusions 102 , 104 are formed on the front surface of the brackets to dampen the movement of the vehicle as it is engaged in the yoke.
[0047] Slots 106 , 108 are formed in the brackets 100 , 101 . Latches 110 , 112 are mounted within these slots 106 , 108 . These latches include teeth 114 that engage clips 130 that are discussed in greater detail below. These latches include hole 116 formed as part of the latch release system. The latch release system includes a foot release pedal 120 that is mounted to the upper yoke arms 84 , 86 by axle pins 118 , 119 . This allows the foot release pedal 120 to pivot relative to the yoke. The foot release pedal extends downward beyond the sides of the yoke.
[0048] Offset pin members 122 , 124 are mounted to the foot release pedal and extend inward through the brackets 100 . The offset portions 126 , 128 are mounted into the holes 116 of the latches 110 , 112 . Thus, when the lower portion of the foot release pedal 120 is pressed inward, the pedal pivots away from the yoke. This causes the offset pin members 122 , 124 to move the teeth 114 of the latches 110 , 112 away from the clips 130 as discussed in greater detail below.
[0049] Clips 130 shown in FIG. 11 include flexible members 132 having angular teeth 134 . Mounting brackets 136 are formed on the upper end of the clips with mounting holes 138 , 140 . The mounting holes may be formed in the same plane as the teeth 134 as shown in FIG. 11 or perpendicular to the teeth as shown in FIG. 12 with mounting holes 142 , 144 formed in mounting bracket 146 perpendicular with teeth 148 . The clips may be metal, plastic or preferably flexible plastic teeth reinforced with metal.
[0050] The clips 130 or 150 are mounted to the front forks of the motorcycle as shown in FIG. 13 or other wheeled vehicle. In use, the motorcycle is loaded into the cargo bed of the transport vehicle. The front wheel of the motorcycle or other vehicle is simply rolled into the yoke 82 until the wheel engages the points of contact at the top and bottom of the yoke. The clips 130 engage into the latches 110 , 112 on the brackets of the yoke. The latches are resilient mounted so that the impact will not damage them. Thus, the front wheel as well as the rest of the vehicle are securely held in place in the cargo bed of the transport vehicle with the need for additional securement as shown in FIG. 14 .
[0051] The motorcycle can also be further locked tighter onto the engagement mechanism by pushing or rotating the handlebars in a left to right motion. This pushes the left clip into engagement with the latches and holds it there while the right clip is then pushed into further engagement into its latch. This provides a simple mechanism using the motion of the motorcycle steering mechanism to tighten the motorcycle into even further engagement. It is to be understood that once the clips on the motorcycle are initially engaged in the latch mechanism, the motorcycle is locked securely and safely onto the transport vehicle. This additional engagement provides additional securement from movement of the motorcycle.
[0052] When the motorcycle is to be unloaded, pressure is applied to the foot release pedal 120 . This is easily done by a rider mounted on the motorcycle. This pressure causes the foot release pedal to pivot away from the yoke and moving the latch away from the clips. This disengages the clips and allows the motorcycle to be rolled away from the yoke.
[0053] In another preferred embodiment, the system includes the clip members mounted onto the motorcycle wheel for engagement into latch mechanisms on the yoke or bracket or other engagement mechanism.
[0054] Another preferred embodiment of the present invention mounts the clip members onto the frame of the motorcycle for engagement with a latch mechanism mounted onto the transport vehicle.
[0055] An additional preferred embodiment of the present invention mounts the clip members as described above onto the foot peg assembly of the motorcycle. The clip members engage in the latch assembly mounted on the transport vehicle.
[0056] The clip members may also be attached onto the handlebars of the motorcycle as well. The clip members then engage in the latch assembly on the transport vehicle.
[0057] This securement system can be used with many types of wheeled vehicles other than motorcycles, such as bicycles, wheelchairs, scooters, personal vehicles, carts, lawnmowers, small tractors, golf carts and other types of wheeled vehicles.
[0058] Another securement system 200 is shown in FIGS. 15 and 16 . This system is intended for use with snowmobiles and other types of recreational and business vehicles. This system includes base members 202 , 204 that are mountable to the base platform 20 . The base members may be adjusted relative to one another on the base platform to accommodate different sizes of vehicles. Tower members 206 , 208 are mounted on each of the base members. Flexible bracket 210 is mounted on tower member 206 . Locking bar 212 is secured to tower member 206 by flexible bracket 206 . The locking bar 212 may be pivoted relative to the tower member 206 as well as slid longitudinally.
[0059] Clip member 220 is mounted on the opposing end of locking bar 212 . Clip member is similar to clip members 130 or 150 discussed above. Latch 222 is mounted within tower member 208 . The latch 222 includes teeth 224 that engage the teeth of the clip member 220 . An aperture 226 is formed in the tower member 208 above the entry point of the latch 222 . The clip member 220 engages through the aperture 226 into latch 222 to lock the locking bar 212 in place over the skis of the snowmobile. This secures the snowmobile in the transport vehicle The latch 222 can be released from the clip member 220 by either a mechanism that releases the latch or a mechanism that moves the clip member away from the latch.
[0060] An alternative embodiment of the present system is used for all terrain vehicles. This embodiment is similar to the system 200 . A structural arm is mounted to the base platform 20 . The structural arm is extendable to be used on differing sizes of vehicles. The arm includes one free hinge and one ratchet hinge that allows it to be adjustable. The arm is locked in place by a clip that engages a latch on the system.
[0061] Each of these securing systems can also include locking systems that prevent the latches from being disengaged. This provides an anti-theft component to the systems.
[0062] These and other embodiments of the present invention are considered to be within the scope of the claimed inventions. | Systems for securing recreational vehicles to a transport vehicle quickly with a positive engagement mechanism. The systems are also designed to be quickly installed in the transport vehicle without causing any permanent damage to the transport vehicle. The systems may also be quickly changed out to allow other types of recreational vehicles to be transported as well. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application No. 60/514,477, filed Oct. 27, 2003, the disclosure of which is hereby incorporated herein in its entirety by reference.
FIELD OF THE INVENTION
The present invention generally relates to industrial dryers and in particular to a dryer employing a jet engine as a source of heat and air.
BACKGROUND OF THE INVENTION
Many different types of commercial and production endeavors require that a primary product produced and/or by-products thereof are to be dried at a stage after production process. Drying is generally needed in, for example, food processing, fertilizer production, sludge removal and processing, chip and bark processing, agriculture manure processing, and in the processing of distiller's grain, cotton, soybean hulls, mine tailings, coal fines, pellets and powders employed in nuclear waste water cleaning, and many other applications.
By way of example, equipment and systems used for drying or de-watering have been proposed over the years, and have met with varying degrees of success. Such equipment has taken the form of presses (particularly screw presses), centrifuges, gravity screens, and thermal dryers of varying configurations and energy sources. In many of these types of units, drawbacks have included high purchase and operating costs, low output or throughput levels, a lack of range of drying ability, production of “burned” end product, and emissions control problems. In order for a new equipment design or approach to find some level of acceptability, the equipment should address one or more of the above drawbacks, and provide superior features over existing designs.
Many products, in order to serve their intended purpose, are subjected to thermal drying processes in order to reach the level of dryness necessary for use of the product. Thermal drying is, however, a high cost operation. For cost reasons, many products can only be partially dried by known methods, as the price that such products are able to command does not allow for the cost of thermal drying. In many instances, these partially dried products could have a more beneficial use if the cost of drying were lower.
Many, if not most, refined products are thermally dried. There have been known efforts that attempted to develop a practical non-thermal air-drying system that would provide the necessary commercial production rates, but at a lower cost than that of thermal drying. The possibility exists that the end product would be of a higher quality, as well. It would appear that to date, known efforts have not yielded any truly promising systems or designs.
One object of the present invention is to provide an apparatus and method for achieving a high production rate, with drying comparable to known high-cost thermal drying, at a cost lower than that of known thermal drying equipment.
SUMMARY OF THE INVENTION
In view of the foregoing background, the present invention provides a process for producing a high quality dried product. Objects of the present invention may be achieved by employing a power plant, in the form of a turbofan jet engine, in an air-drying system that may use both thermal and non-thermal air-drying. The power plant may produce large quantities of air and heat, and operate with efficiency and an operating cost that provides a system suitable for use in situations for which existing thermal drying systems are too costly to operate.
One dryer system of the present invention may include a turbofan jet engine housed within an air distribution chamber that directs the exhaust air and bypass air from the jet into a material drying tube arrangement. Material to be dried may be injected into the tube and is carried in the airflow stream, where it is dried through a combination of thermal drying from the heat content in the engine exhaust, and by the kinetic energy of air flowing past the material traveling through the tube arrangement. The tube arrangement may include one or more types of physical impediments designed to retard the speed of the solids flowing in the air stream through the tube and/or to create turbulence in the air stream, so that the material is further dried as the high speed air passes by at a higher relative velocity.
The air distribution chamber may include a material preheating system in the form of a material feed belt and material flipper, wherein the material feed belt is thermally coupled to a jet exhaust air chamber, by sharing a common wall through which heat transfer is achieved, by way of example. For wetter materials that are initially in a mostly flowable form, a heat exchange coil can be employed, with the material being pumped through the coil, and the coil and material moving therethrough heated by the jet exhaust.
The drying tube arrangement may include one or more drying cyclones, which are preferably designed to further impede the flow of material, so as to increase contact with the faster airflow through the tube arrangement. One or more product extraction cyclones may be provided at the terminal end of the drying tube arrangement.
A material feed system embodiment may include a hopper for feeding material downwardly into rotating, spoked feed cylinders, which move the material from a position below the hopper into a path of the drying tube arrangement. At this position, the airflow through the drying tube arrangement draws the material from the cylinders into the drying tubes.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other aspects of the present invention will be more clearly understood from the ensuing detailed description of the preferred embodiments of the present invention, taken in conjunction with the following drawings in which:
FIG. 1 is a generally schematic side view of the apparatus according to one embodiment of the present invention;
FIG. 2 is a generally schematic view of the housing for the power plant according to an embodiment of the present invention;
FIG. 3 is a substantially schematic side view of the housing and feed system;
FIG. 4A and FIG. 4B are schematic views illustrating airflow through a housing in accordance with an embodiment of the present invention;
FIG. 5 is a schematic top view of a preheating and/or pre-drying subassembly in accordance with an embodiment of the present invention.
FIG. 6 is a side elevation view of a material flipper used in the FIG. 5 subassembly;
FIG. 7 is a perspective line drawing of the material flipper used in the FIG. 5 subassembly;
FIG. 8 is a schematic top plan view of an alternative embodiment of a preheating and/or pre-drying subassembly;
FIG. 9 is a schematic side view of the housing/chamber incorporating the FIG. 8 preheating and/or pre-drying subassembly;
FIG. 10 is a schematic side elevation view of a material injector subassembly in accordance with an embodiment of the present invention
FIG. 11 is a schematic top plan view of the FIG. 10 material injector subassembly;
FIG. 12 is a perspective view of a feeder cylinder for use in the FIG. 10 material injector subassembly;
FIG. 13 is a schematic side view of an alternative embodiment of a material injector subassembly;
FIG. 14 is a schematic cross-sectional view of the FIG. 13 material injector subassembly;
FIG. 15 is a schematic side elevation view of a feed wheel and auger suitable for use with the FIG. 13 material injector subassembly;
FIG. 16 is a schematic top plan view of the auger of the FIG. 13 material injector subassembly, coupled to a tube carrying drying air therethrough;
FIG. 17 is a schematic side elevation view of an alternative preferred embodiment of a drying apparatus in accordance with teachings of the present invention;
FIGS. 18A–D are schematic cross-sectional views of a drying tube assembly employed in an embodiment of the present invention;
FIGS. 19A–E are schematic cross-sectional views of a drying tube assembly employed in an alternative embodiment of the present invention;
FIGS. 20A , B are schematic cross-sectional views of a drying tube assembly according to an alternative embodiment of the present invention;
FIG. 21 is a schematic cross-sectional view of a drying cyclone which may be employed in accordance with one embodiment of the present invention;
FIG. 22 is a schematic cross-sectional view of a lateral drying elevator in accordance with a preferred embodiment of the present invention;
FIG. 23 is a schematic side sectional view of one lateral drying elevator;
FIG. 24 is a schematic top plan view of the lateral drying elevator and a flared inlet section of tubing;
FIG. 25 is a schematic view of a particle collider in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout, and prime notation is used to indicate similar elements in alternate embodiments.
Referring initially to FIG. 1 , components an air-dryer apparatus 10 according to the present invention are shown. A housing 12 includes an air distribution chamber 11 is provided at the front end of the apparatus 10 . The chamber 11 has mounted therein a jet engine 14 , such as a turbofan jet engine, by way of example.
The structure and operating characteristics of turbofan engines are generally known in the art. By way of example, a turbofan engine has a core engine and a bypass duct that directs most of the airflow around the core engine or turbojet, where it is ejected through a cold nozzle surrounding a propelling nozzle at the exit of the core engine. The bypass air is at a lower temperature and a relatively lower velocity, compared with the air exiting the core engine. As is well known in the aviation art, the use of bypass airflow makes the turbofan engine considerably more fuel-efficient than a pure turbojet engine.
The specific operating and performance parameters and characteristics of the turbofan engine to be used in the apparatus of the present invention will likely vary depending upon the size/capacity of each particular drying apparatus that is designed and engineered for a specific drying application. It is anticipated, however, that the design of a given dryer apparatus will be driven in part by selection of commercially available turbofan engines.
With reference again to FIG. 1 , the chamber 11 may be on the order of eight (8) feet in height, by 7.5 feet in width, by about twenty-four (24) feet in length. The chamber 11 illustrated in FIG. 1 has a hopper 16 and a preheating unit 18 disposed at an upper surface of the housing 12 . The preheating unit 18 is coupled to housing 12 such that heat generated by the turbofan engine 14 is transferred to the material to be dried, thereby elevating the temperature of the material and bringing the water or other liquids contained in the material to be dried closer to an evaporation point.
FIG. 1 also illustrates a drying tube assembly 20 into which the material to be dried is introduced. As discussed in greater detail later, the drying tube may include protrusions or other obstacles to slow the speed of the material to be dried relative to the air flow velocity of the jet air. Also shown in FIG. 1 are two drying cyclones 22 , 24 , in which the solid material is further slowed by protrusions disposed on the inside of the cyclone wall. The solid material may also be broken up by the protrusions. The material and airflow are carried through the two drying cyclones 22 , 24 to a separating cyclone 26 which separates the material from the air flow, and removes the material as a finished product from the lower portion of the cyclone 26 . The length or amount of drying tube to be employed, as well as the number and size of the drying cyclones to be used (if any), will be determined as the equipment design and layout is undertaken for each particular application in which the apparatus is to be used.
The schematic view of chamber 11 in FIG. 2 is provided to show one general positioning of the turbofan jet engine 14 in that chamber. The jet engine 14 may be mounted in an appropriate manner at one end of the chamber 11 , with the engine having its air intake at the outer periphery of the chamber. It is envisioned that, in one preferred embodiment, all or a portion of the intake air to the engine will be air that is recovered from the product separating cyclone at the terminal end of the process, and is treated prior to returning it to the inlet of the jet.
With reference to FIGS. 1 , 2 , 3 and FIGS. 4A and 4B , it can be seen that the air distribution chamber 11 , handles the high temperature, high velocity jet exhaust air, the jet engine bypass air, and an ambient air flow. The jet exhaust air may preferably be passed through a transfer pipe 30 into a hot air duct 32 , and passed upwardly into heating chamber 34 . Heating chamber 34 will transfer heat to and through an upper wall 36 of the heating chamber 34 . The engine exhaust air will then flow out of heating chamber 34 through 35 , into an air mixing chamber 38 , where the hot air is mixed with the engine bypass air, as well as, optionally, ambient air drawn into chamber 12 through one or more openings in the walls thereof. The vents can be controlled (i.e., opened or closed) as desired to regulate the pressure in heating chamber 34 , as desired or as may be required. In the construction illustrated in FIGS. 1–4 , the mixed air then passes through exit openings 40 ( FIGS. 4A , 4 B) disposed along each lateral wall 42 , 44 of chamber 11 , and into drying tube 20 ( FIG. 1 ), that is connected to each of the exit openings 40 .
FIG. 3 illustrates a preheating system 18 , having a wet material hopper or bin 16 , a feed belt 54 , made of stainless steel, by way of example, in consideration of the temperatures that will be experienced, and a series of material flippers 56 . In this embodiment, wet material is fed to bin or hopper 16 , and may be deposited therefrom onto feed belt 54 . Feed belt 54 runs along upper wall 36 of heating chamber 34 , and is either in contact with, or is spaced closely apart from, the wall 36 . As the feed belt 54 advances the material, the material flippers rotate to lift and flip the material on the belt, so that different surfaces of the material are exposed to the heat emanating from heating chamber 34 .
Once the material reaches the end of the belt, it has been pre-heated and/or dried to a desired extent, and the material is deposited into a material injection box 100 , which operates to introduce the material into the airflow of the drying tube 20 , in a manner that will be discussed in greater detail later herein.
FIGS. 5–7 illustrate in greater detail the construction of the preheating/predrying subassembly. Feed belt 54 may be driven by a motor and gearbox, illustrated schematically at 58 in FIG. 5 . The wet material bin or hopper 16 is disposed above the belt at its forward end. Each of shafts 60 is intended to show the position of the center shaft of a plurality of material flippers 56 . As seen in FIGS. 6 and 7 , the material flippers have a central shaft 60 and a plurality (three shown) of arcuate flipping blades 62 extending along a majority of the length of central shaft 60 . The length of the blades will preferably be determined to correlate to approximately the width of feed belt 54 . The central shafts 60 of the material flippers will be rotated by gearing, belt, or other drive coupling means, and will preferably be driven by either motor/gearbox 58 or by an independent motor or drive means. The material flippers 56 may be rotated in a direction counter to the feed direction of the belt such that the blades operate to scoop and lift material from the feed belt, and deposit the material substantially on a side which was not previously in contact with the feed belt. The number of, and spacing between, the material flippers will preferably be determined based upon the particular requirements and features of a given dryer unit.
Consideration should generally be given to the length of time which the material should stay in contact with the belt to be heated and dried, and how many times a flipping or agitation to expose other portions of the material to the heat will affect the desired drying results.
FIGS. 8 and 9 illustrate an alternative preheat design that takes advantage of a large thermal capacity of the jet engine exhaust. In the place of a feed belt 54 , a tubing or pipe construction, that will herein be termed a coil 70 , is provided in the heating chamber 34 . The coil 70 may preferably comprise multiple straight runs of pipe or tubing 72 connected at alternate ends in a serpentine-type manner, through which wet material may be passed to be preheated and/or partially dried.
It is envisioned that a coil may be used in place of the feed belt preheat subsystem particularly where the drying apparatus is designed to process wetter materials, such as those having an initial liquids content of greater than about 50%, or even higher. The high liquid-content (or low solids content) material may preferably be pumped from a holding tank 74 through the coil by a positive displacement pump 76 having a variable drive, of a type known to those of ordinary skill in the art. Where the preheating coil subassembly is employed with materials expected to exhibit higher viscosities, it is envisioned that other material delivery equipment of an injection type, such as a concrete pump, may be employed.
The coil may be mounted in the heating chamber 34 from the bottom, or may alternatively be suspended from the top of the chamber. FIG. 8 illustrates the tubing 72 running essentially parallel to the longitudinal direction of chamber 11 , with the inlet 78 disposed at one end, and the outlet 80 at the other. Variations to this, such as other positioning of the inlet and outlet, and tubing orientation (e.g., extending transverse to the longitudinal direction of the chamber), are seen as being design choices available to persons of ordinary skill in the art, and within the scope of the invention herein.
The material passing through the coil 70 is heated, such that the liquid may partially evaporate and become a separate phase from the wet solids material. It is also envisioned that the material emanating from the outlet could be introduced into a large volume, low pressure area or chamber, where the heated liquid would be permitted to “flash” off as a separate vapor phase, leaving the material considerably drier as it is introduced into the main dryer.
If it is desired to provide an air-dryer apparatus that could be used to process both high liquids content materials and higher solids content materials, both the coil subassembly within the heating chamber and the feed belt subassembly atop the heating chamber may be provided. Selection of which preheat system to use may then be made based upon the properties of the material being introduced.
FIGS. 10 , 11 and 12 illustrate one preferred embodiment of a material injector subassembly 100 , used to introduce a mushy material (either preheated/predried or not) into the main drying tube assembly 20 . This drying tube system, as illustrated, includes two sets of tubing 24 , 26 , which run along essentially identical paths (or mirror image paths), or, alternatively are joined together into a single tubing run at a desired point downstream of the material injector subassembly 100 . If smaller drying capacities or throughput are desired, the system may be designed to have only one tubing run, and a single injector in the injector subassembly. Alternatively, the system may be designed to run at half-capacity, wherein the material is fed to only one half of the material injector subassembly 100 .
Illustrated with reference to FIG. 3 , the material injector subassembly 100 may be located at an exit end of the feed belt subassembly, or at the exit to the preheating coil subassembly, when this equipment is present in place of feed belt 54 . FIG. 10 illustrates schematically that the solids material is fed from the preheater subassembly 102 into injector hopper 104 . Operating within hopper 104 are a pair of feeder cylinders 106 .
Feeder cylinders include a drum core 108 affixed to a drive shaft 110 . Extending radially outwardly from drum core 108 are a plurality of spokes 112 , and, attached at an outer periphery of the spokes is an outer cylinder wall 114 .
As illustrated with reference to FIG. 10 , the feeder cylinders 106 are coupled to a gearbox and motor assembly 116 , which operates to rotate the feeder cylinders 106 inside of hopper 104 . The material to be dried is deposited into hopper 104 , at a central portion thereof. The material may substantially fill each sector 118 formed by the spokes 112 extending between the drum core 108 and the outer cylinder wall 114 , as each sector rotates through the central portion of the hopper. The sectors 118 carry the material from the central portion of the hopper to a position at the outer portion of the hopper which is in alignment with, and open to, the two sets of tubing 24 , 26 of the drying tube assembly 20 .
As the sectors rotate into alignment with openings 120 in the hopper 104 , which openings are in alignment with and sealed to tubing sections, the material will, by force of the airstream flowing through tubing 24 , 26 , and/or gravity, exit out of the hopper and into the drying tube assembly 20 . As will be recognized from viewing FIG. 11 in particular, the material will be fed substantially continuously into the drying tube 20 , as the spokes are continuously advancing new material toward the openings 120 .
It will be recognized that this material injector equipment may be sized and operated for various feed rates or capacities, as an ordinary exercise in engineering. In a system, for example, in which drying tubing 24 , 26 has a 24″ diameter, the feeder cylinders 106 may preferably be six (6) feet in outer diameter, the drum core may be two (2) feet in diameter, thus resulting in the spokes 112 being 24 inches in length, correlating to the 24-inch diameter of tubing (see FIG. 11 ). With the material injector equipment so sized, and with the feeder cylinders 106 rotating at a speed of one (1) revolution every eight (8) minutes, the equipment is capable of delivering about 20 tons of material per hour into the drying tube assembly 20 .
With reference again to FIG. 10 , at the upper and lower portions of hopper 104 , appropriate seals 122 , 124 are provided that abut the upper and lower surfaces of the feeder cylinders 106 , so as to contain the material deposited in sectors 118 as the feeder cylinders turn. By way of example, the seals 122 , 124 , may preferably be made of Delrin®, which will also serve to lubricate the regions of contact between the cylinders and seals. Other materials may be employed, as will be recognized by persons of ordinary skill in the art.
An alternative preferred material injector subassembly 300 is illustrated in FIGS. 13–16 . In this embodiment, the housing 12 for turbofan engine 14 has a single, substantially horizontally oriented, tube 302 that is coupled to the drying tube assembly described earlier with reference to FIG. 1 . A hopper 304 is positioned to receive material from a preheat section, such as the feed belt system illustrated in FIG. 3 . Hopper 304 has one or more, and preferably two feed wheels 306 , 308 at a lower extent thereof. Material advances downwardly through hopper 304 , and is optionally agitated by a stirring bar 310 , and then enters sectors 312 of the vertically oriented rotating feed wheels 306 , 308 . It will be recognized, in viewing especially FIGS. 14 and 15 , that feed wheels 306 , 308 , have spokes extending radially from a central core, but are open at the periphery to receive the material therein. Thus, the construction may be similar to that of feeder cylinders 106 , but without using outer cylinder wall.
Feed wheels 306 , 308 rotate around a horizontal axis, and deliver material to an auger 314 having blades 316 , 318 canted to advance the material inwardly into tube 302 , and into the airstream exiting housing 12 . FIG. 15 illustrates that feed wheels 306 , 308 , and auger 314 may be mounted in a structure 320 that serves as an air lock, which prevents the air flowing through tube 302 from exiting out through the material injector subassembly 300 .
After material is dumped out of each successive sector 312 of the rotating feed wheels into auger 314 , auger rotates to advance the material inwardly toward tube 302 . As can be seen in FIG. 16 , tube 302 may be provided with a vane or vanes 322 , or other flow restrictor, to provide a venturi effect at the area where auger empties into tube 302 . The vanes may be disposed only at the area immediately upstream of the auger entry openings, or may be provided around the entire inner diameter of the tube 302 in this region.
FIG. 17 illustrates an alternative preferred variation on the unit illustrated in FIGS. 13–16 . In this embodiment, no preheater subassembly is provided, in that there are some potential applications for this apparatus which will not require a preheating stage. In this embodiment, the housing 400 will not generally serve as an air distribution box, and is provided principally for noise reduction, with appropriate sound insulation. Engine exhaust air and engine bypass air, as well as any ambient bypass air brought into housing 400 , are joined and sent directly into tube 402 , which is coupled to a drying assembly 410 .
In this embodiment, one preferred material injector subassembly may be the subassembly 300 described and illustrated with reference to FIGS. 13–16 . Material will enter tube 402 from an auger 314 , ( FIG. 14 ), and the material will become entrained in the airstream exiting housing 400 , and conveyed to the drying tube assembly. Material may be fed to the hopper 304 by a material conveyor or any other suitable means, by way of example.
By way of example, the above-described material injector subassemblies may be used where the material to be dried is either a mushy solid, a pretreated material that contains on the order of 35% solids, or superhydrated materials. Other feed systems, such as positive displacement pumps with variable drives may be used where the material is more fluid. Further, for higher viscosity materials, an injection system such as a concrete pump may be used.
By way of further example, once the material enters the drying tube assembly 20 , an objective in obtaining the maximum of a desired level of drying in the system is to maintain the air flow at as high a rate as the system will permit, while slowing down the material traveling through the drying tube assembly to a maximum extent possible, without causing clogging. This will permit both the thermal energy and the kinetic energy of the flowing air stream to operate to dry the material to a desired level.
One approach may involve simply using vertical tubing runs with an upward airflow, as would be the case in tubing section A in FIGS. 1 and 17 . The material resists becoming fully entrained in the upward airflow through tubes 24 , 26 , due to gravitational forces acting on the material. This approach is believed to be especially suitable for use when the material is at its wettest or heaviest condition, such as at a point shortly after being initially introduced into the drying tube assembly 20 .
Another approach may involve the use of physical obstructions within the drying tubing runs. FIGS. 18A–D , 19 A–E, and 20 A, B, illustrate some preferred examples as to how this approach could be implemented.
FIGS. 18A–D represent, schematically, cross-sections of a drying tube ( 24 or 26 ) at successive positions along the length of the tube. A plurality of rods 90 , made of steel or other material, may be positioned to protrude across a portion of the cross-sectional area inside the tube. The rods would preferably be positioned to be perpendicular to the flow direction, and, as seen in the successive views, may be rotated by 90° at each successive position, i.e., horizontal upper, vertical left, horizontal lower, vertical right, within the tube (as shown in FIGS. 18A–D ). Such a pattern may be repeated at several locations along the length of the tube.
The rods are positioned to impede the progress of solid materials passing thereby, by physically interfering with the passage of the material. It can be seen in viewing all of FIGS. 18A–D collectively that a central area of the tube may have no rods or other physical impediments such that the airflow may continue substantially unimpeded while various portions of the material will collide with the rods 90 as the material is advanced by the airstream. The rods may, alternatively, be positioned at angles, orientations, and positions that are not illustrated, as desired.
FIGS. 19A–E illustrate an alternative embodiment in which material flow is impeded by placement of physical obstacles. A plurality of flaps 92 are provided. The flaps 92 may be constructed of steel or other material, and may be secured to an inner wall of the tube by weldment or other suitable fastening means. Flaps 92 may individually occupy approximately 25% of the cross-sectional area of the tube, or any lesser or greater percentage, as desired. The flaps 92 may preferably be canted or inclined in the direction of airflow through the tube (see FIG. 19E ), such that the material impinging against each flap 92 will be allowed to slide free of the flap after being slowed by the collision with the flap. The positioning of the flaps 92 may be successively at different orientations relative to the previous flap. Thus, moving in the direction of airflow proceeding from FIG. 19A to FIG. 19D , the flaps may be positioned (in the orientation illustrated), in a top portion of the tube, a bottom portion, a left portion, and a right portion. Alternatively, the 90° rotation scheme used with rods 90 in FIGS. 18A–D could be employed. While the flaps 92 are shown as being somewhat fan-shaped or rounded, the shape is not seen as being critical to the proper operation of the flaps, and other shapes may perform equally as well.
By way of example, FIGS. 20A , B, illustrate yet an additional embodiment of a physical impediment to material flow. This embodiment employs a diverter flap 94 that is preferably mounted along a centerline of the cross-section of the tube, and is mounted by control arm 96 so as to be pivotable within the tube. As can best be seen in the cross-sectional view of FIG. 20B , the diverter flap 94 may be pivoted or rotated into varying positions to impede the flow of solid material (principally), to varying degrees. It is envisioned that a handle 98 extending from control arm 46 will be moved cyclically by an automated program and control means (not shown), such as solenoids and timers, to provide intermittent and varying degrees of blockage to one side of the tube, and then the other side of the tube. The handle 98 and diverter flap 94 are preferably positioned to lie in the same plane, such that the position of the handle at the exterior of the tube is representative of the position of the diverter flap 94 inside the tube.
With reference again to the schematic illustration of the system in FIG. 1 , drying cyclones 22 , 24 , may be employed as a further means of retarding material flow while permitting the airflow to remain at higher rates. FIG. 21 is a schematic cross sectional illustration of one embodiment of such a cyclone 22 , 24 . The airflow with entrained material enters the cyclone, preferably tangentially, through inlet 81 . The material spins in a circular motion in an upper portion 82 of the cyclone, while a center spool 83 collects a majority of the airflow, and conveys the air through air line 84 to a continuation of drying tubing 28 , 29 .
The upper portion 82 may have hardened teeth 85 protruding from the walls to slow and breakup the solid material while moving toward the bottom of the cyclone. A deflector assembly 86 extending underneath center spool 83 and extending outwardly to the walls of the upper portion 82 of the cyclone may be provided to aid in controlling air and material flow.
The walls 87 of cyclone 22 , 24 may be heated to enhance the drying/evaporation of the material coming into contact with the walls. Heating elements 88 may preferably be hot air chambers into which heated air from the airflow stream is passed, or any other type of heating element that will not significantly detract from the energy efficiency of the overall system.
As the material slows and falls to the lower portion of the cyclone, it exits through cyclone outlet 89 . Cyclone outlet 89 is coupled to the continuation of drying tubing 28 , 29 , and deposits the material into the air flow in the tubing. In one preferred embodiment, the region in which the material reenters the airflow stream is configured such that a venturi effect can be achieved in tube 28 , 29 as the material is introduced, or immediately upstream thereof. It is envisioned that it may be necessary to introduce additional, or makeup, air prior to the entry point where the material rejoins the airstream, as indicated by arrow B. The continuation of tube 28 , 29 , will convey the material further downstream, to either a second drying cyclone, or through additional drying subassemblies, or to the final material separating cyclone 26 .
The size of the drying cyclone will likely vary for each dryer apparatus that is designed and engineered for different applications. The cyclone or cyclones are employed, as noted, to increase the differential in speed between the main air flow and the material to be dried, and the size, including internal diameter and length, may be varied as a matter of routine engineering to achieve the desired effect.
With reference now to FIGS. 22–24 a lateral drying element (LDE) 500 may advantageously be used in the dryer apparatus of the present invention. The LDE 500 has an inlet 502 into a generally cylindrical chamber 504 .
As can best be seen in FIGS. 23 and 24 , the inlet is coupled to tube 28 or 29 by a flared section of tubing 27 , which flattens the cross-section through which the air and material must flow. The air and material are introduced into chamber 504 substantially tangentially to the chamber.
A wedge-shaped flow splitter 506 is provided at substantially the center of the longitudinal extent of chamber 504 . Flow splitter 506 extends along the wall of chamber 504 from a point substantially adjacent inlet 502 , and around approximately one-half to two-thirds of the inner periphery of chamber 504 .
The inlet and flow splitter will operate to divide the incoming air flow and material into two approximately equal flow streams, and the air and solid material will travel around the interior of the LDE several times before being advanced to outlet tubes 508 , 510 . As shown schematically in FIG. 22 , the outlet tubes are recombined downstream into a continuation of tube 28 or 30 .
Internal tubes 512 , 514 may optionally be suspended at the central area in chamber 504 , which will operate to more directly and more quickly direct principally an air flow of the incoming air and material toward the outlet tubes. One or more LDEs 500 may be positioned in the run of tubing 28 , 29 , either in place of, or in addition to the one or more drying cyclones. The LDE 500 increases the dwell time or retention time of the air and material in the dryer. One potential advantage of an LDE as compared with, for example, a drying cyclone, is that the unit may be oriented in any number of ways, as it is not ultimately wholly dependent on gravity to operate effectively.
With reference to FIG. 25 , a chamber 530 may be used in the air dryer apparatus of the present invention. This solids particle collision chamber 530 may preferably be used in tandem with an LDE 500 , in that the material leaving the LDE is preferably split into two material streams, shown schematically at 532 , 534 .
One collision chamber 530 may include a housing 536 and two inlet pipes 538 , 540 . The inlet pipes 538 , 540 are positioned to direct the two material streams 532 , 534 , toward one another, so that the solid particles will collide into one another. With the speed of the particles expected to be on the order of 400 mph, and thus having a high momentum, the collisions induced will cause the particles to break up. This results in a reduction of the average particle size of the solid material, which in turn increases the exposed surface area of the solids material. The increased surface area will enhance the ability of the flowing air stream to dry the material.
After the opposing material streams collide in housing 536 , these streams may preferably be united into a single stream flowing through outlet 542 . Outlet 542 will be coupled to the dryer tube system 20 , and the air stream and material carried therein will continue to a further component in the air dryer apparatus 10 .
Many modifications and other embodiments of the invention will come to the mind of one skilled in the art having the benefit of the teachings presented in the foregoing descriptions and the associated drawings.
Therefore, it is understood that the invention is not to be limited to the specific embodiments disclosed, and that modifications and embodiments are intended to be included within the scope of the appended claims. | An air dryer and process employs a jet engine for producing high quality dried products. A turbofan jet engine in an air-drying system uses both thermal and non-thermal air-drying. The turbofan jet engine is housed within an air distribution chamber for directing exhaust air and bypass air from the jet engine into a product drying tube, where it is dried through a combination of thermal drying from heat content in an engine exhaust, and by the kinetic energy of air flowing past the product traveling through the drying tube, that may include a physical impediment for retarding retard the speed of the product solids flowing in the air stream through the tube. | 5 |
BACKGROUND OF THE INVENTION
This invention relates to an oil type damper which relies on the viscosity of oil to brake the opening or closing motion of, for example, a lid in some type of machine.
In a cassette tape recorder or a video tape recorder, for example, there is used a damper for braking the sudden release motion of the lid of a cassette tape holder during the opening or closing of the tape holder for the purpose of abating impacts generated during the release motion.
The damper of this kind generally comprises a base adapted to be secured on the body of a given machine and a rotor accommodated rotatably within the base and adapted to receive the rotational opening or closing motion of a lid of a cassette holder, for instance. The methods for applying a braking action on the rotation of the rotor relative to the base are broadly divided into the frictional contact method and the method making use of the viscosity of an oil such as silicone oil. Of these two types, the oil type proves more desirable in terms of durability of the damper and the sensation perceived by the user during the operation of the damper.
Generally, the oil type damper comprises a cylindrical base, a rotor accommodated in the cylindrical base, and a number of other parts including a cap and a toothed wheel connected to the rotor. The fact that the number of component parts is large implies that the oil type damper is expensive. Moreover, the oil type damper is quite bulky and requires considerable time and labor to assemble. There is also a possibility that because of mismatching between component parts, the completed oil type damper will have unwanted play and consequently suffer from poor operational precision.
SUMMARY OF THE INVENTION
An object of this invention, therefore, is to provide an oil type damper which has a reduced number of component parts, employs a toothed wheel with the minimum possible thickness, and has no need for a boss on its cap and which, therefore, enjoys great ease of assembly, has such extremely small overall height that it can be fit in a space smaller than that required for a conventional oil type damper and has utility in an expanded range of applications.
The object described above is accomplished by providing an oil type damper which comprises a base having means to be secured on a given machine, a blind cylindrical wall formed integrally with the base, a cap fitted within the cylindrical wall and rotatably retained therein, a seal disk forming a housing in combination with the cap, and oil filling the housing.
In the oil type damper of this invention, a toothed wheel serving to receive the rotational opening or closing motion of the lid is formed integrally with the cap, the cap forms the housing in combination with the seal disk, and the cap is rotatably retained within the cylindrical wall. Owing to this arrangement, the oil type damper comprises a smaller number of component parts than the conventional counter-type having the toothed wheel and the cap formed independently of each other, requires less time and labor for its assembly, and has a very flat thin structure which allows it to be fitted into an extremely narrow space.
The other objects and characteristics of the present invention will become apparent from the further disclosure of the invention given in the following detailed description of preferred embodiments, with reference to the accompanying drawings.
BRIEF EXPLANATION OF THE DRAWINGS
FIG. 1 is a cross section of a conventional damper.
FIG. 2 is a front view of one embodiment of a damper of the present invention.
FIG. 3 is a cross section of the damper as viewed along line 3--3 of FIG. 2.
FIG. 4 is an explanatory diagram of a stationary disk in the damper of FIG. 2, illustrating a top view thereof in one half and a bottom view thereof in the other half.
FIG. 5 is a front view of a second embodiment of the present invention.
FIG. 6 is a cross section of the second embodiment of the damper as viewed along line 6--6 of FIG. 5.
FIG. 7 is an explanatory diagram of a shaft in a stationary disk in the damper of FIG. 5, illustrating a top view thereof in one half and a bottom view thereof in the other half.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 illustrates a conventional oil type damper. It comprises a blind cylindrical wall 1 formed integrally with a base adapted to be secured on a given machine by suitably known means, a cap 2 fixed in place by being snapped into an open end part of the cylindrical wall 1 and adapted to form a housing in combination therewith, a rotor 4 rotatably accommodated in the housing with a shaft 3 thereof extending through a central hole of the cap 2, a toothed wheel 5 fastened to the leading end of the shaft 3 extending out of the central hole of the cap 2, and a flexible seal disk 7 fitted around the shaft 3 and adapted to have the outer boundary thereof fixed in conjunction with the cap 2 to the cylindrical wall 1 so as to prevent oil from leaking out through the gap between the cap and the cylindrical wall. Since the conventional oil type damper comprises numerous component parts as described above, it requires much time for assembly. Since the toothed wheel 5 is set in place by being fitted on the shaft, it requires a certain degree of thickness. Since the cap is required to have a boss raised around its central hole for the purpose of preventing the shaft from producing unwanted play, the extent to which the overall height H of the damper can be decreased is limited. Thus, the portion in which the damper is secured is required to have a space larger than the overall height H.
This invention, therefore, forms the cap integrally with the toothed wheel to decrease the number of component parts and, at the same time, reduce the thickness of the toothed wheel to the fullest extent possible, and eliminates the boss of the cap to facilitate the assembly and decrease notably the overall height of the damper. Consequently, the oil type damper of this invention can be fastened even in a space too small for the conventional oil type damper. Thus, it will find utility in a wider range of applications. Now, the first embodiment of this invention will be described with reference to FIGS. 2-4.
By 11 is denoted a cap having a toothed wheel 12 formed integrally with the upper surface thereof. The outside diameter of a peripheral wall 11' of the cap 11 is greater than the outside diameter of the toothed wheel. The cap 11 is provided at the lower end of the outer surface of the peripheral wall thereof with an outwardly extended flange 13. As this cap 11 is pushed down into a blind cylindrical wall 15 formed integrally with a base 14, it advances past check claws 15' formed on the cylindrical wall while bending the check claws backwardly. The check claws then resume their original shape and position and rotatably retain the cap 11 inside the cylindrical wall 15 and prevent it from being drawn out upwardly. The base 14 includes means for fastening it to a machine with which it is functionally associated, i.e. the lid of a cassette holder. In this embodiment the fastening means are formed by at least one laterally extending apertured flange 14'.
Before this cap is set in the cylindrical wall, a stationary disk 16 is placed inside the cap and a seal disk 17 is attached fast to the lower side of the cap to cover the lower side. In this case, oil 18 is applied in advance to the opposite sides and the peripheral surface of the stationary disk 16 and/or the inner side of the cap, and the side of the seal disk opposed to the stationary disk.
In the embodiment illustrated in FIGS. 2-4, the stationary disk 16 is provided at the center thereof with a projecting shaft 19 of a circular cross section fitting the central hole of the seal disk and a shaft 20 of a non-circular cross section smaller than the profile of the projecting shaft 19 extending from the projecting shaft 19. The projecting shaft 19 has a depression 21. Into this depression 21 is fitted a protuberance 22 which rises from the center of the inner side of the cap.
The oil type damper of this embodiment, therefore, is assembled by setting in place within the cap the stationary disk coated in advance with oil and, at the same time, fixing the seal disk as by swaging to the lower surface of the cap, and pushing down the cap into the cylindrical wall with the direction of the non-circular shaft 20 adjusted to that of an identically shaped non-circular hole 23 formed at the center of the base 14 surrounded by the cylindrical wall. The non-circular shaft 20 of the stationary disk does not rotate because it extends into the non-circular hole of the base. When the cap is rotated in conjunction with the seal disk by the rotational input from the lid being damped, this rotation is braked by the oil intervening between the stationary disk, the inner surface of the cap, and the seal disk. Further since the cap has the protuberance 22 on the inner side thereof fitted into the depression 21 of the stationary disk 16, the cap, the stationary disk, and the base are concentrically positioned relative to one another and the inner wall of the center hole in the seal disk fits around the outer boundary of the projecting shaft 19 to form a seal for preventing oil leakage. When the oil is thermally expanded, the seal disk deforms in a swelling manner and absorbs the thermal expansion of the oil.
FIGS. 5-6 illustrate a second embodiment of this invention, in which a stationary disk and a shaft are formed separately of each other. The shaft 24 is provided at one end of the circular shaft portion thereof fitted into the central hole of the seal disk with a projecting part 25 of a non-circular cross section identical in shape with the cross section of the non-circular hole formed at the center of the stationary disk and at the other end of the circular shaft portion with a shaft portion 26 of an identical non-circular cross section extended into the non-circular hole of the base. Moreover, the cap is provided at the center of the inner surface thereof with a similar protuberance 22 and the shaft 24 is provided with a central depression 21 opening into the leading end of the non-circular projecting part 25.
The oil type damper of this embodiment, therefore, is assembled by setting the stationary disk within the cap, fixed the seal disk as by swaging to the lower surface of the cap, passing the shaft 24 through the central hole of the seal disk with the non-circular projecting part 25 adjusted to the non-circular hole at the center of the stationary disk, then adjusting the direction of the non-circular shaft 26 to that of the non-circular hole of the base, and pushing the cap down into the cylindrical wall. The oil type damper of this construction functions similarly to that of the preceding embodiment.
In the first embodiment, the oil type damper is made of a plastic material because the stationary disk and the shaft are formed integrally with each other. In this case, the stationary disk requires a certain degree of a thickness so as to have the required rigidity. In the second embodiment, since the stationary disk and the shaft are formed independently of each other, the stationary disk can be formed of a thin metallic plate and the overall height of the damper can be proportionately decreased, although the number of components parts is increased by one.
Optionally, the stationary disk may be provided with notches or a hole 16' as occasion demands.
The cylindrical wall may be in an annular shape as in the first embodiment or in an arcuate shape larger than a semicircle as in the second embodiment.
As described above, since the present invention forms the toothed wheel and the cap integrally with each other and causes the cap to form a housing in combination with the seal disk and enables the cap to be rotatably retained in the cylindrical wall, the number of component parts of the damper is smaller than that in the conventional damper which has the toothed wheel and the cap formed independently of each other. At the same time, the damper can be assembled with increased ease and the damper is finished in a very thin flat structure suitable to be fitted into a very narrow space. | An oil type damper comprises a cylindrical wall formed integrally with a base secured on a given machine, a cap set in place rotatably within the cylindrical wall and integrated with a toothed wheel, a seal disk forming a housing in combination with the cap, and oil filling the interior of the housing. The integration of the toothed wheel and the cap decreases the number of component parts, reduces the time and labor involved in assembly, and permits size reduction of the damper. | 4 |
TECHNICAL FIELD
The present invention relates to an industrial robot with an equalizing device, comprising a helical spring, and a method for balancing and use of the robot.
BACKGROUND
In industrial robots, comprising two robot parts pivotally arranged relative each other, powerful power consuming motors, which execute the pivoting of the robot, are required. Powerful power consuming motors are large, heavy and expensive, which commands a need of alternative solutions. One alternative is to supplement the robot with a device, which in the pivoting of the robot participates in the pivoting by absorbing the torque during the pivoting from a rest position/initial position, i.e. when the robot starts a work cycle. The concept pivoting from a rest position/initial position refers to a pivoting in a direction where the attraction of gravity contributes to the pivoting. The arrangement is of such a nature that it during the pivoting from the rest position generates a torque, which acts to restore the robot to its rest position/initial position and thereby helps/relieves the driving motor concerned during the lifting/pivoting back. The concept pivoting back to the rest position/initial position refers to a pivoting which counteracts and thereby compensates for the attraction of gravity, which pivoting in the following is designated balancing. The arrangement according to the foregoing is thus considered a balancing arrangement.
By arranging industrial robots with balancing arrangements, which help and relieve the driving motors, the robot manufacturer is not forced to install unnecessarily large and powerful motors in the robot. The opposite also applies, a powerful driving motor in combination with a powerful balancing arrangement increases the lifting capacity in the wrist of a large industrial robot. However, this leads to an increase in dead weight of both the motor and the balancing arrangement, which in turn calls for even bigger demands on the driving motor in question.
A balancing arrangement thus helps the motor concerned to counterbalance the applied handling weight as well as the present dead weight when pivoting occurs during operation of the robot. Balancing arrangements generally consist of weights, gas-hydraulic devices or spring devices in the form of helical springs, torsion springs and/or gas-based balancing cylinders. Apart from the counterweights the above mentioned devices are expensive, heavy and sensitive constructions. Gashydraulic devices are space demanding and are furthermore marred by density problems.
In helical spring-based balancing cylinders there is always a risk for obliquity of the piston rod in relation to the cylinder, the so-called drawer effect, which when it arises leads to wear of the cylinder device and drastically shortened life-time. The alternative with counterweights also results in disadvantages, because a robot with a counterweight can not be as compact and space-saving. The counterweight also restrains the freedom of movement of the robot. When the robot performs overly limited motion cycles, i.e. the robot is moving too little, problems with poor lubrication in the integral bearings arise.
The Japanese patent JP 10015874 discloses a robot arranged with a gravitation compensating spring device. The device comprises a spring housing, which includes a helical spring, a spring seat and a pull rod attached to the spring seat. Three guide pins are each arranged through a separate hole in the spring seat, which glides along the guide pins when the pull rod is pulled out and the helical spring by that is compressed. The aim is to prevent damage on the pull rod.
Industrial robots usually consist of a robot foot, a stand and a robot arm. The stand is rotatably arranged on the robot foot. The robot arm is pivotably arranged in a joint on the stand. The robot arm is composed of arm parts pivotably arranged in relation to each other. The robot arm comprises e.g. a first and a second arm part and also a wrist arranged with a tool attachment. The arm in its initial position/rest position is oriented with the first arm part almost vertical. When the robot is moving/in operation the arm pivots in relation to the stand at the same time as the arm parts pivots in relation to each other.
The total load on the robot consists of the applied handling weight in the wrist on one hand and the present dead weight of the robot on the other. In pivoting, the motor in question pivots the robot arm, and the the gravity acting on the arm loads/influences the balancing arrangement, whereby the balancing arrangement generates a torque.
The balancing arrangement then facilitates for the motor to pivot the arm back to its initial position/rest position. The pivot motor in question must thus, in pivoting the robot back, be able to handle a remaining torque, which is the sum of the moment from the total load as well as the oppositely directed torque generated in the balancing arrangement. The torque generated by the balancing arrangement and the power of the concerned pivot motor are thus in a state of dependence.
The development of industrial robots is moving towards ever larger robots. 10 years ago large robots managed to lift up to 100 kg with the wrist. The further development has made lifts of 200 kg possible and now there is a need to increase the lifting capacity in the wrist to extremely high loads of approximately 250 kg. With as high loads as that in the wrist, it is immensely important that a balancing arrangement works in the right manner.
In balancing arrangements comprising helical springs the helical spring is compressed or extended. When a helical spring is compressed there is always the risk that it deflects sideways i.e. bends/collapses. It must thus be prevented that the helical spring bends.
With loads on the robot of up to 250 kg in the wrist a balancing arrangement is forced to work with very large torque forces and is easily damaged. The damages usually originate through imbalance in the load of the balancing arrangement. In the case with a helical spring, spring housing, spring seat and a pull rod an imbalance in the load of the pull rod, so-called drawer effect, leads to obliquity of the pull rod in the spring housing, wear appears and the expected life-time of the balancing arrangement is reduced to an unacceptably low level. This leads to unwanted and expensive production interruptions. Furthermore there will also be extra unwanted cost for spare equipment.
In the arrangement according to the above mentioned Japanese patent the spring seat cannot turn axially in the spring housing. Load leads to large bending moments in the pull rod part in the spring housing, which results in very high strain in the construction, high surface pressures are generated and all this taken together results in the deflection of the pull rod.
Consequently, when producing industrial robots of the kind described above the need of a balancing arrangement arises, which can manage loads up to 250 kg and at the same time has as long expected life-time as the industrial robot. Thereby unwanted production interruptions and the need of spare parts is eliminated.
Those needs cannot be fulfilled by the balancing arrangement according to the above mentioned Japanese patent.
DESCRIPTION OF THE INVENTION
An industrial robot, comprising a manipulator with a control system, presents a robot foot, a stand and a robot arm with a wrist and a tool. The stand is pivotably arranged on the robot foot. The robot arm is pivotably arranged on the stand in a joint. The robot arm is composed of at least a first and a second arm part and also the wrist, all of which are pivotably arranged in relation to each other. A balancing arrangement is arranged to exert, when the robot is pivoted, a pulling force between a first and a second robot part and thereby to compensate for/balance the attraction of gravity when the relative position of the robot parts changes. The balancing arrangement is attached to the corresponding robot part with fastening devices.
The aim of the invention is to, arrange a helical spring based balancing arrangement on a robot as above, where the robot manages to lift 250 kg with its wrist without damaging the balancing arrangement. The aim of the invention is also to provide the robot with a balancing arrangement, which has as long life expectance as the robot. Consequently, the object of the invention is to improve, in a balancing arrangement according to above, the guiding of a pull rod in a spring housing and by that eliminate the risk of obliquity of the pull rod, the so-called drawer effect.
The solution according to the invention is characterized by the device specified in patent claim 1 with a balancing arrangement in the form of a helical spring based telescopic unit. A pull rod together with a guide tube form a telescopic unit., which is arranged between the robot parts and constitutes a support and a guide for the helical spring. When pivoting the robot the telescopic unit is extended or shortened at the same time as the guiding of the pull rod is improved in accordance with the independent method claim. Furthermore, the invention prevents that torque forces from the helical spring/springs spread to the telescopic unit, as the pull rod can pivot freely around its longitudinal axis, in accordance with the dependent claims. A robot according to the invention can be equipped with one or more balancing arrangements and preferably be arranged with a vertical robot arm in accordance with the independent utilization claim.
It is within the scope of the invention that the telescopic unit comprises more than two telescopic parts.
It is within the scope of the invention that the balancing arrangement according to the invention is arranged between arm parts in the robot, which are not directly connected.
It is within the scope of the invention that the robot is mounted in the ceiling or angularly mounted.
It is also within the scope of the invention that a robot is arranged in such a manner that the balancing arrangement is provided with spring seats, which are rigidly mounted on the respective attachments of the balancing arrangement, and that the telescopic unit extends coaxially through the spring set. When pivoting the robot both the telescopic unit and the helical spring unit are longitudinally pulled out.
In the solution according to the invention is also included that the robot is provided with one or more balancing arrangements.
It is within the scope of the invention that the spring housing is provided with aerating holes to eliminate pumping effects from the movement of the piston back and forth.
It is within the scope of the invention that a ring fastener is rotatingly arranged through a roller bearing.
It is within the scope of the invention that the described piston is replaced by another type of spring seat.
It is within the scope of the invention that the pull rod is a piston rod.
DESCRIPTION OF THE DRAWINGS
The invention will be explained in detail through a description of an embodiment of the invention in reference to the accompanying drawing, where
FIG. 1 discloses a balancing arrangement according to the present invention with the pull rod retracted.
FIG. 2 discloses a balancing arrangement according to FIG. 1 with the pull rod pulled out.
FIG. 3 discloses a balancing arrangement according to FIG. 1 without a helical spring and pull rod.
FIGS. 4 a and 4 b disclose a guide ring arranged in a spring housing opening.
FIG. 5 discloses an alternative embodiment of the invention.
FIG. 6 discloses an industrial robot provided with a balancing arrangement according to the invention.
DESCRIPTION OF AN EMBODIMENT
An industrial robot 1 ( FIG. 6 ) comprises a robot foot 2 , a stand 3 pivotably arranged on the robot foot 2 and a robot arm 5 connected to a joint 4 on the stand 3 , which robot arm 5 comprises a first and a second arm part 6 and 7 , respectively. The robot arm 5 is pivoted around a horisontal axis 4 a of rotation in the joint 4 . A balancing arrangement 8 , comprising a telescopic unit 9 and a helical spring unit 10 , is mounted on the robot 1 (FIG. 1 ). The helical spring unit 10 is coaxially arranged on the telescopic unit 9 . The balancing arrangement 8 comprises in its first end 11 a first attachment 12 for pivoted mounting on the stand 3 and in its second end 13 a second attachment 14 for pivoted mounting on the first arm part 6 .
The telescopic unit 9 comprises a first spring seat 15 and a second spring seat 16 between which the helical spring unit 10 is arranged (FIG. 2 ). The first spring seat 15 comprises a spring housing 15 a , which is arranged with a first end 17 , a cylindrical envelope surface 18 and also a second end 19 , provided with an opening 20 . A mounting 12 in the form of a first ring fastener 21 is arranged on the outside of the first gable 17 . The second spring seat 16 comprises a piston 22 , which is rigidly arranged at the first end 23 a of a pull rod 23 . The pull rod 23 together with the piston 22 are displaceably arranged inside the spring housing 15 a . The tube-formed pull rod 23 extends from the piston 22 , through a part of the spring housing 15 a and out through the opening 20 in the second gable 19 of the spring housing 15 a . The pull rod 23 is in its second end 23 b provided with an attachment 14 in the form of a second ring fastener 24 . The helical spring unit 10 comprises a spring set 25 in the form of two helical springs 25 a and 25 b which are arranged inside the spring housing 15 a between the piston 22 and the second gable 19 of the spring housing 15 a.
When the pull rod is pulled out of the spring housing 15 a the spring set 25 is compressed and thereby generates a spring force, which strives to extend the helical spring set and thus retract the pull rod 23 back into the spring housing 15 a . The generated spring force is used for the balancing.
Coaxially inside the spring housing 15 a on the inside of the first gable 17 a guide-tube 26 is arranged. The guide tube 26 extends inside the spring housing 15 a from the first gable 17 and almost to the second gable 19 . The guide tube 26 thus has a length smaller than that of the spring housing 15 a . The guide tube 26 has an outside diameter somewhat smaller than the inside diameter of the tube-formed pull rod 23 .
When the pull rod 23 is displaced along the guide tube 26 the pull rod 23 will glide with very good guiding and minimal friction along the guide tube 26 . This is accomplished by a first and a second bushing 27 and 28 . The first bushing 27 is rigidly arranged coaxially with and on the inside of the pull rod 23 and of an opening 29 in the spring seat 22 to form a longitudinal continous first guide surface 30 (FIG. 1 ). The second bushing 28 is rigidly arranged on the outside of the free end 31 of the guide tube 26 , in order to form a longitudinal second guide surface 32 on the guide tube 26 (FIG. 3 ). When displacing the pull rod 23 the spring seat 22 slides along the guide tube 26
When the pull rod 23 is displaced through the opening 20 in the gable 19 it slides telescopically on the outside of the guide tube 26 , which thus together form a telescopic unit 9 . The movement is stabilized by the pull rod 23 being supported by the first 30 and the second 32 guide surfaces, which are arranged at a distance from each other longitudinally. The first 30 and the second 32 guide surfaces guide the pull rod 23 with a slip fit, which together with the guide tube 26 form a rigid unit 33 between the first 21 and the second 24 ring fasteners (FIG. 2 ).
A guide ring 34 is rigidly arranged in opening 20 of the second gable 19 of the spring housing 15 a . The guide ring 34 is shaped with a third longitudinal guide surface 35 in the spring housing 15 a . The third guide surface 35 guides and acts as a slide bearing to the pull rod 23 in its movement out of and into the spring housing 15 a through the opening 20 (FIG. 2 ).
The possibility to compress the helical springs 25 a and 25 b arranged between the piston 22 and the second gable 19 of the spring housing 15 a determines how far the pull rod 23 can be pulled out from the spring housing 15 a . From the FIG. 2 it is clear that the guide tube 26 and the pull rod 23 are telescopically arranged within each other in sufficient degree to provide exact guiding and a good stability when the pull rod 23 is maximally pulled out. To secure that the pull rod 23 can be freely pivoted in the spring housing 15 a the second ring fastener 24 is rotatably arranged in the second end 23 b of the pull rod 23 through an angular ball bearing 36 .
The guide ring 34 is detachably mounted coaxially in the opening 20 of the gable 19 ( FIGS. 4 a and 4 b ). The function of the guide ring 34 is primarily to guide the pull rod 23 through the third guide surface 35 and secondarily to seal or mark off the spring housing 15 a . The guide ring 34 is easily replaceable. The guide ring 34 has an opening 37 , which is slotted without material loss. It can thus easily be slipped on the pull rod 23 and guided axially to its intended position in the opening 20 . A clamp ring 38 locks the guide ring 34 against axial displacement in the opening 20 . | Industrial robot arranged with a helical spring based balancing system, which is able to stand up to high load. | 8 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a fishing tool for fishing sucker rods, tubing, pipe, pumps, plungers, plugs, tubing stops, packers, tools, anchors, obstructions, etc. from downhole in a subterranean well, such as but not limited to an oil producing, gas producing, injection or disposal well. More specifically, the fishing tool of the present invention is strong enough to retrieve up to 12,000 feet of rod at once, is designed to reduce stress on the tool so that it can be reused multiple times, is serviceable because it can be disassembled and repaired in the field, and is versatile since it can be combined with bells, adapters and other existing types of rod fishing equipment and accessories to successfully retrieve a wide range of items from subterranean wells. One or more extension pieces can be added to the body of the fishing tool to effectively lengthen the tool and thereby increase its functionality.
[0003] 2. Description of the Related Art
[0004] Prior art fishing tools generally are of three types: tools that are overshot sockets, tools that bite and tools that are traps. An example of an overshot socket type tool can be found in U.S. Pat. No. 1,869,861 issued to O'Bannon. These socket type of tools are designed to telescope over the part left in the well and interlock therewith to permit withdrawal of the part from the well by the tool. One problem with the socket type tools is that they are designed to catch only on specific shaped items and therefore are limited in the types of items with which they can interlock. Also, the proper socket size must be used for the item to be fished. When the item shape and size is unknown, the operator must play a guessing game to find a socket that is the proper size to work. This often results in the several different sizes of sockets having to be run into the well before the proper socket size can be found. This is expensive in terms of time and manpower to try again and again to get the proper socket size for the specific situation. Furthermore the sockets have a tendency of slipping open when hardened, hard lined, brass, out of round or worn couplings are being fished. Lastly, the sockets generally last for only one or two uses and become worn easily.
[0005] The second type is a biter type tool. The biting type of tool is also known as a slip socket which should not be confused with the overshot socket type tool. An example of a biter type tool can be found in U.S. Pat. Nos. 1,620,382 and 1,620,383 issued to O'Bannon. These biter types of tools are designed to receive the part left in the well within biting members, such as collets, which can be moved inward to bite into the part to attach the part to the tool in order to permit withdrawal of the part from the well by the tool. One problem with the biter type tools is that they are attempting to bite into a hard surface and therefore can slip. Also, the teeth of the biter type tool are only designed to catch the round rod body section of a sucker rod, and not the other items such as the bead, wrench flat, pin shoulder, pin thread or coupling. Furthermore the teeth on the slips generally only last for one or two uses before becoming worn off. Therefore the slips need to be replaced often between uses.
[0006] The third type is a trap type tool. These trap type tools have a mechanism that traps the part inside the tool so that the part is captured therein and can be removed from the well with the tool. An example of a trap type tool is taught in U.S. Pat. No. 1,634,935 issued to Donnelly. In that patent, a hinged lift is provided within the tool so that after a shoulder of the part passes the lift, the lift springs back downward and traps the part within the tool. The lift of this invention is weak. Also, the tool is limited on the sizes of rods it can catch, limited on where it can catch the rod. The tool can become wedged and therefore limits the amount of pressure that this tool can exert when pulling an item from a well.
[0007] Another example of a trap type tool is taught in U.S. Pat. No. 1,720,692 issued to Reynolds et al. This invention employs a slip which is pushed upward within the tool as the item enters the tool and then slides back downward below a shoulder of the item as the item moves upward and away from the slip through an opening provided in the side of the tool. By sliding under the shoulder of the item, the slip traps the item within the tool as the tool is raised within the well, thereby allowing the item to be removed from the well by the tool.
[0008] The prior art mousetrap tools have several problems. First, because this type of tool is welded together, the barrel of this type of tool is weak and cannot withstand large lateral strains such as those imposed on it when the slip and the item being pulled are wedge between the walls of the barrel. Also, the top of this type of tool is also welded to the barrel portion and this creates another weak area where the tool will break. A further problem with this type of tool is that the side opening provided in the barrel of the tool is located above the shoulder of the slip, causing the item to create a sideways pull and torque moment on the tool as the item is pulled. This torque moment imposes stress on the tool that causes the barrel of the tool to split open and fail. Still a further problem with this tool is that it cannot be made in the sizes that are needed in the field. The geometry of the tool makes the walls too thin to hold the weight and tension of the rod string being pulled from the well. The rod string is also known as simply the rod, as working string, wire line tool string, or as tool string. A further problem with the tool is the way in which the slip is retained within the barrel of the tool. The slip is retained by shoulders that project into the barrel of the tool and retain the slip therein. There are two ways in which these shoulders are constructed, both of which are described in the Reynolds et al. patent. The first way is to mill slots into the interior surface of the barrel and then weld key stock into the slots to form the shoulders. The other way is to roll over the edges of two halves of the metal that will form the two halves of the barrel and then weld the two halves together to form the barrel with the rolled over edges forming the internal shoulders inside the barrel. The problem with these shoulders is that they can become bent and can prevent the slip from moving up and down within the barrel of the tool. When this happens, the tool is unable to attach to a rod and cannot fish rod out of the well. Because the shoulders of prior art tools are either welded within the tool or formed as an integral part of the barrel of the tool, once they become damaged, they cannot be economically repaired or replaced. This results in the tool no longer being functional and the tool must then be discarded.
[0009] Still a further problem with prior art fishing tools is that because their body is a fixed length and their bodies cannot be lengthened, they are unable to catch certain types of breaks, such as rod breaks where the broken length of rod exceeds the length of the body of the fishing tool, thus making it impossible for the fishing tool to be lowered sufficiently around the broken rod for the fishing tool to engage one of the protrusions on the well string which can be gripped by the slip of the fishing tool. Steel sucker rods are normally twenty five feet long and fiberglass rods can be up to thirty five feet long. There are no tools within the industry today that can catch fiberglass sucker rods or successfully catch polished rods that break in the body. Fiberglass sucker rods will simply tear if biter type tools are used and also sometimes fiberglass rods will flare out slightly at the end of the break, making it difficult for the rod body to fit into a biter type tool. Polished rods are the very top rod on a rod string. Therefore they are hardened to prevent wear which makes them very difficult to fish with biter type tools.
[0010] Because of all these weaknesses in this tool, it generally will only be a single use tool and it can only pull approximately 5,000 pounds of force without breaking.
[0011] The present invention is a trap tool that addresses the problems found in prior art fishing tools. The design of the present tool is much stronger, has less stress concentrations, and no bending moments or torque when pulling. The present invention has increased wall thickness, is made of single pieces of metal that are threaded together or otherwise removably connected together instead of being welded together, and is designed to create a straight upward pull on the tool instead of a sideways force when pulling an item out of a well. Therefore, it can retrieve up to approximately 12,000 feet of rods at a time without breaking or withstand approximately 40,000 pounds of tension. The present tool is durable, reusable, reliable, has a long service life.
[0012] The cross sectional geometry design of the present invention allows for critical sizes to be made and allows a variety of sizes to be offered. In fact, nine sizes of the invention will be made available to the purchasing public. This allows the invention to be constructed so that it can fish ¾ inch to ⅞ inch SH or slim hole couplings in 2⅜ inch tubing which is not possible with prior art tools. Slim hole couplings have the same outside diameter as the shoulder on the sucker rod whereas standard couplings have outside diameters that are larger than the shoulder of the sucker rod.
[0013] The present invention is a catch-all design that does not require the use of multiple sizes of sockets, such as required by overshot socket types of fishing tools. The present tool eliminates the need for oversized tools, sockets, grapples and overshots.
[0014] Further, this tool will catch hard lined couplings, fiberglass, worn or out of round couplings. This tool is provided with a threaded bottom end so that a variety of sizes of bells or adaptors can be employed with the tool. This tool can fish trashy rods from a well when an optional bottom piece with lip guide is used with the tool that assists in feeding the rods into the tool. The lip guide also allows the fishing tool to be utilized in horizontal wells. In horizontal wells the lip guide will guide the broken rod into the tool by rotating the tool from the surface. The lip will catch the rod and pull it over to the center of the fishing tool.
[0015] The design of the present tool allows it to be made with a smaller outer diameter which allows it to fit through crimped or bend tubing or tubing that is filled with scale or debris. Also the smaller diameter allows for fluid to more freely flow around the outer diameter of the tool. The design of the present tool allows the tool to be screwed apart so that additional features can be added to the tool and each part of the tool can be replaced or repaired in the field. Because the present tool is constructed of parts that thread together, the top portion of the tool can be removed and the tool can be attached to another tool, such as for example the O'Bannon biting type tool previously discussed, so that the two tools can be employed together, when it is desirable to do so.
[0016] Some operators will leave this fishing tool in the tubing during pumping. This is generally done when a rod is parted and the tool is deployed to fish the parted rod. Then, for some reason such as a stuck insert pump, time constraints, or for other reasons the tool is left in the tubing while latched onto the broken rod and the well is simply put back on to production with the tool being utilized as a coupler to mend the parted rod. Then the tool is retrieved the next time the well is pulled or when the tubing and or sucker rods must be pulled. This type of use will occur with this tool.
[0017] The present invention is also economical because it is reusable, field servable, and it is competitively priced. The present invention is also economical because it can produce a cost savings of approximately $10,000 to $30,000 per job on a deep well.
[0018] The present invention is also provided with one or more extension pieces that can be inserted in the middle of the tool to thereby extend the effective length of the body or barrel of the fishing tool so that the tool can be used to catch rod breaks. Specifically, by employing extension pieces in the present fishing tool, it is able to swallow the entire rod body length and to catch the enlarged section, bead or coupling located below the rod body break. This enables the present invention to catch fiberglass sucker rods that part in either the rod body or section area break, catch steel sucker rods that part in the body, and catch hardened polished rods that part in the body.
SUMMARY OF THE INVENTION
[0019] The present invention is a fishing tool for fishing sucker rods, tubing, pipe, pumps, plungers, plugs, tubing stops, packers, tools, anchors, obstructions, etc. from downhole in a subterranean well. The tool functions by trapping a broken sucker rod or other item to be fished out of the well within a barrel part of the tool's body by means of a combination of a movable slip provided within the barrel part and a side opening provided in the barrel part. The body of the tool is constructed of parts that are each machined from single pieces of metal stock and provided with threads so that the pieces can be secured together to form the body. The body is comprised of a top piece and a barrel piece, and normally also is provided with a bottom piece. A slip, preferable constructed of cast metal, is movably retained within the body. The slip serves to hold the rod within the barrel piece of the tool so that the rod or other item to be fished out of the well can be removed from the well by the tool.
[0020] The top piece of the body is constructed of a solid metal stock and is provided with male threads on its top end for securing the tool to a rod string and with male threads on its bottom end for securing the top piece to the barrel piece of the tool. The top piece is also provided with a fluid channel extending from the bottom of the top piece to a flattened wrench flat on the top piece in order to provide fluid communication through the top piece. The purpose of the channel is to allow liquids that are trapped either above or below the top piece to move through the channel as the tool is raised and lowered within the well tubing of the well.
[0021] The barrel piece of the body is constructed of hollow tube stock. The barrel piece is provided with female threads on its top end for securing the barrel piece to the male threads provided on the bottom end of the top piece and provided with female threads on its bottom end for securing the barrel piece to the bottom piece. Internally the barrel is machined to provide two parallel, longitudinally oriented grooves in which the slip is movably retained within the barrel. The slip is inserted into the barrel with ears of the slip inserting in the longitudinal grooves before the bottom piece of the body is secured to the barrel piece so that the bottom piece then captures the slip within the barrel portion when the bottom piece is attached to the barrel piece. Because the bottom piece secures the slip within the barrel, in order to replace the slip, the bottom piece is unthreaded from the barrel piece and then the slip can readily be removed from the barrel and replaced, if desired.
[0022] The barrel piece is provided with a side opening that extends down and terminates on its lower end so that its lower end is level with the upper shoulder of the slip when the slip is at its lowest position. The position of the lower end of the side opening relative to the upper shoulder of the slip at it's lowest position is important for the proper function of the tool because it insures that when a rod is attached to the tool, the pulling force is directed vertically on the tool and there is no sideways pull on the tool.
[0023] The body is normally also provided with a bottom piece, although, the bottom of the barrel piece can optionally be welded shut to permanently retain the slip within the longitudinal grooves and the bottom of the barrel piece can be internally beveled instead of being provided with female threads at its bottom end.
[0024] However, the normal configuration is to have a bottom piece attached at the bottom end of the barrel piece. The bottom piece is also constructed of hollow tube stock. The top end of the bottom piece is provided with male threads for engaging the female threads provided on the bottom end of the barrel piece in order to secure the bottom piece to the barrel piece. The bottom end of the bottom piece is enlarged externally to help in centering the tool within the tubing and is beveled internally to aid in feeding rod into the barrel of the tool.
[0025] Optionally, the bottom piece can be replaced by one of several sizes of existing bells. The bell can either be threaded directly onto the female threads provided on the bottom end of the barrel piece if the bell is provided with male threads that are compatible therewith, or alternately, can be secured to the barrel piece with an appropriate adaptor. The bell serves to guide the tool through larger size pipe interiors such as larger tubing sizes or production casing. The bell serves to guide the parted rod into the tool and allows the tool to stay centered in the pipe.
[0026] The slip is in a half moon shape, with its externally facing wall convex in shape and its internally facing wall concave in shape. Two ears are provided on the external surface of the slip for movable engagement with the longitudinal grooves provided internally within the barrel, as previously described. The bottom edge of the slip is beveled on its internally face in a half moon configuration to provide for smooth engagement of the slip with the rod as the rod enters the tool and pushes the slip upward. The top end of the slip is provided with a square shoulder against which an expanded surface of the rod or other item to be pulled will engage the slip as the tool is raised, as will be further described herein.
[0027] An optional slip can be employed instead of the standard slip. The optional slip is provided with a serrated or toothed shoulder on its top end instead of a square shoulder. The purpose of the teeth or serrations is to resist rotational slippage of the caught rod. The teeth are milled into a standard slip and are added to allow the tool to more easily be backed-off from downhole. Also, the teeth allow the tool to be more easily used when a rod on/off tool must be unlatched from downhole.
[0028] Depending on where the break in the rod string occurs, the shoulder of the slip on the present invention can engage any enlarged area of the broken rod string, including an upper or lower bead of a rod, an upper or lower shoulder of a rod, or a rod coupling.
[0029] One limitation of the present invention is that it is not able to catch on a straight rod if the rod is parted more than ten inches above a rod coupling. However, the present invention can be coupled with an existing biting type fishing tool, such as an O'Bannon slip socket, in order to additionally catch those types of breaks. As previously stated, the biting type of tool is also known as a slip socket.
[0030] In order to attach a biting type fishing tool such as the O'Bannon device to the present invention, first the top piece of the present invention is removed from the barrel piece and then the bottom piece of an O'Bannon type combination overshot socket device is removed from its top piece. Next, the barrel piece of the present invention is attached to the top piece of the O'Bannon type device. The barrel piece of the present invention may be attached to the top of piece of the O'Bannon type device either by directly threading the two parts together if their threads are compatible, or alternately, by employing an adaptor to secure them together if their threads are not compatible.
[0031] In order to extend the effective length of the body of the fishing tool, the top piece can be unthreaded from the barrel piece and one or more extension pieces can be threadably secured between the top piece and the barrel piece. Extending the effective length of the body of the fishing tool allows the tool to be used to catch a rod body break, on either a fiberglass rod, steel sucker rod or hardened polished rod. By adding one or more extension pieces to the fishing tool, the fishing tool can then swallow the rod body and catch the enlarged section, bead or coupling located below the rod body break.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] FIG. 1 is a side view of a fishing tool for fishing sucker rods out of a well constructed in accordance with a preferred embodiment of the present invention.
[0033] FIG. 2 is a front view of the tool taken along line 2 - 2 of FIG. 1 .
[0034] FIG. 3 is an enlarged view of the top piece of the tool associated with numeral 3 of FIG. 1 shown removed from the tool.
[0035] FIG. 4 is a front view of the top piece of the tool taken along line 4 - 4 of FIG. 3 .
[0036] FIG. 5 is a top view of the top piece of the tool taken along line 5 - 5 of FIG. 3 .
[0037] FIG. 6 is a bottom view to the top piece of the tool taken along line 6 - 6 of FIG. 3 .
[0038] FIG. 7 is a cross sectional view taken along line 7 - 7 of FIG. 4 .
[0039] FIG. 8 is a cross sectional view taken along line 8 - 8 of FIG. 4 .
[0040] FIG. 9 is a side view of the barrel piece of the tool associated with numeral 9 of FIG. 1 shown removed from the tool.
[0041] FIG. 10 is a front view of the barrel piece of the tool taken along line 10 - 10 of FIG. 9 .
[0042] FIG. 11 is a side view of the bottom piece of the tool associated with numeral 11 of FIG. 1 shown removed from the tool.
[0043] FIG. 12 is a bottom view of the bottom piece of the tool taken along line 12 - 12 of FIG. 11 .
[0044] FIG. 13 is a cross sectional view of the bottom piece of the tool taken along line 13 - 13 of FIG. 11 .
[0045] FIG. 14 is a front view of the slip of the tool associated with numeral 14 of FIG. 2 shown removed from the tool.
[0046] FIG. 14A is a perspective view of the slip of FIG. 14 .
[0047] FIG. 14B is a perspective view of an alternate slip.
[0048] FIG. 15 is a top view of the slip taken along line 15 - 15 of FIG. 14 .
[0049] FIG. 16 is a cross sectional view of the slip taken along line 16 - 16 of FIG. 14 .
[0050] FIG. 17 is a cross sectional view taken along line 17 - 17 of FIG. 10 .
[0051] FIG. 18 is a cross sectional view taken along line 18 - 18 of FIG. 10 .
[0052] FIG. 19 is a cross sectional view taken along line 19 - 19 of FIG. 10 with the slip shown in outline to indicate where it would normally be located.
[0053] FIG. 20 is a cross sectional view taken along line 20 - 20 of FIG. 10 .
[0054] FIG. 21 is a side view similar to FIG. 11 of an alternate bottom piece of the tool.
[0055] FIG. 22 is a bottom view of the alternate bottom piece of the tool taken along line 22 - 22 of FIG. 21 .
[0056] FIG. 23 is a cross sectional view of the alternate bottom piece of the tool taken along line 23 - 23 of FIG. 21 .
[0057] FIG. 24 is a side view of a bell for optional replacement of the bottom piece of the tool.
[0058] FIG. 25 is a cross sectional view of the bell taken along line 25 - 25 of FIG. 24
[0059] FIGS. 26-31 are perspective views of the steps involved in engaging a broken rod string located within a well with the tool.
[0060] FIG. 32 is a perspective view of the tool of FIG. 1 .
[0061] FIG. 33 is an enlarged view of a section of rod string to be fished with the tool.
[0062] FIG. 34 is a top view of the broken rod string taken along line 34 - 34 of FIG. 33
[0063] FIG. 35 is an enlarged side view of a tool that is constructed without a bottom piece.
[0064] FIG. 36 is an enlarged view of the tool and broken rod string from within circle 36 of FIG. 31 .
[0065] FIG. 37 is a side view of the fishing tool of FIG. 1 shown with an extension piece added between the top piece and the barrel piece.
[0066] FIG. 38 is a front view of the tool with extension piece added taken along line 38 - 38 of FIG. 37 .
[0067] FIG. 39 is a perspective view of a typical rod break in a rod string.
[0068] FIG. 40 is a perspective view showing the typical rod break of a rod string of FIG. 39 being caught by the tool with extension piece of FIG. 38 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0069] Referring now to drawings and initially to FIGS. 1 , 2 , 26 and 32 , there is illustrated a fishing tool 10 for fishing sucker rods 12 , tubing, pipe, etc. from downhole in a well 14 . The body of the tool 10 is constructed of parts or pieces 16 , 18 and 20 that are each machined from single pieces of metal stock and provided with threads so that the pieces 16 , 18 , and 20 can be secured together to form the body of the tool 10 . As shown in FIGS. 1 and 2 , the body is comprised of a top piece 16 and a barrel piece 18 , and normally also is provided with a bottom piece 20 . A slip 22 , preferable constructed of cast metal, is movably retained within the body, as will be more fully described hereafter. The slip 22 serves to hold the rod 12 within the barrel piece 18 of the tool 10 so that the rod 12 or other item to be fished out of the well 14 can be removed from the well 14 by the tool 10 .
[0070] Referring now to FIGS. 3 , 4 , 5 , 6 , 7 , and 8 , the top piece 16 of the body is constructed of a solid metal stock and is provided with male threads 24 on its top end 26 for securing the tool 10 to a rod string 12 and with male threads 28 on its bottom end 30 for securing the top piece 16 to the barrel piece 18 of the tool 10 . The top piece 16 is also provided with a fluid channel 32 extending from the bottom end 30 of the top piece 16 to a flattened wrench flat 34 on the top piece 16 in order to provide fluid communication through the top piece 16 . The purpose of the channel 32 is to allow liquids that are trapped either above or below the top piece 16 to move through the channel 32 as the tool 10 is raised and lowered within the well 14 .
[0071] Referring to FIGS. 9 , 10 , 17 , 18 , 19 and 20 , the barrel piece 18 of the body is constructed of hollow tube stock. The barrel piece 18 is provided with female threads 35 on its top end 38 for securing the barrel piece 18 to the male threads 28 provided on the bottom end 30 of the top piece 16 and provided with female threads 40 on its bottom end 42 for securing the barrel piece 18 to the bottom piece 20 . Internally the barrel piece 18 is machined to provide two parallel, longitudinally oriented grooves 44 in which the slip 22 is movably retained within the barrel piece 18 . These grooves 44 are milled with a rounded radius 46 at each of the edges, as shown in FIG. 20 . The rounded radius 46 is employed instead of a pointed or squared off edge because this reduces the stress concentration at this point, thereby allowing the tool 10 to be stronger. The slip 22 is inserted into the barrel piece 18 , with matching rounded ears 48 of the slip 22 inserting in the longitudinal grooves 44 before the bottom piece 20 of the body is secured to the barrel piece 18 so that the bottom piece 20 then captures the slip 22 within the barrel piece 18 when the bottom piece 20 is attached to the barrel piece 18 . Having the bottom piece 20 also makes the tool 10 stronger by eliminating a shear plane of a weld at this point.
[0072] Because the bottom piece 20 secures the slip 22 within the barrel piece 18 , in order to replace the slip 22 , the bottom piece 20 is unthreaded from the barrel piece 18 and then the slip 22 can readily be removed from the barrel piece 18 and replaced, if desired. The barrel piece 18 is provided with a side opening 50 . As shown in FIGS. 18 and 19 , the walls adjacent to the side opening 50 are parallel with each other, thus allowing a rod coupling to move outward through the side opening 50 , as will be more fully described hereafter. The side opening 50 extends down and terminates on its lower end 52 so that its lower end 52 is level with an upper shoulder 54 of the slip 22 when the slip 22 is at its lowest position. The slip 22 is shown in its lowest position in FIGS. 1 , 2 , 26 , 27 , 28 , 30 , 31 , and 36 . The position of the lower end 52 of the side opening 50 relative to the upper shoulder 54 of the slip 22 when the slip 22 is at its lowest position is important for the proper function of the tool 10 because it insures that when a rod 12 is attached to the tool 10 , the pulling force exerted on the tool 10 is directed vertically on the tool 10 and there is no sideways pull on the tool 10 .
[0073] Referring to FIGS. 11 , 12 , and 13 , the body is normally also provided with a bottom piece 20 that attaches at the bottom end 42 of the barrel piece 18 . The bottom piece 20 is also constructed of hollow tube stock. Male threads 56 are provided on the top end 58 of the bottom piece 20 for engaging the female threads 40 provided on the bottom end 42 of the barrel piece 18 in order to secure the bottom piece 20 to the barrel piece 18 . The bottom end 60 of the bottom piece 20 is enlarged externally to help in centering the tool 10 within the well casing or the well 14 and is provided with an internal bevel 62 to aid in feeding rod 12 into the barrel piece 18 of the tool 10 .
[0074] Optionally, as illustrated in FIGS. 21 , 22 and 23 , an alternate bottom piece 20 A can be employed that has a lip guide 64 provided in the bevel 62 of the bottom end 60 to facilitate guiding the rod 12 into the tool 10 , particularly when the rod 12 is bent or when the well 14 is filled with debris or scale. The optional lip guide 64 provides the tool 10 with the ability to rotate over the parted rod 12 . This is valuable because in most cases the parted rod 12 is up against the side of the inner wall of the tubing 100 . Sometimes it is freely against the wall and can easily move to the center when the tool 10 sides over it to catch it. But sometimes the parted rod 12 is bent or kinked over to the side of the wall, thereby making it more difficult to side over to the center. The lip guide 64 provides a gripping surface to rotate the rod 12 over toward the center so that it can more easily enter the tool 10 .
[0075] Also, as illustrated in FIGS. 24 and 25 , the bottom piece 20 can be replaced by one of several sizes of existing bells 66 . The replacement bell 66 can either be threaded directly onto the female threads 40 provided on the bottom end 42 of the barrel piece 18 if male threads 68 provided on the bell 66 are compatible therewith, or alternately, can be secured to the barrel piece 18 with an appropriate adaptor (not illustrated). The bell 66 serves to guide the tool 10 through larger size pipe interiors such as larger tubing sizes or production casing. The bell 66 serves to guide the parted rod 12 into the tool 10 and allows the tool 10 to stay centered in the pipe. Typical bells sizes are available for 3½ inch tubing, 4½ inch casing and 5½ inch casing, but other customized bells sizes can be obtained for up to 8⅝ inch casing.
[0076] As illustrated in FIG. 35 , alternately the tool 10 can be constructed without a bottom piece 20 . In this optional configuration, an alternate barrel piece 18 A is employed which has the longitudinal grooves 44 welded shut at the bottom end 42 A of the alternate barrel piece 18 A to permanently retain the slip 22 within the longitudinal grooves 44 . Also, the bottom end 42 A of the alternate barrel piece 18 A is provided internally with a bevel 70 to guide the rod 12 into the tool 10 instead of being threaded.
[0077] Referring to FIGS. 14 , 14 A, 15 and 16 , the slip 22 is in a half moon shape, with its externally facing wall 72 being convex in shape and its internally facing wall 74 being concave in shape. Two ears 48 are provided one on either edge of the external wall 72 of the slip 22 for movable engagement with the longitudinal grooves 44 provided internally within the barrel piece 18 , as previously described and illustrated in FIG. 19 . Also, the internal wall 74 of the slip 22 is provided at its bottom edge 76 with a half moon shaped bevel 78 to provide for smooth engagement of the slip 22 with the rod 12 as the rod 12 enters the tool 10 and pushes the slip 22 upward. As previously described, the upper shoulder 54 that is provided in the top end 80 of the slip 22 is square. The square shoulder 54 and provides a surface against which an expanded surface of the rod 12 , or other item to be pulled, will engage the slip 22 as the tool 10 is raised after the rod 12 has entered the barrel piece 18 and after the slip 22 has moved back downward to its lowest position, as will be more fully explained hereafter.
[0078] As illustrated in FIG. 14B , an optional slip 22 A can be employed instead of the standard slip 22 . The optional slip 22 A is similar to the standard slip 22 except it is provided with a serrated or toothed shoulder 54 A on its top end 80 A instead of a square shoulder 54 . The purpose of the teeth 82 or serrations is to resist rotational slippage of the caught rod 12 . To create the alternate slip 22 A, teeth 82 are milled into a standard slip 22 . The teeth 82 are added to allow the tool 10 to more easily be backed-off from downhole. Also, the teeth 82 allow the tool 10 to be more easily used when a rod on/off tool must be unlatched from downhole.
[0079] Some downhole pumps are not pulled out when the rods 12 are pulled out of the well 14 . These types of pumps are called tubing pumps. They are installed on the bottom of the tubing 100 and are retrieved from the well 14 when the tubing 100 is retrieved. However, rods 12 are still used. But there is a tool on the bottom of the rod string 12 called a sucker rod on/off tool. This on/off tool latches onto the top of the pump when the rods 12 reach it and stay latched on until it is unlatched. To unlatch from it, the work over rig operator must rotate the rod 12 which unlatches the rod on/off tool. In order for the sucker rod fishing tool 10 to be able to transfer this rotation to the rod on/off tool, it must resist rotational slippage between the tool 10 and the broken rod 12 . The teeth 82 on the top end 80 A of the alternate slip 22 A help resist this slippage.
[0080] In some cases insert tubing pumps will become stuck in the tubing 100 , i.e. in the seating nipple. Then the tool 10 may need to be backed off from. In this case the operator rotates the sucker rods 12 counter-clockwise to unscrew the rods 12 or clockwise when a back-off tool with left hand threads is utilized directly above the tool 10 . The tool 10 will also need to resist this rotation in order to be backed off from.
[0081] Referring to FIGS. 33 and 34 , there is illustrated a section of a typical rod string 12 showing a connection of an upper rod 12 U to a lower rod 12 L via a rod connector or coupling 12 C. The coupling 12 C shown in FIG. 33 is a standard coupling since its outside diameter is greater than the outside diameter of the shoulders 90 and 92 of the sucker rod. Beginning at the top of FIG. 33 and moving downward, the upper rod 12 U is provided with a rod portion 84 , an enlarged diameter bead 86 , a reduced diameter wrench flat 88 , and an enlarged diameter shoulder 90 . The female threaded rod coupling 12 C attaches to male threads (not illustrated) provided on a lower end of the upper rod 12 U so that the coupling 12 C abuts the enlarged diameter shoulder 90 of the upper rod 12 U when the upper rod 12 U is threaded together with the coupling 12 C, as shown in the FIG. 33 .
[0082] Still referring to FIG. 33 , and moving below the coupling 12 C, the lower rod 12 L is likewise provided with a male threads (not illustrated) provided on the upper end of the lower rod 12 L and with an enlarged diameter shoulder 92 that abuts the coupling 12 when the lower rod 12 L is threaded into the coupling 12 C, as shown in FIG. 33 . The lower rod 12 L then has a reduced diameter wrench flat 94 , an enlarged diameter bead 96 and a rod portion 98 . This illustration of this section of rod string 12 is provided to help illustrate the enlarged areas 86 , 90 , 12 C, 92 and 96 on a broken rod string 12 that can be caught by the present tool 10 .
[0083] Depending on where the break in the rod string 12 occurs, the shoulder 54 of the slip 22 on the present invention can engage an upper or lower bead 86 or 96 of a rod 12 , an upper or lower shoulder 90 or 92 of a rod 12 , or a rod coupling 12 C. One limitation of the present tool 10 is that it cannot engage the rod portion 84 or 98 of the rod 12 . However, if the rod 12 parts at the rod portion 84 of the rod 12 within ten inches or less distance from above the rod coupling 12 C the present tool 10 can still retrieve it at any of the aforementioned locations 86 , 96 , 90 , 92 , or 12 C. However, as is discussed hereafter, the present tool 10 can be attached with other existing fishing tools to address this limitation.
[0084] Referring now to FIGS. 26 , 27 , 28 , 29 , 30 , 31 , and 36 , the steps involved in fishing a rod 12 from a well 14 with the present tool 10 are illustrated. FIG. 26 illustrates the tool 10 being lowered within the well tubing 100 , casing or open hole and approaching the upper end 102 of a broken rod string 12 that is to be fished out of the well 14 .
[0085] FIG. 27 shows the tool 10 lowered further so that there is initial engagement of the upper end 102 of the broken rod string 12 with the bottom piece 20 of the tool 10 . This illustration shows how the internal bevel 62 in the bottom piece 20 guides the broken rod string 12 into the tool 10 .
[0086] FIG. 28 shows the tool 10 being lowered still further so that the tool 10 telescopically receives the broken rod string 12 within the tool 10 . This figure also shows the initial engagement of the upper end 102 of the broken rod string 12 with the slip 22 .
[0087] FIG. 29 shows the tool 10 lowered further, the broken rod string 12 received further into the tool 10 , and the slip 22 being pushed upward within the barrel piece 18 of the tool 10 by the broken rod string 12 .
[0088] FIG. 30 shows the broken rod string 12 moving into the side opening 50 provided in the barrel piece 18 which allows the slip 22 to slide downward within the barrel piece 18 past enlarged area or areas 86 , 96 , 90 , 92 , or 12 C of the broken rod string 12 until the slip 22 is located at its lowest possible position within the tool 10 . Once the slip 22 has moved into this position, the tool 10 is then ready to be raised.
[0089] Another way that the tool 10 can catch a broken rod sting 12 will be described. When the rod 12 enters the tool 10 , it pushes the slip 22 upward to the uppermost position of the slip 22 , i.e. at the top end of the grooves 44 . As the tool 10 travels further downward within the well 14 , the rod 12 travels upward within the tool 10 and along the slip 22 . The rod 12 then exits the side opening 50 as the tool 10 continues moving downward. The tool 10 continues to move downward until the broken upper end 102 of the rod 12 contacts the top piece 16 . When the end 102 contacts the top piece 16 , the tool 10 stops moving downward which signals the operator to begin raising the tool 10 within the well 14 . At this point the slip 22 is either located at its lowest most position or is still at the top end of the grooves 44 . If the slip 22 is still located at the top end of the grooves 44 , when operator starts to raise or pick up the tool, one of the edges 86 , 96 , 90 , 92 , or 12 C of broken rod 12 will engage the upper shoulder 54 on the slip 22 and drag it back down to its lowest position, i.e. to the bottom end of the grooves 44 . The top ends of the grooves 44 stop short of the upper end of the side opening 50 so that the tool 10 will function properly to allow the parted rod 12 to move upward beyond the top end of the grooves 44 and still exit through the side opening 50 .
[0090] FIG. 31 shows the tool 10 being raised with the broken rod string 12 secured thereto. FIG. 36 shows an enlarged view of the relative positions of the tool 10 and the broken rod string 12 illustrated in FIG. 31 . Referring to FIG. 36 , as the tool 10 is initially moved upward, the shoulder 54 of the slip 22 engages an enlarged area 86 , 96 , 90 , 92 , or 12 C of the broken rod string 12 that it previously slipped past. The enlarged areas 86 , 96 , 90 , 92 , or 12 C of the broken rod string 12 may not all exist on the broken piece left in the well and this depends on where the break takes place. Different sections in different instances will be caught depending on where the break takes place. Simultaneously, the same enlarged area 86 , 96 , 90 , 92 , or 12 C of the broken rod string 12 will also engage the lower end 52 of the side opening 50 of the barrel piece 18 . The lower end 52 of the side opening 50 of the barrel piece 18 and the slip 22 thus function together to capture the broken rod string 12 within the tool 10 and to keep the rod string 12 centered within the tool 10 . The shoulder 54 of the slip 22 and the lower end 52 of the side opening 50 of the barrel piece 18 are level at this time. This arrangement is important in that it prevents any sideway force from being exerted on the tool 10 as a pulling force is exerted on the tool 10 in order to pull the broken rod string 12 out of the well 14 .
[0091] One limitation of the present invention is that it is not able to catch on a rod 12 where the break is at the straight rod portion 84 or 98 of a rod string 12 . However, if the rod parts at the straight rod portion 84 of the rod 12 within ten inches or less from above rod coupling 12 C the present tool 10 can still retrieve it at any of the aforementioned locations 86 , 96 , 90 , 92 , or 12 C. However, the present invention 10 can be coupled with an existing biting type fishing tool, such as an O'Bannon slip socket, in order to additionally catch those types of breaks.
[0092] In order to attach a biting type tool such as the O'Bannon device to the present invention, first the top piece 16 of the present tool 10 is removed from the barrel piece 18 and then a bottom half of an O'Bannon tool is removed from its top half. Next, the barrel piece 18 of the present tool 10 is attached to the top half of the O'Bannon combination overshot socket tool. The barrel piece 18 of the present tool 10 may be attached to the top half of the O'Bannon tool either by directly threading the two parts together if their threads are compatible, or alternately, by employing an adaptor (not illustrated) to secure them together if their respective threads are not compatible.
[0093] Referring to FIGS. 37 and 38 , there is illustrated the fishing tool 10 which has had the top piece 16 disconnected from the barrel piece 18 and had one or more extension pieces 103 inserted between the top piece 16 and the barrel piece 18 , thereby extending the effective length of the body or barrel piece 18 of the fishing tool 10 . With the extension in effective length, the tool 10 can be used to catch broken rods 12 such as the one illustrated in FIG. 39 where the length 109 of the broken rod 12 , i.e. the length from the broken upper end 102 of the broken rod 12 to the bead 86 on the sucker rod 12 , would exceed the length of the barrel piece 18 alone. Each extension piece 103 is a hollow pipe or tube that is threaded at both ends. An adapter 104 is shown connecting the extension piece 103 to the barrel piece 18 of the fishing tool 10 . The extension piece 103 and adaptor 104 have outside diameters 105 and 107 , respectively, which are preferably approximately the same as an outside diameter of the barrel piece 18 of the fishing tool 10 . The inside diameter 106 of the extension piece 103 and the inside diameter 108 of the adaptor 104 are preferably approximately the same as an inside diameter of the barrel piece 18 of the fishing tool 10 .
[0094] FIG. 40 illustrates how the fishing tool of FIGS. 37 and 38 that has been effectively lengthened by the use of one or more extension pieces 103 is used to swallow the entire rod body length 109 of the broken rod 12 illustrated in FIG. 39 and to catch the enlarged section or shoulder 92 , bead 86 or coupling 12 C located below the broken rod 12 . By using one or more extension pieces 103 inserted into the body of the fishing tool 10 , this enables the tool 10 to catch fiberglass sucker rods that part in either the rod body or section area break, catch steel sucker rods that part in the body, and catch hardened polished rods that part in the body.
[0095] Further, although not specifically illustrated, the fact that the present fishing tool 10 threads together in pieces, this allows a variety of threaded accessories to be connected to the top, the bottom or in the middle of the tool 10 . These threaded accessories may include, without limitation, cameras, lead impression plates or blocks, adaptors, pipe extensions, bells, mill shoes, and other special ends and tools. While the invention has been described with a certain degree of particularity, it is manifest that many changes may be made in the details of construction and the arrangement of components without departing from the spirit and scope of this disclosure. It is understood that the invention is not limited to the embodiments set forth herein for the purposes of exemplification, but is to be limited only by the scope of the attached claim or claims, including the full range of equivalency to which each element thereof is entitled. | A fishing tool for fishing sucker rods from a subterranean well. The tool is a top piece, a barrel piece and bottom piece that all thread together. One or more extender sections are added by unthreading the top piece from the barrel piece and threading the extender sections therebetween to effectively lengthen the barrel piece and increase its functionality. The bottom piece retains a curved cast metal slip movable within grooves milled internally into the body. A lower end of a side opening provided in the barrel piece is level with an upper shoulder of the slip when the slip is at its lowest position. Optionally, the bottom piece can be replaced with a bell, lip guide, mill shoe, or other types of tools and the top piece can be replaced by a prior art fishing tool or other tools. | 4 |
BACKGROUND OF THE INVENTION
Considerable progress has been made in improving the fidelity of phonograph records. High-fidelity systems have attained a remarkable degree of perfection. Searching studies have been made of listening areas themselves.
It is curious to note that no parallel effort has been made to improve the holding and storage of records, while the slightest scratch on their grooves or the tiniest dust deposit causes spurious noise which decreases with the fidelity of the reproduction. From their earliest days, records have been slipped into jackets. The inevitable friction between the jacket and the record causes damage to the grooves and electrostatic charges which attract dust. Moreover, to remove a record from its jacket one must grasp its edge with at least two fingers in the area of the outer grooves.
Finally, records are often stored vertically, and their entire weight bears on the point where the record rests on its support. This can cause general warping of the record, causing listening imperfections which become more striking as reproduction improves.
SUMMARY OF THE INVENTION
The object of the present invention is an individual case for phonograph records, eliminating all the drawbacks inherent in the jackets presently used and able to shelter the record from all harmful factors to which it hitherto has been exposed: mechanical friction, eletrostatic charges, humidity and dust. The case made according to the present invention lends itself both to flat stacking and vertical storage of records. It enables them to be easily identified and selected, and moreover is an attractive and effective presentation display. Finally, it does not wear out, is easy to manufacture and is low in cost.
According to the essential characteristic of the invention, this case, made in thin molded synthetic material and with a square body and lid joined at one edge, is distinguished by the fact that its body and lid form the cooperating elements of two flush joints, keeping the case sealed and rigid and enabling the record contained therein to be centered.
Moreover, according to the invention, the body of the case forms the male elements of these two joints; the female elements are formed by the lid.
It is advantageous for the first joint, formed on the four rectilinear edges of the case, to stiffen the edges of its body and its lid, while the second joint, which is circular, determines the position of the record by its male part such as to pre-center it in the body of the case.
Another important characteristic of the invention consists of the fact that it includes a centering pin for the record, extending as far as the lid to keep it in place when the case is closed, and resisting its being crushed, in cooperation with the two flush joints.
BRIEF DESCRIPTION OF THE DRAWINGS
Other features of the invention will be apparent from the description hereinbelow of a preferred embodiment of the invention schematically represented without consideration of scale or proportions in the attached drawings, wherein:
FIG. 1 is a perspective view of the open case of the present invention;
FIG. 2 is a front vertical section of the case of FIG. 1 when shut and containing a record;
FIG. 3 is a front vertical section of the case of FIG. 1 showing the case open.
DETAILED DESCRIPTION
As shown in FIG. 1, the body of the case, generally indicated at 20, whose lid generally indicated at 2, is hingedly jointed to one edge thereof generally indicated at 21. This case is obtained by any appropriate process for molding plastic, for example, the hot-stamping process for polyvinyl chloride. One can see that its body 1 and lid 2 form the cooperating elements of two flush joints, respectively generally designated at 3 and 4; the male elements 5 and 6 of these two joints being formed in the body 1 of the case 20, the corresponding female elements 7 and 8 being formed on the lid 2. FIG. 1 clearly shows that the first joint 3 comprising the four rectilinear edges of the case, constitutes a ridge which stiffens the edges of the case, while second circular joint 4 constitutes a second stiffening ridge for the case 20. The male part 6 of the second circular joint 4 determines the space 9 for the record D placed therein.
Moreover, according to the present invention, a centering pin 10 is formed in the body 1 of the case 20. FIG. 2 clearly shows that this pin 10 extends upward after engaging the center hole of record D to the wall of lid 2 which it supports at its center, thus resisting crushing of the case when several such cases are stacked. This reinforcement to prevent crushing of the case is also effected by the two flush joints 3 and 4.
It may be seen that pin 10 is conical, and that it bears against the edge of the center spindle hole of record D placed in the case to exercise a slight holding pressure. The male part 6 of circular joint 4 constitutes a means of pre-centering the record, facilitating its placement in the case, and engagement of pin 10 in the hole thereof. Thus, it is in fact the pin which immobilizes the record from lateral movement within space 9.
To remove the record D from the case 20, a notch 11 is provided in the male part 6 of joint 4, preferably opposite one of the corners of the case 20.
To prevent air pressure from hindering opening of the case, whose surface is very large in relation to its thickness, at least one venting hole can be pierced at any point thereof. This venting hole is preferably placed at the top of pin 10 itself or the corresponding part of lid 2, as indicated at 12a and 12b.
It is known that it is often difficult to open plastic airtight boxes with a peripheral flush joint, for example, rectangular utility boxes. To remedy this disadvantage, and still according to the invention, the male part 5 of the first joint 3 is made discontinuous at the corners of the case 20, which facilitates the easy mating of the elements of this male part 5 with the corresponding female parts 7 of the lid 2 and the opening of lid 2.
However, it is important for the closed case to be quite rigid and, for this purpose, the female part 7 of the first joint 3 is preferably made continuous around the entire periphery of the case.
It is essential that the grooved area G of the record be protected from all contact and all friction. According to the present invention, this result is obtained by arranging, both in the body 1 of the case 20 and the lid 2, annular bearing zones 13 and 14 in the body 1 of the case 20, and 15 and 16 in the lid 2, these zones being the only ones in which the record contacts the case. These zones are spaced to engage the sides of record D in the portion of the surface at the beginning of the record containing no reproducible sounds, i.e., in the ungrooved periphery, and at the center of the record in the region corresponding to the printed label. This ensures that the grooved area G containing the recorded sounds to be reproduced from the record remains untouched. It will be observed that the circular ridges in the case thus created constitute additional stiffening elements for the case as a whole.
Opening will be facilitated by tabs 17 and 18 arranged respectively in the molding on the case 20 body 1 and on the lid 2, said tabs coinciding when the case is closed. They can also be used as thumb-tabs or filing markers.
The case in question can be made of transparent, opaque or colored material. In the first case the whole of the record it contains will be visible when the case is closed, and its circular central label will then be clearly legible.
However, it is also possible, for advertising or other purposes, to provide a circular label with a diameter equal to that of the record lodged in the annular recess made on lid 2 between supports 15 and 16 which will efficaciously center the label.
If, on the other hand, the case is made of opaque plastic, this annular zone of the lid 2 and possibly matching angular zone of the case's body 1 can both be embossed, engraved or printed with any inscriptions and markings. For this purpose it will be easy to provide an interchangeable central part in the mold in which it is cast, corresponding to the zone in question.
Experience has shown that a plastic satisfactory for forming the case itself does not always lend itself to making the hinged joint 21 between the body 1 of the case 20 and its lid 2. Forming the hinges themselves would make the case exorbitantly expensive. This is why, according to another advantageous embodiment of the invention, the joint between body 1 and lid 2 of the case 20 is provided by a simple band 19 straddling the body 1 and the lid 2, and made of an appropriate material able to withstand repeated folding. This band 19 is applied either by cementing with a suitable adhesive or by high-frequency electric welding.
It appears clearly from the description hereinabove that the protection provided for the record inside the case in question is perfect, whether the cases are stacked or on end. In the first case, the combined action of first and second joints 3 and 4, center pin 10 and supports 13, 14, 15 and 16 prevents the case from being crushed in any way. In the second case, the record never rests upon its edge. It is, in fact, suspended on center pin 10 when case 20 is not lying flat.
Moreover, the labyrinth composed of two successive joints 3 and 4, effectively prevents dust and moisture from reaching the record.
It is always easy to open the case due to the presence of tabs 16 and 17 and venting hole 12.
Of course many detailed modifications could be made to the various elements comprising the phonograph record case, a preferred embodiment thereof is represented here, without thereby departing from the framework of the invention. For example, in at least one of the angular zones of lid 2 between joint elements 7 and 8 an inflated part could be provided, formed in one piece with the lid, acting as an additional stiffener and able to constitute a pocket containing, for example, a record-cleaning cloth.
Finally, although the present specification relates especially to a phonograph record case, the invention also applies to construction of cases intended for packing and displaying other objects with the same main features as record cases (except, in certain cases, elimination of the center pin). Among such objects one may cite, for example, magnetic recording tape reels and movie film reels; articles of clothing such as neckties, shirts, scarves, and hose; miscellaneous objects such as eyeglasses, etc.
In these types of applications the case is also composed of a body and a lid engaging one another by a set of flush joints, the male elements of which are located on the case body and the female elements on the lid; the first joint is formed on all or part of the periphery of the case while the second is formed on the surface of the case and its shape can be adapted to the object to be enclosed, for example, circular (in the case of recording tape or film reels) or elliptical (in the case of neckties). | A case for enclosing phonograph records and the like is disclosed which provides for rigid support of the record and protection from scratching, dust and moisture without allowing the surface of the case to contact the record's grooved surfaces thereby damaging those surfaces. The molded case is formed of a lid and a body hingedly joined at one edge of each. The lid and body are molded to form flush joints and a centering pin together with annular bearing zones. Together these insure the record stays in position within the case, is protected from crushing force external to the case and is further protected from moisture and scratching. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to a beam or other panel supporting member which is specially constructed in a manner to accommodate built in lighting.
In recent years, solaria, large sky lights, glass canopies and arches, curtain walls, and other transparent structures have achieved growing architectural popularity. For example, it has recently become common practice for glass solaria to either be added on to existing commercial and residential buildings or built into newly constructed buildings. Sun rooms have been particularly popular in restaurants because they have considerable appeal to customers. Arch barrel walkways which are covered by curved transparent panels have also enjoyed considerable recent popularity.
Structures of this type normally include a number of glass or transparent plastic panels which are connected edge to edge by beams or other structural members which form the supporting framework of the structure. In commercial buildings, the structural members are often aluminum extrusions which take the form of rectangular tubes. The edges of adjacent panels are clamped or otherwise secured to and supported by the extrusions. The extrusions are arranged in a framework as rafters, wall studs or, in the case of arched walkways, as curved arches.
One of the major problems associated with this type of construction is the provision of lighting which is both functionally and aesthetically acceptable. Suspended lights or track lighting is often used, and difficulty is encountered in installing the light fixtures, hardware and wiring. Perhaps even more importantly, the light system creates a cluttered appearance which detracts appreciably from the aesthetic appeal of the overall structure.
SUMMARY OF THE INVENTION
The present invention is directed to a rigid structural member which is specially formed to provide both structural support for building panels and built in lighting capability. It is a particularly important feature of the invention that the lighting system is contained wholly within a channel which is formed in one edge portion of the structural member, thus avoiding clutter which could detract from the aesthetics of the structure. In addition, the lighting system is both functional and attractive in that it provides a continuous ribbon of light which exactly follows the contour of the structure (i.e., the ribbon of light curves along an arch member or extends straight along a straight rafter or wall stud). The light tube, all wiring, and all hardware are housed within a compartment which is closed off by an attractive diffuser lens, thus providing a clean and attractive appearance. At the same time, installation and maintenance can be quickly and easily carried out.
DETAILED DESCRIPTION OF THE INVENTION
In the accompanying drawing which forms a part of the specification and is to be read in conjunction therewith and in which like reference numerals are used to indicate like parts in the various views:
FIG. 1 is a perspective view of a solarium of the type which may employ structural members constructed according to the present invention;
FIG. 2 is a fragmentary sectional view on an enlarged scale taken generally along line 2--2 of FIG. 1 in the direction of the arrows; and
FIG. 3 is an enlarged perspective view of a clip member which is used to hold the light tube in place within the channel of the structural member.
Referring now to the drawing in more detail and initially to FIG. 1, numeral 10 generally designates a solarium which is attached to a vertical wall 12 of a building. The solarium 10 may be added onto an existing building or built as part of a newly constructed building. In any event, the room defined within the solarium 10 is enclosed by a plurality of glass panels 14 which form the walls and roof of the solarium. The panels 14 on the walls and roof are connected to one another edge to edge by rigid structural members 16 which form both the vertical wall studs and the inclined rafters of the solarium.
Referring now more particularly to FIG. 2, each of the structural members 16 is constructed in a similar manner and connects with the panels it supports in the same manner as the other structural members. Each structural member takes the form of an elongated aluminum extrusion 18 which may be a hollow rectangular tube. Each extrusion 18 is extruded into the desired shape and is cut to the required length. It should be noted that the extrusions may be straight members as shown in FIG. 1 or, in the case of covered canopies or barrel walkways, the extrusions may be arch shaped or they may take on another curved shape.
Each extrusion 18 has opposite side walls 20 and inner and outer walls 22 and 24 on its inside and outside edges, respectively. The transparent panels 14 are secured to the outer edge of each extrusion.
In the insulated, double glazed arrangement shown in FIG. 2, the panels 14 are provided in parallel pairs which are spaced apart from one another to provide a "dead space" between each pair of panels. It should be noted that the present invention is applicable to a single glazed system as well as to the double glazed system shown and described herein. At each extrusion in the double glazed arrangement, the panels in each pair are connected generally edge to edge with the panels in the adjacent pair. The edges of the inside panels 14 are received on pads 28 which engage the outer surface of wall 24. The edge portion of each outer panel is spaced outwardly from the edge portion of each inner panel by a spacer 30 which is interposed between the panel edges.
A plurality of internally threaded bosses 34 are formed integrally on the outer wall 24 of extrusion 18. A bolt 36 extends through a rigid retainer plate 38 and is threaded into each boss 34. The bolt head is received in a cavity formed in the retainer plate 38 which overlies a pair of pads 40 which fit against the edge portions of the outer panels 14. When the bolts 36 are tightened, the retainer plate 38 clamps pads 28 and 40 against the panels 14, with the spacers 30 sandwiched between the edges of the panels in the double glazed arrangement. In this manner, panels 14 are secured to and supported generally edge to edge on the structural member 16. A cover 42 may be secured to the retainer plate 38 in order to enclose the cavity and cover the bolt heads contained therein. The single glazed system is similar but lacks the second set of panels and the spacers 30.
In accordance with the present invention, the inner edge portion of one or more of the extrusions 18 may be provided with a channel 44 which opens inwardly and extends along the entire length of the extrusion 18. The channel 44 provides a recess in which a neon filled glass tube 46 may be contained and enclosed. The glass tube 46 is an elongated hollow tube held in place in channel 44 by a plurality of clips which are generally identified by numeral 48.
The configuration of each clip 48 is best illustrated in FIG. 3. Each clip includes a generally flat base plate 50 from which a pair of spaced apart legs 52 extend. The clips 48 are preferably constructed in a single piece and may be molded plastic. The legs 52 are flexible enough to be spread apart slightly to permit entry of tube 46 between them, and the legs resist their outward displacement and grip firmly against the opposite sides of the inserted tube. In this manner, tube 46 is held rigidly in place between the legs 52 of each clip, although the tube can be removed when it is necessary to replace or service it.
The opposite side edges of plate 50 fit closely within grooves 54 which are formed in extrusion 18 on opposite sides of the channel 44 adjacent to its closed end. The close fit of the plate edges in grooves 54 holds the clips securely in place within the channel.
Also formed on each clip 48 is a generally C-shaped channel 56 having its open side accessible for insertion and removal of a high voltage electrical wire 58 which fits closely within channel 56. The high voltage wire 58 is an insulated conductor which extends from one end of the elongated glass tube 46 to a transformer (not shown) located at the opposite end of the tube in the usual manner. The close fit of the wire 58 in channel 56 holds the wire securely in place and yet at the same time provides ready access to the wire and permits it to be removed for inspection and/or replacement.
The open side of channel 44 is covered by an extruded plastic diffuser lens 60 which serves to diffuse and evenly spread the light that is emitted by the neon tube 46. The exposed face of lens 60 is generally flat and is flush with the adjacent surfaces of wall 22 of the extrusion. A pair of lugs 62 extend from lens 60 into the channel 44 and are hooked in a snap fit with a pair of small ribs 64 which present shoulders which are engaged by the lugs 62. The lugs are hooked on the shoulders of ribs 64 in order to securely hold the lens 60 in place covering channel 44, thereby enclosing therein the neon tube 46, the clips 48 and the high voltage electrical wire 58.
The specially constructed extrusion 18 functions both as a structural member for supporting the panels 14 and as a housing for the lighting system. Structural members which are selected to provide lighting are constructed in the manner shown in FIG. 2, and the other structural members may have a conventional construction or may have the same construction and have their channels 44 covered by a suitable cover plate (not shown). The structural members which provide lighting may be on the ceiling, the walls or virtually any other desired location. However, the lighting is most often provided overhead in sun rooms, and the rafters or ceiling joists are thus most often constructed to provide the built in lighting.
When the neon tube 46 is energized by applying electrical current, it emits light which is diffused and evenly spread by the lens 60. Tube 46 and lens 60 extend continuously along the entire length of the structural member 16, and a continuous ribbon of light is thus provided along the structural member by the lighting system. The light emitted by the lighting system is functional in that it provides the light necessary for activities carried on within the solarium, and it is also highly decorative in that the ribbon of light extends continuously along and exactly follows the shape of the structural member.
It is again pointed out that the structural member 16 may be a straight member as shown for the rafters and wall studs in FIG. 1, or it may be an arch shaped member or a member which is curved or bent in virtually any other shape. The neon tube 46 can easily be made to follow the same contour as the structural member to which it is attached. As a consequence, the lighting system conforms exactly to the shape of the structure in which it is used. It should be noted that the panels supported by the extrusions are curved panels in the case of an arched canopy or other curved structure. It should also be noted that the panels need not be transparent and can be building panels of virtually any type. In addition, the panels can be connected to the extrusions by means other than the specific conventional arrangement disclosed herein.
The light system can be used to provide exterior lighting as well as interior lighting. A neon light tube is preferred because neon lights burn cool. It is possible in some applications for a florescent light tube to be used, although florescent lighting burns hot and is normally not as desirable as neon lighting for the majority of the applications contemplated by this invention.
It is particularly important that the light tube 46 and all hardware and wiring are housed wholly within the enclosed channel 44 which is formed in the extrusion 18. A clean and attractive appearance is thus maintained because the wiring and hardware is out of view. As a result, the lighting system of the present invention provides an uncluttered appearance in contrast to the suspended lights and track lighting which have typically been used in the past for similar applications.
From the foregoing, it will be seen that this invention is one well adapted to attain all the ends and objects hereinabove set forth together with other advantages which are obvious and which are inherent to the structure.
It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims.
Since many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense. | A structural aluminum extrusion which supports glass, plastic or other building panels and is also specially formed to house a lighting system. The panels are clamped edge to edge on one edge portion of the extrusion and a channel is formed in the opposite edge portion. The channel houses an elongate glass tube filled with neon. A special clip inserted in the channel holds the tube and the high voltage wire which supplies power to the tube. A snap on diffuser lens covers the channel and encloses the components of the lighting system. | 4 |
TECHNICAL FIELD
The present invention relates generally to equipment used in the production of hand-made quilts. Specifically, the present invention relates to an improved apparatus for holding an item of work during the quilting process.
BACKGROUND ART
The craft of producing hand-made quilts has long been an American tradition. Generally, a quilt is composed of three layers, a top layer, a layer of batting, and a layer of backing. The top layer of a quilt may be a single layer of fabric, but is more often composed of multiple pieces of fabric sewn together end to end to form a single layer. In some quilt designs, small pieces of fabric are sewn together in a mosaic or patchwork pattern, while in others, the top layer is made up of individual squares, with each square containing some sort of design (possibly embroidered or composed of multiple pieces of material of different colors).
Underneath the top layer of the quilt is the batting. Batting is a filling or stuffing material. Modern quilts generally utilize some form of synthetic fiber-fill material (generally in a sheet form) as batting, although other similar materials (including both natural and artificial materials) that provide bulk and insulation to the quilt may be used. Beneath the batting is the backing layer, which is usually a single layer of fabric. The backing and top layers of the quilt are sewn together along their edges to form a seam that encloses the backing.
The process of “quilting” refers to the particular manner in which the three layers are sewn together. In addition to being stitched together with seams around the edges, quilts are stitched together at locations in the middle of the quilt as well. These “interior stitches” extend through all three layers of material and generally form some form of decorative pattern that complements the design of the top layer.
As is also the case with embroidery, is it difficult to produce attractive “interior stitches” without some convenient way to hold the material, since the needle must pass through both sides of the work. In embroidery, it is common to use round or oblong “hoops” to hold and stretch the material being embroidered into a generally planar configuration that is easy to work with. These hoops generally consist of two concentric hoops of some rigid material (such as wood, plastic, or metal), where the material to be embroidered is stretched over the inner hoop, and the outer hoop is placed around the material and inner hoop to hold the material against the inner hoop. Often the outer hoop will have a screw or other adjustment mechanism to allow the inner diameter of the outer hoop to be adjusted to allow the hoop to be tightened around the material and inner hoop.
Traditionally, quilters have employed quilting frames that are a close analogue of the embroidery hoop to position and hold their work. These frames, like embroidery hoops, are generally constructed in some rounded or oblong shape, but in a larger size, so as to accommodate the larger dimensions of typical quilts. In addition, quilting frames are usually constructed so as to be free-standing, to support the large size and weight of typical quilts. The traditional round or oblong quilting frame shape, however, suffers from a number of disadvantages. First, traditional round or oblong frames provide a limited work area in relation to their size. Second, since most quilts are rectangular in shape, the traditional frames do not conform well to the shape of the quilt. As a consequence of these first two disadvantages, a quilter must frequently reposition the quilt within the frame as work progresses. A third disadvantage of the traditional design is that the durability of the traditional frame is limited by the fact that the round or oblong outer hoop must be flexed in order to tighten or loosen the frame; this places limitations on the strength and useful operating life of such a frame. What is needed, then, is a durable quilting frame that provides a larger and more useful work area than is possible with traditional quilting frames.
SUMMARY OF INVENTION
A preferred embodiment of the present invention provides a quilting frame apparatus that provides the user with a more efficient work area than is provided with traditional quilting frames. The quilting frame apparatus comprises concentric rectangular outer and inner frames. The outer frame is constructed from four elongate members attached in a mortise-and-tenon arrangement at each of its four corners and secured by wingnuts. The quilting frame may be adjusted at different angles to suit the user. The apparatus may also be folded for convenient storage.
The foregoing is a summary and thus contains, by necessity, simplifications, generalizations, and omissions of detail; consequently, those skilled in the art will appreciate that the summary is illustrative only and is not intended to be in any way limiting. Other aspects, inventive features, and advantages of the present invention, as defined solely by the claims, will become apparent in the non-limiting detailed description set forth below.
BRIEF DESCRIPTION OF THE DRAWINGS
The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, wherein:
FIG. 1 is a diagram of a quilting franc apparatus in accordance with a preferred embodiment of the present invention;
FIG. 2 is a diagram of a mortise-and-tenon joint used in the outer frame of a quilting frame apparatus in accordance with a preferred embodiment of the present invention;
FIG. 3 is a diagram depicting a mechanism used to adjust the viewing angle of a quilting frame apparatus in accordance with a preferred embodiment of the present invention;
FIG. 4 is a diagram depicting a quilting frame apparatus in a folded position in accordance with a preferred embodiment of the present invention; and
FIG. 5 is a diagram depicting a preferred method of use of a quilting frame apparatus in accordance with a preferred embodiment of the present invention.
DETAILED DESCRIPTION
FIG. 1 is a diagram of a quilting frame apparatus 100 in accordance with a preferred embodiment of the present invention. Quilting frame apparatus 100 provides a large rectangular work area, which allows a quilter to work for longer periods of time without the inconvenience of moving the quilt being worked on. Further, since many quilts are constructed of square or rectangular pieces, the rectangular shape provides a work area that better conforms to such rectangular quilt layouts than with conventional oblong quilting frames/hoops.
Turning now to the details of construction, the rectangular work area is defined by an outer frame, which comprises four removable outer pieces 102 , 104 , 106 , and 108 , and an inner frame 110 , the four sides of which are permanently connected together to form a rectangle. In a preferred embodiment, inner frame 110 is glued and nailed together from four elongated pieces of wood.
Outer pieces 102 , 104 , 106 , and 108 are connected at the corners using bolts and wingnuts in a mortise and tenon arrangement, as depicted in FIG. 2 . For example, outer piece 104 is fitted to outer piece 106 at mortise 105 (of outer piece 106 ) and secured with a bolt and wingnut 103 . Wingnut 103 and the other wingnuts connecting outer pieces 102 , 104 , 106 , and 108 serve the dual role of assembling outer pieces 102 , 104 , 106 , and 108 into a rectangular shape as well as allowing a user to adjust the tension with which the work (i.e., the quilt being worked on) is held. When quilting frame apparatus is in use, the work is held between the outer frame (outer pieces 102 , 104 , 106 , and 108 ) and inner frame 110 , as shown in FIG. 5 . In a preferred embodiment of the present invention, outer pieces 102 and 106 are approximately 45.5 inches in length, and outer pieces 104 and 108 are approximately 34 inches in length. One of ordinary skill in the art will recognize, however, that embodiments may be constructed in different sizes and with different dimensions, without departing from the scope and spirit of the present invention.
Since each of outer pieces 102 , 104 , 106 , and 108 must be attached individually to form the outer frame of quilting frame apparatus 100 , outer-frame supports ill extend outward from inner frame 110 to support outer piece 102 and outer piece 106 temporarily until these pieces can be joined with outer piece 108 and outer piece 104 to complete the outer frame.
Two adjustable rotating arms 112 and 114 connect inner frame 110 to support posts 120 and 122 at spacers 116 and 118 , respectively. Rotating arms 112 and 114 allow the user of quilting frame apparatus 100 to adjust the work/viewing angle of the quilt and also allow the user to fold up quilting frame apparatus 100 for storage, as depicted in FIG. 4 . Additional support for inner frame 110 is provided at support pins 124 and 126 , which rest at the apexes of support forks 128 and 130 , which are located at the tops of support posts 120 and 122 .
Additional structural stability is provided by cross beam 123 , which extends horizontally to connect the bases of support posts 120 and 122 . Corner braces 125 and 127 provide a secure and stable connection between cross beam 123 and support posts 120 and 122 .
An embodiment of the present invention is preferably constructed from a hardwood, such as ash or oak. One of ordinary skill in the art, however, that embodiments of the present invention may be constructed from other rigid materials, including non-wood materials, without departing from the scope and spirit of the present invention.
FIG. 2 is an exploded-view diagram providing additional detail regarding the mortise and tenon connections that connect outer pieces 102 , 104 , 106 , and 108 to form the outer frame. In FIG. 2 , outer piece 104 has a tenon 200 from which a bolt 202 extends outward. To connect outer piece 104 to outer piece 106 , tenon 200 is inserted into mortise 105 and secured at bolt 202 with washer 204 and wingnut 103 , as shown. Washer 204 should be of a sufficient outer diameter to extend over the edges of mortise 105 so as to securely fasten outer piece 104 to outer piece 106 .
FIG. 3 provides additional detail regarding the construction and operation of the mechanism used to adjust the viewing angle of quilting frame apparatus 100 . For simplicity, only one side of quilting frame apparatus 100 is depicted; the opposite side operates similarly. Inner frame 110 is supported by support fork 130 of support post 122 at support pin 126 . Inner frame 110 (and the outer frame that is attached to it) may pivot about support pin 126 . Rotating arm 114 is used to hold inner frame 110 at a constant angle, according to the user's preferences. Rotating arm 114 is connected to inner frame 110 at bolt and wingnut assembly 304 , which provides a second pivot point for inner frame 110 . Rotating arm is secured to support post 122 at bolt and wingnut assembly 302 , which extends through slot 300 in rotating arm 114 and which forms a triangle with support pin 130 and bolt and wingnut assembly 304 . The angle of inner frame 110 can be adjusted by positioning rotating arm 114 in different relative positions with respect to bolt and wingnut assembly 302 . Tightening bolt and wingnut assembly 302 then causes this angle to be fixed.
FIG. 4 is a diagram depicting quilting frame apparatus 100 having been folded into a compact configuration for storage. Support pins 124 and 126 are lifted out of support forks 128 and 130 , and the inner/outer frame assembly (comprising outer pieces 102 , 104 , 106 , and 118 and inner frame 110 ) is lowered by the rotation of rotating arms 124 and 126 about bolt and wingnut assemblies 402 and 302 . The inner/outer frame assembly is further positioned, by way of pivoting at bolt and wingnut assemblies 404 and 304 , so that the geometric plane defined by inner frame 110 is approximately parallel to the vertical direction. The inner/outer frame Assembly partially rests upon support posts 128 and 130 at spacers 116 and 118 .
FIG. 5 is a diagram depicting quilting frame apparatus 100 as configured for use during the quilting process. A quilt 500 is draped over inner frame 110 (not shown). Outer pieces 102 , 104 , 106 , and 108 are positioned over quilt 500 and connected so as to form an outer frame that holds quilt 500 securely against inner frame 110 . Quilt 500 is thus held by quilting frame apparatus 100 in a relatively taught fashion to permit the user of quilting frame apparatus 100 to have a rectangular and approximately planar surface of quilt 500 to work with, while also allowing the user access to the reverse side of quilt 500 , as is necessary for hand stitching.
According to a preferred method of use of the present invention, one makes the backing and batting for the quilt extend at least four inches beyond the edges of all four sides of the top layer of the quilt. A three-inch-wide strip of scrap fabric is then basted to all four sides of the top layer. This allows a user of quilting frame apparatus 100 to quilt to the edge of quilt 500 . According to this preferred method, one starts quilting in the middle of quilt 500 and quilts outward toward the edges of quilt 500 . To keep quilt 500 from touching the floor, the edges of quilt 500 are rolled up toward quilting frame apparatus 100 and tied with a string 502 , as shown in FIG. 5 .
The description of the present invention has been presented for purposes of illustration and description, and is not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiment was chosen and described in order to best explain the principles of the invention, the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated. | A quilting frame apparatus is disclosed, which provides a user with a more efficient work area than is provided with traditional quilting frames. The quilting frame apparatus comprises concentric rectangular outer and inner frames. The outer frame is constructed from four elongate members attached in a mortise-and-tenon arrangement at each of its four corners and secured by wingnuts. The quilting frame may be adjusted at different angles to suit the user. The apparatus may also be folded for convenient storage. | 3 |
TECHNICAL FIELD
[0001] This invention relates to the field of semiconductor materials, and in particular, to the growth of semiconductor crystals.
BACKGROUND OF THE INVENTION
[0002] An obstacle in realizing next-generation microelectronic and optoelectronic devices and optimal integration of these devices is found in lattice mismatches between different crystals of group III-V semiconductor materials. Generally, the lattice mismatch between a substrate and an epitaxial over-layer induces strains within the over-layer. This may lead to strain relaxation which can result in formation of material defects such as dislocations within the crystalline structure of the over-layer. FIG. 1 illustrates a mismatched over-layer 1 epitaxially grown over a substrate 2 , the boundary between the over-layer I and the substrate 2 being indicated with reference numeral 4 . As shown in FIG. 1 , the lattice constant associated with the over-layer 1 is different from the lattice constant associated with the substrate 2 , hence the term “mismatched over-layer”. Strain relaxation due to lattice mismatch is accommodated by the formation of mismatch dislocations 3 within the crystal. Defects within a crystal generally degrade the performance of devices made from the crystal, because such defects can scatter movement of carriers (electrons and holes) and can act as carrier traps and/or recombination centers. It is thus useful to provide means for growing a crystal over-layer which has different lattice constant from the substrate on which the over-layer is grown, in such a fashion that strain relaxation does not occur and mismatch dislocations do not form. FIG. 2 is an example of this, in which the structure of over-layer I is preserved and no mismatch dislocations are formed.
[0003] In the prior art, two main approaches are used to address the lattice mismatch problem and the strain relaxation it causes:
1) In a first approach, defects are confined in thick relaxed buffers so that the top active layer of a device can be of a different lattice constant from that of the substrate and is as defect free as possible. 2) In a second approach, thin compliant solid layers are bonded to foreign substrates and re-growth is performed.
[0006] However, these approaches still present performance degradation problems. A buffer layer of defects degrades the quality of the active layer on top of the buffer layer used for a device. In addition, thick buffer layers are not very suitable for device fabrication because high mesa or deep isolation implants are then necessary for device isolation, and can result in high leakage currents and low wafer yields. Further, procedures for implementing the second approach are rather complicated due to problems associated with wafer bonding, fabrication of thin layers (tens of Å in thickness) and re-growth on surfaces contaminated in the wafer-bonding and fabrication processes.
[0007] Hence, there is a need for a method of growing a crystal over a substrate such that mismatch dislocations are prevented from appearing within the crystal, even though the crystal and the substrate have different lattice constants.
BRIEF DESCRIPTION OF THE INVENTION
[0008] In accordance with this invention, compliant layers of group-V species are formed in situ, which distinguishes this invention from the prior art. Indeed, in this invention, formation of compliant layers does not require wafer-bonding and fabrication procedures performed outside of the growth chamber. Furthermore, crystals grown on top of compliant layers will not be strained and therefore, will not suffer strain relaxation which results in dislocation defects.
[0009] The present invention relates to processes and methods which facilitate the epitaxial growth of group III-V crystals of different lattice constants on top of each other. One object of this invention is to suppress strain relaxation associated with lattice-mismatched epitaxy. This is realized with a growth process that initially forms a substrate surface free of oxides. The growth process then deposits, at appropriately low growth temperatures, a layer of condensed group-V species and a mono-layer of constituent group-III atoms in order for the crystal over-layer to retain the condensed layer. Subsequently, the mono-layer is annealed at a higher temperature.
[0010] Finally, the bulk of the crystal over-layer is grown with the condensed group-V layer accommodating the strain build-up which occurs during the bulk growth.
[0011] In one example of the lattice-mismatch growth process, the substrate may be gallium arsenide, the condensed group-V species may be arsenic and the crystal over-layer to be grown may be indium arsenide (The lattice constant of indium arsenide differs from that of gallium arsenide by 7.2%).
[0012] In one aspect, the present invention relates to a semiconductor device comprising a substrate of a group-III/group-V material, a layer of a group-V material disposed over the substrate, a mono-layer of group-III atoms disposed over the layer of group-V material, and a layer of a group-III/group-V crystal epitaxially grown over the mono-layer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a schematic representation of a mismatched layer where some of the strain has relaxed by the formation of mismatched dislocations within the grown upper layer;
[0014] FIG. 2 is a schematic representation of how lattice mismatch is accommodated by a condensed layer of group-V species in accordance with this invention;
[0015] FIG. 3 is a schematic representation of the growth chamber illustrating desorption of surface oxides from the surface of the substrate;
[0016] FIG. 4 is a schematic representation of the growth chamber illustrating the deposit of a first layer of group-V species over the substrate;
[0017] FIG. 5 is a schematic representation of the growth chamber illustrating the deposit of a second layer of group-III species over the first layer of group-V species;
[0018] FIG. 6 is a schematic representation of the growth chamber illustrating the epitaxial growth of a crystal over the second layer;
[0019] FIG. 7 is a schematic representation of a semiconductor device in accordance with this invention; and
[0020] FIG. 8 is a schematic representation illustrating an exemplary embodiment of a semiconductor device in accordance with this invention.
DETAILED DESCRIPTION OF THE INVENTION
[0021] In accordance with this invention, the process or method of growing of a group III-V crystal on top of another group III-V crystal (substrate), without introducing lattice-mismatch defects, include the following steps:
[0000] Step 1 : Thermal Desorption Cleansing of the Substrate
[0022] In a preferred embodiment, the material forming the substrate upon which the epitaxial over-layer is to be grown may include GaAs, GaP, InAs or InP. As would be apparent to the skilled person, other group III-V compounds or crystals may be used as well.
[0023] In this step, and as illustrated by FIG. 3 , the substrate 7 is first heated inside a growth chamber 6 , to a temperature T s , where T s ranges from about 495° C. to about 600° C. Vapor 8 comprising group-V species (e.g., As 2 , As 4 , P 2 , P 4 or other group-V members) is introduced in the growth chamber 6 when the substrate 7 is heated. The pressure P of the vapor 8 introduced may range from about 0.004 pa to about 0.012 pa, which pressure P is larger than the vapor pressure P s of the substrate 7 at temperature T s . The temperature of the vapor 8 which is introduced in the growth chamber 6 , may range from about 300° C. to about 1000° C. The substrate 7 is then annealed under this over-pressure of group-V species vapor, at temperature T s , and desorption of surface oxides 9 from the substrate 7 takes place, with the surface oxides being removed from the chamber by pump 20 .
[0000] Step 2 : In situ Introduction of Condensed Group-V Species
[0024] As sown in FIG. 4 , an ultra-thin layer 11 of condensed group-V species (layer 4 of FIG. 1 ) which, in a preferred embodiment may comprise As 2 , As 4 , P 2 or P 4 , is then introduced in situ at a temperature T c , which temperature is lower than the optimal growth temperature for epitaxy of the crystal which is to be grown. Temperature T c may vary from about 30° C. to about 250° C. In this step, and as illustrated by FIG. 4 , a vapor 13 comprising a group-V species is introduced onto the surface of the substrate 7 by opening shutter 19 . When the temperature T s of the substrate 7 is appropriately low (between about 30° C. and about 250° C.), and the pressure P c of the group-V vapor 13 is adequate (about 0.004 pa to about 0.012 pa), condensation of the group-V species on the substrate 7 takes place. The thickness of the layer 11 of group-V species which condenses on the surface of the substrate 7 , can be controlled by varying the temperature T s of the substrate 7 . Indeed, the amount of desorption from the condensed layer of group-V species is dependent on the temperature. In other words, different thicknesses of the layer 11 can be achieved by varying the temperature T s . The temperature T s of the substrate 7 is preferably set such that the thickness of the layer of the group-V species falls into a range of several Å to a few tens of Å. The desired thickness of the layer 11 is achieved as soon as the temperature T s is reached, generally in a matter of seconds.
[0000] Step 3 : Deposit of a Mono-Layer of Group-III Atoms on the Group-V Layer
[0025] A layer of group-III atoms 12 is then deposited over the group-V layer 11 previously deposited on the substrate 7 , as illustrated by FIG. 5 . This layer 12 may be have a thickness ranging from one atom to a few atoms. In the preferred embodiment, the layer 12 is a mono-layer of group-III atoms. The layer of group-III atoms 12 may comprise In, Ga, Al or any combination of Ga, Al and In. The deposit may be made by opening, for an appropriate duration of time (between about 1 second and about 3 seconds) the shutter 14 of the furnace 15 containing a vapor of group-III atoms 17 . This duration of time may vary according to the geometry of the shutter 14 and furnace 15 , and the evaporation rate of the group-III atoms introduced. The vapor of group-III atoms is introduced at a temperature ranging from about 780° C. to about 1250° C. and at a pressure of about 5×10 −5 pa. In atoms are preferably introduced at a temperature of about 780° C., Ga atoms are preferably introduced at a temperature of about 900° C., and Al atoms are preferably introduced at a temperature of about 1200° C.
[0026] After introduction of the vapor of group-III atoms 17 in the growth chamber 6 , the vapor of group-III atoms 17 condenses on the surface of the substrate 7 above the layer of group-V atoms 11 , forming a mono-layer of group-III atoms 12 . At this stage the substrate 7 is kept at a temperature T d ranging from about 30° C. to about 250° C. and the pressure of the group-V vapor 13 which was introduced in step 2 is maintained around 0.008 pa. The mono-layer of group-III atoms 12 , is then annealed by raising the temperature of the substrate T d to a temperature from about 400° C. to about 580° C., under a pressure of group-V vapor 13 of about 0.008 pa. Such mono-layer of group-III atoms 12 has the property of changing the desorption tendency of the group-V species layer 11 lying underneath, and allows retention of the group-V species layer 11 during the annealing phase, which precedes the actual epitaxial growth of the crystal at an optimal growth temperature. The group-III atoms in the mono-layer 12 will seek lattice sites of a lower free energy during annealing, and will therefore form a propitious starting atomic plane for subsequent epitaxial growth. Because the bonding, between group-V molecules in the thin condensed layer 11 initially deposited, is much weaker than that between atoms of the solid crystal to be grown, the group-V molecules will relocate during the subsequent epitaxy to accommodate the lattice mismatch between the solid substrate crystal 7 and the desired solid crystal over-layer.
[0000] Step 4 : Epitaxial Growth of Crystal
[0027] Growth of bulk group III-V species layer 18 may then be initiated by opening again the shutter 14 of the group-IlI furnace 15 as illustrated by FIG. 6 . Such group III-V species layer 18 may include InAs, In x Ga 1-x As, In x Al 1-x As or GaP, but other group III-V species may be contemplated as well. In a preferred embodiment, group-V species and group-III species are introduced in the growth chamber with the ratio of the group-V flux to the group-III flux being maintained in the range of about 1.5 to about 3.
[0028] For the purpose of illustration, the method of growing a group III-V crystal on top of another group III-V crystal, without introducing lattice-mismatch defects, is described in the particular example where the substrate is GaAs, the thin-layer of group-V species is As 2 , the mono-layer of group-III atoms is indium, and the crystal epitaxially grown is InAs. This method comprises the following steps:
[0000] Step 1 : Thermal Desorption Cleaning of the Substrate
[0029] In one embodiment of this invention, a GaAs substrate 7 is heated to about 600° C. and annealed for about 10 minutes under an As 2 vapor 8 at a pressure of about 0.008 pa, which pressure is larger than the vapor pressure of GaAs at 600° C.
[0000] Step 2 : In situ Introduction of Condensed Group-V Species
[0030] In this step, the temperature of the substrate 7 is first allowed to drop or is cooled to about 110° C. while the substrate 7 is subjected to an As 2 vapor pressure 13 of about 0.008 pa, so that a condensed layer 11 of As 2 is formed on the surface of the substrate 7 . The As 2 condensed layer 11 is then thinned down to the desired thickness, which thickness is preferably around several tens of Å or less, by then raising the temperature of the substrate 7 to about 250° C.
[0000] Step 3 : Deposit of a Mono-Layer of Group-III Atoms on the Group-V Layer
[0031] In this exemplary embodiment, the desired number of group-III atoms per surface area forming the mono-layer is approximately 6.5 e14 cm −2 . The shutter 14 of the furnace 15 is opened to introduce indium vapor 17 at 790° C. so that a mono-layer of indium 12 is deposited over the condensed As 2 layer 11 . When the group-III flux incident on the growth surface is about 6.5 e14/2.2 cm −2 s −1 , the shutter is preferably opened for 2.2 seconds in order to obtain the desired mono-layer of 6.5 e14 cm −2 group-III atoms. The substrate temperature is kept at about 250° C. while still being subjected to a pressure of As 2 vapor 13 of about 0.008 pa. The temperature of the substrate 7 is then raised to about 400° C. while the As 2 pressure 13 inside the growth chamber is maintained around 0.008 pa. The mono-layer of indium 12 is annealed when the substrate temperature ramps from about 250° C. to about 400° C. After this step, the conditions are propitious for epitaxial growth of InAs, without introducing dislocation defects due to lattice mismatch between the GaAs substrate and the InAs crystal.
[0000] Step 4 : Epitaxial Growth of Crystal
[0032] Growth of bulk InAs layer 18 may then be initiated by reopening the shutter 14 of the indium furnace 15 . The temperature is maintained at the optimal epitaxial growth temperature for InAs, between about 400° C. and about 450° C., while the ratio of the group-V flux to the group-III flux introduced, is preferably maintained around 2.5.
[0033] In the methods described above, the substrate 7 may be heated in any way known in the art, including through contact heat diffusion or radiation heat transfer. In one embodiment, a tantalum filament is heated up by inducing an electrical current through the filament. The filament is preferably disposed adjacent the back of the substrate, such that the heated filament radiates energy to the substrate. Heat shields may be disposed under both the substrate and the filament in such a way that most of the heat radiated by the filament is efficiently transmitted to the substrate.
[0034] A pump 20 may be used throughout the steps of the methods of the present invention in order to rid the growth chamber of unwanted residual vapors, including surface oxides.
[0035] In another aspect, the present invention relates to a semiconductor device as shown in FIG. 7 . The semiconductor 20 comprises a substrate 7 of a group-III/group-V material, a layer 11 of group-V material disposed over the substrate 7 , a mono-layer 12 of group-III atoms disposed over the layer 11 , and a layer 18 of epitaxially grown group-III/group-V crystal disposed over the mono-layer 12 . In an exemplary embodiment of the semiconductor device 20 shown in FIG. 8 , the substrate 7 is GaAs, the layer 11 is As 2 , the mono-layer 12 is In, and the crystal 18 is InAs.
[0036] Even though the present invention is described in connection with specific group-III and group-V elements, any combination of these elements may be used.
[0037] Having described the invention in connection with certain embodiments thereof, modifications will certainly suggest themselves to those skilled in the art. As such, the invention is not to be limited to the disclosed embodiments except as required by the appended claims. | The present invention relates a method for epitaxial growth of a second group III-V crystal having a second lattice constant over a first group III-V crystal having a first lattice constant, wherein strain relaxation associated with lattice-mismatched epitaxy is suppressed and thus dislocation defects do not form. In the first step, the surface of the first group III-V crystal (substrate) is cleansed by desorption of surface oxides. In the second step, a layer of condensed group-V species is condensed on the surface of the first group III-V crystal. In the third step, a mono-layer of constituent group-III atoms is deposited over the layer of condensed group-V species in order for the layer of constituent group-III atoms to retain the condensed group-V layer. Subsequently, the mono-layer of group-III atoms is annealed at a higher temperature. In the fourth step, bulk of the second group III-V crystal is grown with the condensed group-V layer accommodating the strain build-up which occurs during the bulk growth. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of Provisional Application No. 61/048,714 filed on Apr. 29, 2008, the content of which is herein incorporated by reference in its entirety.
BACKGROUND
1. Technical Field
The present disclosure relates to image analysis, and more particularly to systems and methods for identification of targets in multispectral imaging data.
2. Discussion of Related Art
Multispectral fluorescence imaging techniques, such as fluorescence microscopy and bioluminescence, provide a mechanism for visualizing and studying molecular targets both in vitro and in vivo. These optical imaging technologies have several biomedical applications, including the diagnosis and monitoring of disease, studying the effects of drug candidates on target pathologies, and the discovery and development of biomarkers.
In multispectral fluorescence imaging, multiple targets of interest (TOIs) in a specimen are each specifically labeled with a fluorophore, which is a fluorescent molecule. The specimen is illuminated with light of a specific wavelength(s), which is absorbed by the fluorophores, causing the fluorophores to emit different wavelengths of light (e.g., longer wavelengths). These different wavelengths correspond to a different color than the absorbed light. The illumination light is separated from the weaker emitted fluorescence through the use of an emission filter. Multiple filters may be used to differentiate between the emissions of the fluorophores. The filtered emitted light for each fluorophore is converted into a digital image corresponding to a labeling pattern of the fluorophore within the specimen. The images acquired typically include intensity data, where the intensity of each pixel (e.g., on a scale of black to white) represents a level of fluorescence detected at that point in the specimen.
In multispectral fluorescence imaging, using W emission filters generates W corresponding images to output one image per fluorophore. Since the image acquisition is typically rapid, the W images may be registered to within a few pixels.
Labeled TOIs in multispectral fluorescence imaging data emit light at narrow, specific wavelengths that exclude emission from other components in the specimen. Many specimens (including samples of biological origin) frequently contain unpredictable material with which the fluorophores may bind, causing emission that passes through the specific filter, producing spurious intensity in the image. Additionally, some specimens exhibit inherent fluorescence that can be detected at the target emission wavelengths. Such situations could result in a false prediction of the presence of the TOIs. Additionally, several factors such as noise, occlusion, photobleaching, etc., can prevent a TOI from emitting a sufficient amount of light at the detected emission wavelength.
Therefore, a need exists for a system and method for distinguishing an emission indicating the presence of the TOIs from an emission that does not indicate the presence of the TOIs.
BRIEF SUMMARY
According to an embodiment of the present disclosure, an imaging system for detecting targets of interest (TOIs) in multispectral imaging data includes a memory device storing a plurality of instructions embodying the system for detecting TOIs, a processor for receiving the multispectral imaging data and executing the plurality of instructions to perform a method including determining a list of events collocated across images of the multispectral imaging data and labeling each event as one of a TOI or non-TOI.
According to an embodiment of the present disclosure, a method for detecting targets of interest (TOIs) in multispectral imaging data, the method includes determining a list of events collocated across images of the multispectral imaging data and labeling each event as one of a TOI or non-TOI.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be elucidated by reference to the embodiment partially illustrated schematically in the drawings regarding an exemplary medical application scenario using a favorable hardware set-up:
FIG. 1 is a diagram of a system for analyzing targets of interest in imaging data according to an embodiment of the present disclosure;
FIG. 2 is a flowchart of a method for detecting targets of interest in imaging data according to an embodiment of the present disclosure;
FIG. 3 is a flowchart of a method for event finding according to an embodiment of the present disclosure;
FIG. 4 is a flowchart of a method for classifying emission events according to an embodiment of the present disclosure;
FIG. 5 is a diagram of a computer system for identification of targets in multispectral imaging data according to an embodiment of the present disclosure.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
According to an embodiment of the present disclosure, a system and method are described for identifying, classifying and counting targets of interest (TOIs) in multispectral fluorescence imaging data. It should be noted that the material described herein can be applied to TOI detection/discrimination in any multichannel image, not just fluorescence imaging. The system and method may be conceptualized as including two parts: an event finder 101 for producing a list of events that are collocated across images and a classifier 102 for determining whether or not each event is a TOI (see FIG. 1 ).
Referring to FIG. 2 , according to an embodiment of the present disclosure, emission events are determined across images collected through the use of different emission filters (e.g., the same structure is labeled with different fluorophores) ( 201 ) and a classified ( 202 ) to determine whether or not these co-localized regions represent TOIs ( 203 ).
Embodiments of the system and method can distinguish emissions that indicate the presence of the TOIs from emissions that do not indicate the presence of the TOIs. Embodiments of the system and method include components for finding candidate events and classifying the events into true TOIs and false TOIs. Although traditional classification methods are widespread and effective, it is often difficult to adequately train a classifier since most images contain a mix of true/false events (which can be difficult to distinguish by the human eye) for which only an overall positive/negative label is assigned, e.g., obtained independently through a different diagnostic test.
According to an embodiment of the present disclosure, a method includes an event finder ( 201 ) and a classification routine ( 202 ).
Referring to FIGS. 1 and 2 and event finding ( 201 ); an event finder ( 101 ) receives input data, e.g., multispectral fluorescence imaging data including W images, and locates groups of high-intensity pixels that might represent a positive TOI. Event finding is applied separately to each of the W images, acquired with filters at different wavelengths. For purposes of notation, consider a set S of wavelengths (filters) for which images are acquired (i.e., |S|=W) that is indexed by the variable s.
Referring to FIG. 3 , to begin the event finding, a median filter with a small kernel (e.g., 3×3) is applied to a current image of the W images to remove stuck pixels, shot noise, etc. ( 301 ). Given this median filtered image, M s , belonging to frequency s, a mean filter with a kernel width exceeding twice the target TOI size (measured in pixels) is applied to produce the filtered image F s that tracks illumination changes (e.g., caused by distance from the illumination source) and overall background level ( 302 ). A response of the mean filter is subtracted to remove the illumination changes and background levels. A transform is applied to compensate for illumination and provide a rough measure of signal-to-noise (S/N) that reflects human brightness perception ( 303 ). The transformation may be written as:
T i 8 = log ( M i 8 F i 8 ) ( 1 )
in which the subscript i is used to indicate the value corresponding to pixel i. Note that a small constant (e.g., 1e-10 is added to the denominator to prevent division by zero).
The values of T s are now thresholded to produce a binary version of T s ( 304 ), which is denote as T B s by applying the threshold
Θ=mean( T 8 )+βvariance( T 8 ). (2)
Morphological operators of erosion and dilation are then applied to clean each T B 8 ( 305 ). Overlapping connected components of these binary masks across frequencies (i.e., for all T B 8 ) are then considered collocated if the following two conditions are met ( 306 ):
1. The overlap exceeds percent of the largest connected component. An exemplary value of v=0.25.
2. None of the connected components in a single channel (wavelength) overlap with more than one connected component in another channel.
The event finder ( 101 ) outputs a list of labels, which are shared across all wavelength images identifying corresponding connected components. The collection of pixels in each wavelength channel corresponding to the same label is considered to be one event.
Referring now to classification ( 202 ) and FIG. 4 , the event finder ( 201 ) located a set of events collocated across wavelength channels. Given this set of events, the classifier ( 102 ) determines if each event either indicates a TOI or represents noise. In order to make this determination, a training set of images is used. Due to the high number of events, manual classification of each event can be infeasible. However, given knowledge that certain sample specimens are “positive” (contain a TOI) or “negative” (do not contain a TOI), based on alternate diagnostic testing of the same specimen, training assumes that every event in a positive image represents a TOI while every event in a negative image does not represent a TOI. According to an embodiment of the present disclosure, given the training assumptions, a classification approach is described herein that tolerates label noise.
A feature vector is computed for each event by computing a series of measurements for an event across all wavelength images and concatenating these features into a single vector ( 401 ). Examples of features include brightness, blur and entropy. Assume that every training event is represented by a feature vector t and every test event is represented by vector v. A probability, x, is assigned to each vector that represents the probability that this event is a TOI ( 402 ). These probabilities can be assigned to the events in an image as follows:
1. Compute the inverse covariance matrix, C, of t.
2. Find the K-nearest neighbors (e.g., K=20) of each x and t, measured by the Mahalanobis distance (using C).
3. Treat the labels on t as boundary conditions (‘1’ if t i is from a positive specimen and ‘0’ if t i is from a negative specimen) and solve for a combinatorial harmonic function, described below, to assign probabilities to each v of being a TOI.
4. Depending on the confidence tolerance, assign t i to ‘positive’ or ‘negative’ if x i exceeds a threshold.
This procedure was applied to the training/testing of sample specimens infected with Respiratory Syncytial Virus (RSV), where one fluorophore was used to identify total cell count in a sample and another fluorophore was used to identify the presence of the virus. The results obtained were classification rates representing 80% sensitivity (i.e., true positive rate) and >99% specificity (i.e., the false positive rate) of RSV-infected cells. These classification rates mirror the ability of current, manual, methods of counting of cells using a fluorescence microscope.
Referring to the combinatorial harmonic function, given a set of feature vectors that have been specified as belonging to L image labels, remaining feature vectors can be labeled by a multi-label harmonic potential segmentation method. For an arbitrary L, and an image or volume of arbitrary dimensions, consider a person at every voxel starting to walk randomly across the volume until meeting a labeled feature vector, hereafter a label. The expected percentage of random walkers that first reach a label i are denoted as p i . If the walkers are biased to avoid crossing a sharp image gradient, such as an edge, to reach a neighboring voxel, the probability that a walker starting at a given pixel first strikes label i gives an indication of how strongly that feature vector belongs to label i. Once the set of {p 1 , p 2 , . . . , p 1 } is determined for each voxel, that voxel may be assigned to a particular label by choosing the label with the highest probability, the i corresponding to maxi(p i ).
It is to be understood that the present disclosure may be implemented in various forms of hardware, software, firmware, special purpose processors, or a combination thereof. In one embodiment, the present disclosure may be implemented in software as an application program tangibly embodied on a program storage device. The application program may be uploaded to, and executed by, a machine comprising any suitable architecture.
Referring to FIG. 5 , according to an embodiment of the present disclosure, a computer system 501 for identification of targets in multispectral imaging data the present disclosure can comprise, inter alia, a central processing unit (CPU) 502 , a memory 503 and an input/output (I/O) interface 504 . The computer system 501 is generally coupled through the I/O interface 504 to a display 505 and various input devices 506 such as a mouse and keyboard. The support circuits can include circuits such as cache, power supplies, clock circuits, and a communications bus. The memory 503 can include random access memory (RAM), read only memory (ROM), disk drive, tape drive, etc., or a combination thereof. The present disclosure can be implemented as a routine 507 that is stored in memory 503 and executed by the CPU 502 to process the signal from the signal source 508 , e.g., a multispectral fluorescence imaging device inputting imaging data. As such, the computer system 501 is a general purpose computer system that becomes a specific purpose computer system when executing the routine 507 of the present disclosure.
The computer platform 501 also includes an operating system and micro instruction code. The various processes and functions described herein may either be part of the micro instruction code or part of the application program (or a combination thereof) which is executed via the operating system. In addition, various other peripheral devices may be connected to the computer platform such as an additional data storage device and a printing device.
It is to be further understood that, because some of the constituent system components and method steps depicted in the accompanying figures may be implemented in software, the actual connections between the system components (or the process steps) may differ depending upon the manner in which the present disclosure is programmed. Given the teachings of the present disclosure provided herein, one of ordinary skill in the related art will be able to contemplate these and similar implementations or configurations of the present disclosure.
Having described embodiments for identification of targets in multispectral imaging data, it is noted that modifications and variations can be made by persons skilled in the art in light of the above teachings. It is therefore to be understood that changes may be made in embodiments of the present disclosure that are within the scope and spirit thereof. | An imaging system for detecting targets of interest (TOIs) in multispectral imaging data includes a memory device storing a plurality of instructions embodying the system for detecting TOIs, a processor for receiving the multispectral imaging data and executing the plurality of instructions to perform a method including determining a list of events collocated across images of the multispectral imaging data and labeling each event as one of a TOI or non-TOI. | 6 |
CROSS REFERENCE TO RELATED APPLICATION
This application claims the benefit of U.S. Provisional Patent Application No. 60/652,806, filed Feb. 14, 2005, and which is hereby incorporated by reference in its entirety.
TECHNICAL FIELD
This invention relates to vehicle wheel assemblies having a selectively retractable foot step.
BACKGROUND OF THE INVENTION
Situations frequently arise when a vehicle owner needs to access portions of a motor vehicle over the fender. For example, there may be a need to inspect or service the engine, a need to reach into the cargo bed, or a need to reach up to the overhead cargo racks. In this regard, larger automotive vehicles, such as for example, vans, sport utility vehicles and pick-up trucks, generally have high ground clearance and high uppermost height of the fenders. This height may result in inconvenience and/or difficulty for a person who is standing on the ground to access parts of the motor vehicle over the fenders. Some pick-ups have a step formed in the fenders on one side of the wheel well; some vehicles have running boards, and some vehicles have a step at the bumper. However, these provisions do not assist a person in accessing areas over the fenders directly above the wheel wells. Because of this, a person who needs to access parts of the motor vehicle over the fenders and above the wheel wells may need to utilize some object to stand upon, if one can be found.
SUMMARY OF THE INVENTION
A wheel assembly for a vehicle includes a rotatable wheel with a step assembly connected thereto. The step assembly includes a track member operatively connected to the wheel for rotation therewith and defining an annular track. A slide member is selectively movable along the annular track. A platform member defines a step surface and is pivotably mounted with respect to the slide member for movement between a deployed position in which the platform is horizontally oriented and a retracted position in which the platform is vertically oriented.
In the retracted positon, the platform member forms a center cap that obstructs the center portion of the wheel. In the deployed position the platform member presents a horizontal surface on which a person can step to elevate himself or herself. The step assembly provided may mount to the wheel in the same manner as a center cap.
The above features and advantages, and other features and advantages of the present invention are readily apparent from the following detailed description of the best modes for carrying out the invention when taken in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic, perspective view a vehicle wheel assembly including a step assembly with a step member in a retracted or stowed position;
FIG. 2 is a schematic, perspective view of the step assembly of FIG. 1 with the step member in a deployed position;
FIG. 3 is a schematic, perspective view of a track member of the step assembly of FIGS. 1 and 2 ;
FIG. 4 is a schematic, cross-sectional view of a portion of the track member and a slide member of the step assembly of FIGS. 1-3 ;
FIG. 5 is a schematic, perspective view of the slide member of FIG. 4 ;
FIG. 6 is a schematic, perspective view of the step member of FIGS. 1 and 2 ; and
FIG. 7 is a schematic, perspective view of an alternative track member in accordance with the claimed invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1 , a wheel 8 for a vehicle is schematically depicted. The wheel 8 includes a center cap that is also a step assembly 10 . Referring to FIG. 2 , the step assembly 10 includes an annular track member 14 that at least partially defines an annular track 18 . The track member 14 is connected to the wheel 8 for rotation therewith. The step assembly 10 further includes a slide member 22 movably mounted to the annular track 18 , and a plate 26 (also sometimes referred to herein as a “platform member”) that is pivotably connected to the slide member 22 . The plate 26 provides a step surface 28 on which a vehicle user can stand when it is in a generally horizontal position as shown in FIG. 2 . The plate 26 is pivotable to a retracted, generally vertically oriented position as shown in FIG. 1 .
A center emblem cap 29 is connected to the plate 26 opposite surface 28 . The center emblem cap 29 may depict a vehicle logo (not shown) or other identification, and is preferably selectively removable from the plate 26 to enable the step assembly 10 to be used on a variety of models. Thus, for example, the plate 26 , slide member 22 , and/or the track member 14 may be used on a variety of different vehicle models, each having a center emblem cap 29 with a different logo or other identification.
Referring to FIGS. 3 and 4 , wherein like reference numbers refer to like components from FIGS. 1 and 2 , the track member 14 defines a plurality of tabs 16 that engage slots (not shown) in the wheel to mount the track member to the wheel. The track member 14 partially defines track 18 , which is formed by a partially-annular inner surface 30 , two partially annular protrusions 34 , 38 , and two partially annular grooves 46 , 52 . Inner surface 30 is generally axially oriented with respect to the axis of rotation of the wheel to which the track member 14 is mounted and faces radially inward. Partially annular protrusions 34 , 38 protrude axially in opposite directions from one another and partially form surface 30 . Each protrusion 34 , 38 defines a respective surface 50 , 54 that at least partially forms one of grooves 46 , 52 .
Referring to FIGS. 4 and 5 , wherein like reference numbers refer to like components from FIGS. 1-4 , the slide member 22 defines a cavity 58 having a shape that approximates the curvature of the annular track 18 . The cavity 58 is formed by surfaces 60 , 64 , 68 , 70 , and 74 . The track 18 is at least partially within the cavity 58 such that surfaces 70 , 74 are positioned in a respective groove 46 , 52 ; surface 60 opposes surface 30 ; and surfaces 64 , 68 oppose surfaces 54 and 50 , respectively. Thus, physical part interference between the slide member 22 and the track member 14 restricts the movement of the slide member 22 with respect to the track member 14 to a circular path along the inner diameter of the track member 14 .
Referring again to FIG. 3 , the track member 14 defines an opening or notch 78 formed by the surface 30 and protrusions 34 , 38 to enable the installation of the slide member 22 on the track 18 . A member 84 having the same cross section as the track 18 is insertable into the notch 78 and affixable to the track member 14 after the slide member 22 has been affixed to the track member 14 to complete the annular track 18 .
Surface 30 of the track member 14 and the insert member 84 define a plurality of evenly-spaced, partially-spherical depressions or concavities 88 that function as detents. Referring to FIGS. 4 and 5 , roller elements 92 are rotatably attached to the slide member 22 and protrude from surface 60 , as shown in FIG. 5 . When the roller elements 92 enter respective concavities 88 , resistance to rotation of the slide member 22 with respect to the track member 14 is provided. The distance between each of the rollers 92 is the same as the distance between each of the concavities 88 .
Referring again to FIG. 6 , the slide member 22 includes a platform support portion 96 that defines holes 100 at which the plate 26 is pivotably connectable via a pin (not shown). More specifically, the pin extends through holes 100 and into holes (shown at 102 in FIG. 6 ) formed into the plate 26 . Those skilled in the art will recognize other techniques for pivotably connecting the plate 26 to the slide member 22 . Slide member 22 also includes a protrusion 104 that acts as a stop member by contacting the upper surface 28 of the plate 26 when the plate 26 is in the generally horizontal deployed position, as shown in FIG. 2 .
The platform support portion 96 of the slide member 22 includes a surface 106 characterized by plurality of evenly-spaced spaced protrusions 108 as shown in FIGS. 4 and 5 . The track member 14 also defines a surface 110 characterized by a plurality of evenly-spaced notches 112 on the outer face of the track member 14 , which is generally radially oriented to face the axial direction as shown in FIGS. 3 and 4 . Notches 112 are slightly larger than protrusions 108 . Under normal conditions, the protrusions 108 face notches 112 , but do not engage the notches. When a vehicle user steps on the plate 26 , the load exerted on the slide member 22 from the plate 26 causes sufficient deformation that the protrusions (as shown at 108 ′) enter respective notches 112 , preventing movement of the slide member 22 and plate 26 with respect to the track member 14 and the wheel.
Referring to FIG. 6 , the plate member 26 defines a notch 121 to accommodate the slide member when the plate member 26 is in its stowed position, as shown in FIG. 1 . The plate member 26 also defines detent depressions 122 in the notch 121 . Referring to FIGS. 5 and 6 , the slide member 22 defines semispherical protrusions 120 that are positioned to align with and engage detent depressions 122 to releasably retain the plate 26 in the retracted or stowed position. Plate member 26 also defines concavities 124 formed to remove mass from the plate to maintain even mass distribution around the step assembly 10 to avoid vibration when rotating about the wheel.
Referring to FIG. 7 , wherein like reference numbers refer to like components from FIGS. 1-6 , an alternative track member 14 ′ is schematically depicted. The track member 14 ′ includes an annular track portion 160 that defines the track 18 ′ and two wheel attachment portions 164 A, 164 B. Each wheel attachment portion 164 A, 164 B includes a radially inner portion 168 A, 168 B. Four legs 172 A-D extend radially outward from inner portion 168 A. Axially oriented segments 176 A-D interconnect respective legs 172 A-D with the track portion 160 . Similarly, four legs 178 A-D extend radially outward from inner portion 168 B. Axially oriented segments 180 A-D interconnect respective legs 178 A-D with the track portion 160 . Each axially oriented segment includes a flat, axially-oriented surface and a protuberance 182 A-D, 184 A-D extending radially outward therefrom. The protuberances engage a groove in the wheel to connect the track member 14 ′ to the wheel. The track member 14 ′ is sufficiently flexible such that the protuberances can be inserted into the groove. Inner portion 168 A defines surfaces 192 that oppose surfaces 188 formed by inner portion 168 B. A wedge (not shown) is inserted between surfaces 188 and surfaces 192 to prevent deformation of the track member 14 after the track member 14 is connected to the wheel and thereby retain protuberances 182 A-D, 184 A-D in the groove in wheel.
While the best modes for carrying out the invention have been described in detail, those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention within the scope of the appended claims. | A step assembly for an automotive wheel includes a first member at least partially defining an annular track, a second member connected with respect to the track for movement along the track, and a third member defining a stepping surface. The third member is pivotably connected with respect to the second member for selective movement between a stowed position in which the third member acts as a center wheel cap, and a second position in which the third member presents a horizontal step surface. The third member is movable along the track with the second member to enable a vehicle user to reposition the step surface after wheel rotation. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to cellular radio systems and in particular to handover techniques for use with communications networks including radio cells.
Handover is a technique that allows calls in a personal or mobile communication network to be maintained as a handset or mobile station moves between radio cells. After a call is set up, the quality of the radio link is monitored by the handset and by the associated cell base station. In addition, other channels from the same and adjacent cells are also monitored as potential links to handover to. According to pre-defined criteria the call is switched to another base-station as the mobile/handset moves, or the propagation conditions change, in order to maintain a good quality link. If this is not done, then the call quality may deteriorate seriously or the call may be "dropped" altogether. Either the network or the handset/mobile may incorporate the intelligence to enable the decisions to be made on when, whether and to which cell the radio link should be switched.
This type of handover is well known and widely adapted in conventional cellular systems. However, it gives rise to problems in mobile or personal communication networks where handsets or mobiles are moving at speed through areas covered by small cells such as sectored or microcells. Since the cells are small, the time spent in a cell is short and the time taken to initiate and perform handover may be too long. This leads to poor call quality and dropped calls.
SUMMARY OF THE INVENTION
According to one aspect of the present invention there is provided a cellular radio system including a plurality of cells each normally using a respective channel for control purposes, wherein a number of adjacent cells comprise a group of cells and in the event of a call associated with equipment moving in said group of cells the equipment is allocated a common channel for all cells of the group whereby to facilitate handover between the cells of the said group.
According to another aspect of the present invention there is provided a handover technique for use with a cellular radio system including a plurality of cells each normally using a respective channel for control purposes, a number of adjacent cells comprising a group of cells, and wherein in order to facilitate handover between the cells of a group in the event of a call associated with equipment moving in said group, a common channel is allocated to all cells of the group.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the invention will now be described with reference to the accompanying drawings, in which:
FIGS. 1a and 1b illustrate two examples of cell sectorisation;
FIG. 2 illustrates an array of sectored cells and handover within a group of sectored cells;
FIG. 3 illustrates an array of sectored cells and handover between one group of sectored cells and another; and
FIG. 4 illustrates an array of contiguous micro cells;
FIG. 5 illustrates a handover algorithm.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In some applications there are advantages, primarily of reduced interference, if a cell, typically 1 to 10 Km radius, is sectorised into a group of smaller cells by means of a directional antenna. FIGS. 1a and 1b show examples of 120 degree and 60 degree sectorisation. The multiple directional antenna 1 in each case normally serves to provide a respective control channel for each sector 2 of the cell. If the sectors are small, then handsets or mobile phones moving at speed can suffer poor call quality and dropped calls.
Conventionally, sectored cells use mutually exclusive channel sets to reduce interference, that is each sector of a cell has a respective channel of the set and each adjacent sectored cell has a different channel set. When a handset 3 (FIG. 2) moves from one cell sector 4 to another sector 5 of the same cell 6 (group of sectors) then a cell has to be handed over to a new channel supplied by the base station 7 in the adjacent sector 5, thereby leading to a requirement for very rapid handover.
This can be avoided in the following way. When movement of the handset 3 is detected, such as by bit error rates (BER) or low field strength, then a common "umbrella" channel is allocated to that handset in all the adjacent, nearby cell sectors i.e. the group of sectors 4, 5, 8, 9, 10, 11 making up the sectored cell 6 which itself covers a relatively large area. The base station antenna of the cell sectors of the group all transmit on the handset channel simultaneously in a synchronous or quasi-synchronous (simulcast) manner. This allows the handset to move between cell sectors within the group without handover explicitly taking place and without the handset having to switch channels since the operating channel for the handset in adjacent cell sectors is the same.
Although a single virtual channel is allocated to all cell sectors within a group, it is not essential for this channel to be the same physical channel. Thus the channels could be on different frequencies or time slots (in a TDMA frame). Since the channel frequency in each cell sector is pre-assigned and known a priori, handover to that cell sector can be performed more rapidly than with conventional handover. Under these or similar circumstances, it is not necessary for more than one base station to transmit at a time.
When the handset 3 moves outside of one cell 6 (group of cell sectors) (FIG. 3) to another 12, then handover is performed in the normal way to the new sector channel, or new "umbrella" channel if movement continues.
Another method of achieving continuous radio coverage is to use an array comprising a large number of overlapping microcells 13 (FIG. 4) which are typically 200 m in radius and have base stations 15. The main advantage of this is than the radiated power from the handset is low, as all radio paths are short, thus leading to longer battery life. However, as before, there are problems of performing handover very rapidly for handset moving at speed. This can be solved in a similar manner to that described above for sectored cells.
For reasons of interference reduction, adjacent microcells normally use different channels, as determined by a channel allocation scheme. However, when movement of a handset is detected (such as by marginal BER, low field strength or delay measurements), then a common "umbrella" channel is allocated to that handset in all of the microcells within a group of adjacent or nearby cells, that is a sub-array of the overall array. The hatched region of FIG. 4 illustrates such a sub-array i.e. a group 14 of nine microcells. The handover technique within and between groups is then exactly the same as for the sectored cells. The basic algorithm for handover is illustrated in FIG. 5, which is considered to be self-explanatory.
Alternatively, an area can be covered by macrocells each having an underlay of non-contiguous or overlapping microcells, each said macrocell and its associated microcells comprising a single two-layer cell. This "umbrella" approach covers movement of a mobile through a group of cells, however when stationary there can be fall back to the individual control channel in cell regime.
In summary, in the case of an area covered by sectored cells or overlapping microcells, calls from moving handsets are allocated a common channel across a number of cells forming a group of cells, allowing handover to take place very rapidly between cells of the group. When the handset moves between different groups of cells, handover takes place between the cells in the normal way. The common channel may be achieved by simultaneous transmission from many base stations or base station antennae within a group of cells, for overlapping microcells or sectored cells, respectively, which transmission can be in a synchronous or quasi-synchronous mode.
Attention is directed to our co-pending GB Application No. 9007809.8 (Serial No. GB A 2242806) (P.A. Ramsdale 5-4) corresponding to U.S. patent application Ser. No. 07/655634 filed Feb. 14, 1991, which relates to other handover techniques. | In a cellular radio system including a plurality of cells (e.g. cell sectors or micro cells) (4, 5, 8, 9, 10, 11) each normally using a respective channel for interference reduction purposes, a number of the cells are arranged in groups (6) and in the event of a cell associated with equipment moving within a group (6), all cells (4, 5, 8, 9, 10, 11) of that group use a common channel whereby to facilitate handover between them. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a content addressable memory or an associative memory comprising a number of word memories each for storing data, and having such a function that match or mismatch between data stored in word memories and retrieval data inputted to the word memories are retrieved.
2. Description of the Related Art
Recently, there has been proposed an associative memory provided with the retrieval function as mentioned above. First, there will be described arrangements and functions of the associative memory, and then examples of the field of application of the associative memory.
FIG. 9 is a circuit block diagram of the conventional associative memory by way of example.
Referring to FIG. 9, an associative memory 10 is provided with a number of word memories 11a, 11b, . . . , 11n each consisting of a 5-bit of serial memory cell by way of example. Further, the associative memory 10 comprises a retrieval register 12 which is arranged to receive and latch a word of retrieval data. A bit pattern of the retrieval data latched in the retrieval register 12 in its entirety or in a part specified is compared with a bit pattern of the portion corresponding to the bit pattern of the latched retrieval data with respect to data stored in each of the word memories 11a, 11b, . . . , 11n. As a result of the comparison, if there are found any of the word memories 11a, 11b, . . . , 11n of which the bit pattern matches with that of the retrieval data, a match signal given by a logic "1" will appear on the associated ones of match lines 14a, 14b, . . . , 14n which are provided in conjunction with the word memories 11a, 11b, . . . , 11n, respectively. On the other hand, a mismatch signal given by a logic "0" will appear on the remaining ones of the match lines 14a, 14b, . . . , 14n.
Assuming that the signals "0", "1", "0", "0", "1" . . . , "0" appear on the flag lines 14a, 14b, . . . , 14n, respectively, these signals are applied to a priority encoder 15. The priority encoder 15 is so arranged to output an address signal AD corresponding to the match line given with a highest priority among the match lines (here, two match lines 14b and 14e) on which the match signal given by a logic "1" appears. Supposing that the priority is higher as alphabet of a suffix of the reference character becomes younger, in this case, the match line 14b is selected as the highest priority match line. Thus, the priority encoder 15 outputs an address signal AD corresponding to the highest priority match line 14b, which address signal AD is applied to an address decoder 16, as occasion demands. The address decoder 16 decodes the received address signal AD and outputs an access signal (here a signal given by a logic "1") to the associated one (here a word line 17b) of word lines 17a, 17b, . . . , 17n which are provided in conjunction with the word memories 11a, 11b, . . . , 11n, respectively. Thus, data stored in the word memory 11b associated with the word line 17b on which the access signal appears is read out to an output data register 18.
As described above, according to the associative memory 10, the contents or data stored in a number of word memories 11a, 11b, . . . , 11n are retrieved using the retrieval data, so that an address of the word memory involved in the data match is generated, and thus it is possible to read out the whole data stored in the word memory.
FIG. 10 is a detailed circuit diagram of one of the word memories in the associative memory.
A word memory 11 comprises five memory cells 11-1, 11-2, . . . , and 11-n each having the same structure. The memory cells 11-1, 11-2, . . . , and 11-n are provided with first inverters 20-1, 20-2, . . . , and 20-n and second inverters 21-1, 21-2, . . . , and 21-n, in pairs such that their outputs are connected to their inputs, respectively. Providing pairs of inverters 20-1 and 21-1; 20-2 and 21-2; . . . ; and 20-n and 21-n permits the memory cells 11-1, 11-2, . . . , and 11-n to store one bit information expressed by logic "1" or logic "0", respectively.
In the memory cells 11-1, 11-2, . . . , and 11-n, the outputs of the first inverters 20-1, 20-2, . . . , and 20-n are connected through N channel transistors 22-1, 22-2, . . . , and 22-n to bit lines 23-1, 23-2, . . . , and 23-n, respectively. Gate electrodes of the transistors 22-1, 22-2, . . . , and 22-n are connected to a word line 24. The outputs of the second inverters 21-1, 21-2, . . . , and 21-n are connected through N channel transistors 25-1, 25-2, . . . , and 25-n to bit bar lines 26-1, 26-2, . . . , and 26-n, respectively. Gate electrodes of the transistors 25-1, 25-2, . . . , and 25-n are also connected to the word line 24. Further, in the memory cells 11-1, 11-2, . . . , and 11-n, there are provided pairs of N channel transistors 27-1 and 28-1; 27-2 and 28-2; . . . ; and 27-n and 28-n, respectively, which are connected in series between the bit lines 23-1, 23-2, . . . , and 23-n and the bit bar lines 26-1, 26-2, . . . , and 26-n, respectively. Gate electrodes of transistors 27-1, 27-2 . . . , and 27-n, as ones of these pairs of transistors 27-1 and 28-1; 27-2 and 28-2; . . . ; and 27-n and 28-n, are connected to the outputs of the first inverters 20-1, 20-2, . . . , and 20-n, respectively; and gate electrodes of other transistors 28-1, 28-2, . . . , and 28-n are connected to the outputs of the second inverters 21-1, 21-2, . . . , and 21-n, respectively.
On the match line 14, there are provided transistors 36-1, 36-2, . . . , and 36-n, which are associated with the word memories 11-1, 11-2, . . . , and 11-n, respectively, and are connected in series with each other. Gate electrodes of the transistors 36-1, 36-2, . . . , and 36-n are connected to points between pairs of transistors 27-1 and 28-1; 27-2 and 28-2; . . . ; and 27-n and 28-n, respectively.
Further, there is provided an additional transistor 36-0 connected in series with the match line 14 which is grounded through the transistor 36-0. A gate electrode of the transistor 36-0 is connected to the control line 30.
Furthermore, there is provided a sensing inverter 31 which is connected with the other end (right hand in FIG. 10) of the match line 14. The match line 14 extends also to the output side of the inverter 31 and is connected therethrough to the priority encoder 15 (refer to FIG. 9).
Between an input of the inverter 31 and the power supply V DD , there are provided two P-type of transistors 32 and 33. A gate electrode of the P-type of transistor 32 is connected to the control line 30. A gate electrode of the P-type of transistor 33 is connected to an output of the inverter 31.
In the associative memory having the word memories as mentioned above in structure and its peripheral circuits, a match retrieval is conducted in a manner as set forth below.
Assuming that the memory cell 11-1 stores information of a logic "1", the output side of the first inverter 20-1 takes a state of a logic "1", and the output side of the second inverter 21-1 takes a state of a logic "0".
It is assumed that a retrieval for a logic "1" is performed for the above-mentioned memory cell 11-1. That is, the bit line 23-1 is enabled with a logic "1", and the bit bar line 26-1 is enabled with a logic "0". While the word line 24 is kept in a state of a logic "0". Since a logic level "1" of voltage is applied to the gate electrode of the transistor 27-1, and a logic level "1" of signal on the bit line 23-1 is applied to the gate electrode of the transistor 36-1, the transistor 36-1 turns on. That is, when the bit information stored in the memory cell 11-1 and the bit information in the retrieval data entered through the bit line 23-1 and the bit bar line 26-1 are equivalent to each other, the associated transistor 36-1 turns on.
Assuming that the memory cell 11-2 stores information of a logic "0", the output side of the first inverter 20-2 takes a state of a logic "0", and the output side of the second inverter 21-2 takes a state of a logic "1".
It is assumed that a retrieval for a logic "1" is also performed for the above-mentioned memory cell 11-2. That is, the bit line 23-2 is enabled with a logic "1", and the bit bar line 26-2 is enabled with a logic "0". In this case, a logic level "0" of signal on the bit bar line 26-2 is applied through the transistor 28-2 to the gate electrode of the transistor 36-2, so that the transistor 36-2 is kept turning off. Thus, in case of the mismatch, the electric charge, which has been precharged on the match line 14, is not discharged.
With respect to the masked bit, as shown concerning the memory cell 11-n, both the bit line 23-n and the bit bar line 26-n are enabled with the logic "1". In this case, either the transistor 27-n or the transistor 28-n turns on in accordance with the fact that the memory cell 11-5 has stored logic "0" of information or logic "1" of information, so that the transistor 36-n turns on in any way.
To conduct a retrieval, first, the control line 30 is enabled with "0", so that a transistor 32 turns on whereby a match line 14 at the input side of the inverter 31 is precharged. Thereafter, the control line 30 is enabled with "1", so that the transistor 32 turns off to stop the precharge and the transistor 36-0 turns on.
In this case, when data stored in the memory cells 11-1, 11-2, . . . , and 11-n, which memory cells constitute the word memory 11, match with the entered retrieval information throughout the memory cells (as mentioned above, the masked bit is regarded as a "match"), all of the transistors 36-1, 36-2, . . . , and 36-n turn on, so that the electric charge, which has been precharged on the match line 14, is discharged. Thus, the inverter 31 outputs a logic "1" of signal.
Incidentally, it is noted that FIG. 10 merely shows by way of example the memory structure of the associative memory, and there are proposed various types of structure (See, for example, Japanese Patent Application No. 216424/1993).
Next, there will be described an example of application of the associative memory to a LAN (Local Area Network) hereinafter.
FIGS. 11(A)-11(C) are each a view showing an example of the LAN.
As shown in FIG. 11(A), it is assumed that coupled to two communication lines LAN 1 and LAN 2 are a plurality of terminals A-G, and T-Z, respectively to constitute two communication networks. Further, it is assumed that traffic volume of each of the communication lines LAN 1 and LAN 2, that is, quantity of data transmitted via the communication line, or a degree of congestion of the communication line, is given with "10".
When there occurs a necessity for connecting these two communication lines to each other, if they are simply connected to each other, as shown in FIG. 11(B), then the traffic volume of the communication lines LAN 1 and LAN 2 becomes 20. This involves such a result that the communication lines are dramatically congested, so that the connection among the terminals becomes more difficult, thereby increasing waiting time and idle time.
Hence, usually, as shown in FIG. 11(C), connected between the communication lines LAN 1 and LAN 2 is a bridge for performing filtering as to whether or not data originated from one of the communication lines LAN 1 and LAN 2 is transmitted to the other. When the bridge is connected, assuming that traffic volume of data passing through the bridge, that is, traffic volume as to transfer of data bridging two communication lines LAN 1 and LAN 2, is "1", adding traffic volume "10" of the interior of each of the communication lines LAN 1 and LAN 2, traffic volume of each of the communication lines LAN 1 and LAN 2 becomes "11". Thus, traffic volume is extremely decreased in comparison with the case, as shown in FIG. 11(B), in which two communication lines LAN 1 and LAN 2 are simply connected to each other. Here, while there has been described the connection between two communication lines LAN 1 and LAN 2, connection of a number of communication lines to the bridge may enhance the difference in the traffic.
FIG. 12 is an illustration useful for understanding the function of the bridge.
The bridge includes a memory. First, starting with a null state, for example, when data is transmitted from the terminal A of the communication line LAN 1, upon receipt of the data from the communication line LAN 1 end, the bridge learns that the terminal A is connected to the communication line LAN 1. This learning is conceptually implemented in such a manner that the memory inside of the bridge is provided with table 1 and table 2, which are associated with the communication lines LAN 1 and LAN 2, respectively, and the terminal A is written into the table 1 associated with the communication line LAN 1. At the time point of the learning of the terminal A, it is not determined whether or not the receiving destination of the data transmitted from the terminal A resides in the communication network involved in the LAN 1 end, and thus at this time point the data is allowed to pass through unconditionally the bridge.
Repeat of the above-mentioned learning makes it possible to build table 1 and table 2, as shown in FIG. 12, in the bridge. After these tables have been built, for example, as shown in the figure, data which is involved in terminal B (the LAN 1 end) as a transmitting source and terminal X (LAN 2end) as a receiving destination, is allowed to pass through the bridge, upon recognition by the bridge of the fact that the terminals B and X are located at opposite sides over the bridge each other. On the other hand, in a case where the transmitting source and the receiving destination are denoted by terminals A and E both belonging to the LAN 1 end, data is inhibited from passing through the bridge, upon recognition by the bridge of the fact that the terminals A and E reside in the communication network which is located at the same side looking from the bridge. This scheme contributes to reduction of traffic volume.
Adopting an associative memory as the memory used in the bridge as mentioned above may contribute to a high speed processing. For example, the associative memory is used to store information concerning the respective terminals A-G and T-Z, and further information as to whether each of those terminals belongs to table 1 (being connected to the LAN 1 end) or table 2 (being connected to the LAN 2 end). To determine whether or not data is allowed to pass through the bridge, for example, in a case where the receiving destination is given with terminal X, the retrieval is performed using "X" as retrieval data, and it is recognized that "X" is a terminal belonging to table 2 (LAN 2). In this manner, it may be determined whether or not data is allowed to pass through the bridge.
On the contrary, the bridge is equipped with the conventional RAM or the like, there are needs to read out one by one data stored and retrieve the data through sequential comparison to identify as to whether or not the read data is involved in the terminal X. Thus, in this case, a lot of time will be required for determination as to allowance of passage of data through the bridge or inhibition of the data.
As described above, the associative memory may be preferably used in, for example, a LAN network and the like. Whereas, for example, when data is transmitted from the terminal A, it is confirmed whether the terminal A is already registered in the memory of the bridge, and if not it is necessary to register the terminal A. In this manner, hitherto, there are needed two steps, one of which is involved in the confirmation of registration, and another the implementation of registration in case of not registered. This hinders higher speed operation of the bridge.
SUMMARY OF THE INVENTION
In view of the foregoing, it is therefore an object of the present invention to provide an associative memory capable of performing at high speed a registration of unregistered data.
The first associative memory according to the present invention, which attains the above-mentioned object, basically comprises at least one word memory for storing data, and at least one match detection circuit associated with said word memory for detecting a match or mismatch between a whole or a predetermined partial bit pattern of an entered retrieval data and a whole or a part of bit pattern corresponding to said bit pattern of the retrieval data among data stored in said word memory, characterized by:
a data additional writing circuit for providing such a control that when none of said match detection circuits outputs a match signal indicative of detection of a match, the retrieval data is stored in one of the word memories, which do not store effective data as a retrieval object and thus reside in an empty state permitting an overwriting, among said word memories.
In the above-mentioned first associative memory, said data additional writing circuit may comprise:
(1) at least one flag register associated with said word memory for storing a flag indicative of whether the associated word memory is one residing in a storage state such that said effective data is stored therein or another one residing in said empty state;
(2) a retrieval data writing circuit for selecting one word memory from among the word memories residing in said empty state to write said retrieval data in the selected word memory; and
(3) a flag alteration circuit for causing said flag register associated with said one word memory to store a flag indicative of said storage state, when none of said match detection circuits outputs the match signal.
Further, the second associative memory according to the present invention, which attains the above-mentioned object, basically comprises a plurality of word memory groups each comprising a plurality of word memories for storing a plurality of data constituting a single data group consisting of a plurality of storage data, wherein whenever retrieval data is entered, there is conducted a match retrieval between a whole or a predetermined partial bit pattern of an entered retrieval data and a whole or a part of bit pattern corresponding to said bit pattern of the retrieval data among data stored in said word memory, and in a predetermined number of times of match retrieval, including one time or a plurality of continuous number of times, the presence of the data group associated with the retrieval data entered said predetermined number of times is detected through detection of a match between a whole or a respective predetermined partial bit pattern of the entered retrieval data and a whole or a part of bit pattern corresponding to said bit pattern of the retrieval data among data stored in a same said word memory group throughout said predetermined number of times of match retrieval, characterized by:
a data writing circuit for writing the entered data, every retrieval during said predetermined number of times of match retrieval, in any one of the word memories within one word memory group selected from among the word memory groups which do not store effective data group as retrieval object and thus reside in an empty state permitting an overwriting.
In the above-mentioned second associative memory, it is preferable that said second associative memory further comprises:
(4) a plurality of flag registers each corresponding to an associated one of said plurality of word memory groups, for storing a flag indicative of whether the associated word memory group is one residing in a storage state such that said effective data group is stored therein or another one residing in said empty state; and
(5) a flag alteration circuit for causing said flag register associated with said one word memory group to store a flag indicative of said storage state, when there is not detected data group corresponding to the retrieval data entered the predetermined number of times, as a result of said predetermined number of times of match retrieval.
Further, as another aspect of the present invention, in the above-mentioned second associative memory, it is preferable that said second associative memory further comprises:
(6) a plurality of flag registers each corresponding to an associated one of said plurality of word memory groups, for storing a flag indicative of whether the associated word memory group is one residing in a storage state such that said effective data group is stored therein or another one residing in said empty state; and
(7) a flag alteration circuit responsive to a predetermined instruction signal entered from an exterior for causing said flag register associated with said one word memory group to store a flag indicative of said storage state.
According to the first associative memory of the present invention, upon receipt of information as to the fact that a match detection is not implemented through a retrieval, the retrieval data is stored at that time. Thus, there is no need to provide two steps, as in the related art, of a retrieval operation and a writing operation of data when a match detection is not implemented through a retrieval. Thus, it is possible to contribute to provide a higher speed of processing.
There is disclosed, in Japanese Patent Publication No. 31558/1986, a relevant art. Thus, a difference between the technology proposed in the relevant art and the present invention will be described hereinafter.
A number of word memories, which constitutes an associative memory, do not always data as an object of the retrieval in its entirety. It happens that a part of those word memories are each in an empty state in which effective data is not stored therein, or new effective data is written into the empty word memory. In this case, since it is troublesome to manage at the outside what word memory is in an empty state, a flag indicative of whether effective data is stored in the associated word memory, or the word memory concerned is in an empty state is stored in the associated word memory. When the effective data is written, the associative memory itself finds out the empty word memory to write the effective data therein.
The proposed technology in the relevant art is intended to avoid a necessity for management of word memories in the empty state at outside. However, the proposed technology needs two steps of a retrieval operation and a registration operation for data when unregistered.
On the contrary, according to the second associative memory of the present invention, there is provided a word memory group for storing data group, and a retrieval operation through entering retrieval data is performed a predetermined number of times so as to detect the presence of the associated data group.
Specifically, in such an associative memory, assuming that data group consisting of, for example, 100 pieces of data, is stored and a retrieval operation through entering retrieval data is performed repeatedly 100 times so as to detect the presence of a desired data group. According to the use of such a type of associative memory proposed hitherto that the presence of the data group is detected, if a desired data group is not found as a result of 100 times of retrieval, then a new effective data group will be registered through writing the retrieval data 100 times.
On the contrary, according to the second associative memory of the present invention, retrieval data is written into the word memory group residing in the empty state every retrieval. Thus, even if a desired data group is not found as a result of 100 times of retrieval, the retrieval data has been written every retrieval. Thus, this merely needs only a determination as to whether or not the word memory group, to which the new retrieval data have been written, is used for the subsequent retrieval and thereafter retrieval, whereby this permits the procedure of data writing to be remarkably reduced and contributes to the higher speed of processing.
The determination as to whether or not the word memory group, to which the new retrieval data have been written, is used for the subsequent retrieval and thereafter retrieval, may be implemented in such a manner that for example, the flag registers referenced to in the above items (4) or (6) are used to rewrite the flag stored in the flag register concerned.
Regarding the rewriting of the flag, it is preferable to provide such an arrangement in which the flag alteration circuit referenced to in the above item (5) is used, upon receipt of information indicating the fact that a desired data group is not detected through a predetermined number of times of retrieval, to automatically conduct the rewriting. Whereas, as another aspect of the present invention, it is also acceptable to provide such an arrangement in which the flag alteration circuit referenced to in the above item (7) is used to receive an instruction of rewriting from the exterior. In this case also, it is possible to contribute to the remarkable higher speed of processing.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a circuit diagram of an aspect portion of the first associative memory according to an embodiment of the present invention;
FIGS. 2(A) and 2(B) are each a circuit diagram of a plural-selection separating circuit by way of example;
FIG. 3 is an illustration of group structure of data by way of example;
FIG. 4 is a block diagram of an example of the associative memory adapted to deal with group structure of data;
FIG. 5 is a typical illustration showing a scheme of implementing a variable length of data line;
FIG. 6 is a typical illustration showing another scheme of implementing a variable length of data line;
FIG. 7 is a circuit diagram of an attribute determination circuit for determining as to whether or not an attribute is of "I";
FIG. 8 is a circuit diagram of an aspect portion of the second associative memory according to an embodiment of the present invention;
FIG. 9 is a circuit diagram of an associative memory according to the prior art by way of example;
FIG. 10 is a detailed circuit diagram of one of the word memories in the associative memory;
FIGS. 11(A)-11(C) are each an illustration of LAN's by way of example; and
FIG. 12 is a view useful for understanding a function of a bridge.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter, there will be described embodiments of the present invention.
FIG. 1 is a circuit diagram of an aspect portion of the first associative memory according to an embodiment of the present invention. In FIG. 1, the same parts are denoted by the same reference numbers as those of FIG. 10 involved in the related art.
In FIG. 1, arrangements of word memories 11 and match lines 14 are omitted. There are provided flag registers 51 each corresponding to the associated word memory 11. The flag register 51 stores a logical value "0" when the associated word memory 11 stores effective data which is the retrieval object, and stores a logical value "1" of empty flag when the associated word memory 11 stores ineffective data which is out of the retrieval object and thus allows overwrite (this is referred to as that the associated word memory 11 is "in an empty state"). Here, it is assumed that the flag registers 51 store, as shown in the figure, signals "0", "0", . . . , "1", respectively. A Q-output of the flag register 51 is applied to the associated plural-selection separating circuit 52. The plural-selection separating circuits 52 are connected in series, and are provided with the higher priority with upper one in the figure. In a case where the empty flag "1" is stored in a plurality of flag registers 51, the signal "1" is outputted from only the plural-selection separating circuit 52 associated with the flag register 51 having the highest priority among the plurality of flag registers 51 storing "1". Here, the flag register 51, which is placed at the lowest stage of the circuit diagram shown in FIG. 1, is provided with the highest priority. Thus, the signal "1" is outputted from the plural-selection separating circuit 52 placed at the lowest stage.
FIGS. 2(A) and 2(B) are each a circuit diagram of a plural-selection separating circuit 52 by way of example.
The plural-selection separating circuits 52 shown in FIG. 2(A) each comprise an AND gate 521 having two inputsone of which is inverted in input, and an OR gate 522, which are connected as shown in the figure. One of the inputs of the OR gate 522, illustrated in the top of the figure, constituting the plural-selection separating circuit 52, is earthed (ground GND).
In the plural-selection separating circuits 52, the priority is higher with upper one in the figure. In a case where the empty flag "1" is stored in a plurality of flag registers 51, the signal "1" is outputted from the AND gate 521 of the plural-selection separating circuit 52 associated with the flag register 51 having the highest priority among the plurality of flag registers 51.
The plural-selection separating circuits 52' shown in FIG. 2(B) each comprise, as shown in the figure, an inverter 523, an n-channel transistor 524, a p-channel transistor 526 and an exclusive OR gate 525. One end of the p-channel transistor 526, constituting each the plural-selection separating circuit 52', is connected to a power source V DD . And one of the inputs of the exclusive OR gate 525, illustrated in the top of the figure, constituting the plural-selection separating circuit 52', is earthed (ground GND).
Also in the plural-selection separating circuits 52' shown in FIG. 2(B), similar to the plural-selection separating circuits 52 shown in FIG. 2(A), the priority is higher with upper one in the figure. In a case where the empty flag "1" is stored in a plurality of flag registers 51, the signal "1" is outputted from the exclusive OR gate 525 of the plural-selection separating circuit 52' associated with the flag register 51 having the highest priority among the plurality of flag registers 51.
Connecting an encoder to the last stage of the plural-selection separating circuit shown in FIG. 2(A) or FIG. 2(B) may constitute the priority encoder 15 shown in FIG. 9.
Thus, in a case where the flag register 51 shown in the lowest part in FIG. 1 is the highest priority of one among the plurality of flag registers 51 which store the empty flag "1", the signal "1" is outputted from the associated plural-selection separating circuit 52, and then supplied to the AND gate 67. The input of the AND gate 67 is also connected to a word line activating timing signal line 68.
Assuming that when a retrieval is conducted through supplying retrieval data from a bit line drive circuit 70 to bit line 23-1, . . . , and 23-n, and bit bar line 26-1, . . . , and 26-n, respectively, the retrieval data and the data stored in the word memory shown in the top portion in the figure match, a match line 14 in the top is given with a logical value "1". Hence, an output of the AND gate 53 becomes a logical value "1", since an output of the associated flag register 51 is of a logical value "0". Here, a signal line extending from the output of the AND gate 53 is also referred to as a match line 140. All the match lines 140 corresponding to the associated word memories 11, respectively, are extended to an entirety match detection circuit 71, and also extended, instead of the match line 14 referred to in the relevant art, to the priority encoder 15 (FIG. 9). In a case where the flag register 51 stores the empty flag "1", even if there occurs a match on the word memory 11 associated with the flag register 51 concerned, the logical value "1" of signal on the match line 14 is inhibited by the AND gate 53. Thus, the match line 140 is kept "0". In other words, the word memory 11 concerned does not contribute to the retrieval.
The entirety match detection circuit 71 is arranged to perform an OR operation for the signals received through the match lines 140 to detect whether a match occurs on any word memory 11 or a mismatch occurs throughout the word memories 11. A result is supplied to an additional writing control circuit 72. The additional writing control circuit 72 provides such a control that while a retrieval is carried out through supplying retrieval data to the bit line 23-1, . . . , and 23-n, and the bit bar line 26-1, . . . , and 26-n, the word line activating timing signal line 68 is enabled with a signal "1" regardless of whether or not a match occurs on any word memory 11. As a result, an output of an AND gate 67 associated with the plural-selection separating circuit 52 located at the lowest stage in the figure becomes "1", and then a logical level "1" of signal appears on the associated word line 24. Thus, the retrieval data is written into the word memory 11 located at the lowest stage in the figure. The timing of the writing of the retrieval data is the same as the retrieval, and thus it is independently of whether or not a match occurs through the retrieval.
Thereafter, as described above, in the entirety match detection circuit 71, it is detected whether a match occurs on any word memory 11 or a mismatch occurs throughout the word memories 11, and a result is passed to the additional writing control circuit 72. In the additional writing control circuit 72, when a match occurs on any word memory 11, there is nothing to do thereafter. Specifically, while the retrieval data is overwritten onto the word memory 11 located at lowest stage, the associated flag register 51 stores still the empty flag "1". Consequently, the word memory 11 concerned is kept placed in the empty state such that it does not contribute to the retrieval.
On the other hand, in a case where it is detected by the entirety match detection circuit 71 that a mismatch occurs throughout the word memories 11, the additional writing control circuit 72 operates as follows.
While a logical value "0" of signal is applied to an empty flag data line 66 connected to the flag register 51, a clock pulse "1" is applied to an empty flag clock signal line 65. Since the word line 24 of the word memory 11 located at the lowest stage in the figure is given with a logical value "1" of signal, and this signal is passed via the signal line 60 to the AND gate 61 located at the lowest stage, the clock pulse applied to the empty flag clock signal line 65 is entered through the AND gate 61 concerned to the flag register 51 located at the lowest stage in the figure. Thus, the word memory 11 associated with the flag register 51 located at the lowest stage stores a logical value "0" indicating that an effective data as the retrieval object has been stored therein.
As the flag register 51 located at the lowest stage stores a logical value "0", the plural-selection separating circuit 52 may detect the highest priority of one from among the flag registers 51 storing the empty flag, except for the flag register 51 concerned.
Next, while an embodiment of the second associative memory of the present invention will be described, there is not yet well known an associative memory (see Japanese Patent Application No. 248121/1993) wherein data groups are beforehand stored for retrieval, to which a technical idea of the second memory of the present invention is preferably applicable. Consequently, first, there will be described associative memory itself as a base, and then the embodiment of the second associative memory of the present invention will be described.
FIG. 3 is an illustration of data having a group structure by way of example.
In FIG. 3, there is shown a data structure constituting a set of data group consisting of four pieces of data to which attributes I, II, III and IV are allotted, respectively. In order to make clear the conception of the data groups and the attributes, rising examples, data groups for the respective group numbers 1, 2, 3, 4 . . . , each denote data belonging to individual person, attribute I the person's name; attribute II the person's birth day; attribute III the person's address, . . . , and so on.
In case of the retrieval using an associative memory storing data groups each consisting of a plurality of data to which attributes I, II, III and IV are allotted, respectively, if the case such that data of, for example, the group number 1 is retrieved, by way of example, is explained, there is considered an associative memory capable of performing a various schemes of retrieval in view of requirements such that it is desired not only to perform retrieval of data "A" and "B" in the named order and read out the remaining data "C" and "D" other than the matched data group, but also to perform for example, retrieval of data "A" and "D" and read out the remaining data "B" and "C", or it is desired that first, the retrieval of data "B" is conducted, and then the retrieval of data "A" is conducted.
Here, as a matter of convenience of the later explanation, it is assumed that the group numbers n and n+1 is placed in the empty state in which no effective data group is recorded.
FIG. 4 is a block diagram of an example of the associative memory adapted to deal with group structure of data.
Match lines 14 -- 1, 14 -- 2, . . . , which are extended from the word memories 11 -- 1, 11 -- 2, . . . , respectively, are connected to ones of two input terminals of AND gates 20 -- 1, 20 -- 2, . . . , respectively. Connected to the other ones of the two input terminals of the AND gates 20 -- 1, 20 -- 2, . . . are output terminals of OR gates 21 -- 1, 21 -- 2, . . . , respectively. Ones of two input terminals of the OR gates 21 -- 1, 21 -- 2, . . . are connected to a first time retrieval control line 22.
Output terminals of the AND gates 20 -- 1, 20 -- 2, . . . are connected to data input terminals of first flag registers 23 -- 1, 2 -- 32, . . . , respectively. Output terminals of the first flag registers 23 -- 1, 23 -- 2, . . . are connected to input terminals of second flag registers 24 -- 1, 24 -- 2, . . . , respectively. Output terminals of the second flag registers 24 -- 1, 24 -- 2, . . . are connected to the priority encoder 15 shown in FIG. 9 (omitted in FIG. 4), and in addition through the first switch 33 -- 1, 33 -- 2, . . . , to data lines 32 -- 1, 32 -- 2, . . . , respectively, which data lines 32 -- 1, 32 -- 2, . . . , are provided for the associated word memory groups each for storing data group, respectively.
Applied to both the first flag registers 23 -- 1, 23 -- 2, . . . and the second flag registers 24 -- 1, 24 -- 2, . . . are a match result latch signal S1 which appears on a match result latch control line 25, so that input data entered from the respective data input terminals are latched. In the first flag registers 23 -- 1, 23 -- 2, . . . , there are latched the input data involved in the time point of a rising edge a of the match result latch signal S1. On the other hand, in the second flag registers 24 -- 1, 24 -- 2, . . . , there are latched the input data involved in the time point of a falling edge b of the match result latch signal S1.
Word memories 11 -- 1, 11 -- 2, . . . comprise attribute storage units 11 -- 1 -- 1, 11 -- 2 -- 1, . . . each for storing an attribute and data storage units 11 -- 1 -- 2, 11 -- 2 -- 2, . . . each for storing data, respectively. The word memories 11 -- 1, 11 -- 2, . . . each store storage data consisting of a pair of mutually associated attribute and data. As shown in FIG. 4, it is assumed that the word memories 11 -- 1, 11 -- 2, 11 -- 3 and 11 -- 4 store attribute I and data `A`, attribute II and data `B`, attribute III and data `C` and attribute IV and data `D`, respectively, which belong to group No.1 shown in FIG. 3. Similarly, the word memories 11 -- 5, 11 -- 6, . . . store attribute I and data `C`, attribute II and data `F`, . . . , respectively, which belong to group No.2 shown in FIG. 3. To effect the retrieval, reference data REF -- DATA, which consists of a pair of attribute and data, is applied.
The word memories 11 -- 1, 11 -- 2, . . . are provided with attribute match lines 30 -- 1, 30 -- 2, . . . , to which each signal representative of a match or mismatch concerning only the attribute is supplied, as well as the conventional match lines 14 -- 1, 14 -- 2, . . . , respectively, to which each a match signal is supplied when the storage data (both the attribute and the data) coincides with the applied reference data (both the attribute and the data). With respect to detection of a match of only the attribute and a match of both the attribute and the data, it is possible to implement such a function with the use of the conventional match detection circuit. Thus, the illustration of such a match detection circuit and the explanation will be omitted.
There are provided third flag registers 31 -- 1, 31 -- 2, . . . , which are associated with the word memories 11 -- 1, 11 -- 2, . . . , respectively. The attribute match lines 30 -- 1, 30 -- 2, . . . are extended to data input terminals of the associated third flag registers 31 -- 1, 31 -- 2, . . . , respectively. Further, in the associative memory according to the present embodiment, there are provided data lines 32 -- 1, 32 -- 2, . . . each on the associated word memory group comprising word memories each storing data belonging to the associated data group shown in FIG. 3, as mentioned above. Furthermore, there are provided first switches 33 -- 1, 33 -- 2, . . . between the data lines 32 -- 1, 32 -- 2, . . . and output terminals of the third flag registers 31 -- 1, 31 -- 2, . . . , respectively. The first switches 33 -- 1, 33 -- 2, . . . are each constituted of a transistor and the like. Also with respect to other switches described later, it is the same as this constitution. The first switches 33 -- 1, 33 -- 2, . . . turn on when the associated third flag registers 31 -- 1, 31 -- 2, . . . each latch a logic "1" of signal, respectively, and they turn off when latching a logic "0" of signal. The third flag registers 31 -- 1, 31 -- 2, . . . latch signals appearing on the associated attribute match lines 30 -- 1, 30 -- 2, . . . , respectively, in timing of the trailing edge b of the match result latch signal S1 which appears on the match result latch control line 25.
Furthermore, there are provided second switches 34 -- 1, 34 -- 2, . . . between the data lines 32 -- 1, 32 -- 2, . . . and input terminals of OR gates 21 -- 1, 21 -- 2, . . . , respectively. The second switches 34 -- 1, 34 -- 2, . . . are controlled in such a manner that they turn on when signals of the associated attribute match lines 30 -- 1, 30 -- 2, . . . each take a logic level "1" representative of a match, and they turn off when taking a logic "0" representative of a mismatch.
In the associative memory arranged as described above, a match retrieval is effected in such a manner as set forth below.
To retrieve solely individual retrieval data, a first time retrieval timing signal S2 is supplied to the first time retrieval control line 22, when the retrieval is performed through inputting the reference data REF-DATA. Assuming that attribute II and data "B" are inputted as the reference data REF-DATA, a logic "1" of match signal appears on the match line 14 -- 2 associated with the word memory 11 -- 2 in which attribute II and data "B" has been stored, and is supplied to the AND gate 20-2. Simultaneously, the first time retrieval timing signal S2 is supplied via the first time retrieval control line 22 through the OR gate 21 -- 2 to the AND gate 20 -- 2. As a result, the AND gate 20 -- 2 produces a logic "1" of signal. On the other hand, since logic "0" of signals appear on the other match lines 14 -- 1, 14 -- 3, 14 -- 4, . . . , respectively, the associated AND gates 20-1, 20 -- 3, 20 -- 4, . . . produce logic "0" of signals, respectively.
The logic "1" of signal outputted from the AND gate 20 -- 2 is latched by the first flag register 23 -- 2 in timing of the rising edge a of the match result latch signal S1 appearing on the match result latch control line 25, and then latched by the second flag register 24 -- 2 in timing of the subsequent falling edge b of the match result latch signal S1.
On the other hand, logic "0" of signals are latched by the other first flag registers 23 -- 1, 23 -- 3, 23 -- 4, . . . in the same timing as the logic "1" of signal is latched by the first flag register 23 -- 2, and logic "0" of signals are latched by the other second flag registers 24 -- 1, 24 -- 3, 24 -- 4, . . . in the same timing as the logic "1" of signal is latched by the second flag register 24 -- 2.
In this manner, signals expressed by logic "0", "1", "0", . . . , which are latched by the second flag registers 24 -- 1, 24 -- 2, 24 -- 3, . . . , respectively, are supplied to the priority encoder 15 as shown in FIG. 9 to generate an address signal AD of the word memory 11 -- 2.
Next, there will be described a case of a plurality of number of times of continuous data retrieval. In this case, the first time of retrieval is the same as the operation of a single data retrieval as mentioned above. In the retrieval for the first time, however, there is additionally performed the following operation for preparation of the second time of data retrieval.
In the data retrieval for the first time, upon receipt of a match of the attribute, a logic "1" of signal appears on the attribute match line 30 -- 2 associated with the word memory 11 -- 2. As a result, a logic "1" of signal is latched also by the associated third flag register 31 -- 2, so that the associated first switch 33 -- 2 turns on, whereby a logic "1" of signal stored in the associated second flag register 24 -- 2, which logic "1" is representative of a match of both the attribute and the data, is supplied to the data line 32 -- 1. Simultaneously, the associated second switch 34 -- 2 also turns on. However, this is useless operation for the first retrieval.
Next, let us consider a retrieval through inputting a reference data REF -- DATA consisting of attribute IV and data "D". In this case, the first time retrieval control line 22 is kept at a logic level "0". In this state, upon receipt of a match of the attribute, a logic "1" of signal appears on the attribute match line 30 -- 4 associated with theword memory 11 -- 4. As a result, the associated second switch 34 -- 2 turns on, so that the logic "1" of signal, appearing on the data line 32 -- 1, of the associated second flag register 24 -- 2 is applied through an OR gate 21 -- 4 to an AND gate 20 -- 4. Hence, when a match of both the attribute IV and the data "D" is detected in the word memory 11 -- 4 and a logic "1" of match signal is supplied to a match line 14 -- 4, a logic "1" of signal is latched, by the associated first and second flag registers 23 -- 4 and 24 -- 4 in compliance with the match result latch signal S1 which appears on the match result latch control line 25, in rising and falling edges of the latch signal S1, respectively. Whereas a logic "1" of signal supplied to the attribute match line 30 -- 4 is latched in the trailing edge of the latch signal S1 by the associated third flag register 31 -- 4, so that the associated first switch 33 -- 4 turns on whereby the logic "1" of signal is supplied to the data line 32 -- 1. In the second time of retrieval, a logic "0" of signal representative of a mismatch of attribute is supplied to the attribute match line 30 -- 2 associated with the word memory 11 -- 2, and thus the associated third flag register 31 -- 2 stores a logic "0" of signal, whereby the first switch 33 -- 2 associated with the word memory with the word memory 11 -- 2 turns off in timing of trailing edge of the latch signal S1.
With respect to encoding of the bit address, a logic "1" of signal of the second flag register 24 -- 4 associated with the word memory 11 -- 4 is applied to the priority encoder 15 (see FIG. 9) so that the address of the word memory 11 -- 4 is derived. Here, it is known beforehand that attribute IV has been stored in the word memory 11 -- 4. Accordingly, when it is desired that data involved in, for example, the attribute III within the same group is read out, it may be sufficient that the address of the word memory 11 -- 3 is determined through subtracting 1 from the derived address, and the determined address is applied to the address decoder 16 to read the content of the word memory 11 -- 3.
In the second time of retrieval, if the retrieval is carried out with the use of the reference data consisting, for example, attribute IV and data "B", instead of the reference data consisting attribute IV and data "D", regarding the word memory 11 -- 4, the associated second switch 34 -- 4 turns on since a match of the attribute is attained, so that a logic"l" of signal appearing on the data line 32 -- 1 is taken in. Whereas, since the data is different, a logic "0" of signal representative of a mismatch is supplied to the match line 14 -- 4, so that the first and second flag registers 23 -- 4 and 24 -- 4 latch a logic "0" indicating that no match is detected. Further, regarding the word memory 11 -- 2 involved in a match of data "B", it involves no match of the attribute and thus involving no match of both the attribute and the data.
In such a manner as mentioned above, according to the embodiment shown in FIG. 4, it is possible to implement a retrieval even in a case where data to be retrieved are stored in mutually distant word memories as far as those within the same group, or a case where the retrieval is effected independently of a sequence of data stored in the word memories.
According the embodiment as described above, the data line 32 -- 1, 32 -- 2, . . . , are each fixed in length on the assumption that the number of data belonging to a single group is predetermined. However, providing such a fixed length of data line causes such a necessity that a maximum of the number of data belonging to a single group is estimated to provide a data line having a length corresponding to the maximum data number. This causes useless word memories when data groups each are constituted of data less than the maximum. Thus, it is preferable to adopt a variable length of data line to meet the number of data belonging to a single group.
FIG. 5 is a typical illustration showing a scheme of implementing a variable length of data line.
Data line 32 is extended over a plurality of word memories 11 -- 1, 11 -- 2, 11 -- 3, . . . . On the data line 32 there are arranged in series switches 40 -- 2, 40 -- 3, 40 -- 4, . . . , which are associated with the word memories 11 -- 2, 11 -- 3, . . . , respectively, except the uppermost stage of word memory 11 -- 1. The switches 40 -- 2, 40 -- 3, 40 -- 4, . . . are disposed between the associated word memories 11 -- 2, 11 -- 3, 11 -- 4, . . . and the immediately upwards adjacent word memories 11 -- 1, 11 -- 2, 11 -- 3, . . . , respectively. Among the switches 40 -- 2, 40 -- 3, 40 -- 4, . . . , the switches 40 -- 2, 40 -- 4, 40 -- 6, . . . disposed every other switch turn on in accordance with the first switch control signal on the first control line 41; the switches 40 -- 3, 40 -- 7, . . . disposed every fourth switch, the second switch control signal on the second control line 42; and the switches 40 -- 5, . . . disposed every eighth switch among the remaining switches, the third switch control signal on the third control line 43.
In a case where the number of data constituting a data group is given with 2, supplying the first switch control signal to the first control line 41 causes the switches 40 -- 2, 40 -- 4, 40 -- 6, . . . disposed every other switch to turn on. Thus, there is formed the data line which is broken in every two word memories 11 -- 1, 11 -- 2; 11 -- 3, 11 -- 4; 11 -- 5, 11 -- 6; . . . . In a case where the number of data constituting a data group is given with 4, the first switch control signal is supplied to the first control line 41, and in addition the second switch control signal is supplied to the second controlline 42. As a result, there is formed the data line which is broken in every four word memories 11 -- 1, 11 -- 2, 11 -- 3, 11 -- 4; 11 -- 5, 11 -- 6, . . . . Likewise, in a case where the number of data constituting a data group is given with 8, the first switch control signal and the second switch control signal are supplied to the first control line 41 and the second control line 42, respectively, and in addition the third switch control signal is supplied to the third control line 43. As a result, there is formed the data line which is broken in every eight word memories 11 -- 1, . . . , 11 -- 8; 11 -- 9, . . . .
According to the above-described scheme, in a case where the number of data constituting a data group is given with 2N where N=integer, there occurs no idle in the word memory. However, in case of other than 2N, for example, 3, 5, 9, etc., there would occur idle word memories. The constitution, which permits a number of switches switches 40 -- 2, 40 -- 3, . . . to optionally turn on and off, needs a lot of control lines, and also makes a control circuit for supplying the switch control signals to those control lines complicated. Consequently, the scheme shown in FIG. 5 is inadequate to control optionally a length of the data line.
FIG. 6 is a typical illustration showing another scheme of implementing a variable length of data line.
It is the same as the case in FIG. 5 that data line 32 is extended over a plurality of word memories, and on the data line 32 there are arranged in series switches 40 -- 2, 40 -- 3, 40 -- 4, . . . , which are associated with the word memories, respectively, except the uppermost stage of word memory.
The word memories are provided with attribute storage units 11 -- 1 -- 1, 11 -- 2 -- 1, 11 -- 3 -- 1, . . . , respectively. In the attribute storage units 11 -- 1 -- 1, 11 -- 2 -- 1, 11 -- 3 -- 1, . . . , there are stored attributes I, II, III and IV as shown in the figure, respectively. According to this example, it is so arranged that the switches are controlled in their turn-on or off depending on the attributes I or other than I, that is, II, III and IV which are stored in the attribute storage units 11 -- 1 -- 1, 11 -- 2 -- 1, 11 -- 3 -- 1, . . . , in such a manner that in case of the attribute I the associated switch is kept off, and in case of the attributes II, III or IV the associated switch is turned on. Such an arrangement makes it possible to form the data line which is broken in every word memories automatically given with an adequate number, independently of the number of data constituting a data group, through disposing attribute I of data at the initial of each data group, even if there are mixed data groups each consisting of a different number of data.
FIG. 7 is a circuit diagram of an attribute determination circuit for determining as to whether or not an attribute is of "0".
Here, it is assumed that "000" is assigned to the attribute I. When an attribute stored in an attribute storage unit 11 -- i -- 1 is the attribute I ("000"), an OR gate 41 produces a logic "0" signal. Thus, a switch 40' comprising a transistor turns off, so that the data line of the switch 40' is electrically broken in its both sides. When an attribute stored in the attribute storage unit 11 -- i -- 1 is other than the attribute I, the OR gate 41 produces a logic "1" signal. Thus, the switch 40' turns on, so that the data line of the switch 40' is electrically coupled between its both sides.
In this manner, in the associative memory shown in FIG. 4, it is also to adjust a length of each of the data lines 32 -- 1, 32 -- 2, . . . in accordance with the number of data constituting a data group. It is acceptable to vary or adjust a length of the data line through controlling the switch with the use of control lines for exclusive use or providing additional attribute bits.
Next, there will be described an embodiment of the second associative memory of the present invention in which a technical idea of the present invention is applied to the associative memory shown in FIG. 4 and described above.
FIG. 8 is a circuit diagram of an aspect portion of the second associative memory according to an embodiment of the present invention. In FIG. 8, the same parts are denoted by the same reference numbers as those of FIG. 1, and the redundant description will be omitted.
FIG. 8 shows a word memory group for storing data group related to the group No. n from among a plurality of data groups shown in FIG. 3, that is, the highest priority of one of the word memory groups which reside in the empty state.
The associative memory shown in FIG. 8 is, similar to that shown in FIG. 1, provided with flag registers . . . , 51 -- 1 -- n, 51 -- 2 -- n, . . . , 51 -- 1 -- n+1, . . . , associated with the word memories . . . , 11 -- 1 -- n, 11 -- 2 -- n, . . . , 11 -- 1 -- n+1, . . . , respectively. The flag registers . . . , 51 -- 1 -- n, 51 -- 2 -- n, . . . , 51 -- 1 -- n+1, . . . , are controlled on a batch basis in units of word memory groups in such a manner as will be described later. In those flag registers, the top of the flag registers on each word memory group is effective.
The word memories . . . , 11 -- 1 -- n, 11 -- 2 -- n, . . . , 11 -- 1 -- n+1, . . . , consist of attribute storage units . . . , 11 -- 1 -- 1 -- n, 11 -- 2 -- 1 -- n, . . . , 11 -- 1 -- 1 -- n+1, . . . , for storing attributes and data storage units . . . , 11 -- 1 -- 2 -- n, 11 -- 2 -- 2 -- n, . . . , 11 -- 1 -- 2 -- n+1, . . . , for storing data, respectively. Incidentally, in FIG. 8, as a matter of convenience, the attribute storage units . . . , 11 -- 1 -- 1 -- n, 11 -- 2 -- 1 -- n, . . . , 11 -- 1 -- 1 -- n+1, . . . , and data storage units . . . , 11 -- 1 -- 2 -- n, 11 -- 2 -- 2 -- n, . . . , 11 -- 1 -- 2 -- n+1, . . . , are depicted at the mutually different places.
It is assumed that the respective word memories associated with the group numbers n and n+1 reside in the empty state, and thus flag registers 51 -- 1 -- 1 -- n, 51 -- 2 -- 1 -- n, . . . , 51 -- 1 -- 1 -- n+1, . . . , each store a logical value "1" of flag indicative of the empty state.
First transistors . . . , 81 -- 1 -- n, 81 -- 2 -- n, . . . , 81 -- 1 -- n+1, . . . , are controlled in their turn on/turn off through the associated control wires extending from the attribute storage units . . . , 11 -- 1 -- 1 -- n, 11 -- 2 -- 1 -- n, . . . , 11 -- 1 -- 1 -- n+1, . . . , respectively. Those first transistors turn on only when the attribute storage units . . . , 11 -- 1 -- 1 -- n, 11 -- 2 -- 1 -- n, . . . 11 -- 1 -- 1 -- n+1, . . . , store attribute I. Consequently, outputted to the firstvariable length data line 83 -- n associated with the group number n is a logical level "1" ("H" level) of signal indicative of the empty state, which is stored in the flag register 51 -- 1 -- n. This signal is applied to four plural-selection separating circuits 52 -- 1 -- n, 52 -- 2 -- n, 52 -- 3 -- n and 52 -- 4 -- n in the word memory group associated with the group number n. Further, the signal appearing on the first variable length data line 83 -- n is applied through inversion in logic to four AND gates 53 -- 1 -- n, 53 -- 2 -- n, 53 -- 3 -- n and 53 -- 4 -- n in the word memory group associated with the group number n.
This is the similar as to the matter of the word memory group associated with the group No. n+1. A logical level "1" of signal, which is stored in the flag register 51 -- 1 -- n+1, is applied via the first variable length data line 83 -- n+1 to four plural-selection separation circuits 52 -- 1 -- n+1, . . . , and upon inversion in logic to four AND gates 53 -- 1 -- n+1, . . . .
As shown in FIG. 3, when an effective data group has been stored in the word memory group associated with the group No. 1, 2, . . . , n-1, a logical value "1" ( "H" level) of signal indicative of the highest priority is outputted from the uppermost stage of plural-selection separating circuit 52 -- 1 -- n among four plural-selection separating circuits 52 -- 1 -- n, 52 -- 2 -- n, 52 -- 3 -- n and 52 -- 4 -- n. Outputs of the plural-selection separating circuits . . . , 52 -- 1 -- n, 52 -- 2 -- n, . . . , 52 -- 1 -- n+1, . . . , are connected to the second transistors . . . , 82 -- 1 -- n, 82 -- 2 -- n, . . . , 82 -- 1 -- n+1, . . . , respectively. Those second transistors turn on, similar to the first transistors . . . , 81 -- 1 -- n, 81 -- 2 -- n, . . . , 81 -- 1 -- n+1, . . . , only when the attribute storage units . . . , 11 -- 1 -- 1 -- n, 11 -- 2 -- 1 -- n, . . . 11 -- 1 -- 1 -- n+1, . . . , store attribute I. A logical value "1" of signal outputted from the plural-selection separating circuit 52 -- 1 -- n is passed through the second transistors 82 -- 1 -- n to the second variable length data line 84 -- n. Here, the highest priority of word memory group is assigned to the group number n. Consequently, the output of the plural-selection separating circuit 52 -- 1 -- n+1 involved in the word memory group associated with the group number n+1 is of a logical value "0", so that the logical value "0 " of signal, which is the output of the plural-selection separating circuit 52 -- 1 -- n+1, is supplied to the second variable length data line 84 -- n+1 associated with the group number n+1.
The attribute storage units . . . , 11 -- 1 -- 1 -- n, 11 -- 2 -- 1 -- n, . . . , 11 -- 1 -- 1 -- n+1, . . . , are coupled via attribute match lines . . . , 30 -- 1 -- n, 30 -- 2 -- n, . . . , 30 -- 1 -- n+1, . . . , to input terminals of the AND gates . . . , 53 -- 1 -- n, 53 -- 2 -- n, . . . , 53 -- 1 -- n+1, . . . , respectively. The attribute match lines . . . , 30 -- 1 -- n, 30 -- 2 -- n, . . . , 30 -- 1 -- n+1, . . . , are enabled, upon receipt of a match of the attribute in the retrieval, with a logical value "1" ("H" level) of signal. The data storage units . . . , 11 -- 1 -- 2 -- n, 11 -- 2 -- 2 -- n, . . . , 11 -- 2 -- 1 -- n+1, . . . , are coupled via data match lines . . . , 14 -- 1 -- n, 14 -- 2 -- n, . . . , 14 -- 1 -- n+1, . . . , to input terminals of the AND gates . . . , 53 -- 1 -- n, 53 -- 2 -- n, . . . , 53 -- 1 -- n+1, . . . , respectively. The data match lines . . . , 14 -- 1 -- n, 14 -- 2 -- n, . . . , 14 -- 1 -- n+1, . . . , are enabled, upon receipt of a match of the data in the retrieval, with a logical value "1" ("H" level) of signal, in a similar fashion to that of the attribute match lines . . . , 30 -- 1 -- n, 30 -- 2 -- n, . . . , 30 -- 1 -- n+1, . . . ,.
Assuming that when data retrieval is conducted through inputting attribute II and data "B", data "B" has been stored in the data storage unit 11 -- 2 -- 2 -- n of the word memory 11 -- 2 -- n wherein the attribute storage unit 11 -- 2 -- 1 -- n stores attribute II, accidentally. Then, upon receipt of a match of the attribute, the attribute match line 30 -- 2 -- n is enabled with a "H" level. And upon receipt of a match of the data, the data match line 14 -- 2 -- n is also enabled with a "H" level. However, since the first variable length data line 83 -- n resides in a "H" level indicative of the empty state, a "H" level of signal indicative of the match is not derived from the AND gate 53 -- 2 -- n. In other words, the word memories residing in the empty state do not attend to the retrieval.
While the retrieval is conducted, regardless of whether or not the match is detected in any word memory groups, a logical value "1" of signal is outputted from the additional writing control circuit 72 (see FIG. 1) to the word line activating timing signal line 68. As a result, all the inputs of the AND gate 67 -- 2 -- n associated with the word memory 11 -- 2 -- n, which is the second one from the top in FIG. 8, become "1", and a logical value "1" of signal appears on the word line 24 -- 2 -- n extending to the output end of the AND gate 67 -- 2 -- n. Thus, the retrieval data is written into the word memory 11 -- 2 -- n. The timing of writing of the retrieval data is the same as the retrieval, and thus it is independently of whether or not the match occurs in the retrieval.
After the above-mentioned retrieval and writing of the retrieval data are carried out a predetermined number of times, the additional writing control circuit 72 (see FIG. 1) receives information as to whether or not a desired data group is finally detected. In the additional writing control circuit 72, when a desired data group is detected in any word memory group, there is nothing to do thereafter. Specifically, while the retrieval data is written into the word memory group associated with the group number n shown in FIG. 8, whenever the retrieval is conducted, the flag registers 51 -- 1 -- n, 51 -- 2 -- n, 51 -- 3 -- n and 51 -- 4 -- n associated word memory concerned stores still the empty flag "1". Consequently, the word memory group associated with group number n is kept placed in the empty state such that it does not contribute to the retrieval.
On the other hand, when the entirety match detection circuit 71 does not detect any desired data group throughout the word memory groups, the additional writing control circuit 72 operates as follows.
While a logical value "0" of signal is applied to an empty flag data line 66 connected to the flag registers . . . , 51 -- 1 -- 1 -- n, 51 -- 2 -- 1 -- n, . . . , 51 -- 1 -- 1 -- n+1, . . . , a clock pulse "1" is applied to an empty flag clock signal line 65. Since a logical value "1" of signal is applied to the second variable length data line 84 -- n extending to the word memory group associated with the group number n shown in the figure, the clock pulse "1" applied to the empty flag clock signal line 65 is entered through four AND gates 61 -- 1 -- n, 61 -- 2 -- n, 61 -- 3 -- n and 61 -- 4 -- n to four flag registers 51 -- 1 -- n, 51 -- 2 -- n, 51 -- 3 -- n and 51 -- 4 -- n. Thus, the flag registers 51 -- 1 -- n, 51 -- 2 -- n, 51 -- 3 -- n and 51 -- 4 -- n store a logical value "0" indicating that effective data group have been recorded therein.
As the flag registers 51 -- 1 -- n, 51 -- 2 -- n, 51 -- 3 -- n and 51 -- 4 -- n associated with a group number n store a logical value "0", the plural-selection separating circuits . . . , 52 -- 1 -- n, 52 -- 2 -- n, . . . , 52 -- 1 -- n+1, . . . , may detect the highest priority of one (in this case, word memory group associated with group number n+1) from among the word memory groups associated with the flag registers storing the empty flag "1", except for the word memory group associated with group number n.
According to the embodiment of the invention shown in FIG. 8, upon receipt of information indicating the fact that none of the word memory groups stores a desired data group, the additional writing control circuit 72 automatically writes a logical value "0" of flag for releasing the empty state into the flag register associated with the highest priority of word memory group (in this case, word memory group associated with group number n). The present invention is not restricted to this embodiment. It is acceptable to release the empty state of the highest priority of word memory group in such a manner that the additional writing control circuit 72 is arranged to permit a predetermined control signal to be entered from the exterior, and upon receipt of the control signal from the exterior the empty state is released.
The present invention is not limited to the particular embodiments described above. Various changes and modifications may be made within the spirit and scope of the invention. | An associative memory is capable of performing at high speed a registration of unregistered data. Retrieval data is stored at the same time when a retrieval is carried out. | 6 |
BACKGROUND AND SUMMARY
[0001] 1. Field
[0002] This invention relates, in general, to a memory device, and more particularly a memory device adapted to be connected in a daisy chain and having a data input port and output port that can be selectively enabled, and a memory module and memory system including the same.
[0003] 2. Description
[0004] In general, a memory system includes a memory controller and a plurality of memory module connected to the memory controller. As memory systems having a higher density are demanded, an increasing number of memory modules are employed. Although a memory system with higher density can be obtained by using more memory modules, the capacitive loading of each of the signal lines between the memory controller and memory modules increases. This, in turn, limits the operating speed of the memory system. For this reason, the number of memory devices connected to one data signal line is limited, for example, to eight devices in a memory system employing synchronous dynamic random access memory (SDRAM) to four devices in a memory system employing double data rate (DDR) SDRAM, and to two devices in a memory system employing DDR2/3 SDRAM.
[0005] To solve the foregoing problem, a memory system employing a point-to-point (PTP) connection between a memory controller and a memory module has been adopted in memory system architectures. This arrangement is also sometimes referred to as a “daisy chain.” Also, in this PTP arrangement, to increase the density of memory system the memory devices on one memory module employ a stacking package technology including lower memory device 132 - 1 and upper memory device 134 - 1 and each memory device is connected by the PTP arrangement.
[0006] FIG. 1A is a block diagram of an exemplary memory system 100 having a daisy chain structure. Memory system 100 includes a memory controller 110 and a memory module 120 . Memory module 120 includes a plurality of memory groups 130 - 1 ˜ 130 - n . In turn, each memory group 130 - i includes a primary memory device 132 - i and a secondary memory device 134 -I which are connected together in a daisy chain or PTP arrangement.
[0007] Memory controller 110 includes first output ports (Tx 1 ˜Txn) to output commands, addresses, and write data (C/A/WD) to memory module 120 , and first input ports (Rx 1 ˜Rxn) to input read data from memory module 120 .
[0008] In the memory system 100 : C/A/WD indicates merged signal lines for command and addresses and write data for write operations; RD indicates read data lines for read operations; Rx_p indicates an input port of primary memory device 132 - i ; Rx_s indicates an input port of secondary memory device 134 - i ; Tx_p indicates an output port of primary memory device 132 -I for sending command and addresses and write data; Tx_rdp indicates an output port of primary memory device 132 - i for outputting read data; Rx_rdp indicates an input port of primary memory device 132 - i ; Rx_rds indicates an input port of secondary memory device 134 - i for receiving read data; and Tx_rds indicates an output port of secondary memory device 134 - i for outputting read data. The input ports Rx_rdp of primary memory devices 132 - 1 ˜N are all disabled based upon the memory devices' connection as primary memory devices, rather than secondary memory devices, in the configuration of memory system 100 .
[0009] Operationally, a read operation of memory system 100 will be explained with reference to FIG. 1A . Consider a case where data is being read out of a primary memory device 132 - i to memory controller 110 . In that case, read data of the memory device 132 - i is transferred to memory controller 110 through the Tx_rdp port of primary memory device 132 - i , the Rx_rds port of secondary memory device 134 - i , and the Tx_rds port of secondary memory device 134 - i , sequentially in that order.
[0010] Now, for a read data operation, the Rx_rds port and Tx_rds port of secondary memory device 134 - i are always enabled or activated. That is, because secondary memory device 134 - i doesn't know when a read operation for primary memory device 132 - i occurs and when it will receive the read data from primary memory device 132 - i and repeat the read data to memory controller 110 , the circuits comprising the Rx_rds port and Tx_rds port of secondary memory device 134 - i should always be in an operating condition.
[0011] Accordingly, power consumption in memory system 100 is larger than necessary and therefore wasted
[0012] FIG. 1B is a block diagram of another exemplary memory system 150 having a daisy chain structure.
[0013] Memory system 150 is configured the same as memory system 100 of FIG. 1A , except for the following differences.
[0014] While the signal line for commands, addresses, and write data (C/A/WD) is merged in memory system, 100 of FIG. 1A , the signal lines for commands and addresses (C/A) and the signal lines for write data (WD) are separated from each other in memory system 150 of FIG. 1B .
[0015] Therefore, in memory system 150 of FIG. 1B , the input ports Rx_rdp of the primary memory devices 132 - 1 ˜N are all enabled to receive write data from memory controller 110 . Also in a write operation for writing data to secondary memory device 134 - i , primary memory device 132 - i repeats the write data from memory controller 110 to secondary memory device 134 - i through the output port Tx_rdp of primary memory device 132 - i.
[0016] That is, the input port Rx_rdp and the output port Tx_rdp of the primary memory device 132 - i are always enabled or activated to repeat write data to secondary memory device 134 - i because primary memory device 132 - i doesn't know when it will have to repeat the write data and output the write data to secondary memory device 134 - i.
[0017] Accordingly, power consumption in memory system 150 is larger than necessary and therefore wasted.
[0018] Accordingly, it would be advantageous to provide a memory device capable of selectively enabling/disabling an input port and/or an output port depending upon whether the port is needed for a current operation being performed in a memory system in which the memory device operates. It would also be advantageous to provide a memory module including a plurality of such memory devices. It would further be advantageous to provide a memory system including a plurality such a memory module including such a plurality of memory devices.
[0019] In one aspect of the invention, a memory device is adapted to be connected in a daisy chain with a memory controller and one or more other memory devices. The memory device comprises: a plurality of memory cells; a data input port adapted to receive read data; a data output port adapted to output the read data; a command/address input port adapted to receive a command and address packet; a decoder adapted to receive and decode the command and address packet and to output one or more detection signals, wherein when the command and address packet includes a read command, the one or more detection signals indicate whether the read command is intended for memory cells of the memory device, or for another memory device in the daisy chain; and a port controller adapted to selectively enable and disable at least one of the data input port and the data output port in response to at least one of the one or more detection signals from the decoder.
[0020] In another aspect of the invention, a memory module comprises a plurality of memory devices connected in a daisy chain. Each memory device comprises: a plurality of memory cells; a data input port adapted to receive read data; a data output port adapted to output the read data; a command/address input port adapted to receive a command and address packet; a decoder adapted to receive and decode the command and address packet and to output one or more detection signals, wherein when the command and address packet includes a read command the one or more detection signals indicate whether the read command is intended for memory cells of the memory device, or for one of the other memory device(s) in the daisy chain; and a port controller adapted to selectively enable and disable at least one of the data input port and the data output port in response to at least one of the one or more detection signals from the decoder.
[0021] In a further aspect of the invention, a memory system includes: a memory controller; and at least one memory module. Each memory module includes a plurality of memory devices connected in a daisy chain with the memory controller. Each memory device comprises: a plurality of memory cells; a data input port adapted to receive read data; a data output port adapted to output read data; a command/address input port adapted to receive a command and address packet; a decoder adapted to receive and decode the command and address packet and to output one or more detection signals, wherein when the command and address packet includes a read data command the one or more detection signals indicate whether the read data command is intended for memory cells of the memory device, or for one of the other memory device(s) in the daisy chain; and a port controller adapted to selectively enable and disable at least one of the data input port and the data output port in response to at least one detection signal from the decoder.
[0022] In yet another aspect of the invention, a memory device is adapted to be connected in a daisy chain with a memory controller and one or more other memory devices. The memory device includes at least one data input port and at least one data output port for communicating data along the daisy-chain between the memory devices and the memory controller. The memory device is adapted to selectively enable/disable at least one of the data input or data output ports in response to whether a command received from the memory controller is intended for the memory device, or for one of the other memory devices.
[0023] In still another aspect of the invention, a memory system includes: a memory controller; and at least one memory module. Each memory module includes a plurality of memory devices connected in a daisy chain with the memory controller. Each memory device includes at least one data input port and at least one data output port for communicating data along the daisy-chain between the memory devices and the memory controller, the memory device being adapted to selectively enable/disable at least one of the data input or data output ports in response to whether a command received from the memory controller is intended for the memory device, or for one of the other memory devices.
[0024] In a still further aspect of the invention, a memory device is adapted to be connected in a daisy chain with a memory controller and one or more other memory devices. The memory device comprises: a plurality of memory cells; a data input port adapted to receive read data; a data output port adapted to output read data; a command/address input port adapted to receive a command and address packet; a decoder adapted to receive and decode the command and address packet and to output a self read detection signal and a repeat read detection signal, wherein when the command and address packet includes a read command intended for memory cells of the memory device, then the self read detection signal is activated and the repeat read detection signal is inactivated, and when the command and address packet includes a read command intended for another memory device in the daisy chain which is connected to pass the read data to the memory controller through the memory device, then the self read detection signal is inactivated and the repeat read detection signal is activated; and a port controller adapted to selectively enable and disable at least one of the data input port and the data output port in response to at least one of the self read detection signal and the repeat read detection signal.
[0025] In an even further aspect of the invention, a memory device is adapted to be connected in a daisy chain with a memory controller and one or more other memory devices. The memory device comprises: a plurality of memory cells; a data input port adapted to receive write data; a data output port adapted to output the write data; a command/address input port adapted to receive a command and address packet; a decoder adapted to receive and decode the command and address packet and to output one or more detection signals, wherein when the command and address packet includes a write command the one or more detection signals indicate whether the write command is intended for memory cells of the memory device, or for one of the other memory device(s) in the daisy chain; and a port controller adapted to selectively enable and disable at least one of the data input port and the data output port in response to at least one detection signal from the decoder.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIGS. 1A-B are block diagrams of two memory systems each having a daisy chain arrangement.
[0027] FIG. 2 is a functional block diagram of one embodiment of a memory device.
[0028] FIG. 3 shows one embodiment of a port controller that may be employed in the memory device of FIG. 2 .
[0029] FIG. 4 shows one embodiment of a command, address and write data (C/A/WD) packet format.
[0030] FIG. 5A is a high level block diagram of a memory system that may include the memory device of FIG. 2 .
[0031] FIG. 5B is a timing diagram illustrating a read operation of the memory system of FIG. 5A .
[0032] FIG. 6 is a functional block diagram of another embodiment of a memory device.
[0033] FIGS. 7A-B show two different embodiments of a port controller that might be employed in the memory device of FIG. 6 .
[0034] FIG. 8A shows a block diagram of one embodiment of a memory system, which might include the memory device of FIG. 2 .
[0035] FIG. 8B shows a block diagram of a second embodiment of a memory system, which might include the memory device of FIG. 6 .
DETAILED DESCRIPTION
[0036] FIG. 2 is a functional block diagram of one embodiment of a memory device 200 . Memory device 200 includes: first input port 202 ; first output port 204 ; ID register 206 ; packet decoder 208 ; port controller 210 ; data input port 212 ; memory core 214 ; selector 216 ; and data output port 218 . First input port 202 includes buffer B 1 , and first output port 204 includes buffer B 2 . Data input port 212 includes buffer B 3 and serial-to-parallel-converter (SPC) 213 . Data output port 214 includes buffer B 4 and parallel-to-serial-converter 219 .
[0037] Referring to FIG. 2 , when memory device 200 is used as a primary memory device in a daisy chain structure, then first input port 202 receives a command/address/write data (C/A/WD) packet from a memory controller, and generates an internal C/A/WD packet. On the other hand, when memory device 200 is not used as a primary memory device (e.g., is used as a secondary memory device), then first input port 202 receives a C/A/WD packet from a preceding memory device in the daisy chain (e.g., a primary memory device) and generates an internal C/A/WD packet.
[0038] First output port 204 receives the internal C/A/WD packet from first input port 202 and outputs the internal C/A/WD packet to a next memory device in the daisy chain. When memory device 200 is a last memory device in the daisy chain, then first output port 204 remains in a disabled state, perhaps by one or more pins on memory device 200 detecting a voltage level indicating the last device “slot” in the daisy chain. Other arrangements are of course possible.
[0039] ID Register 206 stores device identification information for the daisy chain structure in which memory device 200 is currently provided. For example, if a daisy chain includes four memory devices 200 , then each memory device 200 stores one of “00”, “01”, “10” and “11” in ID Register 206 . Again, memory device 200 may determine its position in the daisy chain by detecting a voltage level(s) on one or more pins of memory device 200 , indicating the corresponding device “slot” in the daisy chain. Other arrangements are of course possible.
[0040] Packet decoder 208 receives the internal C/A/WD packet. In addition to command, address, and write data (in a data writing operation), a C/A/WD packet also includes device identification (ID) information. Packet decoder 208 compares the ID information included in the C/A/WD packet and the ID information stored in ID Register 206 , and in response to the comparison generates command, address, and control signals (SRD, RP_RD) for operation of memory device 200 .
[0041] The SRD signal is activated when the ID information included in the C/A/WD packet and the ID information stored in ID Register 206 are same, and the decoded command is for a read operation. That is, the SRD signal is activated to have a logic “high” state when a self read command is detected by packet decoder 208 . On the other hand, the RP_RD signal is activated when the ID information included in the C/A/WD packet and the ID information stored in ID Register 206 are not same, and the decoded command is for read operation. That is, the RP_RD signal is activated to have a logic “high” state when a read command for another memory device is detected by packet decoder 208 .
[0042] The point of time when the SRD signal is activated may be determined by a CL (CAS Latency) of memory device 200 , and the duration for which the SRD signal is activated may be decided by a BL (Burst Length). CL is the time, measured as a number of clock cycles, from receiving a read command to outputting read data. BL is the number of data which is successively outputted or inputted to/from memory device.
[0043] The point of time when the RP_RD signal is activated may be determined by the CL (CAS Latency) of a preceding memory device in a daisy chain, and the time for repeating data between memory devices. The duration for which the RP_RD signal is activated may be determined by a BL (Burst Length) of a preceding memory device in the daisy chain.
[0044] Port controller 210 receives the SRD and RP_RD signals, and outputs data input port and data output port enable signals (Rx_en, Tx_en) for determining when data input port 212 and data output port 218 are enabled. In particular, the data input port enable signal (Rx_en) is activated in response to RP_RD, and the data output port enable signal (Tx_en) is activated in response to RP_RD or SRD.
[0045] As noted above, data input port 212 includes buffer B 3 and a Serial-to-Parallel-Converter (SPC) 213 and is enabled by the Rx_en signal. SPC 213 parallelizes a serial read data packet from a preceding memory device in a daisy chain, and outputs 1st read data to a selector 216 . If memory device 200 is used as a primary memory device, the circuits comprising data input port 212 , i.e., the buffer B 3 and SPC 213 , are always disabled.
[0046] Memory core 214 outputs 2nd read data in response to the read command and address from packet decoder 208 .
[0047] Selector 216 selects and outputs one of 1st read data and 2nd read data to the data output port is response to the SRD signal from packet decoder 208 . That is, selector 216 outputs 2nd read data to data output port 218 when packet decoder 208 detects a self read command, and outputs 1st read data when packet decoder 208 detects a read command for another memory device.
[0048] As noted above, data output port 218 includes Parallel-to-Serial-Converter (PSC) 219 and buffer B 4 and is enabled in response to the Tx_en signal. PSC 219 serializes the parallel read data from selector 216 , and outputs the serial read data from memory device 200 .
[0049] FIG. 3 shows one embodiment of port controller 210 that may be employed in the memory device of FIG. 2 . Port controller 210 includes a delay element “R” and an OR logic gate 211 . OR Logic gate activates the Tx_en signal to enable data output port 218 when either the SRD signal or the RP_RD is activated. Meanwhile the Rx_en signal is activated to enable data input port 212 when the RP_RD signal is activated. It is desirable for delay element “R” to have a delay that is less than the sum of the delay through data input port 212 and selector 216 .
[0050] FIG. 4 shows one embodiment of a command, address, and write data (C/A/WD) packet format. As shown in FIG. 4 , the C/A/WD packet can be transferred by 6 pins, and each pin may provide up to 8 bits of information synchronized with the clock signal. The C/A/WD packet may be for an active operation, a read operation, a write operation etc. If the C/A/WD packet is for write operation, the packet may be extended to include write data in the same manner.
[0051] The first bit of the C/A/WD packet includes a command type indicated C 0 ˜C 2 and device identification information CS 0 ˜CS 1 . The second and third bits of the C/A/WD packet include BA 0 ˜BA 3 address bits for bank addresses, and A 0 ˜A 13 address bits to select a specific memory cell.
[0052] FIG. 5A is a high level block diagram of a memory system 500 that may include a memory device 200 as shown in FIG. 2 .
[0053] Memory system 500 includes a memory controller 510 and a memory group having a primary memory device 200 p and a secondary memory device 200 s.
[0054] In FIG. 5A , CRD 0 denotes a C/A/WD packet from memory controller 510 to primary memory device 200 p , and CRD 1 denotes a C/A/WD packet from primary memory device 200 p to secondary memory device 200 s . RD 0 denotes read data from primary memory device 200 p and RD 1 denotes read data from secondary memory device 200 s . RD 1 can be RD 0 when read operation is for primary memory device 200 p.
[0055] Although FIG. 5A shows only one memory group, the memory system may include more than one memory group. Also, although each memory group of the memory system in FIG. 5A has two memory devices, this is used for illustrative purposes only and that the teaching of this invention can be extended to other memory group having more than two memory devices in a daisy chain.
[0056] FIG. 5B is a timing diagram illustrating a read operation of the memory system 500 of FIG. 5A .
[0057] In FIG. 5B , the CL and BL of primary memory device 200 p and secondary memory device 200 s are 6 clocks and 2 clocks respectively.
[0058] Referring to FIGS. 2-5 , a successive read operation of primary and secondary memory devices 200 p and 200 s in memory system 500 will be explained.
[0059] Primary memory device 200 p receives CRD_P and CRD_S successively and repeats and outputs the CRD_P and CRD_S. Packet decoder 208 decodes the CRD_P packet and activates the SRD_P signal because the device identification information included in the CRD_P and the identification information stored in IDR 206 of memory device 200 p are the same.
[0060] The Tx_en signal of primary memory device 200 p (Tx_en_p) is activated responsive to the SRD_P signal after a pre-determined time of the CL lapses. The duration of activation of Tx_en_p is long enough to output all of the read data as determined by the BL.
[0061] First read data (RD_ 0 ) from primary memory device 200 p is transferred in response to the Tx_en_p signal to data input port 212 of secondary memory device 200 s.
[0062] Secondary memory device 200 s receives the CRD_P and CRD_S packets successively through primary memory device 200 p after a repeating time delay tRP.
[0063] Secondary memory device 200 s decodes the CRD_P packet, detects that the read command is for another memory device (i.e., primary memory device 200 s ) and activates the RP_RD_s signal. Port controller 210 of secondary memory device 200 s activates the Rx_en and the Tx_en signals in response to the RP_RD_s signal. Data input port 212 of secondary memory device 200 s receives the first read data (RD_ 0 ) and transfers RD_ 0 to data output port 218 through the selector 216 . Data output port 218 of secondary memory device 200 s outputs the RD_ 0 data to memory controller 510 in response to the Tx_en signal.
[0064] Also, secondary memory device 200 s decodes the CRD_S packet, detects self read command and activates the SRD_s signal. Port controller 210 maintains the activation of the Tx_en signal in response to the SRD_s signal until the second read data RD_ 1 from primary memory device 200 p is output to memory controller 510 .
[0065] By the process outlined above, data output port 218 of secondary memory device 200 s can output RD_ 0 and RD_ 1 packets successively to memory controller 510 .
[0066] Accordingly, as the data input port and data output port of memory device 200 comprising a daisy chain structure can be selectively operated by detecting a command for other memory devices as well as commands for itself, power consumption of the data input and output ports can be reduced because the data input and output port operate only when they are needed.
[0067] FIG. 6 is a functional block diagram of another embodiment of a memory device 600 . The memory device 600 of FIG. 6 may be used in a memory system similar to memory system 150 of FIG. 1B , where the signal lines for commands and addresses (C/A) and the signal lines for write data (WD) are separated from each other. While the signal lines for commands and addresses, and the signal lines for write data are separated each other, the write data lines are merged with the read data lines. Accordingly, the interface for memory device 600 is different from for memory device 200 .
[0068] Referring to FIG. 6 , only the differences from memory device 200 will be explained.
[0069] Packet decoder 608 decodes a C/A packet and detects whether a write command is for its own memory device 600 , or for another memory device. If the decoded command is for a write operation and the ID information in the C/A packet matches the ID information in IDR 206 , then the SWR (self write) signal is activated. If the decoded command is for a write operation and the ID information in the C/A packet does not match the ID information in IDR 206 , then the RP_WR (repeating write data) signal is activated.
[0070] Port controller 610 receives the SRD signal, the RP_RD signal, the SWR signal, and the RP_WR signal from packet decoder 608 , and outputs Rx_en and Tx_en signals to data input port 212 and data output port 218 , respectively. In addition, port controller 610 activates the Rx_en and Tx_en signals in response to the SRD signal and the RP_RD signal, as in the memory device 200 of FIG. 2 , but it also activates the Rx_en signal when the SWR signal is activated, and activates the Rx_en and Tx_en signals when the RP_WR signal is activated.
[0071] The point of time when the Rx_en signal is activated in response to the SWR signal may be determined by the Write Latency (WL), and the duration of activation of the Rx en signal in response to SWR may be also decided by a Burst Length (BL). Also, the point of time when the Tx_en is activated in response to RP_WR signal may be decided by the WL and a repeating time, and the duration of activation of the Tx_en signal in response to the RP_WR signal may be also decided by a BL.
[0072] Data input port 212 of memory device 600 is the same as that of memory device 200 of FIG. 2 . However, data input port 212 of memory device 600 receives write data (WD) from the memory controller when memory device 600 is used as a primary memory device, and receives write data from a preceding memory device in a daisy chain when it is not used as the primary memory device.
[0073] Switch 612 transfers the write data received from data input port 212 to memory core 214 or selector 216 in response to the SWR signal. That is, switch 612 transfers write data to memory core 213 only when a self write command is detected.
[0074] Selector 216 outputs self read data in response to the SRD signal only when a self read command is detected, otherwise it outputs the read data or write data from a preceding memory device in a daisy chain to either a subsequent memory device, or the memory controller in the case of a read command, when it is the last memory device in the daisy chain.
[0075] FIGS. 7A-B show two different embodiments of a port controller 610 that might be employed in the memory device of FIG. 6 .
[0076] While FIG. 7A illustrates a configuration for port controller 610 when memory device 600 is used as a primary memory device in a daisy chain, FIG. 7B illustrates a configuration for port controller 610 when memory device is not used as a primary memory device.
[0077] Referring FIG. 7A , the Rx_en signal is activated in response to the SWR signal or the RP_WR signal, and the Tx_en signal is activated in response to the SRD signal or the RP_WR signal. The Tx_en signal can be activated through a delay element “R” after the RP_WR signal is activated. It is desirable for the delay element “R” to have a delay that is less than or equal to a delay equaling the sum of the delays of data input port 212 , switch 612 , and selector 216 .
[0078] Referring FIG. 7B , the Rx_en signal is activated in response to the SWR signal, the RP_WR signal, and the RP_RD signal, and the Tx_en signal is activated in response to the SRD signal, the RP_RD signal, and the RP_WR signal. The Tx_en signal can be activated through a delay element “R” after the RP_WR signal or the RP_RD signal is activated. It is desirable for the delay element “R” to have a delay that is less than or the same as the sum of the delays of data input port 212 , switch 612 , and selector 216 .
[0079] FIG. 8A shows a block diagram of one embodiment of a memory system 800 , which might include the memory device 200 of FIG. 2 .
[0080] Although the memory system 800 shows just one memory group (S 0 ), in general the memory system may have a plurality of memory groups.
[0081] Memory group S 0 of memory system 800 includes primary (P), secondary (S), third (T) and fourth (F) memory devices 200 . IDR 206 of primary memory device 200 stores self ID information (ID 0 ). IDR 206 of secondary memory device 200 stores self ID information (ID 1 ) and ID information (ID 0 ) of primary memory device 200 . IDR 206 of third memory device 200 stores: self ID information (ID 2 ), ID information (ID 0 ) of primary memory device 200 , and ID information (ID 1 ) of secondary memory device 200 . IDR 206 of fourth memory device 200 stores: self ID information (ID 3 ), ID information (ID 0 ) of primary memory device 200 , ID information (ID 1 ) of secondary memory device 200 , and ID information (ID 2 ) of third memory device 200 .
[0082] Each memory device 200 compares device identification information included in a command packet and stored ID information in IDR 206 of the memory device 200 and determines form the comparison whether a read command is for itself or for another memory device in a daisy chain. Whether or not data input port 212 and/or data output port 218 should be enabled can be determined selectively by the result of the comparison.
[0083] For example, data input port 212 and data output port 218 of secondary memory device 200 can be enabled when secondary memory device 200 detects a read command for primary memory device 200 . Also, data input port 212 and data output port 218 of third memory device 200 can be enabled when third memory device 200 detects a read command for primary memory device 200 or secondary memory device 200 . Furthermore, data input port 212 and data output port 218 of fourth memory device 200 can be enabled when fourth memory device 200 detects a read command for primary memory device 200 , secondary memory device 200 , or third memory device 200 .
[0084] FIG. 8B shows a block diagram of a second embodiment of a memory system, which might include the memory device 600 of FIG. 6 .
[0085] Each of memory devices 600 comprising a daisy chain has an IDR 206 which stores all ID information of all of the memory devices 600 in the daisy chain.
[0086] Each memory device 600 compares device identification information included in a command packet, with the stored ID information, and determines as a result of that comparison whether a write command is for itself or another memory device, and also whether a read command is for itself or another memory device. Whether or not data input port 212 and/or data output port 218 should be enabled can be determined selectively by the result of the comparison when a read operation or a write operation is performed for a memory device 600 in the daisy chain.
[0087] For example, data input port 212 and data output port 218 of primary memory device 600 can be enabled when primary memory device 200 detects a write command for secondary memory device 600 , or third memory device 600 , or fourth memory device 600 . Also, data input port 212 and data output port 218 of secondary memory device 600 can be enabled when secondary memory device 600 detects a write command for third memory device 600 or fourth memory device 600 . Furthermore, data input port 212 and data output port 218 of third memory device 600 can be enabled when third memory device 600 detects a read command for fourth memory device 600 .
[0088] As the number of memory devices in a daisy chain increase, the benefits described above also increase.
[0089] While preferred embodiments are disclosed herein, many variations are possible which remain within the concept and scope of the invention. Such variations would become clear to one of ordinary skill in the art after inspection of the specification, drawings and claims herein. The invention therefore is not to be restricted except within the scope of the appended claims. | A memory device is adapted to be connected in a daisy chain with a memory controller and one or more other memory devices. The memory device includes at least one data input port and at least one data output port for communicating data along the daisy-chain between the memory devices and the memory controller. The memory device is adapted to selectively enable/disable at least one of the data input or data output ports in response to whether a command received from the memory controller is intended for the memory device, or for one of the other memory devices. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a device for testing material on a test object having at least electrically conducting and ferromagnetic material parts, the test object having at least one technical surface with at least one electromagnetic ultrasonic transducer (EMUS) provided with at least one magnet and at least one eddy current coil.
2. Description of the Prior Art
Electromagnetic ultrasonic transducers are used in a known manner for the purpose of non-destructive material testing and measurement of test objects comprising electrically conducting materials which moreover possess ferromagnetic properties.
Basically electromagnetic ultrasonic transducers can be differentiated into two types: on the one hand, those with which produce so-called horizontally polarized shear waves which are able to propagate inside the test object predominantly parallel to the coupling-in surface; and on the other hand, ultrasonic transducers for generating in the test object so-called freely propagating ultrasonic waves preferably propagating inside the test object perpendicular to the coupling-in surface. In both instances, excitation of ultrasonic waves inside a test object results from the occurrence of magnetostriction and Lorenz forces inside the test object material, which can be generated by the presence of a temporally largely constant magnetic field overlapping with an electromagnetic alternating field generated by an electro-magnetic alternating current.
A typical setup for exciting ultrasonic waves according to the so-called EMUS principle is shown in FIGS. 8 a and 8 b . Common EMUS transducers 3 comprise a permanent magnet 1 and an eddy current coil 2 , which are designed as one unit for joint handling. Usually the eddy current coil 2 is designed as a rectangular flat coil or a spiral flat coil each of which have an electrically conductive strip and is attached to a magnetic pole side of the permanent magnet 1 in such a manner that a permanent magnetic field passes vertically through the coil 2 . If the aforementioned EMUS transducer 3 is placed on an electrically conducting ferromagnetic test object 4 , the permanent magnetic field overlaps inside the test object with an eddy current field generated by the eddy current coil, on the one hand, generating magnetostrictive effects due to the overlapping of the magnetic field components of the eddy current field with the permanent magnetic field entering vertically through the surface of the test object and, on the other hand generating the Lorenz forces due to the eddy currents induced in the test object, which then generate pressure waves occurring normally in relation to the surface of the test object as well as radially polarized shear waves capable of propagating as ultrasonic waves inside the test object. Both types of ultrasonic waves, that is the ultrasonic waves propagating normally in relation to the surface of the test object and ultrasonic waves propagating in longitudinal direction to the surface of the test object due to radially polarized shear waves are suited according to the state of the art for testing faults, for example detecting cracks inside the test object, as well as for measuring the thickness of the wall of the test object.
Since in use eddy current coils are very sensitive to outside mechanical influences, the eddy current coils must principally be protected against mechanical wear, which is difficult in particular due to the fact that in ferromagnetic test objects the eddy current coil located between the permanent magnet and the test object is pressed onto the surface of the test object by the magnetic forces of attraction and is therefore subject to considerable fretting.
In this context, German Patent 35 11 076 A1 describes a test pig for electromagnetic testing of the walls of steel pipes, such as, for example as part of nondestructive testing of wall weaknesses due to rusting of the pipe walls. A pig, which is described in detail therein, is provided with electromagnets, which are distributed uniformly around the circumference, each comprising two measuring heads which are axially aligned to each other, a yoke connecting the measuring heads and a magnetizing coil on the measuring heads, with the field of each electromagnet running parallel to the center axis of the pipe. For ultrasonic measurement, an eddy current coil, to which are applied strong and very rapidly rising current pulses, is disposed directly at least on one of the poles, and the measuring heads. The pipes of pipelines are provided with circumferential seams at the adjoining parts of two adjacent pipe pieces. When the above briefly described test pig runs over the seams during continuous inspection, the circumferential seams subject the electromagnetic transducer to impacts which, moreover, are markedly intensified by the magnetic forces prevailing between the electromagnets and the wall of the pipes. The previously described fretting and the additional impacts to the electromagnetic ultrasonic transducer, in particular to the eddy current coil, lead to a short lifetime of the EMUS transducer, which needs to be addressed.
Although fretting can be reduced by decreasing the magnetic forces of attraction prevailing between the EMUS transducer and the to-be-inspected test object, for example by decreasing the magnetic field induction, this measurement would also immediately lead to distinctly diminishing the EMUS transducer's efficiency, that is force density induced to generate ultrasound inside the test object reduces in the same way, due to which the detection sensitivity in receiving scattered or reflected ultrasonic waves diminishes to the same extent.
Japanese Patent 111 33 003 describes a device for inspecting material using ultrasound which is suited in particular for inspecting the material of pipes. According to claim 4 therein, the device comprises single permanent magnets which are arranged to form a ring of segments with an outer and an inner circumferential edge. The adjacent permanent magnets have opposite magnetic poles at the outer and inner circumferential edge. Disposed in windings on the outer circumferential edge of this ring is an electrical strip conductor of at least one eddy current coil. The device is introduced in operation into a pipe that the outer circumferential edge with the strip conductors slides along the inner wall of the pipe, leading to corresponding fretting on the strip conductors.
U.S. Pat. No. 4,898,034 describes a device for testing hot materials, such as metals and ceramics, using ultrasound. An embodiment uses an agent made of zircon which is in contact with the hot material to be examined. Furthermore, a coupling medium (borax) is in contact with the hot material and the zircon agent. The zircon agent and the coupling medium receives ultrasonic waves propagating from the hot material through the coupling medium and the zircon agent. In the embodiment shown in FIG. 1 of U.S. Pat. No. 4,898,034, the zircon agent is designed as a ring with an outer and an inner circumferential edge. In operation, the outer circumferential edge of the ring is rolled over the hot material to be examined. A lever, which is attached to the rotational axis of the zircon ring, holds the ultrasound transmitter constantly as shown in downward perpendicular position. In this manner the ultrasound transmitter including the eddy current coil attached to it is pressed against the inner circumferential edge of the ring, leading once again to fretting of the ultrasound transmitter.
SUMMARY OF THE INVENTION
The present invention is a device for material testing of a test object having at least electrically conducting and ferromagnetic material parts based on electromagnetic ultrasonic excitation and using an electromagnetic ultrasonic transducer array (EMUS) so that eddy current coils required for generating eddy currents are not subject to any or minimum fretting. Furthermore, conducting material testing on the test object continuously is possible.
Contrary to the usual electromagnetic ultrasonic transducer arrays which are provided with permanent magnets or electromagnets and at least one eddy current coil and in which the eddy current coil is moved in a sliding manner in order to inspect the material at the surface of a test object and therefore are subject to slip friction wear, the electromagnetic ultrasonic transducer according to the present invention provides a new eddy current coil design which is combined with a rolling member which is rolled over the surface of a test object. The electromagnetic ultrasonic transducer, hereinafter EMUS transducer, according to the present invention is subject to less wear compared to standard versions. The rolling friction forces occurring in the EMUS transducer according to the present invention are substantially less than the slip friction forces which considerably increases the lifetime of the EMUS transducer according to the present invention.
If a prior art EMUS transducer is moved by slipping over an uneven surface of a test object in a slipping process, the eddy current coil therein is subject to increased wear due to the unevenness of the surface of the test object, such as, for example, due to bulging at the welding seams. With the EMUS transducer according to the present invention, surface unevenness is simply rolled over without lasting impairment of the eddy current coil.
Another advantage of the EMUS transducer according to the present invention is conducting material inspection continuously as will be described in detail in the following.
Thus a device for testing material on a test object which comprises at least electrically conducting and ferromagnetic material parts and which possesses at least one technical surface having an electromagnetic ultrasonic transducer provided with a magnet which is permanent or an electromagnet and at least one eddy current coil according to the invention includes at least one eddy current coil having at least one electrical strip conductor which is disposed at or parallel to a surface area of a rolling member which is disposed on the technical surface of the test object which can be rolled over.
In a particularly preferred embodiment, the rolling member, which preferably is a disk, reel, wheel or ball, is combined with the permanent magnet or electromagnet in such a manner that the rolling member, the permanent magnet or electromagnet as well as the at least one eddy current coil which is attached on the rolling member or connected to the rolling member, is moved uniformly in relation to the test object.
Another preferred embodiment provides for separate handling of the at least one permanent magnet or electromagnet and the combination of rolling member and eddy current coil. Further details to the preferred embodiments are described in the following with reference to the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is made more apparent in the following by way of example using preferred embodiments with reference to the accompanying drawings without the intention of limiting the scope or spirit of the invention.
FIG. 1 shows a schematic representation of EMUS transducers having a permanent magnet and an eddy current coil with elliptically shaped strip conductor loops, attached to the circumferential edge of a rolling member;
FIG. 2 shows a schematic representation of an EMUS transducer having a permanent magnet and an eddy current coil with a strip conductor windings at the circumferential edge of a rolling member;
FIG. 3 shows a schematic representation of an EMUS transducer having a permanent magnet and two ferromagnetic return paths;
FIGS. 4 and 5 show a view of an EMUS transducer having two permanent magnets and an eddy current coil;
FIGS. 6 and 7 show a representation of an EMUS transducer having an electromagnet and a separate eddy current coil; and
FIGS. 8 a and b show a prior art EMUS transducer.
DETAILED DESCRIPTION OF THE INVENTION
The left representation in FIG. 1 shows a front view and the right representation shows a lateral view, of the EMUS transducer according to the present invention, which due to its principle of construction is also referred to as an EMUS wheel. The EMUS transducer is provided with a rolling member 5 which in the preferred embodiment is designed to be a ring or reel which is hollow inside and has an outer circumferential edge 51 . The rolling member 5 has a center axis of rotation A about which the rolling member 5 rolls relative to the technical surface 6 of the test object 4 . An eddy current coil 2 is wound along the circumferential edge 51 of the rolling member 5 as shown in the left representation. The eddy current coil 2 comprises a through-going electrical conductor including elliptical strip conductor loops 52 which are wrapped along the circumferential edge 51 of the rolling member 5 in such a manner that the entire circumferential edge 51 of rolling member 5 is covered by the loops 52 . It is obvious that when the current is applied to the strip conductors 52 , two immediately adjacent strip conductor loops 52 have current flowing in opposite directions. The alternative strip conductors 52 ′ are wound on the circumferential so that two strip conductors wound immediately adjacent to each other extend in the same direction. The strip conductor 52 and 52 ′ are each suited for effectively coupling in ultrasonic waves into the test object 4 .
Each EMUS transducer shown in FIG. 1 is provided with a permanent magnet 7 to introduce a temporally constant magnetic field into the test object. The permanent magnet 7 is attached to the axis of rotation A in such an asymmetrical manner that a magnetic pole, preferably the magnetic north pole N is disposed maximally close to the circumferential edge 51 of the rolling member 5 . When the rolling member rolls along the technical surface 6 of the object 4 , the magnetic north pole N of the permanent magnet 7 is drawn to the ferromagnetic test object 4 and, due to its rotational mobility, about the axis of rotation A always stays facing the test object 4 , so that the magnetic north pole is always directed downward. Thus the permanent magnet 7 generates a magnetic field whose magnetic field lines are always oriented perpendicular to the technical surface 6 of the test object 4 .
If the eddy current coil 2 is fed with pulsed current, eddy currents are induced in the test object which interact with the magnetic flow oriented normally to the technical surface 6 . Ultrasonic waves with circular polarization are generated in test object 4 by developing Lorenz forces. The ultrasonic waves propagate essentially perpendicular to the technical surface 6 inside the test object 4 .
The eddy current coil 2 also functions as a reception coil for the ultrasonic waves reflected back inside the test object 4 .
As an alternative to the strip conductors of the eddy current coil 2 depicted in FIG. 1 , FIG. 2 shows a variant of the EMUS transducer in which the eddy current coil 2 has electrical windings 53 which are each disposed around the circumferential edge 51 of the rolling member 5 . The design of the strip conductors 53 of the current coil 2 is shown in the left representation of FIG. 2 . Due to the alternative embodiment of the strip conductors 53 according to the preferred embodiment in FIG. 2 , ultrasonic waves with linear polarization are generated in the test object 4 . The ultrasonic waves however are due to the same excitation principle by Lorenz forces occurring as in the preferred embodiment according to FIG. 1 .
In both preceding embodiments of FIGS. 1 and 2 , the rolling member 5 is preferably not a metallic material. The rolling member 5 can, of course, also be made of a ferromagnetic and electrically conductive material. In this case, however, care must be taken that the strip conductors 52 or 53 of the eddy current coil 2 are electrically insulated from the rolling member 5 . It is also expedient, for further reduction of the rolling friction occurring between the rolling member 5 and the technical surface 6 , to provide a protective coat (not depicted) to protect the eddy current coils 52 or 53 .
In contrast to the preceding preferred embodiments of FIGS. 1 and 2 in which a temporally constant magnetic field is oriented perpendicular to the technical surface 6 of the test object 4 and is coupled into the test object 4 , the preferred embodiment of an EMUS transducer designed according to the invention depicted in FIG. 3 causes a magnetic field to be coupled into the technical surface 6 , which is oriented tangentially to the technical surface of test object 4 . FIG. 3 shows again in the left representation, a front view and in the right representation, a lateral view of the EMUS transducer 3 . In the preferred embodiment, the strip conductors of the eddy current coil 2 are wound around the surface of a cylindrical or rod-shaped permanent magnet 7 . Attached at the opposite N and S magnetic poles of the permanent magnet 7 are two disk rolling members 5 composed of ferromagnetic material, which is preferably a ferrosteel and which project radially outward from the axis of rotation of the permanent magnet 7 including the eddy current 2 . The disk rolling members 5 each act as a yoke which conducts the magnetic field lines so that a magnetic circuit including the ferromagnetic rolling members 5 and the test object is closed. Due to the magnetic return path, a magnetic field is coupled tangentially to the technical surface 6 inside test object 4 . The eddy currents excited by the eddy current coils 2 generate inside the test object 4 a secondary alternating magnetic field which overlaps with the constant magnetic field of the permanent magnet 7 . The ultrasonic waves are excited by the developing magnetostrictive effect and, like in the case of the embodiment according to FIG. 2 , have a linear polarization. The disk rolling members 5 , which enclose the permanent magnet 7 on both sides, have two functions. On the one hand the rolling members 5 act as a magnetic yoke and on the other hand they permit the ultrasonic transducers to roll over the technical surface 6 of the test object 4 , with the eddy current coils 2 always assume a constant distance from the technical surface 6 , due to which the strip conductors are subject to no mechanical wear from rolling friction.
FIGS. 4 and 5 show two further preferred embodiments of an EMUS transducer 3 according to the invention. These embodiments are provided with two permanent magnets 7 and 7 ′ and an eddy current coil 2 . The only difference in the designs of the two embodiments is in the eddy current coils 2 . The permanent magnets 7 and 7 ′ are attached with their opposing magnetic north poles N to the ferromagnetic rolling member 5 , which preferably is a ring or a wheel. Due to the opposite magnetic north poles N, a displacement of the magnetic field lines occurs in such a manner that they are coupled, via the ferromagnetic ring unit rolling member 5 , perpendicular to the technical surface 6 of the test object 4 . The ferromagnetic rolling member 5 acts simultaneously as a concentrator of the magnetic field by which the magnetic field at the contact points between the rolling member 5 and the technical surface 6 is coupled into the test object 4 in a concentrated manner. Moreover, the ultrasonic-wave excitation principle is the same as in the preferred embodiments in FIGS. 1 and 2 .
In order to improve closure of the magnetic circuit in the preferred embodiments shown in FIGS. 4 and 5 , a ferromagnetic end piece may be provided on the front magnetic south poles, which like the rolling member 5 comes into contact with the technical surface 6 of the test object 4 .
In some material testing applications using permanent magnets can be obviated, as for example material with testing on sheet metals. In this case electromagnets are preferable. FIGS. 6 and 7 show preferred embodiments each with separate arrangement between the electromagnet 7 and the eddy current coils 2 . The yoke-shaped electromagnet array 7 has two magnetic poles N and S which each can be placed on the technical surface 6 of the test object 4 to feed a tangential magnetic field. Provided in the area of the tangential magnetic field is a rolling member 5 at whose circumferential edge an eddy current coils 2 are provided. In the example of the FIG. 6 , the rolling member 5 is located on a top side of the test object facing away from the electromagnet array 7 . In the example according to FIG. 7 , both the electromagnet array 7 and the rolling member 5 are located on a common technical surface 6 of the test object 4 . The excitation principle of the ultrasonic waves inside the test object 4 is identical to that according to the preferred embodiment in FIG. 3 . The tangentially running magnetic field which is fed by the electromagnet 7 into the test object 4 interacts with the eddy currents and the alternating magnetic field in such a manner that, due to the occurrence of magnetostrictive effects, linear polarized ultrasonic waves are generated. Of course, eddy current coils 2 , designed as rolling members 5 , can be provided in the area of the tangential magnetic field. As in the preferred embodiments shown in FIGS. 6 and 7 , since no magnetic attraction forces act between the rolling member 5 and the technical surface 6 of the test object 4 , wear of the EMUS transducer is minimal.
Rolling the rolling member 5 along the circumferential edge on which the eddy current coils are disposed uniformly allows conducting continuous inspection in contrast to the hitherto used locally discrete EMUS testing arrangements. The invention, also referred to as EMUS wheel, is fundamentally suitable for an application to different fields such as for measuring the wall thickness and fault inspection of sheet metals, rails, pipes and pipelines as well as railroad wheels, oil containers or the outer walls of ships and other security containers. The EMUS transducer can also be combined with transport systems, for example so-called pig systems used in long-distant pipelines and the like to perform inspection.
LIST OF REFERENCES
1 permanent magnet
2 eddy current coil
3 EMUS transducer
4 test object
5 rolling member
6 technical surface
7 permanent magnet | A device is disclosed for material testing on a test object having at least electrically conducting and ferromagnetic material parts. The test object has at least one technical surface on which at least one electromagnetic ultrasonic transducer (EMUS) is rolled. The at least one transducer includes at least one permanent magnet or an electromagnet and at least one eddy current coil. The at least one eddy current coil has at least one electrical strip conductor which is disposed at or parallel to a surface area of a rolling member which can be rolled on the technical surface of the test object, with the surface area rolling along with the rolling member during rolling. | 6 |
FIELD OF THE INVENTION
The invention resides in the field of sewing machines where the thread tends to become knotted or tangled, and not run smoothly through the needle. Heretofore thread would often become knotted or entangled, either in association with the needle, or by itself. This was particularly true in the case of metallic thread. Metallic thread easily became knotted, as compared with other threads such as cotton, etc. with corresponding difficulties and annoyances so as to prevent the thread from running smoothly.
SUMMARY OF THE INVENTION
A main objective of the invention is to provide a guide to overcome the above objection, which can be easily applied to the sewing machine, and that does not require modification of the sewing machine itself to enable its application thereto.
The guide is so applied to the sewing machine by fitting it on the presser foot, which includes prongs extending generally horizontally, the guide having corresponding prongs fitted on those prongs.
Another object is to provide such a guide that is extremely simple and thereby easily applied to the presser foot of the sewing machine and held thereon mainly by the friction.
Still another object is to provide such a guide, whereby when it is applied to the sewing machine, and the thread is put in place in relation thereto, the thread provides a constant pressure to aid in retaining the guide on the presser foot.
BRIEF DESCRIPTIONS OF THE INDIVIDUAL FIGURES OF THE DRAWINGS
FIG. 1 is a fragmentary view of a sewing machine to which the guide is applied.
FIG. 2 is a fragmentary top view of the prongs of the sewing machine taken at line 2 — 2 of FIG. 1 .
FIG. 3 is an end view taken at line 3 — 3 of FIG. 1 .
FIG. 4 is a view taken at line 4 — 4 of FIG. 1 .
FIG. 5 is a perspective view of the thread guide of the invention.
FIG. 6 is a perspective view of the thread guide, but at an angle different from that of FIG. 5 .
FIG. 7 is a side view of the thread guide, oriented according to line 4 — 4 of FIG. 1, but omitting the elements of FIG. 4 that are not included in the guide.
FIG. 8 is a top view of the thread guide, oriented according to line 8 — 8 of FIG. 1 .
DETAILED DESCRIPTION
FIG. 1 shows a fragment of a sewing machine 10 having a needle 12 detachably mounted on a shaft 14 . The shaft, and thus the needle, is mounted vertically, for vertical reciprocation as in known sewing machines. Hereinafter, the sewing machine and the thread guide are described as oriented in FIG. 1, with the needle disposed vertically.
The sewing machine has another vertical shaft 16 on which is detachably mounted a presser foot 18 of known kind. This shaft is adjustable vertically between an upper inactive position in which the presser foot is raised, and a lower active position in which the presser foot engages the base 22 of the sewing machine, or any material being sewed. FIG. 2 shows this presser foot in top view, and it will be seen that it includes a pair of spaced prongs 20 disposed generally horizontally, with a space 21 therebetween. These prongs are not truly horizontal, since usually they are curved, but the shape and arrangement is such that they extend generally along the surface of the base 22 or bottom element of the sewing machine.
At the beginning of a stitching step, the operator adjusts the shaft 16 downwardly to position the presser foot in its lower, active position, and it remains in that position throughout a predetermined period of stitching. The needle 12 is arranged to extend through the space 21 of the presser foot. The operation of the needle and the presser foot does not require detailed description, and emphasis is placed on the construction of the thread guide itself, which is identified 24 . In the description next following, it will be seen that the device is applied directly to the presser foot and supported thereby.
Reference is made to FIGS. 3 and 4 showing the thread guide 24 in its entirety, which is in the form of an attachment, as described in detail hereinbelow. The device includes a main body 26 and a guide pin 28 . The main body includes a shank 30 and a pair of prongs 32 .
When the device 24 is fitted on the prongs of the presser foot, the shank 30 extends generally upwardly, but at an oblique angle, and the prongs 32 extend generally horizontally. This main body is of a one-piece, integral construction, the shank being flat and blade-like, and the prongs, while extending generally horizontally, have a vertical dimension or extension 34 (FIG. 4 ), with a space 36 between the prongs. These prongs are parallel, having longitudinal groves 38 , on the inner, or opposing, surfaces, the groves opening out through the free ends of the prongs.
The elements are so arranged, that the shank 30 , and the prongs 32 , lie in planes generally perpendicular to a line 40 about which the angle between the shank and the prongs is determined, thereby providing great strength in the appropriate direction for performing a secure guiding function when the device is applied to the sewing machine.
The 28 includes a central pin element 42 rigidly mounted on the shank 30 by suitable means indicated 44 . A roller 46 is rotatably fitted on the pin element 42 and rotates to accommodate the thread which is guided around this roller.
To apply the guide to the sewing machine, the prongs 32 on the guide are moved longitudinally, to the right, FIG. 1, onto the prongs 20 of the presser foot. The outer free ends of the prongs 20 fit into the groves 38 in the guide prongs 32 . The prongs 32 and the groves 38 , are so dimensioned that the prongs 20 fit in the groves with a high friction fit, for holding the device in place. The guide attachment is applied by merely pushing it onto the presser foot, and removed by simply pulling it off. The thread guide is supported substantially entirely by the presser foot, although as referred to again hereinbelow, the thread in the sewing machine incidentally works in that direction also.
As indicated above, the presser foot is generally horizontal, and thereby the prongs 32 are generally horizontal, although not necessarily exactly so. The needle 12 is on a vertical axis line 48 , and when it is reciprocated it passes through the space 21 in the presser foot, and thereby necessarily through the space 36 (FIG. 5) in the attachment. It will be observed that when the guide is applied, the pin is spaced horizontally a substantial distance from the needle, as shown by the spacing 49 in FIG. 1 .
FIG. 1 shows the sewing thread 50 , which is to be guided by the guide. This thread leads from a source indicated diagrammatically at 52 in a known manner in present sewing machines, and then it is wrapped over the pin 28 of the attachment, and specifically around the roller 46 . This thread may be wrapped completely around the pin to assure its not being accidentally lifted off of the pin. The thread then leads to the needle at 54 and is threaded therethrough in the usual manner.
For convenience in referring to the assemblage of the needle, presser foot and thread guide, the needle and presser foot are at an inner end, and the upper end of the thread guide (pin 28 ) at an outer end.
The two lengths 50 a , 50 b , of the thread 30 , at the pin 28 , are held out away from the needle (FIG. 1) and this prevents that portion of the thread from being tangled or snagged by the needle. As will be understood, the thread, as it is being fed in a sewing step, as oriented in FIG. 1, is pulled away from the needle, to the right, by the material being sewed at the bottom of FIG. 1, and thereby the upper and lower lengths 50 a , 50 b , are taut. This pulling action to the right, on the thread in the sewing step, pulls the thread in the same direction, and thereby pulls the guide in the same direction, so that the guide is prevented from being dislodged, which would be to the left.
For convenience, and particularly in interpreting the claims, the presser foot prongs may be referred to as first prongs, and the thread guide prongs 32 as second prongs. | A single-piece, integral article having spaced parallel, open end prongs frictionally fitted on the prongs of a conventional presser foot on a sewing machine. The article has a pin which, when the article is applied in place, is spaced horizontally from the needle in the sewing machine, and the sewing thread is wrapped around the pin and held from becoming entangled. | 3 |
CROSS REFERENCE TO RELATED APPLICATIONS
This is a continuation of patent application Ser. No. 508,553 filed on Sept. 23, 1974, now abandoned which is a continuation of Ser. No. 352,267 filed on Apr. 18, 1973, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to brake control systems, and more specifically to an improved vehicle brake control system.
2. Description of the Prior Art
U.S. Pat. No. 3,691,524 relates to a tire inflation monitoring system for monitoring the angular movement of the wheels of a vehicle. By counting the revolutions on each of the wheels and comparing the count with the count from another wheel, it is possible to determine whether or not each wheel has the same diameter. An indicating means is provided for signalling an occupant of the vehicle when a tire thereon is underinflated. A disadvantage of this prior art monitoring system is its lack of sensitivity which precludes its use for operating a meter or indicating differences in wheel revolutions during braking.
U.S. Pat. No. 2,522,139 relates to a frequency responsive system for comparing two alternating current frequencies and creating a third frequency in relation to the difference in the two frequencies to indicate the sense and magnitude of this difference. A disadvantage of this frequency responsive system is that the compared frequencies involved are high and the difference frequency low in relation thereto so that this system is not readily usable in a monitoring system of the type disclosed in U.S. Pat. No. 3,691,524.
U.S. Pat. No. 3,797,893 relates to a brake force control system for vehicles in which a sensor is coordinated with each wheel for detecting its rotational condition. The signals from the sensors actuate inlet and outlet valves when they exceed or drop below certain threshold values so that the brake pressure either increases, remains constant, or decreases. In vehicles with a high center of gravity and especially with a short wheel base, an additional logic circuit connection is provided which decreases the pressure at the front wheel brakes if a signal symbolizing the road traction of the rear wheels does not arrive within a certain time delay.
U.S. Pat. Nos. 3,260,555, 3,482,887 and 3,756,663 are exemplary of anti-skid brake systems having electrical means for sensing the rotational speed of individual wheels. An electrical signal is obtained as a result of a variation in the signal in relation to a predetermined characteristic. The signal is used to automatically operate means for controlling and releasing the braking force on any wheel or number of wheels revolving slower than a desired speed. Although the latter patents all operate satisfactorily for preventing the wheels of a vehicle to skid, none of them are capable, among other things, of determining the prebraking rotational speed ratio of a pair of wheels and by controlling the brake force applied to the wheels maintaining the braking rotational speed ratio substantially equal to the prebraking rotational speed ratio.
SUMMARY OF THE INVENTION
In accordance with the preferred embodiments of the invention, an improved method is disclosed for controlling the brakes of a vehicle. The apparatus for practicing the method broadly comprises means for detecting the speed of rotation of a pair of wheels in a prebraking mode of operation, and if the difference in speed exceeds a predetermined amount, actuating means for disabling the brakes of the pair of wheels. More specifically, the detecting means generates first and second pulses of energy for the pair of wheels respectively. A novel comparer and voltage control circuit is provided comprising first and second pulse frequency counters connected in opposed relation for receiving the first and second pulses respectively and generating a signal when both pulses energize a station of the circuit which is indicative of the prebraking rotational speed ratio of the first and second wheels. First and second brakes are provided on the first and second wheels respectively, and means including a valve control circuit for applying the brakes. If the braking rotational speed ratio changes from the prebraking rotational speed ratio, the comparer and voltage control circuit generates a different signal voltage level in response thereto. The valve control circuit for controlling the brake force applied to the brakes is responsive to the different signal voltage level for adjusting the brake force to make the braking rotational speed ratio substantially equal to the prebraking rotational speed ratio. An advantage of this brake control system is to provide more accurate and precise control of the braking and hence of the vehicle. In a more specific embodiment of the apparatus, means are provided for disabling the brakes if the prebraking or braking rotational speed ratio exceeds a predetermined value with a pendulum switch mechanism indicating the beginning of vehicle skid and spin. In addition, means can be provided for actuating a warning system such as operation of the lights and/or horn of the vehicle if the rotational speed ratio exceeds a predetermined value combined with a pendulum switch mechanism. In still another embodiment of the invention, a prebraking rotational speed ratio is determined for one of the front and one of the rear wheels of the vehicle. The voltage control circuit is modified to generate a signal voltage level that is indicative of a braking rotational speed ratio that is different from the actual braking rotational speed ratio of the front and rear wheels generated by an unmodified voltage control circuit. Accordingly, the valve control circuit responds to the different signal voltage level applying the brake harder on the rear wheel than on the front wheel. The advantage of this is to prevent the vehicle from dipping in front and raising in the rear when the brakes are suddenly applied, or from jack-knifing if the vehicle is a tractor-trailer.
The invention and these and other advantages will become more apparent from the detailed description of the preferred embodiments presented below.
BRIEF DESCRIPTION OF THE DRAWING
In the detailed description of the preferred embodiments of the invention presented below, reference is made to the accompanying drawings, in which:
FIG. 1 is a schematic diagram of one embodiment of the invention;
FIG. 2 is a fragmentary front elevational view of a wheel speed sensor for this invention;
FIG. 3 is a fragmentary, side elevational view of the sensor of FIG. 2;
FIG. 4 is a front elevational view of a pair of incators for use in this invention;
FIG. 5 is a schematic block diagram illustrating a system for disabling the front brakes and intermittently operating the rear lights and horn;
FIG. 6 is a schematic block diagram of another preferred embodiment of this invention;
FIG. 7 is an electrical circuit diagram of the comparer for determining the rotational speed ratio of a pair of wheels;
FIG. 8 is an electrical circuit diagram of the brake control system of this invention;
FIG. 9 is a segmental view similar to a portion of FIG. 8 showing a modified voltage control circuit for applying the rear brakes harder than the front brakes;
FIG. 10 is an enlarged view of the meter of FIG. 8;
FIG. 11 is a section view of a pendulum switch for use in this invention; and
FIG. 12 is a section view taken substantially along line 12--12 of FIG. 11.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Because brake control mechanisms for vehicles are well known, the present description will be directed to elements forming part of, or cooperating more directly with, an apparatus or method in accordance with the present invention. Vehicle or brake elements not specifically shown or described should be understood to be selectable from those known in the art.
With reference to FIG. 1, a preferred embodiment of an automobile apparatus and method is disclosed for indicating to the driver, during driving, differences in the speed of rotation of the wheels. Elements can be added to or subtracted from the illustrated system depending upon the sophistication desired.
Wheels speed sensors 10-13 are applied to each wheel "A" of the vehicle such as an automobile, and for a vehicle having more than four wheels, additional wheel speed sensors, not shown, are preferably added. Wheel speed sensors 10-13 each produce an electric pulse train having a frequency directly proportional to the rotational speed of the wheel of the vehicle, and there are several ways that sensors 10-13 can produce such pulse trains. Pneumatic, hydraulic, and optical wheel speed sensors can be used, but the preferred sensors 10-13 use an electromagnetic field in the region of each wheel, and an element rotating with each wheel and disposed to produce an electric pulse as a projection irregularity on the rotating element passes through the electromagnetic field. For example, as schematically shown in FIGS. 2 and 3, a mounting bracket 14 supports an electromagnetic coil 15 energized through wire 16 and disposed adjacent a rotating disc 17 having projection 18 passing near coil 15 as the wheel rotates. Disc 17 can be a disc brake rotating with the wheel, and as many projections 18 can be made as desired. Each time a projection 18 passes by coil 15, a pulse is produced so that the output pulse train is directly proportional to the rotation of the wheel. The frequency of the pulse train depends on the number of projections 18 on disc 17 and the speed of the wheel.
Pulse trains from wheel sensors 10-13 are preferably processed in generally known ways and fed to a frequency comparer or counter 20 of any suitable type known in the art which is programmed to make predetermined comparisons in the pulse trains. For example, a wheel speed difference between a pair of front wheels or between a pair of rear wheels is fairly dangerous and it can change the direction of the vehicle when the brakes ae applied. To produce an indication of any such difference, frequency comparer 20 compares the rotational speed of front wheels 12 and 13 and the rotational speed of rear wheels 10 and 11 and provides suitable outputs to indicator 21 for displaying the comparison results to the driver. Such a display could be digital, audible, warning lights, and other warnings or indications, and FIG. 4 shows a possible pair of indicators for such a display. Indicator 22 displays the front wheel rotational speed comparison by moving pointer 23 from the illustrated "0" position toward the fast turning wheel, and indicator 24 provides a similar indication by moving pointer 25 toward the faster one of the rear wheels. If pointers 23 or 25 move off center, the driver knows which wheel of the front pair or rear pair is rotating faster. He can then check for tire wear, underinflation of a tire, or faulty brakes, depending upon the circumstances.
The system illustrated in FIG. 1 has a frequency interval varier 27 that can be controlled through a driver selection input 28 or automatically when the brakes are applied through a brake application signal 29 derived from brake pedal 30. Frequency interval carier 27 provides a variable frequency count time interval when the vehicle is traveling in a prebraking mode of operation, and provides for a relatively instantaneous frequency comparison while the brakes are applied. Accordingly, while the vehicle is traveling, the driver can be informed of differences in wheel rotational speed measured over long or short intervals, or as long as the brakes are applied. Rotational variations are displayed to the driver on indicator 21. Lights 26 on instruments 22, 24, light whenever the brakes are applied to remind the driver that the indicated wheel comparison results are occurring during braking of the vehicle.
The results from frequency comparer 20 and any indication to the driver can also be recorded on recorder 31, if desired. Recorder 31 can be any of several known devices to produce a paper, magnetic, or other record of variations in wheel rotation. Recorder 31 is especially useful for severe braking tests where the driver has little time to observe instruments 22 and 24, and particularly in support of documentation of inspection.
With reference to FIG. 5, a brake control system is disclosed to support the driver to steer the vehicle in the event an extreme fault such as a blowout should occur. In this system, the front wheel indicator 22 is responsive to pulse trains generated by wheel sensors 12, 13 of the front wheels. Should a blowout occur on a front wheel, needle 23 will move rapidly from its normal full line position to a maximum position to the right or left as illustrated by a dotted arrow. The force activating needle 23 and generated by a predetermined pulse difference in counters 20 actuates a solenoid 60 through any suitable mechanism for closing a valve 62 in the main brake power or feeder line preventing the application of fluid pressure to the cylinders of the front wheel brakes 64. Accordingly, the front wheel brakes are disabled, and will remain in this condition until reset. The solenoid 60 also instantaneously activates one or more switches 66 for controlling any suitable electrical make-and-break circuits 68, 70 connected to the rear lights and horn respectively. Consequently, so long as the extreme fault occurs, the front brake systems 64 are disabled, and the rear lights and horn are intermittently operated, Although the brake control system of FIG. 5 is illustrated in relation to a pair of front wheels, such system is clearly applicable to any pair of corresponding wheels.
With reference to FIG. 6, a schematic block diagram is disclosed of a vehicle brake control system for determining the prebraking rotational speed ratio of a pair of wheels. The brake control system then controls the brakes during braking to maintain a braking rotational speed ratio substantially equal to the prebraking rotational speed ratio. In this system, a pair of front wheel sensors E 1 , E 2 , and a pair of rear wheel sensors E 3 , E 4 are provided. The output of the front wheel sensors is fed into a novel frequency comparer and electronic voltage control circuit C 1 as shown in FIG. 8, and the output from the rear wheel sensor is fed into a similar frequency comparer and voltage control circuit C 2 . The signal outputs of the comparers are supplied to the electronic voltage control circuits and the voltage outputs from the voltage control circuits are fed to dashboard meters M 1 , M 2 and wheel brake valves V 1 , V 2 , V 3 , and V 4 . The comparers and voltage control circuits C 1 , C 2 determine the prebraking rotational speed ratios of the front and rear wheels respectively and further generate potentials in the voltage control circuit which are fed to the brake valve control circuit during the braking mode of operation of the vehicle. The brake valve control circuit controls the brakes to make the braking rotational speed ratio of the wheels substantially equal to the prebraking rotational speed ratio of the wheels. The advantage of this is to give the driver better control of the vehicle during braking and to greatly minimize the likelihood of one wheel skidding during braking which might tend to cause the vehicle to veer or sway.
With reference to FIGS. 7 and 8, a preferred embodiment of only the frequency comparer and voltage control circuit C 1 is disclosed, since the control circuits C 1 and C 2 (FIG. 6) are substantially identical. A pair of counters G 1 , G 2 are provided, each having nine counting stations for purposes of illustration, although any suitable number may be used. In addition, two "out-of-control" stations 0 to 10 are provided. The larger the number of stations used the more accurate and precise will be the braking action. The counters G 1 , G 2 are arranged in opposed relation so that the pulses from sensors E 1 , E 2 will enter from opposite ends of the counters. Each station 1-9 has a pair of flip-flops of known type responsive to the pulses entering the counters. Accordingly, as the pulses from sensor E 1 , proceed through counter G 1 from the left to the right, the pulses from sensor E 2 proceed through counter G 2 from the right to the left. As the pulses proceed through the counters G 1 , G 2 nothing happens as long as only one flip-flop of each station 1-9 is energized. However, when the oppositely directed pulses simultaneously trigger both flip-flops in one station, and an AND gate AG connected thereto, one for each station 1-9, is triggered for supplying a reset pulse to the counters G 1 , G 2 for resetting the counters and transistors TA, one for each station 1-9 and of which only TA 3 , TA 4 and TA 5 are shown for purposes of clarity, and for supplying a pulse to a silicon controlled rectifier WA in the voltage control circuit, of which only WA 3 , WA 4 and WA 5 are illustrated. Since transistor TA of each station 1-9 normally conducts, the active voltage from the voltage divider network of any known type such as resistors, not shown, connected in series is supplied to one lead of the meter M 1 and to one lead of a pair of amplifiers A in the brake valve control circuit. The amplifiers A are connected to the brake valves V through a switch S 2-2 which is closed during the braking modes of operation, such as by depression of the brake pedal.
When the vehicle brake pedal is in its normal retracted position, a pulse circuit S 4-2 of any suitable type (FIG. 8) is energized for as long as the brake pedal is retracted for feeding a pulse through a diode D5 to a silicon controlled rectifier WR5. A rectifier WR is provided for each station 1-9 of which only WR 3 , WR 4 and WR 5 are shown. WR5 conducts through normally conducting transistor TR5 for supplying a reference voltage of 5 volts from the voltage divider network to another lead of the meter M 1 and another lead of the pair of amplifiers A. The meter reading resulting from the active and reference voltages designates the prebraking rotational speed ratio of a pair of wheels. Assuming for the moment that both wheels are rotating at the same speed, the flip-flops at station 5 would both be actuated for feeding an active voltage of 5 volts to the meter. Since the reference voltage supplied through the pulse S 4-2 is also 5 volts, the meter needle would be in a vertical position including a prebraking rotational speed ratio of 1 to 1.
Let us now assume that one wheel is rotating at a different speed than the other and that as a consequence of this the flip-flops 3 and 7 at station 3 are actuated. Accordingly, the corresponding AND gate AG3 would be energized for energizing the silicon controlled rectifier WA3 for feeding a voltage of 3 volts to the meter M 1 as the active voltage. Since the reference voltage through the pulse circuit S 4-2 is still 5 volts (silicon controlled rectifier WR5 still conducting), the meter needle would move to the left with reference to meter M 1 (FIG. 10) indicating a prebraking rotational speed ratio between the wheels of approximately 2.5 which is the ratio of the pulses at station 3. It should be understood that the values indicated are illustrative only and that the actual values would probably vary. Accordingly, as long as the vehicle is operated with the brake pedal in the "up" position, the meter will indicate the prebraking rotational speed ratio of the wheels. Since the prebraking rotational speed ratio is dependent upon such factors such as tire inflation and tire wear, such ratio will remain relatively constant during driving for any pair of wheels over a long period of time.
Let us assume now that the prebraking rotational speed ratio is approximately 2.5 and the driver depresses or applies the brake pedal. This results in the generation of a pulse by pulse circuit S 3-1 which energizes a silicon controlled rectifier WB for applying a potential to all of the K gates in the counter stages and all transistors (TR1-10) momentarily cutting off the current flow through the transistors. Since AND gate AG3 is the only AND gate operating (due to the aforementioned triggered flip-flops 3 and 7) the K3 AND gate is energized for feeding a reset pulse through transistor TB cutting off the potential to the K gates. The AND gate K3 which continues to operate due to its prior energization also feeds a pulse to silicon controlled rectifier WR3 which conducts through normally conducting transistor TR3 to feed a reference voltage of 3 volts to the meter. Since the active voltage fed through flip-flops 3 and 7 and silicon controlled rectifier WA3 is also 3 volts, the meter needle will return to the vertical position indicating a ratio of 1. The amplifiers and the brake valve circuit are accordingly not subjected to any difference in potential and hence will not affect the operation of the brake valve. Assume however, that as the braking action proceeds, the braking rotational speed ratio of the wheels begins to change and that flip-flops 4 and 6 at station 4 are now actuated resulting in a braking rotational speed ratio of 1.5. Flip-flops 4 and 6 energize AND gate AG4 resulting in an active voltage of 4 volts applied to the brake amplifiers. However, AND gate K 4 at station 4 will not operate since the voltage to the K gates has been cut off previously by transistor TB. Silicon controlled rectifier WR3 continues to operate and continues to feed a reference voltage of 3 volts to the amplifiers. Accordingly, the amplifiers are now subjected to a voltage difference of 1 volt which controls the brake valves by reducing the braking force on the harder braking wheel in an effort to return the braking rotational speed ratio of 1.5 back to the prebraking speed ratio of about 2.5 and the needle back to its vertical position.
If a blowout or the like should occur before braking causing a rapid change in the rotational speed ratio of a pair of wheels and a resulting ratio which is off the limits of the comparer, the voltage control circuit would not be able to function. Accordingly, one of the flip-flops at station 0 or 10 would be energized resulting in a pulse fed to AND gate K 0 or K 10 respectively which coupled with signals applied to the AND gate from pendulums P 1 and P 2 caused by the vehicle skidding and spinning applies a potential to the amplifiers A which would release the brake valves causing the brakes to be completely disabled on the affected pair of wheels. If no signals are applied by pendulums P 1 and P 2 , the front brakes are not disabled and as soon as the rotational speed ratio returns within the limits of the comparer, brake valve control is automatically implemented in the brake mode, and in the prebraking mode the brakes are again operative.
In order to prevent, for example, the front end of the vehicle from dipping and the rear end raising during the braking operation, and to prevent the trailer from pushing the tractor in brake mode (jack-knifing), it is desirable to apply the rear brakes a little harder than the front brakes so that the braking action on the rear brakes is greater than on the front brakes. This is achieved in this invention by providing a frequency comparer and voltage control circuit C 3 (FIG. 6) for comparing the rotational speed ratio of any one of the front wheels with any one of the rear wheels. The control circuit is slightly modified as indicated in FIG. 9 so that the K gate at each station is connected to the voltage control circuit of the previous station. Accordingly, when the brake is applied as described heretofore instead of no voltage difference being applied to the amplifiers A (assuming the braking and prebraking rotational speed ratios are equal), a voltage difference is applied which actuates brake valve V 5 (FIG. 6) which in turn controls the wheel brake valves V 1 and V 2 causing the rear brakes to brake harder than the front brakes. This would also occur for subsequent action during braking in which the rotational speed ratio changes. In the previous example, operation of the flip-flops at station 4 of counters G 1 or G.sub. 2 (FIG. 7) caused a voltage difference of 1 volt to be applied to the amplifiers for controlling the brake valves. However, with comparer and voltage control circuit C 3 modified (FIG. 9), a voltage difference of 2 volts would be applied to the amplifiers of the brake valve control circuit causing the rear brakes to brake harder than the front brakes.
With reference to FIGS. 6, 11 and 12, a mechanical system is disclosed for use in conjunction with the frequency comparer FIG. 4 and control circuit FIG. 8 for disabling the front brakes of a two axle vehicle such as a car or all of the tractor wheels of a tractor-trailer vehicle in those instances in which the vehicle goes into a skid and spin. In this situation, switches O 1-5 actuated by the pendulums P 1 , P 2 feed a voltage to the gates K 0 , K 10 in combination with the counters G 1 , G 2 (FIG. 7) and to the control circuit (FIG. 8) for disabling the brakes for a time interval determined by timers, T2 (FIG. 6). In addition, a warning device of any suitable type such as the horn or intermittent operation of the rear brake lights may also be activated.
The pendulums P 1 , P 2 each comprise a cylindrical member 20 having closed ends 22 for rigidly supporting an axial shaft 24. A ball 26 is slideably mounted on shaft 24 within cylinder 20 and is held in a normal central position by a pair of springs 28 of equal strength interposed between the cylinder ends 22 and discs 30 bearing against the ball. The ball has a notch 32 within which one end of a depressable switch actuator 34 is recessed. The switch actuator 34 is slideably mounted within an elongated axially extending slot 36 in the cylinder, and the opposite end of the actuator cooperates with a plurality of switches O 1-5 . Although only five switches are illustrated schematically, any number of such switches can be used. The pendulums P 1 , P 2 are preferably mounted in the rear of a vehicle with one arranged parallel to the vehicle axis and the other arranged at right angles thereto as illustrated schematically in FIG. 6. Accordingly, during normal operation of the vehicle, the balls of pendulums P 1 , P 2 will assume the central positions actuating switches O 3 for indicating via a dash light that the pendulums are operative, i.e., no broken springs or the like. Also in this position the brake valves will be unaffected. However, should the vehicle spin, the centrifugal and inertial forces will cause the balls 26 to slide along the shafts actuating the switches. If switches O 2 or O 4 are actuated by pendulums P 1 and P 2 a signal will be fed to AND gate K 0 or K 10 . If a signal is also supplied by a comparer and voltage control circuit C 1 or C 2 , the front brakes will be disabled. If the spin is more severe causing switches O 1 or O 5 to be actuated, brake valves V 1-5 are actuated directly to disable the front brakes.
In the situation where the vehicle is travelling at high speed and the brakes applied hard, it is desirable to ease the extreme stress to which the brake material is subjected. This is accomplished by the operation of pendulum P 1 (FIG. 6) only since pendulum P 2 is inactive unless the vehicle is spinning. During such hard braking, the ball is pendulum P 1 will oscillate back and forth automatically causing switches similar to switches O 1-5 to intermittently disable the brakes resulting in an automatic brake pumping action. For better control of the braking intervals, a timer T 1 (FIG. 6) can be electrically coupled to the switches rather than relying solely on the mechanical properties of the pendulum P 1 .
The invention has been described in detail with particular reference to preferred embodiments, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention as described. | A brake control system for vehicles in which the difference in speed of rotation of a corresponding pair of wheels is detected in a prebraking mode of operation. If the difference in rotational speed exceeds a predetermined amount, the brakes on the pair of wheels are disabled. In one embodiment of the invention, the prebraking rotational speed ratio of the pair of wheels is determined by a comparator and electronic voltage control circuit, and the electrical output thereof fed to a valve control circuit for controlling the brake valves to maintain the braking rotational speed ratio of the wheels substantially equal to the prebraking rotational speed ratio. In the event the control circuits are unable to maintain the braking rotational speed ratio substantially equal to the prebraking rotational speed ratio, and such ratio exceeds a predetermined value, and a pendulum switch mechanism combined therewith indicates the beginning of a vehicle skid and spin, the brakes will be automatically disabled on both wheels. The disablement of the brakes is caused by a pair of pendulum switch mechanisms in combination with the control circuit. | 1 |
RELATED APPLICATION
Copending U.S. patent application Ser. No. 784,888, filed Apr. 5, 1977, now U.S. Pat. No. 4,101,723, issued July 18, 1978, by Hauck, Fox and Watrous discloses substituted piperazinopropanol hypotensive agents having the formula ##STR3## wherein R 1 is alkanoyl; R is aryl or pyridinyl; and n is 0, 1 or 2.
BACKGROUND OF THE INVENTION
Cyclitol derivatives having the formula ##STR4## wherein Y is hydrogen or alkanoyl, the group -NXX' is a heterocyclic nitrogen containing group, and n is 0, 1 or 2 are encompassed by the disclosure of U.S. Pat. No. 3,894,031, issued July 8, 1975. Among the heterocyclic groups disclosed are piperidino, (lower alkyl)piperidino, di(lower alkyl) piperidino, (lower alkoxy)piperidino, aminomethylpiperidino, piperazino, (lower alkyl)piperazino, di(lower alkyl)piperazino, (lower alkoxy)piperazino, (hydroxy-lower alkyl)piperazino, (alkanoyloxy-lower alkyl)piperazino, (hydroxy-lower alkoxy-lower alkyl)piperazino, and (carbo-lower alkoxy)piperazino. The treatment of hypertension is one of the utilities for the compounds disclosed by the patent.
Burger, Medicinal Chemistry, third edition (part II), John Wiley & Sons, Inc., New York, 1970, chapter 39, "Antihypertensive Agents", pgs. 1019-1064 discloses various classes of antihypertensive agents. Among the classes of compounds disclosed are veratrum alkaloids, the hypotensive activity of which may be largely attributable to the acylation of several hydroxyl functions of an alkamine. Other classes of antihypertensive agents disclosed by Burger include phenoxypropanolamines and phenethanolamines.
BRIEF DESCRIPTION OF THE INVENTION
Compounds having the formula ##STR5## and the pharmaceutically acceptable salts thereof, have hypotensive activity. In formula I, and throughout the specification, the symbols are as defined below.
n is 0, 1 or 2;
R 1 is alkanoyl (acetyl is preferred);
R 2 is ##STR6##
The term "alkanoyl", as used throughout the specification, refers to groups having the formula ##STR7## wherein Y is alkyl having 1 to 6 carbon atoms.
DETAILED DESCRIPTION OF THE INVENTION
The substituted 3,6-dihydro-1(2H)-pyridinylpropanols of this invention can be prepared by reacting an oxirane compound having the formula ##STR8## with a compound having the formula
R.sub.2 --H. III
reaction conditions are not critical, but the reaction proceeds more rapidly when carried out with heating in an organic solvent, or mixture of organic solvents, e.g., a lower alkanol such as ethanol, or an aromatic hydrocarbon such as benzene in combination with a lower alkanol.
The oxirane compounds of formula II are readily obtained from a corresponding compound having the formula ##STR9## Compounds of formula IV are known; see, for example, U.S. Pat. No. 3,894,031, issued July 8, 1975. Oxidation of a compound of formula IV yields the corresponding N-oxide having the formula ##STR10## Exemplary of oxidizing agents which may be used are the peracids, e.g., m-chloroperbenzoic acid.
Vacuum pyrolysis of an N-oxide of formula V yields an olefin having the formula ##STR11## Oxidation of an olefin of formula VI yields the corresponding oxirane compound of formula II. Exemplary of oxidizing agents which may be used are the peracids, e.g., m-chloroperbenzoic acid.
The tetrahydropyridinyl derivatives of formula II are either known in the art, or can be prepared as described in the examples of this specification.
The compounds of formula I can be converted to their pharmaceutically acceptable acid-addition salts with both organic and inorganic acids using methods well known in the art. Exemplary salts are hydrohalides (e.g., hydrochloride and hydrobromide), nitrate, phosphate, borate, acetate, tartrate, methanesulfonate, benzenesulfonate, toluenesulfonate and the like.
Formula I includes all stereoisomers and mixtures thereof. Particular stereoisomers are prepared by utilizing as the starting material the compound of formula IV with the corresponding stereochemistry. The preferred stereoisomers are those in which the OR 1 groups are all axial. Particularly preferred are those compounds having the configuration ##STR12## wherein the OR 1a and OR 1c groups are in the trans configuration as are the OR 1b and OR 1d groups.
The compounds of formula I show hypotensive properties in hypertensive rats and normotensive dogs. The compounds of this invention, and the pharmaceutically acceptable salts thereof, are useful as hypotensive agents in mammals, e.g., domestic animals such as dogs and cats. Daily doses of from 5 to 50 milligrams per kilogram of animal body weight, preferably about 5 to 25 milligrams per kilogram of animal body weight, can be administered orally or parenterally, in single or divided doses.
The compounds of this invention include indan derivatives having the formula ##STR13## naphthalene derivatives having the formula ##STR14## and benzocycloheptane derivatives having the formula ##STR15## The naphthalene derivatives of formula IX are preferred.
The following examples are specific embodiments of this invention.
EXAMPLE 1
3,4a,5-cis-5-[3-(3,6-Dihydro-4-phenyl-1(2H)-pyridinyl)-2-hydroxypropyl]-decahydro-2,3;4a,8a-trans-naphthalenetetrol, tetraacetate ester
A solution of 2.5 g of 3,4a,5-cis-decahydro-5-(oxiranylmethyl)-2,3;4a,8a-trans-naphthalenetetrol, tetraacetate ester (see copending U.S. patent application Ser. No. 784,888, filed Apr. 5, 1977) and 0.86 g of 4-phenyl-1,2,3,6-tetrahydropyridine is 20 ml benzene-50 ml absolute ethanol is stirred at 55°-57° C. for about 16 hours under a drying tube. The solution is evaporated in vacuo and the residue is crystallized from 30 ml of 1:2 ethyl acetate-ether to give 0.85 g of solid. A second crop yields 0.35 g of solid. Recrystallization from 2:1 ethyl acetate-ether yields 1.1 g of the title compound, melting point 193°-199° C.
EXAMPLE 2
Decahydro-5-[2-hydroxy-3-(1,4,5,6-tetrahydrobenz[f]isoquinolin-3(2H)-yl)propyl]-3,4a,5-cis-2,3;4a,8a-trans-naphthalenetetrol, tetraacetate ester
1,2,3,4,5,6-Hexahydrobenz[f]isoquinoline, monohydrochloride (1.0 g) is dissolved in 20 ml of water, layered over with ether and neutralized with aqueous ammonia. The organic phase is removed and the aqueous phase is reextracted with ether (two 20 ml portions). Organics are combined, dried, filtered and stripped in vacuo to yield 0.75 g of the free base, which is dissolved in 20 ml of benzene and 50 ml of absolute ethanol. 3,4a,5-cis-Decahydro-5-(oxiranylmethyl)-2,3;4a,8a-trans-naphthalenetetrol, tetraacetate ester (1.813 g) is added to the solution, and the resulting solution is heated to 50° C.±5° for 18 hours. Solvent is removed in vacuo, the residue is taken up in ether and the resulting powder is recrystallized from ethyl acetate to yield 1.17 g of the title compound.
EXAMPLE 3
3,4a,5-cis-Decahydro-5-[2-hydroxy-3-[4-(2-phenylethenyl)-3,6-dihydro-1(2H)-pyridinyl]propyl]-2,3;4a,8a-trans-naphthalenetetrol, tetraacetate ester
(A) 1,2,3,6-Tetrahydro-4-(2-phenylethenyl)-1-(phenylmethyl)pyridine, monohydrochloride
N-Benzylstyrylpyridinium bromide (59.0 g) is reduced by stirring in 750 ml of 50% aqueous methanol to which 30 g of sodium borohydride is added portionwise. Methanol is removed in vacuo, the resulting slurry is filtered and the solids are partitioned between water and chloroform. The aqueous layer is re-extracted with chloroform. The chloroform extracts are combined, washed with aqueous sodium chloride, dried and stripped to yield 33.2 g of the title compound. Four grams of this product is dissolved in absolute ethanol, acidified with anhydrous hydrogen chloride in isopropanol, yielding 3.7 g of solid, which is recrystallized from methanol-isopropanol to yield 2.72 g of crystals, melting point 235°-240° C.
(B) 1,2,3,6-Tetrahydro-4-(2-phenylethenyl)pyridine
A solution of 46 g 1,2,3,6-tetrahydro-4-(2-phenethenyl)-1-(phenylmethyl)pyridine in 150 ml of toluene is treated with 30.1 g of phenyl chloroformate and heated at reflux for 12 hours. Solvent is removed in vacuo to yield 62.7 g of a solid. The above solid is heated to 130° C. with the aid of an oil bath and 50 g of powdered potassium hydroxide is added, portionwise. Heating is continued for 90 minutes, the mixture is cooled, taken up in 200 ml water and extracted with chloroform. Organics are combined, washed with aqueous sodium chloride, dried, filtered and stripped to yield 43 g of an oil which is taken up in ether, filtered and stripped to yield 33 g of oil. Twenty-eight grams of the oil is refluxed in 1 liter of hexane, the solvent is decanted from the oil, the oil is cooled to room temperature, filtered, then cooled in an ice box to yield a crystalline product. Due to the poor differential solubility, this process is repeated about eight times, yielding a total of 1.05 g of the free base.
(C) 3,4a,5-cis-Decahydro-5-[2-hydroxy-3-[4-(2-phenylethenyl)-3,6-dihydro-1(2H)-pyridinyl]propyl]-2,3;4a,8a-trans-naphthalenetetrol, tetraacetate ester
1,2,3,6-Tetrahydro-4-(2-phenylethenyl)pyridine (1.04 g) and 2.5 g of 3,4a,5-cis-decahydro-5-(oxiranylmethyl)-2,3;4a,8a-trans-naphthalenetetrol, tetraacetate ester are dissolved in 50 ml of absolute ethanol and 20 ml of benzene, and heated at 55° C.±5° for 15 hours. Solvent is evaporated in vacuo and the resulting gum crystallized from ether. Solids are collected yielding 1.35 g of brown solid which is taken up in ethyl acetate, decolorized with activated charcoal, filtered, hexane added and left standing. Resulting solids are collected and dried to yield 1.0 g of powder, melting point 183°-185° C.
EXAMPLE 4
3,4a,5-cis-5-[3-[4-(2,3-Dihydro-2-benzoxazolyl)-3,6-dihydro-1(2H)-pyridinyl]-2-hydroxypropyl]-decahydro-2,3;4a,8a-trans-naphthalenetetrol, tetraacetate ester
(A) 2-(4-Pyridinyl)benzoxazole
A mixture of 2-aminophenol (10.9 g), isonicotinic acid (12.3 g) and polyphosphoric acid (250 g) is heated under a nitrogen atmosphere at 210° C. for 3 hours. The mixture is then cooled to 160° C. and slowly poured into 1 liter of water. The mixture is cooled by adding ice and neutralized with 50% sodium hydroxide solution yielding 16.2 g of crude product. Crystallization from hexane yields 14.8 g of the title compound, melting point 129°-131° C.
(B) 4-(2-Benzoxazolyl)-1-(phenylmethyl)pyridinium chloride
A solution of 117.0 g of 2-(4-pyridinyl)benzoxazole and 95.0 g of benzyl chloride in 1 liter of a 9:1 mixture of n-propanol and dimethylsulfoxide is heated at reflux for 72 hours. The solvent mixture is then removed and the residue suspended in 100 ml of water. The crystalline product which separates is filtered, washed with acetone, and dried to give 76.6 g of product. Concentration of the mother liquors gives an additional 27.8 g of product, melting point 194°-196° C., dec. Recrystallization from water and drying in a vacuum at 100° C. for 5 hours raises the melting point to 216°-217° C., dec.
(C) 2-(1-Benzyl-1,2,3,6-tetrahydro-4-pyridinyl)benzoxazole
To a stirred solution of 16.6 g of 4-(2-benzoxazolyl)-1-(phenylmethyl)pyridinium chloride in 1 liter of a 1:1 mixture of alcohol and water is added a solution of 2.84 g of sodium borohydride at a rate that maintains the temperature of the mixture at 30°-35° C. The reaction mixture is acidified with hydrochloric acid, concentrated to one-half volume and the crystals filtered to give 8.7 g of the hydrochloride salt of the title compound, melting point 227°-228° C., dec.
The mother liquors are made alkaline with solid sodium bicarbonate, extracted with chloroform and the extract concentrated to give a gummy residue. Recrystallization of this material from absolute alcohol gives 2.1 g of the title compound, melting point 129°-130° C.
(D) 4-(2-Benzoxazolyl)-3,6-dihydro-1(2H)-pyridinecarboxylic acid, 2,2,2-trichloroethyl ester
To a vigorously stirred solution of 109.1 g of 2-(1-benzyl-1,2,3,6-tetrahydro-4-pyridinyl)benzoxazole in 1 liter of dry toluene is added dropwise 96.4 g of 2,2,2-trichloroethyl chloroformate during 2 hours and the mixture is heated at reflux for 1.5 hours. The reaction mixture is then cooled, extracted with 250 ml of cold 10% hydrochloric acid, with 250 ml of cold 10% aqueous sodium hydroxide solution, and with an equal volume of water, dried (anhydrous magnesium sulfate), and concentrated. The oily residue is then further concentrated from an oil bath maintained at 50° C. under a vacuum of 0.2 mm of Hg to remove the remaining benzyl chloride.
The viscous oil is dissolved in 500 ml of boiling absolute ethanol and cooled to give, after filtration and drying, 56.9 g of crystalline product, melting point 134°-135° C. The mother liquors give, after concentration to one-half volume and cooling an additional 11.0 g of product identical with that above.
(E) 2-(1,2,3,6-Tetrahydro-4-pyridinyl)benzoxazole
To a solution of 52.6 g of 4-(2-benzoxazolyl)-3,6-dihydro-1(2H)-pyridinecarboxylic acid, 2,2,2-trichloroethyl ester in 1250 ml of glacial acetic acid is gradually added 92.5 g of zinc dust and the reaction mixture stirred at room temperature under nitrogen for 6 hours. The reaction mixture is filtered and concentrated on the rotary evaporator to give a viscous gum. This material is suspended in 500 ml of water, the pH adjusted to 2-3, and the suspension extracted with 500 ml of ether in two portions. These are combined, dried and concentrated to give 11.32 g of unreacted starting material.
The separated turbid, aqueous phase is filtered, cooled, made strongly alkaline, and extracted three times with 250 ml portions of chloroform. The combined extracts are dried and concentrated to give 6.0 g of crystals, melting point 136°-138° C.
(F) 3,4a,5-cis-5-[3-[4-(2,3-Dihydro-2-benzoxazolyl)-3,6-dihydro-1(2H)-pyridinyl]-2-hydroxypropyl]-decahydro-2,3;4a,8a-trans-naphthalenetetrol, tetraacetate ester
Three grams of 3,4a,5-cis-decahydro-5-(oxiranylmethyl)-2,3;4a,8a-trans-naphthalenetetrol, tetraacetate ester is dissolved in 50 ml of absolute ethanol and 20 ml of benzene. To this is added 1.34 g of 2-(1,2,3,6-tetrahydro-4-pyridinyl)benzoxazole and the resulting solution is heated to 55° C.±5° for 16 hours. Solvent is stripped in vacuo and the resulting gum is taken up in ether. The ether solution is filtered, diluted with hexane and left standing. Solids are collected to yield 3 g of solid which is recrystallized from ethyl acetate and hexane to yield 1.6 g of the title compound, melting point 204°-210° C., dec.
EXAMPLE 5
3,4a,5-cis-Decahydro-5-[2-hydroxy-3-(1,2,3,4-tetrahydro-2-isoquinolinyl)propyl]-2,3;4a,8a-trans-naphthalenetetrol, tetraacetate ester
A solution of 3.0 g of 3,4a,5-cis-decahydro-5-(oxiranylmethyl)-2,3;4a,8a-trans-naphthalenetetrol, tetraacetate ester and 0.94 g of 1,2,3,4-tetrahydroisoquinoline in ethanol-benzene (50:20) is warmed in a 55° C. bath for about 16 hours. The solution is evaporated in vacuo to give 4 g of solid. Two recrystallizations from ethyl acetate/ether/hexane yield 1.9 g of the title compound, melting point 185°-195° C.
EXAMPLE 6
3,4a,5-cis-Decahydro-5-[2-hydroxy-3-(4,5,6,7-tetrahydro-1H-imidazo[4,5-c]pyridin-5-yl)propyl]-2,3;4a,8a-trans-naphthalenetetrol
To a solution of 0.55 g of sodium hydroxide in 30 ml of absolute ethanol is added 1.35 g of 4,5,6,7-tetrahydro-1H-imidazo[4,5-c]pyridine, hydrochloride. After stirring for about 5 minutes a solution of 3.0 g of 3,4a,5-cis-decahydro-5-(oxiranylmethyl)-2,3;4a,8a-trans-naphthalenetetrol, tetraacetate ester in 30:50 ethanol:benzene is added and the solution is stirred for about 16 hours at 40°-45° C. The mixture is filtered and the filtrate is evaporated in vacuo to give 3.8 g of foam. The foam is dissolved in 50:20 ethanol:benzene and stirred for 24 hours at 55°-58° C. The solvent is removed in vacuo and the residue is dissolved in ethyl acetate, heated with activated charcoal and filtered. After diluting with a small amount of ether and storing at -15° C. for 3 days, 1.3 g of solid is obtained. Recrystallization from ethyl acetate (trace methanol) yields 1.0 g of the title compound, melting point 214°-216° C.
EXAMPLES 7-8
Following the procedure of Example 1, but substituting the compound listed in column I for 3,4a,5-cis-decahydro-5-(oxiranylmethyl)-2,3;4a,8a-trans-naphthalenetetrol, tetraacetate ester, yields the compound listed in column II.
______________________________________ Column I Column II______________________________________3a,5-cis-3a,7a;5,6-trans- 3a,5-cis-3a,7a;5,6-trans-hexahydro-1-(oxiranylmethyl)- hexahydro-1-[3-(3,6-dihydro-1H-indene-3a,5,6,7a-tetrol, 4-phenyl-1(2H)-pyridinyl)-tetraacetate ester (see 2-hydroxypropyl]-1H-indene-United States patent appli- 3a,5,6,7a-tetrol, tetra-cation serial no. 784,888, acetate esterfiled April 5, 1977)3,4a,5-cis-hexahydro-5- 3,4a-cis-hexahydro-5-[3-(oxiranylmethyl)-2,3;4a,9a- (3,6-dihydro-4-phenyl-1(2H)-trans-benzocycloheptanetetrol- pyridinyl)-2-hydroxypropyl]-tetraacetate ester (see 2,3;4a,9a-trans-benzocyclo-United States patent appli- heptanetetrol, tetraacetatecation serial no. 784,888, esterfiled April 5, 1977)______________________________________
EXAMPLES 9-10
Following the procedure of Example 2, but substituting the compound listed in column I for 3,4a,5-cis-decahydro-5-(oxiranylmethyl)-2,3;4a,8a-trans-naphthalenetetrol, tetraacetate ester, yields the compound listed in column II.
______________________________________ Column I Column II______________________________________3a,5-cis-3a,7a;5,6-trans- 3a,5-cis-3a,7a;5,6-trans-hexahydro-1-(oxiranylmethyl)- hexahydro-1-[2-hydroxy-3-1H-indene, 3a,5,6,7a-tetrol, (1,4,5,6-tetrahydrobenz[f]-tetraacetate ester isoquinolin-3(2H)-yl)propyl]- 1H-indene-3a,5,6,7a-tetrol, tetraacetate ester3,4a,5-cis-hexahydro-5- 3,4a-cis-hexahydro-5-[2-(oxiranylmethyl)-2,3;4a,9a- hydroxy-3-(1,4,5,6-tetra-trans-benzocycloheptane- hydrobenz[f]isoquinolin-tetrol, tetraacetate ester 3(2H)-yl)propyl]-2,3;4a,9a- trans-benzocycloheptanetetrol, tetraacetate ester______________________________________
EXAMPLES 11-12
Following the procedure of Example 3, but substituting the compound listed in column I for 3,4a,5-cis-decahydro-5-(oxiranylmethyl)-2,3;4a,8a-trans-naphthalenetetrol, tetraacetate ester, yields the compound listed in column II.
______________________________________ Column I Column II______________________________________3a,5-cis-3a,7a;5,6-trans- 3a,5-cis-3a,7a;5,6-trans-hexahydro-1-(oxiranylmethyl)- hexahydro-1-[2-hydroxy-3-1H-indene-3a,5,6,7a-tetrol, [4-(1-phenylethenyl)-3,6-tetraacetate ester dihydro-1(2H)-pyridinyl]- propyl]-1H-indene-3a,5,6,- 7a-tetrol, tetraacetate ester3,4a,5-cis-hexahydro-5- 3,4a-cis-hexahydro-5-[2-(oxiranylmethyl)-2,3;4a,9a- hydroxy-3-[4-(1-phenyl-trans-benzocycloheptane- ethenyl)-3,6-dihydro-tetrol, tetraacetate ester 1(2H)-pyridinyl]propyl]- 2,3;4a,9a-trans-benzocyclo- heptanetetrol, tetra- acetate ester______________________________________
EXAMPLES 13-14
Following the procedure of Example 4, but substituting the compound listed in column I for 3,4a,5-cis-decahydro-5-(oxiranylmethyl)-2,3;4a,8a-trans-naphthalenetetrol, tetraacetate ester, yields the compound listed in column II.
______________________________________ Column I Column II______________________________________3a,5-cis-3a,7a;5,6-trans- 3a,5-cis-3a,7a;5,6-trans-hexahydro-1-(oxiranylmethyl)- hexahydro-1-[3-[4-(2,3-1H-indene-3a,5,6,7a-tetrol, dihydro-2-benzoxazolyl)-tetraacetate ester 3,6-dihydro-1(2H)-pyridinyl] 2-hydroxypropyl]-1H-indene- 3a,5,6,7a-tetrol, tetra- acetate ester3,4a,5-cis-hexahydro-5- 3,4a-cis-hexahydro-5-[3-[4-(oxiranylmethyl)-2,3;4a,9a- (2,3-dihydro-2-benzoxazolyl)trans-benzocycloheptane- 3,6-dihydro-1(2H)-pyridinyl]tetrol, tetraacetate ester 2-hydroxypropyl]-2,3;4a,9a- trans-benzocycloheptane- tetrol, tetraacetate ester______________________________________
EXAMPLES 15-16
Following the procedure of Example 5, but substituting the compound listed in column I for 3,4a,5-cis-decahydro-5-(oxiranylmethyl)-2,3;4a,8a-trans-naphthalenetetrol, tetraacetate ester, yields the compound listed in column II.
______________________________________ Column I Column II______________________________________3a,5-cis-3a,7a;5,6-trans- 3a,5-cis-3a,7a;5,6-trans-hexahydro-1-(oxiranylmethyl)- hexahydro-1-[2-hydroxy-3-1H-indene-3a,5,6,7a-tetrol, (1,2,3,4-tetrahydro-2-tetraacetate ester isoquinolinyl)propyl]-1H- indene-3a,5,6,7a-tetrol, tetraacetate ester3,4a,5-cis-hexahydro-5- 3,4a-cis-hexahydro-5-[2-(oxiranylmethyl)-2,3;4a,9a- hydroxy-3-(1,2,3,4-tetra-trans-benzocycloheptane- hydro-2-isoquinolinyl)-tetrol, tetraacetate ester propyl]-2,3;4a,9a-trans- benzocycloheptanetetrol, tetraacetate ester______________________________________
EXAMPLES 17-18
Following the procedure of Example 6, but substituting the compound listed in column I for 3,4a,5-cis-decahydro-5-(oxiranylmethyl)-2,3;4a,8a-trans-naphthalenetetrol, tetraacetate ester, yields the compound listed in column II.
______________________________________ Column I Column II______________________________________3a,5-cis-3a,7a;5,7-trans- 3a,5-cis-3a,7a;5,6-trans-hexahydro-1-(oxiranylmethyl)- hexahydro-1-[2-hydroxy-3-1H-indene-3a,5,6,7a-tetrol, (4,5,6,7-tetrahydro-1H-tetraacetate ester imidazo[4,5-c]pyridin-5- yl)propyl]-1H-indene-3a,- 5,6,7a-tetrol, tetra- acetate ester3,4a,5-cis-hexahydro-5-(oxi- 3,4a-cis-hexahydro-5-[2-ranylmethyl)-2,3;4a,9a-trans- hydroxy-3-(4,5,6,7-tetra-benzocycloheptanetetrol, hydro-1H-imidazo[4,5-c]-tetraacetate ester pyridin-5-yl)propyl]-2,3;- 4a,9a-trans-benzocyclo- heptanetetrol, tetra- acetate ester______________________________________ | Compounds having the formula ##STR1## and the pharmaceutically acceptable salts thereof, wherein R 1 is alkanoyl; R 2 is ##STR2## AND N IS 0, 1 OR 2; HAVE USEFUL HYPOTENSIVE PROPERTIES. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a non-provisional of and claims priority to U.S. Provisional Patent Application Ser. No. 61/444,747 filed Feb. 20, 2012 and titled “LIQUID DISPENSER”, which is herein incorporated in its entirety.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
Not Applicable.
APPENDIX
Not Applicable.
BACKGROUND OF THE INVENTION
The present invention relates to liquid dispensers, and particularly to liquid dispensers with manually actuated valves for controlling the flow of the liquid.
Shot glasses are typically filled with a liquid or fluid mixture using a pitcher, ladle, martini shaker, or measuring cup. All these instruments yield messy, inaccurate results with much waste. What is needed is a dispenser that efficiently and accurately fills shot glasses. The dispenser should be able to accommodate hot liquids as well as room temperature or cold liquids, and the dispenser should be easy to use.
The shot dispenser of the present invention fills a shot glass efficiently and accurately without spillage; using gravity to facilitate all liquid being used. Furthermore, it holds a large amount of liquid to make mass quantities of shots at once. The shot dispenser is ergonomically friendly, incorporating a handle so that hot liquids can also be used without warming and/or burning the user's hands. The one-touch operation of the valve stem to the floor of the receptacle increases the accuracy of fill dramatically to all known technology.
SUMMARY OF THE INVENTION
A liquid dispenser is provided having a container spout that is an orifice without any valve mechanism. The container spout may be attached to a funnel having a handle. In one embodiment, the funnel may be supported by a stand. An elongated tube extends from the container spout. The elongated tube includes a flexible tube in fluid communication with the container spout at a proximal end. The elongated tube also includes a rigid tube in fluid communication with a distal end of the flexible tube and extending to a dispensing end. A valve is situated at the dispensing end of the rigid tube.
The funnel holds a liquid or other fluid that is prevented from being dispensed from the liquid dispenser by the valve. A tip of the valve may be pressed against a bottom surface of a container, i.e. a shot glass, to open the valve and dispense the liquid therefrom. The rigid tube provides strength to the elongated tube to enable enough pressure to open the valve. While dispensing the liquid, a height between the container spout and the valve may be adjusted to adjust or control a flow rate of the liquid through the liquid dispenser.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will become more fully understood from the detailed description and the accompanying drawings, FIGS. 1-4 , wherein:
FIG. 1 is a schematic view of a liquid dispenser and valves formed in accordance with an embodiment;
FIG. 2 is a perspective view of a liquid dispenser formed in accordance with another embodiment;
FIG. 3 is a side view of liquid dispensers formed in accordance with other embodiments; and
FIG. 4 are perspective views of a liquid dispenser in use and a tray with cups.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.
As illustrated in FIG. 1 , the present invention is for a liquid dispenser 10 which has a container 12 for holding a liquid or fluid 100 , an elongated tube 14 , 16 and a terminal valve 18 . As used herein the terms “liquid” and “fluid” may include liquids or fluids containing particles of ice or other material, for example a slush-like drink. In some embodiments, the elongated tube includes a flexible tube 14 at the proximal end and a rigid tube 16 at the distal end. The container is preferably a funnel 12 a with a handle 24 and has a spout 22 that is connected to one end 26 of the flexible tube 14 . Optionally, the container may be a closed top container 12 b that enables the liquid dispenser 10 to be stored on its side with liquid 100 therein. The other end 28 of the flexible tube is connected to the rigid tube 16 . The rigid tube 16 is preferably elongated 30 , extending to its dispensing end 32 where the stem valve 18 is preferably situated.
An alternative embodiment of the invention is shown in FIG. 2 . In this embodiment, the container spout has a threaded collar 36 screwed over a threaded nozzle 34 . The threaded collar has a reducer section 38 extending to an elongated tip 40 . The ends of the flexible tube respectively extend over the elongated tip and the rigid tube in a friction fit 42 sleeve arrangement. There may also be a coupler 44 between the flexible tube and the rigid tube, and the flexible tube fits over one end of the coupler in a friction fit sleeve arrangement. The other end of the coupler extends over the rigid tube in a friction fit sleeve arrangement. The container spout 22 , the flexible tube 14 , the rigid tube 16 and the valve may be separable to enable cleaning, storage or the like.
It will be appreciated that alternative valves 18 can be used with the liquid dispenser 10 of the present invention and that the container 12 can be held in place by a stand 20 . As shown in FIG. 1 , in addition to the stem valve 18 a , other valves may be a spring-loaded stem valve 18 b , a push-button spigot valve 18 c and a squeeze-handle valve 18 d . It will be appreciated that some of these alternate valves 18 may reduce the length of the rigid tube 16 , and the rigid tube could be formed integrally with the valve. Examples of these options are shown in FIG. 3 with the push-button spigot valve 18 c which has a shorter rigid tube than the stem valve and with the squeeze-handle valve 18 d which has its own rigid tube integrally formed into the handle section.
Operation of the liquid dispenser 10 is shown in FIG. 4 . The liquid 100 is poured into the funnel 12 a and flows through the flexible tube 14 and the rigid tube 16 . The valve 18 is biased closed and prevents the liquid 100 from flowing into the receptacles to be filled. The user 110 activates the valve 18 with one hand 112 a while preferably holding the funnel 12 a with the other hand 112 b . The flow of the liquid into the receptacle is gravity fed so the user can adjust the pressure using a differential in height 48 between the funnel and the terminal valve. By adjusting the pressure, a flow rate of the liquid through the fluid dispenser is adjusted. In particular, increasing the height between the funnel and the terminal valve increases a flow rate of the liquid through the liquid dispenser. Conversely, decreasing the height between the funnel and the terminal valve decreases the flow rate through the liquid dispenser.
In using the preferred dispenser 10 , the user holds the liquid-filled funnel 12 a by the handle 24 with one hand 112 a in an elevated position over the receptacles 102 to be filled. With their other hand 112 b , the user holds the tube 16 and presses the stem valve 18 a against the bottom of each of the receptacles to open the stem valve and start the flow of liquid 100 . When a receptacle is filled, the user pulls the tube away from the receptacle, thereby releasing the stem valve back to its biased-closed position to stop the flow of liquid.
The stem valve 18 a is activated by pressing the central stem tip 50 on the base of the receptacle which causes the stem tip to move inwardly into the valve housing 52 , thereby opening the valve and allowing the flow of liquid 100 . When a desired fluid level is reached in the receptacle, the user lifts the stem tip away from the base of the receptacle, and the pressure of the liquid pushes the stem tip back to its seating in the valve housing, thereby closing the valve and stopping the flow of liquid. The stem valve 18 b may have a spring 54 that biases the stem tip in the closed position. The push-button spigot valve 18 c is hand-operated. Pushing the button into the housing opens the valve which is spring-biased so that the valve closes automatically when the button is released. Similarly, with the squeeze-handle valve 18 d , the valve is opened by squeezing the handle and the valve closes automatically when the handle is released. It will be noted that each of these valve options allow the user to operate the valve and direct the location of the flow with one hand, thereby freeing the other hand to hold the funnel.
The dispenser 10 provides a convenient way to fill multiple cups 102 that may be arranged together on a table or in a tray. As one example of cups arranged in a tray, the dispenser can be used to fill cups held in a communion cup tray 46 . The communion cups are used for individual servings of wine or juice during church communion services. Unfortunately the individual communion cups may be time consuming and difficult to fill without spilling the wine or juice. The dispenser elements may be sized for use in filling the individual communion cups, particularly including the valve. With the present invention, the cups can be arranged in the tray and individually filled using the dispenser without spilling the wine or juice. Accordingly, the communion cups may be more quickly filled, while creating less spillage. Of course, the cups could alternatively be filled by the inventive liquid dispenser before they are placed in the tray.
It should be noted that the illustrated embodiments include a dispenser have a single valve. As would be understood by one of ordinary skill in the art, additional valves may be added to the dispenser so that multiple cups could be filled at the same time. For example, the dispenser may be configured with multiple valves that enable a plurality of shot glasses to be lined up and filled simultaneously. In another example, the dispenser may be configured with multiple valves that correlate with the arrangement of cups in a particular arrangement, such as cups in the communion cup tray. Accordingly, each of the communion cups may be simultaneously filled by simultaneously pressing each of the multiple valves against the bottoms of the communion cups.
The embodiments were chosen and described to best explain the principles of the invention and its practical application to persons who are skilled in the art. As various modifications could be made to the exemplary embodiments, as described above with reference to the corresponding illustrations, without departing from the scope of the invention, it is intended that all matter contained in the foregoing description and shown in the accompanying drawings shall be interpreted as illustrative rather than limiting. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto and their equivalents. | A device used to easily fill small containers, i.e. shot glasses, with hot or cold liquids, with precision and speed, without spillage. The device consists of a funnel, attached to a filler hose, with a specialized filler nozzle at the end. Liquid of choice is poured into the funnel. The liquid then flows through the hose, but will not come out until the user activates the nozzle. The nozzle is activated by gently pressing its tip on the floor of the container. The liquid dispenser device may be used to fill shot glasses with hot, liquid gelatin mixtures or can be used to fill other cups, such as communion cups. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates to the field of cottonseed processing and more particularly to delinting cottonseed after it has been ginned and before the seed is itself processed to recover oil and other useful byproducts. In greater particularity the present invention relates to improvements in both the efficiency of the delinter and ease of maintenance of the delinter by the operators.
The present invention is an improvement over the delinting apparatus disclosed in U.S. Pat. No. 4,967,448 which is the closest prior art. The '448 patent discloses the basic delinting process and components used in a delinter and its disclosure is incorporated herein by reference in its entirety. As noted in the '448 patent, unprocessed cotton brought from the field to a cotton gin for ginning will produce bales of long cotton fibers while the remaining cottonseed will have a residue of lint thereon. Cottonseed processing apparatus has long been used to remove residue lint from cottonseeds which have already been processed in conventional cotton gins to remove the long, staple fibers from the seeds. The lint removed from the cottonseed is one of the salable products procured from the cotton operation.
Lint is removed in a single pass, called mill run cut lint, or multiple passes through a cottonseed processing apparatus known as a delinter. In multiple pass processes, the first pass lint yields high quality cellulose, used in manufacturing high quality paper. Lint from the second and third passes or mill run cut lint is usually sold in blended form, with munitions lint, hygienic cottonballs and various cellulose based chemicals being common end uses.
It is also desirable to delint seeds to enhance processability for oil extraction. In oil extraction apparatus, lint is a contaminant which detracts from the overall quality of the oil and adds to the maintenance requirements for the oil extraction apparatus.
In the conventional delinter, the lint is continuously removed from seed by subjecting a rotating mass of seed or “seed roll” to a rotating, ganged cylinder of toothed saw blades passing between ribs in a “grate”. The lint is “doffed” from the saw teeth by a revolving brush cylinder.
The seed roll is rotated in a “float chamber” where the seed roll is subjected to the saws. Rotation of the seed roll is caused by a rotating paddle wheel “float” in the center of the seed roll. The density of the seed roll in the float chamber is controlled by a feedback controlled paddle wheel roll feeder upstream of the float. The rotating speed of the roll feeder is determined by the amperage required by the saw cylinder motor, such that seed roll density is maintained at an optimum level for efficient delinting. Typically, however the width of the feeder has been narrower than the width of the saw cylinder, and cottonseed was required to migrate to the ends of the cylinder in an attempt to process the seed through the saw. Rather than flowing smoothly this lateral migration created flow problems as the cottonseed tended to accumulate at the ends of the saw cylinder, resulting in split seeds with a consequent release of oil onto the lint and increased hull content in the lint discharged at both ends of the saw cylinder. Thus, recent delinters such as shown in the '448 patent, which were more energy efficient suffered from decreased quality of lint when operated at energy saving rates.
Machines used for delinting cottonseed are not to be confused with cotton gins which remove the staple fiber from the seed. Delinting apparatus use the seed cotton which has already been ginned and must be further processed to remove the residual lint from the seed. These machines operate year round rather than seasonally when the cotton is harvested and ginned. In use, the saw cylinders wear rapidly and require frequent sharpening, so a convenient means of accessing and removing the saw cylinder is required. Although the '448 patent greatly improved the access of the operator to the saw cylinder, machines built since that disclosure have suffered from significant drawbacks in operator ease of maintenance. Specifically, the prior machines have required multiple steps to remove the saw cylinder for sharpening, an event that occurs as frequently as daily over the operational life of the machine. For example, each time the saw was removed, the operator had to first loosen the tension on the drive belts from the saw motor and the float motor, then remove the belts, which required that he reach across the ends of the spindle of the saw cylinder and float cylinder and across the discharge augers, then open the gratefall with a fluid actuated cylinder sufficiently to hoist the saw cylinder out of the apparatus. No provision was made to break the circuit to the saw motor other than the on/off switch and the hydraulic cylinders used to open the gratefall had no backup to prevent uncontrolled pivoting of the gratefall during the opening process in case of a hydraulic failure. Thus, the prior system, while an improvement over earlier models was still cumbersome and dangerous.
The value or price of lint is determined by the purity of the lint fiber. The higher the foreign matter or “trash” such as broken hulls, kernels, etc. in the lint, the lower the quality. Therefore it is desirable to remove such trash from the lint in the delinter. “Moting”, the removal of trash (“motes”) from the lint, is accomplished by gravity in a moting chamber, where the heavier or more dense motes fall through an upwardly-flowing airstream created pneumatically to carry away the lint. As noted above, the value of both the seed and the lint is diminished if the seed spends too much time on the saw or is too compressed at the end of the saw cylinder such that the seed hull is torn.
Thus, it can be seen that conventional delinting apparatus currently in use suffers from a number of significant drawbacks. A need presently exists for eliminating these drawbacks, to yield delinting machinery which enables higher efficiency delinting and better quality lint than has previously been obtained.
SUMMARY OF THE PRESENT INVENTION
It is an object of the present invention to increase the capacity of the delinter over prior delinter designs while lowering energy consumption per ton of seed. Another object of the invention is to reduce the need to re-sharpen saws resulting in both longer saw life and saw sharpening file life. Still another object of the invention is decrease the amount of down time while re-sharpening each saw cylinder. A further object of the invention is to improve the quality of the lint. Yet another object of the invention is to reduce seed damage in the delinter. A significant object of the invention is to eliminate hydraulic and pneumatic cylinders in the gratefall operation to simplify and enhance the safety of the saw removal process.
These and other objects and advantages of the invention will become apparent from the following detailed description of the preferred embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
An apparatus for delinting cottonseed is depicted in the accompanying drawings which form a portion of this disclosure and wherein:
FIG. 1 is a side elevation view of the delinter showing the drive components for the saw cylinder;
FIG. 2 is a side elevation view of the opposite side of the delinter showing the drive components for the float and doffing brush;
FIG. 3 is a front elevation view of the delinter
FIG. 4 a to 4 d are side elevation views showing the sequence of opening the gratefall and loosening the saw drive belt
FIG. 5 is a detail of the transition from the feeder to the gratefall
FIG. 6 is a detail of the float assembly.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the FIGS. 1-4 for a clearer understanding of the invention, it may be seen that the preferred embodiment of the invention contemplates a delinter 10 having the same major components as the delinter shown in the '448 patent, namely a feeder 11 , a lint discharge 12 , a motes conveyor 13 , a seed conveyor 14 , a housing 20 , including various access doors and windows. A float 16 and chamber 17 is defined beneath feeder 11 within the housing 20 and above a saw cylinder 22 which carries a plurality of saws 24 . A doffing cylinder is provided to conventionally doff the lint from the saws.
In the '448 patent, the disclosed gratefall assembly supported the float and was linked to the saw cylinder supports such that opening the gratefall exposed the saw cylinder and moved it to a position where it could be hoisted vertically. However, the gratefall was moved between the open and closed positions by a hydraulic cylinder mounted outside the gratefall assembly. The drive belts for the float and the saw cylinder were tensioned by separate pneumatic cylinders. In that design the tension had to be released and the drive belts for both the float and saw removed before the gratefall could be opened. This required the operator to undertake several steps to open the gratefall including removing the belts while leaning over the motes and seed conveyors.
The present invention eliminates all hydraulic and pneumatic cylinders and releases the tension on the saw and float belts while the gratefall transitions from the closed to open position, thus eliminating several steps and allowing the operator to remove the belts as needed from the front of the machines and also eliminates or replaces other forms of removing saw cylinder. Referring to FIGS. 1 to 4 in the current design, saw motor 31 drives take-off belt 32 , to sheave 33 which is mounted to housing 11 at a fixed location. A saw belt 35 is also entrained about sheave 33 and saw drive sheave 36 which is mounted on saw pivot arms 38 on each side of the delinter are pivotally rotated with gratefall assembly 41 about the same axis passing through pivot shaft 39 , thus the saw drive sheave 36 is movable with the gratefall assembly 41 . Mounted to the saw cylinder pivot arm 38 and pivot shaft 39 , and interposed between sheave 33 and saw drive sheave 36 is the saw idler assembly 51 Saw idler assembly 51 includes a fixed idler bracket 52 pivotally mounted for movement about pivot shaft 39 in fixed relation to gratefall assembly 41 and a floating idler bracket 53 also mounted for movement about pivot shaft 39 at a selected angle offset from fixed idler bracket 52 . The offset between brackets 52 and 53 is maintained by rod adjustably connected there between. Bracket 52 carries a belt idler pulley 56 which engages saw belt 35 forwardly of pivot shaft 39 and bracket 53 carries a belt idler pulley 57 which engages belt 35 rearwardly of pivot shaft 39 and serves as a tensioning pulley. The tension on the belt is adjusted by varying the angle between brackets 52 and 53 . On the opposite side of the delinter 10 a float take-off belt 62 is driven by float motor 61 about a sheave 63 mounted to housing 11 at a fixed location. A float belt 65 is entrained about sheave 63 and float drive sheave 64 . A float idler assembly 71 which is the mirror image of saw idler assembly 51 and includes a fixed bracket 72 , floating bracket 73 , positioning rod, belt idler pulley 76 , and belt tensioning pulley 77 both of which engage the float belt 65 in the same manner as described above. It will be noted that pivot shaft 38 is offset from a direct line between sheaves 33 , 63 and drive sheaves 36 , 64 , thus engagement of belts 35 , 65 , by the idler pulleys 56 , 76 and 57 , 77 give the belts a L shaped configuration when properly tensioned.
A pair of jack screws 81 , 82 are mounted to the housing and connected to the pivot arms 38 to urge the pivot arms about the pivot axis in opening and closing the gratefall assembly 41 . An electric motor 83 elongates and shortens the jack screws. When the jack screws are elongated they urge the drive sheaves 36 , 64 carried by the gratefall assembly 41 away from the fixed sheaves 33 , 63 , thus making the L shape of the drive belts 35 , 65 more obtuse as shown in FIG. 2 a to 2 d and moving idler pulleys 56 , 76 closer to drive sheaves 33 , 63 thus releasing the tension on the belts 35 , 65 such that when the grate fall is completely open the saw belt 35 may be easily removed or replaced on the sheaves at a convenient level directly in front of the operator. The float belt 65 is loosened but does not need to be removed from the drive sheave to remove the saw cylinder. It should be therefore apparent that the operation of opening the gratefall and removing the saw cylinder for sharpening or maintenance is greatly simplified. Note that since the doffing roll is not mounted to the gratefall assembly 41 , it does not move and doffing roll belt 92 remains tensioned between sheave 63 and doffing drive sheave 93 , in as much as the float and doffing roller are driven by the same motor.
It should be noted that jackscrews 81 , 82 provide a positive mechanical linkage to the gratefall assembly 41 , thus if electrical power is lost during the movement of the gratefall the jackscrew will stop and the gratefall assembly will remain in its then current position rather than falling under the influence of gravity as could occur with a hydraulic system. It is also noteworthy that limit switches are in the circuit energizing saw motor 21 and float motor 61 . These limit switches open when the gratefall assembly begins to move from the closed position de-energizing the saw circuit and thus insuring that none of the belts, motors or sheaves are energized during the saw cylinder change out process.
It should be noted that feeder 11 is the same width as saw cylinder 22 , thus seed entering the float chamber 17 and urged toward the saws 24 is able to pass vertically through the delinter without the need to migrate laterally as was the case in the delinter shown in the '448 patent. Accordingly the seed can be processed more quickly and no build up or accumulation of seeds at any region across the saw cylinder 22 is encountered, thereby reducing the dwell time of the seed on the saws 24 and reducing the prospect of slicing the seed and contaminating the lint with hull or oil produced by the machine.
Aiding in the direct processing of the seed cotton from the feeder to the saws is the redesign of the entry to the float chamber 17 in the gratefall assembly 41 . The rear scroll 101 has been extended and turned nearly 90 degrees at the entrance from the feeder so that a smooth surface with no transitions between metal parts are presented except where the scroll 101 abuts frame plate 102 . Likewise, the seed board 103 has been redesigned to reduce friction at the inlet from the feeder 11 , by turning the upper edge of the plate forming the seed board away from the inlet, thereby eliminating a part to part transition and improving the flow characteristics of the cotton seed.
A further refinement in flow is achieved by adding end caps 101 to the float which rotate with the float vanes as seen in FIG. 6 . Traditional floats did not have endcaps thus creating friction and accumulation of cottonseed at the float vane and gratefall sideplate interface which exerts extra pressure against the gratefall side plates and forces most of the seed to be discharged at each end of the float chamber causing uneven delinting of the seed. By improving the flow of the cottonseed from the wider feeder through the smother entrance and across the more efficient float, the quality of the lint produced by the machine and the efficiency of the delinter is greatly improved. This is particularly so, when the saws 24 themselves are configured differently. More specifically, prior to the introduction of the '448 delinter the saw teeth were formed with a tangent line intersecting a 12″ diameter saw. The '448 design used an 18″ diameter saw with a tangent designed for that saw diameter, however, this saw tooth design was more likely to rip the seed hull. Thus, some prior art machines were retrofitted with 18″ diameter saws in on which the tangent line of the tooth was the same as had been used on a 12″ diameter saw. This reduced the damage to the hull considerably, but did not provide the efficient operation and significantly improved quality lint which is achieved when the feeder is widened, the float capped and the transition from feeder to gratefall is smoothed in addition to using the 12″ tangent line tooth on an 18″ saw.
It is to be understood that the form of the invention shown is a preferred embodiment thereof and that various changes and modifications may be made therein without departing from the spirit of the invention or scope as defined in the following claims. | A delinter apparatus for seed cotton includes a jack screw displacement system for a gratefall which opens the apparatus for removal of a saw cylinder while urging a plurality of belt tensioning idlers into a relaxed position such that the drive belt for the saw cylinder can be removed in a simplified and more efficient manner. The apparatus also has improved flow characteristics due to improvements in the lint feeder design as well as the transition designs from the feeder to the float chamber and saw interface. | 3 |
CLAIM OF PRIORITY
[0001] This application claims the benefit of priority under 35 U.S.C. §119 from a Korean patent application filed in the Korean Intellectual Property Office on Dec. 2, 2008 and assigned Serial No. 10-2008-0121109, the entire disclosure of which is hereby incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to portable terminals having a broadcasting function. More particularly, the present invention relates to a method that receives and reproduces a plurality of mobile broadcasts whose broadcast communication standards differ from each other, and a multi-standby terminal adapted to operate in accordance with the method.
[0004] 2. Description of the Related Art
[0005] In recent years, portable terminals have included a variety of options, such as an MP3 player, a mobile broadcast reception function, a moving image reproduction function, a camera, etc. In particular, the mobile broadcast reception function allows portable terminals to provide a broadcasting service during movement. To improve interoperability, a variety of broadcasting standards have been developed in the mobile broadcast communication area. Examples of such broadcasting standards are a digital video broadcasting-handheld (DVB-H), a mediaFLO, a multi-media broadcasting multi-casting service (MBMS), etc.
[0006] Although such a variety of broadcast communication standards have been developed, their standardization has not yet been completed. Service providers have recently started providing a mobile broadcasting service using the broadcast communication standards.
[0007] Conventional portable terminals having a mobile broadcast reception function can reproduce broadcast signals according to only a single broadcast communication standard. Therefore, if the conventional portable terminals move from their original broadcasting service area to areas where broadcasting services having different broadcast communication standards are provided, such conventional portable terminals cannot reproduce broadcasts in these visited areas. In order to receive broadcasts in a visited area, users must use portable terminals that can reproduce broadcast signals according to the broadcast communication standard of the visited area. It is not uncommon for one to rent a portable terminal when on a business trip, for example. However, renting a portable terminal is inconvenient, costly, and potentially comprises the privacy of communication information in the rented phone, such as personal telephone numbers of colleagues, family, text message data, etc.
SUMMARY OF THE INVENTION
[0008] The present invention provides a method that receives and reproduces a plurality of mobile broadcasts whose broadcast communication standards differ from each other, and a multi-standby terminal adapted to the method.
[0009] In accordance with an exemplary embodiment of the present invention, the present invention provides a method for reproducing mobile broadcasts in a multi-standby terminal, including: receiving a first broadcast signal according to a first broadcast communication standard; reproducing the first broadcast signal using a first authentication processor; comparing a received signal strength indication (RSSI) of a second broadcast signal with an RSSI of the first broadcast signal, if the second broadcast signal according to a second broadcast communication standard is received during the reproduction of the first broadcast signal; and reproducing the second broadcast signal using a second authentication processor if an RSSI of the second broadcast signal is greater than an RSSI of the first broadcast signal.
[0010] In accordance with another exemplary embodiment of the present invention, the present invention provides a multi-standby terminal including: a first broadcast receiver for receiving a first broadcast signal according to a first broadcast communication standard; a second broadcast receiver for receiving a second broadcast signal according to a second broadcast communication standard; a storage unit for storing a first authentication processor for reproducing the first broadcast signal and a second authentication processor for reproducing the second broadcast signal; and a controller for comparing a received signal strength indication (RSSI) of the second broadcast signal with an RSSI of the first broadcast signal if a broadcast reception function is activated, and reproducing one of the first and second broadcast signals whose RSSI is greater than that of the other signal.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The above and other illustrative aspects, features and advantages of certain exemplary embodiments of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawing, in which:
[0012] FIG. 1 is a view illustrating a broadcast communication system according to an exemplary embodiment of the present invention;
[0013] FIG. 2 is a view illustrating a schematic block diagram illustrating a multi-standby terminal according to an exemplary embodiment of the present invention; and
[0014] FIG. 3 is a flow chart describing a method for reproducing broadcasts in a multi-standby terminal according to an exemplary embodiment of the present invention.
DETAILED DESCRIPTION
[0015] Hereinafter, exemplary embodiments of the present invention are described in detail with reference to the accompanying drawings. Detailed descriptions of well-known functions and structures incorporated herein may be omitted to avoid obscuring appreciation of the subject matter of the present invention by a person of ordinary skill in the art.
[0016] Prior to discussing certain exemplary embodiments of the present invention, terminologies will be defined as used in the present description herein below. The terms or words described in the present description and the claims should not be limited by a general or lexical meaning, instead should be analyzed as a meaning and a concept through which the inventor defines and describes the present invention at his most effort, to comply with the idea of the present invention. Therefore, one skilled in the art will understand that the exemplary embodiments disclosed in the description and configurations illustrated in the drawings are only preferred exemplary embodiments, and there are various modifications, alterations, and equivalents thereof that lie within the sprit of the invention and the scope of the appended claims.
[0017] In the following description, the term ‘authentication key’ refers to a way to identify a right to receive broadcast signals provide by a broadcasting service provider. In an exemplary embodiment of the present invention, the authentication key is stored in a subscriber identity module (SIM) card.
[0018] The term ‘authentication processor’ refers to a program that processes and reproduces received broadcast signals according to a broadcast communication standard. The authentication processor may require an authentication key to reproduce a broadcast signal that is set as a reception restriction function.
[0019] The term ‘subscriber identity module (SIM)’ refers to a commonly called card that stores subscriber identification information through which users can enjoy a variety of services, such as a subscriber authentication, billing, security function, etc. It should be understood that the present invention may also be implemented with a universal SIM (USIM), or other types of modules that would include such identification, authentication and authorization information, just to name a few items.
[0020] FIG. 1 is a view illustrating a broadcast communication system according to an exemplary embodiment of the present invention.
[0021] Referring now to FIG. 1 , the broadcast communication system 1000 preferably includes a first broadcast communication network 100 , a second broadcast communication network 200 , and a multi-standby terminal 300 .
[0022] The first broadcast communication network 100 provides a broadcasting service using one of a plurality of broadcast communication standards. For example, the first network 100 transmits a first broadcast signal according to a first broadcast communication standard to a first broadcasting service area 10 . In an exemplary embodiment of the present invention, the broadcasting standard may be implemented by one of the digital video broadcasting-handheld (DVB-H), mediaFLO, and multi-media broadcasting multi-casting service (MBMS), etc.
[0023] The second broadcast communication network 200 provides a broadcasting service using a broadcast communication standard that differs from that of the first broadcast communication network 100 . For example, the second network 200 transmits a second broadcast signal according to a second broadcast communication standard to a second broadcasting service area 20 . The first broadcast communication standard and the second broadcast communication standard utilize different communication protocols by which the respective first broadcast signal and second broadcast signal are broadcast.
[0024] The multi-standby terminal 300 receives and reproduces the broadcast signals from both the first and second broadcast networks. To this end, it includes a plurality of broadcasting authentication processors. For example, the multi-standby terminal 300 may include a first authentication processor for reproducing the first broadcast signals transmitted from the first broadcast communication network 100 , and a second authentication processor for reproducing the second broadcast signals transmitted from the second broadcast communication network 200 . It is within the spirit and scope of the present invention that one processor could logically function as two logical authentication processors. In an exemplary embodiment of the present invention, the first and second authentication processors may be implemented with a Multimedia Broadcasting Business Management System (MBBMS) and a BroadCast/MultiCast Service (BCMCS), respectively. It should be understood that the present invention is not limited to the exemplary embodiment discussed herein. For example, the first and second authentication processors can employ a variety of communication methods according to broadcast communication standards. The multi-standby terminal according to the present invention can be achieved by combining the first authentication processor with the second authentication processor.
[0025] If the multi-standby terminal 300 is located in the first broadcasting service area 10 , it reproduces the first broadcast signal using the first authentication processor. If the multi-standby terminal 300 moves to the second broadcasting service area 20 , said multi-standby terminal 300 can reproduce the second broadcast signal using the second authentication processor. The first and second authentication processors can be implemented with a middleware and stored in the multi-standby terminal 300 .
[0026] If the multi-standby terminal 300 is located in an area where the first and second service areas 10 and 20 overlap, the multi-standby terminal 300 compares received signal strength indications (RSSIs) of transmitted broadcast signals from the first and second broadcast communication networks 100 and 200 , and reproduces a received broadcast signal whose RSSI is greater than the other signal. The multi-standby terminal 300 may display a selection window through which a user can select a broadcast to be reproduced. On the contrary, if the multi-standby terminal 300 does not receive both the first and second broadcast signals, the multi-standby terminal 300 displays a message indicating that receiving the broadcast is impossible.
[0027] A description has been provided regarding the broadcast communication according to an exemplary embodiment of the present invention. In the following description, a configuration of the multi-standby terminal is explained in detail with reference to FIG. 2 .
[0028] FIG. 2 is a view illustrating a schematic block diagram illustrating a multi-standby terminal according to an exemplary embodiment of the present invention.
[0029] Referring now to FIG. 2 , the multi-standby terminal 300 includes a broadcast receiving unit 350 , a display unit 330 , a storage unit 320 , an interface unit 340 , and a controlling unit 310 .
[0030] The display unit 330 displays a variety of menu screens for the multi-standby terminal 300 , user's input data, function setting information, etc., and a variety of information to be provided to a user. If the display unit 330 is implemented with a touch screen, the display unit 330 can also serve as an input device. The display unit 330 may be implemented with a liquid crystal display (LCD), an organic light emitting diode (OLED), etc. In an exemplary embodiment of the present invention, if the multi-standby terminal 300 simultaneously receives a plurality of broadcast signals whose broadcast communication standards differ from each other, for example, first and second broadcast signals from first and second communication networks 100 and 200 (such as shown in FIG. 1 ), the display unit 330 preferably displays a selection window under the control of the controlling unit 310 , so that a user can select one of the received first and second broadcast signals through the selection widow. If the multi-standby terminal 300 does not receive both the first and second broadcast signals, the display unit 330 displays a message indicating that impossible to receive a broadcast, under the control of the controlling unit 310 . A person of ordinary skill in the art should understand that the present invention is not limited to a user selection at the time of reception and may have a default based on items such as, for example, signal strength, or if a particular message is identified as an emergency message.
[0031] The broadcast receiving unit 350 serves to receive broadcast signals. It may also receive broadcast signals whose broadcast communication standards differ from each other. To this end, the broadcast receiving unit 350 includes first and second broadcast receivers 51 and 52 for receiving first and second broadcast signals according to first and second broadcast communication standards, respectively. While one antenna is shown in FIG. 2 , it is within the spirit of the invention that each receiver can have a separate antenna, particularly if there are different frequency bands received.
[0032] In an exemplary embodiment of the present invention, although the broadcast receiving unit 350 is implemented to include two broadcast receivers 51 and 52 , it should be understood that the present invention is not limited to the exemplary embodiment. For example, the embodiment may be modified to include three or more broadcast receivers to receive three or more broadcast signals. If the broadcast receivers have the same modulation methods of the broadcast signals and the same frequency bands, the broadcast receiving unit 350 may receive a plurality of broadcast signals using one broadcast receiver.
[0033] The interface unit 340 refers to a device that receives subscriber identification module (SIM) cards. It may include first and second slots 41 and 42 . For example, the first slot 41 receives a first SIM card, and the second slot 42 receives a second SIM card. The first SIM card may comprise a mobile communication SIM card employing a Time-Division Synchronous Code Division Multiple Access (TD-SCDMA). Similarly, the second SIM card may comprise a mobile communication SIM card employing a Code Division Multiple Access (CDMA). In an exemplary embodiment of the present invention, the first SIM card may store a first authentication key to identify a right to receive the first broadcast signal. Similarly, the second SIM card may store a second authentication key to identify a right to receive the second broadcast signal.
[0034] As described above, although the exemplary embodiment is implemented in such a way that the first and second SIM cards store the first and second authentication keys, respectively, it should be understood that the present invention is not limited to the embodiment. For example, the first and second authentication keys may be stored in the storage unit of the multi-standby terminal 300 or in a server of a broadcast service provider, according to authentication methods required by the broadcast service provider.
[0035] The storage unit 320 stores application programs required to operate the multi-standby terminal 300 . For example, it stores an operation system (OS) for booting the multi-standby terminal 300 , an application program for processing a message service, and application programs for reproducing audio, images, moving images, and mobile broadcast signals. The storage unit 320 also stores data generated as the multi-standby terminal 300 is used, moving image data, audio data, contents, etc. In an embodiment of the present invention, the storage unit 320 includes first and second authentication processors 21 and 22 for reproducing first and second broadcast signals according to first and second broadcast communication standards, respectively. The first and second authentication processors 21 and 22 may comprise Open Mobile Alliance-BroadCASting (OMA-BCAST), Conditional Access System (CAS), Multimedia Broadcasting Business Management System (MBBMS), Broad-Casting Multi-Casting Service (BCMCS), etc. In an exemplary embodiment of the present invention, the first authentication processor 21 comprises MBBS and the second authentication processor 22 comprises MCMCS. These first and second authentication processors 21 and 22 can be implemented with a middleware and stored in the storage unit 320 .
[0036] Although the exemplary embodiment of the present invention is implemented in such a way that the storage unit 320 stores two authentication processors, a person or ordinary skill in the art should be understand that the present invention is not limited to the exemplary embodiments shown and described herein. For example, the storage unit 320 can store various types and amounts of authentication processors according to the specification of the multi-standby terminal and the request of service providers. There also may be more than one storage unit, and certain items dedicated to being stored in a particular unit. The first authentication processor 21 and the second authentication processor 22 may be realized in machine readable code, software or IC (Integrated Circuit) chip according to authentication method.
[0037] The controlling unit 310 controls the entire operation of the multi-standby terminal 300 and signal flows among the elements therein. The controlling unit 310 may be configured to include first and second controllers 11 and 12 . The first controller 11 or the second controller 12 may serve as a primary controller. In that case, the other serves as a sub controller.
[0038] If the broadcast receiving unit 350 receives both the first and second broadcast signals according to the first and second broadcast communication standards, respectively, the controlling unit 310 compares RSSIs of the received first and second broadcast signals. According to the comparison result, the controlling unit 310 can reproduce the received broadcast signals that have a comparatively higher RSSI. Alternatively, the controlling unit 310 may control the display unit 330 to display a selection window so that the user can select one of the first and second broadcast signals therethrough. On the contrary, if the broadcast receiving unit 350 does not receive the first and second broadcast signals, the controlling unit 310 displays a message indicating that broadcast cannot be received on the display unit 330 .
[0039] In addition, if the first or second broadcast signal is set to a receiving restriction function, such as a pay-per-view service or a viewing age restriction, the controlling unit 310 checks first and second authentication keys stored in the first and second SIM cards and identifies rights to receive the first and second broadcast signals, respectively.
[0040] Although not shown in the drawings, the multi-standby terminal 300 may further selectively include a camera module for capturing images or moving images, a short-range communication module for performing short-range wireless communication, an audio signal output unit such as a speaker, a voice signal input unit such as a microphone, a digital audio source reproducing module such as an MP3 module, etc. A person of ordinary skill in the art should understand and appreciate that the multi-standby terminal according to the presently claimed invention is not limited to include only the listed elements. With the convergence of digital devices, there are many digital devices and modifications thereof, not listed in the application, and, the artisan should certainly appreciate that such devices and modifications thereof can also be included in the multi-standby terminal 300 .
[0041] The multi-standby terminal 300 having the elements described above may also reproduce a plurality of broadcast signals whose broadcast communication standards differ from each other. Therefore, although the multi-standby terminal 300 is moved from a first broadcasting service area to a second broadcasting service area where a broadcasting service is served with a broadcast communication standard that differs from that of the first broadcasting service area, the multi-standby terminal 300 can receive the second broadcasting service, which provides convenience to the user who is viewing broadcasts.
[0042] As described above, an explanation has been provided regarding the configuration and operation of the multi-standby terminal 300 according to an exemplary embodiment of the present invention. In the following description, a method is explained in detail that reproduces mobile broadcasts in the multi-standby terminal with reference to FIG. 3 .
[0043] FIG. 3 is a flow chart describing a method for reproducing broadcasts in a multi-standby terminal according to an exemplary embodiment of the present invention.
[0044] For explanatory purposes, there is an assumption in this exemplary embodiment that the multi-standby terminal 300 location moves from a first broadcasting service area to a second broadcasting service area while the multi-standby terminal 300 is receiving a first broadcast signal in the first broadcasting service area.
[0045] Referring now to FIGS. 2 and 3 , after the multi-standby terminal 300 is turned on, the controlling unit 310 allows the multi-standby terminal 300 to be operated in a standby/idle state ( 301 ). The controlling unit 310 detects whether or not a broadcast reception function has been activated ( 303 ). When the controlling unit 310 detects that a broadcast reception function has been activated (at 303 ), the controlling unit 310 then determines whether the multi-standby terminal 300 has received a first broadcast signal according to the first broadcast communication standard ( 304 ).
[0046] At step 304 , if the controlling unit 310 ascertains that the multi-standby terminal 300 did not receive a first broadcast signal, the controlling unit 310 then determines whether the multi-standby terminal 300 has received a second broadcast signal according to the second broadcast communication standard ( 306 ). When the controlling unit 310 ascertains that the multi-standby terminal 300 has not received a second broadcast signal at 306 , the controlling unit 310 controls the display unit 330 to display a message indicating that a broadcast cannot be received ( 307 ), and then terminates the procedure. On the contrary, when the controlling unit 310 ascertains that the multi-standby terminal receives a second broadcast signal at 306 , the controlling unit 310 controls to reproduce the received second broadcast signal ( 311 ).
[0047] Meanwhile, if the controlling unit 310 ascertains that the multi-standby terminal receives a first broadcast signal at 304 , the controlling unit reproduces the received first broadcast signal ( 305 ) in conjunction with other units, such as shown in FIG. 2 . The controlling unit 310 may reproduce the first broadcast signal using a first authentication processor 21 . In an exemplary embodiment of the present invention, the first authentication processor 21 may comprise a multi-media broadcasting business management system (MBBMS). The first authentication processor 21 can be implemented with a middleware.
[0048] During the reproduction of the first broadcast signal, the controlling unit 310 detects whether or not the multi-standby terminal 300 has received a second broadcast signal ( 308 ). If the controlling unit 310 ascertains that the multi-standby terminal 300 has received a second broadcast signal at 308 , the controlling unit 310 compares an RSSI of the received second broadcast signal with that of the first broadcast signal ( 310 ).
[0049] If the controlling unit 310 ascertains that an RSSI of the received second broadcast signal is greater than the RSSI of the first broadcast signal at 310 , the controlling unit 310 reproduces the second broadcast signal at 311 . The controlling unit 310 may reproduce the second broadcast signal using a second authentication processor 22 that differs from the first authentication processor 21 . In an exemplary embodiment of the present invention, the second authentication processor 22 may comprise a BroadCast/MultiCast Service (BCMCS). The second authentication processor 22 can be implemented with a middleware.
[0050] On the contrary, if the controlling unit 310 ascertains that an RSSI of the received second broadcast signal is equal to or less than that of the first broadcast signal at 310 , the controlling unit 310 continues to reproduce the first broadcast signal at 305 .
[0051] Although not explained in the foregoing description, if the first or second broadcast signal is set to a receiving restriction function, such as a pay-per-view service or a viewing age restriction, the controlling unit 310 can identify a right to receive the first or second broadcast signal. That is, the controlling unit 310 can check whether a first authentication key is stored in the first SIM card to identify the right to receive the first broadcast signal. Alternatively, the controlling unit 310 can check whether a second authentication key is stored in the second SIM card so as to identify the right to receive the second broadcast signal. The first SIM card may be implemented, for example, employing a Time-Division Synchronous Code Division Multiple Access (TD-SCDMA). The second SIM card may be implemented using a Code Division Multiple Access (CDMA), for example.
[0052] Although an exemplary embodiment of the present invention is implemented in such a way that first and second authentication keys are stored in SIM cards, the artisan should be understand that the present invention is not limited to the exemplary embodiments shown and described. For example, the first and second authentication keys may be stored, for example in the storage unit of the multi-standby terminal or in a server of a broadcast service provider.
[0053] In an exemplary embodiment of the present invention, although the SIM card may be implemented by a TD-SCDMA SIM card and a CDMA SIM card, the artisan should be understand that the present invention is not limited to the exemplary embodiments shown and described. That is, the SIM card may be implemented with a variety of interfaces.
[0054] Although the embodiment of the present invention is implemented in such a way that a determination is made as to whether the multi-standby terminal receives a second broadcast signal during the reproduction of the first broadcast signal, it should be understood that the present invention is not limited to the embodiment. The embodiment may be modified in such a way to determine whether the multi-standby terminal receives a first broadcast signal during the reproduction of the second broadcast signal.
[0055] As described herein above, the mobile broadcast reproducing method, according to the present invention, can reproduce a plurality of mobile broadcasts whose broadcast communication standards differ from each other in a multi-standby terminal, so that users can view broadcasts through a single multi-standby terminal adapted to the method. The mobile broadcast reproducing method and the multi-standby terminal adapted to the method can provide high quality broadcasts even in an area where a plurality of broadcast services overlap. In addition, the above-described methods according to the present invention can be realized in hardware, middleware, or as software or computer code that can be stored as machine readable code in a medium such as a ROM, an RAM, a floppy disk, a hard disk, or a magneto-optical disk or downloaded over a network, so that the methods described herein can be rendered in such software using a general purpose microprocessor, or a special processor or in programmable or dedicated hardware, such as an ASIC or FPGA.
[0056] As would be understood in the art, the computer, the processor or the programmable hardware include memory components, e.g., RAM, ROM, Flash, etc. that may store or receive software or computer code that when accessed and executed by the computer, processor or hardware implement the processing methods described herein.
[0057] Although the invention has been shown and described with respect to certain exemplary embodiments thereof, the artisan should understand that these exemplary embodiments are only illustrative and not intended to limit the scope of the invention. Therefore, one skilled in the art will understand that the exemplary embodiments disclosed in the description and configurations illustrated in the drawings are only preferred exemplary embodiments, and there may be various modifications, alterations, and equivalents thereof, without departing from the scope and sprit of the invention as described in the accompanying claims. | A mobile broadcast reproducing method and a multi-standby terminal permit a terminal to receive broadcasts from different broadcast networks having different standards and even different broadcasting frequencies. The multi-standby terminal communicates with a variety of communication networks preferably includes a plurality of authentication processors and reproduces broadcast signals according to a variety of broadcast communication standards using the authentication processors. The terminal can also compare the a received signal strength indication (RSSI) of different networks and permit the user the option of selecting one of them based on this comparison, or can automatically select the broadcast having stronger RSSI signal. | 7 |
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention is directed toward pivoting windows, and more particularly toward a powered operator for a casement window sash.
2. Background Art
Motorized casement window operators have been implemented in the art for mechanically opening and closing a window sash relative to a window frame. For example, Vetter U.S. Pat. No. 4,497,135, Berner et al. U.S. Pat. No. 4,945,678 (Reissue U.S. Pat. No. 34,287), Midas U.S. Pat. No. 5,313,737, and Vetter et al. U.S. Pat. No. 5,493,813 all specifically disclose various motorized casement window hinges. In addition, it has been known to connect motor drives to the drive shaft of conventional manual window operators to retrofit such operators for motorized operation.
However, these prior art are often difficult to retrofit into existing construction without requiring that the window frame and/or surrounding wall be destroyed to fit components. In some installations (such as areas with old wallpaper), the destroyed wall/frame parts cannot be readily repaired to their original condition.
Further, with those prior art structures which can be more readily retrofit in existing installations, the resulting operator is generally obtrusively large. This tends to detract from the beauty of the wood or vinyl wrapped window and/or intrudes into the desired visual opening through the window.
Still further, with many prior art power window operators, there is an unacceptably high level of noise and high cost. Still further, retrofitting a power system to use the existing hardware results in very low operating speeds, since locating the retrofitted system at the optimum kinematic position is nearly impossible. Further, the prior art power window operators do not include the window itself in their design. This detracts from the window's aesthetic features, and makes it difficult to paint or stain the window, since the painter has to work around or cover up the implemented hardware for the power system.
The present invention is directed toward overcoming one or more of the problems discussed above.
SUMMARY OF THE INVENTION
In one aspect of the present invention, an assembly is provided for opening and closing a window sash from and against a window frame. The assembly includes a motor mounted to a window sash and having an output drive shaft, an operator arm having one portion pivotally connected to the sash and a second portion operably connected to the frame, means for operably connecting the motor drive shaft to the operator arm for controlling pivotal movement thereof in relation to the sash, and means for selectively controlling the motor.
In another aspect of the present invention, the assembly includes manually operable means for selectively releasing the operably connecting means to allow the sash to move independent of the motor drive shaft.
In preferred forms of this aspect of the present invention, the operably connecting means includes a gear reducing train operably connected to the motor drive shaft, driving means operably connected to the gear reducing train, and means for operably connecting the driving means to the operator arm for controlling pivotal movement thereof in relation to the sash.
In another preferred form of this aspect of the present invention, the assembly includes a housing disposable in a cavity defined in a generally rectangular box shape on a sash side, with the motor, the gear reducing train, the driving means, and the means for operably connecting the driving means to the operator arm being disposed in said housing.
In another preferred form of this aspect of the present invention, an integral mounting structure is provided for mounting a window sash control system to a window sash. The structure includes a window sash on one side having a substantially rectangular box shape with a selected thickness, a generally box-shaped cavity defined in the one sash side with finger-joints on the sash at opposite ends of the cavity, the cavity having a depth substantially equal to the selected thickness of the one sash side, and a generally box-shaped housing having two end walls connected by two side walls with at least one closing wall connected to the end walls and the side walls, the walls defining an enclosure adapted to receive a window sash control system. The end walls have matching finger-joints which engage the finger-joints on the opposite ends of the sash cavity, and the side walls each have substantially planar outer surfaces, with the outer surfaces substantially conforming to the outer surfaces of the one sash side.
In another preferred form of this aspect of the present invention, the housing walls are thermally non-conductive, and the housing finger-joints are adhesively bonded to the sash finger-joints.
One object of the present invention is to provide a power window operator which does not interfere with or detract from the beauty of the window.
Another object of the present invention is to provide a power window operator which will not intrude into the desired visual opening.
Still another object of the present invention is to provide a power window operator which incorporates the window itself in its design.
Yet another object of the present invention is to provide a power window operator with low noise levels and at a low cost.
It is another object of the present invention to provide a power window operator having a high operating speed.
It is still another object of the present invention to provide a power window operator which will not interfere with the maintenance of the window unit, such as painting, nor will it adversely affect the strength of the window unit over time.
It is yet another object of the present invention to provide an housing structure for suitably mounting a window sash control system to a window sash.
Still another object of the present invention is to provide a power window operator structure which may be easily retrofitted into existing construction.
Other objects and features of the invention will be readily apparent from the specification taken in view of the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a window embodying a first embodiment of the power window operator of the present invention, with the components of the power window operator internal to the sash shown in phantom;
FIG. 2 is a perspective view of the power window operator of FIG. 1, with part of the housing removed;
FIG. 3 is a partial perspective view of a window embodying a second embodiment of the power window operator of the present invention;
FIG. 4 is a perspective view of the power window operator of FIG. 3, with part of the housing removed; and
FIG. 5 is a plan view of the power window operator as viewed from above FIG. 4.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, a power window operator generally indicated by 10 is mounted to a side of a window sash 12. The window sash 12 is, in a preferred embodiment, part of a casement window which is pivotally mounted to a window frame or jamb, shown generally in phantom at 14, by the power window operator 10 and a suitable casement hinge 16 secured to the opposite side of the jamb 14 and sash 12.
It should be understood that though the description herein generally refers to casement windows, the present invention could also be used with a variety of different window types, including awning windows, french windows and skylights, as well as windows made of a variety of different materials, such as wood or vinyl wrap windows.
Power window operator 10, which will hereafter be described, is only one example of a type of power window operator which would benefit from incorporating the present invention. Though the particular power operator structure such as disclosed herein may be advantageously used with the present invention, once a full understanding of the present invention is obtained, it should be recognized that still other operator configurations for moving the sash relative to the jamb could also be advantageously used with the present invention.
Referring now to FIG. 2, the power window operator 10 is comprised of a motor 18, a gear reducing train shown generally at 20, a worm 22, a worm gear 24, and an operator arm 26.
Power and control lines (not shown) are suitably connected to the motor 18. Preferably, such lines extend from the motor 18 to the jamb 14 in any suitable manner. For example, the lines can be secured along the operator arm 26.
The gear reducing train 20 generally includes first through sixth gears 27-32. Each of the first through sixth gears 27-32 has a large diameter portion and small diameter portion. The large diameter portion of each gear is generally indicated with the suffix "a", and the small diameter portion of each gear is generally indicated with the suffix "b". The motor 18 drives a drive shaft 34, which has a drive shaft gear 36 operably secured to its end.
The drive shaft gear 36 engages the large diameter portion 27a of first gear 27. The small diameter portion 27b of first gear 27 engages the large diameter portion 28a of second gear 28. The small diameter portion 28b of second gear 28 engages the large diameter portion 29a of third gear 29. The small diameter portion 29b of third gear 29 engages the large diameter portion 30a of fourth gear 30. The small diameter portion 30b of fourth gear 30 engages the large diameter portion 31a of fifth gear 31. The small diameter portion 31b of fifth gear 31 engages the large diameter portion 32a of sixth gear 32. The small diameter portion 32b of sixth gear 32 is operably secured to worm 22. In the FIG. 2 embodiment, the first 27, second 29 and third 31 gears all rotate about a first axis 38, while the second 28, fourth 30 and sixth 32 gears, and the worm 22 all rotate about a second axis 40, which is spaced apart from and generally parallel to the first axis 38.
It should thus be appreciated that the disclosed gear reduction structure is a preferred structure which will permit use of a small, low-power, inexpensive motor 18 despite the large loads which are often encountered during opening and closing of the window sash 12, whether to overcome wind loads (particularly on large window sashes) or to create a weather strip seal when closing against the jamb 14 or to break the seal when initially opening.
The worm 22 engages the worm gear 24, rotating worm gear 24 about a generally vertical axis. A shaft 42 extends through the center of the worm gear 24 and is fixedly secured to one end of operator arm 26 so that the worm gear 24 and operator arm 26 pivot together. The other end of operator arm 26 is suitably secured to the jamb 14 to cooperate with the hinge 16 at the top of the sash 12 so that the sash 12 will open and close relative to the jamb 14 in response to pivoting of the operator arm 26.
For example, if a standard casement hinge typically has a sash arm secured along the sash 12, with one end pivotally secured to a shoe which is slidable along a track secured to the window jamb 14, and a support arm pivotally secured at one end to the jamb 14 and pivotally secured at the other end relative to the sash (typically pivotally connected directly to the sash arm). If the hinge 16 is such a standard casement hinge, the operator arm 26 would preferably be pivotally secured to the jamb 14 in a suitable manner, as by the pivot 44 and bracket 46 shown in FIG. 2. With such a configuration, a track 47 would preferably be secured to the jamb 14 (similar to the track of the hinge 16) and support a sliding shoe 48 thereon, with a sash arm 49 (shown broken away in FIG. 2) pivotally secured to the shoe 48 and suitably secured to the sash 12.
Operation of the FIG. 2 embodiment is as follows.
When the motor 18 is activated to open the window sash 12 from the jamb 14, the motor will cause drive shaft 34, and hence drive shaft gear 36 which is secured thereto, to rotate in a first direction. The gear reducing train 20 is responsive to the rotation of the drive shaft gear 36 and causes the worm 22 to rotate at a reduced rate with respect to drive shaft gear 36. Rotation of the worm 22 about the second axis 40 causes the worm gear 24 to rotate which in turn pivots the secured operator arm 26. Due to the geometry of the hinge 16 and the operator 10, pivoting of the operator arm 26 relative to the sash 12 will cause the sash 12 to move relative to the jamb 14, with the operator arm 26 pivoting relative to the jamb 14 about pivot 44, and the sash arm 49 in turn pivoting about the shoe 48 which slides along the track 47.
In the embodiment shown in FIG. 2, when the motor 18 is rotated in the direction opposite the first direction, the driving force will pivot the worm gear 24 and operator arm 26 in the opposite direction toward closing the sash 12 against the jamb 14.
It should be noted that the exact number and placement of gears 27-32 comprising the gear reducing train 20 is not imperative to the power window operator 10 of the present invention. Various numbers of gears, gear sizes and gear configurations can be implemented in the gear reducing train 20 without departing from the spirit and scope of the present invention. These variations will obviously depend many factors, including the size and shape of the window to be operably opened and closed, as well as the motor operation and the desired speed of moving the sash 12.
A second preferred embodiment of the present invention is shown in FIGS. 3-5. For ease of reference, components similar to components previously described in the embodiment of FIGS. 1-2 are designated with similar reference numerals, though with a "prime" added.
FIGS. 3-5 show an a different power window operator 10' embodying the present invention. The operator 10' is ideally suited for use with a standard casement hinge such as previously described, as the worm gear 24' may be centrally located relative to the thickness of the sash 12' as best shown in FIG. 5, and therefore the sash arm 49' (see FIG. 5) may be readily aligned with the pivotal connection of the operator arm 26' to the sash 12', as is standard with casement hinges. As such, the operator 10' may be readily used in combination with a standard hinge on the top of the sash 12'.
As with the FIGS. 1-2 embodiment, power and control lines (not shown) are suitably connected to the motor 18. Preferably, such lines extend from the motor 18 to the jamb 14 in any suitable manner. For example, the lines can be secured along the operator arm 26'.
Referring to FIG. 3, the internal components of the window operator 10' are mounted inside a housing 52. Housing 52 includes sidewalls 56, 57, end walls 58, 59, and a closure wall 55 connecting the end walls 58, 59 and the sidewalls 56, 57. Housing 52 further includes a second closure wall 53 generally conforming to the shape of the bottom surface of the sash 12'. Second closure wall 53 connects the end walls 58,59 and the sidewalls 56,57 opposite closure wall 55. The housing 52 is disposable in a generally box-shaped cavity defined in one side of the sash 12'.
In a preferred embodiment, the housing 52 has finger-joints 54 (best seen in FIG. 4) on end walls 58, 59 which engage matching finger-joints on opposite sides of the sash cavity, and may be suitably secured to the sash cavity by, for example, an appropriate glue or adhesive (depending on the materials of the sash 12' and the housing 52).
It should be understood that though the above described housing is a preferred embodiment, in some installations the sash 12' may be big enough, or the below described components of the operator 10' small enough, so that the housing may be enclosed in a cavity with some of the walls being defined by parts of the sash 12'. Any such structure would be suitable so long as, in the preferred form, the outer surface would integrally conform with the basic outer surface of the sash surrounding the cavity.
In a preferred embodiment, the housing 52 is made of a thermally non-conductive material. Further, while the housing 52 herein is generally described for use with a power window operator 10', it should be recognized that the housing 52 could be implemented as an integral mounting structure for mounting any of a variety of window operating systems, including but not limited to, a power window lock.
The housing 52 is partially removed in FIG. 4 to show the internal components of the power window operator 10'. The power window operator 10' generally includes a motor 18 having a drive shaft 34 attached to a drive shaft gear 36', a gear reducing train shown generally at 20', a worm 22', a worm gear 24', and an operator arm 26' (shown in FIGS. 3 and 5). The gear reducing train 20' generally includes first through third gears 27'-29'. As best shown in FIG. 5, each of the first through third gears 27'-29' has a large diameter portion and a small diameter portion. The large diameter portion of each gear is generally indicated with the suffix "a", and the small diameter portion of each gear is generally indicated with the suffix "b".
The drive shaft gear 36' engages the large diameter portion 27a' of first gear 27'. The small diameter portion 27b' of first gear 27' engages the large diameter portion 28a' of second gear 28'. The small diameter portion 28b' of second gear 28' engages the large diameter portion 29a' of third gear 29'. The small diameter portion 29b' of third gear 29' is operably connected to worm 22' through a gear 66 having a diameter generally larger than the diameter of the worm 22' and located at a distal end of worm 22'. Gear 66 may be formed integral with worm 22' or fixedly secured to the distal end thereof. Gear 66 engages the small diameter portion 29b' of third gear 29' and rotates the worm 22' at the same rotational speed as gear 66. The worm 22' engages worm gear 24', rotating worm gear 24' about an axis generally perpendicular to the axis of the motor 18.
Again, the exact number and placement of gears 27'-29' comprising the gear reducing train 20' is not imperative to the power window operator 10' of the present invention. Various numbers of gears, gear sizes and configurations can be implemented in the gear reducing train 20' without departing from the spirit and scope of the present invention.
A cylindrical collar 68 extends through the center of worm gear 24'. The cylindrical collar 68 includes a bottom portion having outwardly projecting clutch teeth 70 which engage a cooperating set of inwardly projecting teeth 72 in a central opening in the worm gear 24' when the collar 68 and worm gear 24' are axially aligned.
The collar 68 also has an upper portion 88 having a set of axially spaced teeth 80 basically forming a rack. Although it will become apparent hereafter that the teeth 80 actually need to be on only one side of the collar 68, in the preferred embodiment the teeth 80 extend around the collar upper portion 88 to ease in assembly (as this allows the collar 68 to be assembled in any angular position).
A spline shaft 74 extends through both the cylindrical collar 68 and the worm gear 24' and is suitably mounted to the housing 52 and/or sash 12' for pivoting about the same vertical axis as the worm gear 24'. The spline shaft 74 is also suitable fixed to a distal end of the operator arm 26' so that the shaft 74 and arm 26' pivot together. The spline shaft 74 includes outwardly extending clutch teeth 76 extending along its length, which teeth 76 engage a mating set of inwardly extending teeth 78 on an inner surface of cylindrical collar 68 to secure the collar 68 and shaft 74 for pivoting together.
Operation of the embodiment shown in FIGS. 3-5 is similar to the operation of the embodiment in FIGS. 1-2.
Specifically, when the motor 18 is activated to open the sash 12' from the jamb 14, the motor 18 turns the drive shaft 34 and drive shaft gear 36' in a first direction. The gear reducing train 20' is responsive to the rotation of the drive shaft gear 36' and causes the worm 22' to rotate at a reduced gear ratio with respect to the drive shaft gear 36'. In one preferred embodiment, for example, the gear reducing train 20' achieves a reduction ratio of approximately 750:1 (with such a reduction rate permitting use of a small, low-power, inexpensive motor 18 despite the large loads which are often encountered during opening and closing of the window sash 12' as previously described).
Rotation of the worm 22' causes the worm gear 24' to pivot, which in turn pivots the cylindrical collar 68, which in turn pivots the spline shaft 74, which in turn pivots the operator arm 26' to open or close the sash 12' from or against the jamb 14 depending on the direction of pivoting of the spline shaft 74. That is, when the worm gear 24' pivots in a clockwise direction as viewed in FIG. 5, the sash 12' is closed toward the jamb 14, while counter-clockwise pivoting of the worm gear 24' opens the sash 12' away from the jamb 14.
FIG. 4 also shows a clutch mechanism indicated generally at 90 which cooperates with the previously described cylindrical collar 68 to permit the operator arm 26' to be disengaged from the gear reducing train 20' to free the sash 12' for manual opening and/or closing such as might be desirable, for example, in the event of a power outage. That is, since the worm 22' effectively prevents backdrive to prevent the sash 12' from being moved except through pivoting of the drive train and worm 22', the clutch mechanism 90 disengages the operator 10' from the worm 22' to permit movement of the sash 12' even though the worm 22' is not rotated
The clutch mechanism 90 includes a control gear 82 rotatably mounted in the housing 52 and engaging the axially spaced teeth 80 of the cylindrical collar 68 An actuator gear 84 is also mounted in the housing so as to engage the control gear 82, with a handle 86 operably secured to the actuator gear 84 and projecting from the housing 52 (see FIG. 3) to permit manual pivoting of the handle 86.
As generally viewed in FIG. 4, clockwise pivoting of the handle 86 causes the actuator gear 84 to also rotate in a clockwise direction. This causes the control gear 82 to rotate in a counter-clockwise direction and, though its engagement with the collar axially spaced teeth 80, slides the cylindrical collar 68 upwardly on the spline shaft 74 sufficiently to disengage the clutch teeth 70 on the bottom portion of cylindrical collar 68 from the clutch teeth 72 on the inner surface of worm gear 24'. Accordingly, the spline shaft 74 and connected operator arm 26' may pivot independently of the worm gear 24' to permit manual moving of the sash independent of the motor 18, drive train, worm 22' and worm gear 24'.
It should thus be apparent that operators made according to the present invention may be readily integrated into the design of the window without detracting from the beauty of the window, and may be used even in retrofit installations without intruding into the desired visual opening of the window. Retrofitting, in fact, may be easily accomplished by simply adding a new sash incorporating the invention of the present invention, with only minimal modifications required of the existing construction to accommodate power and control cables. In this regard, the integrated design of the operator also will not interfere with the maintenance of the window unit, such as painting, nor will it adversely affect the strength of the window unit over time.
It should also be apparent that operators made according to the present invention may be made at relatively low cost despite the small space within which the drive components must be fit, since the operator allow for the use of low-power and therefore inexpensive motors while still maintaining the desired driving power and speed.
It should further be apparent that operators made according to the present invention will operate at low noise levels within the building. Not only is the motor completely enclosed in a housing to deaden sounds, but the motor is also located in the sash at a point which maximally spaced from the building interior. Moreover, through most of the sash's range of motion, the motor is actually disposed outside the building so that much of whatever noise does escape the housing will disperse outside the building.
Still other aspects, objects and advantages of the present invention can be obtained from a study of the specification, the drawings and the appended claims. | An assembly for opening and closing a window sash from and against a window frame including a motor mounted to a window sash and having an output drive shaft, an operator arm having one portion pivotally connected to the sash and a second portion operably connected to the frame, and a drive train operably connecting the motor drive shaft to the output arm for controlling pivotal movement thereof in relation to the sash. A clutch mechanism permits the operator arm to be selectively disconnected from the drive train to allow the sash to be manually opened. A housing, disposable in a cavity defined in a generally rectangular box shape on a sash side, encloses the motor, drive train, and clutch mechanism. The housing has finger-jointed ends which are adhesively bonded to matching finger-joints formed on opposite sides of the sash cavity. | 4 |
FIELD OF THE INVENTION
The present invention relates to a method of and apparatus for providing navigation and other information to a user; and more particularly, the present invention relates to such a method and apparatus wherein the information provided to the user is generated based on differing data sources. Still more particularly, the present invention relates to a method and apparatus whereby a navigation device is connectable to a user device for interacting with a user.
BACKGROUND
There are two main types of vehicle navigation systems currently in use.
The first type of system includes a navigation-capable device, e.g. a GPS-based device, located in a vehicle which performs all required computations and contains all necessary navigation data. In this system, the navigation functions are restricted to the vehicle and can be performed anywhere in an area covered by navigation data stored in the device. A device according to this type of system requires a large amount of computational power, memory, and a large amount of map data storage.
Disadvantageously, there is no way to easily update frequently changing information, i.e. transitory information, stored in the system, e.g. restaurant names, traffic conditions/road conditions, construction projects, etc. Current in-vehicle navigation systems allow traffic information update using radio link information about traffic conditions at predetermined locations. Disadvantageously, this time critical information is not reconfigurable on-the-fly, the traffic information is only available for the predetermined points at the time of map creation. If the transitive information is stored in the system, data stored in data storage on the system requires complete replacement or update of the data. If only a small portion of the data changes or if the changes are frequent in nature, the replace/update process becomes tedious to a user. Further, if the user fails to update just prior to leaving for a destination and traffic conditions change, the user may be frustrated to encounter significant traffic delays.
The second type of system includes data and computational power hosted remote from the device. Smaller local maps and routing directions are then provided to the device over a network connection, e.g. a cellular telephone network, a system employing this type of architecture requires a powerful central server to perform route computation and a central database collocated with the server for storing map data. Disadvantageously, navigation capability, e.g. GPS, is required at the user device which further must be able to perform map matching or route following to display turn instructions at the correct time. Under this system, the primary objective is to move the additional cost and complexity required to perform navigation and store map data from a user device, e.g. a personal digital assistant (PDA) or a cellular telephone, to a central server. This trade-off allows for a simpler user device; however, transmission of server generated maps and routing increases the cost and bandwidth required.
Several additional disadvantages of such an approach include:
The cellular phone still requires the additional cost of a GPS or other navigational capability and must be capable of performing maps matching and route following computations;
Network capabilities and communication bandwidth can become swamped or overwhelmed if a large number of users require routing services at the same time, e.g. multiple requests from users for rerouting during rush-hour traffic; and
The cellular phone must be in constant contact with the server in order to receive updated directions and information.
Based on the foregoing discussion, there is a need in the art for a third type of system able to perform complex computations, e.g. maps matching and route following, and store large amounts of maps data without being tied to a specific installation location and able to receive updates and other navigation information without requiring constant connection time and high bandwidth.
SUMMARY
It is therefore an object of the present invention to provide an improved navigation system able to provide navigation information, store map data, and receive updated information.
Another object of the present invention is to provide a portable navigation system providing navigation information without requiring constant connection time and high bandwidth.
A navigation system for providing navigation information to a user responsive to user commands includes (1) a user device for issuing user commands and displaying a user interface to the user and (2) a navigation device for connecting to the user device and receiving user commands from the user device and transmitting navigation information to the user device. The information received from the user device includes updated map information, traffic information, news information, weather information, event-related information, business-related information, and user-specified information. The navigation device performs route following based on commands received from the user device and transmits routing instructions to the user device. The navigation device and user device are separately operable by a user.
An apparatus aspect for providing navigation information to a user device responsive to commands received from the user device includes a navigation device adapted to be connected to the user device and receiving commands from the user device and transmitting navigation information to the user device. In a further embodiment, the user device receives information and transmits the information to the navigation device for combination with the navigation information. The user device received information includes transitory information such as updated map information, traffic information, news information, weather information, event-related information, business related information, and user-specified information.
Another apparatus aspect includes a navigation system for providing navigation information to a user responsive to user commands. The navigation system includes a user device for issuing user commands and displaying a user interface to the user and a navigation device connectable to the user device and able to receive user commands from the user device and transmit navigation information to the user device.
A method aspect of using a navigation system including a user device and a navigation device adapted to be connected to the user device includes establishing a connection between the navigation device and the user device. Navigation signals are received at the navigation device for determining the navigation system position. The user device is manipulated to command the navigation device to provide navigation information to the user device using the established connection. Responsive to commands received from the user device, the navigation device transmits navigation information to the user device using the established connection.
Still other objects and advantages of the present invention will become readily apparent to those skilled in the art from the following detailed description, wherein the preferred embodiments of the invention are shown and described, simply by way of illustration of the best mode contemplated of 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 is illustrated by way of example, and not by limitation, in the figures of the accompanying drawings, wherein elements having the same reference numeral designations represent like elements throughout and wherein:
FIG. 1 is a high-level block diagram of a navigation system according to an embodiment of the present invention;
FIG. 2 is a high-level block diagram of a computer system on which a navigation device of the navigation system of FIG. 1 may be implemented according to an embodiment of the present invention;
FIG. 3 is a high-level block diagram of a computer system on which a user device of the navigation system of FIG. 1 may be implemented according to an embodiment of the present invention; and
FIG. 4 is a high-level block diagram of processes executed by an embodiment of the present invention in operation.
DETAILED DESCRIPTION
Recent developments in the field of computers, and more specifically in the areas of low-cost memory and increased processing capability, have enabled the creation of an additional system architecture for using a navigation device 102 ( FIG. 1 ), e.g. a GPS receiver, in conjunction with a user device 104 ( FIG. 1 ), e.g. a cellular telephone or a PDA, as part of a navigation system 100 ( FIG. 1 ). Navigation Device 102 can also use sensors other than GPS, such as a magnetometer and accelerometer together with GPS for better map matching and position determination.
The computational processing required of the central server of the above-described system is now able to be made part of a low-cost navigation device capable of computing maps, performing routing, and other computation tasks necessary for vehicle and/or individual user routing. The navigation device 102 is further able to perform map matching and route following computations and provide this information to the connected user device 104 .
In such a configuration, the user device 104 , e.g. cellular telephone or PDA, is used only for interacting with the user, such as acting as a display or user interface terminal. As described below, navigation and other information and user commands may be transmitted between the navigation device 102 and the user device 104 via many different communication connections, e.g. short-range high-speed communication links such as serial connections or wireless connections, such as Bluetooth wireless technology or similar technologies. The user communicates with the navigation device 102 via the user device 104 or additional user interface devices, e.g. keyboard, keypad, and/or speech recognition capabilities.
There are several advantages of the above described system:
A user device can be used as a navigation system without requiring additional processing capability and storage on the user device;
The navigation device is not required to include the sometimes significant cost of the user interface system, e.g. requisite hardware and software capabilities;
Because the user device is connected between the navigation device and an information server, both local (navigation device-generated) and network (information server-generated) routing can be used depending on user preferences and/or data characteristics, e.g. freshness of data; and
Route navigation can be performed in areas where the user device is unable to connect to the information server.
A high-level block diagram of the navigation system 100 according to an embodiment of the present invention is depicted in FIG. 1 . Navigation system 100 includes two components capable of communicating with each other: a navigation device 102 and a user device 104 . Navigation system 100 communicates with (1) a navigation aid server 106 using the navigation communication link 108 and (2) an information server 110 using an information communication link 112 . Navigation device 102 and user device 104 communicate over a device communication link 114 . A third communication device (not shown) connecting the user device 104 with a remote server, e.g. an information server 110 , for obtaining time-sensitive routing and point-of-interest information on the time scale of the navigation device map update may be employed in a specific embodiment; however, it is to be understood that the user device includes the third communication device.
Navigation aid server 106 in a particular embodiment is a GPS satellite or pseudolite as is known in the art and navigation communication link 108 is a GPS signal broadcast by the GPS satellite or pseudolite. Depending on the location and configuration of navigation system 100 , the navigation system may be in communication with more than one navigation aid server 106 via one or more navigation communication links 108 . It is to be understood that although there may be more than one navigation aid server 106 , for simplicity of explanation only a single navigation aid server will be discussed herein. It is to be further understood that although a GPS-based system is described, other navigation aid servers and navigation information providing servers may be used in conjunction with the present invention without departing from the spirit and scope of the invention. Further, although navigation communication link 108 is described herein as being a wireless connection, it is to be understood that a wired connection may be used in addition to or in place of a wireless connection.
Information server 110 in a particular embodiment is a wireless or cellular-based information providing computer system capable of communication with navigation system 100 over information communication link 112 , e.g. a wireless application protocol (WAP)-based cellular telephone network connection. It will be understood by persons skilled in the art that navigation system 100 may be in communication with more than one information server 110 over more than one information communication link 112 . Further, although information communication link 112 is described herein as being a wireless connection, it is to be understood that a wired connection may be used in addition to or in place of a wireless connection.
Information server 110 is able to provide frequently changing, i.e. transitory, information such as weather information, traffic information, news, etc. In a further detailed embodiment, information server 110 is able to provide area-wide business and/or user-defined interest information, e.g. restaurant specials, shopping sales, or cultural event information. For example, the user may manipulate user device 104 to specify information to be obtained from information server 110 , e.g. to determine what current events are planned in a particular city in the next 24 hours. Depending on the bandwidth available and cost to the user, information communication link 112 may further be used to obtain updated map data and routing information.
Depending on the location and configuration of navigation system 100 , the navigation system may be in communication with more than one information server 110 via one or more information communication links 112 . It is to be understood that although there may be more than one information server 110 , for simplicity of explanation only a single information server will be discussed herein. It is to be further understood that although a WAP-based system is described, other information servers and information providing servers may be used in conjunction with the present invention without departing from the spirit and scope of the invention. Further, although information communication link 112 is described herein as being a wireless connection, it is to be understood that a wired connection may be used in addition to or in place of a wireless connection.
Navigation device 102 includes a computer system which, based on signals received from navigation aid server 106 via a navigation interface 216 using navigation communication link 108 , is able to determine device 102 position with reference to navigation aid server 106 , as is known to persons skilled in the art. Navigation device 102 includes (1) a navigation processor 116 for determining position of device 102 and performing other navigation functions, e.g. map matching and route following calculations, and (2) a data storage unit 118 for storing map data, route data, position data, and other variables and information. Optionally, in a particular embodiment navigation device 102 may include a user interface 120 (dashed line) for displaying information to and receiving commands from a user.
A high-level block diagram of a computer system on which an embodiment of navigation device 102 may be implemented is depicted in FIG. 2 . Navigation device 102 includes a bus 202 or other communication mechanism for communicating information, and a processor 116 coupled with the bus 202 for processing information. Navigation device 102 also includes a main memory 206 , such as a random access memory (RAM) or other dynamic storage device, coupled to the bus 202 for storing navigation information, e.g. map data, and transitory information obtained from user device 104 , e.g. traffic information, according to an embodiment of the present invention and instructions to be executed by processor 116 . The navigation information includes information that does not change as often as the transitory information, e.g. changes occur once every six months, a year, or greater. Typical navigation information includes topographic information, geographic information, and roadway or route information. Main memory 206 also may be used for storing temporary variables or other intermediate information during execution of instructions to be executed by processor 116 . Navigation device 102 further includes a read only memory (ROM) 208 or other static storage device coupled to the bus 202 for storing static information and instructions for the processor 116 . A data storage unit 118 , such as a magnetic disk, optical disk, or other storage device, e.g. compact flash, smart media, or other storage device, is optionally provided and coupled to the bus 202 for storing instructions, navigation information, and transitory information. Additional stored information can include acceleration, temperature, pressure, and information from magneto sensors in order to assist the navigation device 102 , e.g. GPS, in map matching and position determination.
Navigation device 102 may be coupled via the bus 202 to a display 212 , such as a flat panel touch-sensitive display connected as an integral piece of the navigation device, for displaying an interface to a user. An optional input device 214 (dash dot line), such as a keyboard including alphanumeric and function keys and/or a cursor control, is optionally coupled to the bus 202 for communicating information and command selections to the processor 116 . As is known in the art, cursor control may include devices such as a stylus, pen, mouse, a trackball, or cursor direction keys for communicating direction information and command selections to processor 116 and for controlling cursor movement on the display 212 . This type of input device typically has two degrees of freedom in two axes, a first axis (e.g., x) and a second axis (e.g., y) allowing the device to specify positions in a plane.
The invention is related to the use of navigation device 102 , such as the depicted computer system of FIG. 2 , to store and access data, e.g. navigation information and transitory information. According to one embodiment of the invention, data is stored and accessed by navigation device 102 in response to processor 116 executing sequences of instructions contained in main memory 206 in response to input received via input device 214 or a communication interface 218 using communication link 114 . Such instructions may be read into main memory 206 from another computer-readable medium, such as data storage unit 118 . A user interacts with the data via either a user interface 120 displayed on display 212 of navigation device 102 or via a user interface 122 displayed on user device 104 described in detail below.
However, the computer-readable medium is not limited to devices such as data storage unit 118 . For example, the computer-readable medium may include a floppy disk, a flexible disk, hard disk, magnetic tape, or any other magnetic medium, a compact disc-read only memory (CD-ROM), any other optical medium, punch cards, paper tape, any other physical medium with patterns of holes, a random access memory (RAM), a programmable read only memory (PROM), an erasable PROM (EPROM), a Flash-EPROM, any other memory chip or cartridge, a carrier wave embodied in an electrical, electromagnetic, infrared, or optical signal, or any other medium from which a computer can read. Execution of the sequences of instructions contained in the main memory 206 causes the processor 116 to perform the process steps described below. In alternative embodiments, hard-wired circuitry may be used in place of or in combination with computer software instructions to implement the invention. Thus, embodiments of the invention are not limited to any specific combination of hardware circuitry and software.
Navigation device 102 also includes a communication interface 218 coupled to the bus 202 and providing two-way data communication using communication link 114 as is known in the art. For example, communication interface 218 may be a wired or wireless interface connection to provide a data communication connection between navigation device 102 and user device 104 . As another example, communication interface 218 may be a local area network (LAN) card to provide a data communication connection to a compatible LAN. Wireless links may also be implemented. In any such implementation, communication interface 218 sends and receives electrical, electromagnetic or optical signals which carry digital data streams representing various types of information. Of particular note, the communications through interface 218 may permit transmission or receipt of instructions and data to be stored and accessed.
Navigation device 102 can send messages and receive data, including program code, through communication interface 218 using communication link 114 with user device 104 . The received code may be executed by processor 116 as it is received, and/or stored in data storage unit 118 , or other non-volatile storage for later execution. In this manner, navigation device 102 may obtain application code, navigation information, and transitory information in the form of a carrier wave.
User device 104 , e.g. a cellular telephone or a PDA, is a communication and/or information device usable by the user to receive: (1) information from information server 110 via an information communication interface using information communication link 112 and (2) navigation information from navigation device 102 via a communication interface 316 using device communication link 114 . Further, user device 104 is usable by a user to command navigation device 102 and to request information from information server 110 . User device 104 is typically small, lightweight and portable, and able to be easily carried on the person. As is known in the art, user device 104 includes a processor 304 and a memory 306 ( FIG. 3 ) enabling processing and storage of information, respectively.
A high-level block diagram of a user device including a computer system on which an embodiment of user device 104 may be implemented is depicted in FIG. 3 .
FIG. 3 is a block diagram illustrating an exemplary computer or user device 104 , e.g. a handheld device such as a portable telephone or PDA, upon which an embodiment of the invention may be implemented. The present invention is usable with currently available handheld and embedded devices, and is also applicable to personal computers and the like.
User device 104 includes a bus 302 or other communication mechanism for communicating information, and a processor 304 coupled with the bus 302 for processing information. User device 104 also includes a main memory 306 , such as a random access memory (RAM) or other dynamic storage device, coupled to the bus 302 for storing user information and transitory information according to an embodiment of the present invention and instructions to be executed by processor 304 . Main memory 306 also may be used for storing temporary variables or other intermediate information during execution of instructions to be executed by processor 304 . User device 104 further includes a read only memory (ROM) 308 or other static storage device coupled to the bus 302 for storing static information and instructions for the processor 304 . A storage device 310 (dotted line), such as a compact flash, smart media, or other storage device, is optionally provided and coupled to the bus 302 for storing instructions.
User device 104 may be coupled via the bus 302 to an optional display 312 for displaying a user interface 122 to a user. In order to reduce space requirements for handheld devices, the display 312 typically includes the ability to receive input from an input device 314 , such as a stylus, in the form of user manipulation of the input device 314 on a sensing surface of the display 312 . Optionally, input device 314 (dash dot line), such as a keyboard including alphanumeric and function keys, is optionally coupled directly to the bus 302 for communicating information and command selections to the processor 304 . User input device 314 may include a cursor control, such as a stylus, pen, mouse, a trackball, or cursor direction keys for communicating direction information and command selections to processor 304 and for controlling cursor movement on the display 312 . The input device 314 typically has two degrees of freedom in two axes, a first axis (e.g., x) and a second axis (e.g., y) allowing the device to specify positions in a plane.
The invention is related to the use of user device 104 , such as the depicted computer of FIG. 3 , to present navigation information to a user. According to one embodiment of the invention, data is stored and accessed from an information server 110 and navigation device 102 by user device 104 in response to processor 304 executing sequences of instructions contained in main memory 306 in response to input received via display 312 . Such instructions may be read into main memory 306 from another computer-readable medium, such as optional storage device 310 . A user interacts with the user device 104 by the user interface 122 displayed on display 312 .
However, the computer-readable medium is not limited to devices such as optional storage device 310 . For example, the computer-readable medium may include a floppy disk, a flexible disk, hard disk, magnetic tape, or any other magnetic medium, a compact disc-read only memory (CD-ROM), any other optical medium, punch cards, paper tape, any other physical medium with patterns of holes, a random access memory (RAM), a programmable read only memory (PROM), an erasable PROM (EPROM), a Flash-EPROM, any other memory chip or cartridge, a carrier wave embodied in an electrical, electromagnetic, infrared, or optical signal, or any other medium from which a computer can read. Execution of the sequences of instructions contained in the main memory 306 causes the processor 304 to perform the process steps described below. In alternative embodiments, hard-wired circuitry may be used in place of or in combination with computer software instructions to implement the invention. Thus, embodiments of the invention are not limited to any specific combination of hardware circuitry and software.
User device 104 also includes a communication interface 316 coupled to the bus 302 and providing two-way data communication using device communication link 114 as is known in the art. For example, communication interface 316 may be a wired or wireless connection to provide a data communication connection between navigation device 102 and user device 104 . As another example, communication interface 316 may be a local area network (LAN) card to provide a data communication connection to a compatible LAN. Wireless links may also be implemented. In any such implementation, communication interface 316 sends and receives electrical, electromagnetic or optical signals which carry digital data streams representing various types of information. Of particular note, the communications through interface 316 may permit transmission or receipt of instructions and data to be stored and accessed.
User device 104 further includes a information communication interface 318 coupled to the bus 302 and providing two-way data communication using information communication link 112 as is known in the art. For example, information communication interface 318 may be a wired or wireless connection to provide a data communication connection between user device 104 and information server 110 . Wireless links may also be implemented. In any such implementation, information communication interface 318 sends and receives electrical, electromagnetic or optical signals which carry digital data streams representing various types of information. Of particular note, the communications through interface 318 may permit transmission or receipt of instructions and data to be stored and accessed.
Device communication link 114 may be either a wireless or wired connection. In one particular embodiment, device communication link 114 is a radio frequency (RF) wireless communication link using the Bluetooth protocol for communication between navigation device 102 and user device 104 . In another particular embodiment, device communication link 114 is a serial, wired communication link using a serial protocol for communication between navigation device 102 and user device 104 .
A description of the operation of an embodiment of the present invention is now provided with reference to a high level function diagram depicted in FIG. 4 . In process step 400 , a user places a user device 104 connected to or proximate to a navigation device 102 such that a device communication link 114 is established between the user device and the navigation device. The combined user device and navigation device make up a navigation system 100 as shown in FIG. 1 and described in detail above.
The next step in user operation of navigation system 100 is step 402 wherein user input at user device 104 is communicated to navigation device 102 and navigation information is communicated from navigation device 102 to user device 104 and displayed to the user. Step 402 includes five additional processes 403 – 407 for providing different functionality to the user. Process 403 , executed by navigation processor 116 , uses navigation signals received via navigation communication link 108 to determine the current position of the navigation system 100 .
Process 404 , executed by navigation processor 116 , accesses navigation information stored in memory 206 or optionally data storage unit 118 to determine the position of a user designated destination. Further, in a particular embodiment, the position information for a user destination may be obtainable from transitory information available from information server 110 via information communication interface 318 of user device 104 . For example, a new restaurant, weather information, or a current event not stored in memory 206 may be found in memory 306 of user device 104 based on transitory information obtained from an information server 110 according to a below described process 405 .
Process 405 , executed by processor 304 of user device 104 , uses information communication interface 318 of user device 104 to communicate with information server 110 to obtain transitory information. The obtained transitory information includes navigation and other information which changes on a more frequent basis than the navigation information stored in navigation device 102 . For example, traffic information, current event information, and other hourly, daily, weekly, or monthly changing information. Typically, a large amount of transitory information changes frequently, e.g. every day, preventing the constant update of the stored information in navigation system 100 .
Process 406 , executed by navigation processor 116 , uses navigation information from navigation device 102 and transitory information from user device 104 to determine a route from the current system position (process 403 ) to the destination (process 404 ). Routes may be determined based on different criteria, e.g. shortest distance, fastest time, mostly highway travel, mostly surface street travel.
Process 407 , executed by navigation processor 116 , uses the route output from process 406 and an updated determination of current system position (process 403 ) to provide instructions to the user indicating the route to follow to reach the destination identified in process 404 . While following the route (process 407 ), additional updated transitory information may be obtained in order to modify the route being used to reach a destination.
In process 408 , the navigation device and the user device are separated removing the device communication link 114 . User device 104 is then usable as a user device, e.g. a telephone or PDA, and navigation device 102 is usable as a navigation device, e.g. a GPS receiver.
It will be readily seen by one of ordinary skill in the art that the present invention fulfills all of the objects set forth above. After reading the foregoing specification, one of ordinary skill will be able to affect various changes, substitutions of equivalents and various other aspects of the invention as broadly disclosed herein. It is therefore intended that the protection granted hereon be limited only by the definition contained in the appended claims and equivalents thereof. | A navigation system for providing navigation information to a user responsive to user commands includes (1) a user device for issuing user commands and displaying a user interface to the user and (2) a navigation device for connecting to the user device and receiving user commands from the user device and transmitting navigation information to the user device. The information received from the user device includes updated map information, traffic information, news information, weather information, event-related information, business-related information, and user-specified information. The navigation device performs route following based on commands received from the user device and transmits routing instructions to the user device. The navigation device and user device are separately operable by a user. | 6 |
BACKGROUND OF THE INVENTION
[0001] Six-pack or multiple bottle carriers which hold bottles or containers by their necks to allow them to be carried are well known. The bottles typically have labels to advertise their contents. A common type of commercially available prior art carrier is fabricated from thin gauge sheets of plastic. The thin planar sheet is die-cut to provide holes for engaging the necks of the containers and holes for grasping the carrier, and is thermo-formed into a three dimensional shape to provide structural integrity to the carrier. There are several problems with this carrier. First, the thermo-formed plastic sheet shrouds the container, obscuring visibility of the product and product labels. Second, the thin gauge of the plastic material makes the carrier uncomfortable to carry. Further, the thin gauge material requires a substantial amount of structural surface area to support the containers. This tends to further hide the product in the containers and advertising on the labels.
[0002] Another carrier design is disclosed in U.S. Pat. No. 3,633,962. It has keyhole-shaped neck retainers and sharp edges on both the neck retainers and the finger holes. This carrier is also uncomfortable to carry due to its sharp edges. In addition, the rigid keyhole-shaped neck retainers are difficult to fit over the neck flanges of the containers, and likewise it is difficult to remove the containers from the carrier due to the rigid key hole-shaped neck retainers.
[0003] Commonly owned U.S. Pat. No. 6,129,397 discloses a six pack carrier design that overcomes the aforementioned drawbacks of the prior art. However, that carrier design allows the outboard containers to sag a bit due to inadequate support for them when the loaded carrier is lifted by the carrier's handholds.
[0004] What is needed is a carrier that is comfortable to carry, allows for excellent visibility of the product in the containers and the labels on the containers, allows for easy application and removal of the containers from the carrier, and provides good balance in carrying and handling containers.
BRIEF SUMMARY OF THE INVENTION
[0005] There are essentially two aspects to the present invention, both of which comprise an integrally-molded carrier for carrying multiple containers by their necks by grasping a pair of opposing finger loops.
[0006] In a first aspect, the carrier has a substantially planar web defining a pair of centrally located annular support openings. Each support opening has a finger loop disposed therein with the two finger loops in substantial mirrored alignment. Each finger loop is attached to the annular opening at two points tangent to the two outermost container neck-engaging structures. The carrier has a plurality of annular neck-engaging structures integral with the web and arranged around the periphery of the support openings. Each of the neck-engaging structures has a respective circumferential rib and a plurality of flanges projecting inwardly from the circumferential rib for releasably engaging the necks of the containers.
[0007] In a second aspect, there is provided a plurality of the same type of neck-engaging structures as noted above, the neck-engaging structures being secured together by smaller gap-bridging elements and having a pair of centrally disposed larger gaps that accommodate a pair of finger loops in substantial mirrored alignment.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0008] FIG. 1 is a perspective view of an exemplary carrier of the invention.
[0009] FIG. 2 is a plan view of the carrier of FIG. 1 .
[0010] FIG. 3 is a side view of the carrier of FIG. 1 shown in place on multiple containers.
[0011] FIG. 4 is a perspective view of another exemplary carrier of the invention, showing the upward flexing of the finger loops as it is lifted by a hand.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0012] Referring to the drawings, wherein like numerals generally refer to the same elements, there is shown in FIGS. 1-3 an integral carrier 10 for carrying multiple containers. Carrier 10 has a web 12 that is substantially planar. Web 12 has a pair of centrally located annular support openings 14 . Each support opening 14 is surrounded by a support rib 16 and has a finger loop 18 situated therein. Surfaces 18 a and 18 b of finger loops 18 are preferably radiused to provide comfortable gripping surfaces for carrying the carrier. Each finger loop 18 flattens at its points of attachment to the support rib 16 to increase upward flexibility upon lifting. The points of attachment of finger loops 18 to the support rib 16 are tangent to the outermost neck-engaging structures 20 .
[0013] A plurality of identical annular neck-engaging structures 20 are integral with the web 12 and are arranged around the periphery of the support openings 14 . Each neck-engaging structure 20 has a respective circumferential rib 22 . Each circumferential rib 22 has a radiused upper and lower surface 22 a and 22 b , respectively. Each neck-engaging structure 20 further has a plurality of flanges 24 projecting inwardly from circumferential rib 22 for releasably engaging the necks 26 of the containers 28 . The flanges 24 are oriented upwardly and comprise sections of a truncated cone. The inner edges 25 of flanges 24 form a circle and engage the necks 26 of the containers 28 , allowing carrier 10 to secure and support the containers.
[0014] Interconnecting each of the neck-engaging structures 20 are external ribs 30 . External ribs 30 , like support ribs 16 and circumferential ribs 22 , have radiused upper and lower surfaces. These interconnecting ribs add dimensional support to the carrier, much like I beams in a framed structure.
[0015] In a preferred embodiment, the thickness of flanges 24 is 20-25 mils, the thickness of ribs 16 , 22 and 30 and web 12 is 60 mils each, and the height of ribs 16 , 22 and 30 is 180 mils. Support ribs 16 surrounding the support openings 14 and external ribs 30 interconnecting the neck engaging structures 20 preferably have the same radius.
[0016] In a second embodiment, there is shown in FIG. 4 an integrally molded carrier 11 , also designed for carrying multiple containers. Carrier 11 comprises a plurality of neck-engaging structures 20 with smaller gaps 13 between them that are bridged by bridging tabs 15 and a pair of radial ribs 17 , tabs 15 and ribs 17 securing the neck-engaging structures 20 to one another. Neck-engaging structures 20 are substantially the same design as shown in FIGS. 1-2 . Larger gaps 19 are created by omitting radial ribs 17 on either side of tab 15 ′, thereby allowing sufficient room to accommodate a pair of opposing finger loops 18 . Finger loops 18 preferably also have radiused upper and lower surfaces 18 a and 18 b and are flat at the points of attachment to the outer neck-engaging structures 20 .
[0017] The carrier is manufactured using high pressure injection molding of heated and liquified polymer into a three-dimensional cavity, and is preferably made of a flexible material such as a polyolefin. In a most preferred embodiment, the polyolefin is high density polyethylene (HDPE) that has a tensile strength from about 4000 to about 5000 psi, and a brittleness temperature of less than −30° C. This material is readily recyclable, in contrast to the material used to make conventional die-cut thermo-formed carriers.
[0018] The carrier of the present invention concentrates structure into three-dimensional ribs, thereby reducing the surface area required to support containers. At the same time, this minimal surface area provides for a quality appearance while utilizing less material. The carrier is essentially planar and so does not obscure the container or product therein or labels, but instead provides high product and label visibility.
[0019] In addition, the thick ribs and radiused edges of the ribs and pair of opposing finger loops provide outboard points of attachment for superior comfort for lifting and carrying the carrier, and superior balance for carrying and handling containers. The carrier also provides superior release of the containers. The circumferential ribs around the angled, thin conical flanges provide support for the containers. The thin flanges easily flex to allow the containers to be removed by either lifting the carrier relative to the container or pulling the container down and away from the carrier.
EXAMPLES
[0020] Carriers of substantially the same designs shown in FIGS. 1-2 and 4 were fabricated by injection molding from HDPE having a specific gravity of 0.962, with a tensile strength of about 4800 psi (33 mPa), a flexural strength of about 7000 psi (48 mPa) and a brittleness temperature of approximately −30° C.
[0021] The so-fabricated carriers were easily and quickly secured over the annular flanges of six 12-ounce bottles ( FIG. 1 embodiment) and over six 12-ounce aluminum cans ( FIG. 4 embodiment) by placing the neck-engaging structures 20 over the bottle necks/can tops and pushing them down until the flanges 24 of the neck-engaging structures engaged the annular flanges 26 on the necks of containers 28 as illustrated in FIG. 3 . The carrier secured and supported the containers, yet readily disengaged by simply pulling the containers downward and away from the carrier.
[0022] The same basic neck-engaging structures with opposing finger loops may be incorporated into other multiple container carriers, such as carriers for fewer or more than six containers.
[0023] The terms and expressions which have been employed in the foregoing specification are used therein as terms of description and not of limitation, and there is no intention, in the use of such terms and expressions, of excluding equivalents of the features shown and described or portions thereof, it being recognized that the scope of the invention is defined and limited only by the claims which follow. | An integral carrier for carrying multiple containers by their necks is disclosed that has a plurality of annular neck-engaging structures and a pair of centrally located opposing finger loops that promote a balanced distribution of weight for ease in carrying and handling. | 1 |
CROSS-REFERENCES TO RELATED APPLICATIONS
The present application claims the benefit of U.S. Provisional Application No. 61/604,143, filed on Feb. 28, 2012, the full disclosure of which is incorporated herein by reference.
BACKGROUND
Hotels are establishments that provide lodging, meals, entertainment, and various personal services for the public. Many modern hotels include full service restaurants, swimming pools, fitness centers, business centers, childcare, conference facilities, and social function services. Most modern hotels include a fitness center. An issue with the fitness center is safety, or at least perceived safety or privacy for patrons, particularly in off-peak hours. Often, a hotel guest may feel uncomfortable working out in a fitness room with only one other person. In the later hours of the day or the earlier hours of the morning, when the fitness center may have little traffic, a hotel guest may find himself or herself working out with only one other person. This sharing of a fitness center without supervision or the comfort of others may be uncomfortable for some guests.
Although security measures can be taken, such as having a camera in a workout area, the camera may not provide the same comfort as having fitness personnel or other individuals present. However, due to the light traffic during these times and the need to limit hotel costs, it is not practical to place hotel staff in the fitness center.
BRIEF SUMMARY
The following presents a simplified summary of some embodiments of the invention in order to provide a basic understanding of the invention. This summary is not an extensive overview of the invention. It is not intended to identify key/critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some embodiments of the invention in a simplified form as a prelude to the more detailed description that is presented later.
In accordance with embodiments, a hotel room is provided that includes both living spaces and workout spaces. Thus, in accordance with embodiments, a hotel guest may choose to workout in his or her room, utilizing the spaces and structures provided in the room. Some of the workout areas may be permanently structured for workout, may be configured for dual use for workout or living spaces, or may be rearranged for alternate use between a workout configuration and a living configuration.
In embodiments, a floor workout zone is provided in the room. This floor workout zone can be used for yoga, workout with dumbbells, or other floor exercises. A yoga mat, dumbbells, or other exercise equipment may be provided for use in this area. When the user is done with the workout, the yoga mat and dumbbells can be put away, allowing the space to be used for living space instead of workout space.
In accordance with additional embodiments, a bench is provided in the room that includes leg locks so that a user may work out on the bench, including locking the user's legs into the bench and doing sit ups. The bench includes a leather or synthetic leather covering so that it may be easily cleaned during or after workouts. The bench not only provides workout features, but also can be used during a conventional hotel guest's stay. For example, the bench may be used for a luggage stand or for sitting while the hotel guest is dressing, for example, while putting on shoes.
In accordance with additional embodiments, a dual purpose bar is provided in the hotel room. This dual purpose bar can be used for both the hanging of clothes and as a chin-up or pull-up bar for the hotel guest. The dual purpose bar includes sufficient structural support to support the hotel guest.
For a fuller understanding of the nature and advantages of the present invention, reference should be made to the ensuing detailed description and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an isometric view of a guest hotel room having workout features in accordance with embodiments.
DETAILED DESCRIPTION
In the following description, various embodiments of the present invention will be described. For purposes of explanation, specific configurations and details are set forth in order to provide a thorough understanding of the embodiments. However, it will also be apparent to one skilled in the art that the present invention may be practiced without the specific details. Furthermore, well-known features may be omitted or simplified in order not to obscure the embodiment being described.
In accordance with embodiments, a hotel room is provided having various workout functions provided in the room. Thus, the room is usable both for traditional hotel accommodations and as a workout space for the hotel guest.
In embodiments, the hotel room is divided into multiple zones, separating sleeping and living areas from workout zones, but also having zones that have a dual purpose for hotel room accommodations and workout.
The workout zones of the room are provided with materials and mats or other equipment that permit the areas to be easily cleaned. Moreover, the spaces are clearly removed from sleeping areas of the room. These features provide a guest comfort, while providing working out and living spaces within the same room.
Referring now to FIG. 1 , a hotel guest room 20 is shown having guest accommodations, amenities and workout features. The room 20 includes multiple zones, including a sleeping zone 22 , a floor workout zone 24 , a bench zone 26 , and a closet zone 28 .
The sleeping zone 22 includes a bed 30 and night stands, clocks, radios or other features that are commonly found in hotel guest accommodations. This sleeping zone 22 may include, for example, carpet flooring or other conventional flooring material.
The floor workout zone 24 is spaced from the sleeping zone 22 and will typically include a tiled or other easily cleanable floor. As an alternative to the tile shown in the floor workout zone 24 , sports flooring, such as NEOFLEX #817 sports flooring, can be provided in the floor workout zone 24 . Other synthetic or natural sports flooring could be used in the floor workout zone 24 . The different floor covering in the floor workout zone 24 relative to the other spaces in the room provides not only a feel of a workout area, but also delineates the workout area from the sleeping zone 22 of the room 20 . In embodiments, the floor workout zone 24 includes a yoga mat 36 that can be stored in a convenient location, such as at the end of the floor workout zone 24 . Dumbbell weights 38 or other exercise equipment may be provided in the floor workout zone. The dumbbell weights 38 and the yoga mat 36 may be put away, and the floor workout zone 24 is then available for typical hotel guest amenities, such as use of a desk 70 and office area.
The bench zone 26 includes a dual purpose bench 50 . The dual purpose bench 50 includes a flat workout surface 52 with leg locks 54 at one end. The bench 50 is with a material that is easily cleaned and that is associated with working out, such as leather or a synthetic leather material. The bench 50 may be used by a hotel guest for exercises, for example with the dumbbell weights 38 , or for doing sit-ups or other calisthenics. For sit-ups, the user may lock his or her legs into the leg locks 54 in a manner known in the exercise bench art, and may perform sit-ups on the bench.
The dual purpose bench 50 also serves functions for typical hotel room accommodations. For example, the bench surface 52 may be used as a luggage stand. A hotel guest may also sit on the surface 52 while getting dressed or when talking on the phone, as examples.
The closet zone 28 includes a dual purpose bar 60 . In the embodiment shown in the drawings, the dual purpose bar is an inverted U-shape, attached to the floor at its distal, lower ends. The dual purpose bar 60 includes structural supports 62 extending rearwardly to a wall. The supports 62 prevent the dual purpose bar from moving, and provide hanging space for clothes or other items. The structural supports 62 suspend the bar 60 into the room a sufficient amount so that a hotel guest may use the dual purpose bar 60 as a chin-up or pull-up bar. In addition to the structural supports 62 , the dual purpose bar 60 may be used for hanging of clothes or other items.
Other variations are within the spirit of the present invention. Thus, while the invention is susceptible to various modifications and alternative constructions, certain illustrated embodiments thereof are shown in the drawings and have been described above in detail. It should be understood, however, that there is no intention to limit the invention to the specific form or forms disclosed, but on the contrary, the intention is to cover all modifications, alternative constructions, and equivalents falling within the spirit and scope of the invention, as defined in the appended claims.
The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. The term “connected” is to be construed as partly or wholly contained within, attached to, or joined together, even if there is something intervening. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate embodiments of the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.
Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.
All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein. | A hotel room that serves as guest accommodations and provides a fitness area for a guest. The hotel room includes different zones, at least one of which is a sleeping zone, and at least the other of which can serve a fitness function. The fitness zone may be convertible between living spaces and fitness, or may serve only a fitness function. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
Not Applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable.
REFERENCE TO A MICROFICHE APPENDIX
Not Applicable.
BACKGROUND OF THE INVENTION
1. Technical Field
This invention relates to elevator systems and, more particularly, to a control system for equalizing and directing elevator car usage assignments.
2. Prior Art
Virtually all “Elevator Group Systems” (conventional two button or destination type) of recent invention have been based on “Cost of Service” algorithms (e.g.: Shortest waiting times) using as few elevators in the group as possible, with no regard for equalization of service characteristics or equipment use. The results are lower average service characteristics, (waiting times, trip times, car loading, etc.) but a wide range of individual characteristics. (Some passengers have short waits and trip times while others have long waits and trip times.)
The net result of these designs is also that individual car utilization is disparate. (Elevator Cars often become under-utilized while others are overused.)
In virtually all present systems the passenger destination times, (the sum of waiting+loading+travel times) is the target and is paramount. No effort is made to equalize service to all passengers, equalize use of equipment, minimize total system stops or minimize trip and round-trip times.
Zone/demand assignments, under the SEEDS system, shall be related to the individual car and shall be totally fluid rather than fixed and related to landings.
Accordingly, a need remains for an elevator car usage assignment system to overcome the above-noted shortcomings. The present invention satisfies such a need by providing a destination based elevator group supervisory system designed to equalize service and equipment use. Such a system will minimize the range of system service characteristics to the greatest degree possible and results in shorter average waits, transfer times, trip times, round trip times, and equipment use. As a result, the system will provide greater elevator car availability and optimum demand response.
BRIEF SUMMARY OF THE INVENTION
In view of the foregoing background, it is therefore an object of the present invention to provide a system for equalizing elevator car usage. These and other objects, features, and advantages of the invention are provided by a computer program product for enabling a computer to equalize service characteristics and equipment usage in an elevator group supervisory system.
This destination based elevator group supervisory system is designed to equalize service and equipment use. The equalization of service and the equalization of equipment use, as this system's primary target, will minimize the range of system service characteristics to the greatest degree possible. The results (rather than the target of the system) will be shorter average waits, transfer times, trip times, round trip times and equipment use. The result; fewer total system stops and shorter trip and round trips times, will provide greater elevator car availability and optimum demand response.
It is noted the purpose of the foregoing abstract is to enable the U.S. Patent and Trademark Office and the public generally, especially the scientists, engineers and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of the technical disclosure of the application. The abstract is neither intended to define the invention of the application, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
The novel features believed to be characteristic of this invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organization and method of operation, together with further objects and advantages thereof, may best be understood by reference to the following description taken in connection with the accompanying drawings in which:
FIG. 1 is a schematic block diagram showing the computer software program product and associated steps, in accordance with the present invention;
FIG. 2 is a schematic block diagram of the software instructions for the computer system;
FIG. 3 is a schematic block diagram of step (f) of the computer program product;
FIG. 4 is a schematic diagram of step (h) of the computer program product;
FIG. 5 is a schematic block diagram showing the computer system and associated steps;
FIG. 6 is a schematic diagram showing the creation of car response zones (CRZ's); and
FIG. 7 is a schematic diagram showing the equalization of cars on an assigned basis.
DETAILED DESCRIPTION OF THE INVENTION
The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which a preferred embodiment of the invention is shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiment set forth herein. Rather, this embodiment is provided so that this application will be thorough and complete, and will fully convey the true scope of the invention to those skilled in the art. Like numbers refer to like elements throughout the figures.
The apparatus of this invention is referred to generally in FIGS. 1-5 by the reference numeral 10 and is intended to provide a service/equipment destination equalization system for elevators. It should be understood that the system 10 may be used to equalize the assignments of various elevator systems and should not be limited to use only with destination type elevator systems.
The elevators shall be arranged for group operation as defined by the ANSI/ASME A17.1 Code and CABO/A1117.1 1997 for elevators controlled by a group supervisory system.
Referring to FIGS. 1 and 5 , all elevators shall be arranged for automatic operation without attendant. The control of the elevator shall be completely automatic through data input terminals (DIT's) and a central group processor or ring of car processors as well as peripheral input devices (ADA, Security, Communication, etc.).
DIT's shall consist of a means of registering a passenger's desired destination or special function requirement and a visual and audible device to indicate the assigned elevator, its location or other relevant information.
The DIT's shall automatically insert a demand into the dispatching system and an elevator shall be assigned to that demand. The demand shall be defined by ORIGIN (location of DIT or peripheral device) and by desired DESTINATION.
The starting of a car shall be contingent upon the establishing of the door interlock circuit. The cars shall automatically slow down and stop level at the floors in response to DIT assignments. Stops shall generally, but not necessarily, be made in sequence, irrespective of the order in which the DIT assignments are made. Provisions shall prevent more than one car from responding to the same call.
The demand shall be assigned to a car in the most equitable means, considering the equalization of all system service characteristics and the equalization of equipment utilization.
Passengers shall be directed to board specific cars, thereby assuring that system management criteria is not diminished by passenger misdirection. Elevator boarding patterns will be organized in that passengers will queue in front of their assigned elevators rather than in an arbitrary grouping throughout the elevator lobby.
CAR SELECTION CRITERIA
The Service/Equipment Equalization Destination System (SEEDS) shall be arranged to equalize service to all demand origins and destinations, so as to prevent extended waits and trip times. All cars shall be available for assignment to all demands at any time, except those cars on special operational assignments. Under all traffic conditions, the equalization of origin/destination, car assignments shall be paramount.
The DIT's are the primary passenger devices required to input passenger movement demands. The SEEDS system shall receive complete data on passenger origin, destination and volume, shall analyze the data and instantly assign cars in order to best serve the total system demand.
Referring to FIG. 7 , SEEDS shall minimize and equalize by car, the number of system stops and round trip times required to handle a given volume of traffic, thus reducing overall passenger/elevator system interface times and the range of those times.
The SEEDS system shall consider the number of calls versus the number of cars in service and shall, based on the system algorithm, make immediate assignments, equalizing to the greatest degree possible, the number of assignments made to each car. This process will eliminate limitation of the number of destinations assigned to an individual car and the subsequent inability of the system to respond to demands. Only when the number of system calls is less than the number of available cars, shall the shortest passenger destination times, (the sum of waiting+loading+travel times) be paramount.
Referring to FIGS. 2-3 , assignment of ORIGIN/DESTINATION demands shall be made based on the following criteria:
System calls shall be assigned to cars in such a way that all cars receive the same number of assignments. (e.g.: eight different ORIGIN or DESTINATION demands entered into a four car system shall result in a two call per car assignment.)
Referring to FIGS. 6 and 7 , the system will assign coincidental destinations and origins to the same car, to the highest degree practical.
The system will assign origins and destinations to contiguous or near contiguous floors, based on looking ahead at two directional changes.
The system shall form temporary “Car Response Zones” (CRZ's) based on the call assignments on a particular car. Temporary CRZ's shall be created consisting of the first remaining assigned car call floor and the floors beyond the last assigned car call, ending at the next cars CRZ. This process will eliminate disparate assignments and reduce the round trip of each car.
The number of floors in a temporary zone shall be, not less than the number of floors served divided by the number of cars in service. Temporary CRZ's may overlap. Temporary CRZ's shall be re-established when the number of assigned car calls becomes less than the average number of car calls assigned to all cars.
When a car has no call assignments, its temporary CRZ shall remain until call assignments resume.
When a heavy specific ORIGIN to DESTINATION demand occurs, based on the number of DIT registrations, additional elevators shall be assigned to service that demand. Cars determined to be fully loaded will not be eligible for intermediate assignments beyond those previously assigned. ORIGINS and DESTINATIONS coincidental to those already assigned for that trip may be accepted. This heavy demand response shall be done in such a way as to equalize service to all demands.
An allocation that would cause a car to arrive in advance of the passenger arrival, shall be provided with limited extra “door hold open” time so that the elevator doors would not close before the intending passenger could enter the elevator. The extra time may be reduced to a minimum when the entering passenger breaks the door protection beam and the beam is reestablished.
In making this determination, the momentary location of the traveling passenger shall be considered by virtue of floor location and the walking distance to the cars from individual DIT's.
The SEEDS supervisory control shall be based on an “equalization-of-service and equipment use” algorithm. Its primary objective is to equalize service characteristics and equipment use. The equalization of service and the equalization of equipment use, as this system's primary target, will optimize the range of system service characteristics (total passenger destination times, total system stops, round trip times, handling capacity, etc.). The least total number of system stops and shortest round trip times shall be a direct result rather than a target of the SEEDS algorithm.
In this fashion the total call registration to destination time for all passengers in the system shall be kept to a minimum, as will the range of these characteristics.
Now referring to FIG. 4 , the ORIGIN/DESTINATION assignment process “System Response Cost” (SRC) of a new demand is comprised of 4 primary components:
The number of DIT demands shall be divided equally among the total number of cars in service and assigned based upon the location of the “Car Response Zones” (CRZ's) of each car.
System calls shall be assigned to cars in such a way that all cars receive the same number of assignments. (e.g.: eight different ORIGIN or DESTINATION demands entered into a four car system shall result in a two call per car assignment.)
The system will assign coincidental destinations and origins to the same car in the following order:
a) Cars with the same origin and destination.
b) Cars with the same origins, and destinations within the same CRZ.
c) Cars with the same destinations, and origins within the same CRZ.
d) Cars with the same origins or destinations.
The system will assign origins and destinations to contiguous or near contiguous floors, based on looking ahead at two directional changes. No car shall be assigned calls within a greater range than the number of floors served by the group divided by one less than the number of cars in the group.
The system shall form temporary “Car Response Zones” (CRZ's) based on the call assignments on a particular car. Temporary CRZ's shall be created consisting of the first remaining assigned car call floor and the floors beyond the last assigned car call, ending at the next cars CRZ. This process will eliminate disparate assignments and reduce the round trip of each car.
The number of floors in a temporary zone shall be, not less than the number of floors served, divided by the number of cars in service. Temporary CRZ's may overlap. Temporary CRZ's shall be re-established when the number of assigned car calls becomes less than the average number of car calls assigned to all cars.
During heavy up-peak traffic originating at the main entry level, that level shall be included in each car's temporary CRZ but shall not be considered as the first or last assigned call. During heavy down-peak traffic when the main entry level is the primary destination, that level shall be included in each car's CRZ but shall not be considered as the first or last assigned call.
When a car has no call assignments, its temporary CRZ shall remain until call assignments resume. New calls shall be assigned based on the following order:
The system will assign coincidental destinations and origins to the same car in the following order:
a) Cars with the same origin and destination.
b) Cars with the same origins and destinations within the same CRZ.
c) Cars with the same destinations and origins within the same CRZ.
d) Cars with the same origins or destinations.
A call whose ORIGIN and DESTINATION are within a car's temporary CRZ on a car with no assignments.
A call whose ORIGIN is within a car's temporary CRZ on a car with no assignments.
A call whose ORIGIN and DESTINATION are outside a cars temporary CRZ on a car with no assignments.
A call whose ORIGIN and DESTINATION are within a car's temporary CRZ on a car with fewer than the mean call assignments.
A call whose ORIGIN is within a car's temporary CRZ on a car with fewer than the mean call assignments.
A call whose ORIGIN and DESTINATION are outside a cars temporary CRZ on a car with fewer than the mean call assignments.
New calls are accepted and can be assigned to cars with up to two directional changes ahead.
The SEEDS “equalization-of-service and equipment use” supervisory algorithm shall operate as the sole system in service to all traffic demands. SEEDS is a singular solution for Up-Peak, Down-Peak, Inter floor or Off-Peak traffic or any combination thereof.
Cars will park based on the following priorities:
1. During light through peak traffic demands, cars will park at the last landing served and shall be available for immediate assignment.
2. Cars will only be zoned to serve specific tenant needs.
3. If main lobby traffic is heavier than other traffic, more than one car may be sent to the lobby, subject to real time demand.
4. In the absence of demands for a period of not less than five minutes, the cars shall remain at their last assignment except in cases where specific zone assignments are required. Cars will park with doors closed until an assignment is made.
System parameters may be changed based on individual application requirements.
The following features shall be provided by the SEEDS as appropriate:
Interrupted-Service Alert—If a car with assigned boarding stops goes out of service or is fully loaded resulting in a bi-pass prior to reaching the boarding floors, the waiting passengers at these floors shall be informed and asked to reenter their destination. These voice announcements are to be made at the floor enunciators.
Nuisance Calls—If a car responds to a boarding call and no passenger transfer occurs, the corresponding destination calls from that floor will be canceled. Floors that continually log nuisance calls will cause an alert to be communicated to an appropriate location.
Approach Time, Passenger v. Car—Passenger approach times, DIT to car entrance are compared to car approach times. Approach times will be considered in the assignment process. Cars forecast as arriving prior to passengers will not be assigned unless arriving empty and without further bookings; in this case the door-hold-open time will be extended to accommodate the approaching passenger.
Assignment By-Rule—A car assigned to stop at a floor when traveling in one direction will not be assigned a boarding stop at this floor for the opposite direction of travel, except when the stop is at the floor of direction reversal. This eliminates the chance of passengers entering a car and traveling in the wrong direction and reaching their destination only after a detour and direction reversal.
Handicap Operation—In addition to the DIT's destination registration means each floor terminal is to be supplied with a button engraved with the International Handicap Access wheelchair symbol. This button is to be the initiating button for handicapped passenger procedures. When a “wheelchair” button is pressed, a special journey mode shall be initiated, as prescribed under the CABO/A117.1 proposal. The following operation shall be enabled:
The destination is registered in a conventional manner.
Car assignment is confirmed both visually and by a tone that is repeated at the entrance identification lantern of the car assigned that call. The car identification lantern is illuminated and flashes to coincide with the audible signal at the DIT confirming to partially sighted and blind persons which car has been assigned.
The assignment is announced at the DIT (e.g. “take car A”) and car A announces its location.
The assigned car will be selected according to:
Space inside the car to permit a wheelchair user to board.
The ETA of the car must be later than the ETA of the passenger at the boarding entrance, assuming an extended 2-3 seconds per yard passenger approach time.
Preference for no exiting passenger for the boarding floor.
Upon arriving at the destination and opening the doors the elevator shall announce the open status of the doors and automatically extend the door “hold open time” to permit comfortable egress. The door operation shall be modified to initiate a slow closing of the doors. The car shall then return to normal service.
Other Features such as Independent Service, Firemen's Service, Code Blue, VIP etc., shall be provided through code entry or peripheral device and shall operate in traditional fashion. Hidden operating devices shall be exposed inside the car to accommodate these special operations.
The SEEDS will be arranged to provide restricted floor features as follows:
a) On a per floor basis for destinations only. This restriction shall be arranged to be over-ridden by a card key over-ride.
b) A signal in the DIT shall indicate registration of a restricted destination.
c) Control shall also be arranged to interface with a card key type Security System for all building floors.
For the purposes of the present specification, the above-mentioned terms are defined in the following manner:
Waiting Time:—Time from the registration of a call to the arrival of the car and opening of its doors. Not including extended approach time.
Trip Time:—The time from boarding to arrival at destination, including initial door dwell and close and arrival door open times.
Destination Time:—The sum of “Waiting Time” and “Trip Time”
Round Trip Time:—Time from trip origin to the second directional change.
Origin:—The location of the DIT or peripheral means of demand input.
Destination:—The registered intended floor.
Car Response Zones:—The floors to or from which a car is eligible for ORIGIN or DESTINATION assignment.
While the invention has been described with respect to a certain specific embodiment, it will be appreciated that many modifications and changes may be made by those skilled in the art without departing from the spirit of the invention. It is intended, therefore, by the appended claims to cover all such modifications and changes as fall within the true spirit and scope of the invention.
In particular, with respect to the above description, it is to be realized that the optimum dimensional relationships for the parts of the present invention may include variations in size, materials, shape, form, function and manner of operation. The assembly and use of the present invention are deemed readily apparent and obvious to one skilled in the art. | An elevator car equalization computer program product includes software instructions for enabling a computer to perform predetermined operations, a computer readable medium bearing the software instructions, and a computer system including a processor and a memory. The predetermined operations include the steps of: (a) receiving at least one user input from at least one data input terminal; (b) determining a location of an originating demand unique to each of the user inputs; (c) determining a location of a destination demand unique to each of the user inputs; (d) calculating a total number of the user inputs received within a predetermined time interval; (e) determining whether the total number of user inputs is less than or more than a total number of available elevators; (f) assigning an elevator to each of the locations of the originating demand; and (g) forming temporary call response zones based upon the elevator assignments. The present system provides shorter average waits, transfer times, trip times, round trip times and equipment use. | 1 |
FIELD OF THE INVENTION.
This invention relates to prostaglandin analogs and their synthesis. More particularly, it relates to a novel, simplified synthesis of prostaglandin analogs, and novel chemical compounds useful as intermediates in such synthesis.
BACKGROUND OF THE INVENTION AND PRIOR ART.
Prostaglandins (PGs) are organic carboxylic acids, namely cyclopentanes carrying two side chain substituents, typically linear C6-C8 side chains, bonded to adjacent positions on the cyclopentane nucleus. One of the side chains, the a-side chain, carries a terminal carboxylic acid group. Many are natural products found in mammalian organs and tissues (primary PGs), and exhibit a variety of physiological activities. Primary PGs generally have a prostanoic acid skeleton, which forms the basis of the nomenclature:
A significant number of synthetic PG analogs have been made and found to have useful pharmacological properties. These may have modified skeletons, and substituted and unsaturated side chains. PGs are characterized by a hydroxyl (or ketone) substituent on the cyclopentane nucleus, position 9.
Prostaglandin analogs are difficult to synthesize. Complications arise because of the requirements of the end products to have several functional groups and two side chains of significant size and complexity. Stereospecificity is commonly required, for substituent groups and for bonds in the core. Since the products are intended for pharmaceutical use, the range of industrially acceptable reagents, solvents, catalysts, etc. which can be used in their synthesis is limited to those having pharmaceutical industry acceptability.
A common starting material for PG analog synthesis is the commercially available Corey alcohol benzoate, of formula:
To convert this to a synthetic PG analog, many protection, functionalization, de-protection, etc. steps are required to form the desired side chains. U.S. Pat. No. 5,252,605 Ueno, issued Oct. 12, 1993, reports several PG syntheses starting from Corey alcohol which involve approximately fifteen steps. Inevitably, such a multi-step process is time consuming and expensive to conduct, and results in relatively low overall yield of final product.
An example of a synthetic prostaglandin analog of specific interest is lubiprostone, of formula:
This compound is marketed as “Amitiza”, for use in treatment of chronic idiopathic constipation, irritable bowel syndrome and post-operative ileus. Its synthesis presents significant technical challenge because of the chemical complexity of the fluorine containing substituent chain at the 12-position. Known methods for its synthesis suffer from the aforementioned disadvantages, namely a multi-step (typically 15-step) synthesis from Corey alcohol with consequent low yields of final product and time consuming nature of the process.
It is an object of the present invention to provide a novel synthetic method for preparing PG analogs, in fewer steps and in improved overall yield.
It is a further object to provide novel chemical compounds useful in the synthesis of PG analogs.
It is a specific object of the present invention to provide a novel synthesis of lubiprostone, starting from commercially available Corey alcohol.
SUMMARY OF THE INVENTION
One significant aspect of the present invention is a small class of novel chemical compounds comprising a cyclopentane nucleus fused at its 4,5 position with a 4-substituted 3,5-dioxalane ring, and fused at its 3a,6a-position with a lactone ring. The compounds have the formula:
where R represents an aryl group, preferably a substituted phenyl group such as p-methoxyphenyl (PMP). Subsequent reaction of a compound of formula A with a lower alkyl-aluminum compound such as di-isobutyl aluminum hydride (DIBAL) under properly selected conditions causes ring opening of the dioxalane at a specific position, as well as reduction of the lactone to lactol without over-reducing the lactol ring structure to a diol. The product of the ring opening reaction has a hydroxymethyl group at position 1 on the, cyclopentane nucleus, ready for chemical expansion to provide the β-chain of the selected target PG analog, and a protected hydroxyl group at position 2. In subsequent steps, the lactol ring can be opened chemically, and expanded to form the β-chain of the target compound, with the residue of the lactol ring forming the basis for the eventual 9-hydroxy or 9-keto group of the target PG analog. The formation of this ring-opened product B may be represented as follows:
It is totally unexpected that this reaction should take place without over-reducing the lactone ring. One would have predicted formation of a complex mixture of different reduction products, with such a plurality of potentially reducible groups and sites being subject to such a powerful reducing agent as DIBAL. Instead, by selection of appropriate reaction conditions, a high degree of selectivity to from product B is achieved. These conditions include selection of a reaction solvent which is a good solvent for the cyclopentane compound, and which is a polar, non-co-ordinating solvent that permits, and does not interfere with, co-ordination of the aluminum complex with the available oxygen of the ring structure, to the substantial exclusion of co-ordination of the aluminum to the solvent itself, and temperatures appropriate to maintain the stability of the organo-aluminum compound. Suitable such solvents include methylene chloride, dichloroethane, chlorobenzene, chloroform, toluene and mixtures thereof, and similar polar hydrocarbons, with methylene chloride being most preferred. Preferably low temperatures, below 0° C. and most preferably in the −40-−50° C. range.
Thus according to a first aspect of the present invention, there is provided in one embodiment a fused cyclopentane—4-substituted 3,5-dioxalane lactone compound useful as an intermediate in the synthesis of prostaglandin analogs, the compound having the formula A:
wherein R represents a lower alkoxy substituted phenyl group.
According to a second aspect, there is provided a process of preparing a substituted cyclopentane lactone compound of formula B, which comprises subjecting a compound of formula A as defined above to selective ring opening reduction with a lower alkyl-aluminum reducing agent in solution in a polar, non-coordinating solvent at a temperature at which the reducing agent is stable.
BRIEF REFERENCE TO THE DRAWING
The single FIG. 1 of accompanying drawings illustrates the overall reaction scheme embodying the present invention, in the preparation of lubiprostone, a preferred embodiment thereof.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the accompanying drawing FIG. 1 , the preferred synthesis according to the invention starts with Corey alcohol benzoate 10, which is commercially available. Reaction of this with sodium methoxide in methanol (room temperature, 1.5 hours) produces Corey lactone diol 12 in high yield (e.g. 97%) ready for further reaction.
A cyclopentane-lactone-dioxalane fused tricyclic compound 16, member of the class of compounds A of the present invention, is prepared by reacting Corey lactone diol 12 with anisaldehyde dimethyl acetal, compound 14, in the presence of trace amounts of acid. This reaction suitably takes place under reflux, over a period of, for example 3 hours. A dioxalane ring substituted at ring position 2 with p-methoxyphenyl (PMP) forms in high (85-90%) yield. In the next step, according to this preferred embodiment of the process, compound 16 is reacted with DIBAL, in solution in methylene chloride and toluene, and at a low temperature (e.g. −45° C.) at which DIBAL is stable. Ring opening of the dioxalane at a specific position occurs, without over-reduction the lactone structure to diol, thereby producing compound 18, a representative of class B referred to above, in a yield in excess of 80%. Compound 18 has a hydroxymetiyl group at position 1 on the cyclopentane nucleus, ready for chemical expansion to provide the α-chain of the selected target PG analog, and a hydroxyl group protected with p-methoxy benzyl at position 2.
Side chain expansion and derivatization can now take place using compound 18, advantageously expanding one side chain to that required in the target prostaglandin analog first, and subsequently expanding the second one to the target. Thus in the preferred embodiment where lubiprostone is the target compound, the α-chain is formed first. This is a linear heptanoic acid chain, which after formation merely needs simple protection of its terminal carboxylic acid group to confer stability and prevent its interference with other reactions. The ω-chain of lubiprostone is more chemically complex, involving a hemi-acetal and a di-fluorinated side chain. Introducing this chain second reduces the chances of fluorinated side chain losses in subsequent reactions, as the number of such reactions is reduced, the α-chain being already formed.
The first step in the a-chain expansion is reaction of compound 18 with (4-carboxybutyl)triphenylphosphonium bromide and sodium hexamethyl disilazane to cause opening of the lactone ring and condensation thereof to form a compound 20. This reaction suitably takes place in toluene solvent and at a temperature of −20 to −30° C., over a period of 2-3 hours. A double bond forms at position 5,6 of the side chain. Stereospecificity of the original Corey alcohol is retained. This reaction is analogous to that conducted in known prostaglandin synthesis process, although according to the invention it is applied to novel reagents and produces novel intermediates. The next step is the protection of the terminal carboxylic acid group, and this is done in known manner, by reaction of compound 20 with benzyl bromide (BnBr) in the presence of potassium carbonate at room temperature in acetone solvent, in two steps, over 18 hours, producing protected acid compound 22. A 55-65% yield is typically obtained in this step.
Next, a double oxidation of hydroxyl groups to keto and aldehyde groups is conducted. Protected compound 22 is oxidized with pyridine-sulfur trioxide in the presence of diisopropylethylamine and DMSO and methylene chloride solvent. The result is oxidation of the primary alcohol side chain group to aldehyde, and oxidation of the secondary, nuclear alcohol group to a keto functionality, producing compound 24.
Now the fluorinated side chain required in lubiprostone can start to be introduced. Thus the next step in the process is the reaction of compound 24 with dimethyl-(2-oxo-3,3-difluoroheptyl)phosphonate (compound 26), in the presence of sodium hydride and dimethoxyethane (DME), for example at 50 to 70° over 18 hours. The result is compound 28, in 60-70% yield.
The final reactions in lubiprostone synthesis are the hydrogenation of the double bonds in compound 28, ((7)-benzyl 7-((1R,2R,3R)-2-((E)-4,4-difluoro-3-oxoooct-1-enyl)-3-(4-methoxybenzyloxy)-5-oxocyclopentyl)hept-5-enoate) which is itself a novel, inventive compound and a feature of the present invention, and the deprotection thereof to remove the carboxylic acid protectant from the a-chain terminus, and the removal of the p-methoxybenzyl (OPMB) protectant to form the desired hemi-acetal ring. This is done in a single step, by hydrogenation using hydrogen over palladium/carbon catalyst in isopropanol medium, at room temperature over, e.g., 2 hours. This process is another significant feature of the present invention. The product is lubiprostone, compound 30, in a 75-80% yield for this step.
The illustrated process is capable of producing lubiprostone from Corey alcohol in eight steps at an overall yield in excess of 15%, which is most acceptable in syntheses of this type and is significantly higher than that achieved with prior art processes. Most of the reagents used are relatively inexpensive, with the possible exception of dimethyl-(2-oxo-3,3-difluoroheptyl)phosphonate (compound 26). This is a known compound, preparable from ethyl 2-oxo-hexanoate by reaction with ethyl 2,2-difluorohexanoate he following reaction scheme:
The specific preferred embodiment of the present invention is further described, for illustrative purposes, in the following specific experimental examples.
Experimental Procedure
Corey Lactone Diol 12. To a suspension of 10 (15 g, 54 mmol, 1 equiv) in methanol (75 mL) was added sodium methoxide (25% wt in methanol, 1.2 mL, 5.4 mmol, 0.1 equiv). The mixture was stirred at room temperature for 1.5 h and then hydrochloric acid solution (4 M in dioxane, approximately 1 mL) was added until the pH was 3-4. The solution was stirred at room temperature for 10 min and then concentrated to dryness under vacuum on a rotary evaporator. The resulting white solid was suspended in methyl tert-butyl ether (150 mL) and stirred at room temperature for 1 h. The solid was filtered, washed with methyl tert-butyl ether, and dried under vacuum for 10 min to afford 9.1 g of 12 (97%) as a white solid.
Protected Diol 16. To a suspension of 12 (5.0 g, 29 mmol, 1 equiv) in toluene (100 mL) was added anisaldehyde dimethyl acetal (14) (7.4 mL, 44 mmol, 1.5 equiv) and p-methoxy benzoic acid (44 mg, 0.29 mmol, 0.01 equiv). A condenser and a Dean-Stark apparatus were attached and the mixture was heated at 120° C. for 3 h while removing methanol by the Dean-Stark apparatus (approximately 2 mL). The reaction mixture was removed from the oil bath and stirred at room temperature for 15 min. Methyl tert-butyl ether (100 mL) was added and the mixture was cooled in an ice bath for 45 min. The resulting suspension was filtered, washed with methyl tert-butyl ether, and dried under vacuum for 10 min to afford 7.3 g of 16 (87%) as a white solid.
Lactol 18. A solution of 16 (14 g, 50 mmol, 1 equiv) in dichloromethane (500 mL) in a round-bottom flask containing a dropping funnel was flushed with N 2 for 5 min. The solution was cooled to −45° C. and diisobutylaluminum hydride (1 M in toluene, 150 mL, 150 mmol, 3 equiv) was added dropwise. The mixture was stirred for 1 hour and 20 min at −45° C. Buffer solution pH 7 (21 mL) was added dropwise and the solution was warmed to room temperature over 2 h. The suspension was filtered and washed with dichloromethane. The filtrate was concentrated to dryness under vacuum on a rotary evaporator to afford 13 g of 18 as a yellow oil (88% yield) which was used directly in the next step.
Diol 520. To a suspension of (4-carboxybutyl)triphenylphosphonium bromide (33 g, 75 mmol, 2 equiv) in toluene (220 mL) was added sodium hexamethyl disilazane (1 M in tetrahydrofuran, 262 mL, 262 mmol, 7 equiv). The mixture was stirred at room temperature for 1 h and then cooled to −25° C. Compound 18 in tetrahydrofuran (60 mL) was added dropwise and then warmed to room temperature over 4 h. Water (200 mL) was added and the organic layer was separated and extracted with water (2×50 mL). The aqueous washings were combined and 20% aqueous citric acid solution (125 mL) was added. The suspension was extracted with dichloromethane (4×100 mL). The organics were combined, dried over sodium sulfate, filtered, and concentrated to dryness under vacuum on a rotary evaporator to afford a yellow oil containing 20. The oil was dissolved in acetone (433 mL) and potassium carbonate (11 g, 77 mmol, 2 equiv) and benzyl bromide (9.1 mL, 77 mmol, 2 equiv) were added. The mixture was stirred at room temperature for 18 h, filtered, and concentrated to dryness under vacuum on a rotary evaporator. The crude oil was purified by column chromatography using 50% ethyl acetate/hexanes as eluant to afford 11 g of 22 as a yellow oil (64%).
Aldehyde 24. A solution of 22 (3.5 g, 7.4 mmol, 1 equiv) and dimethyl sulfoxide (10.5 mL) in dichloromethane (70 mL) was cooled to −15° C. Diisopropyl ethylamine (4.3 mL, 45 mmol, 6 equiv) was added followed by the addition of a solution of sulfur trioxide pyridine complex (7.1 g, 45 mmol, 6 equiv) in dimethyl sulfoxide (21 mL). The mixture was stirred at −15° C. for 1 h and was then diluted with 20% aqueous citric acid solution (20 mL). The aqueous layer was extracted with dichloromethane (3×20 mL) and the organics were combined, dried over sodium sulfate, filtered, and concentrated to dryness under vacuum on a rotary evaporator. The crude oil was purified by column chromatography using 20-40% ethyl acetate/hexanes as a gradient eluant to afford 3.1 g of 24 as a yellow oil (90%).
Protected Unsaturated Lubiprostone 28. A suspension of sodium hydride (60% dispersion in oil, 2.1 g, 53 mmol, 2.5 equiv) in tetrahydrofuran (500 mL) was added dropwise a solution of 26 (14 g, 53 mmol, 2.5 equiv) in tetrahydrofuran (165 mL). The mixture was stirred for 1 h at room temperature. A solution of 24 (9.9 g, 21 mmol, 1 equiv) in tetrahydrofuran (165 mL) was added dropwise. The mixture was then heated with stirring at 58° C. for 2 days. The mixture was cooled to room temperature and saturated aqueous ammonium chloride (200 mL) was added followed by water (200 mL). The aqueous layer was separated and extracted with ethyl acetate (3×150 mL). The organics were combined, dried over sodium sulfate, filtered, and concentrated to dryness under vacuum on a rotary evaporator. The crude oil was purified by column chromatography using 10-25% ethyl acetate/hexanes as a gradient eluant followed by a second column chromatography using 20% ethyl acetate/hexanes as to afford 7.8 g of 28 as a yellow oil (61%).
Lubiprostone. A mixture of 28 (8.0 g, 13 mmol, 1 equiv) and 5% palladium on carbon (containing 54.02% water, 5.1 g, 1.3 mmol, 0.1 equiv) in isopropanol (300 mL) was stirred under an atmosphere of H 2 (g) in a Parr hydrogenator at 40 psi for 2 h. The solution was then filtered through Celite™ and washed with methyl tert-butyl ether. The filtrate was concentrated to dryness under vacuum on a rotary evaporator and the resulting yellow oil was purified by a silica plug by first eluting with dichloromethane to remove impurities and then with methyl tert-butyl ether to remove the product. The methyl tert-butyl ether filtrate was concentrated to dryness under vacuum on a rotary evaporator to afford a yellow oil that was dried under vacuum for 3 h. The resulting oil was dissolved in dichloromethane (5 mL) with heating and a 1:1 solution of hexanes:petroleum ether (50 mL) was added. The solution was placed in an ice bath and stirred vigorously. Methyl tert-butyl ether (1 mL) was added and the product began precipitating out of solution. The mixture was stirred for 2 h, filtered, and washed with a solution of 2% dichloromethane in 1:1 mixture hexanes:petroleum ether to afford 4.1 g of Lubiprostone (78%) as a white solid.
Ethyl 2,2-Difluorohexanoate. To a 0° C. solution of ethyl 2-oxohexanoate (6.3 g, 40 mmol, 1 equiv) in dichloromethane (125 mL) was added dropwise (diethylamino)sulfur trifluoride (6.3 mL, 48 mmol, 1.2 equiv). The solution was warmed to room temperature over 4 h. Saturated aqueous sodium bicarbonate (100 mL) was slowly added. The aqueous layer was separated and extracted with dichloromethane (3×50 mL). The organics were combined, dried over sodium sulfate, filtered, and concentrated to dryness under vacuum on a rotary evaporator to afford 6.5 g of ethyl 2,2-difluorohexanoate (91%) as a yellow oil.
Dimethyl-(2-oxo-3,3-difluoroheptyl)phosphonate 26. A solution of dimethyl methylphosphonoate (6.5 g, 80 mmol, 2.2 equiv) in tetrahydrofuran (100 mL) was cooled to −78° C. and n-butyllithium (2.5 M in hexanes, 14 mL, 36 mmol, 1 equiv) was added dropwise. The solution was stirred at −78° C. for 30 min and ethyl 2,2-difluorohexanoate (6.5 g, 36 mmol, 1 equiv) was added dropwise. The solution was stirred at −78° C. for 1 h and warmed to 0° C. over 1 h. Pentane (100 mL) was added followed by the dropwise addition of 2M H 2 SO 4 to pH=6. The aqueous layer was separated and extracted with pentane (3×15 mL). The organics were combined, dried over sodium sulfate, filtered, and concentrated to dryness under vacuum on a rotary evaporator. The crude oil was purified by column chromatography using methyl tert-butyl ether as eluant to afford 4.1 g of 26 as a yellow oil (44%). | Fused cyclopentane—4-substituted 3,5-dioxalane lactone compounds useful as an intermediate in the synthesis of prostaglandin analogs are provided. The compounds have the formula A:
wherein R represents an aryl group such as p-methoxyphenyl.
This compound can be reacted with a lower alkyl aluminum compound to open the dioxalane ring and reduce the lactone to lactol, without over-reducing to diol. The resulting compound can be functionalized to insert chemical side groups of target prostaglandins, adding the required α-side chain and then the required ω-side chain sequentially and independently of each other. The compounds and process are particularly suitable for preparing lubiprostone. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to an optical information recording medium of write once (through a heat mode) type such as DVD-R, which is capable of performing a recording or reading data by means of a laser beam of a shorter wavelength region.
With respect to the means for recording and reading data such as images of character and graphic, picture or voice, an optical disc having a recording layer containing a pentamethine-based cyanine dye is known as a CD-R which is capable of recording and reading with a laser beam of 770 to 830 nm in wavelength. Recently however, DVD-R (a digital video disc-recordable, or a digital versatile disc-recordable), which is capable of recording and reading in high density with a red laser beam of 620 to 690 nm in wavelength for instance, which is shorter than the laser beam employed in the aforementioned CD-R, is now propagated as new media of the next generation.
As shown in Japanese Patent Unexamined Application H10-181211, the present applicants have proposed an optical information recording medium having a recording layer containing a specific kind of trimethine-based cyanine dye as being useful for such a DVD-R.
However, a trimethine-based cyanine dye having a benzene ring or a naphthalene ring, both being bonded to indole ring as shown in the aforementioned Japanese Patent Application, is accompanied with problems that when a substituent group in the benzene ring or naphthalene ring is hydrogen atom, etc. other than nitro group, the absorption spectrum of the recording layer having a dye layer containing such a dye becomes as shown in FIG. 1 . Namely, the absorbance h 2 of a second peak “b” representing an absorption due to the interaction and association between the dye molecules becomes too large in relative to the absorbance hl of the main peak “a” representing an absorption by the dye molecule itself which is based on the band gap energy in the dye molecule. As a result, the peak consisting of the main peak “a” and the second peak “b” fails to become sharp, and a half value width “d” of the spectrum (the width of the spectrum consisting of the main peak “a” and the second peak “b” in relative to the absorbance of h 1 /2) which represents the degree of the sharpness of peak also fails to become sufficiently small.
If the spectrum fails to become sufficiently sharp as mentioned above, the recording sensitivity or the absorbance per unit film thickness of a recording layer at the occasion of forming pits by making use of the irradiation of laser beam onto a recording layer cannot be sufficiently increased. This invites not only the problems that the thickness of the dye layer is required to be increased, the recording power is required to be increased, or the recording speed is required to be decreased, but also the problems that a so-called heat interference (wherein the deformation of the configuration of the pits may be caused due to the accumulation of heat at the space between the pits) tends to be brought about at the occasion of recording, thus giving a bad influence to the characteristics of the recording layer such as modulation amplitude or jitter.
BRIEF SUMMARY OF THE INVENTION
Therefore a first object of this invention is to provide an optical information recording medium having a recording layer which is capable of improving the ratio between the absorbance peak of a dye molecule and the association peak due to an association of the molecules in relative to a laser beam of shorter wavelength for the recording of the DVD in particular.
A second object of this invention is to provide an optical information recording medium which makes it possible to realize a recording material which is thin in film thickness and high in recording sensitivity to a laser beam of shorter wavelength for the recording of the DVD in particular.
A third object of this invention is to provide an optical information recording medium which is excellent in characteristics in terms of modulation amplitude, jitter, etc. in relative to a laser beam of shorter wavelength for the recording of the DVD in particular.
A fourth object of this invention is to provide an optical information recording medium which makes it possible to perform a high-speed recording with a small power in relative to a laser beam of shorter wavelength for the recording of the DVD in particular.
The present inventors have made an intensive study to solve the aforementioned problems and have finally found that a recording layer having a dye layer containing a trimethine-based cyanine dye having nitro group attached to a benzene ring or to a naphthalene ring, both being bonded to indole ring, is capable of minimizing the second peak in relative to the main peak shown in FIG. 1, thus enabling the spectrum consisting of a main peak and a second peak to become sharp.
Namely, according to this invention, there is provided (1) an optical information recording medium comprising a substrate on which a recording layer including a dye layer is formed; which is characterized in that said dye layer contains a trimethine-based cyanine dye represented by the following general formula [1]; and that said recording layer enables a recording and reading to be effected with a laser beam having a wavelength falling within a range of 620 nm to 690 nm.
wherein “A” represents any one of the following general formulas [2], [3], [4] and [5];
“A′” represents any one of the following general formulas [6], [7], [8] and [9];
“A” and “A′” may be the same or different from each other (where m and n respectively represents an integer of 1 or more); R and R′ may be the same or different from each other and are individually substituted or unsubstituted alkyl, carboxyl, alkoxycarbonyl, alkylcarboxyl, alkoxyl, alkylhydroxyl, aralkyl, alkenyl, alkylamide, alkylamino, alkylsufonamide, alkylcarbamoyl, alkylsulfamoyl, hydroxyl, halogen atoms, alkylalkoxyl, alkyl halide, alkylsulfonyl, alkylcarboxyl or alkylsulfonyl which are bonded to a metallic ion or alkyl, phenyl, benzyl, alkylphenyl, or phenoxyalkyl group (the hydrogen atom in the benzene ring portion and/or alkyl group portion may be substituted by a substituent group other than a metallic ion, such as alkyl, carboxyl, hydroxyl and a halogen atom); and X- is an anion selected from the group consisting of halogen atoms, PF6-, SbF6-, H3PO4, perchloric acid, hydroborofluoric acid, benzenesulfonic acid, toluenesulfonic acid, alkylsulfonic acid, benzenecarboxylic acid, alkylcarboxylic acid, trifluoromethylcarboxylic acid, periodic acid, SCN-, tetraphenyl borate and tungstic acid.
This invention also provides (2) an optical information recording medium of the aforementioned (1) wherein said dye layer further comprises, in addition to the trimethine-based cyanine dye represented by the aforementioned general formula [1], other kinds of dye at a ratio where the trimethine-based cyanine dye represented by the aforementioned general formula [1] occupies at least 50% by weight based on the total quantity of dyes.
This invention also provides (3) an optical information recording medium of the aforementioned (1) or (2) wherein said recording layer further comprises a metal complex.
In this invention, the recording layer is formed so as to enable the recording and reading to be effected with a laser beam having a wavelength falling within a range of 620 nm to 690 nm. This, in turn, means that the recording layer is made available for use in DVD-R.
The expression of the “recording layer” means in this invention not only a recording layer comprising a single or plural dye layers enabling pits to be formed thereon with a laser beam, but also an enhancing layer made of a resin for instance for adjusting the refractive index or film thickness of the optical information recording medium with a view to adjust the optical property of the optical information recording medium, and also an intermediate layer to be interposed between a substrate and a dye layer or between a plurality of dye layers.
The aforementioned trimethine-based cyanine dye contained in the dye layer and represented by the aforementioned general formula [1] can be optionally selected from those wherein “A” is optionally selected from the general formulas [2], [3], [4] and [5], “A′” is optionally selected from the general formulas [6], [7], [8] and [9], and “A” and “A′” can be optionally combined. For example, the compounds of the general formulas [2] may be optionally combined with any one of the compounds of the general formulas [6], [7], [8] and [9]. Likewise, the compounds of the general formulas [3], [4] and [5] may be optionally combined with any one of the compounds of the general formulas [6], [7], [8] and [9]. The “m” and “n” in the substituent groups (NO 2 )m and (NO 2 )n in “A” and “A′” are individually an integer of 1 or more. These dyes may be employed singly or in combination of two or more kinds.
FIG. 1 illustrates the absorbance to the wavelength of a laser beam when a recording layer having a dye layer containing a trimethine-based cyanine dye having nitro group attached to a benzene ring or to a naphthalene ring, both being bonded to indole ring, is irradiated with the laser beam. Namely, the ratio in absorbance of the main peak “a” to the second peak “b” (h 2 /h 1 ) can be made into less than 0.8, and at the same time, the half value width “d” of the spectrum consisting of the main peak “a” and the second peak “b” can be made less than 100 nm.
By contrast, when other kinds of substituent group (for example, hydrogen atom) are employed in place of nitro group constituting a substituent group of A and A′ in the aforementioned general formula [1], the absorbance ratio (h 2 /h 1 ) cannot be made into less than 0.8, i.e. it would become 0.8 or more, and also, the half value width “d” of the spectrum cannot be made less than 100 nm, i.e. it would become 100 nm or more.
It become possible, when nitro group is introduced into the benzene ring or naphthalene ring which are bonded to the indole ring of trimethine-based cyanine dye as mentioned above, to minimize the second peak and to enable the spectrum consisting of the main peak and the second peak to become sharp. As a result, the absorbance per unit film thickness of the recording layer can be increased and hence, the recording efficiency can be enhanced, i.e. so-called recording sensitivity can be improved. When the recording sensitivity can be improved in this manner, the film thickness of the recording layer can be made thinner as compared with the conventional recording layer, or not more than 70 nm, and even if the film thickness of the recording layer is not more than 70 nm, it is possible to enable the modulation amplitude to meet the present standards. Further, since the film thickness is made relatively thin, the accumulation of heat between pits at the moment of recording can be suppressed, thereby making it possible to inhibit the deformation of configuration of the pits due to the accumulation of heat (or so-called heat interference phenomenon) and to improve the jitter characteristics.
If the recording sensitivity can be improved and at the same time, the characteristics regarding the modulation amplitude, jitter, etc. can be improved in this manner, it becomes possible to reduce the power for recording and enhance the recording speed.
The recording layer according to this invention may include one or more kinds of additional dye other than the trimethine-based cyanine dye represented by the aforementioned general formula [1], this additional dye being included in the same dye layer as that of the trimethine-based cyanine dye or in a separate dye layer. In this case, when the trimethine-based cyanine dye represented by the aforementioned general formula [1] is included at ratio of not less than 50% by weight based on the total quantity of the dyes, it is still possible to enable the recording layer to meet the present standards though the characteristics such as the modulation amplitude and jitter may be somewhat deteriorated as compared with the recording layer where the aforementioned additional dye is not included at all.
As for the aforementioned additional dye, trimethine-based cyanine dyes represented by the following general formula [10] can be employed.
wherein “B” represents any one of the following general formulas [11], [12], [13] and [14];
“B′” represents any one of the following general formulas [15], [16], [17] and [18];
“B” and “B′” may be the same or different from each other (where D 1 and D 2 may be the same or different from each other and are individually hydrogen atom, alkyl, alkoxyl, hydroxyl, halogen atoms, carboxyl, alkoxycarbonyl, alkylcarboxyl, alkylhydroxyl, aralkyl, alkenyl, alkylamide, alkylamino, alkylsufonamide, alkylcarbamoyl, alkylsulfamoyl, alkylsulfonyl, phenyl, cyano, ester, nitro, acyl, allyl, aryl, aryloxy, alkylthio, arylthio, phenylazo, pyridinoazo, alkylcarbonylamino, sulfonamide, amino, alkylsulfone, thiocyano, mercapt, chlorosulfone, alkylazomethine, alkylaminosulfone, vinyl or sulfone group; p and q respectively represents the number of substituent groups, which is an integer of 1 or more; (however, the case where D 1 and D 2 are simultaneously nitro group is excluded); and “R” and “R′” are the same as those of the aforementioned general formula [1]).
In the aforementioned general formula [10], “B” can be optionally selected from the aforementioned general formulas [11], [12], [13] and [14], “B′” can be optionally selected from the general formulas [15], [16], [17] and [18], and “B” and “B′” can be optionally combined. For example, the compounds of the general formulas [11] may be optionally combined with any one of the compounds of the general formulas [15], [16], [17] and [18]. Likewise, the compounds of the general formulas [12], [13] and [14] may be optionally combined with any one of the compounds of the general formulas [15], [16], [17] and [18]. The “p” and “q” in the substituent groups (D 1 )p and (D 2 )q in “B” and “B′” are individually an integer of 1 or more.
As for the method of synthesizing the dyes represented by the aforementioned general formulas [1] and [11], the method set forth in “The Chemistry of Synthetic Dyes, Vol. 14” may be employed.
The trimethine-based cyanine dye represented by the general formulas [1] and a combination of this trimethine-based cyanine dye and the aforementioned additional dye may be exclusively employed. Additionally, in view of improving the light resistance of the recording layer, a metal complex may be included as a light-stabilizing agent in the dye layer or in another layer.
As for such a metal complex, the following compounds represented by the following general formulas [19] may be employed.
wherein R 1 and R 2 are respectively SO 2 R 3 ( R 3 is represented by the general formula [20])
halogen atom, phenyl, alkyl, cyano, thioalkyl or alkylsulfonyl; r and s are respectively an integer of 1 to 4; R 4 is alkyl group; Y is N or P; and M is a metal such as Cu, Co and Ni.
Specific examples of compounds belonging to the aforementioned general formula [19] include, in addition to the those shown in the following Examples, the compounds represented by the following general formulas [21] and [22].
The manufacture of the optical information recording medium according to this invention can be performed as follows.
First of all, a solution containing a cyanine dye represented by the aforementioned general formula [1], a solution containing this cyanine dye and a different kind of cyanine dye represented by the aforementioned general formula [10] or the aforementioned additional dye (the cyanine dye represented by the aforementioned general formula [1] should preferably be included at ratio of 50% by weight or more), or a solution which further contains, in addition to the aforementioned dyes, a metal complex represented by the aforementioned general formula [19] is dissolved in a solvent to obtain a dye solution, which is then coated on a transparent substrate. The solvent to be employed in the preparation of this dye solution may be selected from chloroform, dichloroethane, a fluorine-based solvent such as fluorinated alcohol, methylethyl ketone, dimethylformamide, methanol, toluene, cyclohexanone, acetylacetone, diacetone alcohol, cellosolves such as methyl cellosolve, and dioxane. The mixing ratio of the cyanine dye in this case should preferably be 1 to 10% by weight.
As for the material for the substrate to be employed in this invention, glass, or plastics such as epoxy resin, methacryl resin, polycarbonate resin, polyester resin, polyvinyl chloride resin and polyolefin resin may be employed. The substrate may be provided in advance with tracking grooves or pits, which may be provided with a signal required for an address signal.
The coating of the aforementioned cyanine dye on a substrate should preferably be performed by means of a spin-coating method. The film thickness after being dried of the dye layer may be the same as that adopted for DVD-R.
The recording layer according to this invention may contain a singlet oxygen quencher excluding the aforementioned metal complex, a light absorbent, a radical scavenger, etc.
The optical information recording medium according to this invention may include a reflection layer in addition to the recording layer. This reflection layer may be provided on its surface with a protective layer. This protective layer may also be deposited on the exposed surface (the surface from which a laser beam is irradiated) of the substrate.
As for the reflection layer, a film of high reflectivity, such as a metallic film may be employed. This metallic film can be formed by the vapor-deposition or sputtering of a metal such as Au, Al, Ag, Cu, Pt, an alloy comprising any of these metals or other kinds of metal, or an alloy containing other trace component. The protective layer is formed for the purpose of protecting or improving the optical information recording medium, and can be formed by coating a solution of a radiation cure type resin (such as an ultraviolet cure type resin) on a given surface by means of spin coating for instance and then radiation-curing the coated layer.
As a result, an optical disc comprising a substrate provided on its surface with a recording layer, an reflection layer and additionally a protective layer, etc. can be obtained. The optical disc comprising at least a recording layer as an essential layer and any other optional layer(s) may be superimposed on another optical disc comprising at least a recording layer as an essential layer and any other optional layer(s), or one substrate may be laminated on another substrate of an optical information recording medium.
The adhesives and methods for forming this laminated structure may be suitably selected by making use of an ultraviolet-curing resin, a cationic-curing resin, a pressure sensitive adhesive double coated tape, a hot-melt method, a spin-coating method, a dispense method (extrusion method), a screen printing method, a roll coating method, etc.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
FIG. 1 is a graph showing an absorption spectrum of a recording layer comprising a dye layer containing a trimethine-based dye (a dye belonging to the aforementioned general formula [10]) which does not belong to the aforementioned general formula [1] of this invention;
FIG. 2 is a graph showing an absorption spectrum of a recording layer comprising a dye layer containing a dye representing one example of the dyes belong to the aforementioned general formula [1] of this invention;
FIG. 3 is a graph showing an absorption spectrum of a recording layer comprising a dye layer containing a dye representing another example of the dyes belong to the aforementioned general formula [1] of this invention;
FIG. 4 is a graph showing an absorption spectrum of a recording layer comprising a dye layer containing a dye representing another example of the dyes belong to the aforementioned general formula [1] of this invention (the same kind of dye as employed in FIG. 3) and a dye belonging to the aforementioned general formula [10]; and
FIG. 5 is a graph showing an absorption spectrum of a recording layer comprising a dye layer containing an azo dye.
DETAILED DESCRIPTION OF THE INVENTION
This invention will be further explained in detail with reference to the following preferred embodiments.
A polycarbonate substrate provided with a track pitch 0.74 μm in length (it may be 0.80 μm) and only wobble signal (pre-pit may also be included) was employed. Trimethine-based cyanine dyes for the dye layer of a recording layer were selected as follows. Namely, an indolenine-based trimethine cyanine dye represented by the aforementioned general formula [1] where (1) a dye formed of a combination of the general formulas [2] and [6]; (2) in particular, a dye wherein m and n are both 1; (3) R and R′ are the same kind of group selected from alkyl or phenylalkyl group (lower alkyl group) mainly having 8 carbon atoms and having no branch; (4) in particular, X − is an anion of perchloric acid was selected. Then, a solution of dye meeting the aforementioned conditions (1) to (4) was respectively prepared. Additionally, a solution containing a dye meeting the aforementioned conditions of (1) to (4) and a metal complex belonging to the aforementioned general formula [19] where R 3 is represented by the general formula [20] was prepared. Furthermore, a solution containing 60 to 70% by weight (based on the total quantity of dyes) of a dye meeting the aforementioned conditions (1) to (4), and another kind of indolenine-based trimethine cyanine dyes represented by the aforementioned general formula [10] where (5) a dye formed of a combination of the general formulas [11] and [16]; (6) in particular, a dye wherein D 1 and D 2 are both hydrogen atom, (7) R and R′ are different from each other and selected from a lower alkyl group having 3 or 4 carbon atoms; (8) in particular, X − is an anion of iodine was prepared. Then, each solution was spin-coated on the polycarbonate substrate to form a dye layer having a film thickness of 50 to 70 nm.
In this case, the absorption spectrum of each of the recording layers could be controlled to 0.8 or less, more preferably 0.6 to 0.75 in absorbance ratio of the absorption peaks (h 2 /h 1 shown in FIG. 1) and at the same time, the half value width “d” of the spectrum consisting of the main peak “a” and the second peak “b” could be controlled to 100 nm or less, more preferably 80 nm to 100 nm.
Thereafter, a reflection layer consisting of Au or Al was deposited on the dye layer by means of sputtering. A protective layer comprising an ultraviolet-curing resin was further spin-coated on the reflection layer. Then, a pair of the optical discs thus obtained were superimposed via an adhesive layer comprising an ultraviolet-curing resin which was spin-coated on the polycarbonate substrate, thereby obtaining a laminated-disc type optical disc.
Then, a laser beam of 620 nm to 690 nm was irradiated onto these optical discs thereby to perform a recording, finding that an improvement in characteristics such as modulation amplitude and jitter. As compared with the optical disc where only a dye meeting the aforementioned conditions (5) to (8) was employed, and a dye meeting the aforementioned conditions (1) to (5) and belonging to the aforementioned general formula [1] was not employed, these optical discs enabled to minimize the power for recording, and to increase the recording speed when the same power for recording as that of the conventional optical disc was employed.
This invention will be further explained in detail with reference to the following examples.
EXAMPLE 1
A transparent polycarbonate substrate having a thickness of 0.6 mm, an outer diameter of 120 mm and provided with a spiral groove 0.32 μm in width, 100 nm in depth and 0.74 μm in pitch was molded by means of an injection molding method.
Then, a trimethine-based cyanine dye represented by the following general formula [23] (Nippon Kankoh-Shikiso Kenkyusho Co., Ltd.) and a metal complex represented by the following general formula [24] as a light-stabilizing agent were mixed together at a weight ratio of 95:5 to obtain a mixture. Then, this mixture was dissolved in 2,2,3,3-tetrafluoro-1-propanol (Tokyo Kasei Kogyo Co., Ltd.; hereinafter referred to as TFP) to obtain a solution containing 3% by weight of the aforementioned mixture. This solution was then coated on the substrate by means of a spin-coating method to obtain a recording layer consisting of a photosensitive dye film having a film thickness of 60 nm.
When the absorption spectrum of the recording layer (the wavelength dependency of the absorbance (Abs) under a wavelength ranging from 400 to 800 nm) was measured by making use of a visible ultraviolet spectrometer (U-4000; Hitachi, Ltd.) to obtain the spectrum as shown in FIG. 2 . The absorbance ratio of the second peak to the main peak (corresponding to the absorbance ratio h 2 /h 1 in FIG. 1) was 0.74, and the half value width of the spectrum (corresponding to the width of the spectrum consisting of the main peak and the second peak at h 1 /2 in FIG. 1) was 96 nm.
Next, a reflection layer consisting of an Au film having a film thickness of 80 nm was formed, by means of sputtering method, on the surface of a portion (a region 44 mm to 117 mm in diameter) of the recording layer deposited on the substrate.
Furthermore, an ultraviolet-curing resin (SD-211; Dainippon Ink & Chemicals Inc.) was spin-coated on the surface of the reflection layer, and then allowed to cure by irradiating ultraviolet rays to the coated layer to obtain a protective film having a film thickness of 5 μm.
Then, an ultraviolet-curing resin (SD-318; Dainippon Ink & Chemicals Inc.) was dripped on the protective film on the portion of the recording layer. Thereafter, another substrate which was molded in the same manner as mentioned above was placed on the surface of the substrate carrying thereon the aforementioned ultraviolet-curing resin. After the resin interposed between these substrates was allowed to disperse by means of a spin-coating method, ultraviolet rays was irradiated, via the substrate which was molded in the same manner, to the ultraviolet-curing resin to cure it, thereby forming an adhesive region 25 μm in thickness and 32 mm to 120 mm in diameter and obtaining a laminated-disc type optical disc.
Then, a recording was performed on this optical disc by making use of a recording machine (DDU-1000; numerical aperture=0.6, and laser wavelength=635 nm; Pulsetec Industries Co., Ltd.) under a linear velocity of 3.5 m/sec., and the jitter was measured by making use of a time interval analyzer (TA-320; Yokogawa Electric Co., Ltd.). According to the DVD Specification for Read-Only DISC, the Data to Clock Jitter (jitter) is a data which can be obtained by normalizing the deviation value σ of the binarize.data.edge signal by taking the channel bit rate=26.6 Mbps (38.23 nsec) as a standard clock. The evaluation of jitter is determined based on 8-16 signal modulation where the minimum pit length is set to 0.4 μm and the linear velocity is set to 3.5 m/sec. The value of jitter should be at most 9% or preferably 8.5% or less in view of preventing an accidental demodulation (decord) of the signal.
Furthermore, the modulated amplitude after recording (I 14 /I top ) was also measured by making use of a laser beam 650 nm in wavelength. In this case, the value of I top is a maximum reflection light quantity under HF (EFM) signal and almost identical with the value of a maximum reflection light quantity of I 14 . This I 14 is a signal of optical modulation component which can be derived from a difference in light quantity between the light quantity that is diffracted at the longest pit to be recorded in the groove to be recorded and then returned to the objective lens and the light quantity that is reflected at the non-pit portion and then returned to the objective lens.
Then, a light resistance test was performed on the above-obtained optical discs by way of W.O.M. (Weather-Ometer). The measurement was performed using Atras Weather-Ometer C135A (Toyo Seiki Seisakusho) under the conditions of 30° C. in temperature, 70 to 80% in relative humidity, 80 hours in irradiation of light of 6.5KW on the main surface of the disc using xenon light source, thereby to obtain the modulated amplitude (I 14 /I top ) after and before the recording. The results of the measurements are shown in Table 1. By the way, the standard values which are presently in force are also shown in Table 1.
TABLE 1
Absorption
Half value
ratio (h 2 /
width (nm)
Jitter
Modulation I 14 /I top (%)
h 1 in FIG. 1)
(“d” in FIG. 1)
(%)
Before test
After test
Standards
—
—
<9
>60
>60
Example 1
0.74
96
8.0
70
65
Example 2
0.77
98
8.0
72
68
Example 3
0.79
99
8.5
66
62
Example 4
0.77
98
8.0
74
20
Comp.
0.97
130
15.0
70
15
Ex. 1
This Example illustrates a case where a trimethine-based cyanine dye represented by the general formula [1] wherein A and A′ are both a benzene ring having one nitro group, and B and B′ are both the same kind of alkyl group having 8 carbon atoms. It will be seen that this optical disc is capable of recording by a laser beam of 635 nm in wavelength and of reading by a laser beam of 650 nm in wavelength, that the modulation amplitude is also high, and that the jitter is not so high. Furthermore, in view of the modulated amplitude obtained after and before the recording, the light resistance of the recording layer is good.
EXAMPLE 2
An optical disc was manufactured by forming a recording layer comprising a dye layer and processing the recording layer in the same manner as illustrated in Example 1 except that a trimethine-based cyanine dye represented by the following formula [25] belonging to the general formula [1] was substituted for the trimethine-based cyanine dye NK-2084. Then, the measurement was performed on this recording layer in the same manner as illustrated in Example 1, the results of measurements being shown in Table 1 and in FIG. 3 . The measurements on the optical disc were also performed in the same manner as described in Example 1, the results of measurement being shown in Table 1.
Although the dye employed for the optical disc of this example was altered from that employed in Example 1 in that R and R′ were formed of the same kind of phenylethyl group, it was possible to perform the recording with a laser beam of 635 nm in wavelength and to perform the reading with a laser beam of 650 nm in wavelength. Jitter was not so high, and the modulation amplitude was slightly better than that of Example 1.
EXAMPLE 3
An optical disc was manufactured by forming a recording layer comprising a dye layer and processing the recording layer in the same manner as illustrated in Example 1 except that the trimethine-based cyanine dye NK-2084, a trimethine-based cyanine dye (NK-4370; Nippon Kanko-Shikiso Kenkyusho Co., Ltd.) represented by the general formula [26], and a metal complex were employed at a weight ratio of 60:35:5, respectively. Then, the measurement was performed on this recording layer in the same manner as illustrated in Example 1, the results of measurements being shown in Table 1 and in FIG. 4 . The measurements on the optical disc were also performed in the same manner as described in Example 1, the results of measurement being shown in Table 1.
Although the optical disc of this example is featured in that a trimethine-based cyanine dye NK-2084 belonging to the general formula [1] was co-used with a trimethine-based cyanine dye NK-4370 belonging to the general formula [10] at a mixing ratio of 60:35 in weight ratio, it was possible to perform the recording with a laser beam of 635nm in wavelength and to perform the reading with a laser beam of 650 nm in wavelength. Jitter was higher than that of Examples 1 and 2, and the modulation amplitude was also slightly deteriorated from that of Examples 1 and 2. However, these values were found to meet the standards.
EXAMPLE 4
An optical disc was manufactured by forming a recording layer comprising a dye layer and processing the recording layer in the same manner as illustrated in Example 2 except that although the trimethine-based cyanine dye represented by the formula [25] was employed, the metal complex represented by the formula [24] was not employed. Then, the measurement was performed on this recording layer in the same manner as illustrated in Example 1, the results of measurements being shown in Table 1 (the absorption spectrum, the calculated value of h 2 /h 1 based on this absorption spectrum, and “d” are almost the same as those shown in FIG. 2 ). The measurements on the optical disc were also performed in the same manner as described in Example 1, the results of measurement being shown in Table 1.
Although a metal complex was not employed as a light stabilizer in the optical disc of this example, it was possible to perform the recording with a laser beam of 635 nm in wavelength and to perform the reading with a laser beam of 650 nm in wavelength. Jitter was not so high, and the modulation amplitude was slightly better than those of Examples 1 and 2. However, the light resistance test thereof indicated a poor result.
COMPARATIVE EXAMPLE 1
An optical disc was manufactured by forming a recording layer comprising a dye layer and processing the recording layer in the same manner as illustrated in Example 1 except that an azo dye (Product No. 36,482, Disperse Red 13, Aldrich Co., Ltd.) was substituted for the trimethine-based dye NK-2084, and the metal complex represented by the formula [24] was not employed. Then, the measurement was performed on this recording layer in the same manner as illustrated in Example 1, the results of measurements being shown in FIG. 5 and in Table 1. The measurements on the optical disc were also performed in the same manner as described in Example 1, the results of measurement being shown in Table 1.
In the optical disc of this comparative example, an azo dye which, of course, not only does not belong to the aforementioned general formula [1] but also does not belong to cyanine dye was employed and a metal complex was not employed as a light stabilizer. As a result, the absorbance ratio of the second peak/the main peak, as well as the half value width of the spectrum consisting of the main peak and the second peak were both larger than those of the above examples. Jitter was also out of the standards. The light resistance test thereof also indicated a poor result.
As explained above, there are clear differences between the products of this invention and the product of the comparative example with respect to the absorbance ratio of the second peak/the main peak, as well as to the half value width of the spectrum. Namely, the absorption peak of any the recording layer of the Examples was found more sharp as compared with that of Comparative Example. This fact is clearly reflected on the jitter characteristics. Further, when a metal complex was co-used as a light stabilizer, the light resistance of the recording layer was greatly improved.
According to this invention, the absorbance ratio between the second peak and the main peak with respect to a laser beam of short wavelength for the recording of DVD in particular can be greatly improved, and at the same time, the half value width of the spectrum consisting of these peaks can be minimized, thus making it possible to obtain an optical disc exhibiting a sharp peak of the spectrum. As a result, it is possible to provide a recording layer which is high in recording sensitivity and thin in film thickness, and at the same time, to provide an optical information recording medium which is excellent in characteristics in terms of modulation amplitude, jitter, etc., and makes it possible to perform a high-speed recording with a small power. | An optical information recording medium having a recording layer comprising a dye layer containing a trimethine-based cyanine dye having nitro group attached to a benzene ring or to a naphthalene ring, both being bonded to indole ring, is capable of minimizing the second peak in relative to the main peak shown in FIG. 1 , thus enabling the spectrum consisting of a main peak and a second peak to become sharp. The recording layer is capable of performing the recording and reading with a laser beam having a wavelength falling within a range of 620 nm to 690 nm. | 8 |
BACKGROUND OF THE INVENTlON
The invention relates to an apparatus for preheating granular ore or the like by means of hot gases, in particular flue gases obtained from a rotary tubular kiln. The apparatus has a shaft which is provided with vertical walls and through which hot gases flow from below in an upward direction, at least one inlet chute provided thereabove, a discharge collector provided underneath thereof and one or more passages which are provided between the shaft and the enlarged inlet cross section of the discharge collector and which serve as gas inlets.
Known apparatus for preheating the feed material such as granular ore or pellets (prior to its introduction into the tubular kiln) wherein the flue gases of the kiln are passed in cross flow through a mass of accumulated material by virtue of horizontal slots in the side walls of the shaft (so-called Venetian blind shaft preheaters), have the disadvantage that the feed material undergoes sintering along the surfaces facing the flow, whereby due to uneven flow through the material the heating is rendered inadequate and uneconomical.
A further known shaft preheater of the aforesaid type, in which gases pass through the shaft upwardly from below also fails to provide an adequate utilization of the heat of the flue gases of the kiln.
SUMMARY OF THE INVENTION
It is an object of the invention to provide an improved apparatus of the above-outlined type to ensure an amelioration of its heat output and to achieve a uniform heating of the ore or pellets to be treated.
This object and others to become apparent as the specification progresses, are accomplished by the invention, according to which, briefly stated, the discharge collector is provided with vertical side walls, a central, downwardly flaring insert and a discharge device at its lower end.
It is an advantage of the apparatus according to the invention that the gases flow substantially uniformly through the feed material and the mass flow of the granular ore or pellets over the entire cross section of the shaft as well as the discharge collector proceeds uniformly. On the outer surfaces of the material pile exposed to the gas, a continuous exchange of the material takes place so that a sintering of the ore due to the coal dust particles contained in the flue gas is avoided. Due to the thorough and uniform flow through the material, the output of the after-connected fan may be designed to be small.
The upper end of the downwardly flaring insert extends approximately to the level of the largest horizontal cross section of the conical material pile emerging from the shaft and the area of such cross section (determined by the vertical walls of the discharge collector) is 1.5 to 1.6 times greater than that of the cross-sectional area of the shaft. This, as demonstrated by experiments, permits the attainment of the particularly favorable results. Preferably, the width of the shaft extending parallel to the end walls amounts to 1.1 to 1.3 times the height of the piled-up material along the side walls interconnecting the end walls. Also, the height of the piled-up material along the side walls of the discharge collector amounts preferably to 0.6 to 0.8 times the height of the pile in the shaft.
Advantageously, the shaft and the discharge collector each are essentially rectangular in a horizontal cross section and also, in the shaft and the discharge collector two mutually opposing side walls each form end walls, which in associated pairs are in alignment one above the other. Such embodiments provide for a particularly simple construction of the apparatus.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic sectional elevational view of a preferred embodiment of the invention.
FIG. 2 is an enlarged detail of FIG. 1.
FIG. 3 is a sectional view taken along the line III--III of FIG. 2.
FIG. 4 is a sectional view like FIG. 3 showing another embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Turning now to FIG. 1, a dust chamber 2 is in sealing relationship with the upper discharge end of a rotary tube kiln 1 operated in countercurrent. Gas pipes 4 lead from the upper region of the dust chamber 2 to a preheating apparatus 3. A material inlet pipe 5 has a lower end opening into the kiln 1 and is subdivided into three upwardly extending branches 6 which are connected to discharge apertures 7 of the preheating apparatus 3 at its underside. A closable emergency chimney 8 is connected to the gas pipes 4. As indicated by arrows, the flue gases leaving the rotary tube kiln 1 first flow into the dust chamber 2 and then proceed, by way of the gas pipes 4, into the preheating apparatus 3, leaving the latter by way of a gas outlet pipe 9 connected to the preheating apparatus 3 in an upper zone thereof.
The preheating apparatus 3 in its upper region comprises an upwardly closed and downwardly open shaft 10 which has a rectangular horizontal cross-sectional outline. The preheating apparatus has, in its upper region above the piled-up material, lateral connections for the gas discharge pipe 9. A charging chute 11 passes from above downwardly into the shaft 10 for introducing the material to be heated, primarily small-size granular ore having a grain size of 5 to 25 mm or pellets having a grain size of 6 to 20 mm. Below the shaft 10, in symmetry therewith, a chamber 12 is provided which too, has a horizontally rectangular cross-sectional outline and which, as also seen in FIGS. 2 and 3, projects laterally in relation to the shaft 10 on two opposite sides 13. The other side walls of the chamber 12 form end walls 14 and lie with the corresponding end walls 15 of the shaft 10 in a common vertical plane. Two vertical walls 16 are provided symmetrically in the chamber 12 which form a discharge collector 17 jointly with a portion of the end walls 14. In the center of the discharge collector 17 or the chamber 12 there is arranged a prismatic insert 18, which flares downwardly from a pointed top and which extends transversely to the longitudinal dimension of the chamber 12, symmetrically thereto, from one end wall 14 to the opposite end wall 14. The chamber 12 moreover comprises a flat bottom 19 which, if required, may be provided with cooling devices. The bottom 19 at the same time constitutes the lower confines of the discharge collector 17 and comprises the discharge apertures 7.
A slider device 21 driven by a motor 20, generating back and forth movements, comprises a slider rod 22 connected to the motor 20 and extending above the bottom 19 parallel thereto. To the rod 22 there are attached two sliders 23 extending between the end walls 14 and lying on the bottom 19 at a distance to one another corresponding approximately to half the distance of the two walls 16 from one another. The discharge apertures 7 have a slot-shaped configuration and extend parallel to the walls 16. One of the discharge apertures 7 is centrally arranged below the insert 18 and two other discharge openings 7 are each situated slightly laterally externally of the walls 16. The stroke of the slider device 21 is so set that each of the sliders 23 is moved back and forth between two adjoining discharge apertures 7. The slider device, if necessary, is water-cooled in the same manner as the bottom 19. The walls 16 are spaced from the bottom 19 by a distance corresponding approximately to the width of the discharge apertures 7. This results in the formation of gas inlet apertures 24 which at the same time also serve as the outlet for the heated material to be discharged by the sliders 23. The lower end of the prismatic insert 18 is also at a distance from the bottom 19, resulting similarly in the formation of two connecting apertures to the central discharge aperture 7 which thus can similarly be fed with material by the two sliders 23.
The walls 16 are each at a distance from the upper sides of the chamber 12, whereby passages 25 are formed for an adequately large gas feed into the material undergoing treatment. The base of the material cone emerging from the shaft 10 extends close to the upper edge of the walls 16. The distance A between the two walls 16 amounts to 1.55 times the distance B between the two opposite side walls of the shaft 10 by which the end walls 15 of the shaft 10 are interconnected. Because the end walls 15 and 14 are superposed and the top edge of the prismatic insert 18 is at the same level as the upper edges of the walls 16, the cross-sectional area in that region also amounts to 1.55 times the open cross-sectional area of the shaft 10. The height H of the shaft 10 which extends from its lower end to the level up to the highest location where the material is piled up along the side walls, is so set by the level adjustment of the rectangular feed chute 11 extending between the end walls 15 that B=1.2 H. The height of the material pile along the walls 16 of the discharge collector (measured from the bottom 19) amounts to 0.7 H.
The flue gas of the rotary tube kiln which has a temperature of 800° to 1000° C. is fed into the preheating apparatus 3 by way of gas pipes 4 connected by appropriate inlet nipples to the outer side walls of the chamber 12. Approximately nine-tenths of the flue gas enters the material pile by way of the apertures 25 and from there the gas flows into the shaft 10. The remaining one tenth passes through the lower gas feed apertures 24 into the discharge collector 17 and also flows through the material from below in an upward direction. From the shaft 10 the gas emerges at a temperature of 150° to 300° C. and by way of the gas discharge pipes 9 enters into an after-connected dust filter. The withdrawal of the gas is effected by way of a suction fan. The gas velocity can be so adjusted by the advantageous configuration of the preheating apparatus 3 that it is kept far below the so-called fluidization point at which the solid particles become entrained. An amount of 1 Nm 3 per kg of ore or pellets was found to be an adequate gas volume to be employed for the preheating procedure. That portion of the rotary kiln flue gases, usually the major portion, which is not required for preheating the material, can be utilized for other purposes.
At least those walls of the preheating apparatus which are contacted by hot material are lined with a suitable ceramic material. An embodiment of a water-cooling arrangement for the slider device 21 is shown in FIG. 2. For this purpose a flexible hose 26 of a feeder pipe 28 which is connected to a supply of cooling water is joins to the hollow slider rod 22 near its end adjacent to the motor 20. A similar flexible hose 27 connected to the collecting tank of the water supply is attached to the other end 29 of the rod 22.
Turning now to FIG. 4, there is illustrated a preheating apparatus 3' having the same dimensions as the apparatus 3 excepting the distance between its end walls 14 and 15 which correspond to respective walls 14' and 15' of apparatus 3'. The other parts of the apparatus 3' which are also similar to those of apparatus 3 are provided with the same numerals but marked with a prime sign. Thus, the apparatus 3' also comprises side walls 13' and vertical walls 16', and in its upper region a shaft 10' and a charging chute 11'. Between the side walls 13' and the side walls of the shaft 10' is positioned a partition 30 extending over the entire vertical cross section of the apparatus until the top region of shaft 10'. The partition 30 has at opposite sides vertically extending recesses 31 and 32 in which the ends of respective wall portions 16' and 16" are inserted. The other ends of the wall portions 16' and 16" are inserted in similar recesses in each of the end walls 14'. Two opposite triangular recesses 33 and 34 are arranged at the partition 30 in its central region which adapt the ends of the prismatic respective inserts 18' and 18. Each of the side walls 13' as well as each of the walls of the shaft 10' have three vertically extending recesses 35 and 36, paired off for adaption of the partition 30 in three different positions. To place the partition 30 in another position, the detachable upper part of apparatus 3' comprising the shaft 10' and the upper walls of the chamber 12' is removed and simultaneously the wall portions 16' and 16" and the prismatic inserts 18' and 18" are replaced by other such parts having the respective fitting length. Thus the throughput of the apparatus can be easily adapted to different demands in practice. The number of gas inlet pipes 4' in the walls 13' depends on the gas volume required. As discharge apertures serve several flaps (not shown) arranged at the underside of apparatus 3' from which only the needed number is operated.
It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims. | An apparatus for preheating granular ore includes a shaft defined by vertical walls, an inlet chute disposed above the shaft for introducing the ore thereinto by gravity, an ore discharge collector situated underneath the shaft for receiving preheated ore therefrom, and an arrangement for passing heating gases upwardly in the shaft. The discharge collector has vertical side walls and further, there is provided an insert situated in the discharge collector and extending generally horizontally thereacross. The insert has a downwardly widening configuration. A discharge device is disposed at a lower end of the discharge collector. | 5 |
GENERAL TECHNICAL FIELD
[0001] The invention relates to radio navigation with satellites, notably to satellite radio navigation of the GNSS (<<Global Navigation Satellite Systems>>) type, and more particularly of the GPS (<<Global Positioning System>>), Galileo, GLONASS (<<Global Navigation Satellite System>>).
STATE OF THE ART
[0002] With satellite radio navigation, it is possible to obtain the position of a receiver by a method close to triangulation. The distances are measured from signals sent by satellites.
[0003] More specifically, a receiver for positioning via satellites notably allows delivery of a set of integrated pseudo-velocities or dopplers, each representing the projection on the axis connecting the receiver to each satellite with view to obtaining the relative velocity vector between the receiver and said satellite.
[0004] The signals transmitted by the satellites are formed by modulating the carrier of the signal with a spreading code. Thus, the satellite signals allow two types of measurements for localizing the receiver. Further, the modulation of the carrier with a spreading code extends the spectrum in the spectral band, which increases the resistance of the system to interference. And, additionally, this gives the possibility of disassociating the satellites (by using a different code for each satellite in the GPS case).
[0005] The first type of measurement uses the code of the received signal. The measurements based on the code, unlike the ones based on the carrier (see below) are not ambiguous, since the receiver is capable of evaluating the code period integer between the satellite and the receiver. But the measurements based on the code are much less accurate than those based on the carrier.
[0006] The second type of measurement is a measurement based on the carrier of the receiver. The measurements based on the carrier are accurate but ambiguous. Indeed, the receiver is only capable of evaluating the phase of the carrier, therefore the number of wavelengths between the satellite and the receiver remains unknown: there is therefore an ambiguity which has to be removed.
[0007] In order to carry out both of these types of measurements, the receiver acquires and tracks the received signal. For this, it generates replicas of the code and of the carrier, so called local replicas, which it correlates with the received signal. As the code and the carrier are inconsistent pieces of information, the generations of the code and carrier replicas are subordinated to two distinct loops.
[0008] The carrier loop is generally a phase-locked loop (PLL). The code loop as for it generally includes a double correlation allowing evaluation of the shift between the local code and the received code which corresponds to a difference of measurable energies.
[0009] The receiver uses both of these loops in order to obtain unambiguous accurate measurements.
[0010] In a first phase, a so-called acquisition phase, the receiver operates in an open loop for seeking the received signal by testing several position and velocity assumptions on the local code and on the local carrier. Each control loop is closed when the uncertainty on its input (position for the code and frequency for the carrier) becomes less than the field of application of the discriminant of the loop.
[0011] Thus, both loops are complementary during the phase for tracking the received signal: the carrier loop provides accuracy while the code loop provides robustness.
[0012] However, a source of a feedback error of the carrier loop is due to the crossing of the ionosphere by the waves from the satellites.
[0013] Such inaccuracies cause cycle jumps on the carrier loop, and therefore measurement errors without necessarily causing unlocking of the carrier loop so that there is no re-locking step of the carrier loop: the navigation solution is therefore erroneous.
PRESENTATION OF THE INVENTION
[0014] The invention allows the aforementioned drawbacks to be overcome.
[0015] For this purpose, according to a first aspect, the invention relates to a method for tracking the carrier phase of a signal received from a satellite with a carrier by means of a carrier phase-locked loop, said signal being acquired by a navigation system of the carrier which comprises a localization receiver by radio navigation and a self-contained unit, the receiver being adapted so as to acquire and track the phase of the carrier of the signal stemming from the satellite.
[0016] The method comprises the following steps:
determining a closed-loop control error of the carrier phase loop, said closed-loop control error being determined between two sampling instants and corresponding to a first phase deviation; determining a variation of acceleration of the carrier between both sampling instants by means of a self-contained unit; projecting the variation of acceleration on a satellite-receiver view axis in order to obtain a second phase deviation; comparing the first and second deviations in order to detect an error on the measurement of the carrier phase tracked by said carrier phase loop.
[0021] The method according to the invention may further include either one of the following aspects:
the variation of acceleration of the carrier is obtained by means of a numerical model implemented in a module of the navigation system; the variation of acceleration of the carrier is determined by means of an inertial unit of the navigation system; the comparison consists of determining inconsistency of the first deviation with the second deviation; the inconsistency is integrated over a sliding period with a duration of the order of one to five times a time constant of a filter of the carrier phase loop and then compared with a threshold, typically λ/4, the method comprises a step for generating a replica signal of the received signal from the phase deviation {δγ n ·δt 2 } projected stemming from the self-contained unit; it comprises a step for determining a navigation solution from integrated dopplers stemming from the generated replica signal, if the inconsistency is greater than the threshold, typically of the order of λ/4, the method comprise a step for correcting the integrated dopplers required for the navigation solution, the correction consists of adding a term k·λ/2 to said integrated dopplers wherein k is a relative integer such that the absolute value of the integrated inconsistency is less than a threshold, the threshold being typically of the order of λ/4; it comprises a step for determining a navigation solution from the corrected integrated dopplers; the comparison consists of calculating an inconsistency term defined in the following way:
[0000]
λ
2
π
·
{
δϕ
n
}
rectified
-
{
δγ
n
·
δ
t
2
}
projected
[0000] wherein {δφ n } rectified is the first phase deviation and {δγ n ·δt 2 } projected is homogeneous to a distance corresponding to the second phase deviation and λ is the wavelength associated with the carrier frequency of the received signal.
[0030] According to a second aspect, the invention relates to a navigation system comprising means for applying a method according to the first aspect of the invention.
PRESENTATION OF THE FIGURES
[0031] Other features and advantages of the invention will become further apparent from the description which follows, which is purely illustrative and non-limiting and should be read with reference to the appended drawings wherein:
[0032] FIG. 1 schematically illustrates a navigation system according to the invention;
[0033] FIG. 2 schematically illustrates steps of the method according to the invention;
[0034] FIG. 3 illustrates in a detailed way a navigation system according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0035] In FIG. 1 , a navigation system on board a carrier, typically an aircraft, to be localized, is illustrated.
[0036] Such a navigation system includes a receiver 10 for localization by radio navigation, preferably a GPS or GNSS receiver. The receiver may be a multi-channel receiver and in this case each channel corresponds to one satellite which transmits a signal received by the receiver 10 .
[0037] The receiver 10 includes a receiving antenna 100 capable of receiving a signal stemming from one or several satellites (not shown).
[0038] The case is considered when the signal received by the navigation system is a GPS signal.
[0039] In a known way, the radio navigation signals transmitted by satellites appear as a carrier modulated by a spread waveform containing a pseudo-random binary code. The modulation of the carrier causes spreading of the spectrum around the frequency of the carrier, the radio navigation signals have a spread spectrum.
[0040] The pseudo-random codes represent an identifier of the signal and therefore of the transmitter satellite.
[0041] Further, certain signals for positioning by satellite may also convey useful data (for example the navigation message) as a binary sequence (at a significantly lower rate than the pseudo-random code) modulating the signal from the carrier modulated by the code.
[0042] In the case of the GPS, the radio navigation signals are transmitted in the frequency bands L 1 , centred on 1575.42 MHz and L 2 , centred on 1227.6 MHz.
[0043] Further, the navigation system of FIG. 1 includes a self-contained unit 20 and a unit 30 for detecting and correcting possible loop control errors. It is specified here that the self-contained unit 20 does not receive any signal from one or more satellites and is consequently autonomous. The measurements which it provides are subsequently distinguished from the other ones by the descriptive term of autonomous.
[0044] The receiver 10 operates in a known way in an acquisition or tracking mode.
[0045] It is considered here that one is in a tracking mode, i.e. that the receiver gives the possibility of providing a navigation solution, from a set of pseudo-distances and of pseudo-velocities or integrated dopplers which allow localization of the carrier.
[0046] It is from these measurements that the navigation solution of the carrier is determined.
[0047] In particular, this is the resolution of a set of equations obtained from the pseudo-measurements. These processing operations will not be detailed subsequently since they are well known to one skilled in the art.
[0048] More specifically, the reception of a radio navigation signal comprises a first demodulation by means of an internal replica of the carrier phase generated in the receiver by an oscillator driven by a carrier phase tracking loop and a second demodulation by means of an internal replica of the form of the spreading code produced by a code tracking loop.
[0049] The control signals of the carrier phase and code tracking loops are used by the receiver for determining the pseudo-measurements, with which the navigation solution may be obtained.
[0050] As this was already mentioned above, the navigation system includes a unit 30 for detecting and correcting closed-loop control errors.
[0051] This unit 30 gives the possibility of applying a method for monitoring the loop for tracking the carrier phase of the signal received from a satellite. Such a method is of course implemented for each channel in the case when the receiver is a multi-channel receiver.
[0052] The object of this method is to detect one or several cycle jumps in the phase of the carrier and to correct them.
[0053] Steps of such a method are schematically illustrated in FIG. 2 .
[0054] In a first step E 1 , a closed-loop control error of the carrier phase loop is determined between two instants. Thus this closed-loop control error is a first phase deviation. This phase deviation allows the carrier phase tracking loop to get back in step.
[0055] This first phase deviation is taken between consecutive samples measured at the output of the carrier phase loop. Such a phase deviation is expressed by δφ n =φ n −φ n-1 wherein n is an index corresponding to the calculation instant.
[0056] In a second step E 2 (which may practically be applied before or in parallel with the first step E 1 described above) a variation of acceleration of the carrier is determined between both instants.
[0057] This variation of acceleration is determined by the self-contained unit 20 of the navigation system.
[0058] According to an embodiment, the self-contained unit 20 may include an inertial numerical model which allows determination of the acceleration variation of the carrier relatively to the satellite.
[0059] Taking into account that the movement of the satellite (the carrier in this case) is mainly governed by Kepler's laws; accordingly, the position of the satellite is determined from the orbital Kepler parameters. The velocity of a satellite is determined by differentiation (preferentially an exact formula) or by differentiation of the position. The acceleration is obtained by differentiation of the velocity.
[0060] According to another embodiment, the self-contained unit 20 is an inertial unit.
[0061] As this is known, an inertial unit mainly consists of two groups of three sensors. The groups of sensors are gyrometers (rotation measurements) and accelerometers (acceleration measurements). The three sensors of each group are oriented in order to capture the movements in space (in three dimensions). Integration of the accelerometric measurements provides the velocity along the axis of each accelerometer, and integration of the velocities provides the position of each accelerometer along its axis. The integrations call for determination of the initialization constants: this is the subject of inertial alignment.
[0062] As the movement of a mobile is arbitrary, the orientation of the axes of the accelerometers varies, therefore it is necessary to project the acceleration measurements in a reference coordinate system: this is the purpose of the gyrometers to determine the rotation of the measurement axes of the accelerometers.
[0063] Thus, in a third step E 3 , the acceleration variation is projected on a satellite-receiver view axis so as to obtain a relevant measurement, this projected acceleration variation representing a second phase deviation.
[0064] The projection of the acceleration variation is homogeneous to meters (m) and as a wavelength is equivalent to 2π radians, it is possible to simply switch from the projected acceleration variation to a carrier phase deviation.
[0065] Next, in a fourth step E 4 , the first and second deviations are compared in order to detect a possible error on the carrier phase tracked by the carrier phase loop.
[0066] The question here is in particular to identify whether the phase deviation allowing the carrier phase loop to be driven is erroneous or inconsistent or else if it is subject to cycle jumps.
[0067] Finally, in a fifth step E 5 , the navigation solution is determined from the phase deviation measured by the carrier loop and optionally corrected from the projected acceleration variation stemming from the measurements carried out by the self-contained unit 20 .
[0068] The radio navigation solution is determined from pseudo-measurements, for example by a least squares algorithm, and applies a phase deviation.
[0069] The comparison E 4 notably consists of determining inconsistency of the first deviation with the second deviation.
[0070] If the determined inconsistency is greater than the threshold, an inconsistency alert may be suppressed, the second phase deviation replaces the first and the determination E 6 of the navigation solution stems from the corrected closed-loop control.
[0071] Alternatively, the determination E 6 of the navigation solution is carried out from corrected pseudo-measurements.
[0072] A detailed scheme of a navigation system is also illustrated in FIG. 3 .
[0073] Like in the diagram of FIG. 1 , a signal of the GPS type is received by a radio navigation antenna 100 .
[0074] At the antenna 100 , the signal is pre-amplified and then filtered, undergoes lowering in frequency and finally undergoes analogue/digital conversion before being processed digitally.
[0075] In a known way, in a tracking mode, a carrier phase loop tracks the carrier phase of the received signal. The carrier phase loop is driven by a local oscillator 18 with which during the tracking of the carrier phase a phase deviation between the local replica and the received signal may be corrected. Indeed, the navigation solution is calculated from the local signal which has to be a quasi-perfect replica of the received signal.
[0076] At the local oscillator 18 , a local replica signal is generated. Such a replica signal is formed in a known way by a carrier (sine wave) modulated with a pseudo-random binary code; it is sampled at a frequency of the order of a few MHz to a few tens of MHz. The frequency of the replica of the carrier is equal to the transmission frequency of the carrier by the satellite (1.57542 GHz in the case of GPS L 1 ), reduced with the frequency lowering by the receiver, or increased by the relative satellite/carrier Doppler component. The purpose of the closed-loop control on the carrier phase is specifically to determine this relative Doppler component. The frequency of the replica of the code is equal to the transmission frequency of the code by the satellite (1.023 MHz in the case of the GPS C/A code), increased by the driving of the code by the carrier (i.e. by the estimated Doppler component by the carrier loop), and increased by the code-carrier inconsistency, object of the code control loop.
[0077] From the received signal and the local signal generated by the local oscillator 18 , a phase channel I and a quadrature channel Q of the correlation product of both signals are determined, channels which will be used subsequently.
[0078] Channel I is in particular the integral of the product of the received signal by the local signal, this integration being carried out at a frequency of the order of a few to a few tens of MHz (see the sampling frequency of the local oscillator 18 ) and on a horizon of 1 ms or an epoch of the C/A code, the channel I then being provided at the output and then reset to zero.
[0079] Channel Q is determined in a similar way to channel I but the local signal has a carrier phase advance of π/2 relatively to the one used for calculating channel I.
[0080] From these two channels I, Q, a carrier loop discriminant is determined 12 . Such a discriminant is obtained by calculating
[0000]
Arctan
(
Q
I
)
.
[0000] From this discriminant, a value of the phase of the carrier φ n is inferred.
[0081] As the received signal includes navigation data coding a piece of information, the carrier phase is rectified 13 , 14 , 15 for removing these data.
[0082] The question is to notably determine 13 , 15 a phase deviation taken between two calculation instants (or else two samples): δφ n =φ n −φ n-1 .
[0083] This phase deviation δφ n will give the possibility of obtaining 14 a rectified phase deviation {δφ n } rectified .
[0084] In particular, if δφ n >π/2 then δφ n is reduced by π while if δφ n <−π/2 then δφ n is increased by π.
[0085] This is therefore a rectified phase deviation δφ n which is used for determining whether there is an ambiguity on the carrier phase.
[0086] It is this phase deviation {δφ n } rectified which is integrated 16 during the whole duration of the servo-control and then filtered by a loop of the third order 17 and then sent to the input of the local oscillator 18 for generating a replica signal of the received signal.
[0087] The error detection and correction module 30 may have to correct an error beforehand.
[0088] To do this, the module 30 receives the phase deviation {δφ n } rectified stemming from the carrier phase loop (dynamics measured by the carrier phase loop) on the one hand and the autonomous dynamics which in fact is an acceleration variation projected on a satellite-carrier view axis.
[0089] The acceleration variation determined by the self-contained unit 20 is obtained either from an inertial model or from an inertial unit 23 .
[0090] Such an acceleration variation is obtained by determining autonomous dynamics processed by a module for integrating the navigation 22 in order to obtain an autonomous measurement and therefore an absolute measurement of the acceleration γ n of the position P n and of the velocity V n .
[0091] The acceleration variation is projected on a satellite-receiver view axis by a projection module 23 .
[0092] From this projection, a therefore autonomous variation of the acceleration projected on a {δγ n ·δt 2 } projected view axis is obtained.
[0093] The acceleration variation is determined over the same calculation period as the one for determining the phase variation at the carrier phase loop.
[0094] In order to detect a possible error, the correction module 30 determines an inconsistency term defined in the following way:
[0000]
λ
2
π
·
{
δϕ
n
}
rectified
-
{
δγ
n
·
δ
t
2
}
projected
[0000] wherein {δφ n } rectified is the first phase deviation, {δγ n ·δt 2 } projected is homogeneous to a distance corresponding to the second projected phase deviation and λ is the wavelength associated with the carrier frequency of the received signal.
[0095] If the term above is greater than the threshold, the measurement of the carrier phase {δφ n } rectified is marred with an error.
[0096] In this case, there are two solutions for suppressing the error.
[0097] The first solution consists of using E 5 the phase deviation obtained from the self-contained unit 20 , {δγ n ·δt 2 } projected for generating the replica signal.
[0098] In that case, the threshold is of the order of 3σ φ n at λ/4 wherein σ φ n is a function of the signal-to-noise ratio.
[0099] It is this replica signal which will be used for measuring the pseudo-velocities or integrated dopplers required for calculating the navigation solution.
[0100] The second consists of correcting E 5 ′ the integrated dopplers by adding to them a term k·λ/2 wherein k is a relative integer such that |inconsistency| integrated <threshold. In particular the inconsistency is integrated over a sliding period with a duration of the order of 1 to 5 times the constant of the filter of the control loop on the carrier. The threshold is of the order of λ/4.
[0101] The first solution is only applicable when the estimation 25 of {δγ n ·δt 2 } projected is available at the calculation instant of the filtering 17 .
[0102] The second solution is applicable in all cases, but becomes mandatory when the first solution is not applicable. In this case, the carrier phase deviation {δφ n } rectified has to be stored in memory so that the calculation of the inconsistency term deals with synchronized (i.e. stemming from the same time period) autonomous and radio navigation measurements. | The invention relates to a method for tracking the carrier phase of a signal received from a satellite by a carrier using a carrier loop of the carrier phase, said signal being acquired by a navigation system of the carrier, said navigation system including a receiver for location by radio navigation, and a self-contained unit, wherein the receiver is suitable for acquiring and tracking the phase of the carrier of the signal from the satellite. | 2 |
RIGHTS OF THE GOVERNMENT
The invention described herein may be manufactured and used by or for the Government of the United States for all governmental purposes without the payment of any royalty.
BACKGROUND OF THE INVENTION
This invention relates to corrosion inhibiting compositions and to a process for inhibiting the corrosion of metals. In particular, this invention relates to a multifunctional inhibitor that provides both anodic and cathodic corrosion inhibition for a broad spectrum of metallic materials and structures in aggressive media such as brine, bilge solution and high-chloride contaminated water.
The financial loss due to the degradative effects resulting from corrosion reactions amounts to billions of dollars annually. In an attempt to combat the problem of corrosion and minimize its economic disadvantages, a U.S. Air Force research effort was initiated to develop improved inhibiting compositions. As a part of this research effort a survey and screening of conventional inhibitor compositions such as the polyphosphates, silicates, orthophosphates, chromates, nitrites, and combinations thereof was undertaken to determine their effectiveness in inhibiting corrosion of aircraft structures. Film-forming inhibitors, such as emulsified or soluble oils, long chain amines, alcohols and carboxylic acids were also studied.
Unfortunately, anodic inhibitors, such as the chromates, may cause accelerated corrosion when in contact with a metal in too low a concentration, such as where the concentration decreases during use. The result may be a metal surface protected in most areas, but giving rise to accelerated corrosion in small, highly anodic areas of the metal surface. On the other hand, a significant advantage of chromate inhibiting formulations is their broad protective ability against general corrosion of many metals and alloys.
For nonchromate systems, a rather complex mixture is required to achieve such broad-based protection. The simple borax-nitrite system is, for example, effective for many steels, but must be complemented by other inhibitors to provide adequate protection for high strength aluminum alloys, particularly in the presence of corrosive contaminants such as sodium chloride.
Other inhibitor systems are applicable only to a limited number of alloys or lack the degree of protection for satisfactory and adequate protection for aerospace and other high performance (high strength, high strength:weight ratio, high fatigue resistance) structural alloys. Still other inhibitor systems have not been found satisfactory for use with high performance alloys in the presence of sodium chloride. Commercial formulations which have been tested on aerospace alloys, such as 7075-T6Al, 2024-T3Al, and 4340 steel, in the presence of sodium chloride in aqueous solutions have ranged from totally ineffective to partially effective in immersion tests.
Toxicity has become an increasingly important consideration in recent years, both with respect to handling of the compounds prior to use, and to the effects of disposal on humans, animals and plants. Consequently, it is necessary to develop substitutes for such popular inhibitors as chromate based formulations and high phosphate based formulations.
A previous study on corrosion prevention of carrier-based aircraft revealed that a considerable savings could be realized in terms of corrosion maintenance by merely rinsing the aircraft with water to remove detrimental particles, such as salt and ash. How, ever, in rinsing aircraft, a very good possibility exists that the water will be trapped in crevices or so-called dry-bay areas. The trapped water, often chemically hard, can cause serious corrosion problems, hence completely jeopardizing the advantage of water rinsing as a corrosion-control method. Therefore, the incorporation of a low concentration of a nontoxic, water-soluble inhibitor into the rinse water becomes a desirable means for improving corrosion resistance.
The value of borax-nitrite as a corrosion inhibitor has long been recognized. Earlier work has shown this combination to be very effective in controlling general corrosion as well as crevice corrosion of high strength steels. However, the borax-nitrite combination was not found to be effective against the corrosion of other ferrous and nonferrous metals and alloys. For example, nitrite inhibitors are more effective at higher pH ranges (e.g., 8-9) than at more acidic levels. Very high pH levels, however, can be deleterious to some aluminum alloys since aluminum is amphoteric, subject to attack by strong basic solutions.
In our copending application Ser. No. 265,734, filed May, 1981, now abandoned we disclose corrosion inhibiting compositions which are biodegradable, contain no chromates, and offer important and unique advantages over chromate-based inhibitor combinations. The compositions are multifunctional, providing both anodic and cathodic protection. The compositions are nontoxic, low in cost, soluble in aqueous solution and provide protection for a broad spectrum of metallic structures. Concentration of the inhibitor composition in aqueous rinsing solution is nominally 0.3 to 0.5 percent, by weight, of the rinse solution. The inhibiting compositions include sodium borate, sodium nitrite, sodium hexametaphosphate, sodium metasilicate, sodium nitrate and mercaptobenzothiazole in a predetermined range of concentrations.
We have found that the effectiveness of the compositions disclosed by us in the aforesaid application Ser. No. 265,734 can be improved by the addition thereto of selected surfactant compounds. These improved corrosion inhibiting formulations are particularly useful in very aggressive environments containing chloride ion in excess of 1000 ppm (0.1 weight percent). Such high levels may be found in coastal areas and in urine, which contains approximately one weight percent sodium chloride, or about 6000 ppm of chloride ion.
Accordingly, it is an object of the present invention to provide an improved multifunctional corrosion inhibiting composition.
Other objects and advantages of the present invention will be readily apparent to those skilled in the art from a consideration of the following disclosure.
SUMMARY OF THE INVENTION
In accordance with the present invention there is provided an improved corrosion inhibiting composition consisting essentially of a mixture of an alkali metal borate, an alkali metal nitrite, an alkali metal nitrate, an alkali metal metasilicate, an alkali metal phosphate, mercaptobenzothiazole (MBT), at least one selected surfactant. In some formulations, zinc sulfate and benzotriazole (BT) are also required. The alkali metal can be either sodium or potassium.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings;
FIG. 1 illustrates the anodic-polarization behavior of type 7075-T6 aluminum in local top water, distilled water, 0.1M NaCl and the basic inhibitor solution;
FIG. 2 illustrates the effect of increasing chloride concentration upon the breakdown of passivity of type 7075-T6 aluminum;
FIG. 3 illustrates the effect of increasing chloride concentration upon the breakdown of passivity of type 4340 steel;
FIG. 4 illustrates the effect of adding a surfactant to an inhibitor solution in preserving passivity of type 7075-T6 aluminum;
FIG. 5 illustrates the effect of adding a surfactant to an inhibitor solution in preserving passivity of type 4340 steel;
FIG. 6 illustrates the anodic polarization of type 7075-T6 aluminum in natural and in synthetic urine; and
FIG. 7 illustrates the effects of adding the inhibitor composition of this invention for preserving the passivity of various metals in synthetic urine solution.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The amounts of each component of the inhibiting composition of this invention are given in Table I, below.
TABLE I______________________________________Concentration in aqueoussolution (weight percent) Concentration of DryComponent Broad Preferred Ingredients (percent)______________________________________Borate .20-2.00 0.25-1.40 68.0-70.0Nitrite .04-.25 .05-.20 8.5-14.0Nitrate .04-.50 .05-.40 13.5-17.5Silicate .0015-.05 .005-.04 0.5-1.75Phosphate .0025-.025 .005-.02 0.8-0.9MBT .0008-.015 .003-.012 0.25-0.5BT .0008-.015 .003-.012 0.25-0.5ZnSO.sub.4 .003-.06 .005-.05 1.0-2.0Surfactant .006-.03 .0050-.025 1.0-2.0______________________________________
The surfactant is a selected anionic or nonionic surface active material. The selected surfactants employed in the corrosion inhibitor of the present invention are, in general, proprietary materials. Table II, below, lists the surfactants employed according to the present invention by (1) an arbitrary designation, (2) a brief description of the composition of the surfactant, (3) the commercial name of the surfactant, and (4) the source for such surfactant.
TABLE II__________________________________________________________________________Proprietary Surface Active Agents Commercial.sup.(3)Designation.sup.(1) Description.sup.(2) Name Source.sup.(4)__________________________________________________________________________SAR Sodium Dodecylbenzene Sulfonate Richonate The Richardson Company Des Plaines, IllinoisSAD Sodium salt of Phosphonic acid Dequest Monsanto Company St. Louis, MissouriSAB Corrosion inhibitor (commercial Boeshield T-9 Oxy Metal Industries formulation) with complex Corp. sulfonate compound Madison Heights, MISAM Dialkyl alkyl phosphonate Mobil Chemical Company Phosphorous Division Richmond, VirginiaSAP High molecular weight phosphate Monsanto Company St. Louis, MissouriSAT Octylphenoxy polyethoxy ethanol Triton X-114 Rohm and Haas Co. Industrial Chemicals - NA Philadelphia, PennsylvaniaSAO High molecular weight calcium 100 Oil The Southland Corp. sulfonate Arthur C. Trask Chemical Division Summit, IllinoisSAE High molecular weight Barium Estersulf The Southland Corp. sulfonate Arthur C. Trask Chemical Division Summitt, IllinoisSAG Sodium salt of a complex Phosphate GAF Corporation ester New York, New York__________________________________________________________________________
Referring now to the drawings, FIG. 1 shows the anodic polarization behavior of type 7075-T6 aluminum in distilled water, local tap water, a 0.1 molar solution of sodium chloride and local tap water containing the corrosion inhibitor disclosed in the aforementioned application Ser. No. 265,734. This figure illustrates a very high corrosion current and breakdown in passivity in tap water and in 0.1M NaCl, as well as illustrating the protection afforded by the aforesaid corrosion inhibitor. FIG. 2 illustrates the effect of increasing chloride concentration upon the breakdown of passivity of type 7075-T6 aluminum. FIG. 3 illustrates a similar type of behavior with type 4340 steel.
FIGS. 4 and 5 illustrate the effect of adding 125 ppm of sodium dodecylbenzene sulfonate (SAR) to solutions of increasing chloride concentration, each containing the basic inhibitor mentioned above. A comparison of FIG. 4 with FIG. 2, although not strictly comparable, clearly indicates the increased protection afforded by the addition of sodium dodecylbenzene sulfonate to the basic inhibitor formulation. A more direct correlation is seen by reference to FIGS. 5 and 3.
FIGS. 6 and 7 illustrate the anodic polarization behavior of various metals in a synthetic urine solution. The composition of the synthetic urine is given in Table III below.
TABLE III______________________________________Ingredients of Synthetic Urine(Wt in gm/liter)______________________________________urea 20.605-hydroxyindoleacetic acid 0.0045uric acid 0.052glucuronic acid 0.431oxalic acid 0.031citric acid 0.462glycolic acid 0.042creatine 0.0721guanidinoacetic acid 0.027formic acid 0.013glucose 0.072ammonium sulfate 4.00potassium phosphate 0.175potassium chloride 0.0100potassium bromide 0.008sodium chloride 10.00p-cresol 0.087creatinine 1.500acetone 0.0001hydroxyquinoline-2 carboxylic acid 0.0028potassium sulfate 0.134______________________________________
FIG. 6 illustrates that the corrosive behavior of synthetic urine closely approximates that of natural urine. FIG. 7 illustrates the anodic polarization behavior of type 7075-T6 aluminum, type 4340 steel, copper and brass in synthetic urine and in synthetic urine inhibited by the multifunctional inhibitor formulation containing 125 ppm of sodium dodecylbenzene sulfonate.
More specific inhibitor formulations are given in Tables IV and V below. All amounts are given in weight percent (in aqueous solution).
TABLE IV______________________________________ FormulationComponent 1 2 3 4______________________________________Borate 0.35 0.35 0.35 0.35Nitrite .20 .20 .20 .20Nitrate .20 .20 .20 .20Silicate .01 .01 .01 .01Phosphate .0125 .005 .005 .005MBT .0065 .005 .005 .005BT .005 .005 .005 .005SAR, SAE .0125 -- .0075 --SAD .0165 -- -- --SAT -- .01 -- --SAB -- -- -- .025ZnSO.sub.4 .004 .02-.04 .01 --______________________________________
TABLE V______________________________________ FormulationsComponent 5 6 7______________________________________Borate 0.25 0.35 1.40Nitrite .05 .05 .20Nitrate .05 .10 .40Silicate .002 .01 .04Phosphate .003 .005 .02MBT .001 .003 .012BT -- .003 --SAR .0075 .0075 .0075______________________________________
Formulation 1 is preferred for use where the concentration of chloride is very high, e.g., brine. Formulations 2 and 3 are recommended for use in aggressive solutions such as are found in the bilge areas of aircraft. Formulation 4 will provide protection in high chloride contaminated water, i.e., up to about 1 weight percent NaCl.
Formulation 6 is a preferred formulation for general purpose use. It is effective where little or no dilution is expected during use and low concentrations of chloride and other aggressive reactants are present, i.e., up to about 100 ppm chloride ion. Formulation 5 is effective in situations where no dilution is expected and the concentration of chloride ion or other aggressive reactant is very low. Formulation 7 is for contact inhibitors to form a protective surface layer during immersion.
The concentrations of the various components can be varied by about 20% for conditions where dilution in use is expected.
In Table VI, below, the representative results of tests with several experimental formulations are summarized. These immersion tests were carried out on type 7075-T6 aluminum and type 4340 steel in 1M NaCl solutions.
TABLE VI__________________________________________________________________________Immersion Test Results Time ofInhibitor pH Exposure Surface AppearanceNo wt % in 1M NaCl Initial Final Specimen (weeks) (Visual Observation) Remarks__________________________________________________________________________1 0.35 Borate + 0.2 Nitrate + 7.90 7.90 Al 2 Several pits Better 0.2 Nitrite + 0.01 Silicate + Steel 2 Clean & shiny; few pits Inhibitor 50 ppm Phosphate + 30 ppm required MBT + 100 ppm SAO2 0.35 Borate + 0.6 Nitrate + 8.30 8.20 Al 1 Clean Better 0.6 Nitrite + 0.01 Silicate + 6 Few pits Inhibitor 50 ppm Phosphate + 30 ppm Steel 1 Clean, Few fine pits required MBT 6 Many pits at edge3 0.35 Borate + 0.2 Nitrate + 8.20 8.15 Al 4 Clean & shiny Improve- 0.05 Nitrite + 0.01 Silicate + 16 Clean & shiny ment 50 ppm Phosphate + 50 ppm Steel 4 Clean, pits required MBT + 100 ppm SAE 16 Clean, several pits4 0.35 Borate + 0.2 Nitrate + 8.20 8.25 Al 2 Dull, patches Better 0.05 Nitrite + 0.01 Silicate + of Corrosion Inhibitor 50 ppm Phosphate + 50 ppm Steel 2 Several pits required SAM5 0.35 Borate + 0.1 Nitrate + 8.80 8.70 Al 2 Clean Fair 0.05 Nitrite + 0.01 Silicate + 10 Clean, few corrosion 50 ppm Phosphate + 50 ppm streaks MBT + 50 ppm SAP + 100 Steel 2 Clean ppm SAE 10 Clean, pits6 0.35 Borate + 0.2 Nitrate + 8.15 8.10 Al 2 Clean & shiny Excellent 0.2 Nitrite + 0.01 Silicate + 12 Clean & shiny inhibition 125 ppm Phosphate + 60 ppm Steel 2 Clean & shiny MBT + 100 ppm SAR + 210 12 Clean & shiny, two ppm SAD + 40 ppm ZnSO.sub.4 fine pits7 0.35 Borate + 0.2 Nitrate + 8.15 8.20 Al 2 Clean & shiny Excellent 0.2 Nitrite + 0.01 Silicate + 8 Clean & shiny Inhibitor 50 ppm Phosphate + 75 ppm Steel 2 Clean & shiny SAT + 500 ppm ZnSO.sub.4 8 Clean & shiny8 0.35 Borate + 0.2 Nitrate + 9.35 9.20 Al 2 Clean & shiny Excellent 0.2 Nitrite + 0.01 Silicate + 8 Clean & shiny Inhibitor 50 ppm Phosphate + 100 ppm Steel 2 Clean & shiny MBT + 75 ppm SAR + 100 8 Clean & shiny, one ppm ZnSO.sub.4 fine pit9 1% SAB 6.25 6.25 Al 4 Clean & shiny Better 24 Badly corroded Inhibitor Steel 4 Clean & shiny required 24 Badly corroded10 0.35 Borate + 0.2 Nitrate + 8.15 8.20 Al 2 Clean & shiny Excellent 0.2 Nitrite + 0.01 Silicate + 8 Clean & shiny Inhibitor 50 ppm Phosphate + 100 ppm Steel 2 Clean, one pit MBT + 250 ppm SAB 8 Clean & shiny__________________________________________________________________________
In Table VI above and in Table VII, below, the term borate refers to sodium borate tetrahydrate, nitrate to sodium nitrate, nitrite to sodium nitrite, silicate to sodium metasilicate pentahydrate, and phosphate to sodium hexametaphosphate.
In Table VII below, the representative results of tests with several experimental formulations are summarized. These tests were carried out on type 7075-T6 aluminum, type 4340 steel, and brass in synthetic urine solution, and in a mixture of synthetic urine and coffee.
TABLE VII__________________________________________________________________________ Time ofInhibitor wt % in pH Exposure Surface AppearanceNo synthetic urine* Initial Final Specimen (weeks) (Visual Observation) Remarks__________________________________________________________________________11 0.35 borate + 0.2 nitrite + 9.35 9.25 Al 2 Clean & shiny Excellent 0.2 nitrate + 0.01 silicate + 8 Clean & shiny 100 ppm ZnSO.sub.4 + 50 ppm Steel 2 Clean & shiny phosphate + 75 ppm SAR 8 Clean & shiny, one fine pit12 0.35 borate + 0.2 nitrite + 8.50 8.50 Al 4 Clean & shiny Excellent 0.2 nitrate + 0.01 silicate + Steel 4 Clean & shiny 0.01 phosphate + 0.01 Brass 4 Clean & shiny MBT + 125 ppm SAR13 0.35 borate + 0.2 nitrite + 8.15 8.15 Al 2 Clean & shiny Excellent 0.2 nitrate + 0.01 silicate + 12 " 125 ppm phosphate + 60 ppm Brass 2 " MBT + 40 ppm ZnSO.sub.4 + 12 " 100 ppm SAR + 200 ppm Steel 2 " SAD 12 Clean & shiny, three fine pits14 0.35 borate + 0.2 nitrite + 8.15 8.15 Al 2 Clean & shiny Excellent 0.2 nitrate + 0.01 silicate + 8 " 50 ppm phosphate + 100 ppm Brass 2 " MBT + 250 ppm SAB 8 " Steel 2 Clean, one pit appear- ing on one surface 8 Clean & shiny15 0.35 borate + 0.2 nitrite + 8.15 8.00 Al 4 Clean & shiny Excellent 0.2 nitrate + 0.01 silicate + 32 " 50 ppm MBT + 500 ppm Brass 4 " ZnSO.sub.4 + 75 ppm SAT 32 " Steel 4 " 32 "__________________________________________________________________________ *Except Run 15 which was 50% synthetic urine and 50% coffee.
The corrosion inhibiting formulations of this invention may be used in aqueous solution as rinse-type inhibitors and as immersion-type inhibitors. The corrosion inhibitor may be compounded dry, and stored in bulk for later solution in water. In the dry form, the corrosion inhibitor may be incorporated from 20 to 50 weight percent, preferably about 30 weight percent, into a commercial soap formulation, e.g., a handsoap, for use in the lavatory of an aircraft or ship.
The corrosion inhibitor may be incorporated into a coating composition, such as a paint primer by encapsulating the inhibitor formulation with a cellulosic or nylon or other suitable encapsulating material using conventional encapsulating techniques, and incorporating 20 to 50 weight percent, preferably about 30 weight percent, of the encapsulated inhibitor into a conventional coating composition. The corrosion inhibiting components may be released if the coated surface is scratched or otherwise physically damaged.
Various modifications can be made to the above described invention. | A multifunctional corrosion inhibitor consisting essentially of an alkali metal borate, an alkali metal nitrate, an alkali metal nitrite, an alkali metal metasilicate, an alkali metal phosphate, mercaptobenzothiazole and at least one selected surfactant. | 2 |
BACKGROUND
[0001] 1. Field of Invention
[0002] The present disclosure relates to teaching methods and apparatus, and more particularly to teaching methods and apparatus for children.
[0003] 2. Background
[0004] In today's society, daycare centers and pre-school centers have proliferated, with more children being introduced to formal learning and studying at an early age. It is very common for children to be placed in a school-like setting, such as preschool, pre-kindergarten and kindergarten (ages 3 through 6). At such early ages, a child's attention span is short, there is little personal history of learning to draw from, and a child may be wary or even frightened at being left alone with relatively unknown adults and other children. Consequently, major challenges are presented to develop methods and apparatus for teaching young children and for motivating them to learn. Moreover, as children are placed in new surroundings, there is a challenge to find ways to put them at ease and to help them feel at home in new surroundings.
[0005] Many children have special needs, either because of physical or mental handicaps, or because of emotional problems. These special needs can interfere and hamper the teaching process, and heighten frustrations. Such needs increase the importance of developing good teaching methods and apparatus, in order to reach such children and help them to learn.
[0006] One of the best ways to reach children and maintain their interest has been to appeal to their curiosity, creativity and imagination, as well as their desire to play and have fun. One example is shown in U.S. Pat. No. 5,655,910 (Troudet), in which children are taught games and creative concepts to associate hands, digits, indicia and characters in order to enhance teaching keyboarding. In U.S. Pat. No. 5,980,354 (Prest), storyboard toys are utilized to nurture learning through associating various storyboard pieces with characters and figures.
[0007] Accordingly, new methods and apparatus are needed to appeal to the imagination and creativity of children and to peak their curiosity. Moreover, activities are needed that engage children in teaching activities while incorporating playful activities and having fun. In addition, a learning environment is needed that gives children a feeling of comfort and puts them at ease. Further, teaching methods and apparatus are needed to overcome the barriers of children with special needs and to stimulate their interest.
SUMMARY
[0008] In one implementation of the present disclosure, a teaching method and apparatus are provided for using a workshop and a classroom to assist in teaching at least one child about a topic. The method comprises reading a writing about the topic with or to the child in the classroom, creating an item in the workshop that was mentioned in the story, and discussing the created item with the child.
[0009] In another implementation of the present disclosure, a teaching method and apparatus are provided for use in motivating children to learn, including providing a simulated village having a plurality of shops, providing at least one classroom in the simulated village, providing at least one workshop in one of the plurality of shops, and providing an activity for the children in the workshop related to a topic studied in the classroom.
[0010] In another implementation of the present disclosure, a teaching method and apparatus are provided for use in motivating children to learn in a classroom, including providing a fantasy-type structure near or in the classroom, providing an area in the fantasy-type structure to accommodate at least one child, and allowing access through an entry way to the area.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The above-mentioned features and other features and advantages of this disclosure will become more apparent and the disclosure will be better understood by reference to the following description of an exemplary implementation taken in conjunction with the accompanying drawings, wherein:
[0012] FIG. 1 is a generalized pictorial view of a childrens' school environment in the form of a simulated village or fairy tale setting;
[0013] FIGS. 2, 3 and 4 are pictorial views of the fronts of shops and cottages in the simulated village shown in FIG. 1 ;
[0014] FIGS. 5A and 5B are pictorial views of a simulated tree in the simulated village of FIG. 1 ;
[0015] FIG. 6 is a pictorial view of a classroom according to one implementation of the present disclosure;
[0016] FIG. 7 is a pictorial view of a kitchen workshop in the village shown in FIG. 1 ;
[0017] FIG. 8 is a pictorial view of a tailor workshop in the village shown in FIG. 1 ;
[0018] FIG. 9 is a pictorial view of a wood workshop in the village shown in FIG. 1 ; and
[0019] FIG. 10 is a pictorial view of a science workshop in the village shown in FIG. 1 ;
[0020] Throughout the drawings, identical reference numbers may designate similar, but not necessarily identical, elements. The examples herein illustrate selected implementations of the disclosure in certain forms, and such exemplification is not to be construed as limiting the scope of the disclosure in any manner.
DETAILED DESCRIPTION
[0021] In the present description, methods and apparatus are disclosed that involve one or more workshops as tools to supplement teaching of concepts and stories to children in the classroom. If a story is being taught to the children, a workshop may be used to act out the story or to create and/or use various key items in the story. If a concept is being taught to the children, a workshop may be utilized to enable the children to have a hands-on experience with the concept being discussed. These workshops provide opportunities for the children to learn basic skills that are needed throughout life. Such workshops may also open up direction to future career paths and many growth possibilities.
[0022] In addition, the present description includes methods and apparatus for placing the children in a relaxed and stimulating environment. A simulated village provides a feeling of safety and nurturing, where children can discover their unique potential. The village is associated with the classroom in various ways. For example, the classroom can be disposed as a part of the simulated village to give a sense of community and belonging. In addition, the simulated village may have fantasy qualities, such as a village that appears to be out of a fairy tale, in order to stimulate interest and creativity and to place the children at ease.
[0023] Another characteristic of the present description includes methods and apparatus for utilizing a simulated structure, such as a simulated tree, to enhance the interest of the children. The simulated tree can be used as a symbol of knowledge, life and growth, as well as of being a protective umbrella for the children and a reminder of their potential. In addition, the tree may have a hollow trunk, with a door that allows access to a room in the trunk. The room can be used as a reward for achievement or good behavior, or can be a time-out place for calming down from excitement or a disturbance.
[0024] Looking now at FIG. 1 , a children's school environment is shown in the form of a European or fairy tale village 10 . The village 10 is comprised of a village square 11 surrounded by several simulated shops and cottages, such as shop front 12 and cottage 14 , which are reminiscent of shops or cottages in fairy tales. A large simulated tree 16 is situated in a central position in the village 10 to provide a symbolic presence. Classrooms 18 , 19 and 20 may be disposed near the tree Other areas, which may include workshops, such as those discussed with reference to FIGS. 7-10 may also be provided. These workshops may be separate from the classrooms.
[0025] As seen in FIG. 2 , a shop front 22 has unique fantasy-like features, including gables 24 with picturesque windows 26 , window boxes with flowers 30 below gables 24 , a bay window 28 , and a bear statue 32 holding a flower tin. Similarly, in FIG. 3 , a shop front 34 includes rounded gables 36 with quaint windows 38 and a window box 40 . A clock 42 hangs above the shop front 34 , and another window box 44 is located in the front of the shop. Door lamps 46 are located on either side of a doorway 48 leading into the shop.
[0026] FIG. 4 shows another picturesque scene in village that is reminiscent of a quaint street setting. A shop window casing 52 is disposed next to a tower 54 which is adjacent to a lattice-formed window 56 . An old-fashioned bench 58 is positioned near a street lamp 60 in front of windows 62 and 64 for a shop or classroom. Decorative lighting 66 and a simulated roof fence 68 add to the atmosphere.
[0027] Looking now at FIGS. 5A and 5B , the simulated tree 16 is shown in more detail. The tree may be made of fiberglass or other durable material. It includes several sturdy branches 70 that support various lights 74 thereon. A few steps 76 lead up to a door 78 in the tree trunk 80 , having a small round window 82 therein. Tree 16 is surrounded by windows 18 , 19 (not shown) and 20 looking in on children's classrooms. Door 21 leads into one of the classrooms. An imitation picket fence 84 is shown behind tree 16 . FIG. 5B is a close-up of tree 16 showing the door 78 partially open to reveal a room 86 in a hollow portion of tree trunk 80 . Room 86 may be used as a reward for achievement or good behavior, a time-out place for children or simply a place to explore or to be alone.
[0028] FIG. 6 is indicative of one or more classrooms 90 in the village 10 shown in FIG. 1 . One room may be used for preschool children, another room may be a classroom for pre-kindergarten children, and a third room may be designated for kindergarten children. Classroom 90 is a typical room for small children, with a blackboard 92 , a teacher's desk 94 , children's table and chairs 96 , a flag 98 , a play area 100 and a rocking toy 102 .
[0029] Of course many variations of the foregoing arrangement are possible. Multiple kindergarten rooms may be needed for larger numbers of children of that age. In contrast, some age levels may be entirely absent, depending on the focus of each school.
[0030] FIG. 7 is a pictorial view showing a kitchen workshop 110 inside of one of the shop fronts shown previously. A large work counter 112 is provided, surrounded by additional counter space 114 and 115 and a stove 116 located in counter 114 . A sink 118 is disposed in counter 116 . An instructor 111 is shown teaching a child 113 cooking skills. Kitchen 110 serves as a workshop to learn cooking and related skills and to act out any cooking aspects of stories being studied by the children. In particular, the children may be able to wear a costume while acting out specific aspects of stories being studied by the children. If a particular item is used in a story, the children may then use a similar item, while wearing a costume, in the workshop or elsewhere.
[0031] FIG. 8 is a pictorial view showing a tailor shop 120 inside of one of the store fronts. Sewing machines 122 are set up on tables 124 for use by the children. An ironing board and iron 126 are located in the corner. A teacher's desk 128 is situated at the front of the classroom, and other items needed by the teacher and children are shown.
[0032] FIG. 9 is another pictorial view showing a woodworking workshop 130 for children. A saw 132 is arranged for easy access to the children under a teacher's supervision. A woodworking table 134 has a variety of work pieces 136 thereon and a stool 138 nearby.
[0033] FIG. 10 is a depiction of a science workshop 140 for children according to the present application. Work benches 142 and 144 are equipped with a variety of implements 146 and books 148 thereon.
[0034] It should be understood that various other workshops may be provided within the scope of the present invention. For example, a simulated bank may be provided with counters and teller apparatus for use in teaching children about bank accounts and other financial matters. An art workshop may also be provided for children to learn various artistic skills, including tables with benches for the children to paint, draw, color, or engage in other artistic activities. Other workshops may also be provided to study computers, photography and other subjects, as well as to learn various basic skills.
[0035] As previously mentioned, the foregoing workshops are meant to be used in conjunction with classroom studies for the children to enhance their learning experience. In one embodiment, a workshop may be used to carry out an activity depicted in a children's story. For example, in the little red hen story, the hen bakes some bread. At that point in the story, or after the story has been concluded, the children may go into the kitchen or baking workshop, depicted in FIG. 7 , with the teacher or a cooking instructor and participate in baking bread. The bread may also be eaten by the children, to further enhance the experience. Likewise, when reading the story about Pinocchio, the children may go into the woodworking workshop, shown in FIG. 9 , and make a wooden puppet, under proper supervision.
[0036] In another application of the present disclosure, the workshops may be used to build skills that are studied in the classroom. For example, children may be told about simple science concepts in the classroom. Then the children may go with the teacher, or with a science instructor, to the science workshop and conduct a simple experiment, under proper supervision, to enhance the learning experience of the children. Likewise, children may be taught about the basic process involved in having a bank account. They may then go to the bank workshop and actually open an account, as well as participate in making deposits and withdrawals.
[0037] While this disclosure has been described as having a preferred design, the present disclosure can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the disclosure using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this disclosure pertains and which fall within the limits of the appended claims. | A teaching method and apparatus are provided for using a workshop and a classroom to assist in teaching at least one child about a topic. The method comprises reading a writing about the topic with or to the child in the classroom, creating an item in the workshop relating to the topic, and discussing the created item with the child. The classroom and workshop may be located in a simulated village, such as a fairy tale type village. A fantasy-type structure in the simulated village, such as a simulated tree, has an entry to allow access for a child into an area inside the structure. | 6 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a method for preparing novel transcription factors which modify the procedure of transcription of gene information in a messenger RNA and their use.
[0002] The leading cause of death in developed countries other than Japan is ischemic heart disease. Further, in Japan cancer is the leading cause of death. In the United States of America, ischemia heart disease occupied 60 to 70% of the causes of death for a long time but as the result of the enlightenment movement on an extensive scale by the government and medical institutions, the death due to ischemia heart disease was reduced in an about 40% range. Even at present, however, ischemic heart disease is the first cause of death and occupies 70% of causes of death in the Scandinavian countries such as Sweden and Norway to run ahead of others. Further, in developing countries such as China, the top of the causes of death is ischemic heart disease, and regardless of industrialized countries and developing countries, the development of methods of the therapy and prophylaxis of ischemic heart disease as well as malignant tumor, type II diabetes, cerebrovascular diseases, obesity and the like is rightly an urgent need.
[0003] Ischemic heart disease of a representative life style-related disease frequently causes sudden death, and thus is the target of fear for people in highly industrialized countries. Three major risk factors which cause its onset are (1) a hereditary predisposition, (2) an environmental factor such as smoking, lipid metabolic disorder and diet and (3) aging. Of them, the hereditary disposition and the aging are very difficult to control. On the other hand, a large majority of highly industrialized countries continues making an effort to socially reduce environmental risk-factors. For example, smoking is regarded as a bad habit, and tobacco is banished from the environment, and suits against tobacco companies are frequently started.
[0004] As to the therapy/prophylaxis of ischemic heart disease, only the environmental factor is controllable. Then, for the purpose of removing risk-factors from the environment, a number of methods such as (1) diet therapy, (2) excercise therapy and (3) drugs are advocated. As to the diet, people in developed countries come to avoid intake of foods containing a large amount of cholesterol. Beef and eggs are victimized as the representatives of such foods and their consumption tends to be decreased over a long period of time. Excess intake of energy due to overeating induces obesity. It has been clarified that obesity alone cannot become a risk-factor but obesity combined with insulin resistance (type II diabetes), hyperlipidemia or hypertension becomes to be a risk-factor which is called as syndrome X (also known as silent death syndrome, deadly quartet or visceral obesity) (Reaven G. M, Diabetes 37:159-1607, 1988). In the United States of America, in order to avoid obesity, exercise therapy such as jogging and fitness which accelerate the consumption of energy is prevailing.
[0005] Of environmental risks which cause ischemic heart disease, the serum cholesterol concentration shows the highest correlation. The serum cholesterol concentration as a risk-factor is shown by several criteria. In other words, the criterion is whether or not the serum cholesterol or the cholesterol present in serum low density lipoprotein (LDL) is higher than the normal value or whether or not the serum high density lipoprotein (HDL) is lower than the normal value. It is known that in both cases, the onset risk of ischemic heart disease increases depending on the concentration. Accordingly, the drug therapy of reducing hypercholesterolemia with serum cholesterol lowering agents is also adopted as the standard therapy preventing ischemia heart disease. The serum cholesterol lowering agents have had their effect so that they had come to the most successful drug among therapeutic agents. Above all, an inhibitor of hydroxyl-methylglutaryl coenzyme A (HMG-CoA) reductase which reduces hydroxymethylglutaryl coenzyme A to mevalonyl coenzyme A is the most successful drug which is the top sales among the global drug market. The annual turnover of statin has reached 40 billion US Dollars or more.
[0006] On the other hand, the elucidation of the mechanism has advanced how angina pectoris and myocardial infarction are caused. Up to the 1980s, the medical professionals thought that cholesterol accumulated into the arterial intima formed atheroma plaques that constrict/block the intravascular cavity leading to ischemia of myocardium. However, since the 1970s, several clinical studies had been performed based on the hypothesis that it is a thrombus which constricts/blocks the coronary blood flow and prevention of the formation of the thrombus could prevent/treat ischemic heart disease. For example, such clinical trials used aspirin which is an anti-inflammatory agent and has an action of inhibiting plateletaggregation. Since aspirin induces a peptic ulcer during its chronic administration, it is very difficult to set dossier. In a long-term double blind clinical trials, aspirin was effective in some cases and was invalid in another trial, and thus aspirin has failed to obtain constant beneficial effect. After all, it seems likely that aspirin requires much higher doses to prevent arterial inflammation which frequently causes peptic ulcer and the smaller dose is not effective.
[0007] In the 1990s, instead of the concept that atheroma causes coronary ischemia, the hypothesis is presented that intra arterial blood vessel(s) induced by angiogenesi in atheroma rupture by inflammation and resulting blood clot occludes the blood stream. In other words, the hypothesis that inflammation of intra-arterial blood vessel(s) formed to nourish atheroma plaque(s) is causative of coronary heart disease (Ross R.: New England J. Med. 340:115-126, 1999) has been generally accepted. Therefore, the two major risk factors for coronary heart disease are hypercholesterolemia and chronic inflammation in atheroma plaque(s). It has been clarified from the epidemiological study that when the serum total cholesterol/HDL cholesterol level and the serum CRP level, the marker of chronic inflammation are both abnormally, the ratio of risk for myocardia infarction and cerebrovascular accidents are eight times higher than those being normal.
[0008] There is a therapeutic agent for improving the above described four disorders. However, as is clear from the fact that the co-administration of celibastatin-gemfibrozil induced rhabdomyolysis to threat lives, combined use of drugs may cause a danger of bringing about complicated interactions with each other. Thus, the number of drugs to be administered is preferably reduced. However, there is no drug which can treat the above described four disorders with single therapy.
[0009] There have been a number of therapies for the treatment of type II diabetes which does not requires daily insulin injections. It is known that type II diabetic patients frequently associate obesity at the onset, and its onset and obesity show a high correlation. Further, at the early stage of its onset, the obese patients show hyperinsulinemia and the type II diabetes is caused by the insufficiency in insulin action but not by that in its amount. Because the peripheral tissues in type II diabetes become resistant to the action of insulin. The first choice in treatment is diet therapy. Exercising enhances the peripheral sensitivity of insulin and is used together with the diet therapy.
[0010] If the cause of the onset and aggravation of type II diabetes are due to the insulin resistance in the peripheral tissue, the potentiation of the insulin sensitivity improves type II diabetes. In fact, one of the inventors has proved that 4-O-carboxymethylasco-chlorin (AS-6) of one of ascochlorin derivatives improves in the carbohydrate metabolism in hereditary obese diabetic mouse C57BL ksj (db/db), and the improvement is caused by the reduction in the insulin resistance of white adipose tissue (Hosokawa, Ando and Tamura; Diabetes, 34:267-274, 1985). Furthermore, the individual blood sugar levels of an AS-6 administered group and an AS-6 non-administered group and normal siblings and the carbohyrate metabolic capacity in the white adipose tissue are inversely correlated with a high correlation coefficient (r=−0.899), that is, the insulin resistance of the db/db mouse is caused by the disorder of energy metabolism of white adipose tissue and the improvement of energy metabolism of white adipose tissue by AS-6 reduces its insulin resistance. At present, it is clarified that when triglyceride is highly accumulated in the white adipose tissue, insulin resistance factors such as tumor necrosis factor-α and interleukin-1β which white adipocytes produce (Hotamisligil G. S., Sargaill N. S., Spiegelman B. M. et al: Science 259, 87-91, 1993) trigger the onset of type II diabetes. That is, it has been clarified that the white adipose tissue as well as the pancreatic Langerhans islet β cell is the target for the therapy of type II diabetes. Early in the mid-1980, however, the white adipose tissue was thought a mere store for triglyceridet and it was not anticipated that white adipose tissue plays a central role for a carbohydrate metabolism.
[0011] On the other hand, when attention is paid to cancer, it is clear that “surgical operation”, “anticancer agent” and “radiotherapy” called as the three major therapies are not always satisfactory under the present situation. Above all, anticancer agents which lead to complete cure are rare in spite of the long history of anticancer chemotherapy. The representative cancers which anticancer agents can lead to complete cure are acute myelocytic leukemia, malignant lymphoma, childhood viral tumor and the like. The beneficial effect of anticancer agents cannot be expected for prostatic cancer, breast cancer, large bowel cancer, gastric cancer, hepatoma, pancreas cancer, brain tumor and the like which account for a large majority of cancers. Furthermore, most anticancer agents are highly cytotoxic and the cells which propagate vividly are more sensitive to anticancer chemotherapy nonspecifically. Thus, anticancer agents have a side effect of inhibiting the multiplication of epithelial cells of the small intestine and reducing leukocytes to lower immune potency.
[0012] A greater problem for anticancer chemotherapy is that cancer cells readily acquire resistance to anticancer agents. The anticancer chemotherapies used in combination. However, cancer acquires resistance to any combination of anticancer agents in a short period of time and the anticancer effect is normally lost. Although the mechanism for the acquisition of resistance to anticancer agents is being studied, no means to clinically avoid the resistance has been found.
[0013] It is known that the ascochlorin and its derivatives have a time-dependent efficacy. The condition of exhibiting the drug efficacy is that the blood concentration continues over the threshold but not toxic concentrations for a definite period of time. For example, when AS-6 is orally administered to an animal, its blood concentration rapidly rises over the effective concentration approaching up to the toxic concentrations. Along with this defect, AS-6 is quickly excreted, the short duration of threshold concentration and the oxidation of aldehyde group to a carboxylic acid are weak points of this derivative. The carboxylic acid of AS-6 is less effective in efficacy as compared to AS-6. Further, there is a defect such that since the blood concentration of AS-6 quickly rises up to a concentration of exhibiting toxicity, the toxicity to the liver is easily exhibited.
[0014] 4-O-Methylascochlorin (MAC) of another ascochlorin derivative developed prior to AS-6 has a solubility in water less than 0.7 μg/ml and is extremely sparingly soluble in water, and additionally very poor bioavailability due to the low water solubility has been a disadvantage in exhibiting the drug efficacy. Thus, the orally administered MAC mostly passes right through the gastrointestinal tract and is excreted in feces. Since the duration of the effective blood concentration is short and the peak of the blood concentration is low in animals, the defect of MAC is that the efficacy, for example, the lowering rates of the serum total cholesterol, blood sugar are low.
[0015] In other words, in order for ascochlorin and its derivatives to exhibit their efficacy, the prerequisites are less toxicity and higher drug-efficacy than hitherto ascochlorin derivatives; that is the derivatives continue the blood concentrations over threshold and below toxic levels for a definite period of time.
[0016] It is the most important to investigate and develop therapeutic agents for improving the syndrome X is the search for single compound efficacious for hypercholesterolemia, hypertension, hyperglycemia. Furthermore, it is also one of the problems to develop anticancer agents which do not reduce immune potency and do not allow cancer cells to acquire resistance. 4-O-Methylascocholrin and 4-O-carboxymethylascochorin for which the present inventors obtained a patent are the derivatives by modifying the phenolic hydroxyl group at the 4-position of the orcylaldehyde in ascochlorin. More than twenty years have passed since acquisition of the patents for these derivatives. Further, a number of the derivatives obtained by modifying the hydroxyl group at the 4-position of the orcylaldehyde in ascochlorin with an alky group or an allyl group have been synthesized, and thus it would be difficult to synthesize novel derivatives merely by substituting the hydroxyl group at the 4-position of the aromatic ring which could be patented.
[0017] The ascochlorin series compounds have a property of exhibiting time-dependent efficacy. That is, the blood concentration of an active substance has to be lower than the concentration of exhibiting toxicity and, at the same time, has to continue for a definite period of time above the threshold of exhibiting the drug efficacy. On the other hand, 4-O-alkylascochlorins obtained by alkylating the hydroxyl group at the 4-postion of ascochlorin which have been studied heretofore are hardly soluble in water due to their high fat-solubility. Additionally, the rate of dissolution of the molecule in water from the crystal lattice is extremely slow, and when the 4-O-alkylascochlorins are orally administered to a small animal such as a rat and a mouse at fasting stage, they mostly pass right through the gastrointestinal tract and are excreted in feces. In addition to the low bioavailability, their absorption from the gastrointestinal tract also varies depending on the presence or absence of food intake (Agr. Bio. Chem., 46: 775-781, 1982) because bile secreted by food intake stimulates the rate of their solubility in water. Poor reproducibility in animal experiments has been an obstacle to practical applications of the 4-Oalkylascochlorins.
[0018] The rate of dissolution of the molecule in water from the crystal lattice can be expedited by introducing a polar group in the molecule. In fact, 4-O-carboxymethylascocholorin obtained by substituting the hydrogen at the 4-position of ascochlorin is soluble in water at a concentration of 6% or more at a pH of 7.2 to 7.7 in the small intestine, and thus is quickly absorbed on oral administration. As a result, there has been a defect of exceeding the blood concentration of exhibiting toxicity in a human and an animal.
SUMMARY OF THE INVENTION
[0019] In order to develop therapeutic drugs for common diseases, the syndrome X and cancer by using ascochlorin and its analogs as the mother compounds, the following conditions are have to be met. That is, novel derivatives should have the conditions that (1) they are synthesized at a low cost; (2) they are slowly and surely absorbed from the gastrointestinal tract; (3) they exhibit a serum cholesterol lowering action in animal experiments and a surely improving action to hereditary obese diabetic animal models, hypertensive animal models and the like; (4) they are effective in tumor bearing animal models; (5) they are transcription factors; (6) they have an anti-inflammatory action capable of treating/preventing vascular chronic inflammation and the like.
[0020] With these objects in view the present inventors have focused on the acetal derivative of the aldehyde group on the aromatic ring in ascochlorin series compounds and their derivatives and have tried to synthesize them. Surprisingly, the acetals have never been formed in the normal alcohol exchange reaction by an acid catalyst. However, it has been found that only when the phenolic hydroxyl group adjacent to the aldehyde group on the aromatic ring has been acylated, the acetalization of the aldehyde group occurs in the presence of a basic catalyst under novel conditions. With respect to ascochlorin and its analogs, acetal derivatives have not been reported, and the synthesized acetal derivatives are all novel compounds.
[0021] The novel acetal compounds of ascochlorin derivatives have physico-chemical properties as bulk drugs between MAC and AS-6. Accordingly, on oral administration, the acetal compounds are not so poorly absorbed as MAC but they are not so quickly absorbed as AS-6. Further, as the result of animal experiments and molecular biological study, the novel acetal compounds are inactive prodrugs. However, it has been clarified that they regenerate the aldehyde group in a living body to form a Schiff base with a serum protein, and when the Schiff base reaches a target organ or a target tissue, it becomes incorporated into a cell, and when incorporated into the cell, the serum albumin is digested and the ascochlorin or its derivatives having an aldehyde group is regenerated to exhibit the drug efficacy as a transcription factor. The drug efficacy is referred to exhibit a serum cholesterol lowering action, a metabolism improving action in a hereditary obese diabetic animal model, an antihypertensive action in a hypertensive animal model and an action of inhibiting fat accumulation in a healthy animal. Furthermore, it has been clear that the compounds of the present invention exhibit a prophylactic/therapeutic effect on arterial chronic inflammation, an improving effect on the onset of myxedema due to an insufficient thyroid hormone action, an anticancer action, a prophylaxis/therapy for the restenosis of an arterial cavity expanded by a balloon catheter or a stent and the reception of own grafted cells from stem cells externally differentiated and induced in regenerative medicine and the like, and thus the present invention has been completed.
[0022] The novel transcription factors of the present invention possess pharmacological properties indispensable to the therapy of life style-related diseases such as ischemic heart disease, type II diabetes, hypertension (cerebrovascular accidents), obesity and cancer.
[0023] The novel transcription factors of the present invention are expected to show a therapeutic effect on hypercholesterolemia, hyperglycemia, hypertension and obesity.
DETAILED DESCRIPTION OF THE INVENTION
[0024] The compounds of the present invention can be administered in any administration route accepted for the drugs provided in similar applications in the form of a pure product or a formulation of an appropriate pharmaceutical composition. Thus, their administration can be, for example, orally, nasally, parenterally or topically performed in the form of administration of a solid, a semisolid, a freeze-dried powder or a liquid such as a tablet, a pill, a capsule, a powder, a liquid and a solution, a suspension, an emulsion, a cream, a lotion, an aerosol, an ointment and a gel, preferably at an appropriate unit dose for administering an accurate volume at one time. This composition is composed of a single substance for normal pharmaceutical preparations or a filler and the compounds of the present invention, and may further contain other pharmaceuticals, a carrier, an absorption auxiliary and the like. A pharmaceutically acceptable composition generally comprises about 1 to 99% (by weight) of the compounds of the present invention and about 99 to 1% of appropriate drug additives depending on the type of the agent administered. This composition comprises about 5 to 75% of the compounds of the present invention as medical drugs and the rest of appropriate drug fillers. The effective dose per day of the compounds of the present invention for improving the state of a disease is 0.01 to 100 mg, preferably 0.1 to 10 mg per body weight-kg of an adult.
[0025] A preferred form of administration for diseases as explained in detail above is formulated in a manner such that the dose adjustably set according to the extent of the diseases can be selected. The most important thing in manufacturing pharmaceutical preparations is the restriction derived from the fact that the compounds of the present invention are fat-soluble. The ligand of the nuclear receptor super family is a fat-soluble hormone or a vitamin, and accordingly the compounds of the present invention are naturally fat-soluble. The additives pharmaceutically acceptable for oral administration are prepared by adding normally usable any filler such as mannitol, milk sugar, starch, magnesium stearate, saccharin sodium, talc, cellulose, glucose, gelatin, sucrose and magnesium carbonate. Such a composition takes the form of a liquid and a solution, a tablet, a pill, a capsule, a powder, a sustained release pharmaceutical preparation and the like.
[0026] The composition is preferably in the form of a tablet or a pill, and this composition comprises the compounds of the present invention and a filler such as milk sugar, sucrose and monobasic calcium phosphate, a disintegrator such as starch and its derivative, a lubricant such as magnesium stearate, a binder such as starch, acacia, polyvinylpyrrolidone, gelatin, cellulose and a derivative thereof, and furthermore a surface active agent having an action of wetting the particle surface of the compound of the present invention which is highly fat-soluble and water-repellent with water, a fat-soluble additive, bile acid, phospholipid and the like. It is particularly preferred that the composition comprises an aliphatic synthetic surface active agent or an organic solvent-soluble polymer auxiliary. Examples of these substances include, for example, acacia, sodium alginate, methylcellulose, carboxymethylcellulose, hydroxypropyl cellulose, polyvinylpyrrolidone, bentonite, sodium lauryl sulfate, polysorbate 80, a sorbitan fatty acid monoester and polyoxy 40 stearate.
[0027] The examples of the present invention will now be given below but it goes without saying that the present invention is not restricted by these examples.
EXAMPLE 1
Method for Synthesizing Diacyl Derivatives of Ascochlorin, Cilindochlorin, Ascofuranone, Chloronectin, LLZ-1272-a and LLZ-1272-d
[0028] Ascochlorin and its analogs of 4-O-alkylascochlorins, 4-O-carboxyalkylascochlorins, ascofuranone, cylindrochlorin, chloronectin, LLZ-1272-a and LLZ-1272-d and the like were added to a pyridine/acetic anhydride mixture solution and left to stand at room temperature overnight. The amount of the acetic anhydride added in the pyridine/acetic anhydride mixture solution for acylating ascochlorin and its analogs was in slight excess per one hydroxyl group of the former on a molar basis. After left to stand overnight, the reaction solution was poured into water and about three parts in volume, based on one part in volume of the mixture solution, of ethyl acetate were added to the mixture solution, and the resulting mixture solution was vigorously agitated in a separatory funnel, and the upper layer of the ethyl acetate phase was dispensed. The lower layer was again extracted with ethyl acetate, and the ethyl acetate phases were combined. These combined ethyl acetate phases were washed with 1 N diluted hydrochloric acid and a saturated sodium hydrogen carbonate solution in the order named, and anhydrous sodium sulfate was added to the washed solution to dry it. The anhydrous sodium sulfate was removed by filtration and the filtrate was concentrated under reduced pressure to dryness to obtain a crude acylated product. The acylated product obtained by the present operation was nearly quantitative in yield and had very high purity, and thus could be used in the successive step without further purification.
EXAMPLE 2
Another Method for Preparing 2,4-Di-O-acetylascochlorin
[0029] Another method using acetyl chloride instead of acetic anhydride is as follows. Ascochlorin (0.300 g, 0.741 mmol) was dissolved in anhydrous pyridine (1.3 ml), and acetyl chloride (0.158 ml, 2.22 mmol) was added dropwise thereto while cooling in a water bath. The reaction solution was agitated at room temperature for four hours, and then a saturated NaHCO 3 aqueous solution (2 ml) was added thereto, and the resulting mixture solution was further agitated for 20 minutes. The reaction solution was diluted with water, and then extracted with ether, and the ether layer was washed with a saturated CuSO 4 aqueous solution, water and a saturated sodium chloride aqueous solution in the order named, and then dried with anhydrous sodium sulfate. After filtering the desiccant, the filtrate was concentrated under reduced pressure to obtain 0.320 g (88%) of 2,4-di-O-acetylasco-chlorin (as a colorless gum).
[0030] NMR (CDCl 3 ), 500 MHz): 0.17 (3H, s), 0.81 (3H, d, J=6.7 Hz), 0.84 (3H, d, J=6.7 Hz), 1.63 (1H, qd, J=13.0, 5.5 Hz), 1.86 (3H, s), 1.90-1.97 (2H, m), 2.34 (3H, s), 2.35 (3H, s), 2.36-2.43 (3H, m), 3.35 (2H, d, J=7.0 Hz), 5.25 (1H, t, J=7.0 Hz), 5.41 (1H, d, J=16.0 Hz), 5.87 (1H, d, J=16.0 Hz), 10.27 (1H, s)
EXAMPLE 3
[0031] In the past study, in the investigation of the acylation of ascochlorin and its analogs, it had been found that crystalline 4-O-acyl derivatives could be obtained. Even if 2,4-di-O-acetyl derivatives have been formed in the reaction solution, the acyl group at the 2-position was easily hydrolyzed to return to a hydroxyl group in the purification process. Accordingly, the 2,4-di-O-acyl derivatives which could not be obtained in a crystalline form have hardly been used as starting materials for novel derivatives. In this Example, in order to confirm the formation of the 2,4-di-O-acetyl derivatives, 2,4-di-O-acetylascochlorin (0.1 mmol) was dissolved in a solvent/catalyst of a methanol/triethyl-amine mixture solution for allowing the aldehyde group to react with a primary amine to effect aminocarbonylation, and left to stand at room temperature overnight to try to obtain 4-O-methylascochlorin by partial decomposition of the acyl groups. Surprisingly, the formed product was not 4-O-acetyl derivative but 4-O-acetylascochlorin dimethyl-acetal in which two molecules of methanol were added to the aldehyde group was quantitatively (0.095 mmol) formed. In order to confirm the acetal formation, when 2,4-di-O-acetylascochlorin (0.1 mmol) was dissolved in a triethyl-amine/ethanol mixture solution and treated in the same manner as in the case of using the methanol/triethylamine mixture solution, it was confirmed that 4-O-acetylasco-chlorin diethylacetal was quantitatively (0.098 mmol) formed. Further, when 4-O-acetylascochlorin dimethyl-acetal was dissolved in a diluted hydrochloric acid/methanol solution and hydrolyzed, 4-O-acetylascochorin was formed. Thus, it was confirmed that the compounds which ascochlorin and its analogs having hydroxyl groups at the 2- and 4-positions of the aromatic ring react with excess acetic anhydride in a pyridine solvent to form are the 2,4-diacetyl derivatives, and the acetal derivatives are formed under mild conditions. Naturally, when the aldehyde group was protected with an acetal and allowed to react with a primary amine in the presence of a basic catalyst, no Schiff base was formed.
Preparation of Intermediates Name Structural Formula Yield Purity Note 2,4-O-Di- acetyl- ascochlorin 97% ⊚ Solid, TLC, NMR: Good purity, Used without purification 4-O-Acetyl- ascochlorin 87% ⊚ Crystalline, TLC, NMR: Good purity, Used without purification, Two prepara- tion methods —% ⊚ Crystalline, Yield: not measured, TLC, NMR: Good purity, Used without purification 2-O-Acetyl- 4-O-methyl- ascochlorin Almost Quanti- tative ⊚ Oily, TLC, NMR: Good purity, Used without purification 2,4-O-Di- acetylasco- furanone Almost Quanti- tative ⊚ Oily, TLC, NMR: Good purity, Used without purification
EXAMPLE 4
[0032] On the other hand, the 4-O-monoacetyl derivatives does not form the acetals under the conditions for forming the acetals with the use of the 2,4-di-O-acetyl derivatives as the starting substances (that is, dissolving the 4-O-monoacetyl derivatives in a triamine/methanol mixture solvent and leaving the mixture to stand). However, when the 2-O-acetyl derivatives obtained by acetylating 4-O-methylascochlorin and 4-O-carboxymethylascochlorin with acetic anhydride in a pyridine solvent are dissolved in a triethylamine/alcohol solvent and the resulting mixture solution is left to stand at room temperature overnight, the acetals are formed. Thus, in order to form an acetal, it is necessary that the hydroxyl group adjacent to the aldehyde group has been acylated. When ascochlorin and its analogs whose hydroxyl group at the 2-postion had been acylated were condensed with an alcohol by using a basic catalyst in the presence or absence of a reaction solvent, the acetal derivatives were quantitatively formed as shown in Tables 1 to 3.
TABLE 1 Acetal Formation of Acetylascochlorins Name Structural Formula Yield Purity Note 4-O-Acetyl- ascochlorin dimethylacetal 81% ⊚ Compound 1 4-O-Acetyl- ascochlorin diethylacetal Almost Quanti- tative ⊚ Compound 2 4-O-Methyl- ascochlorin diethylacetal 71% ⊚ Compound 3 Crystal- line 4-O-Acetyl- ascofuranone diethylacetal 50% ⊚ Compound 4 4-O-Methyl- ascochlorin dibutylacetal 51% ⊚ Compound 5 4-O-Methyl- ascochlorin propylene glycolacetal 61% ⊚ Compound 6
[0033]
TABLE 2
Infrared Absorption Spectral Data of Ascochlorins
Acetal
Absorption Maximum (cm −1 )
4-O-Acetylascochlorin
3290, 2972, 1778, 1711, 1415, 1371,
dimethylacetal
1231, 1200, 1108, 1055, 968
4-O-Acetylascochlorin
3264, 2975, 1778, 1712, 1414, 1371,
diethylacetal
1327, 1231, 1200, 1101, 1048, 1003
4-O-Methylascochlorin
3289, 2977, 2933, 1703, 1608, 1575,
Diethylacetal
1449, 1408, 1388, 1373, 1326, 1108,
1069, 1053, 979
4-O-Acetylascofuranone
2978, 1752, 1638, 1373, 1196, 1050,
diethylacetal
998, 752, 664
4-O-Methylascochlorin
3303, 2959, 2872, 1712, 1605, 1571,
dibutylacetal
1454, 1405, 1328, 1227, 1107, 970
4-O-Methylascochlorin
3315, 2972, 2870, 1710, 1573, 1456,
propyleneglycolacetal
1396, 1331, 1238, 1110, 987
[0034]
TABLE 3
NMR Data of Ascochorin Acetals (Chemical Shift: ppm)
Compound No.
2-OH
—CH(OMe) 2
—CH(OCH 3 ) 2
—OCOCH 3
1
9.21
5.65
3.41
2.32
Compound No.
2-OH
—CH(OEt) 2
—CH(OCH 2 CH 3 ) 2
—OCOCH 3
—CH(OCH 2 CH 3 ) 2
2
9.44
5.76
3.54
2.31
1.24
3
9.32
5.76
3.65
1.24
4
9.40
5.76
3.64
2.31
1.24
Compound No.
2-OH
—CH(OBu) 2
—CH(OCH 2 —Pr) 2
—CH(OC 3 H 6 —CH 3 ) 2
5
9.31
5.74
3.57
0.89
Compound No.
2-OH
—CH(—OC 3 H 6 O)—
—CH(—OCH 2 CH 2 CH 2 O)—
6
8.82
5.81
4.30, 3.98
EXAMPLE 5
[0035] In general, acetal formation reaction uses an alcohol exchange reaction in the presence of an acid catalyst. Since direct acetal formation with an alcohol by a base catalyst which is a reaction not existed before is considered, the reaction mechanism in the case of the 4-O-carboxymethylascochlorin 2-O-acetyl derivative was presumed.
Mechanism of Acetal Formation
[0036]
[0037] That is, it has been presumed that after addition of methanol to the aldeyde group, together with nucleophilic reaction to the adjacent acetyl group of a mixed acid anhydride and successive transition of the acetyl group and elimination of the acetoxy group, the second addition of methanol occurs to form an acetal.
EXAMPLE 6
Mouse Serum Cholesterol Lowering Action
[0038] Thirty 5-week-old ICR male mice were bred by allowing mouse standard feed and water ad libitum. The mice were randomly classified into three groups, and one group was taken as a control group to which no drug was administered, and feed containing 0.1% of 4-O-methylasco-chlorin diethylacetal (MAC-DEA) and feed containing 0.05% of MAC-DEA were given to the other two groups, respectively. The body weight, the intake of feed and the amount of drinking water were measured every other day. One week after giving feed, blood was collected and the total cholesterol in serum and the neutral fat were determined.
TABLE 4 Mouse Serum Cholesterol Lowering Action Increase in Body Total Cholesterol Rate of Weight (g/mouse) in Serum (mg/dl) Change (%) Control 6.7 118 Group MAC-DEA 0.05% 7.1 97 −17.8 Group MAC-DEA 0.1% 6.9 90 −23.7 Group Average value of 10 mice in each group
EXAMPLE 7
[0039] Eighteen 7-week-old male db/db mice were bred for one week by allowing mouse standard feed and water ad libitum. The mice were randomly classified into three groups of six mice and each group was housed in a urine collection rat cage and the intake of feed, the amount of drinking water, the amount of urine and the amount of urine sugar excreted were determined everyday. Feed CE-2 was given to the first group as a control group, and feed CE-2 mixed with 0.05% of 4-O-methylascochlorin diethylacetal (MAC-DEA) and feed CE-2 mixed with 0.1% of MAC-DEA were given to the second group and the third group, respectively. The mice were allowed feed and drinking water ad libitum and on the 7th day, blood was collected and the blood sugar, the serum neutral fat and the serum insulin were determined.
TABLE 5 Action of MAC-DEA on db/db Mouse MAC-DEA Control 0.05% MAC-DEA Group Group 0.1% Group Increase in Weight 5.1 5.0 4.8 (g/mouse) Intake of Feed (g/mouse) 6.9 6.9 6.4 Amount of Drinking Water 7.7 5.4 3.2 (ml/mouse) Amount of Urine 4.1 2.5 1.7 (ml/mouse) Amount of Urine Sugar 672 47 10 Excreted (mg/dl) Blood Sugar (mg/dl) 416 273 239 Serum Neutral Fat (mg/dl) 517 259 248 Serum Insulin (·U/ml) 213 175 132
EXAMPLE 8
[0040] Under the Nembutal anesthesia the right kidneys of 24 Wister-Imamichi male rats each having an average weight of about 250 g were removed and the wound was sutured, and the rats were fed for two weeks by allowing diet and drinking water ad libitum. Eighteen rats in good health whose wound had completely healed were selected and used for the experiment. The rats were randomly allocated into three groups of six rats, and 10 mg/kg of the acetal (AC-PG) obtained by bonding propylene glycol to the aldehyde group of 4-O-acetylascochlorin was orally administered to the first group, 5 mg/kg of AC-PG was orally administered to the second group and a AC-PG suspended in 0.2% Tween aqueous solution as a vehicle. The vehicle alone was orally administered to the third group as a control group. On starting the experiment, the rats were allowed feed CE-2 and a 1% sodium chloride aqueous solution ad libitum and 5 mg/kg of deoxycorticosterone acetate was subcutaneously administered once a week. The consumption of the 1% sodium chloride aqueous solution and the amount of urine were determined everyday, and the blood pressure and the body weight were measured once a week. The Table shows the increase in body weight, the average amount of drinking water per day, the blood pressure and the total cholesterol in serum 42 days after starting the experiment.
TABLE 6 Influence of AC-PG on Hypertension Rat Model Control Group AC-PG 5 mg/kg AC-PG 10 mg/kg Increase in Body 45 62 98 Weight (g/rat) Amount of Drinking 86 41 25 Water (ml/rat) Blood Pressure 189 142 131 (mmHg) Serum Cholesterol 217 162 116 (mg/dl)
EXAMPLE 9
[0041] Under the Nembutal anesthesia the right kidneys of 40 Wister-Imamichi male rats each having an average body weight of about 250 g were removed and the rats were fed for two weeks by allowing feed and drinking water ad libitum. Thirty-six rats in good health whose wound had completely healed were selected and used for the experiment. On starting the experiment, the rats were allowed diet CE-2 and a 1% sodium chloride aqeuous solution ad libitum and subcutaneously injected with 5 mg/kg of deoxycorticosterone acetate once a week. The rats were randomly allocated into three groups of six rats, and 10 mg/kg of the acetal (AC-PG) obtained by bonding propylene glycol to the aldehyde group of 4-O-acetylascochlorin was orally administered to the first group, 5 mg/kg of AC-PG was orally administered to the second group and the vehicle a 0.2% Tween-80 aqueous solution alone was orally administered to the third to sixth groups. On the 42nd day after starting of the experiment, the administration of deoxycorticosterone acetate to fourth to sixth groups was stopped and simultaneously the drinking water was changed from the 1% sodium chloride aqueous solution to tap water. Simultaneously, oral administration of 5 mg/kg of AG-PG to the fourth group and oral administration of 10 mg/kg of AG-PG to the fifth group were started and the experiment was completed after 56 days. To the third and sixth groups, a 0.2% Tween-80-containing aqueous solution was administered over the entire experimental period. The blood pressure and the body weight were determined once a week. On the 56th day, the mesenteric arteries were removed and subjected to fat dyeing and the aneurysms dyed in orange were counted. The Table shows the number of aneurysms per mesenteric artery.
TABLE 7 Blood Pressure and Number of Aneurysms per Mesenteric Artery of Prophylactic Group and Therapeutic Group Blood Pressure Number of (mmHg) Aneurysms Therapeutic AC-PG 5 mg/Kg 133 15 (−55%) Group AC-PG 10 mg/Kg 138 2 (−94%) Control 159 33 Prophylactic AC-PG 5 mg/Kg 165 32 (−60%) Group AC-PG 10 mg/Kg 134 27 (−65%) Control 195 78
EXAMPLE 10
[0042] Under the diethyl ether anesthesia the carotid arteries of 18 Wister-Imamichi male rats each having an average body weight of about 250 g were exfoliated to prepare artery exfoliated rats which were models of restenosis (Fraser-Smith E B: J. Pharmcol. Exp. Ther., 275(3): 1204-8, 1995 December:). The rats were randomly classified into three groups of six rats and for two weeks, 50 mg/kg of the acetal (AS-6-DM) obtained by bonding methanol to the aldehyde group of 4-O-carboxymethylasco-chlorin was orally administered to the first group, 25 mg/kg of AS-6-DM were orally administered to the second group and a 0.2% Tween-80 aqueous solution alone was orally administered to the third group as a control. After two weeks, the carotid arteries were removed, fixed with formalin and subjected to HE staining and the thickness of the part most advanced in arterial fat-thickening was measured under a microscope and the inhibition of fat-thickening was compared by taking the thickness in the control group (the thickness of the fat-thickened carotid artery in the exfoliated portion minus the thickness of the artery in normal health) as 100%.
TABLE 8 Influence of AS-6-DM on Arterial Fat-Thickening Inhibition Ratio (%) AS-6-DM 50 mg/kg 81 AS-6-DM 25 mg/kg 56
EXAMPLE 11
[0043] Thirty 5-week-old ICR male mice were randomly classified into six groups and all mice were fed for one week by allowing mouse standard diet CE-2 (a product of Japan CLEA Co., Ltd.). Then, the mice in the first to third groups were intravenously injected with 50 mg/kg of streptozotocin and after one week, blood was collected from the orbit and the blood sugar and the serum insulin were determined to confirm the onset of insulin-dependent diabetes. Ten days after the streptozotocin injection, pancreatic Langerhans islets were removed from the age-matched normal mice in the fourth to sixth groups and 20 pancreatic Langerhans islets were subcutaneously transplanted in the back of each of the diabetic mice. Immediately after transplantation, diet CE-2 containing 0.1% of MAC-DE was given to the first group, diet CE-2 containing 0.05% of MAC-DE was given to the second group and CE-2 was given to the third group. The diabetic mice were further fed for 60 days, and blood was collected from the orbit and the blood sugar and the serum insulin were determined every 15 days.
TABLE 9 Blood Sugar and Insulin of Syngeneic Langerhans Islet Transplanted Mouse Day 0 Day 15 Day 30 Day 45 Day 60 Control Blood Sugar 534 270 390 564 551 Group Insulin <2 2 2 <2 <2 MAC-DE Blood Sugar 566 143 148 125 118 0.05% Insulin <2 5 5 6 6 MAC-DE Blood Sugar 583 121 118 119 131 0.1% Insulin <2 5 6 6 6 Blood Sugar: mg/dl, Insulin: ·U/ml
EXAMPLE 12
[0044] Thirty 5-week-old ICR male mice were randomly classified into three group of ten mice, and mouse standard diet CE-2 (a product of Japan CLEA Co., Ltd.) was given to the first group, and diet CE-2 containing 0.1% of 4-O-methylascochlorin diethylacetal (MAC-DE) was given to the second group and diet CE-2 containing 0.05% of MAC-DE was given to the third group and the mice were continued to be fed. The final body weight and the increase in body weight showed an inhibitory trend in the two MAC-DE groups compared to the control group but statistically there was no significant difference. After 13 weeks, the liver and the epididymal adipose tissue were removed from the mice and lipid was extracted by the Folch method and the triglyceride content was determined. As a result, the triglyceride content in the 0.05% MAC-DE group was reduced 27%, and the triglyceride content in the 0.1% MAC-DE group was reduced 35%. From this fact it would be understood that MAC-DE inhibits fat accumulation.
EXAMPLE 13
Enhancement of Thyroid Hormone Activity in Trans-activation Assay
[0045] The compounds of the present invention do not exhibit the thyroid hormone activity in the transactivation gene reporter assay for thyroid hormone. However, their mixing with a small amount of thyroid hormone enhanced the expression of a reporter gene. That is, when the reporter gene plasmid whose expression is controlled by a thyroid hormone response element and the thyroid hormone expression plasmid were introduced in COS-1 cells and thereafter the introduced cells were treated with thyroid hormone and the compounds of the present invention, the amount of expression of the reporter gene increased. This result shows that the compounds of the present invention are not agonists for the thyroid hormone nuclear receptor and enhance the gene expression through a cofactor in the process of transcription of the thyroid hormone activity.
EXAMPLE 14
[0046] Thirty 5-week-old ddY male mice were randomly classified into three groups of ten mice and fed for 13 weeks by allowing feed and water ad libidum. Meanwhile, the mouse standard diet CE-2 (a product of Japan CLEA Co., Ltd.) was given to the first group, and diet CE-2 containing 0.1% of 4-O-methylascochlorin diethylacetal (MAC-DE) was given to the second group of mice and diet CE-2 containing 0.05% of MAC-DE was given to the third group. The final body weight and the increase in body weight showed an inhibitory trend in two MAC-DE groups compared to the control group but statistically there was no significant difference. After 13 weeks, the livers and the epididymal adipose tissues were removed from the mice and lipid was extracted by the Folch method and the triglyceride content was determined. As a result, the triglyceride content in the 0.05% MAC-DE group was reduced 27%, and the neutral fat content in the 0.1% MAC-DE group was reduced 35%. From this fact it would be understood that MAC-DE inhibits internal fat accumulation.
EXAMPLE 15
[0047] Eighteen five-week-old ICR male mice were subcutaneously inoculated with 10 6 cells of Ehrlich ascites carcinoma intraperitoneally and after 24 hours, and the mice were classified into three groups of six mice, and 4-O-methylascochlorin diethylacetal (MAC-DE) was suspended in 0.2% Tween-80 and 1 mg/kg and 4 mg/kg were orally administered to the first group and the second group twice a day at 9:00 and 20:00, respectively, and a MAC-DE-free Tween-80 aqueous solution was given to the third group as a control group. The administration was continued for successive 7 days and after completion of the administration, the mice were fed for two weeks. On the 21st day, a nodular tumor was removed from the mice and the body weight was determined and the effect of MAC-DE on the inhibition of tumor growth was examined. As would be clear from Table 10, MAC-DE significantly inhibits the growth of Ehrlich carcinoma.
TABLE 10 Effect of MAC-DE on Inhibition of Ehrlich Solid Tumor Increase in Body Weight of Tumor Inhibition Weight (g/mouse) (g/mouse) Ratio (%) MAC-DE 1 mg/kg 10.8 0.25 81 MAC-DE 4 mg/kg 9.2 0.06 96 Control Group 9.6 1.34 —
[0048] The present invention provides novel therapeutic agents for atherosclerosis, hypercholesterolemia, hypertension, insulin-independent diabetes (also called as type II diabetes), chronic inflammation, myxedema, malignant tumor and the like and is additionally useful for the syndrome of multiple risk factors (syndrome X) for which no appropriate therapeutic means has existed, the prevention of the restenosis of an arterial cavity expansion by a stent and a balloon catheter and the security of take of a graft in regenerative medicine. | The present invention has an object to develop novel compounds which are effective for the therapy of syndrome X, cancer, myxedema, vascular chronic inflammation and the like, and furthermore prevent/treat the restenosis caused in an artery expansion by a balloon or a stent and have the activity facilitating regenerative medicine by inhibiting rejection of own cells or tissues to be transplanted and the method for preparing the same. Novel acetal derivatives obtained by acylating the hydroxyl group at the 2-position of the orcylaldehyde which ascochlorin and its analogs have and thereafter bonding an alcohol to the aldehyde group in the presence of a basic catalyst are found to achieve the object. | 2 |
RELATED CASES
This is a Continuation application of Continuation-In-Part application Ser. No. 09/238,104, entitled “Method for Filling Voids with Aggregate Material”, filed Jan. 27, 1999, issued Nov. 27, 2001 as U.S. Pat. No. 6,322,293, which continues from patent application Ser. No. 09/015,374, entitled “Backfilling Underground Voids”, filed Jan. 29, 1998, issued Nov. 27, 2001 as U.S. Pat. No. 6,322,292, which is based on Provisional Patent application Serial No. 60/036,174, entitled “Backfilling Underground Voids”, filed Jan. 29, 1997.
BACKGROUND
(i) Field of the Invention
This invention relates generally to methods for filling voids with particulate or aggregate material such as crushed rock or gravel, and, more particularly, to an improved method for filling below- and above-ground voids using tailings and similar aggregate materials produced in mining and similar operations.
(ii) Related Art
A number of mining, excavation and construction operations require the deposition of large amounts of aggregate material in some form of cavity or void.
For example, mining operations ordinarily involve removal of ore-bearing rock or earth from a geological formation, thus creating one or more voids in the formation. The excavated rock is typically crushed and processed to extract the ore, leaving the crushed rock residue as tailings. If left unconfined above ground, the massive amounts of tailings produced by a typical mining operation present serious space and environmental problems. However, the tailings are commonly returned into the mine to backfill the voids which have been formed in the underground formation, while in other operations they are deposited in an above-ground pit or holding area.
For example, it is common to mine underground by forming a vertical lift shaft or helical tunnel and then to mine horizontally extending tunnels at different levels. Large volumes of ore are then removed via the horizontal tunnels by blasting a succession of stopes or underground voids upwardly from the far end of each tunnel back toward the center axis. In order for safe mining to proceed it is necessary to backfill each underground void or stope formed as part of the blasting and ore evacuation procedure, so as to support the “roof” above the stope and thereby allow an immediately adjoining volume of ore to be blasted without danger of collapse.
The backfilling is typically carried out by mixing a suitable particulate solid material, usually the mine tailings, with cement and water, and then conveying, trucking or pumping the backfill mixture to the location of the void. Excess water draining from the backfill mixture must be pumped from the mine and the backfill mixture allowed to set to form a solid fill in the stope.
The cost of backfilling is significant and can be as much as 20% of the total cost of the mining operation. The cost of backfilling is directly related to the cost of the cement content in the filling mixture but a significant cost is also involved in transport of the material to the void. The most convenient way of transporting the material to the void is by pumping through pipes but this requires a high water content in the backfill mixture. This is particularly the case with many mine tailings, due in part to the high void content which results from the comparatively uniform aggregate size of the crushed rock.
A conflicting requirement is that, in order to avoid mud slides underground (i.e., the fluidic collapse of part of the backfilled material) the recommended percentage of solids in the fill is above 74%. It is often difficult to pump such a mixture (at this ratio of solids) significant distances, but any increase in water content to improve pumpability increases the risk of mud slides and increases the volume and expense of cement required in the mix to in order for this to cure and reach specified strengths, which are typically in the order of 1ÿMPa. The amount of cement varies according to the backfill material and the water content but is usually around 6% in order for the fill to reach the required strength.
In some types of mining operations, the tailings are not used to backfill the mine as described above, but are instead deposited above-ground in a large pit or similar containment area. The process is essentially similar to that described above, except that in the absence of a requirement for structural strength the cement or other binder component may be eliminated. The large amounts of water which are required in order to pump the material continue to present serious problems, however, even in an above-ground placement. For example, dams, retaining walls or similar structures must often be provided to prevent mudslides and spills. Moreover, the water often becomes highly contaminated from contact with the tailings (whether from naturally-occurring minerals or from chemicals used in the ore extraction process), with the result that the use of large volumes of water to place the tailings leads to a serious problem containing and treating the water itself.
It is therefor desirable to be able to provide an aggregate fill material which is easy to pump and therefore economic to place, without requiring the high water content which increases the risk of mud slides or which requires a high cement content, which in turn increases the cost of the operation. Such filling material is desirable for use in a wide variety of mining situations, such as, for example, stope fill, the filling-in of disused mines to remove hazardous threats from cave-ins in subsequent open cast mining operations, and other similar situations. Moreover, such filling material is desirable for use in a wide range of other mining and non-mining operations, both above and below ground.
SUMMARY OF THE INVENTION
The present invention therefore provides a method for filling voids with an aggregate material, in mining or other operations, said method comprising the steps of forming a fluid filling material by mixing particulate solid material with a fluid foam material in an amount sufficient to form a pumpable aerated slurry, flowing the aerated slurry into the void, and allowing the slurry to set therein. The particulate solid material may comprise mine tailings.
The fluid foam material may comprise a mixture of a binder and foam. The binder may be a hydraulic cement. The foam may be formed from water and frothing agents.
Preferably the step of flowing the aerated slurry into the void includes pumping the slurry from the point of mixing to the void.
The step of flowing the aerated slurry into the void may further comprise the step of applying a defoaming agent to the slurry so as to collapse the foam therein when the slurry is in the void. The step of applying the defoaming agent to the aerated slurry may comprise the step of mixing the defoaming agent with the slurry as the slurry is injected into the void.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic, cross-sectional, elevational view showing the backfilling of an exemplary mine stope in accordance with the present invention; and
FIG. 1A is a diagrammatic, cross-sectional, electional view, similar to FIG. 1, showing the filling of an above-ground void in accordance with the present invention; and
FIG. 2 is a perspective, somewhat diagrammatic view of a nozzle assembly for mixing a defoaming agent with the aerated slurry as the slurry is injected into a void.
DETAILED DESCRIPTION
Notwithstanding any other forms that may fall within its scope, one preferred form of the invention will now be described by way of example only with reference to the accompanying drawings, which show a typical mining operation in which the present invention may be used. The voids in the illustrated example are underground, but in other instances the void may be an above-ground containment area.
As used in this description and the appended claims, the term “void” includes all forms of cavities, pits, openings and the like, whether above or below ground, and whether a man-made or natural formation. Moreover, while the example described below is directed to the disposition of tailings which are in essence a “waste product” of the mining operation, it will be understood that the present invention is also applicable to the pumping and placement of aggregates which have been provided for the express purpose of providing fill in a selected area or constructing an engineered structure.
In a typical mining operation in which the present invention may be used, and as can be seen in FIG. 1, a vertical access, which may be for example a lift shaft or a helical tunnel 10 , is mined into the earth 12 from the surface 14 . At the required depth, or at various intervals, horizontal tunnels 16 extend outwardly from the axis shaft 10 to their remote ends 18 . To mine a body of ore an area 20 above the end of the tunnel 18 is drilled and explosives placed and detonated to collapse the ore material within the area 20 so that it falls into the tunnel 16 and can be removed by well known mining techniques.
In order to proceed with the mining operation by next blasting and collapsing the adjacent area 22 , it is first necessary to fill the empty void 24 formed by the collapse and removal of material from the area 20 (the void 24 is commonly referred to as a “stope” in the particular form of mining operation which is shown in FIG. 1 ). This may be conveniently carried out by drilling a small access hole 26 from the surface 14 into the upper portions of the stope 24 , and blocking the tunnel at the point 28 (where it enters the stope) in a suitable manner.
Backfilling material is then prepared according to the present invention by mixing a suitable particulate material (typically, the mine tailings resulting from processing the ore removed from the mine) with an aerated slurry in a mixing apparatus 30 . In many embodiments the slurry will include a predetermined amount of binder, such as portland cement. The aerated slurry is suitably formed by mixing the binder with finished foam, which is typically formed from suitable frothing agents; in those embodiments where no binder is used, the aggregate may be mixed with the finished foam itself.
As is shown schematically in FIG. 1, the apparatus preferably includes components for supplying the binder, such as cement slurry 32 , tailings or other particulate material 34 , and foam 36 , and for feeding these into a mixer 38 .
The binder component may be any suitable material for binding the aggregate following placement, including Portland cements and other hydraulic cements, slag cements, Type-C fly ash cement and other fly ashes, as well as suitable non-hydraulic binders. The tailings or other solid material, in turn, may be crushed if necessary to provide the particulate constituent; due to the presence of the foam component, however, the grading of the aggregate or other particulate will not normally be critical.
The foam component, in turn, may be provided by any suitable foam material or foaming/frothing agent, such as the various aqueous and non-aqueous foam materials and chemical foaming agents which are known to those skilled in the relevant art. Aqueous foam materials, which are generally preferred because of their economy, consistency, and ease of use, are typically formed by mixing a liquid foam concentrate material (suitable examples of foam concentrate material include “Mearl Geocell Foam Liquid”, available from The Mearl Corporation, Roselle Park, N.J., along with similar products available from Elastizell Corporation, Ann Arbor, Mich., and other suppliers) with water to form a foam solution, and then mixing the foam solution with air to form a finished foam having a stable bubble structure (suitable foam generators of this type may be obtained from The Mearl Corporation and from Pacific International Grout Company, Bellingham, Wash.). A suitable apparatus for generating large amounts of foam material for mixing the slurry is also available from Pacific International Grout Company, and is described in U.S. Pat. No. 5,803,596, which is hereby incorporated herein by reference.
In some embodiments it may be desirable to configure the feed mechanisms so as to enable the operator to control the amounts and relative proportions of the constituents as these are being fed into the mixing apparatus; for example, the relative proportions of cement slurry and foam solution may be controlled using variable-speed metering pumps, and the tailing particulate may be fed from a hopper using a controllable speed conveyor or rotary metering valve.
It will be understood, however, that any suitable feed and mixing mechanisms may be used in carrying out the present invention, and the choice of mechanisms will depend to a significant degree on the form in which the fill constituents are supplied. For example, FIG. 1 shows mixer 38 as a horizontal paddle mixer, which may provide certain advantages where the cement is already in slurry form and the foam constituent is added as a finished aqueous foam. In other embodiments, however, the mixing of water and cement dust may be performed in the mixer itself, and the foam component may be supplied as a dry or liquid chemical frothing agent which is combined with water either in or before entering the mixer. Accordingly, a vertical tub mixer or other form of mixer may be preferred in some embodiments.
Similarly, FIG. 1 shows the system as incorporating a large positive-displacement, progressive cavity, screw-type pump, of the type which are available under the trademark Moyno™ from Robbins & Meyers, Dayton Ohio, which has several advantages (including efficiency, precise control of the pumping rate, and avoiding damage to the bubble structure in the aerated fill material), but again it will be understood that any suitable type of pump may be employed in this role.
The resultant fluid filling material contains a large amount of entrained air by virtue of the foam component. As can be seen in FIGS. 1 and 1A, this is flowed from the mixer 38 into the mine void 24 or above ground void 24 a , e.g., by using the pump 40 and pipe 42 .
It has been found that by using an aerated slurry (as opposed to a conventional water-aggregate slurry), the bubble structure in the fill material renders this significantly more fluid and pumpable than a conventional mixture of water and particulate solid material, and therefore relatively easy to pump over long distances using the pump 40 and pipe 42 , even when the percentage of solids in the fill is kept above the minimum required to avoid the risk of mud slides in the stope 24 . Moreover, where cement is used in the mix, the comparatively low water content of the aerated slurry makes it possible to use much less cement as compared with the unfoamed materials; for example, to achieve a comparable strength, approximately 4.5 to 5% cement is now required compared with at least 6% when foam is not used.
The additional expense of the foam, both in the mixing process and in the frothing agents, is more than off-set by the decrease in cement quantities (by reducing the water content), improvements in pumpability, increase in overall volume, and increase in the percentage of solids in the mix.
Although the examples described above note the advantages of the present invention when the fill material contains cement, it will be understood that in some applications the fill material of the present invention may contain little or no cement or other binder. For example, if there is no requirement that the fill have any significant structural strength, the fluid fill material may essentially comprise aggregate (e.g., crushed rock) and finished foam alone. Hence, depending on the application and the specifications for the particular job, the cement or other binder component may be nil or may be sufficiently high to react with the water component and provide the fill with maximum available strength when cured.
The amount of foam required, i.e., the ratio of foam to solids, will vary somewhat depending on the size and coarseness of the particulate (e.g., the crushed tailings), the shape of the particulate, the stability of the foam material which is being used, the distance over which the material is being pumped, and other factors to be determined for the particular job. From a practical standpoint, however, the amount of water which is added to the fill by the foam component will always be far less than the amount of water which would be required to render the particulate pumpable without the foam; for example, in testing applicant has found that the amount of water contained in the foam needed to render crushed tailings pumpable is roughly 1 to 18 as compared to water without foam.
The aerated slurry may be flowed directly into the void and allowed to cure without further treatment, as shown in FIG. 1 . In many applications, however, it is desirable to collapse the bubble structure of the material once it has entered the void and pumpability is no longer required. For example, in the case of a mine backfill operation there is usually a large volume of tailings to be disposed of and only a limited amount of void space within the mine to hold them. Even in above-ground placement, a reduced final volume generally allows for a smaller, more economical containment area.
In order to collapse the bubble structure of the fill material, a suitable “defoaming” agent can be added to the fluid material at the injection point, as it is discharged into the void. For example, FIG. 2 shows a nozzle assembly 50 by which a defoaming agent is added to the fill material immediately before it enters the void.
As can be seen, the nozzle assembly 50 is mounted to the discharge end of conduit 42 so as to receive the flow of the aerated slurry therefrom, as indicated by arrow 52 . The defoaming agent is fed into the nozzle assembly in liquid form, via a secondary conduit 54 , in the direction indicated by arrow 56 . For purposes of efficiency the defoaming agent can be fed to the nozzle assembly at a metered rate which corresponds to the rate of flow of the aerated fill; an example of an apparatus suitable for providing an additive to a discharge nozzle at such a metered rate is described in U.S. Pat. No. 5,803,665, which is hereby incorporated herein by reference.
The defoaming agent is mixed with the fill material by a static mixer 58 which is mounted in the assembly downstream of the secondary conduit 54 , and the mixed material is discharged from this into the void though an output pipe 60 , in the direction indicated by arrow 62 .
The defoaming agent, having been mixed with the fill material, collapses the bubble structure very rapidly once the material has been deposited, without interfering with the pumpability of the fill material upstream of the nozzle assembly. It will be understood, however, that the relationship of the components shown in FIG. 2 is illustrative of one exemplary embodiment only. For example, the static mixer may not be present in all embodiments, and the line for adding the defoaming agent may be attached further up the main conduit 42 so that mixing simply takes place inside the conduit itself. Furthermore, the defoaming agent line may simply discharge into the mass alongside the end of the main conduit, or may applied to the fill material after it has been deposited in the void, using a separate line or vessel.
Although the amount of defoaming agent required will vary depending on the actual composition and operating conditions, in general only a very small amount is needed to completely collapse the bubble structure. While any suitable defoaming agent which effectively collapses the bubble structure may be employed, silicone oils and other silicone-based defoaming agents are generally preferred because of their good initial action, quick knock-down, and effectiveness within wide ranges of pH; one example of a silicone-oil defoaming agent is “ANTIFOAM-A”, available from Dow-Corning. Other suitable defoaming agents, some of which are limited in effectiveness to certain pH ranges, include fatty amid-based products (e.g., “NOPCO 198” available from Diamond Shamrock), fatty acid-based products (e.g., “NOPCO KF”, available from Diamond Shamrock), and fatty ester and hydrocarbon wax-based products (suitable examples of which are also available from Diamond Shamrock).
Because the defoaming agent eliminates the bubble structure upon or shortly after placement of the fill material, the operator can add however much foam is needed to ensure pumpability of the material, without concern about increasing the final volume at the receiving end. The relatively small amount of water which is released when the bubbles collapse can serve to hydrate the cement or other aqueous binder when this is present in the mix. The result is a dense fill in the void having very little greater volume than the volume of tailings or other particulate which was initially incorporated in the fill. Moreover, there is little or no excess water which must be removed, treated, or otherwise dealt with at the placement site.
It is to be recognized that various alterations, modifications, and/or additions may be introduced into the constructions and arrangements of parts described above without departing from the spirit or ambit of the present invention as defined by the appended claims. | A method for filling a void using an aggregate material, such as mine tailings, the fill material being pumped from a site which is located remote from the void. A fluid, aerated material is formed by mixing the particulate solid material with finished foam. The aerated material may also include cement or another binder for applications requiring structural strength. The bubble structure which results from incorporating the foam constituent in the fill material renders this much more fluid and pumpable, thereby allowing the use of much higher solids-to-water ratios than would otherwise be possible while still being able to pump the material over significant distances. This reduces the possibly of fluidic collapse of the material in the void, and produces other advantages as well. | 4 |
REFERENCE TO RELATED APPLICATION
This application is a continuation of U.S. patent application Ser. No. 07/265,565, filed Nov. 1, 1988, now U.S. Pat. No. 4,950,268, issued Aug. 21, 1990, which is a continuation-in-part of U.S. patent application Ser. No. 07/019,755, filed Feb. 27, 1987 by the present inventor and Dan Rink and Garrett Lee, for which priority is claimed.
BACKGROUND OF THE INVENTION
In the field of medicine the use of laser devices for treatment purposes is becoming commonplace. Such devices are used for cauterization of wounds, excision of tissue, selective thermal absorption in tissue, welding of tissue through the formation of scar tissue, and the like. Recent developments in intravascular treatment point to recanalization of atherosclerotically occluded vessels virtually anywhere in the human body, including the relatively small vessels which supply the heart muscle itself. Such developments are described in copending U.S. patent application Ser. No. 07/109,755, filed Feb. 27, 1987 by the present inventor and Dan Rink and Garrett Lee.
Generally speaking, lasers designed for medical use should be highly controllable with respect to the power output level of the laser, and the duration of the laser illumination. Paradoxically, although the laser output power rarely exceeds approximately 20-25 watts for medical treatment purposes, the amount of power used to generate this laser power level is extraordinarily high. In lasing medium which operates continuously, kilowatts of power are consumed, even on a standby basis, so that a few watts of light energy can be delivered briefly or sporadically to the desired application site. The heat generated in the lasing cavity and in the power supply require that an external cooling system be provided. Thus an external source of cold water is generally required, and hundreds of gallons of water are expended in relatively short procedures. External cooling systems add to the complexity and expense of a medical laser, and create further connection and maintenance problems.
In pulsed mode laser devices, there is the opportunity to save power consumption since the lasing medium is operated only sporadically. However, pulsed mediums do not react predictably when first activated, due to thermal and dimensional effects. For example, when a NdYAG laser rod is first pumped by an arc lamp, the rod experiences a rapid thermal buildup which alters the axial dimension of the rod. As the rod changes in shape, the quality of the laser output pulse is severely affected. Thus prior art devices may provide erratic power outputs in pulse or burst modes of operation.
This problem is complicated by the fact that many prior art pulsed laser systems measure the power output of each pulse (by any of several techniques known in the art), compare that power level to a preselected level, and in response alter the intensity or period of succeeding pulses. The inherent time lag of this process, together with the averaging errors and the potential instability in such level-hunting systems, can create unacceptably erratic performance.
Prior art lasers have employed high voltage DC power supplies to pump and fire a pulsed mode laser, and pseudo-continuous operation may be added by charging capacitors with the high-voltage power and sequentially connecting the capacitors to a flash lamp or the like to fire the laser to produce a plurality of time-separated pulses. However, such power supplies are expensive and inefficient, and there is a limit to how many capacitors can be provided in a practical laser apparatus.
Another difficulty found in medical and other forms of work with lasers is that prudent safety considerations that all personnel wear laser safety goggles whenever they are in an area in which a laser is in use. Particularly in medical settings such as a surgical operating room, the surgeons and assisting staff, the anesthesiologists and the patient must be equipped with safety goggles. Often the goggles interfere with other equipment, such as sterile masks, the anesthesia mask, and the like, and are a distraction at best. There is no remedy for this problem known to the present inventors.
SUMMARY OF THE PRESENT INVENTION
The present invention generally comprises a laser driving method and system that provides a laser system with a high safety factor, low power consumption, and a compact, simplified power supply. The laser system includes a pumped rod-type laser and an arc lamp or the like disposed to illuminate the lasing medium, such as a NdYAG crystalline rod. The apparatus includes a full wave rectifier to power the arc lamp, and a MOSFET switching circuit to turn on and off the arc lamp power at controlled times during each half cycle of the power waveform so that the laser medium is pumped and optically discharged once during each half cycle of the power supply.
In order to control the power of the laser pulse, the laser power output is measured by a photodetector during each half cycle, and the photodetector output is integrated and compared with a pre-set, variable laser output power level. When the actual laser power reaches the preset power level, the comparator initiates turning off the MOSFET switching circuit power for that respective half cycle of the power waveform. At the beginning of the next half cycle the integrator is reset and the MOSFET switching circuit is turned on again. Thus the power of each pulse of the laser is measured and chopped at the appropriate instant to deliver the precise power level desired.
The full wave rectified power is used to drive the laser medium in a burst mode of several pulses, or in a repetitive pulsed mode that emulate the effects of continuous output lasers. The full wave rectified power supply also permits the use of 110 VAC utility power, and obviates the need for external cooling of the laser. The apparatus also includes safety circuits that permit laser operation only when the internal cooling system is operating, when the current to the arc lamp is below a maximum level, and when the temperature created by the laser illumination on a target or on a portion of the beam delivery system is above a variable preset level, and the like. A further safety circuit detects the presence of laser radiation in the area surrounding the laser to shut it off when laser light escapes from the system. For medical, industrial, and experimental laser uses, this feature obviates the need for laser safety goggles for operational personnel.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic representation of the laser power control circuit of the present invention, and in particular the circuit that senses and controls the portion of each half cycle of the power waveform that is applied to the laser pumping light source.
FIG. 2 is a schematic representation of a portion of the laser power control circuit of the present invention, and in particular the temperature safety circuit that senses an overtemperature condition in the laser system and shuts off power to the laser power supply.
FIG. 3 is a schematic representation of a portion of the laser power control circuit of the present invention, and in particular the cooling safety circuit that shuts off the laser power supply whenever there occurs an interruption in flow of coolant to the laser cavity.
FIG. 4 is a schematic representation of a portion of the laser power control circuit of the present invention, and in particular the photodetector circuit that senses the laser output during each half cycle of the power waveform, and shuts off the laser whenever a desired, preset output power level is reached.
FIG. 5 is a schematic representation of a portion of the laser power control circuit of the present invention, and in particular the current level sensing safety circuit that detects excessive current flow in the conductor to the laser optical pumping source and shuts off the laser power system.
FIG. 6 is a graphic depiction of the timing sequence of the laser power control circuit of the present invention.
FIG. 7 is a schematic representation of a portion of the laser power control circuit of the present invention, and in particular the FET signal control circuit that delivers power to the laser optical pumping source.
FIG. 8 is a schematic representation of a portion of the laser power control circuit of the present invention, and in particular the laser radiation area detector safety circuit.
FIG. 9 is a schematic representation of the fiber break detector circuit of the present invention.
FIG. 10 is a graphic depiction of the timing sequence of the fiber break detector circuit of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention generally comprises a laser driving and control system and method of operation thereof. The most salient features of the invention is that it provides a laser system which is power efficient, stable, accurately controlled and extremely safe. Although the preferred embodiment is described with respect to medical applications, it may be appreciated that the attributes of the laser system of the present invention could be directed to industrial, investigative, and other uses.
The invention is adapted to be employed with a standard-in-the-art laser generating unit, or head, which comprises a closed reflective chamber housing a lasing rod and an optical pumping source such as a flashlamp in operational relationship. One possible configuration of the laser head includes a optical enclosure having a uniform, elliptical cross-sectional configuration along a longitudinal axis, with focal lines parallel to the longitudinal axis, and the laser rod and flashlamp extending parallel along respective focal lines. The lasing rod material may be NdYAG or the equivalent. A conventional cooling system which circulates coolant in the laser head is provided to remove excess heat generated by absorption of a good portion of the flashlamp energy by the laser head.
A significant aspect of the invention is the design and operation of the power supply that controls the flashlamp and thus the laser output power level. Unlike prior art laser systems, which use high voltage DC power supply arrangements, the present invention is designed to use 117 VAC (or 110 VAC) power directly from the utility power source. With regard to FIG. 1, the power control circuit includes a transformer 11 to step down the input line voltage and deliver it to a full wave rectifier 12. The result is the rectified sinusoidal power wave P, shown in FIG. 6. The power wave P is fed to a Zener diode voltage regulator, which chops the peaks of the power wave P at a desirable voltage to form a low voltage analog of the power voltage signal.
The analog power signal is fed to the trigger input of a timer 16, such as the common 7555 IC timer known in the prior art. The circuit includes a trio of such timer circuits 16, 17, and 18, connected output-to-input in serial fashion. The input 19 of timer 16 is connected between a capacitor 21 leading to ground, and a resistor 22 connected to the 5 VDC power supply which also drives the timer 16. As is known in the prior art, the resistor 22 and capacitor 21 comprise an RC network which slowly charges the input 19 to 5 volts in a time period determined by the values of the resistor and capacitor. Each of the timer circuit 17 and 18 operate in a similar fashion, although the values of the respective resistors and capacitors at the input differ to determine selected time delay factors.
In addition, the power wave analog signal is connected to the input 19. Whenever this signal pulls the input low, to a range of one-third the power supply voltage, the timer output 23 goes high forming the signal C 1 depicted in FIG. 6. Note that signal C 1 switches high as the power waveform P approaches zero, and stays high until P exceeds the threshold voltage once again. The on-off thresholds may be set to be identical so that the signal C 1 is symmetrical about the zero point of the power voltage P, but this in not necessary for the system to operate.
The output of timer 16 is connected to the input of timer 17, which is connected to be triggered immediately by the fall of signal C 1 and to remain on only a short time. The output of timer 17, signal C 2 is fed to timer 18, which is connected to produce the signal C 3 . It is important to note that signal C 3 commences when C 2 goes low, so that C 2 comprises a firing signal for the system. The output of timer 18 is connected to an actuating input of a MOSFET laser power supply control 33, described in the following specification, so that the laser pumping light source is turned on whenever signal C 3 goes high. The operating period (on time) of timer 18 also establishes a maximum elapsed time for operation of the pumping light source during each half cycle of the power voltage waveform.
It should be pointed out that the timer 18 differs from the others in that the reset input 31 is not connected to the 5 VDC power supply for instant reset. Rather, input 31 is connected to the output of reset AND gate 32, which has a plurality of reset inputs 32R. Whenever any of the reset inputs receive a low-going input, the AND gate 32 causes the timer 18 to reset and the output C 3 goes low. Thus the inputs to gate 32 determine that period of each pulse of signal C 3 and the laser pulse itself may be terminated before the maximum elapsed time, as shown by reference numeral RC 3 in FIG. 6. Furthermore, a continued low input to the gate 32 will effectively block operation of the laser. Thus the inputs 32R comprise important control factors for the operation of the laser.
With regard to FIG. 4, another important portion of the invention is an output power monitor circuit 36, which has an output connected to one of the reset inputs 32R. The circuit 36 includes a photosensor 37, preferably a linear response photodiode fabricated of silicon or the equivalent, and placed in the laser light path to receive a small fraction of the laser output beam. For example, the photosensor 37 may be placed behind a partially conducting mirror disposed in the laser beam path, to receive the small percentage of beam power that is passed by the mirror. The photosensor outputs are connected across the inputs of an operational amplifier 38. The output of the op amp 38 is connected to the negative input in a feedback loop by capacitor 39, so that the output current of photosensor 37 is integrated with respect to time and represented by the voltage across the capacitor 39. The integration product is an analog signal having a voltage level which varies generally linearly with the energy output of each laser pulse.
Also connected in parallel with the capacitor 39 is a solid state switch 41. The switch 41 has a trigger input connected to receive the signal C 2 and is actuated thereby to short out the capacitor and remove the accumulated voltage thereon. Thus the firing signal C 2 resets to zero the voltage signal at the op amp 38 output just prior to firing the next laser pulse.
The voltage signal output of op amp 38 is conducted to the negative input of op amp 42. The other input is connected to the wiper connection of a potentiometer 43, which may be controlled manually or by appropriate software. It may be appreciated that whenever the signal from op amp 38 exceeds the voltage set by potentiometer 43, op amp 42 will emit a low-going signal that is connected directly to one of the inputs 32R of the reset AND gate 32. Thus the energy output of each pulse of the laser is monitored in real time, and the power supply is squelched when the pulse energy equals the selected, desirable pulse energy level. This system is extremely accurate in delivering the desired laser energy to the device utilizing the laser radiation, since it eliminates pulse power averaging errors and correctional time delays which are known in prior art systems.
Another control circuit 46 connected to the safety reset switch 82, shown in FIG. 3, is designed to monitor the cooling fluid flow to the laser head, and to deactivate the laser when there is insufficient coolant flow. The circuit 46 includes a bridge-type resistive fluid pressure sensor 47. The sensor 47 is connected by fluid conduits in a parallel relationship to the main coolant supply conduit 48, so that the pressure drop produced by fluid flow resistance in the conduit 48 is presented to the sensor 47. The opposed bridge outputs of the sensor 47 are connected across the inputs of op amp 49. Connected from the output to the negative input of op amp 49 is a parallel resistive network 51 which establishes a feedback loop. The output of op amp 49 is connected to the positive input of op amp 52, and the respective negative input is connected to the wiper contact of a potentiometer 53. When the voltage level of the output signal of the op amp 49 falls below a level set by potentiometer 53, indicative of a decrease in the fluid pressure on sensor 47 and a loss of coolant flow, the output of op amp 52 goes low, and the system reset switch 82 is disabled to stop all power to the laser pumping light source. Thus the laser output is stopped immediately.
A further safety circuit, shown in FIG. 2, is designed to prevent excessive heat in the laser system or in a laser beam receiving target from destroying system components by shutting off the laser when an excessive temperature condition is detected. The thermal safety circuit 56 includes an infrared sensitive photosensor 57, such as an infrared diode sensor, with its terminals connected across the inputs of an op amp 58. In a preferred embodiment of the invention, the infrared sensor may be directed to the transfer system that conducts the laser beam from the laser to a delivery system, such as fiberoptic beam guide that extends to a beam utilization device. An example of one such transfer system is described in copending U.S. patent application Ser. No. 07/180,950, filed on Apr. 11, 1988 by the present inventor, Dan Rink, and Garrett Lee, now U.S. Pat. No. 4,925,265, issued May 15 1990. The disclosure of that patent is incorporated herein by reference. In that apparatus there is a bushing component that supports the ends of a plurality of optical fibers while the focused laser beam is shifted among the plurality of fiber ends. Any misalignment of the focused beam can direct a focused laser pulse of extremely high power density onto the busing component, quickly generating very high temperatures that cause the emission of infrared light. The sensor 57 picks up the infrared light, and emits a proportional voltage in response thereto. Alternatively, the sensor 57 can be directed to monitor the infrared output of a beam-receiving target member, such as a laser heated cautery cap for recanalization of atherosclerotically occluded vessels, as described in the copending U.S. patent application Ser. No. 07/019,755, filed Feb. 27, 1987 and noted above.
The output of op amp 58 is connected to a solid state switch 59, which has a trigger input connected to the firing signal C 2 . Switch 59 is connected in turn to the positive input of op amp 61, which is provided with a direct feedback loop 62 from output to input. The configuration of op amps 58 and 61 is such that the current level of the output of op amp 61 is proportional to the infrared radiation received by sensor 57. This current output signal is fed through resistor 63 to one input of op amp 64, so that the current through resistor 63 is a function of the magnitude of the infrared radiation. Op amp 64 includes a feedback capacitor 66 which integrates the current input to produce an output having a voltage proportional to the total infrared power received by the sensor, which in turn is indicative of the temperature of the component being sensed. Solid state switch 67 is connected in parallel with capacitor 66, and includes a trigger input connected to C 2 . It should be noted that the firing signal C 2 causes the switch 67 to reset the integration product to zero prior to each laser pulse. Furthermore, the switch 59 connects the infrared signal to the integrator only during the brief firing signal, before the laser pulse is fired. This arrangement assures that the infrared source is monitored only when it is not being illuminated by the laser, which would overwhelm the infrared signal of interest.
The output of op amp 64, a voltage analog of the infrared power level and hence an indication of temperature level, is connected to one input of a comparator 68, and the output of comparator 68 is conducted through diode 69 to one of the reset inputs 32R. Comparator 68 includes a level-setting potentiometer 70 connected to the other input. Thus as the temperature of the monitored component increases, the voltage output of op amp 68 decreases, and when it fails to exceed the threshold of potentiometer 70 the output of op amp goes low and pulls the AND input 32R to a low state. This circuit effectively monitors the temperature of a component after a laser pulse, and serves to limit or chop the duration of the next successive laser pulse in response to the previous temperature level. For example, an excessive temperature condition in the component being monitored would cause the system to emit only a brief pulse in the next laser pulse cycle.
The present invention also includes a high voltage lamp driver circuit for operating the flashlamp or the like that optically pumps the laser rod to emit a coherent beam. With regard to FIG. 7, the lamp driver circuit includes a transformer 81 connected through a main shutoff relay switch 82 to 117 VAC utility power. The transformer 81 includes a high voltage secondary winding 83 having an output of approximately 600 volta that is connected across a full wave bridge rectifier 84. The rectified voltage is fed to a flashlamp current control circuit 86, which includes filter capacitors that produce a smooth DC current that in turn is connected to one electrode of a flashlamp 87. The other electrode of the flashlamp is connected to one output terminal of the rectifier 84. The circuit 86 applies approximately 160 VDC to the flashlamp to maintain the lamp plasma in a conductive state, emitting light at a level well below the threshold of lasing in the NdYAG rod. The current control circuit is also connected to a spark transformer 88, which has a high voltage output connected to a spark electrode 89 adjacent to the flashlamp 87. The spark transformer is activated by circuit 86 to provide a high voltage pulse to initiate flashlamp conduction, after which the circuit 86 provides a steady "simmer" current to maintain conduction in anticipation of a high current pulse to dramatically increase flashlamp output and initiate lasing.
To provide the high current pulse, the river circuit includes another full wave bridge rectifier 91 connected across the utility power supply. One output terminal of the rectifier 91 is connected to one electrode of the flashlamp, and the other output is connected to the drain terminals of a plurality of power MOSFETs 92 in a parallel configuration. The source connections of the MOSFETs 92 are connected in parallel fashion to the other flashlamp electrode. Thus switching of the MOSFET devices causes the output of the rectifier 91 to be applied directly across the flashlamp, and this branch of the circuit provides the substantial current required to sustain the output of the flashlamp at levels necessary to cause lasing.
Switching of the MOSFETs 92 is accomplished by signal C 3 , which is fed to an opto-isolator 93 to isolate the logic circuits for the power circuits. The output of the isolator 93 is conducted to a two stage inverter, comprising gate 94 connected in series with a parallel array of gates 96. This double inverter arrangement comprises a high current source required to overcome the intrinsic gate-to-channel capacitance and switch the MOSFETs 92 as rapidly as possible. The outputs of gates 96 are connected together and lead to the gate connections of the MOSFETs 92. Thus whenever signal C 3 goes high, the MOSFETs 92 are switched on to provide high current to the flashlamp to sustain the lamp output as long as C 3 remains high. As soon as C 3 drops to zero, the MOSFETs switch off, lamp output ceases, and the maintenance voltage increases once again.
It may be appreciated that the control system of the present invention is closely tied to the utility power supply, not only in terms of voltage and current requirements, but also for timing control and repetition. Each half-cycle of the sinusoidal power wave provides a timing signal for the system, and the laser will fire repetitively, once each half cycle, as long as the system is turned on and none of the safety circuits are activated. Each pulse will have a maximum period set by the circuit of FIG. 1, and an actual period set by the laser power sensing circuit of FIG. 4.
A further safety circuit, shown in FIG. 5, is designed to shut off the laser system when excessive current is detected in the power circuit feeding the flashlamp. It includes a Hall effect transducer 101 which is disposed about one of the conductors connected directly to the flashlamp and adapted to sense the magnitude of the magnetic field created by the current flow in the conductor. The output of transducer 101 is conducted to op amp 102, which in turn has an output connected through a resistor to the negative input of op amp 103. Op amp 103 is provided with a parallel combination of a capacitor 104 and solid state switch 106 connected between the output and negative input. The capacitor integrates the current generated by the transducer to produce a voltage signal output on signal line 100 proportional to the current flow to the flashlamp. The solid state switch 106, which is triggered by signal C 2 resets the integration product to zero prior to each laser pulse.
The output of op amp 103 is compared to an adjustable voltage reference 107 by comparator 108, the output of which is connected to one of the reset AND inputs 32R. Thus whenever the current to the lamp exceeds a selected maximum level, the laser is extinguished in the midst of an output pulse. The voltage produced by the potentiometer 107 sets the maximum current level permitted in the flashlamp driving circuit.
The voltage signal output on signal line 100, proportional to the current flow to the flashlamp, is also conducted to op amp 111, wherein it is compared with a further adjustable voltage reference 112. As before, the voltage level of reference 112 establishes a maximum current level sensing circuit. However, the output of op amp 111 is connected to the actuating input of relay switch 82, so that an excessive current condition in the flashlamp driver circuit will shut off power to the entire laser system. Thus not only is the laser pulse terminated by a high current condition (by op amp 108), but the entire laser control and driving system is disconnected from the utility power supply. This feature assures that any malfunction or short circuit will be neutralized immediately, no shock hazard will develop, and the system components will be protected.
The signal line 100 is further extended through resistor 113 to one input of op amp 114. This input is also connected to an RC integrating network 116, which produces a long-term average of the power consumed in the flashlamp driving circuit. This circuit detects current flow over the average of many laser pulses, and is provided as a further safety precaution to prevent excessive current flow.
Another salient feature of the present invention comprises a novel approach to safe use of a laser in medical or industrial settings. Generally speaking, it is necessary for all personnel to wear laser safety goggles which block light radiation in a narrow range of the laser output. These goggles comprise a large expense for a group of people, such as the operating team in a surgery. Furthermore, the goggles often are distracting and annoying, especially for individuals who wear eyeglasses.
In the present invention, these problems are alleviated by the provision of a further safety circuit shown in FIG. 8. This circuit, the laser radiation area detector, includes a photosensor 121 disposed adjacent to the housing in which the laser is enclosed, and directed obliquely toward a wall or ceiling surface in the room in which the laser is being used. The photosensor 121 may comprise a silicon photodiode or the equivalent, and is provided with a primary filter 122 that has a narrow optical passband in the range of the laser radiation. For example, commonly available filters transmit approximately 40% of light energy in the NdYAG output band, and only 1% of the remainder of the optical spectrum. The output of the photosensor, a current signal having a magnitude which is a function of the amount of laser light received by the sensor 121, is connected across the inputs of op amp 123. The output of op amp 123 is fed to differentiating capacitor 124, which in turn is connected to an input of AND gate 126.
Also connected to the same input is a parallel network comprised of a resistor and a diode extending to ground. The capacitor, in combination with this network, determines that a signal C 5 will appear on the input of gate 126 only when an abrupt negative change occurs in the amplitude of light in the narrow band of the laser output. (See also FIG. 6.) The component values are chosen so that the output signal C 5 will comprise a brief pulse, on the order of microseconds, in response to the photosensor 121 receiving a sudden negative change in the ambient light level in the laser output band. Since virtually any broadband light source will emit some light energy in the laser output band, and this output can vary, it is important to distinguish sudden negative changes in the output band level that are indicative of laser pulse energy escaping into the area surrounding the laser itself.
The laser radiation area detector also includes a timer 131, such as the standard 7555 timer known in the prior art, which is connected through resistor-diode network 132 and capacitor 133 to signal C 3 . Timer 131 is configured to produce a short output pulse C 4 , on the order of a few microseconds, immediately after signal C 3 (actually, RC3, since the signal is modified in duration by the various inputs to reset AND gate 32) goes to zero and the laser pulse has ended for that respective cycle, as shown in FIG. 6. Signal C 4 , which effectively comprises a time window during which the ambient light signal is sampled and detected, is also input to the AND gate 126. When signals C 4 and C 5 are coincident in time, as shown in FIG. 6, AND gate 126 is actuated to produce an output signal during this signal convergence. Thus the gate 126 produces an output only when the photosensor 121 picks up an abruptly falling amplitude of area illumination in the laser output band, and only when this negative change occurs immediately after the cessation of a laser pumping, as the laser output is rapidly decreasing. Such convergence is a reliable indication of the escape of laser radiation into the area near the laser.
The output of gate 126 is fed through diode 136 to an integrating network 137 comprised of a resistor and diode connected in parallel to ground. It is also connected to an inverting gate 138 which has its output connected to the system reset switch 82. The integrating network 137 determines that more than one output pulse from AND gate 126 is required to trigger a signal from gate 138 to actuate switch 82 and shut off the laser system. In the preferred embodiment the component values are chosen so that two output pulses from gate 126 are required to shut off the laser system.
Due to the fact that the safety circuit of FIG. 8 reliably distinguishes laser radiation from background light and ambient light, including fluorescent lights, surgical lights, photographic flash lamps, sunlight, and the like, the use of laser safety goggles may be obviated.
The method of the present invention for controlling a laser is embodied in the functional description of the invention and in the operation of the various circuits described herein. The underlying concept in the method is the use of the AC power signal from the utility source, both as a power source and as a timing signal to drive a pulsed laser medium repetitively in synchronism with the AC power signal. The method of the present invention further includes the functional aspects of the laser safety circuits, for sensing temperature, power, and coolant flow, and in particular the laser radiation area detector that senses a decrease in area illumination in the laser output portion of the light spectrum in coincidence with termination of each laser pulse.
A further safety circuit of the present invention, depicted in FIG. 9, is designed to detect a break, fracture, or similar fault in an optical fiber delivery system connected to the output of the laser system. An optical fiber delivery system may be used to transmit the laser output to an intravascular cautery cap used for laser angioplasty, or a laser surgical too, or the like. As shown in FIG. 10, a plurality of laser pulses, occurring during control pulses RC 3 , are used to heat an operating tip or tool element at the distal end of an optical fiber. The temperature of the operating tip, depicted by line T, tends to increase in stepwise fashion, with each laser pulse increasing the temperature and each quiescent period providing a small amount of cooling. Over the course of a few pulses the operating tip will heat to a nominal functioning range.
In contrast, a broken or fractured optical fiber exhibits a much different temperature characteristic. When an optical fiber breaks or fractures, some of the laser energy will radiate from that point, illuminating the adjacent jacket material of the fiber. The jacket material will rapidly heat to incandescence, as shown by line T b in FIG. 10, defining a temperature spike. Due to the low thermal mass of the jacket material, the incandescence will decay very rapidly after the laser beam is turned off. The black body radiation from the hot jacket material can be sampled just after a laser pulse finishes and before the jacket material cools significantly, and this radiation can be distinguished from the radiation from the heated tip of the surgical tool.
Returning to FIG. 9, the fiber break detector includes a timer circuit comprising a timer 131', such as a standard dual timer module known in the prior art, which is connected through resistor-diode network 132' and capacitor 133' to signal C 3 . Timer 131' is configured to produce a short output pulse C 6 , on the order of a few microseconds, shortly after signal RC 3 goes to zero (FIG. 10) and the laser pulse has ended for the respective cycle. The timer component values are selected so that the pulses C 6 are delayed sufficiently after the end of signal RC 3 to permit the laser pulse to extinguish, and to capture the timer interval in which incandescence of the fiber jacket would occur in the event of a break of fracture in the fiber.
The fiber break detector circuit includes an infrared sensitive photosensor 157, such as an infrared diode sensor, with its terminals connected across the inputs of an op amp 158. The infrared sensor is directed to receive infrared emissions from the optical fiber delivery system. The sensor 57 picks up the infrared light, and emits a proportional voltage in response thereto. The output of op amp 158, which is a temperature signal having a magnitude proportional to the temperature detected by the sensor 157, is connected to a solid state switch 160, which has a trigger input connected to the firing signal C 6 . Thus the signal is conducted only during the brief period after the laser pulse is extinguished.
The temperature signal is conducted to one input of op amp 168, the other input being a voltage reference 170 that sets a threshold level. When the temperature signal exceeds the threshold level, the op amp 168 produces a signal that is conduced through blocking diode 169 to the reset gate 32R. Thus a temperature signal which exceeds an empirically determined threshold will cause the laser to stop immediately, so that damage due to a broken or fractured fiber will be minimized. | A control apparatus for a pumped rod-type laser includes an arc lamp disposed to illuminate the lasing medium, such as a NdYAG crystalline rod. The apparatus includes a full wave rectifier to power the arc lamp, and a MOSFET switching circuit to turn on and off the arc lamp power at controlled times during each half cycle of the power waveform so that the laser medium is pumped and optically discharged once during each half cycle of the power supply. The laser power output is measured by a photodetector during each half cycle, and the photodetector output is integrated and compared with a manually set, variable laser output power level. When the actual laser power reaches the preset power level, the comparator initiates turning off the MOSFET switching circuit power for that respective half cycle of the power waveform. The apparatus also includes safety circuits that permit laser operation only when the internal cooling system is operating, when the current to the arc lamp is below a maximum level, and when the temperature created by the laser illumination on a target is below a variable preset level, and the like. A further safety circuit detects the presence of laser radiation in the area surrounding the laser to shut it off when laser light escapes from the system. For medical uses, this feature obviates the need for laser safety goggles for operational personnel. | 0 |
BRIEF DESCRIPTION OF THE INVENTION
The present invention relates to a method of controlling a weaving machine yarn feeding device having a drive motor for driving a rotatable winding element, the drive motor when controlled to stop being further driven at slow speed independent from yarn consumption in a winding direction during a crawl phase for a predetermined time or angle.
BACKGROUND OF THE INVENTION
According to a method known from EP 05 80 267 A the drive motor of the yarn feeding and measuring device first is strongly decelerated to the low speed of the crawl phase and then is rotated further at slow speed for a predetermined rotation angle or a predetermined time duration and then is stopped at the end of the crawl phase to prevent the formation of loops in the yarn between the storage bobbin and the winding element. The strong deceleration of the drive motor and the inertia of the yarn result in a relaxation of the yarn between the storage bobbin and the winding element which relaxation may lead to a loop formation. This danger is particularly high when the drive motor is decelerated very strongly from high or maximum speed. During the subsequent restart of the drive motor depending on consumption the yarn is stretched abruptly which might cause a yarn breakage. The crawl phase directly continuing the deceleration phase either prevents that a loop will be formed or stretches an already formed loop.
According to the method known from EP 02 61 683 A a crawl phase directly continues a deceleration of the drive motor of the yarn feeding device down to crawl speed which crawl phase then is carried on for e.g. 200 ms. The purpose of the crawl phase is to prevent the occurrence of kinks in the yarn between the winding element and the storage surface, or to suppress slackness of the yarn in this area which may be caused by a backturn motion of the winding element counter to the normal winding direction.
Both known methods are based on the task either to suppress a loop formation occurring with the deceleration of the drive motor or to remove a loop already prior to the stop of the winding element. The crawl phase conventionally is controlled by a software pre-adaptation of the control device, however, by doing so it may be complicated to determine the start of the crawl phase precisely enough with the still running drive motor, since the drive motor may have differing run out phases depending on the operational conditions and the yarn quality, respectively. To assure that during the crawl phase a sufficient yarn length is pulled into the yarn feeding device, the crawl phase is adjusted for security reasons longer than necessary. For weaving machines operating with high insertion frequencies and extremely high yarn speeds in the yarn feeding device, however, it is important to stop the drive motor as rapidly as possible, in case that the number of windings stored in the yarn feeding device reaches the maximum and when at the same time no yarn consumption takes place. A crawl phase, which, however, is too long for safety reasons easily may result in an overfilling of the yarn feeding device. The static friction to start the yarn from stand still must be overcome in any case for a restart and also the static start friction in the drive motor.
It is an object of the invention to provide a method of the kind as disclosed herein which allows a correct yarn control at the inlet side of a weaving machine yarn feeding device in a simple and different manner.
The invention is considering the recognition that a relaxation of the incoming yarn during deceleration of the drive motor first neither is particularly critical for the yarn nor for the yarn feeding device or the weaving machine downstream of the yarn feeding device, but only is critical for the subsequent re-start. The yarn relaxation occurs due to the inertia or the elasticity of the yarn. Bearing this recognition in mind, the crawl phase for a predetermined rotation angle or a predetermined time duration thus is carried out after the stand still condition and so to speak in peace. For that reason, according to the method, first the drive motor is brought to stand still completely, and particularly because of the danger of an overfilling as rapidly as possible, and then the time duration available between the stand still condition and the subsequent re-start depending on consumption is utilised to carry out the crawl phase for the precise time duration or the exactly needed rotation angle, respectively. This is simpler in terms of control technique. Experience has namely proven that always a sufficiently long time duration will be available after the drive motor has been stopped from high speed. A yarn relaxation is tolerated intentionally, which might be caused by inertia, by a backturn motion of the winding element due to the yarn tension, or for other reasons, in order to first assure a rapid stop of the drive motor and to avoid overfilling of the yarn feeding device, and a measure is started first at a later point in time to omit the potential dangers of a formed loop which was particularly dangerous for the subsequent re-start.
According to the method the crawl phase is carried out for a predetermined time duration and with a predetermined speed timewise between a stand still depending on consumption and the subsequent re-start also depending on consumption or yarn demand. In this case the crawl phase speed either may be constant or variable.
Particularly, the weaving pattern during a multi-colour weaving operation may dictate longer stop pauses for a yarn feeding device feeding a certain colour. In the case that the yarn tends to relax during a longer pause, e.g. by pulling back the winding element counter to the normal winding direction, it may be expedient to associate the crawl phase timewise not to the braking phase but to the re-start, i.e., to carry out the crawl phase first immediately prior to the subsequent re-start such that a correct yarn control is guaranteed when the drive motor is restarted.
In this case it may be expedient to adjust the timewise termination of the crawl phase exactly to the point in time or even shortly after the point in time of the subsequent re-start. This may result in the advantage that the incoming yarn still may be in motion during the subsequent re-start and has not reached a condition in which the yarn or the winding element, respectively, has to overcome static starting friction. A sliding transition from the crawl phase with optionally increasing speed into the subsequent re-start is particularly advantageous for delicate yarn qualities. In this case no static starting friction has to be overcome in the drive motor as well such that the drive motor may accelerate more forcefully.
The re-start phase of the drive motor basically may contain the previous crawl phase in order to fully accelerate without stand still already from the crawl phase speed. Such a combined re-start phase e.g. is triggered by the consumption depending start signal for the drive motor and is then made by a corresponding control routine. In this case the crawl phase does not need to be controlled separately. There is no static starting friction which has to be overcome. The drive motor can be accelerated more efficiently.
Basically it is expedient to know the point in time of the subsequent and consumption depending re-start in order to precisely adapt the crawl phase thereto. This is achieved according to a further variant of the method by providing weaving pattern dependent information and to transmit the same to the control device, the information indicating at which point in time or at which rotation angle value, e.g. of the driving,shaft of the weaving machine or after how many upcoming insertion cycles the driving motor of this yarn feeding device again has to re-start. On the basis of this information the crawl phase can be carried out precisely and optimally, particularly also such that a sliding transition will take place from the crawl phase into the consumption depending subsequent re-start.
By this pre-information of the control device of the yarn feeding device a prerequisite is set for adjusting the timewise termination of the crawl phase even shortly before, precisely on or shortly after the point in time at which the consumption depending subsequent re-start will take place. This allows not only to effect a sliding transition into the subsequent re-start, but even allows to adjust the crawl phase precisely such that then only so much yarn is pulled into the yarn feeding device sufficient to compensate for a potential loop formation.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the object of the invention will be explained with the help of the drawings. In the drawings:
FIG. 1 is a schematic view of a yarn processing system which includes as basis components a yarn store, a weaving machine—feeding device and a weaving machine,
FIGS. 2-4 are speed/time diagrams related to the control operation of the yarn feeding device in different variants of the method.
DETAILED DESCRIPTION
A yarn processing system S includes in FIG. 1 a yarn store 1 , e.g. a storage bobbin, for a yarn Y wound on the storage bobbin, a yarn feeding device F which pulls off the yarn Y from the yarn store 1 and intermediately stores the yarn in windings, and a yarn processing textile machine, e.g. a weaving machine W in the form of a gripper weaving machine or a projectile weaving machine or an air jet weaving machine or a water jet weaving machine, into the weaving shed 2 of which the yarn Y intermittently is inserted as the weft yarn during subsequent discrete insertion cycles. FIG. 1 only shows one yarn feeding device F. However, several yarn feeding devices F may be functionally associated to the weaving machine W which several yarn feeding devices F may be operated according to a predetermined sequence or depending from the weaving pattern.
The yarn feeding device F contains in a housing 3 an electric drive motor M for a winding element 4 . In the figure the incoming yarn Y is entering the winding element 4 from the left side and substantially linearly. The winding element 4 deflects the yarn Y outwardly and intermediately stores the yarn Y in adjacent yarn windings on a storage body 5 . In the shown embodiment of the yarn feeding device the storage body 5 is provided stationarily. The yarn, optionally via a central withdrawal eyelet O, is withdrawn from the storage body 5 by a not shown insertion device of the weaving machine W. Instead the yarn feeding device may be provided with a rotatably driven storage body. This respective yarn feeding device F is intended for use at a gripper weaving machine or a projectile weaving machine, or may be designed as a measuring-feeding device for an air jet weaving machine or a water jet weaving machine, respectively.
An electronic control device C is associated to the drive motor M, and e.g. is arranged in housing 3 . The control device C is connected to sensors 6 sensing the number of windings or the size of the intermediate store on the storage body 5 and transmitting corresponding signals to the control device C which re-starts the electric motor M consumption depending or depending on yarn demand. The control device C accelerates the drive motor, controls a predetermined speed, decelerates or even brakes and stops the drive motor and keeps the drive motor stopped during consumption depending on resting periods. As soon as the number of windings on the storage body 5 reaches a predetermined maximum value while the drive motor runs at maximum speed in a predetermined winding direction, the number of windings is detected by the frontside sensor. Then the drive motor has to be stopped as rapidly as possible. In case that, due to consumption, the number of windings on the storage body 5 drops below a predetermined number, the other sensor responds such that the control device C either accelerates the still running drive motor M or accelerates the drive motor M from standstill and with a predetermined characteristic of the acceleration or the re-start, respectively. Furthermore, the control device C may be programmed such that it subsequently adjusts a substantially continuous speed of the drive motor just sufficient to continuously replenish the consumption by the weaving machine w without stand still periods. In case of a so-called multi-colour weaving process with several yarn feeding devices F there might be frequently longer stand still periods for some of the yarn feeding devices depending on the weaving pattern.
FIG. 1 indicates a control assembly C 1 which may be associated to the weaving machine W and which provides weaving pattern depending information which, expediently, may be transmitted to the control device C of the yarn feeding device. Such information e.g. may indicate the respective yarn feeding device F that after expiration of a predetermined time or a number of insertion cycles after transmission of the information no further consumption or new consumption will take place for a predetermined time or during a predetermined number of insertion cycles. Then the control device C may, in order to avoid abrupt condition changes in the yarn feeding device, which could be dangerous for the yarn, carry out a special preparatory control of the drive motor M. In case that the transmitted information indicates that the yarn feeding device will be taken out of consumption in a short while, then the control device may already lower the still high speed of the drive motor in advance in order to avoid a later abrupt stop. In case that the information indicates when again strong consumption and in connection therewith a re-start under full acceleration is to be expected, then the control device may start the drive motor with slow speed and in advance to avoid a later sharp re-start jerk. It is further possible to use the transmitted pre-information to preparatorily increase or decrease the running speed of the running drive motor.
During the run of the drive motor M particularly at high running speed, the yarn Y substantially is pulled from the yarn store 1 linearly and runs in stretched condition into the winding element 4 . When a response of the frontmost sensor 6 rapidly stops the drive motor M, e.g. because the number of yarn windings has reached the maximum allowable value, then the drive motor M will be forcedly braked to stop such that the maximum value will be exceeded as little as possible. Due to inertia the incoming yarn Y from the bobbin then may relax during the stop procedure such that it forms a loop L e.g. between the yarn store 1 and the winding element 4 . A slack yarn section also may be produced between the winding element 4 and the storage body 5 . After the drive motor stop the tension present in an elastic yarn may turn back the winding element 4 until the yarn will be relaxed as well. As soon as at a later point in time the drive motor re-starts depending on yarn consumption, such a slack yarn again will be stretched abruptly which easily results in a yarn breakage. Another danger is that loops or kinks formed due to the relaxation of the yarn during the stand still period will be transported into the windings on the storage body 5 and further even into the weaving shed 2 of the weaving machine.
To avoid such malfunctions a crawl phase with low speed is controlled during the stand still phase for the drive motor by the control device C. The crawl phase is characterised in that the drive motor is rotated at very low and constant, at varied or at increasing speed during a predetermined time duration or over a predetermined rotation angle of the winding element 4 in winding direction to reliably stretch out relaxed sections of the yarn Y between the storage 1 and the storage body 5 or to even intentionally build-up a predetermined yarn tension in those sections, respectively.
According to the invention, however, the crawl phase is controlled in FIG. 2 first after the true stop of the drive motor M and of the winding element 4 . The crawl phase even may be associated to the upcoming consumption depending subsequent re-start of the drive motor M.
A curve 6 shown in FIG. 2 (speed/time diagram or weaving machine rotation angle diagram) represents the run of the drive motor M at high speed before the control device C emits at a point in time t 1 a command for a stop, e.g. because the frontmost sensor 6 has responded. Due to inertia the drive motor M or the winding element 4 , respectively, then stop at point in time t 2 . At point in time t 3 after t 2 the crawl phase represented by a curve 8 is controlled such that the crawl phase extends over a predetermined time duration (from t 5 to t 4 ) or over a predetermined rotation range of the winding element 4 . The crawl phase is made with slow speed, preferably with essentially constant or slightly varied speed. As soon as the crawl phase is terminated at point in time t 4 , the consumption depending subsequent re-start of the drive motor, e.g. with strong acceleration, occurs at point in time t 5 (curve 7 ). A loop L in the yarn occurring earlier at point in time t 2 or t 3 then is removed during the crawl phase such that a correct yarn control will be possible during the subsequent re-start.
The control the control device C may set a predetermined time duration (t 1 to t 3 ) after the initiation of the crawl phase and at the point in time t 1 of the stop signal, or the control device C may set a corresponding rotation angle range of the main shaft of the weaving machine W, respectively. The respective time duration or the rotation angle range is selected such that the individual deceleration property of the drive motor and the winding element and other components rotating therewith will be considered such that the crawl phase first starts after the true stop of the drive motor at point in time t 2 . It may be expedient to adjust the end (point in time t 4 ) of the crawl phase close to the consumption depending subsequent re-start (point in time t 5 ) to remove any relaxation of the yarn, even relaxations which occurred during a longer stand still phase. The indirect triggering action for the crawl phase is the stop signal emitted at point in time t 1 . Alternatively, the crawl phase could be controlled even by a cycle generator including a counter or by a clock. In case that the yarn feeding device is operating relatively regularly with stand still periods of essentially equal durations, the control device C could carry out the crawl phase (curve 8 ) within each stand still period and by corresponding software preparation such that the prerequisites e.g. as shown in FIG. 2 will be fulfilled.
FIG. 3 the crawl phase represented by the curve 8 is integrated into the motor re-start phase such that a sliding transition is achieved from the crawl phase into a strong re-start acceleration. In this case the re-start phase of the drive motor M is set by the control such that upon-occurrence of the start signal for the drive motor at point in time t 5 automatically first the crawl phase, optionally with increasing speed, is carried out and that with a sliding transition further acceleration is controlled starting at point in time t 6 without an immediate stop. In this case no static starting friction of the yarn and no starting friction torque for the drive motor during the re-start have to be overcome. In other words, to the benefit of the crawl phase the strong re-start acceleration is somewhat delayed after point in time t 5 .
Stand still periods may have different time durations depending on consumption. For that reason and according to FIG. 4 (and as explained for control arrangement C 1 in FIG. 1 ) information may be transmitted at a point in time t 6 to control device C, e.g. from a control system monitoring the weaving pattern, that yarn consumption will cease in a short time, and that then at a later point in time t 5 or shortly after t 5 again yarn consumption will start from the feeding device. On the basis of this information defining the stand still phase the control device C is able to control the crawl phase such that it is carried out within the stand still period e.g. close to point in time t 5 for the consumption depending re-start and such that the crawl phase either is completely carried out until then or will terminate directly at point in time t 5 or even terminates with its final phase t 4 overlapped with point in time t 5 . In both just described cases the yarn has not stopped when the drive motor re-starts (sliding transition). This means that the yarn is treated tenderly or that the drive motor can be accelerated more efficiently, respectively.
To correctly adjust the crawl phase the control device after having received the pre-information may calculate e.g. the point in time t 3 (if needed even also t 4 ′, t 4 ″) substantially at point in time t 1 and then controls the crawl phase accordingly.
In each case the drive motor M and the winding element 4 first are truly stopped at point in time t 2 , prior to initiating the crawl phase. This may be made according to routine with the help of the stop signal at point in time t 1 or with the start signal at point in time t 5 , or individually on the basis of the pre-information.
Although a particular preferred embodiment of the invention has been disclosed in detail for illustrative purposes, it will be recognized that variations or modifications of the disclosed apparatus, including the rearrangement of parts, lie within the scope of the present invention. | The invention relates to a method for the control of a power-loom yarn feed device, whereby a drive motor for a rotating winding element is accelerated, decelerated or stopped, on demand, for yarn storage and, in order to avoid slack yarn during the stopping of the motor, the motor is independently driven slowly during a crawl phase, such that the motor is first stopped and then after stopping is slowly rotated in the crawl phase. | 3 |
FIELD OF THE INVENTION
The present invention relates to computer security in general, and, more particularly, to authentication for wireless telecommunications terminals.
BACKGROUND OF THE INVENTION
Wireless telecommunications terminals (e.g., cell phones, personal digital assistants [PDAs] with wireless capabilities, notebook computers with wireless capabilities, etc.) are increasingly being used in the workplace for job-related tasks. Some enterprises have deployed software applications that execute on a server and can be accessed by workers via their wireless terminals. Such applications are commonly referred to as wireless web-based applications or wireless client/server applications, depending on whether or not a browser is used as the user interface on the wireless terminals.
In some domains, such as health care, it is especially convenient for workers to use hands-free wireless terminals so that using the wireless terminal does not interfere with their other job duties. When a hands-free wireless terminal is used to access a wireless client/server application, typically the user issues voice commands in lieu of keypad inputs and receives audio responses in lieu of a video display.
FIG. 1 depicts illustrative telecommunications system 100 in the prior art. As shown in FIG. 1 , telecommunications system 100 comprises telecommunications network 105 , hands-free wireless terminal 110 , and server 120 , interconnected as shown.
Telecommunications network 105 is a network that comprises one or more wireless elements (e.g., wireless access points, wireless base stations, etc.) and is capable of transporting signals between server 120 and other devices, such as hands-free wireless terminal 110 .
Hands-free wireless terminal 110 is a device that is typically worn on a user's person (e.g., clipped to one of the user's ears, etc.) and is capable of wirelessly transmitting and receiving electromagnetic signals to and from telecommunications network 105 via a wireless transceiver; of receiving voice inputs and converting them to electromagnetic signals via a microphone; and of converting electromagnetic signals to acoustic signals and outputting the acoustic signals to the user via a speaker.
Server 120 is a data-processing system that is capable of executing one or more software applications and of receiving and transmitting signals via telecommunications network 105 .
In some instances it is desirable for security reasons to require that users are authenticated before being allowed to access an application or other resource on a server. Typically a user is presented with an authentication challenge, and the user must supply a valid response to the challenge. A classic challenge/response mechanism, colloquially referred to as “logging in,” is to prompt a user to respond with his or her username and password. This mechanism is not well-suited for hands-free wireless terminals, however, because it requires that a user say his username and password aloud, and it is often difficult for the user to ensure that no one else overhears this information.
Other authentication techniques of the prior art are also poorly suited to hands-free wireless terminals. In one such technique, a user uses an electronic token device or a list of numbers to respond to an authentication challenge with a one-time password response. While this eliminates the problem of the password being overheard, it requires the user to carry around and consult the token device or list, thereby largely negating the advantage of having a hands-free terminal. In another technique, speaker recognition, a user is authenticated by comparing his or her speech to a database of known speakers. The disadvantages of speaker recognition are two-fold: first, it suffers from high error rates—particularly in the noisy environments that typically predominate in workplaces—and second, it is possible for another person to record a user's voice and play back the recording to impersonate the user.
Therefore, what is needed is a secure authentication technique for hands-free wireless terminals that overcomes some of the disadvantages of the prior art.
SUMMARY OF THE INVENTION
The present invention is a secure method of authenticating users of hands-free wireless terminals, without some of the disadvantages of the prior art. In particular, a user is authenticated by instructing the user to travel to a geo-location, where the geo-location is referred to by an identifier that the user has previously associated with the geo-location. When the user chooses identifiers that are meaningful to the user, but that do not indicate the associated geo-locations to other people the user can be securely authenticated via the following procedure:
(i) select one of the identifiers that the user has defined, (ii) instruct the user to “go to <identifier>,” and (iii) declare the user authenticated if and only if the user visits the geo-location associated with <identifier>, before a timeout expires.
For example, a user might assign the identifier “favorite hangout” to the geo-location of Starbucks store number 28,453. When challenged with the instruction “go to favorite hangout,” the user knows exactly where to go, but presumably another person will not. Even if an observer is aware of the authentication procedure and sees the user going to Starbucks store number 28,453, this does not give the observer the information necessary to impersonate the user because the identifier “favorite hangout” is heard only by the user, so that the user has no knowledge that Starbucks store number 28,453 is associated with the name “favorite hangout.” Furthermore, if the user has defined a sufficiently large number of identifier/geo-location pairs, then it becomes very unlikely that an observer who gains possession of the user's terminal would be challenged with the same identifier “favorite hangout.”
In a variation of the illustrative embodiment of the present invention, a user is challenged with an instruction to do something at a particular geo-location. For example, the user might be instructed to “say the word ‘hello’ at favorite hangout.” Such commands can further obfuscate the authentication process and thwart a malicious observer who is spying on the user.
The illustrative embodiment comprises: transmitting an identifier I to a wireless telecommunications terminal at time t, wherein the user of the wireless telecommunications terminal has associated the identifier I with a geo-location L; and when the geo-location of the wireless telecommunications terminal is substantially the same as L at a time that exceeds t by no more than a positive threshold, storing in a memory a value that indicates that the user is authenticated.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts the salient elements of illustrative telecommunications system 100 in accordance with the prior art.
FIG. 2 depicts the salient elements of telecommunications system 200 in accordance with the illustrative embodiment of the present invention.
FIG. 3 depicts a flowchart of the salient tasks for a user of hands-free wireless terminal 210 , as shown in FIG. 2 , in accordance with the illustrative embodiment of the present invention.
FIG. 4 depicts a flowchart of the salient tasks of hands-free wireless terminal 210 , in accordance with the illustrative embodiment of the present invention.
FIG. 5 depicts a flowchart of the salient tasks of server 220 , as shown in FIG. 2 , in accordance with the illustrative embodiment of the present invention.
FIG. 6 depicts a detailed flowchart for task 540 , as shown in FIG. 4 , in accordance with the illustrative embodiment of the present invention.
DETAILED DESCRIPTION
FIG. 2 depicts the salient elements of telecommunications system 200 in accordance with the illustrative embodiment of the present invention. As shown in FIG. 2 , telecommunications system 100 comprises telecommunications network 105 , geo-location-enabled hands-free wireless terminal 210 , and server 220 , interconnected as shown.
Geo-location-enabled hands-free wireless terminal 210 is a device that is typically worn on a user's person (e.g., clipped to one of the user's ears, etc.) and is capable of:
wirelessly transmitting and receiving electromagnetic signals to and from telecommunications network 105 via a wireless transceiver; receiving voice inputs from a user and converting the input to electromagnetic signals via a microphone; converting electromagnetic signals to acoustic signals and outputting the acoustic signals to the user via a speaker; receiving one or more electromagnetic signals and estimating terminal 210 's geo-location based on these signals; and performing the tasks described below and with respect to FIG. 4 via a processor.
As will be appreciated by those skilled in the art, there are a variety of well-known methods for estimating geo-location based on received electromagnetic signals (e.g., via a Global Positioning System (GPS) receiver, via triangulation, via RF fingerprinting, etc.), and it will be clear to those skilled in the art, after reading this specification, how to make and use embodiments of the present invention for terminals that use these methods—as well as embodiments in which the estimation of terminal 210 's geo-location is performed by an entity other than wireless terminal 210 . As will further be appreciated by those skilled in the art, hands-free wireless terminal 210 might communicate via one or more protocols (e.g., Code Division Multiple Access [CDMA], Institute of Electrical and Electronics Engineers [IEEE] 802.11, Bluetooth, etc.), and it will be clear to those skilled in the art, after reading this specification, how to make and use embodiments of the present invention based on these protocols.
Server 220 is a data-processing system that is capable of executing one or more software applications, of receiving and transmitting signals via telecommunications network 105 , and of performing the tasks described below and with respect to FIGS. 5 and 6 .
FIG. 3 depicts a flowchart of the salient tasks for a user of hands-free wireless terminal 210 , in accordance with the illustrative embodiment of the present invention.
At task 310 , the user defines a set of identifier/geo-location pairs, prior to using geo-location-enabled hands-free wireless terminal 210 . As discussed above, it is advantageous for the user to define a relatively large number of such pairs, and to choose identifiers that are meaningful to the user but that do not indicate the associated geo-locations to other people. As will be appreciated by those skilled in the art, task 310 might be performed by the user in a variety of ways, such as via a browser-based application that incorporates clickable maps, or via the user visiting various geo-locations while wearing wireless terminal 210 and saying the appropriate identifier at each geo-location. In the latter method, a preliminary “initialization” phase for wireless terminal 210 might be defined that bypasses the geo-location-based authentication process, thereby getting around the “chicken and egg” problem.
At task 320 , the user uses geo-location-enabled hands-free wireless terminal 210 , and is authenticated as necessary, as described below and with respect to FIGS. 4 through 6 . As will be appreciated by those skilled in the art, in some embodiments only a subset of operations that the user attempts to perform with terminal 210 might require authentication (e.g., attempts to access a resource of server 220 , etc.), while in some other embodiments authentication might be required for any kind of use of terminal 210 .
At task 330 , the user finishes using geo-location-enabled hands-free wireless terminal 210 . As will be appreciated by those skilled in the art, in some embodiments of the present invention the user might proactively log out, while some other embodiments might automatically log out the user when the terminal is inactive for a given time interval, while still other embodiments might employ both of these methods.
After task 330 , execution proceeds back to task 320 when the user begins using terminal 210 again.
FIG. 4 depicts a flowchart of the salient tasks of hands-free wireless terminal 210 , in accordance with the illustrative embodiment of the present invention. It will be clear to those skilled in the art which tasks depicted in FIG. 4 can be performed simultaneously or in a different order than that depicted.
At task 410 , an authentication challenge is received at hands-free wireless terminal 210 , in response to the user of terminal 210 attempting to perform a particular operation with terminal 210 .
At task 420 , wireless terminal 210 transmits its current geo-location to server 220 via telecommunications network 105 , in well-known fashion. In addition, if the authentication challenge is of a type that instructs the user to do something at a particular geo-location, wireless terminal 210 also transmits any user input to server 220 .
Task 430 checks whether wireless terminal 210 has received a signal that indicates either (1) that the user has been successfully authenticated, or (2) that a timeout interval has expired and the user has not been authenticated. If either type of signal is received, the method of FIG. 4 terminates, otherwise execution continues back at task 420 .
FIG. 5 depicts a flowchart of the salient tasks of server 220 , in accordance with the illustrative embodiment of the present invention. It will be clear to those skilled in the art which tasks depicted in FIG. 5 can be performed simultaneously or in a different order than that depicted.
At task 510 , server 220 receives a signal S from wireless terminal 210 , in well-known fashion.
At task 520 , server 220 checks whether signal S requires that the user of wireless terminal 210 has been authenticated. If so, execution proceeds to task 530 , otherwise execution continues at task 550 . (As described above, in some embodiments only a subset of signals received from terminal 210 might require the user to be authenticated, while in some other embodiments authentication might be required for any signal received from terminal 210 .)
At task 530 , server 220 checks whether the user of wireless terminal 210 has been successfully authenticated. If so, execution continues at task 550 , otherwise execution proceeds to task 540 .
At task 540 , server 220 authenticates the user, as described below and with respect to FIG. 6 . After task 540 , execution continues back at task 530 .
At task 550 , server 220 processes signal S in accordance with how it is programmed, in well-known fashion. After task 550 , execution continues back at task 510 .
FIG. 6 depicts a detailed flowchart for task 540 , in accordance with the illustrative embodiment of the present invention. It will be clear to those skilled in the art which subtasks depicted in FIG. 6 can be performed simultaneously or in a different order than that depicted.
At subtask 610 , server 220 selects an identifier/geo-location pair (I, L) from the list of such pairs that were defined by the user of wireless terminal 210 . As will be appreciated by those skilled in the art, in some embodiments pair (I, L) might be selected randomly, while in some other embodiments pair (I, L) might be selected in sequential fashion, while still other embodiments might select pair (I, L) via some other method.
At subtask 620 , server 220 sets an authentication status flag for terminal 210 's user to unsuccessful.
At subtask 630 , server 220 transmits to wireless terminal 210 a signal that instructs the terminal to output the phrase “go to <I>” via the terminal's speaker. As mentioned above, in some embodiments server 220 might transmit a signal that instructs the terminal's user to perform some action at geo-location <I> (e.g., “say ‘hello’ at <I>,” “check your email at <I>,” etc.)
At subtask 640 , server 220 sets the value of variable t to the current time, in well-known fashion.
At subtask 650 , server 220 checks whether the difference between the current time and t exceeds a pre-determined threshold. As will be appreciated by those skilled in the art, the threshold acts as a timeout, and thus the value of the threshold should be selected so that the user has sufficient time to travel to geo-location <I>. If the difference exceeds the threshold, then execution continues back at task 530 of FIG. 5 (where the value of the authentication status flag will indicate whether the user was successfully authenticated); otherwise execution proceeds to task 660 .
At subtask 660 , server 220 receives the current geo-location C of wireless terminal 210 , in well-known fashion.
At subtask 670 , server 220 checks whether geo-location C is substantially the same as geo-location L, where “substantially the same” is intended to account for inconsequentially small differences between C and L (e.g., different tables in a Starbucks, etc.) If so, execution proceeds to task 680 , otherwise execution continues back at task 650 .
At subtask 680 , server 220 sets the authentication status flag for terminal 210 's user to successful. After task 680 , execution continues back at task 530 of FIG. 5 .
As will be appreciated by those skilled in the art, although in the illustrative embodiment a user is authenticated by visiting one particular geo-location, in some other embodiments a user might be instructed to visit two or more geo-locations sequentially, and it will be clear to those skilled in the art, after reading this specification, how to make and use such embodiments.
Similarly, although in the illustrative embodiment server 220 handles authentication and might also host one or more software applications, some other embodiments might employ separate servers for these two functions, and it will be clear to those skilled in the art, after reading this specification, how to make and use such embodiments.
Furthermore, although the illustrative embodiment is particularly well-suited to hands-free wireless terminals, it will be clear to those skilled in the art that the basic concepts of the present invention can also be applied to wireless terminals that are not hands-free, and it will be clear to those skilled in the art, after reading this specification, how to make and use embodiments of the present invention for such terminals.
It is to be understood that the above-described embodiments are merely illustrative of the present invention and that many variations of the above-described embodiments can be devised by those skilled in the art without departing from the scope of the invention. For example, in this Specification, numerous specific details are provided in order to provide a thorough description and understanding of the illustrative embodiments of the present invention. Those skilled in the art will recognize, however, that the invention can be practiced without one or more of those details, or with other methods, materials, components, etc.
Furthermore, in some instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the illustrative embodiments. It is understood that the various embodiments shown in the Figures are illustrative, and are not necessarily drawn to scale. Reference throughout the specification to “one embodiment” or “an embodiment” or “some embodiments” means that a particular feature, structure, material, or characteristic described in connection with the embodiment(s) is included in at least one embodiment of the present invention, but not necessarily all embodiments. Consequently, the appearances of the phrase “in one embodiment,” “in an embodiment,” or “in some embodiments” in various places throughout the Specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments. It is therefore intended that such variations be included within the scope of the following claims and their equivalents. | An apparatus and methods are disclosed for authenticating users of wireless telecommunications terminals. A user is authenticated by instructing the user to travel to a geo-location, where the geo-location is referred to by an identifier that the user has previously associated with the geo-location. When the user chooses identifiers that are meaningful to the user, but that do not indicate the associated geo-locations to other people, the user can be securely authenticated via the following procedure: (i) select one of the identifiers that the user has defined, (ii) instruct the user to “go to <identifier>,” and (iii) declare the user authenticated if and only if the user visits the geo-location associated with <identifier> before a timeout expires. | 7 |
CROSS-REFERENCES TO RELATED APPLICATIONS
This application claims priority to U.S. Provisional Application No. 61/234,530, filed Aug. 17, 2009; and U.S. Provisional Patent Application Ser. No. 61/235,506, filed Aug. 20, 2009, the subject matter of which is hereby incorporated by reference in its entirety.
The present application incorporates in their entireties U.S. Provisional Patent Application Ser. No. 61/187,137, entitled “DESIGN METHOD AND METRIC FOR SELECTING AND DESIGNING MULTIMODE FIBER FOR IMPROVED PERFORMANCE,” filed Jun. 15, 2009; and U.S. Provisional Patent Application Ser. No. 61/118,903, entitled “MULTIMODE FIBER HAVING IMPROVED INDEX PROFILE,” filed Dec. 1, 2008.
BACKGROUND
Degradation of an optical pulse propagating through an optical fiber is the result of attenuation and dispersion. Dispersion is the broadening of discrete data bits as they propagate through the media. Pulse broadening results in an overlap between sequential data bits causing an increase in the uncertainty whether a bit is interpreted as logic 0 or 1. This uncertainty in logic state is quantified in terms of bit error rate (BER), where the BER is defined as the number of error bits divided by the total number of bits transmitted in a given period of time. For high-speed Ethernet, the BER cannot exceed 1 error bit for every 1 trillion bits transmitted (BER<10 −12 ). There are two contributions to the total dispersion in multimode fiber: chromatic dispersion, or material dispersion, and modal dispersion.
Chromatic or material dispersion occurs because the refractive index of a material changes with the wavelength of light. This is due to the characteristic resonance frequencies at which the material responds to light (light is a propagating electromagnetic field). Shorter wavelengths encounter a higher refractive index (i.e., greater optical density) and consequently travel slower than longer wavelengths. Since a pulse of light typical comprises several wavelengths, the spectral components of the optical signal spread in time, or disperse, as they propagate, causing the pulse width to broaden.
Optical fiber is nearly pure silica (SiO 2 ), so the chromatic or material dispersion of fiber is essentially the same as pure fused silica. In FIG. 1 we plot the material dispersion of fused silica and the refractive index as a function of wavelength. Since the refractive index of a material is wavelength dependent, n(λ), the velocity of light in a material is also wavelength dependent related by,
v ( λ ) = c n ( λ ) ( 1 )
Where, c is the speed of light in vacuum (299,792,458 meters/second).
Referring to Equation 1, the refractive index for a short wavelength (referred to as “blue” light) is larger than that for a longer wavelength (referred to as “red” light) so that light of longer wavelengths (“red”) travels faster than shorter wavelengths (“blue”).
For light traveling through a medium with this characteristic, the effect is called “normal” dispersion. If the refractive index for shorter wavelengths is lower than longer wavelengths, the dispersion is called anomalous, as blue light will travel faster than red light.
In addition to material dispersion, optical signals traversing optical waveguides such as a multimode fiber optic cable (MMF) also undergo modal dispersion, which is generally a much larger effect in MMF. Due to the wave nature of light and the wave-guiding properties of optical fiber, an optical signal traverses the fiber along discrete optical paths called modes. The optical power of the pulse is carried by the sum of the discrete modes. With reference to FIGS. 2A and 2B , MMF is optimized so that all modes arrive at the output of the fiber at the same time. This is achieved by adjusting or “grading” the refractive index profile of the fiber core. Modes traveling with larger angles (and consequently traverse longer distances) must travel faster. These are called high-order modes. Modes traveling with small angles (low-order modes) travel slower in graded-index fiber. The difference in propagation delays between the fastest and slowest modes in the fiber is used to determine the inter-modal dispersion or simply modal dispersion.
To minimize modal dispersion, standard Graded Index Multimode Fiber (GI-MMF) is designed so the index of refraction across the core follows a parabolic distribution (referred to herein as the standard parabolic refractive index profile). The formula describing the radial distribution in refractive index for minimum modal dispersion is given by
n ( r ) = n 1 [ 1 - 2 ( r R ) α Δ ] 1 2 ( 2 )
Where α is a number close to 2 (and specific to each fiber manufacturer), R is the radius of the fiber core and Δ is given by
Δ
=
n
1
2
-
n
2
2
2
n
1
2
(
3
)
The metric used to characterize modal dispersion in MMF is Differential Mode Delay (DMD), specified in Telecommunications Industry Association Document No. TIA-455-220-A and expressed in units of picoseconds per meter (ps/m) so that the total delay is normalized by fiber length. Low modal dispersion as measured by DMD generally results in higher-bandwidth MMF. Better control in the manufacturing process produces a profile closer to the standard parabolic refractive index profile which minimizes modal dispersion. It would be desirable to make changes to the standard parabolic refractive index profile to compensate for the wavelength distribution and emission pattern of a light source to reduce modal dispersion beyond current capabilities. Furthermore, it would be desirable that these changes be included in current MMF test methods to accurately characterize DMD and fiber bandwidth.
SUMMARY
In one aspect, a method for manufacturing an improved multimode fiber optic cable which compensates for both material dispersion and modal dispersion effects is provided. The method includes, but is not limited to, coupling a laser with a reference multimode fiber optic cable and generating and launching a plurality of pulses of light radiation by the laser into the reference multimode fiber optic cable. Each pulse of light radiation is launched at different radial offset. The method also includes, but is not limited to, determining a DMD waveform profile along with a pulse delay for each pulse of light at each radial offset and determining if there are differences in pulse delays for each DMD waveform profile. The method also includes, but is not limited to, designing the improved multimode fiber optic cable with an improved refractive index profile which compensates for any differences in pulse delay present in each DMD waveform profile, and which compensates for at least a portion of the material dispersion present in the reference multimode fiber optic cable.
In one aspect, a method for designing an improved multimode fiber optic cable which compensates for both material dispersion and modal dispersion effects is provided. The method includes, but is not limited to, determining an amount of material and modal dispersion within a reference multimode fiber optic cable resulting from a pulse of light radiation launched into the multimode fiber optic cable using a laser and designing an improved refractive index profile for the improved multimode fiber optic cable which compensates for at least a portion of the material dispersion present in the reference multimode fiber optic cable.
In one aspect, a method for designing an improved multimode fiber optic cable which compensates for both material dispersion and modal dispersion effects is provided. The method includes, but is not limited to, generating and launching a plurality of pulses of light radiation into a reference multimode fiber optic cable. Each pulse of light radiation is launched at different radial offset. The method also includes, but is not limited to determining a DMD waveform profile along with a pulse delay for each pulse of light at each radial offset and designing an improved refractive index profile for the improved multimode fiber optic cable which compensates for at least a portion of the material dispersion present in the reference multimode fiber optic cable by correcting for any differences in pulse delay present in each DMD waveform profile.
The scope of the present invention is defined solely by the appended claims and is not affected by the statements within this summary.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention can be better understood with reference to the following drawings and description. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention.
FIG. 1 depicts a graph of material dispersion and a refractive index of pure silica as a function of wavelength, in accordance with one embodiment of the present invention.
FIG. 2A depicts a first cross-sectional perspective view of a graded index MMF with different mode trajectories, in accordance with one embodiment of the present invention.
FIG. 2B depicts a second cross-sectional perspective view of a graded index MMF having a standard parabolic refractive index profile that equalizes the velocities of the various modes traversing the fiber, in accordance with one embodiment of the present invention. All modes are supposed to have the same wavelength in prior models.
FIG. 3 depicts a graph of a DMD waveform to measure the difference in arrival time of all modes in a GI-MMF, in accordance with one embodiment of the present invention. From that time difference, normalized by the length of the fiber, the fiber is graded and classified to comply as OM3 or OM4 type fiber. Different colors are used for clarification purposes only. All modes have the same wavelength.
FIGS. 4A and 4B depict graphs of DMD waveform profiles of two fibers with similar DMD and EMB values, in accordance with one embodiment of the present invention. Both fibers are from the same fiber cable. Both have an EMB of 4540 MHz·km.
FIGS. 5A and 5B depict eye diagrams for Blue and Brown fibers, in accordance with one embodiment of the present invention. The eye diagram for the Blue fiber is shown in FIG. 5 a and exhibits a wider eye opening, which indicates a larger signal-to-noise ratio and therefore transmits information with fewer errors (better BER performance).
FIG. 6 depicts a graph of BER traces of Blue and Brown fibers as a function of received power, in accordance with one embodiment of the present invention. We note that for a received optical power of −9.9 dBm (minimum optical power for 10 GBASE-SR), the difference in BER performance is more than two orders of magnitude.
FIG. 7 depicts graphs illustrating that minimizing modal dispersion requires that all the modes arrive at the same time at the output end of the fiber (illustrated for two low order modes), in accordance with one embodiment of the present invention. In previous implementations, modes have been assumed to have same wavelength.
FIG. 8 depicts a graph of a wavelength dependence of a BERT Vertical Cavity Surface Emitting Lasers (VCSEL) as a function of offset from the center of a device, in accordance with one embodiment of the present invention.
FIG. 9 depicts graphs illustrating that when a wavelength variation of modes is taken into consideration, material dispersion effects, D(λ), will spread the components of a pulse even for a standard parabolic refractive index profile, in accordance with one embodiment of the present invention. The “blue” mode will arrive at the output of the fiber at a later time than the “red” mode.
FIG. 10 depicts graphs illustrating that a fiber with lower than standard parabolic index of refraction (with the standard index of refraction being indicated with a dotted line) in the outer region of the core will speed up higher order modes (“blue”), while not affecting the lower order modes (“red”) cancelling the material dispersion effects, in accordance with one embodiment of the present invention.
FIG. 11 depicts graphs illustrating that a fiber with higher than the standard index of refraction in the outer region of the core will slow down higher order modes (“blue”), while not affecting the lower order modes (“red”), exacerbating the material dispersion effects, in accordance with one embodiment of the present invention.
DETAILED DESCRIPTION
The present invention makes use of the discovery that multimode fiber optic cable having a refractive index profile may be designed to compensate for both material dispersion as well as modal dispersion when used with light sources that emit modes having different optical wavelengths in different emission patterns. The proposed multimode fiber optic cable compensates for the spatial spectral distribution of laser launch modes when coupled into fiber modes to reduce overall modal dispersion. The disclosed multimode fiber optic cable exhibits improved Bit Error Rate (BER) system performance by balancing the wavelength dependency of the VCSEL modes and the refractive index profile of the multimode fiber optic cable to reduce modal dispersion. The disclosed multimode fiber optic cable also increases the maximum reach over which a signal can be transmitted with acceptable error rates. The refractive index profile of the multimode fiber optic cable exhibits a Differential Mode Delay (DMD) waveform profile that shifts to the left (in ps/m as shown in standard graphical depictions of DMD) at larger radial offsets to compensate for a spatial distribution of emitted optical wavelengths in an optical source.
In this disclosure we relate these effects to glass optical fiber. However, this invention is equally applicable to plastic optical fiber (POF) and other waveguide structures.
Provided herein is a method for manufacturing a multimode fiber which compensates for both material dispersion and modal dispersion effects. The method first includes determining an amount of material and modal dispersion within a reference multimode fiber resulting from a pulse of light radiation launched into the multimode fiber using a laser. The method then includes designing an improved refractive index profile for the improved multimode fiber which compensates for at least a portion of the material dispersion present in the reference multimode fiber optic cable.
With reference to FIG. 3 , determining an amount of material and modal dispersion within a reference multimode fiber requires first implementing a revised DMD measurement test method, wherein a temporally short and spectrally pure optical pulse of light radiation is generated and transmitted by a laser and launched into the core of a reference MMF under test. The optical pulse of light radiation is first launched along the center axis of the fiber and an output pulse waveform is measured with a photo-detector and sampling oscilloscope. The output pulse waveform is stored for subsequent analysis. The launched optical pulse of light radiation is then displaced a small radial distance from a central core of the reference MMF, typically 1 or 2 microns, and an output waveform is again measured and recorded. This procedure is repeated across the core of the MMF from the center to a radial distance X away from the center and close to the core-cladding interface. For example, X is approximately 23 microns (±5 microns) for a 50 micron core diameter. To ensure only modes for a given radial launch offset are excited, a small diameter single-mode fiber is preferably used to launch the optical pulse of light radiation into the core of the MMF.
With reference to FIGS. 4A and 4B , an example of the resultant output waveforms for two MMF's (a Blue MMF and a Brown MMF) is shown. The waveforms for each radial offset are shown along the vertical axis, and the pulse delay of each waveform is displayed along the horizontal axis. Ideally, all pulses should arrive at the output of the fiber at the same time for the standard parabolic index profile. However, imperfections in the uniformity of the refractive index profile result in temporal shifts of the output waveforms. The DMD or modal dispersion of a MMF is calculated by subtracting the launch pulse temporal width from the difference in arrival times between the leading edge of the fastest pulse and the falling edge of the slowest pulse.
Using a standard DMD test method specified in TIA-455-220-A, MMF fiber can be classified as laser optimized (i.e., OM3), capable of supporting 10 Gb/s Ethernet communications up to 300 m (in theory). The fiber must meet 1 of 6 DMD mask templates, which specify the maximum modal dispersion (i.e., DMD) within radial regions of the core. If the fiber meets more stringent DMD requirements (to be specified by TIA), the fiber is characterized as OM4, capable of supporting a greater reach. Low modal dispersion as measured by DMD, is believed to translate to higher MMF performance.
Another useful metric that characterizes the bandwidth capability of MMF is Effective Modal bandwidth (EMB) expressed in units of Megahertz kilometer (MHz·km). The EMB is a calculated metric derived from the pulse waveforms obtained in the DMD measurement. The set of measured output waveforms are summed to model the resultant output signal waveform. Using a mathematical conversion to the frequency domain, the output and input waveforms are numerically divided to compute the bandwidth of the fiber. Applying weighting functions to simulate the radial optical power distribution of ten representative Vertical Cavity Surface Emitting Lasers (VCSELs), the minimum calculated EMB is determined (min EMBc). Using the min EMBc metric, the EMB of the fiber is calculated by a multiplication factor of 1.13 (i.e., EMB=1.13×min EMBc). To be characterized as OM3 and OM4, as specified in high speed Ethernet standards, the EMB values for these fibers must be at least 2000 MHz·km and 4700 MHz·km, respectively.
Because standard DMD and EMB utilize techniques that are based on time delay measurements using a monochromatic source (as specified in TIA-455-220-A), they are unable to discern between the two fibers shown in FIGS. 4A and 4B . The Blue and Brown fibers contained in the same optical cable are virtually identical by the metrics of DMD and EMB (See Table 1). Nonetheless they exhibit large differences in measured channel performance as benchmarked by analyzing the eye diagram, as shown in FIGS. 5A and 5B , and the Bit Error Rate Test (BERT) performance, as shown in FIG. 6 .
TABLE 1
Inner Mask
Outer Mask
DMD (5 to
DMD (0 to
EMB
Fiber
18 microns)
23 microns)
(EMB = 1.13 × EMBc)
Blue
0.122 ps/m
0.145 ps/m
4540
MHz*km
Brown
0.124 ps/m
0.132 ps/m
4540
*km
A relationship between BER system performance and DMD waveform shift has been discovered. The root cause is related to the left and right DMD temporal waveform shifts at large radial offsets, and the wavelength emission patterns of VCSELs. This difference can be observed in FIGS. 4A and 4B . VCSELs emit a single longitudinal mode coupled with multiple transverse modes resulting in a distribution of light with slightly different wavelengths over the area of emission. Each VCSEL mode has a defined polar emission pattern. This physical effect is referred to herein as a polar pattern having a radius-dependent wavelength. By determining if there are differences in pulse delays for each DMD waveform profile, or the polar pattern having a radius-dependent wavelength, both material dispersion and modal dispersion effects can be compensated for, further reducing modal dispersion from previous methods.
The impact of this emission pattern on the propagation of fiber modes is described below. The standard parabolic refractive index profile (based on an α value, as described by Equation 2) is currently designed to minimize the spread of all modes travelling through the fiber, with the assumption that all the modes have substantially the same wavelength (color). With reference to FIG. 7 , laser source emission patterns and wavelength distribution effects have been completely neglected.
However, VCSELs used in high-speed optical transceivers emit light with different wavelengths across the aperture of the device (modes). Longer wavelengths are emitted into smaller angles whereas short wavelengths are emitted into larger angles normal to the surface (polar emission pattern). With reference to FIG. 8 , this VCSEL spatial spectral distribution is preserved when coupled into fiber modes. The standard parabolic DMD waveform profile used today is valid only for the same wavelength of light across the aperture of the VCSEL, where all coupled fiber modes are believed to have the same center wavelength. The spatial distribution of optical wavelengths launched into the MMF requires a new preferred DMD waveform profile since the modes, with their radius-dependent wavelengths, are influenced by material dispersion effects. The effect of the radius-dependent emission pattern coupled with modal dispersion is illustrated in FIG. 9 . Lower order modes have longer wavelengths (“red”) and therefore travel faster than high order modes having shorter wavelengths (“blue”).
Based on data from our experimentation, fibers that exhibit a “left” shift in the radial pulse waveforms in the DMD profile (smaller values in ps/m) correspond to a lower-than-standard parabolic index of refraction in the outer region of the MMF core. This is observed at large radial offsets in the DMD waveform profile for the Blue fiber in FIG. 4A . The lower-order modes will not be affected by this shift in refractive index, as they do not travel through the outer region. Although higher-order modes are slowed down as a result of the wavelength-dependent index of refraction, as shown in FIG. 9 , since they travel in a region of lower than the so-called standard parabolic refractive index profile they in fact catch up with the “red” light (See FIG. 10 ).
For fibers having a “right” shift in large radial offset waveforms, the index of refraction is higher than the standard parabolic refractive index in the outer region of the core. This is seen in the DMD waveforms of the Brown fiber at high radial offsets, as shown in FIG. 4B . The lower-order modes will not be affected by this shift in refractive index, as they do not travel through that region. Higher order modes that were slowed down by the wavelength-dependent index of refraction, as shown in FIG. 9 , will travel through a region with higher than the standard parabolic index profile, and therefore slow down the “blue” light even further (See FIG. 11 ).
We have determined that the spectral distribution and polar emission patterns of VCSELs cannot be neglected and therefore, the current ideal DMD waveform profile is not optimal for minimum modal dispersion. Based on this discovery, by taking into account the differing wavelengths of the VCSELs modes, modal dispersion can be reduced, resulting in a modal wavelength compensated multimode fiber optic cable.
Minimizing modal dispersion can transform modal wavelength compensated MMF into a fiber that is primarily limited by its attenuation (plus the other penalties related to the VCSEL such as mode partition noise, modal noise, etc.). Using the IEEE 10 GBASE-SR link model, it is predicted that this improvement can potentially increase the maximum channel link reach from 125 m to potentially more than 200 m. By taking into consideration the spatial and spectral distributions of the light launched from VCSELs, an improved refractive index profile can be designed for an improved MMF that compensates for at least a portion of the wavelength dependency of the modes, allowing for modal dispersion to be further reduced from previous compensation methods.
While particular aspects of the present subject matter described herein have been shown and described, it will be apparent to those skilled in the art that, based upon the teachings herein, changes and modifications may be made without departing from the subject matter described herein and its broader aspects and, therefore, the appended claims are to encompass within their scope all such changes and modifications as are within the true spirit and scope of the subject matter described herein. Furthermore, it is to be understood that the invention is defined by the appended claims. Accordingly, the invention is not to be restricted except in light of the appended claims and their equivalents. | An improved multimode fiber optic cable is designed to compensate for the wavelength distribution and emission pattern of laser sources used in high-speed communication systems. The improved multimode fiber optic cable compensates for the wavelength dependent VCSEL polar emission pattern to reduce modal dispersion. Techniques for reducing the modal dispersion within the improved multimode fiber optic cable allow for improved Bit Error Rate (BER) system performance and/or to achieve greater reach in high bandwidth optical channel links are disclosed. Considerable efforts have been undertaken in the design and production of an improved multimode fiber optic cable to minimize modal dispersion, ignoring the effects of wavelength dependent polar emission patterns in lasers. Material dispersion effects have a significant impact on modal dispersion and by modifying a standard parabolic refractive index profile to compensate for material dispersion effects, overall modal dispersion can be reduced. | 6 |
BACKGROUND OF THE INVENTION
This invention is an improvement on the serving window of Leach and Miles U.S. Pat. No. 4,862,639, issued Sept. 5, 1989. The device of that patent is commercially successful and works well. However, it has at least one disadvantage in that a push/pull rod 32 of that device is located near one end of the counter, so that pressure on a bump bar 34 is most effective at one end of the bar.
One of the objects of this invention is to provide a serving window operable from the center of the span between window members.
Another object of this invention is to provide a serving window with an operating mechanism that is simple, rugged and dependable.
Other objects will be apparent to those skilled in the art in light of the following description and accompanying drawings.
SUMMARY OF THE INVENTION
In accordance with this invention, generally stated, a serving window has a pair of center opening swinging window members, each mounted on a vertical shaft projecting downwardly from its respective window member, a frame receiving the window members, the frame including a sill housing beneath the window members into which the shafts extend, and an operating mechanism in the housing for opening and closing the window members. The operating mechanism includes a crank arm secured to each of the shafts and a crank pin extending downwardly from each of the crank arms. An elongated operating bar extends between the crank pins, mounted intermediate its ends on pivot means and carrying channel means into which the crank pins extend. Operator means are provided substantially midway between the outer edges of the window members along the sill housing, for rocking the bar about the pivot means to rotate the crank arms between window opened and window closed positions. Preferably the operator means includes a shaft mounted to move substantially perpendicularly to the plane of the window members in their closed position, and a link pivoted to the shaft at one end and at another end to the operating bar. The top wall of the sill housing is stepped to form a ledge against which a lip along the bottom outer edge of the window members can abut.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings, FIG. 1 is a bottom plan view of one embodiment of operating mechanism of this invention;
FIG. 2 is a bottom plan view of the operating mechanism in a position in which window members are swung to their opened position;
FIG. 3 is a cut-away view in end elevation viewed from left to right in FIGS. 1 and 2;
FIG. 4 is a view in perspective of a serving window of this invention;
FIG. 5 is a fragmentary view in side elevation of a portion of the sill housing and window; and
FIG. 6 is a view of a second embodiment of operating mechanism.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the FIG. 1, reference numeral 1 indicates one illustrative embodiment of serving window of this invention. The serving window 1 includes swinging window members 2 and 3, mounted in a frame 4. The frame 4 includes a sill housing 5.
The sill housing 5 is essentially an open bottomed box, with a top wall 11, side walls 15, front or inner wall 16 and rear or outer wall 17. The top wall 11 is, in this illustrative embodiment, provided with a step 12, which forms a ledge 13 against which a lip 7 along each of the swinging window members 2 and 3 abuts. It also provides, on the inside of the housing 5, head room between the under side of the top wall 11 and a mounting plate 18. The plate 18, which can be made of heavy aluminum, is mounted by means of screws 20, extending through the top wall 11 and into interior frame members, not here shown, serving the double purpose of mounting the plate 18 and joining the jamb posts of the frame 4 to the sill housing. Depending upon the construction of the jamb posts, the mounting plate 18 may be bolted to them. As can be seen from FIG. 3, the step in the top wall provides head space between a portion of the plate and the undersurface of the sill top. An axle bolt 22, with a head 23 and a shank 24, extends through a hole in the mounting plate 18, with the head 23 in the head space, and is held, in this embodiment, with a lock nut run up tightly against the inside surface of the mounting plate.
Each of the window members 2 and 3 has a pivot pin 27 extending downwardly near its outboard edge, through holes in the top 11 and mounting plate 18. The pins 27 carry at their lower ends cranks 29 from the free end of which crank pins 33 depend.
An operating bar 35, in this embodiment, in the form of a steel plate, is pivotally mounted on the axle bolt 22. The operating bar 35 is rectangular in plan, as illustrated in FIGS. 1 and 2. The bar is pivoted at a point that is asymmetrical with respect to both the longitudinal and transverse center lines of the bar. The bar 35 has channel members into which the crank pins 33 extend. In this embodiment, the channel members take the form of arcuate slots 39 and 40 through the bar, through which the crank pins extend. The slots 39 and 40 are oppositely oriented with respect to the longitudinal center line of the bar 35, as seen clearly in FIGS. 1 and 2.
A guide block 42 is mounted on the lower surface of the operating bar 35 by means of a retainer bolt 43 which is mounted at its upper end in the bar 35 in such a way as to permit movement of the guide block 42 about the retainer bolt. The guide block 42 has a passage running transversely through it, the axis of which is substantially along the transverse center line of the operating bar 35, which is equidistance from the outer edges of the window members 2 and 3, and also from the side walls 15 of the sill housing
An operator shaft 45 extends at its distal end with respect to the front wall 16, through the passage in the guide block 42, and at its proximal end, through a bearing block 47 and beyond the front wall 16. The bearing block 47 is mounted on the front wall 16 and is provided with a passage through which the operator shaft 45 passes slidably but closely as compared with the passage through the guide block 42 which is sufficiently oversized with respect to the diameter of the shaft 45 to permit relative movement of the guide block 42 and the shaft 45, through a very small arc. The operator shaft 45 carries at its outer end, a bump roll 49, by which a person can move the operator shaft 45 from the position shown in FIG. 1 to the position shown in FIG. 2.
An operating lever 51 is pivoted at 53, at one end, to the operating shaft 45, and at its other end, on a pivot 55, to the bar 35.
A return mechanism 60, which can take the form of a cylinder and piston, either provided with an internal spring or a pneumatic actuator, is pivotally mounted on a mounting bracket 61 attached to the sill housing at one end, and to the operating bar 35 by a pivot pin 62, at its other end. When the operating shaft is not pushed in against the bias of the spring, the spring keeps the operating bar in the position shown in FIG. 1, in which the window members 2 and 3 are closed.
Merely by way of illustration, in a serving window in which the sill housing 5 is rectangular in plan, the distance between the side walls 15 being approximately twenty-four inches and the distance between the front wall 16 and the rear wall 17 approximately twenty inches, the distance from the rear wall 17 to the step 12 being five inches, and from the ledge 13 to the front wall 16, about fifteen inches, the jamb members of the frame being approximately three quarters by four inches, and the step ledge being approximately a quarter inch high, the mounting plate 18, made of quarter inch aluminum, can be approximately four inches wide and as long as the distance between the inner surfaces of the side walls 15 permits. The operating bar 35 can be a steel plate three sixteenth inch thick, two and a half inches wide and twenty-one and a half inches long. The distance of the center of the pin 22 from the rear edge of the bar can be approximately one and one sixteenth inches. The passage through the operating bar is of a size to admit a bushed axle shaft 24 three eighths inch in diameter, and the distance to the center of the passage from the right edge of the operating bar as viewed in FIGS. 1 and 2 is on the order of ten and five sixteenth inches.
The guide block 42 can be a block of nylon two inches long, one inch high, and a half inch thick. The passage through the guide block through which the operator shaft 45, when the operator shaft 45 is a cylindrical rod half an inch in diameter, can be eighteen thirty seconds, while the diameter of the passage through the bearing block 47 is preferably on the order of thirty-three sixty-fourths. The bearing block 47 can also be of nylon, and is preferably somewhat thicker, as for example, one inch, to provide more bearing surface. The retainer bolt 43 can be a 632 machine screw two inches long, with a nut held in place by Locktite or the like to permit the block 42 to move about the retainer bolt. The movement need be slight, because the travel of the operating bar 35 at its outer ends is only in the neighborhood of two to two and one half inches. The slot 39 in this illustrative embodiment can be five eighths of an inch wide and an inch and three quarters long, and the slot 40, also five eighths of an inch wide, two and one eighths inches long. The configuration and position of the of the slots will depend upon the length of the crank arms 29. The crank pin 33 can be quarter inch/20 stud, surrounded by a nylon bearing sleeve, retained by a locknut and washer that can also serve to retain the operating bar.
The operating lever 51 can be made of one quarter by one half inch steel, and can take the form of an angle or channel iron to add rigidity to the lever, if desired.
As will be apparent from FIGS. 1 and 2, when the bump roll 49 is pushed toward the wall 16 of the sill housing, the lever 51 rocks the operating bar about the pivot 22, causing the crank pins 33 to engage a concave surface of the slot in which it rides, rotating the crank arm from which the pin extends, hence the window member pivot pin, which is secured to the window member to rotate the window members to the position shown in FIG. 2. When pressure on the bump roll 49 is released, the spring mechanism 60 restores the assembly to the condition shown in FIG. 1, the crank pins engaging the convex surface of the slot to rotate the crank arms to their initial position.
Referring now to FIG. 6 for a still further simplified version of window means operating mechanism, which still can be operated from the center of the window sill, an operator shaft 145 is journaled in suitable bearings for linear motion. The shaft projects from the sill housing, and is provided with a bump roll, just as the operator of the first embodiment is. In this embodiment, two push rod levers 151 and 152 are provided, both pivoted at one end to the operator shaft 145, and at their other ends, to crank pins 133 of cranks 129 secured to window member pivot pins 127. In this embodiment, a return spring mechanism 160 is connected at one end to a mounting bracket 161 carried by the sill housing, and at its other end, to the operator shaft 145 itself.
The operation of the mechanism of this embodiment will be self-evident from the description of the first embodiment.
Numerous variations in the construction of the window and its operating mechanism, within the scope of the appended claims, will occur to those skilled in the art in the light of the foregoing disclosure.
Merely by way of example, the channel members carried by the operating bar can take the form of nylon or other plastic bosses, either set into openings in the plate or surface mounted. The operating shaft can be made telescopic between the bump roll and lever pivot point, and equipped with a compression spring to absorb shock and preclude damage to the mechanism. These are merely illustrative. | In a serving window having a pair of center-opening swinging window members of the type illustrated and described in U.S. Pat. No. 4,862,639, a crank pin, extending downwardly from the crank arm of each window member, extends into a channel carried by an elongated bar extending between the crank pins. The bar is pivoted asymmetrically and is rocked about its pivot point by an operator shaft positioned substantially midway between the window members. A link is pivoted at one end to the operator shaft and at its other end, to the bar adjacent one end thereof. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a device affixing a weaving reed, hereafter reed, to the batten beam of a weaving machine, the reed comprising an upper profiled bar, in particular an upper U-channel, a lower profiled bar, in particular a lower U-channel, to be affixed to the batten beam, and reed dents mounted in-between.
2. Description of the Related Art
It is known to affix the lower U-channel profiled bar of a reed by a clamp, for instance by a key, to a batten beam. However it has been observed that at high weaving rates, i.e. of the order of 1,000 or more filling insertions per minute, that the reed dents may break in the vicinity of the lower U-channel profiled bar.
It is known to reinforce one or both ends of the reed with solid steel bars which are mounted between the upper and lower U-channels in relation to the reed dents and parallel to them. Such a reinforcing bar may be straight or be bent several times. When such a reinforcing bar is situated on the filling insertion side of the reed, difficulties are encountered in locating the main air jet nozzles and a cutter for the fillings, which should be located directly at the fabric selvage or at the reed. If such a reinforcing bar is mounted on the opposite reed side, then it will hamper the installation of a filling detector or of a filling stretcher, which also should be mounted directly at the fabric's side selvage or at the reed. In many cases this leads to a fabric having relatively wide waste edges. Moreover there may be streaks at the fabric edge in the zone of a solid-steel reinforcing bar. Regardless, at high weaving rates, such a reinforcing bar may fail to prevent the reed dents from breaking at the lower U-channel.
SUMMARY OF THE INVENTION
The objective of the invention is to create a device of the initially cited kind to substantially reduce the danger of the reed dents breaking.
This problem is solved in that the upper profiled bar of the reed is secured, at least in its end region, to the batten beam by a connecting brace element running substantially in the reed's longitudinal direction, against displacements in said longitudinal direction relative to the beam.
The invention offers the feature that the reed, in particular the upper profiled bar, and the reed dents shall not oscillate in the longitudinal direction of the reed. As a result the danger of reed dent rupture in the vicinity of the lower profiled bar already is substantially reduced.
In a further embodiment of the invention, the connection element shall be flexible transversely of the reed. Consequently the connection brace element will not restrict the reed dent deformation transversely to the reed's longitudinal direction at beat up against the fabric's edge, and thereby the reed dents are able to deform uniformly at beatup. This feature generally precludes fabric streaks. Also the danger of reed dent rupture in the vicinity of the lower profiled bar caused by beatup stresses is substantially reduced.
In a preferred embodiment, the connecting brace element is a metal blade affixed both to the upper profiled bar of the reed and at a distance from the end of the reed to the batten beam. In an advantageous design, the blade is made of steel and its thickness transversely to the reed is about 2 mm, its height parallel to the reed is about 15 mm and its length is approximately 100 to 200 mm. Such a blade will not bend at the stresses encountered, and longitudinal reed displacements are substantially prevented. Transverse displacements however are allowed and as a result the danger of forming streaks in the fabric is reduced.
In a further embodiment of the invention, a support holding the connecting element brace is mounted on the batten beam in a direction along an extension of the reed. As a result the connecting element is connected in simple manner to the batten beam while spaced from the reed. As regards an airjet loom, at least one main jet nozzle shall be mounted appropriately on this support. When the connecting element is mounted opposite the insertion side, then appropriately a filling detector and/or a filling stretcher shall be mounted on the said support. As a result, this support also can be used to mount operationally required components and the total number of additional parts is very low.
Further features and advantages of the invention will be evident from the description of the embodiments shown in the drawing and in the sub-claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective of a device of the invention to affix a reed to a batten beam,
FIG. 2 is a section along the plane II of FIG. 1,
FIG. 3 is a section along plane III of FIG. 1,
FIG. 4 is a section along plane IV of FIG. 1, and
FIG. 5 is a perspective of another embodiment of a device of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The reed 1 shown in FIGS. 1 and 2 is fitted with a plurality of sequentially mounted reed dents 2 . A U-shaped recess is present approximately centrally in the reed dents 2 which together constitute a guide duct 3 for a filling. The reed dents 2 are affixed in a cross-sectionally profiled upper and a lower bar, namely in an upper U-channel 4 and in a lower U-channel 5 . In both the upper U-channel 4 and in the lower U-channel 5 , the reed dents 2 are kept apart from each other a predetermined distance by so-called connecting spirals 7 , 8 . Together with one connecting spiral 7 and 8 and retention bars 9 and 10 , the reed dents 2 are bonded into the upper and lower U-channels 4 and 5 respectively. The lower U-channel 5 is affixed by a key 11 and screws 13 to a batten beam 12 . The batten beam 12 is affixed in known manner by batten arms (not shown) to a batten shaft (not shown) extending parallel to the batten beam 12 .
In addition, an elongated connecting blade or brace element 14 is mounted on the reed 1 and extends substantially in the longitudinal direction A of this reed 1 and prevents said reed from moving in said direction A relative to beam 12 . In this embodiment the connecting blade 14 is mounted on the filling insertion side of the reed 1 . The connecting blade 14 is made of steel for instance and its thickness in the transverse direction B is roughly 2 mm. Its height is about 15 mm. The connecting blade's length is about 100 to 200 mm.
The end 15 of the connecting blade 14 is connected to the batten beam 12 and is spaced from the reed 1 . A fastener 17 is mounted on the end 15 and is affixed by a screw 16 to a support 18 which in turn is affixed to the batten beam 12 . This connection is carried out in relation to the connection of the lower U-channel 5 , that is using a key 19 and screws 20 , as shown in FIGS. 1 and 3.
The support 18 is formed in the shape of a bent metal plate which, in the case of an airjet loom, and as shown in FIGS. 1 and 3, also supports one or more main jet nozzles 21 , 22 . For that purpose a retention device 23 of the main airjet nozzles 21 , 22 is fastened by screws 24 to the support 18 . The ends of the jet tubes 25 , 26 of the main airjet nozzles 21 , 22 are also fastened by a further retention element or means 27 and a screw 28 to the support 18 .
The end 29 of the connection blade 14 which is directed to the reed 1 is mounted to the upper U-channel 4 of said reed. For that purpose a strip 30 is inserted into that space between the legs of the U-channel which extends away from the reed dents 2 . The width of this strip 30 is about the same as the width of the upper zones of the dents 2 of the reed 1 which are bonded into the zone subtended between the legs of the upper U-channel 4 . Accordingly the strip 30 can be housed in said leg space of the upper U-channel 4 similar to the reed dents 2 . The strip 30 adjoins the first dent 2 A of the reed 1 and the end of the connecting spiral 7 . The retention bars 9 run over a given length beyond the first reed dent 2 A and the end of the connecting spiral 7 . Together with the retention bars 9 , the strip 30 is bonded to the upper U-channel 4 . Moreover the retention bars 9 may be welded onto the strip 30 . A strong connection is required between the strip 30 and the upper U-channel 4 because it must absorb comparatively high stresses. The shown embodiment also includes a retention strip 32 which is bonded to the back side of the upper U-channel 4 of the reed 1 . The connecting blade 14 is mounted between the strip 30 and the retention strip 32 and is affixed by a screw 31 . Preferably the strip 30 is made of steel because such a selection is advantageous when affixing the connecting blade 14 using a screw 31 . The thickness of the connecting blade 14 of this embodiment substantially corresponds to the thickness of the rear leg 33 (FIG. 2) of the upper U-channel 4 . In this case, after the screw 31 has been tightened, the strip 30 and the retention strip 32 remain substantially mutually parallel. This design is especially appropriate for reeds wherein the upper U-channel 4 is made of aluminum or another relatively lightweight metal which per se would offer only modest mechanical strength.
In one embodiment variation, the connecting blade 14 is directly affixed by a screw to the upper U-channel 4 of the reed 1 . This design is advantageous for instance when the upper U-channel 4 of the reed 1 is made of steel or another metal of comparatively high mechanical strength.
FIG. 5 shows an embodiment which again offers the above described advantages, but wherein a connecting blade 34 is mounted on the opposite side of the reed 1 , that is, at the side which is opposite the filling insertion side. The connecting blade 34 is connected in the manner of the embodiment of FIG. 1 by one end 39 to the upper U-channel 4 of the reed 1 and by its end 40 to a support 35 . A filling detector 36 and/or a filling stretcher 37 is/are mounted on the support 35 which again is a bent metal plate and therefore are mounted directly next to the reed 1 . The filling detector 36 and the stretcher 37 each are affixed by a screw 41 and 42 to the support 35 .
In a further embodiment not shown, a connecting blade 14 is mounted at the filling insertion side of the reed 1 corresponding to FIG. 1 as well as a connecting blade 34 at the opposite side corresponding to FIG. 5 .
By introducing one or both elongated connecting blades 14 , 34 , the reed 1 and in particular the upper U-channel 4 and the reed dents 2 shall be prevented from oscillating in the longitudinal direction A during weaving operation. The connecting blades 14 and/or 34 absorb both tensile and compressive forces, which prevent a displacement of the upper U-channel 4 toward the filling insertion side and in the opposite direction. The connecting blades 14 and 34 are dimensioned in such manner that they shall be strong enough not to bend when subjected to compression. Calculation shows that a connecting blade 14 or 34 about 2 mm thick and about 15 mm high is adequately resistant to bending when forces that arise at a weaving rate of 1,200 filling insertions a minute and with as many corresponding beatups.
The elongated connecting blades 14 and/or 34 at worst will slightly degrade the displacement in the transverse direction B of the end zone 6 of the reed 1 in the vicinity of the main airjet nozzles 21 , 22 and/or of the end zone 38 of the reed 1 in the vicinity of the filling detector 36 or the stretcher 37 . The displaceability of the reed 1 in these zones 6 and 38 is not restricted with respect to the middle zone. Such a feature is attained by the connecting blades 14 and/or 34 being comparatively long and consequently will not unduly oppose bending in the transverse direction B. As a result, any differential in the displaceability of the reed 1 in the transverse direction B is prevented that produces streaks or other irregularities in the vicinity of the selvages. On the other hand, because displacements and oscillations of the upper U-channel 4 are substantially suppressed in the longitudinal direction A, the dents 2 of the reed 1 are stressed less in the vicinity of the lower U-channel 5 , and consequently the danger that the reed dents 2 should break in this region is considerably reduced.
The elongated connecting blade or brace elements 14 or 34 need not necessarily be in the shape of a blade or the like. Illustratively they may be in the form of round or polygonal bars of arbitrary cross-sections, which however should be designed in such a way that while substantially suppressing a displacement of the reed in the longitudinal direction A, they shall allow the displacement of the reed 1 in the transverse direction B. If called for, the connecting elements also may be wires, especially steel wires, or also plastic cords.
The invention is not restricted to the above described and illustrated embodiments. The scope of the invention is defined by the attached claims and allows changes and/or other combinations. | An elongated connecting blade or bracing element ( 14 ) is used to fix a reed ( 1 ) to a batten beam ( 12 ). The blade runs substantially in the longitudinal direction (A) of the reed ( 1 ) and is connected to the upper profiled bar ( 4 ) of the reed ( 1 ) and to the batten beam ( 12 ) while being spaced away from the reed ( 1 ), in order to reduce a displacement of the reed ( 1 ) in the longitudinal direction (A). | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation application of U.S. patent application Ser. No. 14/107,321 filed on Dec. 16, 2013, which is a continuation application of U.S. patent application Ser. No. 13/772,962 filed on Feb. 21, 2013. This application claims priority to Japanese Patent Application No. 2012-047694 filed on Mar. 5, 2012. The entire disclosures of U.S. patent application Ser. Nos. 14/107,321 and 13/772,962 and Japanese Patent Application No. 2012-047694 are hereby incorporated herein by reference.
BACKGROUND
[0002] 1. Technical Field
[0003] The present invention relates to a mist collection device that collects a mist of liquid generated by ejecting liquid from a nozzle, and a liquid ejection device.
[0004] 2. Related Art
[0005] A printer in which a mist is sucked into a recovery device is known (see Japanese Laid-Open Patent Publication No. 2011-62982). In Japanese Laid-Open Patent Publication No. 2011-62982, the mist sucked into the recovery device is collected in a filter.
SUMMARY
[0006] In the above mentioned publication, however, ink that has turned into liquid droplets in the recovery device adheres to the filter or remains in the recovery device, which causes deterioration of the suction force into the recovery device.
[0007] The present invention has been made to address the above-described circumstances, and an object of the present invention is to provide a technique for preventing liquid that has turned into liquid droplets from impeding collection of a mist.
[0008] A liquid ejection device according to one embodiment includes an ejection head, a suction section, a space section, a collection part, an outlet section and a suction device. The ejection head is configured and arranged to eject liquid from a plurality of nozzles onto a recording medium. The suction section has a slit shaped opening. The space section is in communication with the suction section and has an internal volume greater than an internal volume of the suction section. The collection part is configured and arranged to collect the mist generated by ejecting the liquid by separating the mist from air suctioned by the suction section. The outlet section has a first opening and a second opening, the first opening is in communication with the space section and the second opening is in communication with the collection part. The suction device is configured and arranged to generate an air flow flowing from the suction section to the collection part. Opening area of the slit shaped opening is greater than opening area of the first opening.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Referring now to the attached drawings which form a part of this original disclosure:
[0010] FIG. 1 is a block diagram of a printer.
[0011] FIG. 2 is a perspective view of a suction container.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0012] Hereinafter, embodiments of the present invention will be explained in the following order: (1) Configuration of Printer; (2) Configuration of Mist Collection Device; and (3) Modified Embodiment.
(1) Configuration of Printer
[0013] FIG. 1 is a block diagram showing a configuration of a printer 1 as a liquid ejection device including a mist collection device according to an embodiment of the present invention. The printer 1 has a feed section 10 , a print section 11 , a recovery section 12 , and an ejection head 13 . The feed section 10 has a feed reel 10 a and a tension adjustment section 10 b. A roll of paper M (thick broken line) is rolled around a roll core of the feed reel 10 a, and the roll of paper M is reeled out by rotating the feed reel 10 a around a central axis of the roll core. The tension adjustment section 10 b has a roller biased to exert prescribed tension on the roll of paper M between the feed reel 10 a and the print section 11 .
[0014] The print section 11 has a drum 11 a (one example of a support part), a feed-in roller 11 b, and a feed-out roller 11 c. The drum 11 a is formed to have a cylindrical shape or an elliptic cylindrical shape, and rotates around a central axis X. The feed-in roller 11 b is a roller for introducing a roll of paper M fed from the feed section 10 to the drum 11 a in a tangential direction of the side surface of the drum 11 a. The feed-out roller 11 c is a roller for introducing out a roll of paper M retained on the side surface of the drum 11 a in the tangential direction of the side surface of the drum 11 a. When the drum 11 a rotates counterclockwise with respect to the drawing, a roll of paper M can be retained on the side surface of the drum 11 a, and a roll of paper M can be delivered from the feed section 10 to the recovery section 12 .
[0015] The recovery section 12 has a recovery reel 12 a and a tension adjustment section 12 b . A roll of paper M is rolled around a roll core of the recovery reel 12 a, and the roll of paper M is reeled in by rotating the recovery reel 12 a around the central axis of the roll core. The tension adjustment section 12 b has a roller biased to exert prescribed tension on the roll of paper M between the recovery reel 12 a and the print section 11 .
[0016] The ejection head 13 is provided for each kind of ink as liquid. In the present embodiment, the ejection head 13 is provided for each of C (cyan), M (magenta), Y (yellow), and K (black). Each of the ejection heads 13 has a similar configuration, and is disposed to have rotation symmetry with respect to the central axis X of the drum 11 a. Each of the ejection heads 13 has a nozzle surface 13 a to face a roll of paper M retained on the side surface of the drum 11 a. A plurality of nozzles are arranged in a surface of the nozzle surface 13 a. Ink is ejected from the plurality of nozzles toward a roll of paper M retained on the side surface of the drum 11 a. In each of the four ejection heads 13 , a direction of ejecting ink is a direction toward the central axis X of the drum 11 a. The ejecting directions θ with respect to the central axis X in the ejection heads 13 are different from each other by 30 degrees.
(2) Configuration of Mist Collection Device
[0017] The printer 1 as a configuration of the mist collection device for collecting a mist of ink has a suction container 22 , a collection container 23 , and a suction fan 24 . The suction container 22 is provided corresponding to each of the ejection heads 13 , and is disposed adjacent to each of the ejection heads 13 . The suction container 22 is disposed adjacent to a vertical wall surface 13 b (wall surface perpendicular to the nozzle surface 13 a ) of each of the ejection heads 13 from below. Specifically, the suction container 22 is adjacent to the vertical wall surface 13 b of each of the ejection heads 13 (C, M, Y and K) from the clockwise direction with respect to the drawing. More specifically, the suction container 22 is adjacent to the vertical wall surface 13 b of each of the ejection heads 13 from the downstream of a direction of feeding a roll of paper M.
[0018] Air inside the collection container 23 is sucked by driving the suction fan 24 as the suction device. Each of the plurality of the suction containers 22 is connected to the single collection container 23 , and air inside each of the suction containers 22 is collected into the collection container 23 . A collection wall 23 a (broken like) is formed inside the collection container 23 . When a mist of ink contained in air inside the collection container 23 collides with the collection wall 23 a, the mist of ink is turned into liquid droplets. A reservoir section 23 b is provided at a lower part of the collection container 23 in the vertical direction. Ink that has been turned into liquid droplets flows down to the reservoir section 23 b, and is stored in the reservoir section 23 b. For example, the reservoir section 23 b may be removable from the main body of the collection container 23 , and the reservoir section 23 b can be replaced or cleaned by removing the reservoir section 23 b from the collection container 23 .
[0019] FIG. 2 is a perspective view of the suction container 22 provided corresponding to the ejection head 13 (Y) for Y ink. The suction container 22 has a suction section 22 a, a hollow member 22 b, and an outlet section 22 c. The hollow member 22 b corresponds to the tube section. In the present embodiment, two lines of nozzles (thick broken line) are provided on the nozzle surface 13 a of each of the ejection heads 13 , and the arrangement direction of the nozzles in the lines of nozzles is parallel to the central axis X of the drum 11 a. Here, the length of the lines of nozzles is represented by A. The suction section 22 a has a hollow shape in which the cross-section cut in parallel with the nozzle surface 13 a has a prescribed rectangle shape. The length B of the internal space of the suction section 22 a in the arrangement direction of the nozzles is greater than the length A of the lines of nozzles. The length C of the internal space of the suction section 22 a in a direction perpendicular to the arrangement direction of the nozzles is smaller than the length B in the arrangement direction of the nozzles. Therefore, the internal space of the suction section 22 a has an elongated shape that is long in the arrangement direction of the nozzles. An elongated opening that is long in the arrangement direction of the nozzles is formed at an upper end and a lower end of the suction section 22 a, respectively. The opening at the lower end forms a suction port 22 a 1 . In the internal space of the suction section 22 a, air flows from the suction port 22 a 1 at the lower end toward the upper end. The direction of an air flow in the internal space of the suction section 22 a is a direction opposite to the direction of ejecting ink in the ejection head 13 . The air flow is schematically shown by a thick arrow.
[0020] The hollow member 22 b is formed to have a cylindrical shape whose central axis Y is parallel to the arrangement direction of the nozzles. The upper end of the suction section 22 a and the hollow member 22 b are connected such that the direction of the air flow in the internal space of the suction section 22 a coincides with the tangential direction of the side surface of the hollow member 22 b. Consequently, air is introduced to the tangential direction of the side surface of the hollow member 22 b through the opening at the upper end of the suction section 22 a.
[0021] The hollow member 22 b is constructed by a main body section 22 b 1 , and two lid sections 22 b 2 , 22 b 3 . The main body section 22 b 1 , and the lid sections 22 b 2 , 22 b 3 are separate members, and are attached to each other when the printer 1 is assembled. The main body section 22 b 1 is an open tube in which the both ends in the longitudinal direction are opened. Each of the lid sections 22 b 2 , 22 b 3 is formed to have a circular shape that is the substantially same shape as the cross-section of the hollow member 22 b perpendicular to the longitudinal direction. An outer peripheral portion “e” is raised in the longitudinal direction of the hollow member 22 b by a prescribed height. The inner diameters of the outer peripheral portions “e” of the lid sections 22 b 2 , 22 b 3 are formed to have the same magnitude as the outer diameter of the main body section 22 b 1 . The both ends of the main body section 22 b 1 in the longitudinal direction are fitted into the insides of the outer peripheral portions “e” of the lid sections 22 b 2 , 22 b 3 , and the lid sections 22 b 2 , 22 b 3 are rotatably attached to the main body section 22 b 1 . A discharge port 22 d having a circular shape is formed in the lid section 22 b 2 so as to internally contact the outer peripheral portion “e”. When the lid section 22 b 2 rotates with respect to the main body section 22 b 1 , the discharge port 22 d moves in a circumferential direction along the end surface of the main body section 22 b 1 in the longitudinal direction.
[0022] As shown in FIG. 1 , the ink ejecting direction θ with respect to the central axis X of the drum 11 a is different from each other by 30 degrees, and the arrangement position of the hollow member 22 b with respect to the vertical wall surface 13 b in parallel with the ejecting direction θ is different for each of the ejection heads 13 . However, irrespective of the angle of the vertical wall surface 13 b, the lid section 22 b 2 is fixed to the main body section 22 b 1 in a state where the lid section 22 b 2 rotates such that the discharge port 22 d is located at the lower end of the hollow member 22 b in the vertical direction. The main body section 22 b 1 and the lid sections 22 b 2 , 22 b 3 can be fixed by an adhesive, welding, screwing or the like. Further, a packing or the like may be interposed between the main body section 22 b 1 and the lid sections 22 b 2 , 22 b 3 so as to achieve air tightness. Although a material for the main body section 22 b 1 and the lid sections 22 b 2 , 22 b 3 is not limited to a specific one, a light shielding material is preferable in a case where ink is light curing ink.
[0023] In FIG. 2 , the discharge port 22 d (Y) of the hollow member 22 b provided corresponding to the ejection head 13 (Y) for Y ink is shown by a broken line, and the discharge port 22 d (K) of the hollow member 22 b provided corresponding to the ejection head 13 (K) for C ink is shown by a two-dot chain line. As shown in FIG. 2 , when comparing the discharge port 22 d (Y) and the discharge port 22 d (K) provided in the ejection head 13 (Y) and the ejection head 13 (K) whose ejecting directions θ are different from each other by 30 degrees, the arrangement positions of the discharge port 22 d (Y) and the discharge port 22 d (K) viewed from the central axis Y of the hollow member 22 b are different from each other by 30 degrees.
[0024] The outlet section 22 c is a tube having a circular cross-section. As shown in FIG. 1 , the outlet section 22 c connects each of the suction containers 22 (each of the discharge ports 22 d ) and the collection container 23 . In the present embodiment, the outlet section 22 c has four branches that connect to the discharge ports 22 d of the suction containers 22 , respectively. The four branches are merged into one, and then connected with the collection container 23 .
[0025] In the configuration of the present embodiment described above, air containing a mist of liquid generated by ejecting ink from the plurality of nozzles can be sucked from the suction port 22 a 1 to the suction section 22 a. Air containing a mist sucked to the suction section 22 a is introduced to the hollow member 22 b, and flows through the hollow member 22 b. When air containing a mist flows through the hollow member 22 b and collides with the wall surface of the hollow member 22 b, the mist turns into liquid droplets, and ink that has turned into liquid droplets flows down toward the lower part in the vertical direction due to the gravity. Since the discharge port 22 d is formed at the lower end of the hollow member 22 b in the vertical direction, ink that flows down toward the lower part in the vertical direction within the hollow member 22 b can be introduced from the discharge port 22 d to the outlet section 22 c together with air containing a mist. Since ink introduced to the outlet section 22 c together with air containing a mist is introduced to the collection container 23 , the collection container 23 can collect ink that has turned into liquid droplets in the hollow member 22 b together with air containing a mist. Accordingly, it is possible to prevent collection of a mist from being obstructed by ink that has turned into liquid droplets until reaching the collection container 23 .
[0026] The discharge port 22 d for discharging ink that has turned into liquid droplets from the hollow member 22 b is formed at the lower end in the vertical direction in the lid section 22 b 2 for closing the hollow member 22 b from an end in the longitudinal direction. With this, the outlet section 22 c that connects the collection container 23 and the hollow member 22 b can be disposed around the outside of the hollow member 22 b in the longitudinal direction. Therefore, even in a case where the plurality of ejection heads 13 are arranged such that the arrangement directions of the nozzles are in parallel with respect to each other, the outlet section 22 c can be disposed around the outside of the hollow member 22 b in the longitudinal direction (the arrangement directions of the nozzles), and thus the outlet section 22 c can be formed so as not to interfere with the ejections heads 13 . If the discharge port 22 d is formed in the lid section 22 b 2 at the end of the hollow member 22 b in the longitudinal direction, the suction force from the discharge port 22 d possibly becomes non-uniform in the longitudinal direction of the hollow member 22 b. However, it is possible to prevent the suction force from becoming non-uniform in the longitudinal direction by increasing the volume of the hollow member 22 b.
[0027] Further, the lid section 22 b 2 is formed such that the discharge port 22 d moves by rotation along an end surface of the hollow member 22 b in the longitudinal direction. With this, even when the attachment angle of the hollow member 22 b with respect to the printer 1 varies, the discharge port 22 d can be located at the lower end of the hollow member 22 b in the vertical direction. Accordingly, there is no need to prepare the lid section 22 b 2 for each attachment angle of the hollow member 22 b with respect to the printer 1 . In the present embodiment, although the attachment angle of the hollow member 22 b with respect to the printer 1 is different for each kind of ink, the components (the main body section 22 b 1 , and the lid sections 22 b 2 , 22 b 3 ) of the hollow member 22 b can be made in common irrespective of the kind of ink.
[0028] Further, the suction section 22 a and the hollow member 22 b are connected with each other such that the air flow direction in the suction section 22 a is a tangential direction of a cross-section perpendicular to the longitudinal direction of the hollow member 22 b, that is a side surface of the hollow member 22 b. With this, air from the suction section 22 a can be introduced along the side surface of the hollow member 22 b, and the air flow direction can be changed gradually along the wall surface of the hollow member 22 b. Therefore, pressure loss inside the hollow member 22 b can be controlled. When air flows along the side surface of the hollow member 22 b, a mist easily turns into liquid droplets on the side surface of the hollow member 22 b. In such a case, however, liquid droplets generated on the side surface can be collected in the collection container 23 through the discharge port 22 d.
[0029] Since the hollow member 22 b has a cylindrical shape, ink that has turned into liquid droplets is caused to smoothly flow down toward the lower end in the vertical direction along the side surface of the hollow member 22 b. Also, since the hollow member 22 b has a cylindrical shape, the rotation angle of the lid section 22 b 2 with respect to the main body section 22 b 1 can be adjusted continuously, and the main body section 22 b 1 and the lid section 22 b 2 can be used for various kinds of printers 1 .
(3) Modified Embodiment
[0030] In the above-described embodiment, the hollow member 22 b has a cylindrical shape. However, the hollow member 22 b may have an equilateral polygonal prism shape. In order to cause ink that has turned into liquid droplets to smoothly flow down toward the lower end in the vertical direction along the side surface of the hollow member 22 b, it is preferable that the internal angle of the cross-section of the hollow member 22 b is made as large as possible. Specifically, when the hollow member 22 b has an equilateral polygonal prism shape, it is preferable that the shape is an equilateral polygonal prism having five sides or more so as to make the internal angle obtuse. Also, the discharge port 22 d may be disposed at both ends of the hollow member 22 b in the longitudinal direction.
[0031] In the above-described embodiment, the printer 1 ejects ink droplets. However, it is also possible to eject liquid other than ink droplets. Further, liquid may be ejected by applying pressure due to a mechanical change of a piezoelectric element, or may be ejected by applying pressure due to generation of air bubbles. Further, a medium to be recorded is not limited to printing paper, and may be cloth or a film made of resin, or the like. A medium to be recorded is not limited to one that is retained on the side surface of the drum, and may be retained on a platen having a flat shape. Further, the ejection heads do not need to be plural, and a single or a plurality of suction containers may be provided with respect to a single ejection head.
GENERAL INTERPRETATION OF TERMS
[0032] In understanding the scope of the present invention, the term “comprising” and its derivatives, as used herein, are intended to be open ended terms that specify the presence of the stated features, elements, components, groups, integers, and/or steps, but do not exclude the presence of other unstated features, elements, components, groups, integers and/or steps. The foregoing also applies to words having similar meanings such as the terms, “including”, “having” and their derivatives. Also, the terms “part,” “section,” “portion,” “member” or “element” when used in the singular can have the dual meaning of a single part or a plurality of parts. Finally, terms of degree such as “substantially”, “about” and “approximately” as used herein mean a reasonable amount of deviation of the modified term such that the end result is not significantly changed. For example, these terms can be construed as including a deviation of at least ±5% of the modified term if this deviation would not negate the meaning of the word it modifies.
[0033] While only selected embodiments have been chosen to illustrate the present invention, it will be apparent to those skilled in the art from this disclosure that various changes and modifications can be made herein without departing from the scope of the invention as defined in the appended claims. Furthermore, the foregoing descriptions of the embodiments according to the present invention are provided for illustration only, and not for the purpose of limiting the invention as defined by the appended claims and their equivalents. | A liquid ejection device includes an ejection head, a suction section, a space section, a collection part, an outlet section and a suction device. The suction section has a slit shaped opening. The space section is in communication with the suction section and has an internal volume greater than an internal volume of the suction section. The collection part is configured to collect the mist generated by ejecting the liquid by separating the mist from air suctioned by the suction section. The outlet section has a first opening and a second opening, the first opening is in communication with the space section and the second opening is in communication with the collection part. The suction device is configured to generate an air flow flowing from the suction section to the collection part. Opening area of the slit shaped opening is greater than opening area of the first opening. | 1 |
BACKGROUND OF THE INVENTION
Fuel atomizing nozzles for use in gas turbines and the like commonly employ compressed air to atomize the fuel. It is also well known to employ fuel swirl chambers to produce a hollow conical form of spray. These features may be combined as disclosed in U. S. Pat. No. 3,474,970 in which compressed air is fed around the outside of an extended conical discharge orifice of a swirl chamber to atomize the conical sheet of fuel emerging from the edge of the discharge orifice. It is also well known to introduce compressed air to the inside of a fuel swirl chamber to obtain mixing of the fuel and air in order to improve atomization. A disadvantage of both of such devices is that the quantity of air which can be brought into intimate contact with the fuel is limited by geometric considerations; in the first case because the air and fuel sheets necessarily have to follow approximately parallel directions, and in the second case because the discharge orifice size is limited by the hydraulic design considerations especially if, as is usually the case, the resultant spray cone angle must be held to a desired value. As a result, in both cases insufficient air can be utilized to obtain satisfactory atomization under all conditions particularly those of high fuel flow rates and/or high fuel viscosity.
Economic and supply considerations are at present dictating the use of fuels of lower quality and higher viscosity than heretofore and, hence, it is important to obtain good fuel atomization in order to satisfy general requirements for both fuel economy and atmospheric pollution standards.
SUMMARY OF THE INVENTION
A principal object of the present invention is to provide a fuel nozzle in which the quantity of compressed air which can be supplied to the nozzle is independent of the hydraulic design limitations.
Another object of this invention is to provide a nozzle in which the air is supplied in a manner to maximize the fuel atomizing effect thereof.
Yet another object of this invention is to maintain adequate control of the conical shape of the fuel spray under widely varying conditions of operation.
Yet another object of this invention is to provide a fuel atomizing nozzle which can readily be combined with other known features of a gas turbine combustion chamber such as swirl vanes for admitting air to the primary combustion zone of the combustion chamber.
Yet another object of this invention is to provide a simplified nozzle construction having large fuel passages which are more suitable for use with low quality fuels of high viscosity and which may contain substantial amounts of solid particles.
Yet another object of this invention is to provide a nozzle having means for admitting a portion of the compressed air around the outer edge of the discharge trumpet or funnel to eliminate the collection of large drops of fuel at this point.
Yet another object of this invention is to provide a nozzle having means as aforesaid which are so arranged as to insure even circumferential distribution of said portion of the compressed air which is admitted around the outer edge of the discharge trumpet or funnel.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a central longitudinal cross-section view of a fuel nozzle having a perforated trumpet or funnel-shaped discharge orifice portion through which tangential jets of compressed air are admitted to atomize the swirling conical fuel sheet flowing toward the mouth of said trumpet or funnel-shaped discharge orifice;
FIG. 2 is a transverse cross-section view taken substantially along the line 2--2, FIG. 1;
FIG. 3 is a fragmentary longitudinal cross-section view of a modified form of nozzle similar to that of FIG. 1;
FIG. 4 is a longitudinal cross-section view of yet another form of fuel nozzle embodying the present invention;
FIG. 5 is a transverse cross-section view taken substantially along the line 5--5, FIG. 4; and
FIG. 6 is a fragmentary elevation view as viewed along the line 6--6, FIG. 4.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring first to FIGS. 1 and 2, the fuel nozzle comprises a nozzle housing 1 inserted through an opening in the front end or dome of a combustion chamber liner 2 and is secured to the combustor outer casing 3 with screws 4 as shown. The nozzle housing 1 includes a boost air inlet fitting 5, a sleeve 6 which separates the boost air from the standard compressor air, and a threaded nozzle body 7 which contains a fuel swirl plug 8, the nozzle body 7 being screw-threaded into the nozzle housing 1 and serving to clamp the sleeve 6 against the shoulder 9, the nozzle body 7 being locked as by means of the lock nut 10. As shown, the nozzle body 7 and fuel swirl plug 8 define a swirl chamber 11 into which fuel is fed through the angled slots 12. The discharge orifice 14 is extended to form a conical trumpet or funnel 15 which terminates in a sharp edge 16. The trumpet 15 is perforated by a series of tangentially disposed holes 17 which have centers lying in a plane normal to the axis of the discharge orifice 14 and trumpet 15. The nozzle housing 1 admits air from the combustor through angled passages 18 as shown in FIGS. 1 and 2 to produce a swirling air flow through the annular passage 19 defined between the bore of the nozzle housing 1 and the outer surface of the sleeve 6.
The fuel nozzle shown in FIG. 3 may be of the same construction as just described in relation to FIGS. 1 and 2 except that the downstream ends of the sleeve 6' and nozzle body 7' define an additional annular air passage 20 immediately upstream of the sharp edge 16 of the trumpet 15.
FIGS. 4-6 illustrate another embodiment of the fuel nozzle herein and, in this case, the primary body 25 and seal 26 are sandwiched between the fuel manifold 27 and the nut 28, the assembly being retained by a locking tab 29. The primary body 25 has therein a fuel swirl plug 30 which is retained by a threaded member 31 and locked in place by means of a crimp ring 32. The shroud 34 of the nozzle pilots on the serrations 35 which are angled as best shown in FIG. 6, the shroud 34 being held in place between the air boost manifold 36 and the outer nut 37. In this design two rows of holes 38 and 39 are formed in the trumpet 40, the holes 38 of one row being staggered with respect to the holes 39 in the other row so as to effectively overlap in a circumferential sense in relation to the fuel flowing along the surface of the trumpet 40. The swirl plug 30 has angled holes 41 therethrough leading into the swirl chamber 42 for discharge from the orifice 43. The outer nut 37 admits air from the combustor through angled passages 45 to produce a swirling air flow in the annular passage 46 defined between the outer surface of the shroud 34 and the inner surface of said outer nut 37.
In the normal operation of the FIG. 1 nozzle, fuel is fed into the swirl chamber 11 where it forms a free vortex with a hollow center and the fuel then flows over the edge of the discharge orifice and forms a film which in turn flows along the surface of the trumpet 15. The compressed air emerges at high velocity from the series of holes 17 and shears the fuel film at the intersections to cause breakup of the fuel into fine drops. Because the air is admitted into the trumpet 15 in swirling fashion, the resultant cloud of drops is also swirled and the radial component of velocity causes the cloud of drops to generally follow the wall of the trumpet 15 thus producing a hollow conical spray as the fuel-air mixture emerges from the trumpet 15. The hollow conical spray of fuel which is already well mixed with air is then further mixed with the combustion air entering through the annular passage 19 surrounding the fuel atomizing means which is also swirling and generally following the same conical discharge pattern. Preferably, the compressed air will be swirled in the same direction of rotation as the fuel while the combustion air may be swirled in the same or in the opposite direction depending on the degree of turbulence or mixing which may be found necessary in the particular type of combustion chamber to which the present invention is applied.
In FIG. 3 if there is a minor portion of the fuel film which passes the air holes 17 without being atomized it will reach the downstream edge 16 of the trumpet 15 where it will be atomized by the high velocity air fed to the small annular passage 20 which surrounds the edge 16 of the trumpet 15 before mixing with the air from the annular passage.
Basically the FIG. 4 nozzle is like that of FIG. 3 except that two sets of holes 38 and 39 are provided in the trumpet 40 in staggered relation for more complete atomization and, in addition, the angled vanes formed by the serrations 35 introduce compressed air as the atomized fuel emerges from the trumpet 40 and prior to mixing with combustor air in the surrounding annular passage 46. | A nozzle for atomizing fuel for use in gas turbines and the like especially suitable for atomizing fuels of high viscosity, said nozzle having a fuel swirl chamber with a trumpet or funnel-shaped orifice along which the fuel flows as a swirling conical sheet and being characterized in that said trumpet or funnel-shaped portion is perforated for admission of compressed air in swirling fashion to atomize the swirling conical sheet of fuel. | 5 |
BACKGROUND OF THE INVENTION
This invention relates to extension rods used in percussive drilling in the mining and construction industries. An extension rod transmits impact energy from a percussive drill to a drill bit, the percussive drill remaining above the surface of the ground and the drill bit penetrating below surface to a depth roughly equivalent to the length of the extension rod. Greater depths may be drilled by connecting two or more extension rods together with coupling sleeves to form an extension rod string.
There are a variety of names given extension rods as used in percussive drilling, such as drill rods, extension drill steel, sectional drill steel and extension rod. For the sake of uniformity throughout the specification, the term "extension rod" will be employed.
It has been noted in percussive drilling that bending or flexural straining has an important effect on extension rod life and that impact energy which is diverted into flexural waves has the effect of reducing energy available for breaking rock. For example, it has been noted that such flexural strain can be as high as 70% of the normal longitudinal strain, and that it is largely responsible for extension rod breakage. William A. Hustrulid, A Study of Energy Transferred to Rock and Prediction of Drilling Rates in Percussive Drilling, University of Minnesota Master of Science Thesis (1965). The flexural waves also increase surface stress up to about 50% and produce considerable tensile stresses at certain points, which contribute to a reduction in fatigue life of the extension rod. H. C. Fischer, "Stress Pulses in Percussive Drilling," International Symposium on Mining Research, Vol. II (1961). It is, therefore, not surprising that these flexural waves further reduce extension rod life in addition to the normal tensile and compressive stresses in percussive drilling. Curt Dahlin, "Factors Influencing the Life of Drill Steel Equipment," International Symposium on Mining Research, Vol. 1 (1961).
The effect of flexural strains on the life of extension rods can be compensated for by improving the resistance to flexing or bending. However, such as improvement should not be obtained by increasing the cross-sectional area of the rod zone because this will increase both the weight and cost of the extension rod.
In rotary drilling operations the fatigue life of drill collars has been enhanced by providing greater flexibility in the zone adjacent to the threaded ends of the collar. See for example U.S. Pat. No. 3,730,286. However, rotary drill collars are not subjected to high velocity strain pulses superimposed on the rotary forces, as in percussive drilling, and flexural pulses or waves are virtually not present. Extension rods of the present invention are provided with greater rigidity through an increase in the moment of inertia, this being accomplished without increases to the cross-sectional area, as will be explained in more detail hereinafter.
As is well known in the art, rotary drilling consists of a tri-cone bit connected to a rotary drilling machine by a very long drill string. The drill string and the drilling machine comprise a large static weight which rests upon the tri-cone bit, the rotation of which under the great static weight creates a high loading which grinds or bursts the rock. In contrast, percussive drilling involves transmission of impact energy in the form of high velocity strain pulses, superimposed on the rotary forces, as discussed previously, and from this viewpoint the weight of the extension rod string is virtually irrelevant. In effect, what is being described is the difference between a static and a dynamic system. Percussive drilling with an out of hole (above ground surface) drill is efficient down to depths of about 60 ft.; beyond this point penetration is very slow due to energy losses in the extension rod string. This technique is used in quarrying, road construction, underground drilling, and pipeline construction and is fast, efficient, and highly mobile. Because of these differences in operating procedure between percussive drilling and rotary drilling, extension rods used in percussive drilling are too small to be used in rotary drilling operations. A further distinction between these two types of drilling operations lies in the removal of cuttings from the drilling hole; in percussive drilling cuttings are generally removed by air, whereas in rotary drilling a drilling mud is used to create a liquid flow which will lift the cuttings from great depths. Also, the types of threads used in percussive drilling and rotary drilling are completely different. In rotary drilling, a machine is needed to unthread the drill collars, whereas in percussive drilling no special machine is needed. In fact, the extension rods may be unthreaded by simply terminating the rotary forces and maintaining the impact forces to loosen the threaded connections.
SUMMARY OF THE PRESENT INVENTION
It is an object of the present invention to increase the stiffness and strength to weight ratio of percussive extension rods without increasing either the cost or the weight of such rods. This is achieved by a percussive drill extension rod having first and second externally threaded ends, a rod zone therebetween, and a substantially round, internal bore in the threaded ends and rod zone along the longitudinal axis of the extension rod, with particular relative dimensions designed to improve performance and reduce costs. The first threaded end of the extension rod has an outside diameter (TD) in the range of about 1.25 to about 2.5 inches, and the rod zone has an outside diameter (RD) within a range from about equal to the outside diameter (TD) of the first threaded end to about 1.1 times the outside diameter (TD) of the first threaded end. The first threaded end has a cross-sectional area (TDX) derived from the specific outside diameter of the threaded end (TD) selected from the given range of about 1.25 to about 2.5 inches. The rod zone has an annular cross-sectional area (RX) equal from about 0.64 to about 0.76 times the circular cross-sectional (TDX) area based upon the outside diameter (TD) of the first threaded end, the internal bore in the rod zone having a diameter (RB) equal to 2 (circular√(cross section (RDX) based on the outside diameter (RD) of the rod zone minus the annular cross section (RX) of the rod zone) divided by π). The first and second threaded ends may have equal outside diameters or unequal in which case such an extension rod is commonly called a jumbo rod.
DESCRIPTION OF THE DRAWINGS
Details and advantages of the present invention appear from the following description and the accompanying drawings in which:
FIG. 1 shows an extension rod in cross section having the maximum relative dimensions in accordance with the present invention;
FIG. 2 shows an extension rod in cross section having the minimum relative dimensions in accordance with the present invention; and
FIG. 3 shows a side elevation of one end of a drill rod having a round outside and inside shape with wrench flats in a portion thereof with the cross section along line IIIA--IIIA shown in FIG. 3A.
DETAILED DESCRIPTION OF THE INVENTION
With reference to FIG. 1, extension rod 10 is generally cylindrical with a bore 12 throughout the length of the extension rod 10 and concentric along the longitudinal axis thereof. Each end thereof comprises a threaded portion 14 for insertion into a coupling sleeve (not shown). Adjacent the threaded end 14 is an external transition zone ZL comprising an increasing frustoconical surface area; the external transition zone ZL accommodates the difference, if any, between the diameter of the threaded end 14 (TD) and the outer diameter of the rod zone 16 (RD) which is immediately adjacent the external transition zone ZL. Internally, bore 12 has a dimension of TB in the threaded end and then increases into the internal transition zone Z1 and rod zone 16. The internal transition zone Z1 (shown in FIG. 2 for clarity) accommodates the bore increase from the smaller diameter in the threaded end (TB) and the larger bore in the rod zone (RB). The internal transition zone Z1 is similar in shape to the outer transition zone ZL except that the internal transition zone does not necessarily correspond in length to the external transition zone ZL. The external transition zone ZL and the internal transition zone Z1 generally approximate a frustoconical surface, and although the drawings depict them with angled intersections with the surface areas of the rod 10, in actual practice such intersections may be rounded.
FIG. 2 is similar to FIG. 1 and depicts the minimum rod zone outer diameter RD contemplated within the present invention, i.e., RD equals TD.
FIG. 3 shows a variation in the outer surface of the rod zone 16. Wrench flat 20 may be provided to allow a means by which the extension rods may be uncoupled using a Crescent or fixed end wrench as opposed to a pipe wrench. Preferably, the wrench flat 20 is hexagonal in shape, but it can be any suitably shaped surface for making engagement with a wrench. For example, the wrench flat may be a single planar surface formed in one side of the drill rod, or two, three, four, etc., surfaces. One simple method for forming the wrench flat is by forging during the upset forging of the extension rod ends, which will be described with more particularity hereinafter. FIG. 3A shows the cross section along lines IIIA--IIIA in FIG. 3.
Throughout the specification, drawings, and claims the following symbols are used:
TABLE I______________________________________ SYMBOLS USED______________________________________TD Outside Diameter of Threaded EndTB Inside Diameter of Threaded EndTDX Cross Section in.sup.2 Based on Outside Diameter of Threaded EndRD Outside Diameter of RodRDX Cross Section in.sup.2 Based on Outside Diameter of RodRB Inside Diameter of Rodt Wall Thickness of RodRX Cross Section in.sup.2 of Rod annulusI Moment of Inertia of Rod Cross SectionIF Moment of Inertia Comparison RatioRF Cross Section Comparison RatioSF Strength to Weight Improvement RatioZL External Transition Zone LengthZl Internal Transition Zone LengthW Weight in lbs/ft of Rod Portionr Radius of Gyration of Rod Portion______________________________________
Also throughout the specification and claims, the following formulae for rounding off numerical values to the relevant significant digit has been employed:
1. Numbers with 4 or less were rounded down;
2. Numbers with 5 or more were rounded up; for example:
1. 1.4944 → 1.494
2. 1.4945 → 1.495.
The novel structure of the extension rods of the present invention may be described by the following formulae:
TABLE II______________________________________FORMULAE FOR BROAD RANGE PARAMETERS______________________________________TD 1.25" to 2.5" outside diameterTB max .38 TDTDX ##STR1##RD min TDRD max 1.1 TDRDX ##STR2##RX min .64 TDXRX max .76 TDXRB ##STR3## ##STR4##I ##STR5##RF ##STR6##IF ##STR7##W 3.384 RXr ##STR8##SF ##STR9##ZL ≧ RDZl ≧ RB______________________________________ *ISO stands for the International Organization for Standardization which publishes and sets standards for various systems, including percussive extension rods.
For purposes of comparison, the following table shows the prior art ISO Standard hollow hexagonal rod dimensions (ISO 1721 and 1722 (1974)):
TABLE III______________________________________ISO STANDARD SIZESHOLLOW HEXAGON DRILL STEELISO 1721 & 1722______________________________________Across Flats Size (A/F) 1.00 1.25 1.50 1.75 1.875d(Hole Size) (TB=RB) .331 .346 .512 .571 .630Cross Section in.sup.2 (1) .780 1.259 1.744 2.396 2.733W (lbs/ft.) (2) 2.640 4.260 5.902 8.108 9.248Moment of Inertia (I) (3) .059 .145 .301 .558 .734Radius of Gyration (r) (4) .275 .339 .415 .483 .518______________________________________(1) Cross section based on sharp cornered hexagon. ##STR10##(3) Moment of inertia I = .06 (Across Flats Size).sup.4 - .049 d.sup.4 ##STR11##
Also, for the purposes of comparison, the following table shows the prior art ISO standard hollow round drill steel rod dimensions (ISO 1719 and 1720 (1974)):
TABLE IV______________________________________ISO STANDARD SIZESHOLLOW ROUND DRILL STEELISO 1719 & 1720______________________________________Nominal Dia. 1.25 1.50 1.75 2.00Basic Size 1.276 1.555 1.831 2.071Tolerance +0 +0 +0 +0 -.027 -.039 -.055 -.063Basic Nominal Dia. (D) (1) 1.263 1.536 1.804 2.040d (Hole Size) (TB=RB) .346 .512 .571 .630Cross Section in.sup.2 (2) 1.159 1.647 2.300 2.957W lbs/ft (3) 3.921 5.574 7.783 10.006Moment of Inertia (I) (4) .124 .269 .514 .841Radius of Gyration (r) (5) .327 .404 .480 .533______________________________________ ##STR12##(2) Cross section = .7854 (D.sup.2 -d.sup.2) ##STR13##(4) Moment of inertia = I = .049 (D.sup.4 -d.sup.4) ##STR14##
By employing the formulae in Tables II, III, and IV for given thread diameters of 1.25, 1.5, 1.75, 2.0, 2.25 and 2.5 inches, the following maximum and minimum dimensions together with the corresponding properties of the extension rods of the present invention may be calculated and compared to the corresponding properties and dimensions of the ISO standard hexagonal and round hollow extension rods:
TABLE V__________________________________________________________________________DIMENSIONS AND PROPERTIES COMPARISON TABLE RX W RB tTD RD Min Max Min Max Min Max Min Max__________________________________________________________________________ (1) 1" Hex .780 nom 2.640 nom .331 nom -- (2) 1-1/4" Rd 1.159 " 3.921 " .346 " .4521.250 (3) 1.250 .785 2.656 .750 .250(4) 1.250 .785 .933 2.656 3.157 .612 .750 .250 .319 1.375 .838 .944 .216 .269 (1) 1-1/4"Hex 1.259 nom 4.260 nom .346 nom -- (2) 1-1/2"Rd 1.647 " 5.574 " .512 " .4941.500 (3) 1.500 1.259 4.260 .804 .348(4) 1.500 1.131 1.343 3.827 4.545 .735 .900 .300 .383 1.650 1.006 1.132 .259 .322 (1) 1-1/2"Hex 1.744 nom 5.902 nom .512 nom -- (2) 1-3/4"Rd 2.230 " 7.783 " .571 " .5901.750 (3) 1.750 1.744 5.902 .917 .417(4) 1.750 1.539 1.828 5.208 6.186 .857 1.050 .350 .447 1.925 1.174 1.321 .302 .376 (2) 2"Rd 2.957 nom 10.0006 nom .630 nom .6852.000 (3) 2.000 2.191 7.414 1.100 .450(4) 2.000 2.011 2.388 6.805 8.081 .980 1.200 .400 .510 2.200 1.341 1.510 .345 .430(1) 1-3/4"Hex 2.396 nom 8.108 nom .571 nom --(3) 2.250 2.545 8.612 1.350 .4502.250 (4) 2.250 2.545 3.022 8.612 10.226 1.102 1.350 .450 .574 2.475 1.509 1.699 .388 .483(1) 1-7/8"Hex 2.733 nom 9.428 nom .630 nom --(3) 2.500 3.142 10.633 1.500 .5002.500 (4) 2.500 3.142 3.731 10.633 12.626 1.225 1.500 .500 .638 2.750 1.677 1.887 .432 .537__________________________________________________________________________ I IF Min Max RF Min Max r SF__________________________________________________________________________ (1) .059 nom 1.000 1.000 .275 1.000 (2) .124 " 1.485 2.102 .327 1.1891.250 (3) .104 1.006 1.764 .364 1.324(4) .104 .113 1.006 1.764 1.912 .364 1.324 .136 .151 1.196 2.308 2.559 .402 1.462 (1) .145 1.000 1.000 .339 1.000 (2) .269 1.308 1.855 .404 1.1921.500 (3) .228 1.000 1.572 .426 1.257(4) .216 .239 .898 1.489 1.647 .437 1.289 .283 .313 1.067 1.950 2.159 .483 1.425 (1) .301 1.000 1.000 .415 1.000 (2) .514 1.319 1.708 .480 1.1571.750 (3) .425 1.000 1.412 .494 1.190(4) .400 .433 .882 1.329 1.439 .510 1.229 .524 .580 1.048 1.740 1.926 .563 1.357 (2) .841 1.000 1.00 .533 1.0002.000 (3) .712 .741 .847 .570 1.069(4) .682 .739 .680 .811 .878 .583 1.094 .893 .984 .808 1.062 1.171 .642 1.205(1) .558 1.000 1.00 .483 1.000(3) 1.093 1.062 1.959 .655 1.3562.250 (4) 1.093 1.184 1.062 1.959 2.121 .655 1.356 1.430 1.585 1.261 2.563 2.840 .724 1.499(1) .734 1.000 1.00 .518 1.000(3) 1.666 1.150 2.270 .728 1.4052.500 (4) 1.666 1.804 1.128 2.270 2.457 .728 1.405 2.181 2.415 1.339 2.972 3.290 .805 1.554__________________________________________________________________________ (1) ISO Hollow Hexagon - Table III (2) ISO Hollow Round - Table IV (3) Preferred properties and dimensions of present invention (4) Broad range properties and dimensions of present invention
From Table V, it is apparent that the present invention improves over prior art ISO standard hexagonal and round extension rods in both the strength to weight ratio (SF) and the radius of gyration (r). Furthermore, the extension rods of the present invention improve over the commonly used ISO standard hexagonal extension rods by improved moments of inertia as shown by the greater values of IF for the present invention. In particular, the relative dimensions of the extension rods of the present invention greatly improve over the ISO standard hollow extension rods by not only decreasing the required cross section but also increasing the strength to weight ratio, as shown in the following table.
TABLE VI______________________________________PROPERTIES OF THE PRESENT INVENTION COMPARED WITHHOLLOW ROUND EXTENSION ROD ISO 1719 AND 1720______________________________________TD RF SF1.25 .805 1.2291.50 .815 1.1961.75 .820 1.1732.0 .808 1.205______________________________________
The following table shows a sample calculation of a percussive drill extension rod in accordance with the present invention:
TABLE VII______________________________________Sample Calculation______________________________________TD selected 1.5 in ##STR15## = 1.767 in.sup.2RD selected 1.5 in ##STR16## = 1.767 in.sup.2RX min .64 TDX = 1.131 in.sup.2RX max .76 TDX = 1.343 in.sup.2RX selected same as ISO Std 1.25" hex = 1.259 in.sup.2 ##STR17## = .804 in ##STR18## = .348 inI .049 (1.5.sup.4 - .804.sup.4) = .228 ##STR19## = 1.572 ##STR20## = 1.0 ##STR21## = .426 ##STR22## = 1.257______________________________________
in view of the foregoing, it is readily seen that the present invention achieves manufacturing, cost, and operating advantages in increasing the moment of inertia relative to the cross section of the extension rod while also achieving improved strength to weight ratios. For example, by maintaining the cross-sectional areas of the rod zone in the preferred extension rods of the present invention the same as the ISO hexagonal extension rods but increasing the outer rod diameter in accordance with the present invention, the stiffness of the extension rods may be improved as shown by the increases in the moments of inertial listed in the Table V above.
Another advantage to be gained by enlargement of the outside diameter of the extension rod lies in an improved ability to lift cuttings from the bottom of the drilled hole. To remove cuttings effectively, the clearing between the drilled hole diameter and the outside diameter of the extension rods must be minimized in order to obtain the optimum air stream velocity consistent with providing adequate running clearance between the drilled hole and the extension rods. Effective removal of cuttings from a drilled hole generally requires an annular air velocity of 4000 feet per minute, annular air velocity being governed by the air consumption of the tool, its size, and extension rod diameter. The improvements in air velocity achieved by the present invention may be shown by calculating the air velocity according to the following formula: ##EQU1##
The extension rods of the present invention may be manufactured in the following manner. Tubing is selected for the appropriate inside (RB) and outside (RD) rod zone diameters and cut to the appropriate length. The ends of the cut tube are then heated so that the internal and external transitions zones will be properly formed. Next, the ends of the tube are upset forged, which slightly increases the outside diameter and decreases the inside diameter of the tube ends to form the desired value of TB. The outer surfaces of the ends are then machined, and threaded so that the selected value of TD is achieved. When the selected value of RD is larger than the selected value of TD, the outside diameter (RD) of the tube would be swaged down locally at each end to approximate TD; then the tube would be heated and upset forged as before.
Instead of providing the extension rod with two threaded ends of equal diameter, one threaded end may have a diameter greater than the other end, such an extension rod being known as a jumbo rod. Jumbo rods are not coupled together and are commonly used for holes up to 16 feet in depth. The smaller thread diameter at one end permits use of a smaller than standard drill bit, while retaining the advantage of a larger thread, coupling, and striker bar at the machine end. These rods are used largely on multi-boom equipment for production drilling in mineral extraction and tunneling. A jumbo rod in accordance with the present invention would have all of the pertinent dimensions based upon the smaller thread diameter so that such a rod would be essentially identical to a rod with equal thread diameters at each end in accordance with the present invention, except that one end would have a larger thread diameter. Basing the pertinent dimensions on the smaller thread diameter is accomplished in the smaller manner as the sample calculation in Table VII above. In manufacturing a jumbo rod in accordance with the present invention, the same method outlined above is used except that one end is upset forged to a greater degree to provide the larger thread diameter at one end; as a result thereof the thread bore diameter (TB) at that end will correspond in relative size to the larger thread diameter. One example of a series of jumbo rods in accordance with the present invention would be as follows:
______________________________________Smaller LargerTD TD______________________________________1.25 1.501.50 1.751.75 2.002.00 2.252.25 2.502.50 2.75______________________________________
with the balance of the pertinent dimensions being listed in Table V under the appropriate entries based upon the smaller TD. It will be recognized that the larger TD in the above list is one full size greater than the smaller TD but that it could be more or less without departing from the scope of the present invention. | A percussive drill extension rod having first and second externally threaded ends, a rod zone therebetween, and a substantially round, internal bore in the threaded ends and rod zone along the longitudinal axis of the extension rod, with particular relative dimensions designed to improve performance and reduce costs. The first threaded end of the extension rod has an outside diameter (TD) in the range of about 1.25 to about 2.5 inches, and the rod zone has an outside diameter (RD) within a range from about equal to the outside diameter (TD) of the first threaded end to about 1.1 times the outside diameter (TD) of the first threaded end. The first threaded end has a cross-sectional area (TDX) derived from the specific outside diameter of the threaded end (TD) selected from the given range of about 1.25 to about 2.5 inches. The rod zone has an annular cross-sectional area (RX) equal from about 0.64 to about 0.76 times the circular cross-sectional area (TDX) based upon the outside diameter (TD) of the first threaded end, the internal bore in the rod zone having a diameter (RB) equal to 2 (√(circular cross section (RDX) based on the outside diameter (RD) of the rod zone minus the annular cross section (RX) of the rod zone) divided by π). The first and second threaded ends may have equal outside diameters or unequal in which case such an extension rod is commonly called a jumbo rod. | 4 |
BACKGROUND OF THE INVENTION
This invention relates to improved cord locking devices for retaining a cord or cords against longitudinal movement relative to the unit.
One type of cord lock currently on the market includes two essentially cup-shaped elements having telescopically interfitting cylindrical side walls one of which is slidably movable into and out of the other, with a spring resisting movement of the parts relatively together. The two cylindrical side walls contain apertures which are moveable to positions of alignment when the two elements are pressed relatively together, and through which apertures a cord or cords can extend, with the cords being locked against longitudinal movement relative to the interfitting parts when the latter are released for limited separating movement under the influence of the spring. The side wall apertures in the two cylindrical parts are of substantially circular configuration.
SUMMARY OF THE INVENTION
The cord locking devices of the present invention are of the above discussed general type, but incorporate improvements enabling the device as a whole to be reduced considerably in size, and as a result be more convenient and more easily handled and manipulated in use. In addition, a unit embodying the invention is capable of gripping a cord more effectively than the discussed prior art arrangements, to resist longitudinal movement of the cord or cords relative to the device with a greater locking force. A particular feature of the invention resides in the construction of the two relatively movable parts in a manner minimizing the amount of relative movement required between released and locking conditions.
A device embodying the invention includes a body having a passage in which a plunger is slidably movable along an axis, and containing apertures which can be moved into essential alignment to pass a cord, as discussed above, with the plunger being spring urged outwardly relative to the body to locking position. The configuration of the apertures in the body and plunger is of considerable significance in limiting the range of movement which is required of the plunger relative to the body. To minimize such movement, the apertures are formed to be of oblong or elongated outline configuration rather than the circular shape of the prior art units. The narrow dimension of the openings extends in the direction of axial movement of the plunger, while the greater dimension of the opening is essentially in a plane disposed generally transversely of the axis. With such elongated apertures in the plunger and body, very little plunger movement is required whether one cord or two cords may be passed through the device.
To maximize the gripping effectivenesss of the plunger and body on the cord or cords, the gripping edges which are formed on these units and define edges of the cord passing apertures are shaped to have sharpened sectional configuration, to thereby bite into the cords and very positively resist their longitudinal movement. Preferably, the spring retains the body and plunger against separation when no cord is present. dr
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other features and objects of the invention will be better understood from the following detailed description of the typical embodiments illustrated in the accompanying drawings in which:
FIG. 1 is a central section through a first form of cord locking device constructed in accordance with the invention;
FIG. 2 is a reduced plan view taken on line 2--2 of FIG. 1;
FIG. 3 is a side view taken on line 3--3 of FIG. 1, with the cord partially broken away to better reveal the structure of the other parts;
FIG. 4 is a reduced scale view similar to FIG. 1, showing the device in its cord releasing condition;
FIG. 4a is a view taken on the line 4a--4a of FIG. 4 illustrating the lower spring retainer,
FIGS. 5 and 6 are fragmentary sections taken on lines 5--5 and 6--6 respectfully of FIG. 1;
FIG. 7 is a view similar to FIG. 1, but showing a variational form of the invention;
FIG. 8 is a reduced scale plan view taken on line 8--8 of FIG. 7; and
FIG. 9 is a view taken on line 9--9 of FIG. 8.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The first form of locking device 10 which is illustrated FIGS. 1 to 6 is typically illustrated as utilized for locking a single cord 11 against longitudinal movement relative to the device. However, this device 10 may also be utilized for locking two side by side cords against longitudinal movement, in the manner illustrated in conjunction with the second form of the invention shown in FIGS. 8 to 10. Also, the device 10a of FIGS. 8 to 10 can be employed for holding a single cord as in FIGS. 1 to 6.
As seen best in FIG. 1, the device 10 includes an outer body 12, preferably having an external spherical surface 13 centered about the point 14. A plunger 15 is manually depressable from the locking position of FIG. 1 to the cord releasing position of FIG. 4 against the tendency of a return spring 16.
Internally, the spherical body 13 contains a cylindrical passage 17 centered about an axis 18 which is vertical in FIG. 1 and which extends diametrically with respect to spherical surface 13 and extends through the center 14 of that surface. A counterbore 19 is formed at the lower end of cylindrical passage 17, with an annular transverse shoulder 20 between the main passage and counterbore, and with the body passage being closed at its lower end by a transverse shoulder 21 against which the lower end of compression coil spring 16 bears.
The upper end of cylindrical passage 17 in the body opens upwardly to the exterior of the body, through a circular opening 22, within which the plunger 15 is slidably received. At its upper end, the plunger has a portion 23 projecting upwardly beyond the body and accessible for engagement by the thumb or finger of a user to depress the plunger.
At opposite sides of the plunger as viewed in FIG. 1, the two side wall portions 24 and 25 of body 12 contain a pair of aligned apertures 26 and 27 extending along and centered about an axis 28 which extends diametrically with respect to spherical surface 13 and through center 14 and is perpendicular to and intersects plunger axis 18. The plunger also contains an aperture 29 which in the FIG. 4 position of the plunger is aligned with apertures 26 and 27 and centered about the same axis 28. All three of the apertures 26, 27 and 29 are of identical cross section transversely of axis 28 except insofar as the tops of the apertures 26 and 27 are altered slightly to provide two essentially sharp gripping edges 30 and 31, which edges are curved as in FIG. 6 to have their highest points at their centers for urging an engaged cord or cords toward a centered location. As seen in FIGS. 5 and 6, the apertures 26, 27 and 29 are of oblong rather than circular cross sectional configuration transversely of axis 28, to have vertical dimensions x which are relatively small, and horizontal dimensions y which are greater than dimension x and typcially equal to approximately twice the height dimension x. The cord or cords 11 to be locked by the device may have a normal diameter corresponding approximately to the dimension x. Apertures 26, 27 and 29 may have rounded ends at 32 and 33 (FIG. 3).
The two apertures 26 and 27 are of uniform cross section transversely of axis 28 along their entire left to right extents (as viewed in FIG. 1), except that at the locations of the gripping edges 30 and 31, adjacent inner cylindrical surface 17 of the body, the top walls of apertures 26 and 27 project downwardly (across the entire lateral extent of the top of each of these apertures between the two locations 134 and 135 of FIGS. 3 and 6). The edge 31 is defined by two surfaces which converge toward one another and merge at the sharpened extremities of the edges, and which are disposed at an angle a to one another which is substantially less than 90 degrees. The two surfaces thus referred to are the inner cylindrical surface 17 of the body 35, and an inclined surface 36 extending downwardly and inwardly toward edge 31. The second edge 30 has the same sharpened sectional configuration.
Plunger 15 has a cylindrical external surface 37 which is a fairly close fit within and slidably engages cylindrical body surface 17 to effectively guide plunger 15 for the desired movement upwardly and downwardly along axis 18 relative to the body. This cylindrical surface 37 on the plunger continues downwardly to the lower end of plunger 15, except as that surface is interrupted at the locations of intersection of the opposite ends of aperture 29 with surface 37, and at the locations of recesses 44 beneath the opposite ends of aperture 29 where the plunger is shaped to form edges 38 and 39 of sharpened sectional configuration. These edges extend laterally between the locations 40 and 41 of FIG. 5, and like edges 30 and 31 are defined by surfaces converging together at an angle b substantially less than 90 degrees. The upper of these converging surfaces is formed by the bottom surface of aperture 29 at 42, while the second surface 43 extends downwardly and radially inwardly from edge 38 or 39 to a reduced diameter cylindrical surface 144 of the corresponding recess 44. The upper end of spring 16 is received and located within a downwardly facing recess 45 formed in the underside of the plunger and is a close fit within a cylindrical bore 145 formed in the top of this recess.
The upper and lower ends of the spring are desirably connected to the plunger and body respectively in a manner retaining the upper end of the spring against separation from the plunger and retaining the lower end of the spring against separation from the body, to thus secure the plunger and body together through the spring when no cord is present. For this purpose, the spring may be a tight friction fit within each of the bores 19 and 145, and preferably these bores also have small typically rounded detent projections or lugs 119 (FIGS. 1, 4 and 4a) extending radially inwardly a short distance at one or more points about the periphery of the spring, to a diameter requiring that the end turns of the spring snap past lugs 119 upon initial assembly of the parts to lock the parts together as discussed.
In using the device of FIGS. 1 to 6, a person first presses plunger 15 downwardly against the tendency of the compression spring 16 from the FIG. 1 position to the FIG. 4 position in which apertures 26, 27 and 29 are aligned with one another along axis 28. In that condition, a cord or pair or cords 11 can be inserted easily through the apertures 26, 27 and 29, and upon subsequent release of plunger 15 the spring 16 urges the plunger upwardly to the FIG. 1 position to tightly clamp the cord or cords between body edges 30 and 31 and plunger edges 38 and 39. In that condition, the sharp edges 30, 31, 38 and 39 tend to bite into the cord and grip it in a manner very positively locking the cord or cords against longitudinal movement. Also, the relatively small dimension x of the apertures in the direction of axis 18 assists in minimizing the amount of movement required of the plunger between its locking and released conditions.
The variational form of the invention illustrated at 10a in FIGS. 7 to 9 is structurally very similar to the device 10 of FIG. 1 except for a reduction in external diameter of the outer spherical surface 13a of body 12a, and the provision of a projection 46 at the lower end of the body and of a size and shape similar to a projection 47 at the upper end of the plunger 15a. Projection 46 is essentially cylindrical, being defined by a cylindrical side wall 48 centered about the main axis 18a of plunger movement, and having a transverse end wall 49 normal to axis 18a. The lower end of spring 16a can then project downwardly into, and be frictionally or otherwise retained within, the cylindrical recess formed in the interior of hollow projection 46 of the body, and bear against bottom wall 49 to allow the use of a fairly long spring in spite of the small diameter of the main spherical surface 13a of the body. The upper end of the spring bears against and is frictionally or otherwise secured to the plunger in the same manner discussed in connection with the first form of the invention, and tends to urge the plunger to the locking position illustrated in FIG. 7. As will be apparent, the springs 16 and 16a of both forms of the invention of course are still under compression in the locking condition of FIGS. 1 and 7, and when the cords are not present these springs will urge the plungers upwardly well beyond the illustrated positions and to locations in which the plunger aperture is completely upwardly beyond the body apertures, with the close fits at both ends of spring retaining the three parts together even when no cord is present.
The projection 47 formed at the upper end of plunger 15a of FIGS. 7 to 9 is of externally cylindrical configuration corresponding essentially to that of the lower projection 46, and in particular may have an outer cylindrical surface 51 centered about axis 18a and of a diameter corresponding to the outer surface of side wall 48 of projection 46. The top of projection 47 may be defined by a flat surface 52 disposed transversely of axis 18a, and disposed parallel to the undersurface 57 of projection 46, with these surfaces being spaced a common distance radially outwardly from center 14a. The apertures 26a, 27a, and 29a of FIG. 7 may be shaped essentially the same as apertures 26, 27 and 29 of FIG. 1, and the sharp gripping projections 30a, 31a, 38a and 39a may also be shaped essentially the same as the corresponding projections of FIG. 1 and serve the same purpose.
The use of the FIG. 7 device is the same as discussed in connection with FIG. 1, but as previously indicated we have typically illustrated in FIGS. 7 to 9 the use of the device in conjunction with two cords 11a, rather than the single cord 11 of FIG. 1. As seen in FIG. 1, each of the two cords preferably has a normal external diameter corresponding approximately to the vertical extent of the apertures 26a, 27a, and 29a. The horizontal extent of the apertures, being preferably approximately twice as great as the diameter of the individual cords, as dimensioned to easily but fairly closely receive and confine the two cords 11a in side-by-side relation, so that these cords when first passed through the apertures will occupy approximately the entire cross sectional area of the apertures, and will then be compressed and tightly clamped when the plunger is released to the FIG. 7 condition.
While certain specific embodiments of the present invention have been disclosed as typical, the invention is of course not limited to these particular forms, but rather is applicable broadly to all such variations as fall within the scope of the appended claims. | A cord lock having a body containing a plunger which can be pressed inwardly relative to the body against the resistance of an actuating spring, with the body and plunger having apertures through which a cord or cords can extend and which have edges acting to grip the cords when the plunger is in a predetermined locking position. The apertures are desirably of oblong sectional shape, and the gripping edges of the plunger and body are preferably sharpened in a relation assuring effective clamping of the cord. | 5 |
DISCUSSION OF THE PRIOR ART
Shear wave vibrators are well known as exemplified by U.S. Pat. No. 4,135,599 issued Jan. 23, 1979, to Delbert W. Fair. In the past shear wave vibrators of the type described in U.S. Pat. No. 4,135,599 have been operated by a hydraulic source, such as, for example, a hydraulic fluid reservoir which is connected to a hydraulic pump, which hydraulic pump increases the pressure of the fluid to that required for the hydraulic pistons which operate the shear wave vibrator. The fluid is communicated from the hydraulic pump to the control valves which are connected to the shear wave vibrator. The control valves exhaust into a sump. Normally, several accumulators are necessary on the input and output of the various hydraulic connections to prevent cavitation and other undesirable effects associated with the hydraulic system. In the case of an underwater shear wave vibrator, two alternatives are available to generate the hydraulic fluid necessary to operate the vibrator. One method to be to convey the fluids down a long extended pipe to the hydraulic control valve, and the second method would be to have the hydraulic power supply at the shear wave vibrator with the hydraulic pump being driven by an electrical motor which receives power from the surface. Such an apparatus, of course, requires hydraulic oil cooling equipment on the vibrator, and all the necessary apparatus including reservoirs and accumulators which are necessary to have a properly operating hydraulic system. U.S. Pat. No. 3,205,969 describes a hydraulic system where water is taken through a filter into a hydraulic motor and then sent to a sink where the material from the sink is pumped out back to the water. U.S. Pat. No. 3,205,969 does not describe or refer to an underwater vibrator but does teach utilization of water to operate a hydraulic motor which functions by a differential pressure created by movement of the objects carrying the device above described. No patent known to Applicant teaches the utilization of the sea water as the source of hydraulic fluid to operate the vibrator itself.
BRIEF DESCRIPTION OF THE INVENTION
This invention contemplates the use of sea water as the main hydraulic source for operating the underwater shear wave vibrator. The water is drawn in through a filter and conveyed through a conduit to the hydraulic pump. The water leaves the hydraulic pump and is communicated to an accumulator and to the input or pressure port of the hydraulic control valve. The output or return port of the hydraulic control valve is coupled to the sea water. An electrical motor, receiving its power from a remote location such as a ship on the surface of the water, is coupled to and drives the hydraulic pumps. The control ports of the control valve are coupled in the usual manner to the pistons inside the mass of the hydraulic vibrator. Using a proper control signal the control valve will direct hydraulic fluid to one side or the other of the pistons causing the pistons to oscillate within the mass, transmitting force to the housing of the shear wave vibrator and through the coupling apparatus on the shear wave vibrator to the sea bed.
BRIEF DESCRIPTION OF THE FIGURE
FIG. 1 depicts the shear wave generator for underwater use.
DETAILED DESCRIPTION OF THE INVENTION
The shear wave vibrator illustrated in this invention is a standard shear wave vibrator fully described in U.S. Pat. No. 4,135,599 as previously discussed. Basically, the vibrator comprises a housing 10 which includes a lower half 11, an upper half 12, and end plates 13. A bracket 14 is connected to end plate 13 and coupled to ground engaging means 15 to the vibrator. Ground engaging means 15 is of a wedge or pyramidal-type construction and provides anchoring of the vibrator to the seabed during operation. Inside housing 10 is a pair of shafts 16 mounted horizontally between end plates 13 (the second shaft is not illustrated in the FIGURE). Shaft 16 passes through a mass 17 and is hydraulically sealed at 18 to prevent the escape of hydraulic fluids into the housing. Shaft 16 contains pistons 19 which are confined in a cylinder 20 in mass 17. Hydraulic passageways are coupled from each side of piston 19 to control valve 21. The hydraulic system of this invention essentially is comprised of a filter 22 which has a water inlet as illustrated by arrows 23 and an outlet 24 which is coupled by a conduit 25 to the inlet 26 of a hydraulic pump 27. An outlet 28 of hydraulic pump 27 is connected by a conduit 29 to a "T" connection 30. One branch of the "T" is coupled by a conduit 31 to an accumulator 32 while the remaining branch of 30 is coupled through a conduit 33 to the inlet 34 of control valve 21. The outlet 35 of control valve 20 is coupled through conduit 36 to an outlet 37 which exhausts into the sea water generally referred to by number 38. The entire vibrator is supported by its cable means 39 which may be coupled to a single cable or a plurality of cables (not illustrated in the FIGURE). Seabed engaging means 15, when the vibrator is in operation, will normally be coupled to and engaging the seabed 40. A cable 41 is connected between an electrical power supply at the surface of the water from a surface vessel, such as a boat, which is not illustrated, and a terminal box 42. A motor 43 has its input connected to cable 41 in order to receive adequate power for driving motor 43 and its mechanical output connected through a shaft 44, a coupler 45, to a second shaft 46 which drives hydraulic pump 27. Also in the terminal box will be a wire 47 which contains the control signals necessary to operate control valve 31, therefore, wire 47 is connected to the input 48 of control valve 21. Cable 41 may also contain a conduit for bringing air pressure down to the vibrator and other signals from the vibrator to the surface. The air may be used for pressurizing the internals of the vibrator to maintain the vibrator at a higher pressure than the outside sea water so that sea water will not seep into the vibrator housing and hinder the operation of movement of the vibrator housing about mass 17. Furthermore, sensors may be necessary which have not been illustrated but are well known in the art which would transmit air pressure readings inside the vibrator to the surface and any other necessary signals which need to be transmitted from the vibrator to the surface for proper control of the vibrating and seismic surveying system.
OPERATION
Operation of the vibrator is similar to any shear wave vibrator either on land or on the sea with the exception of the unique functions described in this invention. Basically, the cables 39 will lift the vibrator and deposit it at some particular location on seabed 40 where signals are desired to be transmitted onto the ground,. Once the vibrator is positioned, electricity will be supplied down cable 41 along with the necessary signals to control the operation of the vibrator. When power is supplied to motor 43, shaft 44 through coupler 45 will turn shaft 46 operating pump 27. Once pump 27 begins to rotate, fluid will be taken in to the inlet of filter 22 in the direction as indicated by arrows 23. Water will then be forced from outlet 24 through conduit 25 to the inlet 26 of pump 27 where the water will be pressurized to the outlet 28 through conduit 29 and 33 to the inlet 34 of control valve 21. Water will, of course, also be supplied through conduit 31 to accumulator 32. When it is desired to operate the vibrator once the system is pressurized, a control signal will be sent down cable 41 which may be transmitted through wire 47 to control to the input 48 of control valve 21. Once the signal is received at control valve 21, hydraulic fluid will be passed from conduit 34 to appropriate control valves and ports and passageways to one side or the other side of piston 19. Once one side of the piston 19 is pressured up, the housing will tend to move about mass 17, causing a force to be exhibited against one side or the other of seabed engaging means 15. Upon proper control to the input 48 of control valve 21, the fluid will gradually be decreased on one side and pressured on the other side of piston 19, causing the housing to move in the reverse direction, therefore, the signal being received at 48, upon proper control, will develop a vibrating signal which will be coupled to the seabed engaging means 15 and be transmitted into seabed 40. When the hydraulic fluid is being expelled from control valve 21, it will pass through conduits 35 and 36 to the outlet 37. The outlet 37 is shown being covered so that material cannot drop into the outlet pipe, thereby contaminating the control valve 21.
The invention basically provides a source of hydraulic fluid which can operate a large undersea vibrator without requiring an extraordinary amount of apparatus normally required to operate a hydraulic vibrator, such as an oil cooler, oil reservoir, accumulators on the inputs and outputs on all of the hydraulic use devices.
Using the sea water as the hydraulic fluid also eliminates possible contamination of the sea with hydraulic oil. In a vibrator which would normally develop 3,000-foot pounds of force, the electric motor 43 would have approximately 200 horsepower and hydraulic pump 27 would develop 3,000 pounds per square inch at 100 gallons per minute.
CONCLUSIONS
An extremely efficient undersea vibrator has been disclosed which utilizes the sea water as the main hydraulic fluid for operating a high force vibrator. The use of sea water rather than a contained hydraulic fluid reservoir provides several unique advantages in the elimination of a large amount of waste, the elimination of oil coolers, accumulators, and other necessary equipment normally associated with a self-contained hydraulic system. It is obvious that rather than a single pump, dual pumps can be used, dual motors and other modifications can be made in the above system as described. It is obvious that changes can be made in the application and still be within the spirit and scope of the invention as disclosed in the specification and appended claims. | A hydraulic drive system for an underwater vibrator has a hydraulically driven mass for generating a seismic wave into the seabed. The hydraulic drive system for the vibrator is accomplished by filtering sea water, conveying the filtered sea water to the hydraulic pump where the sea water under pressure is supplied through a control valve to the hydraulic vibrator. The output from the control valve is coupled to the sea water. The hydraulic system provides hydraulic fluid which will not need to be cooled, thereby eliminating the normal cooling system along with several necessary accumulators and sump which are used in a closed hydraulic system. | 6 |
BACKGROUND
[0001] 1. Field
[0002] The present invention relates generally to rendering media content on a computer system, and, more specifically, to providing dedications by way of a network.
[0003] 2. Description
[0004] The use of media player applications for personal computers (PCs) and other digital devices has become widespread. Many different player applications are offered by software developers. The player applications are typically available for download from a network such as the Internet, often at no cost. One widely used player application is an audio player that renders digital audio files for listening by a user. Several different digital audio data formats are in common use, with the most common being the Motion Picture Expert Group (MPEG) audio layer 3 or “MP3” format. When digital audio data is stored in a file in the well-known MP3 format, the file may be easily moved, copied, transferred, or rendered by operating system or player application software. Of course, media player applications may also render video and other forms of content as well. While the discussion of media players herein may in some cases specify audio players, it should be appreciated that the topics may apply to video and other forms of media content as well.
[0005] Users are experienced in using audio player applications to build play lists of their favorite music. Play lists are a feature of many of the available audio player applications. A user typically constructs a play list of multiple units of audio content (e.g., music files) obtained from a variety of sources. Collectively, the content of the play list may be referred to as a “program”. The individual units of content which make up the play list may be referred to as “segments” of the play list.
[0006] When the audio player application is operating according to a play list, the user may experience a successive stream of songs listed in the play list. However, once the user initiates operation of the audio player according to the play list, manual intervention by the user may be involved in order to interleave additional content with the content specified in the play list. There is typically no convenient manner by which another person may modify the user's play list, for example, to interleave a dedication. As used herein, “dedication” refers to any media content specified by a party other than the user experiencing the content. In one sense, network-based dedications are similar to the familiar radio dedications in which a friend or family member contacts the radio station and requests that a particular song “go out to X”, where X is a listener of the radio station.
[0007] Thus, there are opportunities for providing additional capabilities in digital audio applications that overcome these and other limitations of the prior art.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The features and advantages of the present invention will become apparent from the following detailed description of the present invention in which:
[0009] [0009]FIG. 1 shows an embodiment of a system according to the present invention.
[0010] [0010]FIG. 2 shows an embodiment of a system according to the present invention.
DETAILED DESCRIPTION
[0011] An embodiment of the present invention is a method and apparatus for providing dedications to a user over a network. The present invention provides a technique for insertion of dedication content between segments of an audio and/or video (henceforth “media”) program. According the present invention, when a user is listening to a series of digital media files being rendered by a media player application according to a play list or in a streaming manner, additional information may be rendered for the user in between the media files (e.g., in between songs for audio media) or even as a “voice over” during media rendering. The additional information may be specified by another person. If some of the additional information is specified in a textual format (e.g., ASCII), the text may be converted into audio for audible rendering to the user.
[0012] In one embodiment, a user may be executing an audio player application to play either locally stored digital audio files (e.g., files in MP3 or another audio format) or other streaming digital audio files (as in an Internet radio application). In embodiments of the present invention, the system plays a message and a song dedication to the user in between songs or as a voice-over during a song of the play list. Other information may also be rendered between songs or as voice overs.
[0013] Reference in the specification to “one embodiment” or “an embodiment” of the present invention means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearances of the phrase “in one embodiment” or “in an embodiment” appearing in various places throughout the specification are not necessarily all referring to the same embodiment.
[0014] [0014]FIG. 1 is a diagram of a system 100 according to an embodiment of the present invention. System 100 includes a computer system 120 for accessing the network 106 . A computer system is any device comprising a processor and memory, the memory to store instructions and data which may be input to the processor. In one embodiment, the computer system 120 comprises at least one of a PC, an Internet or network appliance, a set-top box, a handheld computer, a personal digital assistant, a personal and portable audio device, a cellular telephone, or other processing device. Network 106 may be any network or series of interconnected networks capable of transporting digital content. For example, network 106 may be a local area network (LAN), a wide area network (WAN), the Internet, a terrestrial broadcast network such as a satellite communications network, or a wireless network. A network interface (not shown) may couple to the computer system 120 and network 106 .
[0015] The computer system 120 comprises a memory 134 . The memory 134 may be any machine-readable media technology, such as Random Access Memory (RAM), Dynamic RAM (DRAM), Read-Only Memory (ROM), flash, cache, and so on. Memory 134 may store instructions and/or data represented by data signals that may be executed by a processor of the computer system 120 (processor not shown). The instructions and/or data may comprise software for performing techniques of the present invention. Memory 134 may also contain additional software and/or data (not shown).
[0016] In one embodiment, a display device 118 may be coupled to the computer system 120 . The display device receives data signals from the computer system 120 and displays information contained in the data signals to a user of system 120 . In one embodiment, computer system 120 may also comprise a machine-readable storage media 134 which acts as a memory to store instructions and data (including possibly media content), but typically comprises higher capacity and slower access speeds than does memory 134 .
[0017] Computer system 120 may receive from network information about the play list 116 of another user of another computer system (henceforth user B). In one embodiment, this information may include 1) information 116 about user B's play list, 2) an identification 110 of user B, and 3) information about whether user B is online 112 or offline 114 . “Online” means that user B is currently capable of receiving signals from the network 106 . A representation of this information, or portions thereof, may be displayed on display 118 .
[0018] By interacting with software 132 , user A may generate a message 122 to be transmitted to a computer system of user B. This message 122 may include any content, such as a greeting, a reminder, a letter, a statement of good wishes, and so on. The message 122 may take any form, including ASCII text, audio data recorded from a microphone, a video segment (with or without audio), and so on. User A may also select a dedication 124 for user B. This dedication 124 identifies media content to be experienced by user A. User A may identify one or more insertion points 126 for the message 122 and the dedication 124 in user B's play list 116 . In one embodiment, both user A and user B on online when the dedication is made, and play list 116 is the play list which user B is currently experiencing.
[0019] The message 122 and dedication 124 may be inserted together before or after a segment of the play list 116 , or in different locations in the play list 116 . The dedication 124 may identify a segment in user B's play list 116 , or media content from elsewhere. The media content identified by the dedication 124 may be stored locally to the computer system of user B, or stored by a device of the network 106 . Of course, the dedication 124 may comprise more than a mere identification; it may also comprise the actual media content for user B to experience as well. The message 122 , dedication 124 , and insertion points 126 may be transmitted from the computer system 120 to the network 106 . When user B is online, the message 122 , dedication 124 , and insertion points 126 may be received by a computer system of user B shortly after being transmitted. Alternately, the message 122 , dedication 124 , and insertion points 126 may be stored by storage of the network 106 for later access by user B.
[0020] [0020]FIG. 2 shows an embodiment 200 of a system in accordance with the present invention. A computer system 102 of user B may receive from the network 106 the message 122 , dedication 124 , and insertion points 126 . These may be stored, along with user B's play list 116 , on a machine-readable storage media 108 , such as a hard drive, solid-state memory, CD ROM, and so on. Of course, the play list 116 , message 122 , dedication 124 , and insertion points 126 may also be stored by storage of the network 106 , in which case user B may need to be online in order to experience the dedication, in a manner to be described.
[0021] The computer system 102 may comprise a memory 136 . The memory 136 may be any machine-readable media technology, such as Random Access Memory (RAM), Dynamic RAM (DRAM), Read-Only Memory (ROM), flash, cache, and so on. Memory 136 may store instructions and/or data represented by signals that may be executed by a processor of the computer system 102 (processor not shown). The instructions and/or data may comprise software for performing techniques of the present invention. Memory 136 may also comprise additional software and/or data (not shown). In one embodiment, computer system 102 may also comprise a machine-readable storage media 108 which acts as a memory to store instructions and data (including possibly media content), but typically comprises higher capacity and slower access speeds than does memory 136 . In one embodiment, the storage media 108 may comprise user B's play list 116 , the message 122 , the dedication 124 , and the insertion points 126 .
[0022] The computer system 102 may further comprise a speaker device 104 for rendering audio media content. Of course, the computer system might comprise multiple speaker devices, and/or a display device for rendering video media content. In one embodiment, the computer system 102 comprises at least one of a PC, an Internet or network appliance, a set-top box, a handheld computer, a personal digital assistant, a personal and portable audio device, a cellular telephone, or other processing device. The computer system 102 in one embodiment may be a consumer electronics device such as a home stereo or portable MP 3 player. In one embodiment, the computer system 102 may be coupled to the network 106 by a home network.
[0023] Memory 136 may comprise media player software 130 . Media player 130 may receive and process media content for rendering. In one embodiment, the media player 130 may be an audio player such as Windows Media Player (available from Microsoft Corporation), RealPlayer (available from RealNetworks, Inc.), or WinAmp (available from NullSoft Corporation), for example. In another embodiment, the media player 130 may be an application program or software plug-in that supports reception and rendering of media content streams from the network 106 . In another embodiment, the functionality of the media player 130 may be included in a browser program (such as Internet Explorer from Microsoft Corporation or Netscape Navigator (not shown)).
[0024] In one embodiment, the memory 136 may comprise Text-To-Speech software (TTS) 140 for converting text content into audio. For media content comprising a textual format (for example, ASCII), the TTS software 140 may convert the text into an audio media format recognizable as speech according to well-known methods. Such media content may be rendered by speaker 104 . In one embodiment, the TTS software 140 operates on media content according to a speech application programming interface (SAPI). In other embodiments, the TTS software 140 may be comprised by a server computer system (not shown) of the network 106 , and the converted audio media content may be transmitted over the network 106 to the computer system 102 .
[0025] The media player 130 may receive media content in accordance with the play list 116 from storage media 108 , or from the network 106 . In accordance with the play list 116 , the media player 130 may transfer audio media content to the speaker 104 for rendering.
[0026] In one embodiment, media content of the play list is stored locally by the computer system 102 by storage media 108 . Of course, the local storage media 108 could also be external to the computer system 108 , or be part of a home network or other local computing or media processing environment. For example, a user may have converted tracks from multiple compact discs (CDs) in the user's music collection from CD format to MP3 format (or other suitable digital audio format) and stored the MP3 files in the local storage. The play list 116 , dedication 124 , message 122 , and insertion points 126 may be stored locally or on storage of the network 106 .
[0027] When the media player 130 encounters a segment corresponding to one of the insertion points 126 , the message 122 may be rendered. If the message 122 is stored in a textual form, it may be converted to audio by the TTS software 140 . In one embodiment where the message 122 and dedication 124 are inserted together, the dedication 124 may also be rendered. The dedication 124 may comprise the actual media content to render, or an identification of the media unit (e.g., Uniform Resource Locator, local file descriptor, or other pointer to a song file or other media source) comprising the dedication content. The dedication 124 may identify a segment of the play list 116 or content from another source.
[0028] Alternatively, the dedication 124 and the message 122 may be inserted at different points in the play list 116 . Consider the following exemplary dedication: a message 122 comprising the text “Hello John. Good to see you back online. This one's for you—remember September in Vegas?”, and a dedication 124 identifying a song stored in an MPEG formatted media file with the URL http://www.musicland.com/john/blackjack.mp. The insertion points 116 for both the message 122 and the dedication 124 could be between segments one and two of John's play list 116 . When the media player 130 finishes segment one of the play list 116 , the message 122 could be converted to audio using the TTS software 140 and rendered on the speaker 104 . John would then hear the spoken words, “Hello John. Good to see you back online. This one's for you—remember September in Vegas?” Next, the media player 130 would attempt to receive an audio stream in well known manners from the network source http://www.musicland.com/john/blackjack.mp, e.g. the song “Blackjack”, and render it on the speaker 104 . Of course, John would need to be online to receive the song. When the dedication 124 specifies content local to system 102 , John may experience the dedication content without being online.
[0029] In one embodiment, rather than rendering the message 122 between segments of the play list 116 , the message audio may be mixed with the audio of a media segment so as to provide a “voice over.” In this case, the user who made the dedication may specify that the message should be applied as a voice over.
[0030] In the preceding description, various aspects of the present invention have been described. For purposes of explanation, specific numbers, systems and configurations were set forth in order to provide a thorough understanding of the present invention. However, it is apparent to one skilled in the art having the benefit of this disclosure that the present invention may be practiced without the specific details. In other instances, well-known features were omitted or simplified in order not to obscure the present invention.
[0031] Although some operations of the present invention (for example, TTS) are described in terms of a hardware embodiment, embodiments of the present invention may be implemented in hardware or software or firmware, or a combination thereof. Embodiments of the invention may be implemented as computer programs executing on programmable systems comprising at least one processor, a data storage system (including volatile and non-volatile memory and/or storage elements), at least one input device, and at least one output device. Program code may be applied to input data to perform the functions described herein and generate output information. The output information may be applied to one or more output devices, in known fashion. For purposes of this application, a processing system embodying the playback device components includes any system that has a processor, such as, for example, a digital signal processor (DSP), a microcontroller, an application specific integrated circuit (ASIC), or a microprocessor.
[0032] The programs may be implemented in a high level procedural or object oriented programming language to communicate with a processing system. The programs may also be implemented in assembly or machine language, if desired. In fact, the invention is not limited in scope to any particular programming language. In any case, the language may be a compiled or interpreted language.
[0033] The programs may be stored on a removable storage media or device (e.g., floppy disk drive, read only memory (ROM), CD-ROM device, flash memory device, digital versatile disk (DVD), or other storage device) readable by a general or special purpose programmable processing system, for configuring and operating the processing system when the storage media or device is read by the processing system to perform the procedures described herein. Embodiments of the invention may also be considered to be implemented as a machine-readable storage medium, configured for use with a processing system, where the storage medium so configured causes the processing system to operate in a specific and predefined manner to perform the functions described herein.
[0034] While this invention has been described with reference to illustrative embodiments, this description is not intended to be construed in a limiting sense. Various modifications of the illustrative embodiments, as well as other embodiments of the invention, which are apparent to persons skilled in the art to which the inventions pertains are deemed to lie within the spirit and scope of the invention. | A method includes receiving a dedication from a first user via a network and applying the dedication to a play list of a second user. | 8 |
FIELD OF THE INVENTION
The present invention relates to a hood for the suction and/or the filtration of the cooking fumes in a domestic kitchen.
DESCRIPTION OF THE BACKGROUND ART
Various types of hoods for domestic use are known, which are used for eliminating cooking smells in a kitchen. Such hoods are called suction hoods if they expel, outside the kitchen, the air drawn from above the stove, or filtration hoods if they recycle the air in the room, after having purified it.
In the aspiration mode, in most cases, the air is expelled from the hood in an upward direction, through a conduit contained and hidden by an overhanging wall cabinet, which expels the air towards the ceiling of the kitchen. Said conduit usually has its axis in the middle vertical plane of the hood, for aesthetic reasons if it is in view, and for reasons of standardization if it is mounted within the wall cabinet.
If the hood is fixed to a wall which is directed outside the building, the air can be expelled towards the rear part of the hood. This embodiment, which is aesthetically pleasant due to the absence of a conduit in view, is however rarely used, because it requires the hole on the wall to be previously made in a very precise position.
On the contrary, in the filtration mode, the air is usually expelled from the hood by means of louvers present in its front part. This is the simplest and cheapest embodiment, because no additional tubes are necessary and the wall cabinet arranged above the hood is free for other purposes, because it is not crossed by the conduit which conveys the air towards the outside. However, due to the fact that the air expelled, this way can be very noisy (because air exits the hood at the users' head height). Often it is preferred to expel the air towards the ceiling, by means of a conduit being hidden in an overhanging wall cabinet which ends on top of the wall cabinet itself.
Summarizing, therefore, known hoods may provide for four operating modes: a filtration mode towards the front part (FA), a filtration mode towards the upper part (FA), a suction mode towards the rear part (AP), and a suction mode towards the upper part (AS).
In order to reduce the number of variations, known hoods are usually conceived so as to provide all the above mentioned four operating modes, which can be set in part by the installer and in part by the final user of the hood. Several users, in fact, prefer to filter and recycle the air during winter, for energy saving reasons, while they prefer to expel the fumes for the remaining part of the year.
The treatment and path of the air which crosses the hood in the upward direction is substantially identical for all the products available on the market: firstly, the air passes through a mechanical filter, called a grease filter, which also serves as a panel for closing the lower part of the hood and can be removed and cleaned by the user. The filter, which is always present, retains solid floating soil conveyed by the cooking fumes, so as to protect the hood from dirt. There are no problems in realizing a sufficiently large grease filter, but care should be taken that the air crosses it without any preferential path.
In the filtration mode, the air path further includes an activated-carbon filter, which absorbs the smells derived from the cooking. This filter has to be easily accessible, so that the user can replace it once exhausted. The efficiency and the life of this filter are improved, if its volume and section crossed by the air are large.
After having passed through the above mentioned filters, the air is then sucked by a fan which is usually of the centrifugal type, inasmuch as axial fans do not have a sufficient head, and then conveyed in a conduit towards one of the possible outlets.
In the most common case, during the installation, a plug or predetermined fracture zones determine whether the air will exit the hood in the upward or the rear direction. The user, on the other hand, by maneuvering an appropriate deflection valve which has an easily accessible rod, can cause the air to exit by the front louvers of the hood.
A hood of good quality should therefore satisfy the following requisites: a sufficient air head in the suction mode; good capacity for reducing smells in the filtration mode, and therefore a large frontal surface of the activated carbon filter; reduced noise; reduced dimensions, for optimization of the available space; and last but not least, aesthetic features are very important, and require the design of hoods of minimal height. As a general practice, the activated-carbon filter is constituted by a single cartridge which is fixed to the nosepiece of the fan (as shown in FIG. 3). In this way the installation and replacement of the exhaust cartridge are very easy but, as already said, due to the need for making hoods that are very thin, the space which remains between the grease filter and the activated-carbon filter is very small and therefore this fact requires chokes around the edge of the activated-carbon cartridge.
Said fixing mode therefore makes the grease filter not very efficient, because a great part of the air is sucked exclusively in its central zone, near the nosepiece. An unpleasant grease spot is therefore rapidly created in the central zone on the external side which makes evident a non-uniform air distribution.
From the same FIG. 3 it is evident that, according to said solution, there is no reason for mounting carbon filters having very large dimensions, inasmuch as, considering the reduced available space, preferential paths will be created within them, in correspondence of the axis of the nosepiece, while the periphery of the cartridge will not be efficiently exploited. For this reason, limits on the height of the hood also determine limits for the extension of the cross section of the activated-carbon filter, and therefore, limits on the performance of the hood in relation to filtration efficiency and charge losses.
From FIG. 4, which shows a typical development of the conduits which extend downstream of the fan, it is evident that, always due to the reduced available space, the air in the front filtration mode, is compelled to follow a tortuous path, which causes great noise and charge losses, thereby limiting the air head which can be sucked. From the same figure, it is also evident that the same conduits do not leave space for mounting the activated-carbon filter downstream of the fan, and upstream of the valve for deflecting the air towards the upper or the front part of the hood.
In order to have reduced overall dimensions, some models of hoods are partially encased within the overhanging wall cabinet, with the further drawback that, besides higher costs, the differing dimensions of various furniture products have to be taken into account.
A further drawback is in the fact that, in order to pass from a filtration mode to a suction mode, the filter cartridge has to be removed from the hood and stored in another place.
OBJECTS OF THE INVENTION
The present invention has the aim of resolving the above mentioned drawbacks. In this light, a first aim of the invention is that of allowing reduction of the height of the hood or, more generally, of allowing reduction of the dimensions of the hood in the direction parallel to the fan axis, thereby even improving the degree of uniform air flow through the grease filter.
A second aim of the present invention is that of showing how it is possible to install activated-carbon filters larger than usual ones, and whose dimensions are limited only by the plan dimensions of the hood itself and not by its thickness, so as to improve filtration efficiency.
Another aim of the present invention is that of providing a hood which, in the most general case, allows for change among the four operating modes without the necessity of a flow deflection valve or closure plugs for the outlets not being used.
These and further aims are attained according to the present invention by a hood for the suction and/or the filtration of cooking fumes in a domestic kitchen having the features of the annexed claims.
BRIEF DESCRIPTION OF THE DRAWINGS
Further characteristics and advantages of the present invention will be clear from an illustration of the hoods according to the prior art and from the description of some preferred, but not exclusive, embodiments of the hood according to the invention, which are shown as a pure example in the following figures (wherein the parts which do not pertain to the invention have been omitted)
FIG. 1 is a side view of a hood, as it is normally installed above a cooking stove, which shows the air exit zones in the different operating modes, i.e., filtration or suction.
FIGS. 2 to 4 show how the filter means and the air conduits are arranged in a hood according to the prior art. In particular, FIG. 2 shows in a schematic way the air flow from the drawing zone towards one of the three possible outlets. FIG. 3 shows with a side cross section the activated-carbon filter fixed to the nosepiece of the fan and the effects of this assembly on the flow of the sucked air. FIG. 4 shows, with a horizontal cross section, how the air conduits from the fan scroll to the three possible outlets are realized in the known hoods;
FIGS. 5A-F show, with an exploded axonometric schematic view, in accordance with one of the preferred embodiments of the invention which does not require any additional flow deflection means, the four operating mode of the hood which are possible in accordance with the invention;
FIGS. 6A-F show, with an exploded axonometric and schematic view, substantially similar to that of FIGS. 5A-F a container being of simplified construction, where the material constituting its external surface is present only in the essential points for structural reasons and for attaining the aim of the invention;
FIG. 7 shows, with an axonometric view, the assembly of the ventilation group and a flow deflection filter according to the embodiment of the invention shown in FIGS. 5A-F;
FIG. 8 shows, with a plan view, the assembly of the ventilation group and a flow deflection filter according to the embodiment of the invention shown in FIGS. 5A-F;
FIG. 9 shows, for clarity purposes, a section of FIG. 8 according to line A--A;
FIG. 10 shows, with an axonometric view, the assembly of the ventilation group and a flow deflection filter according to a different possible embodiment of the invention;
FIG. 11 shows, with a plan view, the assembly of the ventilation group and a flow deflection filter according to the embodiment of the invention shown in FIG. 10;
FIGS. 12A-D show, with an exploded axonometric and schematic view and in accordance with the embodiment of FIG. 10, the flow deflection filter with the container according to the invention arranged in the two advantageous position for said embodiment;
FIGS. 12E-H show, with an exploded axonometric and schematic view, the flow deflection filter with the container according to the invention and in accordance with FIGS. 12E-H, but having a cylindrical shape instead of a parallelepiped one;
FIGS. 12J-L show, with an exploded axonometric and schematic view, the flow deflection filter according to an embodiment different from the preceding ones, which allows for the same operating modes already shown in FIGS. 12A-D;
FIGS. 13A-C show three cross sections of FIG. 11 according to line B--B, for indicating the air path respectively in the Front Filtration mode, the Upper Filtration mode and the Upper Suction mode;
FIG. 14 shows, with a vertical cross section, one of the possible embodiments of the container according to the invention:
FIG. 15 shows, with a vertical cross section, a further possible embodiment of the container according to the invention;
FIGS. 16A and B show graphic symbols stamped on the two main surfaces of the container in accordance with the embodiment of the invention shown in FIGS. 5A-F.
DETAILED DESCRIPTION OF THE INVENTION
With reference to FIG. 1, the installation of a hood 1 is usually carried out by fixing it underneath a wall cabinet 3. The air sucked from a cooking stove, when filtered, may be recycled in the room through louvers present on the front part 2 of the hood 1, or through a tube 4 hidden by said wall cabinet 3. Alternatively, when the sucked air is expelled, this can occur by means of said tube 4, which is connected to a further conduit 5 directed outside of the room, or directly through a hole 6 being present in the rear part of the hood 1.
With reference to FIG. 2, the air flow, following the direction of the arrows, crosses a grease filter 7, and then, according to prior art, an activated-carbon filter 8 (when present), a suction fan and the relative scroll 9. A valve 10, when in position 10A, provides for deflecting the flow in the direction of the front part 2, while in position 10B directs the flow in the direction of one of the two exits, the upper one 4 or the rear one 6, a plug 11, or other suitable closure means, established at installation, if the hood must have an upper exit 4 or a rear exit 6. In the latter case, the plug is mounted in the position 11B.
In FIG. 3 the grease filter 7 and the activated-carbon filter 8 are shown, according to another pertinent solution of the prior art, the filter 8 having a lower surface 8A permeable to the air and a side wall 8B of a compact material. The filter 8 is mounted on the nosepiece 9A of the fan, not shown in the figure, and is removed in the suction mode.
In FIG. 4, there are shown, arranged according to the prior art, a fan 9B, the deflection valve 10, the upper exit 4 or the rear exit 6, the front exit 2.
In FIGS. 5A-F an envelope 12 is shown according to a first possible embodiment of the invention, which has an air inlet 13 connected to the discharge of the fan, not shown in the figure. The inlet 13 is subdivided into two zones, an upper one 13A and a lower 13B one, being separated in the figure by a dotted line. The figure shows furthermore outlets 14, 15, 16, for the connection, respectively, with the front exit 2, the upper exit 4 and the rear exit 6 of FIG. 1. Under the envelope 12 a hollow means, or container 17, is shown, according to a first embodiment of the invention, in the following four possible advantageous positions:
FIG. 5B indicates the position in which said container 17 is arranged in the installation provided for the front filtration operating mode (FA)
FIG. 5C indicates the position in which said container 17 is arranged in the installation provided for the upper filtration operating mode (FS). The position shown in FIG. 5C is obtained from the previous one FIG. 5B, by rotating the container 17 of 180° around the vertical axis.
FIG. 5D indicates the position in which said container 17 is arranged in the installation provided for the rear suction operating mode (AP). The position FIG. 5D is obtained from the previous one (FIG. 5C, by overturning the container 17.
FIG. 5E indicates the position in which said container 17 is arranged in the installation provided for the upper suction operating mode (FA). The position shown in FIG. 5E is obtained from the previous one FIG. 5D, by rotating the container 17 of 180° around the vertical axis.
References 18A, 18B, 18C, 18D, 18E, 18F, 18G indicate different openings provided in the container 17. A lower cover 19 or other closure means is used for closing the container 17 according to one of the positions FIGS. 5B-E within the envelope or seat 12. The hatched zone 20 indicates a medium zone, wherein air treatment means are located, when being present inside the container 17. The treatment means are not represented in the figure, for clarity purposes.
In FIG. 6, with 12 the same envelope of FIGS. 5A-F is indicated. Reference numerals FIGS. 6B-E indicate four different positions for a single air flow deflection means 17', wherein the suffixes from "A" to "D" indicate the same position already shown in FIGS. 5A-F, references 18A', 18C', 18F' indicate openings having the same function of the corresponding openings 18A, 18C, 18F of FIGS. 5B-E. In FIGS. 6B-E there is a single opening 18BE' corresponding to the two openings 18B and 18E in FIGS. 5B-E. The hatched zone 20 indicates the position for the air treatment means being eventually present, similarly to FIGS. 5A-F. The lower closure means is indicated by reference numeral 19. The hollow means 17' has the same function as the container 17 of FIGS. 5B-E, but in the case shown in FIGS. 6A-F, it is formed by a sort of frame, which has walls only where necessary for functional or structural reasons.
In FIGS. 7 and 8, the openings in the envelope 12 are indicated, with the same reference numbers as in FIG. 5A. Therefore, 13 is the inlet for the air coming from the scroll 9, while 14, 15, 16 indicate respectively the front exit, the upper exit and the rear exit.
FIG. 9 shows in section the grease filter 7, the nosepiece 9A, the fan 9B, the scroll 9, the opening 13A-13B, the envelope 12 with the relevant openings 14, 15 and 16. The deflection means 17' is in the position shown in FIG. 6B, corresponding to the upper filtration mode (FS). There are a lower closure means 19 and a zone 20A delimited by air permeable walls 20B, which contains the air treatment means, such as an activated-carbon filter.
FIGS. 10 and 11 refer to an embodiment of the invention, which differs from that of FIGS. 5 to 9. However, for clarity reasons, similar components are indicated with the same numbers already utilized in the previous Figures. Thus, an envelope 12 is shown, having an opening 14 in the direction of the front part, a scroll with an inlet nosepiece 9A and finally two air outlets, i.e, one, indicated with 13, towards the envelope 12, and the other indicated with 15, towards the upper discharge of the hood.
In FIGS. 12A-B there is shown, in accordance with a second possible embodiment of the invention an envelope 12' having an air inlet opening 13', being divided into the two zones 13A' and 13B', and connected to the discharge of the fan, not shown in the Figure. Furthermore, there are shown the outlet 14' towards the front discharge 2 of FIG. 1. Under the envelope 12 a flow deflection means 17" is indicated, in the position shown in FIG. 12B provided for the front filtration operating mode (FA). In 17B, the container 17" is shown in the position being provided for the upper filtration operating mode (FS) . References 18A", 18B", 18C", 18D" show different openings provided in said container, even if they do not necessarily correspond to those shown in FIGS. 5 and 6. The cover 19 of a lower closure means is provided for closing the container 17" according to one of the positions shown in FIGS. 12B or 12C within the envelope 12. The hatched part 20 indicates a zone being delimited by air permeable walls, which contains the air treatment means, such as the cited activated-carbon filter, being eventually present within the container 17".
In FIGS. 12E-H a device is shown, functionally similar to that of FIGS. 12A-D, but having a substantially cylindrical shape, where the homologous parts have been indicated with the same reference numbers utilized in FIGS. 12A-D. It is evident that, in the same way, a cylindrical device derived from FIGS. 5A-F could be obtained.
In FIG. 12J-L a further embodiment of the deflection device of the hood according to invention is shown. The homologous parts have been indicated with the same reference numbers utilized in FIG. 12.
In FIGS. 13A-C there are shown the inlet nosepiece 9A of the scroll 9, the fan 9B, a deflection throttle-valve 21 for the air flow, in the possible positions 21A and 21B, the container 17 having, in an intermediate position, an air permeable means to the air (such as the cited activated-carbon filter 20A), the opening 14 towards the front exit 2 of FIG. 1, the outlet 15 in the direction of the upper part, and the closure means 19 of the envelope 12.
In FIG. 14 the container 17" is shown in section according to the position shown in FIG. 12C, and an incorporated air treatment means 20. In FIG. 15 the container 17" is shown in section, according to the position shown in FIG. 12C, with a housing seat 22 and the air treatment means 20A being evidenced.
In FIGS. 16A and B the container 17 is shown in accordance with FIGS. 5A and B, respectively, which has graphic symbols FA, FS, AS and AP. The container 17 is represented in plan, according to the positions shown in FIGS. 5B and 5C.
It is clear that, though not represented, many other embodiments are possible for the system without departing from the inventive idea, some of which will be briefly cited in the following description of the function.
The function and the advantages of the flow deflection filter according to invention will be now described.
With reference to FIGS. 7 and 8, the air sucked by the fan is introduced through the scroll 9 in the envelope 12. If the envelope 12, instead of providing for deflection means, would be closed downwards by the cover 19 of FIG. 5F, the air could simultaneously exit by the outlets 14, 15 and 16. On the contrary, with reference to FIG. 5, if the container 17 is arranged within the envelope 12 in any position and said envelope 12 is closed with the cover 19, it is clear that said container 17 partially obstructs the inlet 13 (part 13A or part 13B), and two of the three outlets 14, 15 and 16. In fact, said container 17 has a size which enables entry into the envelope 12 with good precision so that air can pass only through the free openings, without any substantial undesired leak through skylights and fissures. If the container 17 is inserted in the position shown in FIG. 5B, corresponding to the cited front filtration operating mode (FA), the air can enter the envelope 12 only through the zone 13B of the inlet 13, which is left free by the opening 18A of the container 17, and can exit only in the direction of the front part 2 of FIG. 1 through the outlet 14, which is left free by the opening 18B, and only after having crossed the middle plane 20 of said container 17, while the outlets 15 and 16 are closed by the walls of the same container 17.
Similarly with the container 17 being rotated by 180° in the position shown in FIG. 5C, i.e, for the so-called upper filtration mode (FS), the air enters by the openings 13A and 18C, crosses the middle plane 20 and then exits by the outlet 15, which is left free by the opening 18D, towards the upper discharge 4 of FIG. 1. By overturning the container 17 in the position 17C, which corresponds to the rear suction operating mode (AP), the air enters the envelope 12 and the container 17 through the facing openings 13B and 18E, and therefore the air, without crossing the meddle plane storey 20, exits by the openings 18B and 16 in the direction of the rear part 6 of FIG. 1.
Finally, by again rotating the envelope by 180°, the position shown in FIG. 5E is obtained, which corresponds to the upper suction operating mode (AS), in which the air enters the envelope 12 through the zone 13A of the inlet 13, which is left free by the opening 18F of the container 17. The air therefore exits by the openings 18G and 15 towards the upper discharge 4 of FIG. 1, in the same way as for the position shown in FIG. 5C, but now the air cannot cross the middle plane 20.
It is evident that the closure means 19 and the envelope 12 that houses the container 17, could be coupled to any surface, even one that is not flat, rather than on the lower face as shown in FIGS. 5A-F. For example, the cover 19 could close on a lateral face and the container 17 would be inserted in the envelope 12 in the way of a drawer. Alternatively the cover 19 may not be necessary, and can be replaced by a continuous face, without any openings, of the container 17. This would be possible, for example, when only the operating mode allowed by the positions shown in FIGS. 5B and C are provided. In this case, therefore, the opening 18G would not be necessary.
It is furthermore evident that the envelope 12, which substantially delimits a variety of surfaces housing the container 17, might be not expressly realized:, it might be totally or partially obtained by the surfaces of the surrounding bodies and means, such as for example the horizontal and vertical walls of the hood.
It is also evident that the container 17 need not necessarily have the box shape of FIGS. 5B-E but, as illustrated in FIGS. 6A-F, it could be simply composed by a sort of frame 17', having walls only where these are necessary for providing an obstacle to the air flow, or for ensuring structural sturdiness, or for supporting air treatment means eventually and advantageously contained in it.
For a greater understanding of the function, FIG. 9 illustrates the same case of FIGS. 6A-F with the means or container 17' in the position shown in FIG. 6C.
The air enters the envelope 12 by the opening 13B underlying the air permeable means 20A and disposed in the middle plane of the container 17'. Due to the fact that the outlets 14 and 16 are closed by the container 17', the air is obliged to exit only by the outlet 15, after having crossed the means 20A, that could be advantageously constituted by an activated-carbon filter or other air treatment means.
In FIGS. 10, 11, 12A-D and 13A-C a preferred embodiment of the invention is shown, for the case in which the available space in width for the hood is not sufficient to provide the outlet 15, for coupling with the upper exit conduit in the direction of channel 4 of FIG. 1, directly on the envelope 12 and, as it happens in most cases, the rear exit is not provided. In fact, if the space in width is not sufficient, said opening 15 has to be realized in correspondence with the exit of the scroll 9. In that case, for the deflection of the air flow the auxiliary deflection means 21 of FIGS. 13A-C is used. For obtaining the upper suction mode (AS), the deflection means 21 has to be set in the position 21B of FIG. 13C, while the position of the container 17 is not relevant, it being excluded from the air circuit. On the other hand for obtaining the filtration mode, the deflection means 21 has to be set in the position 21A of FIG. 13A, so that the air can enter the envelope 12 and must pass through the means 20A In that case, the upper filtration mode (FS) is obtained, if the container 17 is arranged in the position shown in FIG. 12C, while the front filtration mode (FA) is obtained when the container 17 is arranged in the position shown in FIG. 12B. In order to illustrate the versatility of the invention, FIGS. 12A-D shows the same device already illustrated in FIGS. 12A-D, with the difference that now it has a substantially cylindrical shape. It is evident that a rotation of 180° of the device modifies the function exactly as in FIGS. 12A-D, with the advantage that the rotation of an element being of cylindrical shape can be realized by means of a suitable command means provided by the hood, for example a sprints knob, having a suitable mechanism, for changing the position of the cylindrical container 12' without any intervention within the hood.
FIGS. 12J-L shows instead how the same functioning way of FIGS. 10, 11, 12 and 13 could be obtained, according to another embodiment of the flow deflection device according to the invention, not by rotating the container 17", but overturning it. It can be furthermore noticed that, in the illustrated embodiment of FIGS. 12J-L, the cover 19 is not necessary.
FIG. 14 shows how, in a preferred embodiment, the container 17" can be constituted by a cartridge, containing an activated-carbon filter 20A, having walls formed for example as in FIGS. 12B and C. Such a cartridge 17" is drawn and replaced when the activated-carbon has lost its filtration efficacy. In FIG. 15, instead, the container 17", at the middle axis, has a hollow 22 wherein the activated-carbon filter 20A or any other air treatment means that has to be withdrawn once exhausted, is inserted.
Apparently, it can seem complicated to entrust the user with the task of orienting the container 17 or 17", or the frame 17', in the correct way. However, on the contrary, from FIGS. 16A and b, to this purpose it is sufficient to mark the end of the relevant faces with suitable duly oriented symbols. For example said container 17 is shown according to the positions shown in FIGS. 5B and 5D, and the symbols FA, FS, AP, AS, have been used, which are the initials, in the Italian language, of the previously described operating mode (front filtering, upper filtering, rear suction, upper suction).
It is evident from the given description how the present invention introduces important improvements in the functioning of hoods.
According to the invention, it is in fact possible to eliminate the activated-carbon filter from the scroll inlet, thereby freeing some space for uniform circulation of the air between the grease filter and the nosepiece of the fan, and also reducing the height of the hood. The arrangement of the filtering means downstream of the scroll, according to the present teachings, does not require additional space, but instead it better utilizes the existing one. It simplifies the conduits downstream of the scroll and finally allows the use of filters having an effective passage section, of the desired dimensions, being limited only by the external dimensions of the hood. On the contrary, it has been seen that in a filter, even being very wide, mounted on the nosepiece, the zone effectively crossed by the air is limited to the area of the nosepiece.
The described invention is susceptible of several modifications and variations, which fall within the inventive idea. It is clear that all the described details and constructive materials can be changed with others which are technically equivalent. The practical examples herein illustrated are only some of the possible ones. | The invention relates to a hood for the suction and/or the filtration of cooking smokes in a domestic kitchen, having means which allows one, in a simple and rapid way, to direct the air flow sucked from a cooking stove towards a preferred outlet, among a plurality of possible outlets being provided by the hood, and to simultaneously change the operation of the hood from a filtration mode to a suction mode. | 5 |
BACKGROUND OF THE INVENTION
This invention relates to a novel sewing machine attachment and, particularly, to an attachment for holding an accessory, such as a hook or an eye, in a predetermined position for sewing. The sewing machine or stitch-forming machine used for the novel attachment hereinafter described is of the type generally used to secure buttons, hooks or other fasteners to fabric or other pliable web material.
U.S. Pat. No. 3,143,092 issued Aug. 4, 1964 to A. Glassman et al discloses a sewing machine attachment for use in locating and holding a magnetizable accessory in a predetermined position for sewing on a sewing machine. That attachment comprises generally (a) a substantially horizontally-extending positioning member having an open cavity therein wherein at least a portion of the walls of the cavity defines a seat for an accessory and (b) magnetic means within the positioning member for producing a magnetic flux which extends from said seat through the opening in the cavity. U.S. Pat. No. 3,415,210 issued Dec. 10, 1968 to A. Glassman discloses another such sewing-machine attachment.
Previously, the horizontally-extending positioning member was made by milling out a deep groove in a block of brass or other nonmagnetic material and then soldering a plate to the block thereby forming the cavity in which the plate is the bottom major wall of the cavity. In use, the plate is the most frequent site of failures. For example, while sewing, when the needle strays from its normal path of travel, it often strikes the accessory whereby it pushes down causing the solder joint to rupture and the plate to burst away from the attachment.
Another problem with the prior attachment is that dust and foreign particles accumulate in the cavity and are compacted at the back of the cavity adjacent the source of magnetic flux. The compacted debris interferes with the operation of the attachment and often prevents the accessory from seating properly. The prior attachment is provided with a clean-out hole which can be used for removing the debris from the cavity by poking with a wire or other elongated object. While this procedure provides some relief, it is time consuming and is not practiced frequently enough, so that the problem persists and hampers the effective usage of the attachment.
SUMMARY OF THE INVENTION
The novel attachment, as in prior attachments, comprises a substantially horizontally-extending positioning member having (a) an open cavity therein, at least a portion of the cavity walls defining a seat for a magnetizable accessory, and (b) magnetic means within the positioning member for producing a magnetic flux which extends for the seat through the opening of the cavity. Unlike prior attachments, at least a portion of one wall of the cavity is removably mounted (instead of fixedly mounted) on the positioning member. In a preferred form of the attachment, the cavity is defined by two major horizontally-extending walls. At least a portion of one of the major walls, preferably the bottom major wall, is a plate that is removably mounted on the positioning member. The plate may be rectangular with two opposite sides that are angularly shaped to a dovetail and are adapted to mate with dovetailed slots in the positioning member. To improve the fit of the plate in the slots without increasing the mechanical stress in the walls defining the slots, it is desirable to provide a slit aperture in the plate closely spaced from and substantially parallel to one of the angularly-shaped sides.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a perspective view of a preferred embodiment of the novel attachment adapted for positioning either a hook or an eye.
FIG. 2 is a sectional elevational view of the embodiment of FIG. 1 in position prior to stitching a hook to fabric.
FIG. 3 is a bottom view of the embodiment of FIG. 1 showing the dovetailed plate positioned so that the cavity is partially opened.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIGS. 1, 2 and 3 illustrate a preferred embodiment of the invention. The embodiment is a unitary structure having an L shape with an overall height (vertical dimension) of about 1.25 inches, an overall length (horizontal dimension) of about 1.25 inches, and a width of about 0.75 inch. All of the portions of the attachment are of a nonmagnetic material such as brass, copper, plastic or ceramic, except as otherwise indicated.
A vertically-extending shank portion 21 of the embodiment is about 0.25 inch long (horizontal dimension) and has a vertical slot 23 therein extending downward from the upper end thereof for attaching the shank portion 21 to a stationary portion 29 on a sewing machine as shown in FIG. 2. For attachment, the shank portion 21 is slipped under a screw head 25 of a screw 27 in the slot 23, the attachment is positioned as desired, and the screw 27 tightened.
The horizontally-extending positioning portion 31, also referred to as the foot of the embodiment, is about 0.31 inch high and about 1.25 inches long (horizontal dimension). The positioning portion or foot 31 is attached to the lower end of the shank portion 21 and is preferably integral with the shank portion 21. The other extended end 33 of the positioning portion 31 has an open definitely-shaped cavity 35 therein adapted to receive either a hook or an eye of the type which has a pair of adjacent eyelets at one end thereof through which the thread passes for stitching the hook or eye to fabric. The opening to the cavity 35 is formed in part by two opposed curved or arcuate surfaces 37 arranged to receive the outer opposed curved surfaces of the eyelets of an accessory such as a hook or an eye. The extended end of the foot 31 curves inwardly so that the foot 31 is clear of the stitching needle 69 and of the stitches formed by the sewing machine. The adjacent eyelets extend beyond the cavity and under the stitching needle 69.
The cavity includes also a first pair of parallel spaced vertical walls 39, a horizontal floor 41, and a first horizontal roof 43 extending inwardly of the foot 31 adapting the foot 31 to receive the hook portion 75 of the hook 71 as illustrated in FIG. 2. The cavity 35 includes also a second pair of parallel spaced vertical walls 45, the horizontal floor 41, and a second horizontal roof 47 extending inwardly of the foot 31 adapting the foot 31 to receive the eye portion 73 of an eye (not shown).
A small cylindrical permanent magnet 51 is fixed within the foot 31 and axially aligned with the cavity 35 and extends from the most inward portion of the cavity 35 to the end of the foot 31 which joins the shank 21. The magnet 51 may be positioned in the foot by pressing it into a small cylindrical hole bored in the desired position for that purpose. The magnet may be held in the hole by a press-fit, by adhesive, or by other suitable arrangement. The magnet 51 is magnetized so that a magnetic field (also referred to as magnetic flux) extends through the opening to the cavity 35. The magnet 51 may be magnetized either before or after insertion into the foot 31. The magnet 51 may be of any of the known permanent magnet materials, but is preferably of an aluminum-nickel-cobalt alloy, generally known as alnico.
The foot 31 also may have a transverse hole (not shown) extending across the width of the foot 31 at the most inward portion of the cavity 35. It has been found that dust, lint, and other fine material tend to accumulate at the most inward portion of the cavity at the end of the magnet 51. The hole provides an access through which this undesirable material may be removed, as by blowing with air.
A portion of the horizontal floor 41 of this embodiment of the novel attachment is a rectangular plate 57 which is removably mounted or detachably mounted on the horizontally-extending positioning member 31. This mounting is to be compared with the prior attachments mentioned above in which the horizontal floor and bottom wall of the cavity 35 is integral with or fixedly mounted to the positioning member 31. As shown in FIGS. 1, 2 and 3, the plate 57 has two opposite sides 59 that are angularly shaped to a dovetail. Also, the bottom of the positioning member 31 has two opposed slots 61 therein that are adapted for mating with the dovetailed sides 59 of the plate 57. As shown, the plate 57 is introduced into the slots 59 from the side of the attachment and slid into place, thereby providing the bottom wall and floor of the cavity. If it is desired to clean out debris from the cavity, the plate 57 may be slid partially or completely out of the slots 59, and any debris therein can be removed since the cavity is now easily accessible for cleaning. When cleaning is completed, the plate 57 is slid back into place.
It is desirable to provide a slit aperture 63 that extends through the plate 57. The slit aperture 63 is closely spaced from and parallel to one of the opposite angularly-shaped sides 59 of the plate 57. The slit aperture 63 which is about 4 mm (10 mils) wide defines a band 65 of plate material which provides a spring effect into the plate 57. This spring effect allows a wider tolerance in the width of the plate 57 while still providing adequate pressure on the dovetailed slots 61 to keep the plate 57 securely in place.
In operation, the shank portion 21 is positioned and attached to the stationary portion of a sewing machine below the needle 69 as previously described. A hook 71 (or an eye) is held close to the open end of the cavity 35 in the desired orientation. The magnetic flux, which extends from the magnet 51 through the open end of the cavity 35, draws the hook 71 (or an eye) into the cavity 35 and holds it therein with the outer opposed curved surfaces of the eyelets 73 bearing against the arcuate spaced walls 37 of the cavity 35. A piece of fabric 63 is positioned on a table 65 below the needle 61. The attachment is now moved downwardly so that the bottom of the foot 31 rests on the fabric 67. The needle 61 now stitches the hook 71 (or the eye) to the fabric 67 by alternate motion into each eyelet 73. The attachment is now moved upwardly and the fabric 63 with the hook 79 (or the eye) stitched thereto is removed and the process repeated.
The horizontally-extending foot portion 31 and the shank portion 21 may be perpendicular to one another. It has been found advantageous, however, to make the angle therebetween slightly greater than 90°, preferably about 100°, so that the extended end 33 of the foot 31 toes slightly downward. It is further advantageous to bevel the bottom of the foot 31 so that the bottom portion 55 near the extended end 33 is perpendicular to the shank 21. The downward toe and the bevel 55 of the foot 31 brings the eyelets 73 closer to the fabric 67 producing a tighter stitching thereto.
The novel attachment does not require the insertion of the hook (or the eye) into the cavity 35 by pressure. Furthermore, there are no moving parts therein to require servicing or adjustment. The actual insertion and positioning of the hook 71 (or eye) with respect to the stitching needle 61 is done by the magnetic attraction of the magnetic field from the magnet for the hook 71 (or the eye).
One additional problem of prior attachments that is avoided by the novel attachment is the adverse effect of the needle 69 straying from its prescribed path. Occasionally when the needle 60 strayed, and struck the hook 71 (or eye), it pushed down, causing the bottom wall, which was fixedly attached, to burst away from the positioning member 31. Since that portion of the bottom wall is not present in the novel attachment, this cannot happen. With the novel attachment, the needle will deflect from the eyelet 73 before damage can occur. This extends the average life of the attachment.
The novel attachment may include a finger that is pivotally mounted on the foot similar to the structure described in U.S. Pat. No. 3,415,210 to A. Glassman. | Sewing machine attachment comprises a substantially horizontally extending positioning member having an open cavity therein, at least a portion of the cavity walls defining a seat for a magnetizable accessory and magnetic means within the positioning member for producing a magnetic flux which extends from the seat through the opening to the cavity for attracting the accessory. At least a portion of one wall of the cavity, preferably the bottom wall, is removably mounted on the positioning member. | 3 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to U.S. Provisional Patent Application No. 62/111,560, filed Feb. 3, 2015 and entitled “DETECTING FRAUD DRIVEN BY HTML-MODIFYING MALWARE,” the content of which is incorporated by reference in its entirety.
BACKGROUND
[0002] As the use of computing devices, software, and the Internet expands, threats from Malicious software, also referred to as “malware,” increases as well. Such malware can be used, for example, to take control of some or all of a computing device's functionality, to collect otherwise-sensitive or private information, and to spread malware to other devices. Malware can thus be used in conjunction with criminal activities such as fraud (e.g., identity theft), corporate espionage, and other illicit activities.
[0003] One form of malware, HTML-modifying malware, performs illicit modifications to web pages. Embodiments of the present disclosure help detect such modifications, as well as addressing other issues.
SUMMARY
[0004] Among other things, embodiments of the present disclosure help provide entities with the ability to remotely detect behavior associated with malware and identify compromised user-sessions, regardless of the malware variant or family, and independently of the page structure.
[0005] Exemplary embodiments of the present disclosure include a server that hosts a web page and is configured to determine if the page displayed by a remote web browser contains malware-related modifications. Additionally, if a malicious modifying-element is found, embodiments of the disclosure can create an accurate representation of the modified page in order to support forensic processes and impact mitigation procedures.
[0006] A computer-implemented method according to various aspects of the present disclosure includes: transmitting, by a server computing device to a client computing device over a network, a code module for collecting and transmitting data related to a web page presented on the client computing device; receiving, by the server computing device, the data related to the web page presented on the client computing device, wherein the data related to the web page is received over the network via the code module operating on the client computing device; analyzing, by the server computing device, the data related to the web page, wherein analyzing the data related to the web page includes comparing the data to one or more of: one or more patterns associated with non-modified web page states; one or more patterns associated with malicious web page states; and one or more patterns associated with innocuous web page modifications; and in response to the analysis, generating a risk factor associated with the web page.
[0007] The present disclosure includes various methods, apparatuses (including computer systems) that perform such methods, and computer readable media containing instructions that, when executed by computing systems, cause the computing systems to perform such methods.
[0008] Other features will be apparent from the accompanying drawings and from the detailed description which follows.
BRIEF DESCRIPTION OF DRAWINGS
[0009] FIG. 1 is an exemplary method according to various aspects of the present disclosure.
[0010] FIG. 2 is a graphical illustration showing how HTML from a web page may be scanned by a code module and translated into a set of data according to various aspects of this disclosure.
[0011] FIGS. 3 and 4 are graphical illustrations of pattern matching according to various aspects of this disclosure.
[0012] FIG. 5 is an exemplary risk assessment graph according to various aspects of the present disclosure.
[0013] FIG. 6 is a block diagram of an exemplary system according to various aspects of the present disclosure.
DETAILED DESCRIPTION
[0014] Subject matter will now be described more fully hereinafter with reference to the accompanying drawings, which form a part hereof, and which show, by way of illustration, specific example embodiments. Subject matter may, however, be embodied in a variety of different forms and, therefore, covered or claimed subject matter is intended to be construed as not being limited to any example embodiments set forth herein; example embodiments are provided merely to be illustrative. Likewise, a reasonably broad scope for claimed or covered subject matter is intended. Among other things, for example, subject matter may be embodied as methods, devices, components, or systems. Accordingly, embodiments may, for example, take the form of hardware, software, firmware or any combination thereof (other than software per se). The following detailed description is, therefore, not intended to be taken in a limiting sense.
[0015] In the accompanying drawings, some features may be exaggerated to show details of particular components (and any size, material and similar details shown in the figures are intended to be illustrative and not restrictive). Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the disclosed embodiments.
[0016] Reference in this specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the disclosure. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Moreover, various features are described which may be exhibited by some embodiments and not by others. Similarly, various requirements are described which may be requirements for some embodiments but not other embodiments.
[0017] Any combination and/or subset of the elements of the methods depicted herein may be combined with each other, selectively performed or not performed based on various conditions, repeated any desired number of times, and practiced in any suitable order and in conjunction with any suitable system, device, and/or process. The methods described and depicted herein can be implemented in any suitable manner, such as through software operating on one or more computer systems. The software may comprise computer-readable instructions stored in a tangible computer-readable medium (such as the memory of a computer system) and can be executed by one or more processors to perform the methods of various embodiments.
[0018] FIG. 1 illustrates an exemplary method according to various aspects of the present disclosure. The steps of method 100 may be performed by any suitable computing device, such as by server computing device 610 depicted in FIG. 6 . In this example, method 100 includes generating one or more patterns associated with web pages ( 105 ), configuring a code module for collecting and transmitting data related to a web page ( 110 ), transmitting the code module to a client computing device ( 115 ), receiving web page data from the code module ( 120 ), analyzing the web page data ( 125 ), generating a risk factor based on the analysis ( 130 ), generating one or more alerts ( 135 ), and updating one or more patterns associated with web pages ( 140 ).
[0019] Embodiments of the present disclosure may generate ( 105 ) a variety of different patterns associated with various web page states to help identify a malicious (or potentially malicious) modification to a web page.
[0020] In one exemplary embodiment, the remote access server (RAS) apparatus includes three static knowledge bases and a dynamic risk-assessment algorithm. Other knowledge bases and algorithms may also be utilized in conjunction with embodiments of the present disclosure. In this example, the static knowledge bases include a “known-to-be-good” list, a “known-to-be-malicious” list and a “known-to-be-innocuous” list. These lists are discussed in more detail with reference to analyzing the web page data (step 125 ).
[0021] In some exemplary embodiments, the static knowledge bases may be configured during a training/setup phase. In some cases, the system may assume that a site to be protected is being browsed only from secured stations, and hence it can put into the “known-to-be-good” list all the unknown states coming from the code module. To avoid problems with this assumption, some training machines may be configured to send specially crafted hypertext transfer protocol (HTTP) headers when browsing the protected portal. In Addition to such headers, the RAS may also have a list of IP addresses where training machines can communicate from. This way, if an unknown state arrives to the RAS and the state-report contains the adequate HTTP headers and comes from the expected IP address, the RAS includes this new state into the “known-to-be-good” list.
[0022] During operation, when a session that has been identified as potentially risky (e.g., by the system, operator, third party actor, etc.), the system may classify the page as described in more detail below (e.g., “Page OK,” “Page Modified by a Malicious Element,” “Page Modified by an Inoffensive Element”). The system can then generate a pattern associated with each type of classification in the static knowledge bases. This enables the system to accurately identify the next session that matches the new pattern, independently of the list where it was finally inserted. Additionally, in order to improve its accuracy, the “risk assessment algorithm” can be trained periodically including all the data contained in the lists.
[0023] A code module may be configured ( 110 ) and transmitted ( 115 ) to a client computing device to collect data related to a web page presented on the computing device. In some exemplary embodiments, a web server may automatically configure a code module comprising a set of code (e.g, written in JAVASCRIPT or another language), embed the code module in a Hypertext Markup Language (HTML) web page, and provide the web page and code module to the client computing device, in response, for example, to a user of the client computing device visiting a web portal hosted by the web server.
[0024] In other embodiments, the code module may be embedded into a web page by a server or other computing device other than the web server. For example, a loader module comprising a small snippet of code may be inserted into the web page by the web server hosting the web page or another device. The loader module may perform various configuration actions (such as setting page-identifier variables), loads the code module from a server (e.g., possibly a different server from the web server), and embeds the code module in the web page.
[0025] The code module is configured to collect data related to the web page to be used in the detection of malware-related modifications. In one embodiment, the code module waits until the page if fully rendered by the browser before starting collection of the data.
[0026] FIG. 2 illustrates how a portion of HTML from a web page may be scanned by the code module and translated into a set of data (in a data structure) that can be converted to JSON or any other exchanging data format and sent to the RAS.
[0027] Embodiments of the present disclosure may be configured to collect information about specific elements. Those elements may be chosen according to the kind of attacks the system seeks to detect and address. For example, if the system is focused on preventing HTML injections intended to steal credentials or sensible data (as shown in FIG. 2 ), the system collects information on elements that can potentially be used to ask the user for additional data such inputs, text fields or any kind editable element. Additionally, in order to have a better insight of the current page structure, embodiments of the disclosure may include all the elements that act as containers of the editing elements found in the page. In the example shown in FIG. 2 , a form containing three input elements is mapped to a representation in the form of a tree structure containing the details of input fields nested inside the details of a form element. Similarly, an embodiment seeking to detect the addition of data intended to modify the page structure dynamically, can include script (e.g., JAVASCRIPT) tags to the set of collected elements. Any set of elements may be selected for monitoring based on any desired criteria, and such elements being monitored may be dynamically modified during the operation of the system.
[0028] In various embodiments, as shown in FIG. 2 , a set of data related to a web page is collected by the code module and transmitted to a Risk Analysis Server (RAS), where further verifications are performed in order to determine the presence of malware-related modifications. The functionality of the RAS may be performed by the server computing device 610 depicted in FIG. 6 , as well as by other suitable computing devices in communication with the client computing device upon which the code module is running
[0029] Any desired web page data may be collected by the code module. For example, the code module may be configured to collect data on any feature of the web page that can potentially be used to modify the page structure, and consequently, to potentially lure the user of the client computing device to disclose sensitive information that would not have been asked for by the unmodified web page. Data related to the web page collected by the code module may include, for example, one or more: identifiers, styling details, nesting details, locations of features within the web page (e.g.,inside the HTML tree), elements that request a user of the client computing device to enter data, and/or script elements (e.g., in JAVASCRIPT).
[0030] The data related to the web page is received ( 120 ) from the code module by the RAS or another system implementing the functionality of the embodiments of the present disclosure, and such data may be transmitted to the RAS in any desired manner. For example, the data related to the web page may be packaged as a JAVASCRIPT Object Notation (JSON) document (or any other exchanging data format).
[0031] Embodiments of the present disclosure can collect data related to the web page that enables the RAS to get full insight of the actual state of the web page by, for example, detailing Document Object Model (DOM) elements, the structure of the web page, and the content of any scripts operating on the web page, without having to send the entire HTML document implementing the web page. Among other things, including only a subset of the total elements present in the web page (e.g., those most useful in identifying malicious modifications to the page) helps avoid network overload and helps keep the responsiveness of the web-portal relatively unaffected by the embodiments of this disclosure. This latter feature also helps embodiments of the present disclosure provide effective protection while keeping the user experience relatively unaltered.
[0032] The web page data may be analyzed ( 125 ) to identify known patterns in the web page data that are known to be indicative of non-modified states, malicious modifications, innocuous modifications, or other cases. Continuing the example described above with reference to step 105 , embodiments of the present disclosure may compare the data associated with the web page to various lists of patterns, such as the “known-to-be-good” list, “known-to-be-malicious” list and “known-to-be-innocuous” list introduced above.
[0033] The known-to-be-good list holds a set of patterns associated with states of the page identified as not modified states. This set of states may be learned by the system during the training phase and along the operation lifecycle. Feature sets of data related to a web page may be analyzed using different lists of patterns in any desired manner In one exemplary embodiment, a feature-set may first be analyzed against the “known-to-be-good” list in order to check if it matches with any of the stored states. If a match is found, the session is marked as not risky and no further analysis is performed. If at least one feature in the data is not on the “known-to-be-good” list, however, further analysis may be performed.
[0034] The “known-to-be-malicious list” contains a set of patterns that constitutes the base of known attacks that the system learns through its operational lifecycle. The patterns contained in this list provide the system with the capability to quickly identify already known attacks and classify them as associated with a specific malware variant or campaign. If a feature-set contained in web page data collected by the code module is found to match a pattern contained in this list, the web page may be automatically marked as risky and no further analysis performed. Alternatively, the system may engage in additional analysis to, for example, identify additional threats in the page, the possible source of one or more threats, and other information. Among other things, such additional analysis may be used to better update the pattern lists of the embodiments of the present disclosure, as well as to provide useful information to web hosts and law enforcement regarding malicious web page modifications the system detects.
[0035] The “known-to-be-innocuous” list may be used to identify patterns that indicate a web page has been modified, but not in a manner that is malicious. Such modifications may include, for example, browser plugins that modify the page DOM to include a graphical user interface (GUI) but do not pose a threat. In some exemplary embodiments, the RAS attempts to determine if the analyzed features have content matching any pattern in the “known-to-be-innocuous” list. If a match is found, then the RAS checks whether, after removing the matching content from the features, there is a close matching with at least one of the entries from the known-to-be-good list. If this latter test ends with a match, the session may be marked as safe and no further analysis is needed. Otherwise, the system may perform a risk-assessment algorithm, as described in more detail below. In some embodiments, a risk-assessment algorithm is only performed in response to a determination, by analyzing the data related to the web page, that one or more elements in the web page data do not correspond to any pattern in at least of the static lists available to the system. Among other things, this allows the system to identify potentially new patterns that can be added to the static lists.
[0036] Embodiments of the present disclosure may perform any desired analysis in order to identify patterns of groups of elements, and structures inside the compared element features, within the data related to a web page. The representation of such patterns may be diverse, and utilize (for example) a variety of XML pattern matching techniques, such as XPATH.
[0037] The patterns contained in the static knowledge bases described previously may comprise data structures which may be similar to the data structures collected by the code module on the client computing device. The data structures may provide a simplified version of a page features document, which include a subset of the elements and details of particular interest for the given list.
[0038] When looking for a match, if the compared feature set contains all the elements and structure detailed in the pattern, it may be said that it matches the pattern, even if the compared feature contains more elements than the matched pattern. FIG. 3 illustrates a graphical example of a match against a pattern. In this example, the pattern (in the left box) is found in the data retrieved from the web page (in the right box). FIG. 4 , by contrast, illustrates an example where no match is found, as the lower portion of the pattern in the left box is not present in the data retrieved from the web page (right box).
[0039] In some embodiments, the analysis of the web page data ( 125 ) may conclude in response to correlating the web page data with patterns in the static lists. If such analysis does not produce a conclusive result (e.g., because one or more elements in the web page data are not found in any of the lists), additional analysis may be performed in order to determine whether the web page has (or is at risk of having) a malicious modification. In some exemplary embodiments, the features in the web page data can be further analyzed using a risk-assessment algorithm in order to generate a risk factor ( 130 ). In various embodiments, the risk-assessment algorithm may be automatically adjusted based on the history of incidents related to HTML-modifying malware detected by the system. In this manner, embodiments of the present disclosure automatically improve their effectiveness of the system and learn from previously-detected threats without necessitating user intervention to identify such threats.
[0040] In some embodiments, the factors that determine the risk-level of a given feature-set may be dictated by the history of the system. For example, the more malware-related modifying-elements the features include, the higher the risk assigned to the session. In order to assets the risk-level of a session, a risk factor map maybe defined so that sessions with risk-level below a given safe-level are discarded as not risky, and risk-levels above a trigger value are automatically marked as risky, as shown in the graph in FIG. 5 .
[0041] In this example, when the risk-level is not below or above the given limits in the graph, the session may be marked as potentially risky and external intervention may be required in order to conclude the nature of the modification performed to the web page. Once the riskiness of the session has been determined, that feedback may be included to the system's knowledge base and used by all future analyses of web page data.
[0042] In various embodiments, the risk assessment algorithm may comprise a prediction algorithm implementing a function that discriminates between risky and not risky modifications, giving as an output a number indicating the probability that a given feature-set contains harmful modifications.
[0043] In various embodiments, the risk assessment algorithm is updated to reflect the system history. That is, it is re-parameterized periodically such that its final output assigns a greater riskiness to those page-modifications containing elements or variations typically included in malware modifications found over the system history.
[0044] As an illustrative example, consider that for a given page the system has positively identified a set of malware injections in the following HTML code, with the bold-face sections being indicators of fields added to the original structure:
[0000]
...
<form name=“login” action=“https://services.location/path”
method=“post”>
...
<label for=“atm
—
pin ”>ATM Pin</label>
<input id=“ atm
—
pin ” type=“password”>
...
</form>
...
<form name=“otp
—
sync”
action=“https://services.location/fakepath” method=“post”>
...
<label for=“ otp
—
number ”>OTP Number</label>
<input id=“ otp
—
number ” type=“text”>
...
</form>
...
<form name=“login” action=“https://services.location/path”
method=“post”>
...
<label for=“creditcard ”>ATM Pin</label>
<input id=“creditcard” type=“text”>
<label for=“cvc ”>CVC Number</label>
<input id=“cvc” type=“password”>
...
</form>
[0045] In some cases, for a feature-set which difference with its closest known-to-be-good pattern includes elements of type input, chances are that such page is being modified by a malicious agent. Furthermore, if the difference includes not only input elements but input elements with type password, the likelihood of being a malicious will be much higher than the previous situation.
[0046] Deciding the kind of observed variables to include as input for the classification algorithm can be obtained by empirical observation, as well as by using exploratory data analysis techniques. Once a determination is made as to the variables to observe when trying to determine the riskiness of a page, a determination is made as to the set of parameters that better fit for the chosen algorithm or function.
[0047] Some embodiments may include the content of the known-to-be-innocuous list, so that elements or variations typically included both in malicious and innocuous modifications trigger a lower risk-level than those included exclusively in malicious modifications.
[0048] As an example, an embodiment of the present disclosure may use the following sigmoid function as a prediction function:
[0000]
y
(
v
)
=
1
1
+
-
v
[0000] Where v is the weighted sum of the difference of the observed variables between the analyzed page-feature and its closest pattern.
[0000]
v
=
∑
j
w
j
V
j
[0000] Where V j is the number of occurrences of each one of the observed variables.
[0049] The risk assessment algorithm may be tuned to fit the history of web page data analyzed by the system by finding the combination of w j that gives the best prediction.
[0050] Whenever as session is marked as risky or potentially risky, the code module may be instructed (e.g, by the RAS) to create a full snapshot of the state of the page so that it can be used to create an accurate representation of the page status. Such snapshot is intended to be used as visual evidence in forensic processes as well as to support the determination of the level of risk of a modification.
[0051] In one embodiment, when the code module creates the snapshot, it copies the entire HTML of the page and posts it to the RAS. The RAS in turn saves the HTML content and converts the page into an image that shows the visual aspects of the page.
[0052] In one exemplary embodiment, a script module is commanded by the RAS to take a snapshot of the page by making a copy of the current document object model (DOM) tree. The DOM copy is then prepared to be sent to the server by converting all the relative resources (URLs) to its absolute representation. If the page contains HTML “IFRAME” or “FRAME” elements and the cross-origin policies allow it, its content is also copied and prepared. The prepared data is sent to the RAS which finally queues it to be rendered by the rendering engine. The rendering engine is a headless (no GUI) browser which is used to render the DOM sent by the monitoring script. The output of the render engine is then stored and associated to the data of the incident so that the operator can see it when reviewing incident reports. The DOM sent by the monitoring script is also stored so that it can be used in forensic procedures to identify the portions of HTML injected by malware.
[0053] Embodiments of the present disclosure may generate various alerts ( 135 ) such as by posting usage reports and incident events whenever a risk has been found. Such reports and events can be used by an external agent/component to consolidate statistics and reports detailing the activity registered by the system. Additionally, incident reports can be used by the web portal owner in order to start mitigation procedures or to perform forensic operation.
[0054] In some cases, such as when a session is analyzed and its riskiness level is not conclusive, the session may be marked as potentially risky and an alert generated to a user of the system (or an external agent) to indicate additional analysis/intervention may be needed in order to help determine or evaluate the risk factor of the web page session.
[0055] Such alerts may be generated and provided to various users and systems in any suitable manner. For example, a human agent may be alerted with a notification that can be sent by any kind of communications method, such as an e-mail or a phone call to dedicated monitoring application. Once the agent decides to attend the incident, he/she may be presented with a set of elements/data intended to facilitate its work and guarantee the identification of any new attack campaign. Automated agents (e.g., controlled by software operating on other servers) may similarly be notified. Sets of elements provided to agents may include, for example:
Details of the Incident:
[0056] Such details may include some or all of the data that can be collected to determine when, where and how the incident happened. Such details may include, for example: URL, timestamp, remote IP Address, Browser Id/version, underlying OS, language, session id, incident id, detail of the headers used by the browser, etc.
Snapshot:
[0057] The snapshot, such as described previously, offers the agent the opportunity to view an accurate image of what the user of the client computing device was watching on his/her browser when the incident was detected. As stated previously, when an incident is found, the code module may be instructed to send all the data available that allows the system to build a good approximation of what is visible for the user in that precise instant. Among other things, this helps the agent to appreciate the visual differences between the modified and the original page.
HTML Content:
[0058] The same data used to generate the snapshot of the incident may also be made available to the agent so that he/she can examine in detail the elements that where altered on the page.
[0059] Once the external agent has determined the nature of the incident, the agent can acknowledge the system in various ways. The agent can also identify new patterns in order to update one or more patterns ( 140 ) in the static lists. Alternatively or in conjunction, embodiments of the present disclosure may also add new patterns to the static lists. Acknowledgements provided by an agent may include, for example:
Page OK:
[0060] This selection may be made when the agent determines that the session didn't contain any kind of modification. This may occur, for example, when the portal owner introduces changes to the protected page and the system hasn't yet encountered this new version of the page before. In this case, the system simply could add one or more patterns reflecting this new state to the known-to-be-good list.
Page Modified by a Malicious Element:
[0061] In this case, the agent determines that the page has been actually modified with malicious purposes. Together with this acknowledgment, the agent may provide a label identifying the modification. This label can be an identifier of the malware performing the injection, the name of the attack or any other meaningful text. The system may proceed to determine the modifying elements and to create a pattern to be included in the known-to-be-malicious list so that a match can be found in this list the next time the system analyzes data from a web page is being injected by the same malicious actor.
Page Modified by an Inoffensive Element:
[0062] In this case, the agent determines that the page has been modified, but the modification is not malicious. This may occur, for example, when the browser includes extensions/plugins intended to improve the user experience or to provide additional services while the user is browsing. The extracted pattern may be added to the known-to-be-innocuous list for future analyses.
[0063] In some embodiments, intervention by an external agent (whether human or another system) is logged so that the source of modifications to the static lists or risk analysis algorithm(s) can be traced.
[0064] FIG. 6 is a block diagram of system which may be used in conjunction with various embodiments. While FIG. 6 illustrates various components of a computer system, it is not intended to represent any particular architecture or manner of interconnecting the components. Other systems that have fewer or more components may also be used.
[0065] In FIG. 6 , the system 600 includes a server computing system 610 comprising a processor 612 , memory 614 , and user interface 616 . Computer system 610 may include any number of different processors, memory components, and user interface components, and may interact with any other desired systems and devices in conjunction with embodiments of the present disclosure.
[0066] The functionality of the computer system 610 , including the steps of the methods described above (in whole or in part), may be implemented through the processor 612 executing computer-readable instructions stored in the memory 614 of the system 610 . The memory 614 may store any computer-readable instructions and data, including software applications, applets, and embedded operating code. Portions of the functionality of the methods described herein may also be performed via software operating on one or more of the user computing devices 620 .
[0067] The functionality of the system 610 or other system and devices operating in conjunction with embodiments of the present disclosure may also be implemented through various hardware components storing machine-readable instructions, such as application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs) and/or complex programmable logic devices (CPLDs). Systems according to aspects of certain embodiments may operate in conjunction with any desired combination of software and/or hardware components. The processor 612 retrieves and executes instructions stored in the memory 614 to control the operation of the system 610 . Any type of processor, such as an integrated circuit microprocessor, microcontroller, and/or digital signal processor (DSP), can be used in conjunction with embodiments of the present disclosure. A memory 614 operating in conjunction with embodiments of the disclosure may include any combination of different memory storage devices, such as hard drives, random access memory (RAM), read only memory (ROM), FLASH memory, or any other type of volatile and/or nonvolatile memory. Data can be stored in the memory 614 in any desired manner, such as in a relational database.
[0068] The system 610 includes a user interface 616 that may include any number of input devices (not shown) to receive commands, data, and other suitable input. The user interface 616 may also include any number of output devices (not shown) to provides the user with data, alerts/notifications, and other information. Typical I/O devices may include mice, keyboards, modems, network interfaces, printers, scanners, video cameras and other devices.
[0069] The system 610 may communicate with one or more client computing devices 620 , as well as other systems and devices in any desired manner, including via network 630 . The system 610 and/or client computing devices 620 may be, include, or operate in conjunction with, a laptop computer, a desktop computer, a mobile subscriber communication device, a mobile phone, a personal digital assistant (PDA), a tablet computer, an electronic book or book reader, a digital camera, a video camera, a video game console, and/or any other suitable computing device.
[0070] The network 630 may include any electronic communications system or method. Communication among components operating in conjunction with embodiments of the present disclosure may be performed using any suitable communication method, such as, for example, a telephone network, an extranet, an intranet, the Internet, point of interaction device (point of sale device, personal digital assistant (e.g., iPhone®, Palm Pilot®, Blackberry®), cellular phone, kiosk, etc.), online communications, satellite communications, off-line communications, wireless communications, transponder communications, local area network (LAN), wide area network (WAN), virtual private network (VPN), networked or linked devices, keyboard, mouse and/or any suitable communication or data input modality. Systems and devices of the present disclosure may utilize TCP/IP communications protocols as well as IPX, Appletalk, IP-6, NetBIOS, OSI, any tunneling protocol (e.g. IPsec, SSH), or any number of existing or future protocols.
[0071] Communication among systems, devices, and components operating in conjunction with embodiments of the present disclosure may be performed using any suitable communication method, such as, for example, a telephone network, an extranet, an intranet, the Internet, point of interaction device (point of sale device, personal digital assistant (e.g., iPhone®, Palm Pilot®, Blackberry®), cellular phone, kiosk, etc.), online communications, satellite communications, off-line communications, wireless communications, transponder communications, local area network (LAN), wide area network (WAN), virtual private network (VPN), networked or linked devices, keyboard, mouse and/or any suitable communication or data input modality. Systems and devices of the present disclosure may utilize TCP/IP communications protocols as well as IPX, Appletalk, IP-6, NetBIOS, OSI, any tunneling protocol (e.g. IPsec, SSH), or any number of existing or future protocols.
[0072] While some embodiments can be implemented in fully functioning computers and computer systems, various embodiments are capable of being distributed as a computing product in a variety of forms and are capable of being applied regardless of the particular type of machine or computer-readable media used to actually effect the distribution.
[0073] A machine readable medium can be used to store software and data which when executed by a data processing system causes the system to perform various methods. The executable software and data may be stored in various places including for example ROM, volatile RAM, non-volatile memory and/or cache. Portions of this software and/or data may be stored in any one of these storage devices. Further, the data and instructions can be obtained from centralized servers or peer to peer networks. Different portions of the data and instructions can be obtained from different centralized servers and/or peer to peer networks at different times and in different communication sessions or in a same communication session. The data and instructions can be obtained in entirety prior to the execution of the applications. Alternatively, portions of the data and instructions can be obtained dynamically, just in time, when needed for execution. Thus, it is not required that the data and instructions be on a machine readable medium in entirety at a particular instance of time.
[0074] Examples of computer-readable media include but are not limited to recordable and non-recordable type media such as volatile and non-volatile memory devices, read only memory (ROM), random access memory (RAM), flash memory devices, floppy and other removable disks, magnetic disk storage media, optical storage media (e.g., Compact Disk Read-Only Memory (CD ROMS), Digital Versatile Disks (DVDs), etc.), among others. The computer-readable media may store the instructions.
[0075] In various embodiments, hardwired circuitry may be used in combination with software instructions to implement the techniques. Thus, the techniques are neither limited to any specific combination of hardware circuitry and software nor to any particular source for the instructions executed by the data processing system.
[0076] Although some of the drawings illustrate a number of operations in a particular order, operations which are not order dependent may be reordered and other operations may be combined or broken out. While some reordering or other groupings are specifically mentioned, others will be apparent to those of ordinary skill in the art and so do not present an exhaustive list of alternatives. Moreover, it should be recognized that the stages could be implemented in hardware, firmware, software or any combination thereof.
[0077] For the sake of brevity, conventional data networking, application development and other functional aspects of the systems (and components of the individual operating components of the systems) may not be described in detail herein. Furthermore, the connecting lines shown in the various figures contained herein are intended to represent exemplary functional relationships and/or physical couplings between the various elements. It should be noted that many alternative or additional functional relationships or physical connections may be present in a practical system.
[0078] The various system components discussed herein may include one or more of the following: a host server or other computing systems including a processor for processing digital data; a memory coupled to the processor for storing digital data; an input digitizer coupled to the processor for inputting digital data; an application program stored in the memory and accessible by the processor for directing processing of digital data by the processor; a display device coupled to the processor and memory for displaying information derived from digital data processed by the processor; and a plurality of databases. Various databases used herein may include: shipping data, package data, and/or any data useful in the operation of the system.
[0079] Various functionality may be performed via a web browser and/or application interfacing utilizing a web browser. Such browser applications may comprise Internet browsing software installed within a computing unit or a system to perform various functions. These computing units or systems may take the form of a computer or set of computers, and any type of computing device or systems may be used, including laptops, notebooks, tablets, hand held computers, personal digital assistants, set-top boxes, workstations, computer-servers, main frame computers, mini-computers, PC servers, network sets of computers, personal computers and tablet computers, such as iPads, iMACs, and MacBooks, kiosks, terminals, point of sale (POS) devices and/or terminals, televisions, or any other device capable of receiving data over a network. Various embodiments may utilize Microsoft Internet Explorer, Mozilla Firefox, Google Chrome, Apple Safari, Opera, or any other of the myriad software packages available for browsing the internet.
[0080] Various embodiments may operate in conjunction with any suitable operating system (e.g., Windows NT, 95/98/2000/CE/Mobile/, Windows 7/8, OS2, UNIX, Linux, Solaris, MacOS, PalmOS, etc.) as well as various conventional support software and drivers typically associated with computers. Various embodiments may include any suitable personal computer, network computer, workstation, personal digital assistant, cellular phone, smart phone, minicomputer, mainframe or the like. Embodiments may implement security protocols, such as Secure Sockets Layer (SSL), Transport Layer Security (TLS), and Secure Shell (SSH). Embodiments may implement any desired application layer protocol, including http, https, ftp, and sftp.
[0081] The various system components may be independently, separately or collectively suitably coupled to a network via data links which includes, for example, a connection to an Internet Service Provider (ISP) over the local loop as is typically used in connection with standard modem communication, cable modem, satellite networks, ISDN, Digital Subscriber Line (DSL), or various wireless communication methods. It is noted that embodiments of the present disclosure may operate in conjunction with any suitable type of network, such as an interactive television (ITV) network.
[0082] The system may be partially or fully implemented using cloud computing. “Cloud” or “Cloud computing” includes a model for enabling convenient, on-demand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, and services) that can be rapidly provisioned and released with minimal management effort or service provider interaction. Cloud computing may include location-independent computing, whereby shared servers provide resources, software, and data to computers and other devices on demand.
[0083] Various embodiments may be used in conjunction with web services, utility computing, pervasive and individualized computing, security and identity solutions, autonomic computing, cloud computing, commodity computing, mobility and wireless solutions, open source, biometrics, grid computing and/or mesh computing.
[0084] Any databases discussed herein may include relational, hierarchical, graphical, or object-oriented structure and/or any other database configurations. Moreover, the databases may be organized in any suitable manner, for example, as data tables or lookup tables. Each record may be a single file, a series of files, a linked series of data fields or any other data structure. Association of certain data may be accomplished through any desired data association technique such as those known or practiced in the art. For example, the association may be accomplished either manually or automatically.
[0085] Any databases, systems, devices, servers or other components of the system may be located at a single location or at multiple locations, wherein each database or system includes any of various suitable security features, such as firewalls, access codes, encryption, decryption, compression, decompression, and/or the like.
[0086] Encryption may be performed by way of any of the techniques now available in the art or which may become available—e.g., Twofish, RSA, El Gamal, Schorr signature, DSA, PGP, PKI, and symmetric and asymmetric cryptosystems.
[0087] Embodiments may connect to the Internet or an intranet using standard dial-up, cable, DSL or any other Internet protocol known in the art. Transactions may pass through a firewall in order to prevent unauthorized access from users of other networks.
[0088] The computers discussed herein may provide a suitable website or other Internet-based graphical user interface which is accessible by users. For example, the Microsoft Internet Information Server (IIS), Microsoft Transaction Server (MTS), and Microsoft SQL Server, may be used in conjunction with the Microsoft operating system, Microsoft NT web server software, a Microsoft SQL Server database system, and a Microsoft Commerce Server. Additionally, components such as Access or Microsoft SQL Server, Oracle, Sybase, Informix MySQL, Interbase, etc., may be used to provide an Active Data Object (ADO) compliant database management system. In another example, an Apache web server can be used in conjunction with a Linux operating system, a MySQL database, and the Perl, PHP, and/or Python programming languages.
[0089] Any of the communications, inputs, storage, databases or displays discussed herein may be facilitated through a website having web pages. The term “web page” as it is used herein is not meant to limit the type of documents and applications that might be used to interact with the user. For example, a typical website might include, in addition to standard HTML documents, various forms, Java applets, JavaScript, active server pages (ASP), common gateway interface scripts (CGI), extensible markup language (XML), dynamic HTML, cascading style sheets (CSS), AJAX (Asynchronous Javascript And XML), helper applications, plug-ins, and the like. A server may include a web service that receives a request from a web server, the request including a URL and an IP address. The web server retrieves the appropriate web pages and sends the data or applications for the web pages to the IP address. Web services are applications that are capable of interacting with other applications over a communications means, such as the Internet.
[0090] Various embodiments may employ any desired number of methods for displaying data within a browser-based document. For example, data may be represented as standard text or within a fixed list, scrollable list, drop-down list, editable text field, fixed text field, pop-up window, and the like. Likewise, embodiments may utilize any desired number of methods for modifying data in a web page such as, for example, free text entry using a keyboard, selection of menu items, check boxes, option boxes, and the like.
[0091] The exemplary systems and methods illustrated herein may be described in terms of functional block components, screen shots, optional selections and various processing steps. It should be appreciated that such functional blocks may be realized by any number of hardware and/or software components configured to perform the specified functions. For example, the system may employ various integrated circuit components, e.g., memory elements, processing elements, logic elements, look-up tables, and the like, which may carry out a variety of functions under the control of one or more microprocessors or other control devices. Similarly, the software elements of the system may be implemented with any programming or scripting language such as C, C++, C#, Java, JavaScript, VBScript, Macromedia Cold Fusion, COBOL, Microsoft Active Server Pages, assembly, PERL, PHP, AWK, Python, Visual Basic, SQL Stored Procedures, PL/SQL, any UNIX shell script, and extensible markup language (XML) with the various algorithms being implemented with any combination of data structures, objects, processes, routines or other programming elements. Further, it should be noted that the system may employ any number of conventional techniques for data transmission, signaling, data processing, network control, and the like. Still further, the system could be used to detect or prevent security issues with a client-side scripting language, such as JavaScript, VBScript or the like.
[0092] The systems and methods of the present disclosure may be embodied as a customization of an existing system, an add-on product, a processing apparatus executing upgraded software, a stand alone system, a distributed system, a method, a data processing system, a device for data processing, and/or a computer program product. Accordingly, any portion of the system or a module may take the form of a processing apparatus executing code, an internet based embodiment, an entirely hardware embodiment, or an embodiment combining aspects of the internet, software and hardware. Furthermore, the system may take the form of a computer program product on a computer-readable storage medium having computer-readable program code means embodied in the storage medium. Any suitable computer-readable storage medium may be utilized, including hard disks, CD-ROM, optical storage devices, magnetic storage devices, and/or the like.
[0093] The system and method is described herein with reference to screen shots, block diagrams and flowchart illustrations of methods, apparatus (e.g., systems), and computer program products according to various embodiments. It will be understood that each functional block of the block diagrams and the flowchart illustrations, and combinations of functional blocks in the block diagrams and flowchart illustrations, respectively, can be implemented by computer program instructions.
[0094] These computer program instructions may be loaded onto a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions that execute on the computer or other programmable data processing apparatus create means for implementing the functions specified in the flowchart block or blocks. These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart block or blocks. The computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks.
[0095] Accordingly, functional blocks of the block diagrams and flowchart illustrations support combinations of means for performing the specified functions, combinations of steps for performing the specified functions, and program instruction means for performing the specified functions. It will also be understood that each functional block of the block diagrams and flowchart illustrations, and combinations of functional blocks in the block diagrams and flowchart illustrations, can be implemented by either special purpose hardware-based computer systems which perform the specified functions or steps, or suitable combinations of special purpose hardware and computer instructions. Further, illustrations of the process flows and the descriptions thereof may make reference to user windows, webpages, websites, web forms, prompts, etc. Practitioners will appreciate that the illustrated steps described herein may comprise in any number of configurations including the use of windows, webpages, web forms, popup windows, prompts and the like. It should be further appreciated that the multiple steps as illustrated and described may be combined into single webpages and/or windows but have been expanded for the sake of simplicity. In other cases, steps illustrated and described as single process steps may be separated into multiple webpages and/or windows but have been combined for simplicity.
[0096] The term “non-transitory” is to be understood to remove only propagating transitory signals per se from the claim scope and does not relinquish rights to all standard computer-readable media that are not only propagating transitory signals per se. Stated another way, the meaning of the term “non-transitory computer-readable medium” should be construed to exclude only those types of transitory computer-readable media which were found in In Re Nuijten to fall outside the scope of patentable subject matter under 35 U.S.C. §101.
[0097] Benefits, other advantages, and solutions to problems have been described herein with regard to specific embodiments. However, the benefits, advantages, solutions to problems, and any elements that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as critical, required, or essential features or elements of the disclosure.
[0098] Although the disclosure includes a method, it is contemplated that it may be embodied as computer program instructions on a tangible computer-readable carrier, such as a magnetic or optical memory or a magnetic or optical disk. All structural, chemical, and functional equivalents to the elements of the above-described exemplary embodiments that are known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the present claims. Moreover, it is not necessary for a device or method to address each and every problem sought to be solved by the present disclosure, for it to be encompassed by the present claims. Furthermore, no element, component, or method step in the present disclosure is intended to be dedicated to the public regardless of whether the element, component, or method step is explicitly recited in the claims. No claim element herein is to be construed under the provisions of 35 U.S.C. 112, sixth paragraph, unless the element is expressly recited using the phrase “means for.” As used herein, the terms “comprises”, “comprising”, or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
[0099] Where a phrase similar to “at least one of A, B, or C,” “at least one of A, B, and C,” “one or more A, B, or C,” or “one or more of A, B, and C” is used, it is intended that the phrase be interpreted to mean that A alone may be present in an embodiment, B alone may be present in an embodiment, C alone may be present in an embodiment, or that any combination of the elements A, B and C may be present in a single embodiment; for example, A and B, A and C, B and C, or A and B and C.
[0100] Changes and modifications may be made to the disclosed embodiments without departing from the scope of the present disclosure. These and other changes or modifications are intended to be included within the scope of the present disclosure, as expressed in the following claims. | Among other things, embodiments of the present disclosure help provide entities with the ability to remotely detect behavior associated with malware and identify compromised user-sessions, regardless of the malware variant or family, and independently of the page structure. | 6 |
BACKGROUND OF THE INVENTION
[0001] The subject of this invention is an aerodynamic and spatial mixed flight aircraft, and the related piloting method thereof.
[0002] The field of the invention is that of spaceplanes, i.e. vehicles capable of taking off from the ground like aircraft, reaching space and returning by landing on Earth, also like aircraft. These vehicles must be able to carry a payload and offer suitable safety conditions for manned flights, like conventional aircraft, and they must in particular be reusable, unlike rockets, which are consumed during the launch at the end of the flight. The term space may be understood according to International Aeronautical Federation terminology, which refers to the entire designated volume outside the Earth's atmosphere, above one hundred kilometres in altitude by convention. It may also be considered as the volume where the atmosphere is too rarefied to enable the flight of conventional aircraft.
[0003] A distinction may be made between orbital aircraft, which are capable of reaching the orbital speed at a given altitude (of the order of 7.5 km/s at 200 km in altitude), and suborbital aircraft, which are unable to do so. Orbital aircraft are capable of becoming satellites remaining for an almost indefinite time in orbit after the propulsion phase, whereas suborbital aircraft follow a trajectory which returns them to Earth when the propulsion phase thereof is complete, after a finite time, of the order of an hour and a half, or less. Orbital aircraft are distinguished from suborbital aircraft particularly by the quantity of energy to be carried to reach the orbital speed and by the specific design received to withstand the considerably greater overheating experienced on re-entering the atmosphere. The present invention firstly relates to suborbital aircraft, but not exclusively since it would be conceivable to apply it to orbital aircraft with quantitative or secondary modifications, and it may also transport a vehicle capable of orbital flight as its payload.
[0004] Unlike rockets which have already been the subject of significant industrial developments, spaceplanes are still very infrequent, and many only exist in the project phase. A first example is the American shuttle which is not, however, a spaceplane per se but a two-stage composite launcher, taking off like a rocket and wherein only the second stage, which is released after the takeoff phase, is a space glider. This space glider has the dual advantage, sought with the invention, of being able to be reused and land on Earth in the same way as a supersonic glider, therefore at a high speed and without being able to correct an error; however, the first stage retains the drawbacks of the rocket, primarily the single use and the high consumption of propellant or fuel to pull away from the near atmosphere.
[0005] A second example of a spaceplane was devised by Scaled Composite; it also has two stages. A first aerodynamic flight aircraft pulls another to around 15 km in altitude and releases it. The second aircraft has an anaerobic rocket engine, capable of carrying the payload to 100 km in altitude. Said second stage lands similarly to that of the shuttle.
[0006] A third, substantially older, example, is the American X15 prototype, which was released from a carrier aircraft and could reach an altitude greater than 100 km.
[0007] Other space vehicles are described in the website http://www.spacefuture.com/vehicles/designs.shtml, but these vehicles have not been built or commissioned. Some take off vertically, but their propulsion mode remains as costly as that of a rocket, or they are associated with a rocket serving as a first stage thereof, such as the American space shuttle.
[0008] The documents EP 0 264 030, GB 2 362 145, WO 98/30 449, WO01/64513, U.S. Pat. No. 6,119,985, U.S. Pat. No. 6,745,979, US 2005/0279889, U.S. Pat. No. 6,193,187 and FR 1 409 570 respectively illustrate a two-stage launcher; a launcher wherein a balloon is the first stage; an aircraft pulling another; a launcher wherein the first stage is a composite propulsion launcher for aeronautical engines and rocket engines; a spacecraft fuelled with oxygen; three variable geometry aircraft; and a conventional aircraft (with a propeller in the embodiment shown) whereto orientation modification nozzles have been adjoined, which are auxiliary engines not involved in propulsion.
[0009] Therefore, the majority of aircraft projects in space, and the only ones to have flown have multiple stages. This design appears to be more advantageous in that it allows a more beneficial ratio between the effective mass and the mass at takeoff, which offers the possibility of associating a greater quantity of fuel with the payload and therefore propel same further. The drawbacks are that the complexity is increased considerably and that the upper stage has reduced scope for movement. The two stages must all be equipped with the same means for some functions, such as the directional nozzles to adjust the orientation thereof and they must also comprise separation means. The upper stage is not piloted effectively for the return and must re-enter in glide mode. This and the circumstance that the release means may be subject to failures renders the flight more risky.
[0010] Some aircraft used composite aerobic and anaerobic propulsion, to circulate successively in the dense atmosphere and in space. This idea is used in the invention, more effectively however as prior designs do not generally make it possible to do away with the constraint of multiple stages. The main reason lies in a different choice of wings, as it appeared to the present inventors that the wings generally proposed for said prior designs were short, delta-shaped wings with a large back-sweep, well-suited to supersonic flights but wherein the lift is less satisfactory. On the other hand, the design according to the invention uses a long, straight wing, with a small back-sweep, to provide a satisfactory lift in the dense atmosphere and up to a high altitude. These portions of the voyage are completed without problems at subsonic speed. The rocket propulsion only starts at a relatively high atmosphere so that the aerodynamic forces remain manageable for the wing. In this case, it is not necessary to adopt a variable geometry to protect the wing and reduce the drag by folding it back against the fuselage.
[0011] On the contrary, a rigid, simpler, lighter design is preferred, requiring less maintenance and not subject to damage.
SUMMARY OF THE INVENTION
[0012] As a general rule, it was sought to optimise the atmospheric flight in terms of consumption, altitude and mass; this led to the adoption of the high-altitude subsonic flight concept, and made it possible to optimise the total mass, and the rocket propulsion in particular, as less mass for the atmospheric flight implies less rocket propulsion and less fuel for the atmospheric flight, and again less mass and less fuel for the atmospheric flight: it was possible to achieve a relatively simple, light and energy-efficient aircraft to carry its own fuel, without a separate auxiliary launcher or in-flight refuelling, and capable of starting and ending the flight like a conventional aircraft, with piloting and horizontal orientation. It is necessary to underline the advantage of being able to pilot and direct the aircraft during the return flight, compared to gliding returns, to improve the safety of manned flights. In this way, the aircraft will be able to cover significant distances after the return thereof into the atmosphere and choose the landing strip. The end of flight speed will be much slower than with a delta wing vehicle devised for supersonic flight.
[0013] An aim of the invention is to do away with the drawbacks of the prior designs and supply a new kind of spacecraft, with a single stage capable of flying correctly, with full piloting capacities, at low altitude while being able to continue the voyage thereof in space. This aircraft will have the general outer appearance of a commercial aircraft and will differ from a conventional aircraft by certain arrangements.
[0014] In a general embodiment, the aircraft according to the invention comprises a fuselage, an essentially straight and elongated fixed transverse wing, having a greater span than the length of the fuselage, aeronautical engines positioned on the fuselage or in the fuselage, and propellant or fuel propulsion units. This composition guarantees satisfactory piloting possibilities at both low altitude and high altitude.
[0015] Preferentially, the wing span and the length of the fuselage are in a ratio between 1 and 2; more preferentially, between 1 and 1.4. The surface loading (ratio between the wing surface and the total mass of the aircraft, which determines the altitude reached in subsonic flight) is preferentially between 2.5 and 3.3 m 2 per tonne. The unladen mass is preferentially between 40% and 60% of the laden mass.
[0016] According to an important possibility, the propellant or fuel tanks are positioned in a rear portion of the fuselage, the wing is positioned on said rear portion, a front portion of the fuselage comprises a cabin for the pilot and the passengers and the aircraft comprises a forward tail group placed on said front portion. The aircraft is in this case devised for the transport of passengers, the high loads at takeoff being at the rear and the wing also being moved to the rear with respect to conventional aircraft designs in order to account for the very rearward position of the centre of gravity. The forward tail group at the front restores the stability and thus assists with the lift.
[0017] The invention also relates to an aircraft piloting method comprising a first aerodynamic flight step using aeronautical engines, a second space launch flight step using rocket propulsion units after controlling an aircraft inclination change between the first step and the second step, a third gliding descent step with the fuselage substantially perpendicular to the trajectory, and a fourth aerodynamic flight landing step after repositioning the aircraft substantially in the direction of the trajectory between the third flight step and the fourth flight step.
[0018] The rocket propulsion is preferentially with variable thrust.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] These aspects of the invention along with others will now be described with reference to the figures, wherein:
[0020] FIGS. 1 and 2 are an oblique view and a front view of the aircraft,
[0021] and FIG. 3 illustrates a step of the flight.
DETAILED DESCRIPTION
[0022] The aircraft comprises a fuselage 1 having a general cylindrical shape but tapering to the front to a nose 2 . From the fuselage 1 protrude a transverse wing 3 with a significant elongation in the lateral direction of the aircraft and a small back-sweep and which is located at the rear of the fuselage 1 , at approximately 80% of the total length to the front, a transverse forward tail group 4 at the front, not far from the nose 2 , and an upper fin 5 to the rear, with a large back-sweep, comparable to that of a conventional aircraft. The wing 3 is in this case positioned at a lower portion of fuselage 1 , but it could be at mid-height or at a high height. It is also important to mention a landing gear 6 under the fuselage 1 and a pair of aeronautical engines 7 (turbojets), also located in the rear part of the fuselage 1 but somewhat to the front of the wing 3 . The aeronautical engines 7 are, in this embodiment, mounted on the lateral sides of the fuselage 1 somewhat above same via fixing masts and platforms extending out from the fuselage 1 . This design is not obligatory and the aeronautical engines 7 could be integrated in the structure of the fuselage 1 , air intakes of same offering access to the combustion air and an outlet to the combustion gases.
[0023] The main interior arrangements of the aircraft are as follows. The volume of the fuselage 1 is divided into three main compartments by a front partition and a rear partition 9 . A front compartment 10 housed by the nose 2 and at the front of the front partition 8 contains the control systems. A median compartment 11 is in this case the cabin containing the pilot and the passengers. The cabin is airtight, pressurised, equipped with doors and windows for access and observation, and equipped with equipment and fittings for transporting people. A rear compartment 13 at the rear of the rear partition 9 is assigned to propulsion. It comprises large propellant or fuel tanks 14 and 15 able to fuel two rocket propulsion units 16 and 17 positioned at the very rear of the aircraft and protruding outward. The use of a plurality of rocket propulsion units 16 and 17 (two or three in general) makes it possible to fire them in succession and offer a more progressive propulsion. A single propulsion unit may be used. In this case, it advantageously consists of variable thrust. The fuel required for the aeronautical engines 7 is contained in the wing 3 . Finally, there is a smaller tank (not shown) than the propellant or fuel tanks 14 and 15 and wherein the function is to supply the aircraft orientation modification nozzles. Some of these nozzles bear the reference 19 and are positioned at the ends of the wing 3 , oriented upwards and downwards to control aircraft rolling movements. Other nozzles 20 and 21 are positioned on the nose 2 of the aircraft and directed in vertical and horizontal direction in order to control pitching and yaw movements.
[0024] The aeronautical engines 7 and the rocket propulsion units 16 and 17 , all arranged to exert a thrust to the front of the aircraft and therefore propel same, are the main engines thereof. The nozzles 20 and 21 are small auxiliary engines with no effect on the propulsion per se, as they only exert a rotation action by means of a displacement in the lateral direction.
[0025] The embodiment illustrated essentially herein was designed to transport four passengers and one pilot to an altitude of approximately 100 km, therefore a payload of 500 kg. The length of the aircraft is 10 to 15 m and the span thereof 15 to 25 m, the fuselage 1 having a height of approximately 2 m and capable of having circular or elliptical cross-sections. The wing 3 has a surface area of 35 m 2 , the tail group 4 a span of 6 m and a surface area of 5 m 2 , and the fin 5 a surface area of 10 m 2 and a height of approximately 4.5 m. The propellant or fuels may be liquid oxygen and liquid methane. The aircraft having a low mass and the mass of the propellant or fuels being low, it becomes simpler and more reliable. The mass at takeoff may be 10 to 15 tonnes including 5 to 7 tonnes of unladen mass, 3 to 5 tonnes of propellant or fuels, 0.5 to 2 tonnes of mass of kerosene, the remainder including the payload. The thrust of the aeronautical engines may be from 3000 to 7000 lbf (13.3 kN to 31.1 kN), the thrust of the rocket propulsion units from 150 to 400 kN, and the nozzles 19 , 20 and 21 may each have approximately 400 N of thrust. In order to reduce the unladen mass, the structure of the aircraft will be advantageously made of composite materials as for the tanks, or made of aluminium-based light alloy such as aluminium-lithium.
[0026] How the aircraft completes the flights for which it was devised will now be described.
[0027] A first step relates to the takeoff and climbing flight to an altitude of up to 12, or 14 to 18 km approximately, preferentially above the general air traffic altitudes. Only the aeronautical engines 7 are used for this. No in-flight fuelling is performed, either with fuel for the aeronautical engines 7 , or with propellant or fuel for the fixed engines 16 and 17 : the aircraft carries all its fuel. The wing 3 is designed to favour the climbing flight to this altitude by offering the lift required to reach same, and being associated with a flight at subsonic speed, from Mach 0.5 to Mach 0.8, or possibly preferentially from Mach 0.5 to Mach 0.6, to thrust gently on the aircraft while making it climb as high as possible subject to high fuel consumption; the wing 3 is in any case poorly suited to supersonic speeds. After this first flight step, the rocket propulsion units 16 and 17 are fired, the aeronautical engines 7 switched off, and the lift of the wing 3 is used to rectify the trajectory to approximately 70° with respect to the horizontal. The forces on the aircraft structure are reduced as the firing of the rocket propulsion units 16 and 17 only starts at this high altitude due to the rarefied atmosphere, which makes it possible to retain a light structure and, in correlation, require a lower fuel mass. The mass of propellant or fuel required is in turn reduced due to the firing of the rocket propulsion units 16 and 17 at high altitude, owing to the subsonic flight. The rocket propulsion units 16 and 17 are started up successively in order to limit the forces in the first thrust phase. It is envisaged to mask the air inlet of the aeronautical engines 7 to prevent them from being subject to overheating and excessive gas velocities. The flight speed becomes supersonic, up to approximately Mach 3 or Mach 4. When the propellant or fuel has been used up, the rocket propulsion units 16 and 17 are switched off but the aircraft continues to climb by inertia up to an altitude of up to 80 to 120 km.
[0028] The third phase relates to the re-entry into the atmosphere, with all the propulsion unit engines being switched off. The angle of incidence of the aircraft is approximately 90°, i.e. it is oriented with its extension perpendicular to the trajectory in order to oppose the greatest drag resistance to maximise braking. Then, at an altitude of approximately 40 km, the angle of incidence is reduced to approximately 40°. This measure should make it possible to reduce the aerodynamic forces. The acceleration subjected to the passengers sought should not exceed approximately 5 g.
[0029] At the altitude of approximately 25 km, the speed of the aircraft returns to a subsonic level, the aircraft retrieves an aeronautical flight angle of incidence, the aeronautical engines 7 are fired or not, and the aircraft returns to Earth either by gliding or by means of motorised flight to a landing strip.
[0030] Some applications of the invention may be space tourism, the completion of microgravity experiments, the use of the aircraft as a first reusable stage of a satellite, or rapid passenger transfer. | An aircraft having propulsion units for both conventional aircraft flight in the atmosphere and for high-altitude operation as a rocket. The aircraft is divided into a payload compartment and a compartment containing rocket propulsion unit propellant or fuel, and includes a long transverse wing with a small back-sweep to favour lift in the dense layers of the atmosphere and to thus make it possible to climb to high altitudes at a subsonic speed before using the rocket propulsion units. The return flight portion is performed by gliding or controlled as for a conventional aircraft. | 1 |
BACKGROUND
[0001] The present disclosure relates to a system for controlling the rolling of a vehicle and a method therefor which are able to control the steering of a vehicle in such a way to adjust the inclination of the vehicle, and in particular to a system for controlling the rolling of a vehicle and a method therefor wherein the steering of the vehicle can be controlled in such a way that a sill connection plate is provided to connect left and right side sills of the vehicle, by which a wheel and a frame can be inclined in a desired direction during the change of the direction of the vehicle, thus controlling the steering of the vehicle, and a driving motor is provided at each wheel of the vehicle to control the speed of each driving motor, thus controlling the steering of the vehicle.
[0002] The necessity on the development of an environmentally friendly future type vehicle or a predetermined transportation means is currently on the rise together with the increasing demand for an enhanced driver's driving convenience and safety. In order to satisfy these needs, a finished vehicle maker and a vehicle component maker are developing related technologies.
[0003] In the sector of a vehicle chassis system (a driving, a steering, a suspension, a braking system, etc.), various researches and developments are underway as the performance of each electronic part and a chassis control technology advance more and more. In order to enhance the driving performance of a vehicle, each device and control system are being developed to cooperate each other, not simply combined.
[0004] The rolling system is a system which would be applied to an environmental friendly future type vehicle or a predetermined transportation means and in general is formed of a driving motor which is provided at each wheel of the vehicle, a wheel and a frame which are configured to incline based on the change of the driving direction, and a combination of a steering part and a driving part.
[0005] The driving direction change of the conventional vehicle can be carried out by rotating leftward or rightward a steering link provided to connect a front axle and a wheel of the vehicle in the direction which is horizontal to the ground. The above described conventional steering method has a problem wherein a centripetal force occurring during the turning of the vehicle may has bad effect on the riding comfort of a driver and passenger, and since the surface of each tire continuously contacts with the ground, and the tires may wear out a lot due to the frictions, thus degrading the durability of the vehicle. According to the conventional technology, since the direction change of the vehicle should be carried out only by rotating the steering link which is connected to the axle, it is impossible to carry out direction changes in response to different variables when the vehicle is driven on the corners.
[0006] The Korean Patent Registration Number 0241375 (hereinafter referred to “a prior art”) describes the device for compensating the left and right leanings of the vehicle. More specifically, the above-mentioned prior art describes the device for compensating the left and right leanings of the vehicle in such a way that a vehicle speed, a steering angle, a lateral direction inclination of a road and a weight on each wheel are detected during the driving direction changes of the vehicle, and the lateral inclinations of the vehicle can be previously controlled, thus previously minimizing the lateral force that the driver and passenger may feel.
[0007] The above described prior art, however, describes that the inclinations of the vehicle can be maintained by simply outputting a compensation signal to an actuator, namely, it does not specifically describe any method to control the inclinations of the vehicle and does not suggest any resolution to other matters related to the durability degradation due to the friction of the tires and the controls during the direction changes of the vehicle.
[0008] For this reason, it needs to urgently develop a new vehicle rolling system which is able to resolve the above listed problems.
[0009] The present invention has been invented based on the above-mentioned technology background. The present invention is able to satisfy the above mentioned technical needs and provide additional technical components that a person having ordinary skill in the art cannot easily invent.
[0010] The present invention has been invented during the procedure to satisfy any technical needs to the vehicle chassis system, and an applicable range thereof is not limited to the vehicle chassis system. In other words, the present invention may be adapted or applied various transportation fields within a range covering the technical concepts which will be described below.
[0011] The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.
SUMMARY OF THE DISCLOSURE
[0012] The present invention has been made in an effort to solve the above-described problems associated with prior art.
[0013] An object of the present invention is to provide a system for controlling the steering of a vehicle in such a way that a frame is provided, which includes a sill connection plate and a sill connection shaft which connect left and right side sills of a vehicle, and the wheels connected to the front and rear axles of the vehicle and the frame are inclined leftward or rightward of the direction vertical to the ground during the rotation of the sill connection shaft, thus controlling the steering of the vehicle.
[0014] Another object of the present invention is to provide a system which is able to simultaneously control a vehicle to turn in the horizontal direction with respect to the ground and the inclination of a vehicle body in the vertical direction with respect to the ground when changing the driving direction of the vehicle in such a way to provide a steering link which can be rotated leftward or rightward in the horizontal direction with respect to the ground.
[0015] Further another object of the present invention is to provide a system for controlling the steering of a vehicle by controlling the speed of a driving motor in such a way to provide a driving motor and an electronic transmission to each wheel of the vehicle.
[0016] Still further another object of the present invention is to provide a system which is able to maintain a stable driving of a vehicle with the aid of a steering control and a driving control in such a way to detect a vehicle state information using a sensor unit and calculate a compensation value with respect to the detected vehicle state information.
[0017] Meanwhile, the technical resolutions of the present invention are not limited to the above-mentioned technical resolutions, and various technical resolutions may be further provided within a range wherein a person having ordinary skill in the art can draw from the descriptions of the present invention.
[0018] The present invention provides as a means for resolving the above problems a system and method for controlling the rolling of a vehicle, and it is noted that the categories of these inventions are not limited to the expressions used herein the specification, but can be interpreted into various meanings within the scope of the present invention.
[0019] Accordingly, in one aspect, the present invention provides a system for controlling the rolling of a vehicle which is formed of a sill connection shaft provided to connect left and right side sills 130 and a sill connection plate 110 of a vehicle and is able to adjust the inclination of the vehicle with the aid of a steering force transferred from a steering unit, a front axle 140 and a rear axle 150 provided to connect a front wheel 170 and a rear wheel 170 and transfer a steering driving force to each wheel 170 , and a frame 50 which allows to control the inclination of the vehicle with the aid of the rotation of the sill connection shaft 117 , which may include, but is not limited to, a control unit 500 which is able to analyze a steering signal received from a steering operation mechanism 200 and a driving signal received from a driving operation mechanism 400 and generate and transmit a steering control signal and a driving control signal which are used to control the steering unit 100 and the driving unit 300 based on a result value of the analysis; a steering unit 100 which is able to rotate the sill connection shaft 117 in such a way to drive an inclination control motor 185 in response to a steering control signal from the control unit 500 and transfer a steering force to the sill connection shaft 117 and is able to control the driving direction of the vehicle in such a way to incline the frame 50 and the wheel 170 leftward or rightward of the driving direction of the vehicle based on the direction vertical to the ground in accordance with a rotation of the sill connection shaft 117 ; and a driving unit 300 which is able to drive the vehicle in accordance with a driving control signal received from the control unit 500 .
[0020] In the system for controlling the rolling of the vehicle, the vehicle includes a steering link 160 which is provided to connect each wheel 170 and the axle of the vehicle and can be rotatable leftward or rightward of the driving direction of the vehicle with respect to the direction horizontal to the ground, and the steering unit 100 is able to control the driving direction of the vehicle in such a way to incline the frame and the wheel 170 leftward or rightward of the driving direction of the vehicle with respect to the direction vertical to the ground in accordance with a rotation of the sill connection shaft 117 when controlling the driving direction of the vehicle and is able to control the driving direction of the vehicle in such a way to rotate the steering link 160 leftward or rightward with respect to the direction horizontal to the ground.
[0021] Moreover, in the system for controlling the rolling of the vehicle, the vehicle includes a driving motor 310 to transfer a driving force to each wheel 170 , and an electronic transmission to control the driving motor 310 , and the control unit 500 is able to generate a driving control signal to control the speed of the driving motor 310 of each wheel 170 and transfers it to the driving unit 300 , and the driving unit 300 is able to drive the vehicle in such a way to adjust the speed of the driving motor 310 of each wheel in accordance with the received driving control signal.
[0022] Furthermore, the driving unit 300 is able to change the driving direction of the vehicle in the leftward direction in such a way that the speed of the driving motor 310 of the left wheel 170 of the vehicle is decreased, and the speed of the driving motor 310 of the right wheel 170 of the vehicle is increased or maintained and is able to change the driving direction of the vehicle in the rightward direction in such a way that the speed of the driving motor 310 of the right wheel 170 of the vehicle is decreased, and the speed of the driving motor 310 of the left wheel 170 of the vehicle is increased or maintained.
[0023] In the system for controlling the rolling of the vehicle, the steering unit 100 is able to change the driving direction of the vehicle in the rightward direction in such a way that the frame 50 including the wheel 170 is controlled to incline rightward by rotating the sill connection shaft 117 in the rightward direction of the vehicle body and is able to change the driving direction of the vehicle in the leftward direction in such a way that the frame 50 including the wheel 170 is inclined leftward by rotating the sill connection shaft 117 in the leftward direction of the vehicle body.
[0024] Moreover, the system for controlling the rolling of the vehicle may further include a sensor unit which is able to detect a vehicle state information formed of at least one among an inclination, a rotational inertial force, the size of a centrifugal force and an acceleration of the vehicle and transmit the detected information to the control unit 500 .
[0025] In the system for controlling the rolling of the vehicle, the control unit 500 generates a steering control signal in such a way that if a vehicle state information including the size of a centrifugal force is received from the sensor unit, a difference between the size of the centrifugal force and the previously set reference value is obtained, and a compensation value is calculated for the difference to become zero (0), thus generating a steering control signal, and the steering unit 100 is able to control the inclination of the vehicle by rotating the sill connection shaft 117 in accordance with the steering control signal.
[0026] The system for controlling the rolling of the vehicle may further include a tire which is installed at each wheel 170 , and the thread of the tire is formed in a semicircular shape which has a predetermined curvature.
[0027] In addition, the steering signal and the driving signal are PWM (Pulse Width Modulation) signals.
[0028] In the system for controlling the rolling of the vehicle, the steering unit 100 is able to independently control the steering links which are connected to the front axle and the rear axle.
[0029] In another aspect, the present invention provides a method for controlling the rolling of a vehicle, which may include, but is not limited to, (a) a step wherein a steering operation mechanism 200 and a driving operation mechanism 400 receive a steering signal and a driving signal and transfer them to a control unit 500 ; data used to change the driving direction of the vehicle and a data used to drive the vehicle and generates a steering control signal and a driving control signal based on the calculated data and transfers them to the steering unit 100 and the driving unit 300 ; and (d) a step wherein the steering unit 100 controls the driving direction of the vehicle in such a way that the frame including the wheel 170 of the vehicle is inclined leftward or rightward of the driving direction of the vehicle based on the direction vertical to the ground by controlling a sill connection shaft 110 or a steering link 160 in accordance with the received steering control signal or the frame including the wheel 170 of the vehicle is inclined leftward or rightward of the driving direction of the vehicle based on the direction horizontal to the ground, and the driving unit 300 adjusts the speed of a driving motor 310 connected to each wheel 170 in accordance with the received driving control signal.
[0030] In further another aspect, the present invention provides a method for controlling the rolling of a vehicle, which may include, but is not limited to, (a) a step wherein a steering operation mechanism 200 and a driving operation mechanism 400 receive a steering signal and a driving signal and transfer them to a control unit 500 ; (b) a step wherein the control unit 500 analyzes the received steering signal and driving signal; (c) a step wherein the control unit 500 calculates a data used to change the driving direction of the vehicle and a data used to drive the vehicle and generates a steering control signal and a driving control signal based on the calculated data and transfers them to the steering unit 100 and the driving unit 300 ; (d) a step wherein the steering unit 100 controls the driving direction of the vehicle in such a way to rotate the steering link 160 leftward or rightward of the driving direction of the vehicle based on the direction horizontal to the ground; (e) a step wherein a sensor unit detects the vehicle state information of the vehicle and transmits it to the control unit 500 ; and (f) a step wherein the control unit 500 generates a steering control signal by calculating a compensation value with respect to the vehicle state information received from the sensor unit, and the steering unit 100 controls the inclination of the vehicle by rotating a sill connection shaft 117 in accordance with the steering control signal.
[0031] In the method for controlling the rolling of the vehicle, the vehicle state information may include at least one of a rotational inertial force, an inclination of the vehicle, an acceleration, the size of a centrifugal force of the vehicle, etc.
[0032] The system or method for controlling the rolling of the vehicle according to the present invention may further include various technical components within the scope of the present invention by a person having ordinary skill in the art.
[0033] The present invention provides a system for changing the direction of a vehicle in such a way to control the inclinations of a frame and wheels, by means of which the driving safety can be enhanced since the distance between the center of a vehicle body and the ground decreased during the change of the direction of the vehicle.
[0034] In the present invention, it is possible to enhance the durability of tires in such a way that the contacting portions between the tires and the ground change in response to the inclination of the vehicle during the change of the direction of the vehicle.
[0035] Since the driving direction of the vehicle can be controlled based on the control of the inclination and the steering link of the vehicle, the vehicle steering control can be more effectively carried out as compared to the conventional technology.
[0036] In the present invention, the direction of the vehicle can be changed by controlling the driving speed of each wheel, whereupon the steering can be more effectively controlled as compared to the vehicle direction change which is carried using only the steering unit.
[0037] In the present invention, a sensor unit can be further provided, which is able to detect a vehicle state information during the change of the direction of the vehicle, and the driving stability of the vehicle can be enhanced in such a way to control the inclination of the vehicle with the aid of the calculated compensated value which may be used to stabilize the vehicle based on the vehicle state information.
[0038] The advantageous effects of the present invention are not limited to the above-described effects, and various effects may be further provided within a range where a person having ordinary skill in the art can draw from the descriptions below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0039] The above and other features of the present invention will now be described in detail with reference to certain exemplary embodiments thereof illustrated the accompanying drawings which are given hereinbelow by way of illustration only, and thus are not limitative of the present invention, and wherein:
[0040] FIG. 1 is a view illustrating a schematic configuration of a system for controlling the rolling of a vehicle according to an embodiment of the present invention;
[0041] FIG. 2 is a plane view schematically illustrating a frame, a steering unit and a driving unit of a vehicle;
[0042] FIG. 3 is a view illustrating an exemplary operation wherein a control unit receives a steering signal and a driving signal and transmits to the steering unit and the driving unit;
[0043] FIG. 4 is a view illustrating an exemplary structure wherein a sill connection shaft can rotate with the aid of a steering operation unit and a control unit according to an embodiment of the present invention;
[0044] FIG. 5 is a view illustrating an exemplary operation wherein an axle, wheels and tires are inclined during the change of the direction of the vehicle according to an exemplary embodiment of the present invention;
[0045] FIG. 6 is a view illustrating an exemplary operation wherein a vehicle is inclined in the left or right direction of the vehicle driving direction based on the vertical or horizontal direction with respect to the ground or rotates according to an embodiment of the present invention;
[0046] FIG. 7 is a view illustrating a state where the portions contacting with the tires when the vehicle is being driven are classified according to the present invention;
[0047] FIG. 8 is a time series flow chart for describing a method for controlling the rolling of a vehicle according to an embodiment of the present invention; and
[0048] FIG. 9 is a time series flow chart for describing a method for controlling the rolling of a vehicle according to another embodiment of the present invention.
LEGEND OF REFERENCE NUMBERS
[0000]
50 : Frame
100 : Steering unit
110 : Sill connection plate
115 : Metallic member
117 : Sill connection shaft
120 : Center sill
130 : Side sill
140 : Front axle
150 : Rea axle
160 : Steering link
170 : Wheel
175 : Joint unit
180 : Steering link control motor
185 : Inclination control motor
200 : Steering operation mechanism
300 : Driving unit
310 : Driving motor
400 : Driving operation mechanism
500 : Control unit
[0068] It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various preferred features illustrative of the basic principles of the invention. The specific design features of the present invention as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes will be determined in part by the particular intended application and use environment.
[0069] In the figures, reference numbers refer to the same or equivalent parts of the present invention throughout the several figures of the drawing.
DETAILED DESCRIPTION OF THE INVENTION
[0070] The system for controlling the rolling of a vehicle and a method therefor according to the present invention will be described with reference to the accompanying drawings. The embodiments below are provided to help a person having ordinary skill in the art to easily understand the technical concepts of the present invention, and the ranges of the embodiments of the present invention are not limited thereto. The components shown in the drawings are illustrated for the sake of easier descriptions of the embodiments of the present invention and may be seen different as compared to the actual components.
[0071] Each component below is provided for only illustrative purpose to implement the present invention. In another embodiment of the present invention, another component may be employed without departing from a concept and range of the present invention. Each component may be formed of only a hardware or a software, but various hardware and software may be combined to carry out the same functions.
[0072] The term “comprise” means an open expression to simply indicate a predetermined component, and it should not be interpreted as excluding another component.
[0073] The term “connected” or “linked” means that a predetermined component may be directly connected to another component or it may be connected thereto via another component.
[0074] The system for controlling the rolling of a vehicle according to an embodiment of the present invention will be described with reference to FIG. 1 .
[0075] Referring to FIG. 1 , the system for controlling the rolling of the vehicle according to an embodiment of the present invention may include, but is not limited to, a steering unit 100 which is provided to control a driving direction of the vehicle, a driving unit 300 which is provided to control the driving of the vehicle, and a control unit 500 which is provided to control the driving unit 300 . The vehicle may equip with a frame which is able to form the type of the vehicle which includes a function.
[0076] The steering unit 100 is able to carry out a function to control the driving direction of the vehicle. More specifically, it is able to supply a steering force to the sill connection plate 110 in accordance with a steering control signal received from the control unit 500 , thus rotating the sill connection shaft 117 , and carry out a function to control the driving direction of the vehicle in such a way to incline the frame 50 including the wheel 170 leftward or rightward of the driving direction of the vehicle based on the vertical direction with respect to the ground.
[0077] Here, the operation where the wheel is included in the leftward or rightward direction of the driving direction of the vehicle based on the vertical direction with respect to the ground can be easily understood with reference to FIG. 6 . More specifically, assuming that there may be a virtual surface which is formed vertical with respect to the ground when it is passing through the center of the vehicle, it means that a corresponding vertical surface is inclined in the leftward or right direction of the driving direction of the vehicle. At this time, the wheel 170 of the vehicle may position parallel with the virtual vertical surface, so the driving direction of the vehicle can be controlled in response to the inclination of the wheel.
[0078] The operation where the frame 50 including the wheel 170 is inclined to one side of the driving direction of the vehicle in response to the rotation of the sill connection shaft 117 can be carried out by increasing the angle that the side sills 130 of both sides form with respect to the ground. In case of the rotation of the sill connection shaft 117 , the vehicle can be inclined toward one side since the wheel connected to both the front axle 140 and the rear axle 150 of the vehicle can be inclined at the same angle as the angle that the side sill 130 forms with respect to the ground. More specifically, the steering unit 100 will steer the driving direction of the vehicle toward the rightward direction in such a way that the frame 50 including the wheel 170 is inclined toward the right side of the driving direction of the vehicle with respect to the direction vertical to the ground by rotating the side sill 130 in the rightward direction of the vehicle body, and on the contrary the driving direction of the vehicle can be turned toward the leftward direction since the wheel 170 and the frame 50 are inclined toward the leftward direction by rotating the sill connection shaft 117 toward the leftward direction of the vehicle body.
[0079] Meanwhile, the front axle 140 and the rear axle 150 may be directly connected to the wheel 170 or they may be connected thereto via a link which may be disposed between each axle and the wheel 170 and is able to rotate in the direction perpendicular to the ground. In case where they are connected by using the link between each axle and the wheel 170 , the wheel 170 can be inclined at an angle which is different from the angle that the vehicle is inclined, in response to the rotation of the sill connection shaft 117 . Since it is possible to provide a motion freedom larger than the motion of the wheel 170 , the driver can more smoothly and stably steer the vehicle when changing the driving direction by using the inclination of the vehicle.
[0080] On one hand, the steering unit 100 may include a receiving unit which is able to receive a steering control signal from the control unit 500 , and a plurality of driving force transfer units which are able to transfer the force to rotate the sill connection shaft 117 in response to the received steering control signal.
[0081] On the other hand, the steering unit 100 is able to control the steering link 160 which connects the wheel 170 and the axle of the vehicle and is rotatable leftward or rightward of the driving direction of the vehicle with respect to the direction horizontal to the ground. When controlling the driving direction of the vehicle, the frame 50 including the wheel 170 is inclined leftward or rightward of the driving direction of the vehicle with respect to the direction vertical to the ground in response to the rotation of the sill connection shaft 117 , thus controlling the steering of the vehicle, whereupon the steering of the vehicle can be carried out by rotating the steering link 160 leftward or rightward of the driving direction of the vehicle with respect to the direction horizontal to the ground.
[0082] Meanwhile, it is preferred that the angle that the steering link 160 is able to rotate is above 0° and below 90° with respect to the driving direction of the vehicle.
[0083] Here, the operation where the steering link 160 rotates leftward or rightward of the driving direction of the vehicle with respect to the direction horizontal to the ground will be described in detail with reference to FIG. 6 . Assuming that there may be a virtual surface which is formed horizontal with respect to the ground when it is passing through the center of the vehicle, it means that the steering link 160 disposed in parallel with the corresponding horizontal surface rotates leftward or rightward of the driving direction of the vehicle. Namely, this is basically same as the vehicle steering method of the typical vehicle to steer the vehicle in the leftward or rightward direction.
[0084] As described in the above operation, the present invention aims to provide a system wherein the direction change of the vehicle can be carried out with the aid of the inclination in the vertical direction with respect to the ground or the rotation in the direction horizontal to the ground or provide a system which is able to change the driving direction of the vehicle by controlling all the two inclinations and the rotation.
[0085] The driving unit 300 will carry out a function to drive the vehicle by supplying the driving force from the inside or outside of the vehicle. More specifically, the driving unit 300 will carry out a function to receive a driving control signal from the control unit 500 and a driving force to drive the vehicle and drive the vehicle in response to the received driving control signal.
[0086] Meanwhile, the driving unit 300 may preferably include a receiving unit to receive a driving control signal from the control unit 500 , and a plurality of driving force transfer units which are able to transfer force to drive the wheel 170 connected to the front axle 140 and the rear axle 150 in accordance with the received driving control signal when carrying out the driving control function.
[0087] Moreover, the vehicle may include a driving motor 310 to individually transfer the driving force to each wheel 170 , and an electronic transmission to control the driving motor. The control unit 500 will generate a driving control signal to control the speed of the driving motor 310 connected to each wheel 170 and will transfer the signal to the driving unit 300 , and the driving unit 300 may drive the vehicle in such a way to adjust the speed of each driving motor 310 in response to the received driving control signal. Meanwhile, the driving motor may be connected with a suspension device to support the weight of the vehicle and reduce the up and down vibrations of the vehicle. Different from the conventional configuration wherein the driving force generated by one driving motor 310 is transferred to each wheel 170 of the vehicle via a gear or a shaft, the driving motor 310 is provided at each wheel 170 , thus individually controlling the wheels 170 of the vehicle. If an independent driving control with respect to each wheel 170 is made possible in such a way to provide the driving motor 310 to each wheel 170 , the safety and driving force of the vehicle can be more improved as compared to the conventional driving method. Since the driving force to each wheel 170 can be distributed during the driving, the braking energy recovery due to the recovery braking can be maximized during the braking, whereupon the energy efficiency to drive the vehicle can be maximized. Moreover, If the independent driving control is obtained by providing the driving motor 310 at each wheel, all the power train components which were necessary for the vehicle can be removed, which may result in the simplified structure of the vehicle, and since each wheel 170 can be individually controlled, it is advantageous to effectively adjust the driving, braking and steering of the vehicle.
[0088] Moreover, in a state where the independently operable driving motor 310 is provided at each wheel 170 of the vehicle, the driving unit 300 is able to increase the driving motor 310 of the right wheel 170 of the vehicle while reducing the speed of the driving motor 310 of the left wheel 170 of the vehicle, thus making it possible to turn the driving direction of the vehicle toward the leftward direction. In similar ways, the driving direction of the vehicle can be changed toward the right direction.
[0089] According to the present invention, the driving direction change of the vehicle can be carried out by any of the methods wherein (i) the vehicle is inclined leftward or rightward of the driving direction of the vehicle based on the direction vertical to the ground, (ii) the vehicle can turn leftward or rightward of the driving direction of the vehicle based on the direction horizontal to the ground, and (iii) the driving speeds of the left wheel 170 and the right wheel 170 of the vehicle are adjusted in a state where the driving motor 310 is individually provided at each wheel 170 .
[0090] The configuration of the vehicle which will be controlled according to the present invention will be described with reference to FIG. 2 .
[0091] FIG. 2 is a plane view illustrating a vehicle which equips with a system for controlling the rolling of a vehicle according to an embodiment of the present invention.
[0092] As a main component of the frame 500 to control the driving direction of the vehicle based on the inclination of the vehicle, there are a sill connection plate 110 provided to allow the left and right sills 130 of the vehicle to be supported simultaneously movable, and a sill connection shaft 117 which is able to incline the side sill.
[0093] The sill means a piece member which is able to support the lower side of a predetermined device. The side sill 130 in the vehicle means a member which is provided at the lower end portions of both sides of the vehicle and is able to support the whole weight of the vehicle. A center sill 120 means a member which is provided between the side sills 130 and is able to support the weight at the central portion of the vehicle. Since the key object of the present invention is to change the driving direction of the vehicle by inclining the vehicle body, the side sill 130 and the center sill 120 are preferably provided separates from each other, whereupon each sill can be individually inclined when the vehicle body is inclined.
[0094] Meanwhile, the sill connection plate 110 means a plate which is able to support the side sill 130 . It is a connection plate which may allow the side sills 130 at both sides to be simultaneously inclined when the vehicle is inclined to one side. Since a technology wherein a plurality of members arranged in parallel are connected with one connection plate and are inclined in the same direction in terms of their motions would be easily carried out by a person having ordinary skill in the art, the description thereon will be omitted. An additional metallic member may be added to the sill connection plate 110 , thus enhancing the strength of the connection portion of the side sills 130 .
[0095] Meanwhile, the sill connection plate 110 and the side sills 130 are connected via the sill connection shaft 117 . If the sill connection shaft 117 rotates by receiving the force from the inclination control motor 185 , the left and right side sills 130 will rotate about the sill connection shaft 117 , thus inclining the vehicle. More specifically, the sill connection shaft 117 will rotate in response to a steering control signal of the steering unit, whereby the side sills 130 are inclined, thus controlling the driving direction of the vehicle. Here, the driving force that the sill connection shaft 117 needs to rotate can be generated by the inclination control motor 185 . The transfer of the driving force can be carried out by the sill connection plate 110 .
[0096] The transfer of the driving force to rotate the sill connection shaft 117 may be carried by two methods. The first method is to use the driving force transfer shaft and gear which are provided at the sill connection plate 110 . If the inclination control motor 185 generates driving force in response to a steering control signal, the driving force can be transferred via the driving force transfer shaft and the gear to the sill connection shaft 117 which is connecting the side sills 130 and the sill connection plate 110 . The second method is to provide another axle (a second axle) which is in parallel with the front axle 140 or the rear axle 150 and connect the corresponding axle and the wheel 170 to a joint unit which can be inclined, and transfer the driving force generated by the inclination control motor 185 to the axle. The second method has a difference as compared to the second method in the way that the driving force generated by the inclination control motor 185 is transferred to the joint unit which is connecting each wheel and the second axle. At this time, the function of the joint unit may correspond to the sill connection shaft 117 of the first method, and if necessary, it may be substituted with the sill connection shaft 117 .
[0097] Meanwhile, the vehicle equips with the front axle 140 and the rear axle 150 , and the wheel 170 is provided at both ends of each axle to steer the vehicle as it turns about the shaft and support the weight of the vehicle. According to the embodiment of the present invention, the axle and the wheel 170 may be connected with the steering link 160 being interposed between them. The steering link 160 may include a joint which may rotate in the direction vertical or horizontal with respect to the ground, whereby the vehicle can incline leftward or rightward based on the direction vertical with respect to the ground or can rotate leftward or rightward based on the direction horizontal with respect to the ground.
[0098] Moreover, a steering link control motor 180 is connected to the axle so as to transfer driving force which is able to rotate the steering link (A) 160 when the vehicle changes the driving direction based on the direction horizontal with respect to the ground. The steering link control motor 180 may be connected to the front axle 140 or the rear axle 150 , thus individually controlling the steering link (B) 160 which is connecting the front axle 140 and the wheel 170 . In case where the steering links (A and B) of the front axle 140 and the rear axle 150 are individually controlled, it is possible to greatly reduce the rotation radius as compared to when the vehicle turns by rotating only the steering link (A) 160 of the front axle 140 as in the conventional technology. The movement trajectory of the vehicle may be made to look like a straight line in such a way that the steering links of both the axles are rotated rather than to change the lane by rotating only the steering link of one front axle or one rear axle during the change of the lane. Moreover, it is possible to advantageously reduce any inertial force and instability of the vehicle body which may occur since the vehicle turns along a curved trajectory during the change of the lane.
[0099] For example, if it needs to change the lane of the road, the steering unit 100 steers the steering link connected to the front axle to turn 20° in the leftward direction with respect to the driving direction of the vehicle, and steers the steering link connected to the rear axle to turn 20° in the left direction, whereupon the vehicle can change the lane while moving along a trajectory which looks like a straight line, not a curved line.
[0100] If the vehicle makes a U-turn on the road, the steering unit 100 steers the steering link connected to the front axle to turn 45° in the leftward direction with respect to the driving direction of the vehicle and steers the steering link connected to the rear axle to turn 45° in the rightward direction, whereby the vehicle can make a U-turn along a smaller rotation trajectory as compared to the conventional technology.
[0101] According to another embodiment of the present invention, the wheel 170 may individually equip with a driving motor 310 and an electronic transmission, and each driving motor and electronic transmission are able to individually adjust the driving speed of each wheel 170 in response to a driving control signal generated by the control unit 500 .
[0102] The flows of various control signals according to an embodiment of the present invention will be described with reference to FIG. 3 .
[0103] Referring to FIG. 3 , the steering signal and the driving signal are transmitted from each steering operation mechanism 200 or driving operation mechanism 400 to the control unit 500 , and the control unit 500 will generate a steering control signal or a driving control signal and transmit the generated steering control signal or driving control signal to each steering unit 100 or driving unit 300 .
[0104] The steering operation mechanism 200 is a mechanism which is able to receive the driving direction of the vehicle based on a driver's intention when the driver wants to change the driving direction of the vehicle. As an example, the steering mechanism 200 may be a handle provided in front of the driver. The method that the steering operation mechanism 200 receives the driving direction of the vehicle from the driver is not limited. The steering operation mechanism 200 may include any component as long as it is able to transfer the driver's intention to change the driving direction of the vehicle. Meanwhile, the steering operation mechanism 200 will convert the driving direction input of the vehicle received from the driver into an electrical signal and transfer it to the control unit 500 . The electrical signal may be a PWM (Pulse Width Modulation) signal.
[0105] The driving operation mechanism 400 is a mechanism to receive a driving time, a driving speed, etc. of the vehicle in accordance with the driver's intention when the driver is about to give a command on the driving of the vehicle. It may be, for example, an accelerator which is provided in the driver's compartment. The method that the driving operation mechanism 400 receives the command on the driving of the vehicle from the driver is not limited. The steering operation mechanism 400 may include any component as long as it is able to transfer the driver's command on the driving of the vehicle. Meanwhile, the driving operation mechanism 400 may convert the vehicle driving command received by the driver into an electrical signal and transfer to the control unit 500 . The electrical signal may be a PWM (Pulse Width Modulation) signal.
[0106] Meanwhile, the control unit 500 will carryout a predetermined calculation with respect to the received steering signal or driving signal, thus generating a steering control signal or a driving control signal.
[0107] More specifically, the control unit 500 is able to extract from the received steering signal the data, for example, the driving direction of the vehicle which is supposed to change its driving direction, a turning amount, etc. that the driving direction of the vehicle turns. A steering control signal formed of the driving direction of the vehicle, a vehicle body inclination angle, left and right rotation angles of the steering link 160 , etc. which are necessary when to change the driving direction of the vehicle can be generated based on the extracted data.
[0108] Moreover, the control unit 500 is able to extract from the received driving signal the data, for example, the driving direction of the vehicle, the speed and acceleration of the vehicle, etc., and a driving control signal formed of an information on whether or not the vehicle is currently in the turning section, an output amount necessary for the driving speed and acceleration of the vehicle, the driving speed of the individual wheel 170 necessary for the change of the driving direction of the vehicle, etc. can be generated based on the extracted data.
[0109] Meanwhile, the steering unit 100 will change the driving direction of the vehicle by receiving a steering control signal from the control unit 500 , which will be carried out in such a way that the sill connection plate 117 is rotated, and the vehicle body including the wheel 170 is inclined leftward or rightward of the driving direction of the vehicle based on the direction vertical with respect to the ground, and the steering link 160 is rotated leftward or rightward of the driving direction of the vehicle based on the direction horizontal with respect to the ground.
[0110] Moreover, the driving unit 300 will drive the vehicle by receiving a driving control signal from the control unit 500 , which can be caused in such a way to supply a driving force to one or more than one driving motor 310 . If the driving motor 310 is multiple in number, the driving unit 300 is able to adjust the driving speed of each driving motor 310 while simultaneously changing the driving direction of the vehicle of the steering unit 100 in accordance with the driving control signal, whereupon the change of the driving direction of the vehicle can be more effectively carried out. For example, if the vehicle is intended to turn in the leftward direction, the direction change to the leftward direction can be carried out by the steering unit 100 , and the driving unit 300 will decrease the driving speed of the wheel 170 positioning at the left side of the wheel or increase or maintain the driving speed of the wheel 170 positioning at the right side, whereby the vehicle can be controlled to carry out the turning in the leftward direction.
[0111] FIG. 4 is a view schematically illustrating a connection relationship between the steering operation mechanism 200 , the control unit 500 , the steering unit 100 and the sill connection plate 110 .
[0112] Referring to FIG. 4 , since the steering operation mechanism 200 is directly connected to the control unit 50 , the input on the driving direction of the vehicle can be transferred. At this time, the transferred input signal will be converted into an electrical signal as mentioned previously and will be transferred as a steering signal. The control unit 500 will generate a steering control signal based on the received steering signal and transfer it to the steering unit 100 . The steering unit 100 will transfer a driving force to rotate the sill connection shaft via the sill connection plate 110 based on the received steering control signal, thus rotating the sill connection shaft 117 and controlling the change of the driving direction of the vehicle.
[0113] In the embodiment in FIG. 4 , it was assumed that the turning of the vehicle is carried out in such a way that the driving direction of the vehicle is inclined leftward or rightward of the driving direction of the vehicle based on the direction vertical with respect to the ground. As mentioned above, based on the changing method of the driving direction of the vehicle, the portions that the steering unit 100 can control may be the sill connection shaft 117 , the steering link 160 , etc.
[0114] FIG. 5 is a view illustrating a state where the frame 50 including the wheel 170 is inclined with respect to the direction vertical to the ground during the driving of the vehicle according to an embodiment of the present invention.
[0115] FIG. 7 is a view illustrating a state where the tires are contacting with the ground during the driving of the vehicle according to another embodiment of the present invention.
[0116] As illustrated in FIG. 7 , the vehicle is driven with the threads (the wide portions between the tires and the ground) being contacting with the ground in a state where the tires are not inclined when the vehicle goes straight. Meanwhile, if the vehicle turns left, the tires will go with apart of the thread as indicated by the dotted line in the drawing as well as a part of the side wall (a side surface) of the tires being contacting with the ground.
[0117] Since the portions that the tires are contacting with the ground are different for each driving situation, the wear rates of the tires can be lowered while enhancing resource use efficiency in such a way to minimize the wears of the tires against the ground according to the present invention.
[0118] Meanwhile, each of the tires in general is formed in a semicircular shape wherein a thread has a curvature over a predetermined value. In this case, the area that the thread is contacting with the ground may be more decreased, whereupon it is possible to effectively reduce the wear rates of the tires.
[0119] FIG. 8 is a view for describing the method for controlling the rolling of the vehicle according to the present invention.
[0120] Referring to FIG. 8 , the method for controlling the rolling of the vehicle according to an embodiment of the present invention may include a step S 110 wherein the steering operation mechanism 200 and the driving operation mechanism 400 receive a steering control signal and a driving signal and transfer to the control unit 500 (S 110 ). At this time, the steering signal or the driving signal transferred to the control unit 500 may be electrical signal which have been converted in the steering operation mechanism 200 and the driving operation mechanism 400 , in particular, they may be PWM (Pulse Width Modulation) signals. The control unit 500 may include a step to analyze the received steering signal and driving signal (S 120 ). The above analysis is to extract the information from the steering signal and the driving signal, which may be necessary to change the driving direction of the vehicle or provide a driving command. In particular, if the signal is a PWM signal, the control unit 500 may be able to extract the information in such a way to analyze a rising edge, a falling edge, a delay, etc. of the transmitted signal.
[0121] As a result of the analysis in the step S 120 , the control unit 500 is able to calculate the driving direction of the vehicle, the data which would be necessary to change the driving direction of the vehicle, for example, the turning amount for the sake of the driving direction of the vehicle, and the data which would be necessary to drive the vehicle, for example, the speed of the driving motor 310 . The steering control signal and the driving control signal can be generated based on the calculated data and will be transmitted to the steering unit 100 and the driving unit 300 (S 130 and S 140 ). At this time, the steering control signal may be formed of the driving direction of the vehicle, the vehicle body inclination angle which is necessary to change the driving direction, and the rotation angle of the steering link 160 , etc. The driving control signal may be formed of the information on whether or not the vehicle is currently in the turning section, the output amount necessary for the driving speed and acceleration of the vehicle, and the information, for example, on the driving speed of the individual wheel 170 which is necessary to change the driving direction of the vehicle.
[0122] Meanwhile, after the steering unit 100 receives the steering control signal, the steering unit 100 will control the driving direction of the vehicle in such a way to incline the frame 50 including the wheel 170 of the vehicle leftward or rightward of the driving direction of the vehicle based on the direction vertical to the ground or rotating the steering link 160 leftward or rightward of the driving direction of the vehicle based on the direction horizontal to the ground, both the operations of which can be carried out by controlling the sill connection plate 110 or the steering link 160 in response to the received steering control signal. The driving unit 300 will change the driving direction of the vehicle in such away to adjust the speed of the driving motor 310 connected to the wheel 170 in accordance with the received driving control signal.
[0123] FIG. 9 is a view for describing the method for controlling the rolling of the vehicle according to another embodiment of the present invention.
[0124] FIG. 9 shows the method for controlling the rolling of the vehicle which is able to minimize any instability due to the rotational inertial force of the vehicle during the operation wherein the driving direction of the vehicle is changed based on the direction horizontal to the ground.
[0125] Referring to FIG. 9 , the method for controlling the rolling of the vehicle according to an embodiment of the present invention may include a step S 210 wherein the steering operation mechanism 200 and the driving operation mechanism 400 receive the steering signal and the driving signal and transfer them to the control unit 500 . The control unit 500 will analyze the received signals and will calculate the data to change the driving direction of the vehicle and the data which are necessary for the driving of the vehicle and will generate a steering control signal and a driving control signal based on the calculated data and transfer them to the steering unit 100 and the driving unit 300 (S 220 ).
[0126] According to an embodiment of the present invention, the steering unit 100 will control the driving direction of the vehicle by rotating the steering link 160 leftward or rightward of the driving direction of the vehicle based on the direction horizontal to the ground in according to the received steering control signal (S 230 ). More specifically, the present invention is directed to the method for controlling the rolling of the vehicle so as to reduce any instability which might occur due to the rotational inertial force or the centrifugal force when the vehicle is turning in the horizontal direction.
[0127] Meanwhile, when the driving direction of the vehicle is being changed in the above manner, the sensor unit may include a step S 240 to detect the vehicle state information of the vehicle and transmit it to the control unit 500 . The vehicle state information may be formed of the rotational inertial force of the current vehicle, the angle that the vehicle has inclined due to the turning of the vehicle, the acceleration of the vehicle and the level of the centrifugal force. Here, the centrifugal force means an inertial force that in general generates at the turning vehicle and has the same size as the centripetal force and the opposite direction to it. The centrifugal force has a force which is applying in the direction where it moves away from the center of the rotational radius. The unit of the centrifugal force size is N (Newton) or dyn.
[0128] Meanwhile, the control unit 500 may include steps S 250 to 270 wherein a steering control signal is generated by calculating the compensation value with respect to the vehicle state information, and the steering unit 100 will adjust the inclination of the vehicle by controlling the sill connection plate. At this time, the compensation value means a predetermined value to minimize any instability of the vehicle during the change of the driving direction of the vehicle, more specifically, a value to minimize any change in the inclination of the vehicle due to the centrifugal force. According to the present invention, even though any instability factor occurs during the change of the driving direction of the vehicle, the method for controlling the rolling of the vehicle is able to minimize such an instability factor according to an embodiment of the present invention.
[0129] The invention has been described in detail with reference to preferred embodiments thereof. However, it will be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents. | A system for controlling rolling of a vehicle and a method therefor, the system comprising: a control unit for receiving and analyzing a steering signal and a driving signal from a driver of a vehicle having a frame by which the gradient of the vehicle during traveling can be controlled and generating a steering control signal and a driving control signal on the basis of a result value according to the analysis; and a steering unit and a driving unit for controlling a traveling direction and driving of the vehicle according to the steering control signal and the driving control signal received from the control unit, respectively. | 1 |
FIELD OF THE INVENTION
This invention relates to the area of fire arms, and more specifically, disabling small arms in the field. The device described herein renders a small arm such as a rifle, pistol, or other weapon, incapable of chambering or firing a round of ammunition.
BACKGROUND OF THE INVENTION
In times of war, during port or shipboard inspections, and police actions, the military, Homeland Security, or Customs Security Officers are often confronted with the need to carry off, guard, disable, or destroy illegally imported or captured weapons, particularly small arms. The need may arise when weapons are seized individually, or when the weapons are located in stockpiles, caches or shipping containers. While guarding the captured weapons is an option, guarding is manpower intensive and occupies the time of a well trained soldier, Customs, or Homeland Security Officer who's skills and training may be better used elsewhere. Often, the weapons must eventually be disposed of in some manner, often at yet another location, requiring further manpower to guard, transport, and destroy the weapon.
While small arms can be rendered inoperable by application of force, such as crushing, or by the application of sufficient heat to melt or bend the working components of the weapon, equipment, facilities, skills, and manpower are often unavailable to use these methods in battlefield conditions, aboard ships, or at Ports of Entry. Thus, the need exists to easily disable small arms with the limited manpower, limited skills, and limited equipment typically available under conditions found in the field, or at Ports of Entry.
SUMMARY OF THE INVENTION
The invention disclosed herein is a field tool to render inoperable or deactivate small arms. In the most preferred embodiment, the invention is a single use injection device similar to a syringe that allows a user to place a bonding material such as an adhesive or epoxy into the barrel, breach, receiver, or other working parts of the weapon. Once in place, the bonding material can interfere with the operation of the firing pin, extractor, bolt, magazine, and other moving components of the weapon, as well as physically occupying or plugging the breach or barrel of the weapon so that a round cannot be chambered. Further, the field tool can be left in the barrel of the weapon after use and thus bonded in place, providing a ready indicator that the weapon has been rendered inoperable.
The field tool or applicator is readily transportable and simple to operate, thus allowing the device to be carried into the field and used by personnel with minimal training. The use of the device involves clearing the weapon of ammunition, placing an empty magazine into the receiver, moving the bolt to close the breach of the weapon, inserting the applicator into the muzzle of the weapon until the bolt face is in contact with the applicator, and pushing the plunger to dispense the bonding material into the workings of the weapon. Should the bolt be missing from the weapon, or not in the closed position, the device can still be used, however the performance may be diminished.
Similarly, the device will also work without the magazine being in place. If the magazine is not in place, the bonding material can still seep into the receiver, thereby obstructing insertion of a magazine. Even if a magazine can be inserted, the bonding material may also foul or bind the magazine locking mechanism so that the magazine cannot remain in the receiver. This obstructing and binding can occur in addition to the obstruction of the breach and fouling and bonding of other parts the weapon.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram showing a small arm and a cross-sectional view of the field tool of the present invention.
FIG. 2 is an end elevational view of the nozzle end of the field tool.
FIG. 3A is a cross-sectional view of a small arm with the field tool inserted into the barrel of the weapon.
FIG. 3B is a close-up cross-sectional view of the field tool in the breach end of the weapon.
FIG. 4A is a cross-sectional view of the small arm with the field tool inserted into the barrel, the field tool partially dispensing material into the workings of the weapon.
FIG. 4B is a close-up view of the field tool dispensing material into the barrel and around the bolt of the small arm.
FIG. 5A is a cross-sectional view of the small arm with the field tool inserted into the barrel, the field tool having dispensed product into the workings of the small arm.
FIG. 5B is a close-up view of the field tool completing dispensing of the material into the barrel of the small arm.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
As shown in the Figures, the field tool 10 of the preferred embodiment is a generally cylindrical casing 20 preferably having a wall thickness of approximately two hundredths of an inch thick. The casing 20 is approximately three inches long. The casing 20 includes a port or nozzle 21 at a first end 23 , and an opening to accept a plunger 25 at a second end 24 , the plunger 25 extending coaxially and slidably within the casing 20 . When the plunger 25 slides toward the nozzle 21 , material 50 is dispensed out of the nozzle 21 . The nozzle 21 is approximately 0.0625 inches in diameter. The casing 20 is approximately 0.2 inches in diameter, to allow the casing to fit into the barrel of weapons as small as .22 caliber.
One skilled in the art will recognize that larger diameter casings can be used for larger caliber weapons. For instance, the casing is preferably 0.3 inches in diameter when designed for use with .40-.50 caliber weapons. The larger diameter casing 20 allows more material to be injected into the larger caliber weapons, and reduces the clearance between the wall of the casing 20 , and the wall of the barrel 61 . Additionally, one will recognize that the dimensions set forth herein are only preferences and may be varied.
The first end 23 of the casing 20 also includes stand-offs 40 a - c , which extend beyond the opening of the nozzle 21 by approximately 0.04 inches. The stand-offs 40 a - c may extend beyond the nozzle 21 by other amounts. Although the preferred embodiment shows three stand-offs, one skilled in the art will recognize that the number of stand-offs can vary, so long as the structure displaces the nozzle 21 from the bolt face 70 . The stand-offs 40 a - c are placed against the bolt face 70 when the field tool 10 is inserted into the barrel 61 of a small arm 60 , as shown in FIGS. 3A-5A . The stand-offs 40 a - c allow the nozzle 21 to be displaced from the bolt face 70 , allowing material 50 to freely flow out of the nozzle 21 and into the workings of the small arm 60 . The displacement from the bolt face 70 also allows the material 50 to occupy the space between the bolt face 70 and the nozzle 21 , thereby forming a plug of material 50 . The plug of material 50 will remain in the barrel 61 even if the field tool 10 is removed from the barrel 61 .
The plunger 25 includes a plunger first end 26 and a plunger second end 27 . Between the plunger first end 26 and the plunger second end 27 is a circumferential groove 30 which engages a circumferential bulge 35 that extends inwardly from the wall of the casing 20 into the interior of the casing 20 . One skilled in the art will recognize that the groove 30 and protrusion 35 need not extend about the entire circumference of the casing 20 or plunger 25 . When so engaged, the plunger 25 is fixed in position relative to the casing 20 and movement of the plunger 25 within the casing 20 is restrained, unless sufficient force is applied to overcome the engagement. Plunger 25 also includes an area of reduced diameter 37 , which allows the plunger 25 to pass by the circumferential protrusion 35 when the field tool 10 is activated by applying force to move the plunger 25 toward the nozzle 21 .
The material 50 dispensed through nozzle 21 when plunger 25 is pushed forward can be a two part epoxy that will mix as the plunger 25 is moved towards the nozzle 21 . Such two part epoxies typically have a resin and activator or hardener that activate when mixed together. Such two part epoxies are manufactured by J-B Weld Company of Sulpher Springs Tex. The epoxies are available in a number of formulations having different working times, and bonding properties. Those having superior bonding to metal surfaces are preferred. Resistance to solvents is also preferred to hamper cleaning or repair of the deactivated weapon. It is preferred that the epoxy have a working time of 30 minutes or less. In alternate embodiments, the material 50 may be a single part bonding material such as a polyurethane adhesive, which will not need mixing.
One part of the epoxy, typically the hardener, can be encased in glass or plastic beads, the beads being suspended in the second part, or resin. Alternatively, each part of a two part epoxy can be encased or suspended in plastic or glass structures such as packets, tubes, beads, or other suitable structures that will keep the parts separated prior to use. Such structures however, must rupture or otherwise allow the two parts of the binary material to mix when the plunger 25 moves towards the nozzle 21 . One skilled in the art will recognize arrangements other than glass or plastic beads can be used to store and activate binary materials in the present invention.
In operation, as shown in FIG. 3A through 5B , the field tool 10 is inserted nozzle 21 first into the barrel 61 of the weapon 60 by way of the muzzle 62 . The plunger 25 of the field tool 10 is typically 30 inches in length, to accommodate common barrel lengths of standard small arms, typically of 28-30 inches. One skilled in the art will recognize that other length plungers 25 can be used to accommodate weapons with shorter or longer barrels.
As shown in FIG. 3 , the field tool 10 is inserted into the barrel 61 so that the stand-offs 41 a - 41 c rest against the bolt face 70 . The plunger second end 27 extends out the muzzle 62 of the barrel 61 . To use the field tool 10 , the plunger second end 27 is pressed in the direction of arrow 55 , which is a direction towards the nozzle 21 . Such force dislodges circumferential groove 30 from the circumferential protrusion 35 , allowing the plunger first end 26 to force material 50 out of nozzle 21 , and into the barrel 61 of the small arm 60 .
As the material 50 exists nozzle 21 , it backfills into the barrel 61 , and penetrates around the bolt 69 and into the receiver area of the weapon 60 , wherein the material 50 contacts other workings of the weapon 60 , and will lock the bolt 69 in place, preventing removal of the bolt 69 or movement of the bolt 69 or chambering of a round of ammunition. The material 50 may also inhibit the operation of the firing pin 75 within bolt 69 and may also interfere with extractors and other components of the bolt 69 .
If a magazine 66 is in the weapon or small arm 60 , the material can enter the magazine 66 , or the magazine locking mechanism, preventing removal of the magazine 66 from the small arm 60 . While it is preferred an magazine 66 is in the weapon prior to the use of the field tool 10 , if a magazine 66 is not present, the material 50 can still interfere with the magazine locking mechanism such that a magazine 66 cannot be inserted into or retained in the small arm 60 .
As shown in FIG. 5 , the plunger 25 is advanced through to the end of the area of reduced diameter 37 , wherein further movement of the plunger 25 is restricted by circumferential protrusion 35 , which does not allow the wider portion of the plunger 25 to pass. This limitation in movement prevents the plunger 25 from completely ejecting material 50 from the casing 20 . The material 50 remaining within the casing 20 , and extending out through the nozzle 21 mechanically fixes or adheres the casing 20 in the barrel 61 when material 50 hardens. Further, the first end 26 of the plunger 25 can include an area of reduced diameter 57 which can fill with material 50 as plunger 25 is advanced into the casing 20 . This area provides mechanical adhesion so that plunger 25 cannot be removed from casing 20 when material 50 hardens.
The method and structure described herein are merely examples of how the invention can be constructed and used. Such examples are not meant to limit the scope of the invention. | A device and method for deactivating firearms is described herein. The device includes a casing having a nozzle and a plunger for dispensing a bonding material out of the nozzle. The device is inserted into the barrel of a weapon, and the material is injected into the barrel near the bolt face of the weapon. The bonding material enters the working mechanism of the firearm and hardens, interfering with operation of the firearm. | 5 |
BACKGROUND OF THE INVENTION
This invention relates to a method of producing a so-called glazed ceramic substrate by forming a glass coating layer on a major surface of a ceramic substrate by firing the substrate and then cooling the substrate to allow the molten glass layer to turn into a solid coating layer.
Recently there has been an increasing trend to glaze a major surface of a ceramic plate, such as alumina plate, in order to utilize the glazed ceramic plate as a substrate of an electric or electronic device. A ceramic substrate having a glass coating is commonly called a glazed ceramic substrate and features high smoothness of its glazed surface besides the favorable characteristics of the ceramic substrate such as high stability at high temperatures and good workability.
At present glazed ceramic substrates are largely used in manufacturing hybrid integrated circuits. Each glazed ceramic substrate for this use is relatively small in size, and the glass coating of the glazed ceramic substrate is not required to be highly heat-resistant. Therefore, it is not so difficult to select a glass composition suitable as the coating material, that is, to select a glass which can readily be fused onto a ceramic substrate at a relatively low heating temperature and is low in the content of alkali metals, which are unfavorable for the electric characteristics of the coating layer, and comparable in the coefficient of thermal expansion to the ceramic substrate. The comparableness in thermal expansion coefficient between the glass and the ceramic is desired from the viewpoint of obtaining a glazed ceramic substrate high in flatness without suffering from warping of the substrate subjected to cooling from a high temperature during the glazing procedure.
Meanwhile, there is a increasing trend to use glazed ceramic substrates in manufacturing thermal heads of thermal printing devices. Glazed ceramic substrates for this use are generally required to be very high in stability and durability of their glass coating layers at considerably high temperatures, and accordingly it becomes preferable to employ a glass composition which features highness of its transition point as the coating material. Then it becomes difficult to meet the desire of using a glass of which coefficient of thermal expansion is close to that of the ceramic substrate to be coated with the glass, and consequentially warping of the substrates subjected to the glazing procedure becomes a serious problem in industrial production of glazed ceramic substrates having satisfactory high-temperature characteristics. This problem is further augmented by the fact that relatively large-sized substrates are needful for thermal heads.
There is a possibility of suppressing warping of a glazed ceramic substrate by increasing the thickness of the ceramic substrate to be coated with glass, but this method is hardly practicable because it places great restrictions on the design of the thermal heads. For a similar reason, it is also difficult to employ a specific ceramic material which is comparable in thermal expansion coefficient to the glass having desirable high-temperature characteristics.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an improved method of producing a glazed ceramic substrate, the product of which method is high in flatness and practically free from warping even when there is a considerable difference in thermal expansion coefficient between the ceramic material of the substrate and the glass employed as the coating material.
A method according to the invention for the production of a glazed ceramic substrate has the steps of applying a glass onto a major surface of a plate-shaped ceramic substrate, firing the glass-applied substrate at a temperature above the melting temperature of the glass to thereby form a molten glass layer on the substrate, and cooling the fired substrate to allow the molten glass layer to turn into a solid coating layer. During the firing and cooling steps, the substrate is placed on a refractory base. The improvement according to the invention resides in that the refractory base is so shaped as to allow the substrate to deform during the firing step such that the deformation offsets against warping of the substrate attributed to a difference between the coefficient of thermal expansion of the glass coating and that of the ceramic substrate during the cooling step.
In the present invention it is premised that warping of the glass-coated ceramic substrate during the cooling step is inevitable, and, instead of trying to suppress the warping at the cooling step, it is contrived to let the substrate reversely deform during the firing step by using an appropriately shaped refractory base to support the substrate thereon so that the warping deformation at the cooling step may have the effect of just redressing the preceding deformation of the substrate. By this contrivance, the invention has succeeded in producing a glazed ceramic substrate with very high flatness even when use is made of a glass of which coefficient of thermal expansion is not close to that of the ceramic substrate.
Basically, the refractory base for use in the method of the invention has a continuous and curved upper surface, and the curvature of this surface is such that almost an entire area of the ceramic substrate placed on the base is spaced from the curved upper surface while the substrate remains flat but comes into contact with the curved upper surface when the substrate deforms during the heating step. In most cases the upper surface of this base is a concave surface because usually the coefficient of thermal expansion of the ceramic substrate is greater than that of the glass coated thereon and, therefore, deformation of the substrate during the firing step renders the bottom face of the substrate convex. However, there is a possibility tht the coefficient of thermal expansion of the ceramic substrate is smaller than that of the glass applied thereto, and in that case the upper surface of the base is shaped into a convex surface.
As an economically favorable modification, the refractory base in the method of the invention may consist of a flat base plate and a plurality of rib-like or pillar-like spacers, which are placed on the top face of the base plate so as to be spaced from each other and each of which has a suitably curved surface.
Other than the use of a refractory base shaped in the above summarized manner, each step of the method according to the invention can be performed in a known way. For example, the initial step of applying a glass onto a major surface of a ceramic substrate can be performed by applying a paste containing a powdered glass onto the substrate surface by utilizing the technique of screen-printing, or by placing a green sheet containing a powdered glass on the substrate surface.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1(A) is a schematic and sectional view of an unfinished glazed ceramic substrate at a heating stage in a conventional production method;
FIG. 1(B) explanatorily shows the manner of warping of a glazed ceramic substrate at the end of a cooling stage in the conventional production method;
FIG. 2 is a perspective and explanatory illustration of a curved base for use in a method according to the invention;
FIGS. 3(A), 3(B) and 3(C) explanatorily illustrate the manner of temporary deformation of an unfinished glazed ceramic substrate and spontaneous redressing of the temporary deformation in a method according to the invention;
FIGS. 4 and 5 show an exemplary design of the curved surface of a base of the type as shown in FIG. 2;
FIG. 6 is a perspective and explanatory illustration of a set of rib-like spacers as parts of a base that is a simplified modification of the base of FIG. 2;
FIGS. 7(A) and 7(B) explanatorily illustrate the use of a base including the spacers of FIG. 6 in a method according to the invention;
FIG. 8 is a schematic plan view of a still simplified base for use in a method according to the invention; and
FIGS. 9(A) and 9(B) explanatorily illustrate the use of the base of FIG. 8 in a method according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A typical and industrially profitable method of forming a glass coating layer on a major surface of a plate-shaped ceramic body is a printing-firing method, which has the steps of applying a paste containing a powdered glass onto the surface of the ceramic body usually by utilizing the technique of screen-printing so as to form a paste layer of a uniform thickness, drying the printed paste layer to dissipate the liquid component of the paste, firing the paste-applied ceramic body so as to melt the glass contained in the printed paste layer, and thereafter cooling the fired body to allow the molten glass layer to turn into a solid coating layer. The firing temperature and the firing time are so determined as to obtain the coating layer with high smoothness of the surface.
The paste is a uniform dispersion of a finely powdered glass in a liquid vehicle, usually an organic liquid material. A preferred example of useful organic liquid materials is terpineol. Optionally, the paste may additionally contain an organic polymeric substance that serves as a viscosity adjusting agent, such as ethyl cellulose for example.
To form a glass coating layer with a uniform thickness, the plate-shaped ceramic body or unfinished glazed ceramic substrate is held horizontally during the firing and cooling steps in the above described method. Referring to FIG. 1(A), at the firing step in a conventional firing-printing method, a plate-shaped ceramic body or ceramic substrate 12 is placed on a supporting plate or base 10 of a refractory material having a flat upper surface 11. The bottom face 13 of the ceramic substrate 12 is in close contact with the flat surface 11 of the base 10, and the upper face of the ceramic substrate 12 is covered with a molten glass layer 14A. At the subsequent cooling step both the ceramic substrate 12 and the glass layer 14A, which is solidifying, undergo some shrinkage. If the coefficient of thermal expansion of the glass is not sufficiently close to that of the ceramic substrate 12, the shrinkage results in warping of the substrate. When the coefficient of thermal expansion of the ceramic substrate 12 is greater than that of the glass coated thereon, the ceramic substrate 12 undergoes greater degree of shrinkage than the glass layer and, as shown in FIG. 1(B), warps such that the bottom face 13 thereof, i.e., bottom face of a glazed ceramic substrate 20 obtained at the end of the cooling step, becomes a concave surface whereas the solidified glass layer 14 becomes convex. The degree of the warping can be expressed by the vertical distance d S of the concave surface 13 of the glazed ceramic substrate 20 from the flat upper surface 11 of the base 10. This distance d S becomes maximal in a central region of the concave surface 13.
FIG. 2 shows a refractory base 30 for use in a method according to the invention in place of the flat base 10 in FIGS. 1(A) and 1(B) for the purpose of preventing the glazed ceramic substrate from warping in the manner as shown in FIG. 1(B). The upper side of this base 30 is shaped into a concave surace 31 which is symmetrical, or approximately symmetrical, to the concave bottom surface 13 of the glazed ceramic substrate 20 in FIG. 1(B) with respect to a horizontal plane. In other words, the upper surface 31 of this base 30 is concaved so as to become a mirror image of the concaved bottom surface 13 in FIG. 1(B), if not optically exactly.
FIGS. 3(A) to 3(C) illustrate an embodiment of a glazing method according to the invention, wherein the ceramic substrate 12 and the glass used for glazing are identical with the counterparts in FIG. 1(A). Referring to FIG. 3(A), at the start of the firing step the ceramic substrate 12 coated with an unfired glass layer 14B is horizontally placed on the refractory base 30 of FIG. 2. Since the upper surface 31 of the base 30 is concaved in the above described manner, the ceramic substrate 12 makes contact with the concave surface 31 of the base 30 only at the four corners of its bottom face 13. In this state, the substrate 12 is heated together with the glass layer 14B to a temperature above the melting temperature of the glass and maintained at that temperatures for a sufficient period of time.
Referring to FIG. 3(B), the heating causes the ceramic substrate 12 to somewhat soften and undergo a deformation while the glass layer 14B in FIG. 3(A) turns into a molten glass layer 14A. As a result, the substrate 12 tends to deform into a convex shape on its bottom side and concave on its top side since the bottom face 13 of the substrate 12 is initially spaced from the upper surface 31 of the base 30. By the end of the firing step, the convex bottom face 13 of the ceramic substrate 12 comes into close contact with the concave surface 31 of the base 30. Thus, the deformation of the ceramic substrate 12 at this stage is reverse of the warping of the same substrate 12 at the cooling stage in the conventional method illustrated in FIG. 1(B).
At the cooling step for solidification of the molten glass layer 14A, the ceramic substrate 12 tends to warp so as to become concave on its bottom side and convex on its top side, but, as shown in FIG. 3(C), in the illustrated method according to the invention the warping of the ceramic substrate 12 at the cooling stage does not actually result in such a manner of warping as shown in FIG. 1(B) and, instead, results in recovery from the deformed state shown in FIG. 3(B). That is, the warping of the ceramic substrate 12 or the finished glazed ceramic substrate 20 at the cooling step completely offsets the intentional and reverse deformation of the substrate 12 at the heating step. Therefore, the glazed ceramic substrate 20 produced by this method is excellent in its flatness. When the ceramic substrate 12 in FIGS. 1(A) and 1(B) is a rectangular plate of alumina 100 mm wide and 300 mm long, the glazed ceramic substrate produced by using the flat base 10 warps lengthwise to the extent of about 2 mm (expressed by the maximal value of distance d S ) and also widthwise to the extent of about 0.5 mm. When the same ceramic substrate 12 is glazed by using the concave base 30 in the way as illustrated in FIGS. 3(A) to 3(C), the ultimate deformation of the glazed ceramic substrate becomes less than 0.2 mm either lengthwise or widthwise.
Referring again to FIG. 3(A), the degree of concaveness of the upper surface 31 of the base 30 is expressed by the depth d B of the concave surface 31 from the flat bottom 13 of the ceramic substrate 12 placed on the base 30. Actual values of the depth d B are experimentally determined prior to shaping of the base 30 with respect to a combination of a ceramic substrate and a glass employed to produce a glazed ceramic substrate. As a basic experiment, the ceramic substrate supported only at its two opposite side ends is heated at temperatures in a range suitable for glazing operations for a certain period of time to examine variations in the degree of deformation of the substrate with the heating temperature and heating time. As a more practical experiment, the ceramic substrate is glazed by using a flat base as shown in FIGS. 1(A) and 1(B) to measure actual values of the distance d S in FIG. 1(B) in various regions of the glazed substrate. Then the upper surface 31 of the base 30 is shaped such that in every region of the ceramic substrate placed on this surface 31 the depth d B in FIG. 3(A) nearly agrees with the distance d S in FIG. 1(B).
Strictly speaking, also thermal deformation of the base 30 itself should be taken into consideration in determining the shape of the upper surface 31. In practice, however, it is possible to dispense with such a strict consideration by using a refractory material having a sufficiently small coefficient of thermal expansion as the material of the base 31. In this regard, silicon carbide is a particularly suitable material. Thermal deformation of the base 31 made of silicon carbide is negligibly small compared with 0.1-0.2 mm deformation of the glazed ceramic substrate.
The ceramic substrate for use in a method of the invention can be selected from conventional ceramic plates prepared as ceramic substrates for electric or electronic devices. For example, alumina, beryllia, magnesia, steatite, forsterite and zirconia can be named as useful ceramic materials.
The glass as the coating material in a method of the invention is not specifically limited. In conventional methods of producing glazed ceramic substrates it is usual to use a lead glass containing SiO 2 and PbO as its principal components, and the same glass is of use also in the present invention. However, it is advantageous to use a glass composition containing, by weight, 50-60% of SiO 2 , 10-30% of Al 2 O 3 , 15-30% of CaO and MgO, and 2-6% of ZrO 2 as essential components, optionally with the addition of small amount(s) of at least one of TiO 2 , BaO, ZnO, PbO, P 2 O 5 , B 2 O 3 , Na 2 O and K 2 O. The particulars of this glass are disclosed in our copending application. This glass is high in transition point and, hence, is excellent in high-temperature stability, and this glass is highly resistant to chemicals.
EXAMPLE
A granular glass composed of 56 parts by weight of SiO 2 , 14 parts by weight of Al 2 O 3 , 4 parts by weight of ZrO 2 , 22 parts by weight of CaO, 2 parts by weight of MgO and 2 parts by weight of B 2 O 3 was pulverized into a fine powder by using a ball mill. A paste was prepared by mixing 100 parts by weight of the powdered glass with a solution of 1.5 parts by weight of ethyl cellulose in 50 parts by weight of terpineol. This paste was applied onto a major surface of a rectangular substrate of alumina (Al 2 O 3 purity 96%), which was 100 mm wide, 300 mm long and 2 mm thick, by screen-printing to form a paste layer with a uniform thickness, and the paste layer was dried at about 100° C. for 1 hr to evaporate the terpineol contained in the paste. The coefficient of linear expansion of the alumina substrate was 70×10 -7 /degree (0°-800° C.), and that of the glass was 55×10 -7 /degree (0°-770° C.).
The thus treated alumina substrate was placed on a base shaped in the manner as shown in FIG. 2. The particulars of the concave surface 31 of this base are shown in FIGS. 4 and 5. Widthwise of the base 30, as shown in FIG. 4, the upper surface 31 was curved approximately parabolically and symmetrically about a horizontal line parallel to the longitudinal central axis of the base 30. Lengthwise of the base 30, as shown in FIG. 5, the upper surface 31 was more greatly curved approximately parabolically and symmetrically about a horizontal line parallel to the lateral central axis of the base 30. Accordingly, the concave surface 31 of this base 30 was a compound of two crosswise intersecting surfaces both of which are parabolically concave though different in curvature.
The base and the alumina substrate were heated in air to a temperature of 1400° C. and maintained at this temperature for 60 min to result in that the top face of the alumina substrate was uniformly coated with a molten glass layer and that the bottom face of the substrate came into close contact with the concave surface of the base. Thereafter the base and the substrate placed thereon were let cool down to room temperature to cause the molten glass layer on the alumina substrate to turn into a solid glass layer.
The glazed ceramic substrate obtained upon completion of cooling was very high in its flatness. Numerically, a deviation from an ideal flatness was less than 0.1 mm in every region of this substrate. At the screen-printing step the thickness of the paste layer was controlled such that the solidified glass coating layer had a thickness of 100 μm. The surface roughness of the coating layer was measured to be below 0.5 μm, meaning that the surface of this coating layer was remarkably high in smoothness. The transition point of the glass employed in this example was 770° C. As will be understood from such a high value of the transition point, the glazed ceramic substrate produced in this example was excellent in high-temperature stability, too. Accordingly this glazed ceramic substrate was evaluated as fully serviceable for a high-performance thermal head.
The curved base 30 of FIG. 2 can be modified in the manner as shown in FIGS. 6, 7(A) and 7(B) with little difference in effect. The modified base consists of a flat base plate 34 and a plurality of rib-like spacers 32A, 32B, 32C, 32D which are placed on, and usually fixed to, the top face of the base plate 34 in a spaced and parallel arrangement. As illustrated in FIG. 6, the rib-like spacers 32A, 32B, 32C, 32D can be regarded as to be obtained by vertically slicing the base 30 of FIG. 2. Accordingly, the upper surface of each of these spacers 32A, 32B, 32C, 32D is a concave surface 33A, 33B, 33C, 33D which becomes a part of the concave surface 31 of the base 30 of FIG. 2.
On the base plate 34, the rib-like spacers 32A, 32B, 32C, 32D are arrayed at nearly equal intervals such that an imaginary surface given by smoothly connecting the concave surfaces 33A, 33B, 33C, 33D of all the spacers becomes a concave surface corresponding to the surface 31 of the base 30 of FIG. 2. When the ceramic substrate 12 is placed on the base of FIG. 7(A), only two spacers 32A, 32D located at the two opposite side ends of the base plate 34 make contact with the bottom face 13 of the substrate 12. Heating of the ceramic substrate 12 to fire the glass layer 14B is commenced in this state, and during the heating the substrate 12 deforms in the manner as shown in FIG. 7(B). As a result, the bottom face 13 of the substrate 12 comes into close contact with the concave surfaces 33A, 33B, 33C, 33D of all the spacers 32A, 32B, 32C, 32D. At the subsequent cooling stage, the substrate undergoes a warp reverse to the deformation at the heating stage and consequentially recovers from the deformed state of FIG. 7(B).
The total number of the rib-like spacers in each base can be made very small, and also the width of each spacer can be made narrow. For example, in the case of a base for a 100 mm wide and 300 mm long substrate it suffices to use four rib-like spacers each of which is 3-10 mm in width.
From an industrial point of view, the modified base shown in FIGS. 6, 7(A) and 7(B) is very advantageous because the total area of the curved surfaces 33A, 33B, 33C, 33D of this base is far smaller than the area of the curved surface 31 of the base 30 of FIG. 2 and, therefore, it is possible to greatly reduce the labor cost for shaping the curved surface.
Depending on the size of the ceramic substrate to be glazed and also on the degree of deformation of the substrate during glazing, there is a possibility of further simplifying the base of FIG. 7(A) by omitting the intermediately positioned spacers 32B and 32C. In that case, the height of the remaining two spacers 32A and 32D are adjusted such that the bottom face of the substrate deformed during the heating process comes into contact with the top face of the flat base plate 34 in its central region.
Sometimes, a further simplification is possible as illustrated in FIGS. 8, 9(A) and 9(B). In this case, the base consists of the flat base plate 34 and four pieces of low, pillar-like spacers 36A, 36B, 36C and 36D which are placed on the top face of the base plate 34 in its four corner regions, respectively. The upper surface of each of these spacers 36A, 36B, 36C, 36D is a curved surface 37A, 37B, 37C, 37D which becomes a part of the concave surface 31 of the base 30 of FIG. 2. Heating of the ceramic substrate 12 to fire the glass layer 14B is commenced by placing the substrate 12 on these spacers 36A, 36B, 36C, 36D as illustrated in FIG. 9(A). During the heating the substrate 12 deforms in the manner as shown in FIG. 9(B) to result in that a central region of the bottom face 13 of the substrate 12 comes into contact with the top face of the flat base plate 34, but at the subsequent cooling stage the substrate recovers from the deformed state to turn into a glazed ceramic substrate with good flatness. This base can be manufactured at a far lower cost than the base of FIG. 7(A). Furthermore, it is possible to shape the upper surface of each of these pillar-like spacers 36A, 36B, 36C, 36D into a slant and flat surface instead of the aforementioned curved surface 37A, 37B, 37C, 37D. When the substrate 12 and the base plate 34 in FIGS. 8 and 9(A) are considerably elongate ones, it is suitable to place an additional pillar-like spacer (not shown) at the middle between the spacers 36A and 36B, and another pillar-like spacer (not shown) at the middle between the spacers 36C and 36D. | A method of producing a glazed ceramic substrate, which is useful for a hybrid integrated circuit or a thermal head of a thermal printer for instance, by applying a glass onto a major surface of a ceramic substrate, firing the substrate to form a molten glass layer on the substrate surface and cooling the fired substrate. To obtain the glazed ceramic substrate with high flatness despite the tendency of the substrate to warp due to difference in thermal expansion coefficient between the ceramic and the glass, a refractory base which supports the substrate during the firing and cooling steps is so shaped as to allow the substrate to deform during the firing step reversely to the expected warp at the cooling step, so that the warp at the cooling step is offset by the preceding deformation. For example, the upper surface of the base is shaped into a continuous and concave surface. As a modification, suitably shaped rib-like or pillar-like spacers are arranged on the top face of a flat base plate with intervals therebetween. | 7 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to an optical disk device that uses a laser or other such light source to reproduce signals on an information carrier (including various kinds of information carrier, such as those used only for reproduction and those used for both recording and reproduction), and more particularly to an optical disk device having a tracking control means for controlling a light spot so that it will accurately scan a track. The present invention also relates to a loop gain setting method and a loop gain setting program with which the loop gain of tracking control is set.
[0003] 2. Background Information
[0004] Digital versatile disks (hereinafter referred to as DVDs) have gained prominence in recent years as high-density optical disks that allow a large quantity of digital information to be recorded.
[0005] FIG. 5 is a schematic of the structure of a DVD-RAM, which is an example of a high-density optical disk. FIG. 5 a is an overall diagram of an optical disk 506 . The optical disk 506 is made up of two different doughnut-shaped regions (regions 1 and 2) separated in the radial direction of the disk. Each of these regions has a plurality of tracks. Region 2 has a phase-change film and allows the optical recording or reproduction of information (hereinafter referred to as the RAM region).
[0006] FIG. 5 b is a cross section of the optical disk 506 , cut radially in the RAM region. As shown in FIG. 5 b , tracks which are continuous guide grooves are formed at a specific spacing on the substrate surface in the RAM region. These tracks have a pitch of about 1.6 μm. In addition, in this RAM region, convex grooves (hereinafter referred to as groove tracks) and portions sandwiched between these groove tracks (hereinafter referred to as land tracks) are both used as tracks for the recording or reproduction of information.
[0007] Meanwhile, in region 1, pits are formed in the tracks by interrupting the grooves. Region 1 is a reproduction-only region in which information is prerecorded by means of these pits (hereinafter referred to as the ROM region).
[0008] FIG. 5 c is a cross section of the optical disk 506 , cut radially in the ROM region. As shown in FIG. 5 c , the track pitch is about 0.8 μm in the ROM region.
[0009] With a conventional optical disk device, in order to perform stable tracking control of the optical disk 506 during the reproduction or recording of information, the tracking control is performed by switching between tracking error signal detection methods for the RAM region and the ROM region (see, for example, Japanese Laid-Open Patent Application H10-124900 (paragraphs 0022 to 0046, FIGS. 1 to 5)).
[0010] A conventional optical disk device will now be described in which tracking control is performed by switching between tracking error signal detection methods in the RAM region and in the ROM region.
[0011] FIG. 6 is a block diagram of the configuration of a conventional optical disk device. In FIG. 6 , an optical head 100 is made up of a light source 101 , a collimator lens 102 , a polarizing beam splitter 103 , a quarter wavelength plate 104 , an objective lens 105 , a converging lens 107 , a detector 108 , and a tracking actuator 123 .
[0012] The light source 101 is a semiconductor laser device, which outputs an optical beam onto the information side of the optical disk 506 . The collimator lens 102 converts the divergent light emitted from the light source 101 into parallel light. The polarizing beam splitter 103 is an optical device that reflects all of the linear polarized light emitted from the light source 101 , and transmits all of the linear polarized light perpendicular to the linear polarized light emitted from the light source 101 . The quarter wavelength plate 104 is an optical device that converts the transmitted polarized light from circular polarized light to linear polarized light, or from linear polarized light into circular polarized light. The objective lens 105 converges the optical beam onto the information side of the optical disk 506 . The converging lens 107 converges the optical beam transmitted by the polarizing beam splitter 103 on the detector 108 . The detector 108 is a device that converts the light it receives into an electrical signal, and is split up into four detection regions. The tracking actuator 123 is a member that moves the focal point of the optical beam in the radial direction of the optical disk 506 .
[0013] FIG. 7 is a plan view of the detector 108 . As shown in FIG. 7 , the detector 108 has four detection sub-regions A, B, C, and D. The left-right direction in the drawing is the radial direction of the optical disk 506 (hereinafter referred to as the tracking direction), while the vertical direction is the track lengthwise direction.
[0014] Preamps 109 a to 109 d are electrical devices that convert the output current of the four detection sub-regions A to D of the detector 108 into voltage. Adders 110 a to 110 d are electrical circuits that add two of the outputs of the preamps 109 a to 109 d and output the result. A subtracter 111 is an electrical circuit that subtracts the two output signals of the adders 110 c and 110 d and outputs the result. Comparators 112 a and 112 b are electrical circuits that digitize the outputs of the adders 110 a and 110 b . A phase comparator 113 compares the digitized signal outputted from the comparators 112 a and 112 b and outputs pulses with a time width corresponding to the phase advance or phase delay of the edge. A low pass filter 114 is an electrical circuit that smoothes the pulse signals outputted from the phase comparator 113 . A switch 115 is an electrical circuit that outputs either the output signal from the low pass filter 114 or the output signal from the subtracter 111 according to a command signal from a microcomputer 119 . A tracking controller 116 is a circuit that outputs a tracking control signal on the basis of the output signal from the switch 115 . An A/D converter 117 is a circuit that samples the tracking control signal from the tracking controller 116 and converts it into a discrete signal. A disturbance generator 118 is a circuit that outputs a disturbance signal of a specific frequency according to a command from the microcomputer 119 . An adder 120 is an electrical circuit that adds the tracking control signal from the tracking controller 116 and the disturbance signal from the disturbance generator 118 and outputs the result. A gain adjuster 121 is an electrical circuit that can set the gain to the desired value on the basis of a command signal from the microcomputer 119 . A tracking driver 122 is a circuit that outputs a tracking actuator drive signal on the basis of the signal outputted from the gain adjuster 121 . The tracking actuator 123 is an element that moves the objective lens 105 in the radial direction of the optical disk 506 . An adder 124 is an electrical circuit that adds the two output signals of the adders 110 c and 110 d and outputs the result. An address regenerator 125 is a circuit that reads and outputs an address from the total amount of light obtained at the detector 108 . A comparator 126 is an electrical circuit that digitizes and outputs the output signal from the switch 115 . A pulse counter 127 is a circuit that counts the number of rising edges of the digitized signal outputted from the comparator 126 . A memory 128 is a storage circuit for holding data. A transport motor driver 129 is a circuit that amplifies and outputs a transport motor drive signal outputted from the microcomputer 119 . A transport motor 130 is an element that moves the optical head 100 in the radial direction of the optical disk 506 .
[0015] The operation of a conventional optical disk device configured as above will be described through reference to FIG. 6 .
[0016] The optical beam of linear polarized light emitted from the light source 101 is incident on the collimator lens 102 and converted into parallel light by the collimator lens 102 . The optical beam that has been made into parallel light by the collimator lens 102 is incident on the polarizing beam splitter 103 . The optical beam reflected by the polarizing beam splitter 103 is converted into circular polarized light by the quarter wavelength plate 104 . The optical beam converted into circular polarized light by the quarter wavelength plate 104 is incident on the objective lens 105 , and is focused on the optical disk 506 . The optical beam reflected by the optical disk 506 is transmitted through the polarizing beam splitter 103 and is incident on the converging lens 107 . The optical beam that was incident on the converging lens 107 is then incident on the four sub-regions A to D of the detector 108 . The optical beam incident on the four sub-regions A to D of the detector 108 is converted into electrical signals for each region. The electrical signals converted for each region of the detector 108 are converted into voltage by the preamps 109 a to 109 d.
[0017] The tracking control operation in the RAM region will now be described.
[0018] The output signals from the preamps 109 a and 109 b are added by the adder 110 c . The output signals from the preamps 109 c and 109 d are added by the adder 110 d . The output signals from the adders 110 c and 110 d are subtracted by the subtracter 111 , which gives a tracking error signal (hereinafter referred to as TE signal) indicating the positional relation between a track and the light spot on the optical disk 506 .
[0019] The above method for detecting TE signals is generally called a push-pull method. If the optical beam deviates from the group track center, or from the land track center, the intensity distribution to the left and right of primary diffracted light diffracted at the edge of the track changes according to this offset. With a push-pull method, track offset is detected by utilizing this change in the intensity distribution. A TE signal obtained by push-pull method is called a push-pull TE signal (hereinafter referred to as a PPTE signal).
[0020] The PPTE signal that is the output signal from the subtracter 111 is inputted through the switch 115 to the tracking controller 116 , is transmitted through a low frequency compensation circuit, a phase compensation circuit, or other such circuit made up of a digital filter involving a digital signal processor (hereinafter referred to as a DSP), and becomes a tracking drive signal. The tracking drive signal outputted from the tracking controller 116 goes through the adder 120 and amplified to a specific gain in the gain adjuster 121 . The output signal from the gain adjuster 121 is inputted to and amplified by the tracking driver 122 , and outputted to the tracking actuator 123 .
[0021] The position of the objective lens 105 is controlled in the radial direction of the optical disk 506 by the above tracking control operation so that the optical beam focused on the optical disk 506 scans the desired track of the RAM region of the optical disk 506 .
[0022] Next, the tracking control operation in the ROM region will be described.
[0023] The output signals from the preamps 109 a and 109 c are added by the adder 110 a . The output signals from the preamps 109 b and 109 d are added by the adder 110 b . The output signals from the adders 110 a and 110 b are converted into digitized signals by the comparators 112 a and 112 b , respectively. The digitized signals from the comparators 112 a and 112 b are compared for phase by the phase comparator 113 , and pulses with a time width corresponding to the phase advance or phase delay of the edge are outputted. The pulse signals outputted from the phase comparator 113 are smoothed by the low pass filter 114 and become TE signals.
[0024] The above method for detecting TE signals is generally called a phase difference method. When the optical beam passes pits, the intensity distribution of the reflected light on the detector 108 varies with the position of the optical beam in the tracking direction, which produces a deviation in the phase of each of the diagonal sum signals of the four sub-regions. The phase difference method involves detecting track offset by utilizing this deviation in phase. A TE signal obtained by phase difference method will hereinafter be referred to as a phase difference TE signal.
[0025] The phase difference TE signal that is the output signal from the low pass filter 114 is inputted through the switch 115 to the tracking controller 116 . The processing after this is the same as that in the tracking operation performed in the RAM region.
[0026] The position of the objective lens 105 is controlled in the radial direction of the optical disk 506 by the above tracking control operation so that the optical beam focused on the optical disk 506 scans the desired track of the ROM region of the optical disk 506 .
[0027] The “search operation” will also be described through reference to FIG. 6 . This search operation is an operation in which the optical beam is moved from a state of being located on a track in the RAM region to a state of being located on the desired track in the ROM region, or, conversely, an operation in which the optical beam is moved from the ROM region to the RAM region.
[0028] Before describing this “search operation,” the “address regeneration operation” will be described first. Address regeneration is an operation in which the current address of the light spot is obtained.
[0029] The output signals from the adders 10 c and 110 d are added by the adder 124 , producing a signal corresponding to the total amount of light obtained at the detector 108 . The output signal from the adder 124 (the total amount of light) is inputted to the address regenerator 125 . The address regenerator 125 digitizes the input signal so as to read the address, and the read address is outputted to the microcomputer 119 . The above address regeneration operation allows the optical disk device to obtain the current address of the light spot.
[0030] Next, the search operation from the RAM region to the ROM region will be described.
[0031] A boundary address ADb between the ROM region and the RAM region is stored in a memory 128 . When the address ADt of the desired track is inputted to the microcomputer 119 , the microcomputer 119 obtains the current address AD 0 from the address regenerator 125 and calculates the number of tracks Nt (=AD 0 −ADt) between the current track and the desired track. The microcomputer 119 also compares the boundary address ADb with the desired track address ADt to find whether the desired track is in the ROM region, and calculates the number of tracks Nb (=AD 0 −ADb) until the ROM region is entered. The microcomputer 119 also produces a transport motor drive signal on the basis of the calculated number of tracks Nt, and outputs this signal to the transport motor driver 129 . The transport motor driver 129 amplifies the transport motor drive signal and outputs it to the transport motor 130 .
[0032] A PPTE signal is generated when the optical head 100 is moved by the transport motor 130 in the radial direction of the optical disk 506 . This PPTE signal is inputted through the switch 115 to the comparator 126 , where it is digitized. The pulse counter 127 counts the number of rising edges of the digitized signal from the comparator 126 , so that the number of tracks Nc crossed by the optical beam since the start of the search operation is outputted to the microcomputer 119 . The microcomputer 119 reads the number of tracks Nc crossed by the optical beam since the start of the search operation, and compares this number to see if Nc is greater or less than the number of tracks Nb until the ROM region is entered. If Nc is less than Nb, the microcomputer 119 leaves the output signal from the switch 115 as a PPTE signal. If Nc is greater than or equal to Nb, the microcomputer 119 switches the output signal from the switch 115 from a PPTE signal to a phase difference TE signal. Further, when the microcomputer 119 reads the number of tracks Nc crossed by the optical beam since the start of the search operation, if Nc is equal to Nt, the count of the pulse counter 127 is reset and tracking control is performed. The tracking control operation here is performed on the basis of the phase difference TE signal. After this, the microcomputer 119 obtains the current address from the address regenerator 125 , and if the obtained address matches the desired address, the track search operation is concluded, but if there is no match, the above track search operation is repeated until the desired track is found.
[0033] The search operation from the ROM region to the RAM region is the same. Specifically, the microcomputer 119 compares the number of tracks Nb (=ADb−AD 0 ) until the RAM region is entered to see if it is greater or less than the number of tracks Nc crossed by the optical beam since the start of the search operation. If Nc is less than Nb, the microcomputer 119 leaves the output signal from the switch 115 as a phase difference TE signal. If Nc is greater than or equal to Nb, the microcomputer 119 switches the output signal from the switch 115 from a phase difference TE signal to a PPTE signal. After this, if Nc and Nt are equal, the microcomputer 119 resets the count of the pulse counter 127 , and performs tracking control. The tracking control operation here is performed on the basis of the PPTE signal.
[0034] As discussed above, with a conventional optical disk device, if the light spot is moved over the RAM region, a TE signal is produced by a PPTE signal detection method, and if the light spot is moving over the ROM region, a TE signal is produced by a phase difference TE signal detection method.
[0035] Further, this optical disk device is configured such that tracking control is performed by suitably switching the TE signal detection method according to the movement between the RAM region and the ROM region.
[0036] Another type of optical disk device is one that automatically adjusts the loop gain of tracking control in each region in order to ensure the control characteristics needed for the tracking control system (see, for example, Japanese Laid-Open Patent Application H4-19830 (pages 2 to 5, FIGS. 1 to 7)).
[0037] The adjustment of the loop gain in a tracking control system will now be described through reference to FIG. 6 .
[0038] The microcomputer 119 generates a disturbance signal of a specific frequency by means of the built-in disturbance generator 118 . This disturbance signal is applied to the tracking control system by the adder 120 . Along with the generation and application of the disturbance signal, the microcomputer 119 also samples and takes in the response signal of the tracking control system with respect to this disturbance signal by means of the A/D converter 117 . Further, the microcomputer 119 calculates the disturbance signal applied to the tracking control system and the response signal that is taken in, and measures the ratio between the applied disturbance signal and the incorporated response signal (hereinafter referred to as the loop gain), or the phase difference between the applied disturbance signal and the incorporated response signal (hereinafter referred to as the phase difference). After this, the microcomputer 119 actuates the gain adjuster 121 according to the measured loop gain or phase difference, so that the tracking control system is adjusted to a specific loop gain.
[0039] This loop gain adjustment operation results in the optimal loop gain for the tracking control system, allowing stable tracking control to be achieved.
[0040] As discussed above, this conventional optical disk device is configured such that loop gain adjustment results in the optimal loop gain for the tracking control system, allowing stable tracking control to be achieved. However, when the RAM region, which is composed of land and groove tracks, and the ROM region, which is composed of pit strings, are mixed together in a disk, as is the case with the optical disk 506 , it is necessary to switch between two different detection methods for tracking control, which leads to a larger dedicated circuit in the optical disk device.
[0041] Furthermore, the loop gain adjustment has to be performed for the RAM region and for the ROM region in order to achieve stable tracking control in each region, so adjustment takes longer, which leads to lower performance of the optical disk device.
[0042] With the next-generation high-density optical disks that allow both recording and reproduction, the recording of information ahead of time in the ROM region is accomplished not by pit strings, but by minutely varying (wobbling) the track shape in the radial direction of the optical disk. In addition, the RAM region is formed by continuous, convex and concave guide grooves, just as with conventional configurations.
[0043] Employing the above configuration for these next-generation high-density optical disks allows the same TE signal detection method, namely, PPTE detection, to be used in both the ROM region and the RAM region.
[0044] When the recording of information in the ROM region of an optical disk is accomplished by the above-mentioned wobbling, the track pitch must be wider in the ROM region than in the RAM region in order to wobble the track. In other words, the optical disk has a structure in which the track pitch is different in the RAM region and the ROM region.
[0045] The following problems are encountered when a PPTE signal detection method is applied to an optical disk such as this that has a plurality of regions of different track pitch.
[0046] FIG. 8 is a diagram of the correspondence between the PPTE signal waveform and the tracks on an optical disk 106 having regions of different track pitch. FIG. 8 a is a cross section of the optical disk 106 in its radial direction. As shown in the drawing, region 1 is a region with a track pitch of Tp 1 , while region 2 is a region of Tp 2 . FIG. 8 b is a waveform diagram obtained by plotting the PPTE signal obtained at various locations along the horizontal axis in FIG. 8 a.
[0047] As shown in FIG. 8 , the amplitude of the TE signal obtained by PPTE signal detection is dependent on the track pitch where the light spot is located. Accordingly, the detection sensitivity for the TE signal is different in regions 1 and 2, which have different track pitches. Specifically, even if the tracking control loop gain in region 1 is optimally adjusted by loop gain adjustment, the loop gain will still not be optimal in region 2. Therefore, a problem is that stable tracking control cannot be ensured in region 2 even when using an adjusted loop gain in region 1.
[0048] It is also possible to perform the adjustment of tracking control loop gain for each region in order to avoid this problem. In this case, the stability of tracking control can be ensured for all regions, but loop gain adjustment has to be carried out once for every region. Consequently, just as with a conventional optical disk device, this leads to longer adjustment time and lower performance of the optical disk device.
[0049] The present invention was conceived in an effort to solve the above problems, and provides an optical disk device that includes tracking control means for estimating the loop gain so that the desired tracking control characteristics will be obtained in all of the regions of an optical disk having a plurality of regions of different track pitch.
SUMMARY OF THE INVENTION
[0050] The present invention provides an optical disk device for recording information in first and second regions of an information carrier having two or more regions of different track pitch, or for reproducing information that has been recorded, said optical disk device comprising focusing means, movement means, light receiving means, track offset detection means, tracking control means, loop gain adjustment means, and loop gain estimation means. The focusing means focuses the optical beam and directs it at the information carrier. The movement means moves the focal point of the optical beam focused by the focusing means in the radial direction of the information carrier. The light receiving means receives the optical beam reflected by the information side of the information carrier. The track offset detection means detects offset between the track and the focal point of the optical beam on the basis of a signal from the light receiving means. The tracking control means drives the movement means on the basis of a signal from the track offset detection means, and controls the focal point of the optical beam so as to scan the track. The loop gain adjustment means adjusts a first loop gain used in tracking control of the first region, which is the loop gain of the tracking control means. The loop gain estimation means estimates a second loop gain used in tracking control of the second region on the basis of the first loop gain of the first region determined by the loop gain adjustment means.
[0051] The “radial direction of the information carrier” is the direction perpendicular to the track, for example. The light receiving means is, for example, a means for receiving return light of the optical beam reflected on the information side, in a plurality of sub-regions. “Tracking control” means controlling the focal point of the optical beam so that it accurately scans the track. The loop gain estimation means estimates the second loop gain before the focal point of the optical beam moves from the first region to the second region.
[0052] With the optical disk device of the present invention it is possible to set the optimal tracking control loop gain in both region 1 and region 2. Also, because stability of the tracking control is ensured in both region 1 and region 2, in which the track pitch is different, reliability of reproduction and recording is improved.
[0053] With the optical disk device of the present invention, the loop gain estimation means estimates the second loop gain of the second region on the basis of the first loop gain of the first region and the ratio between the amplitude of the signal from the track offset detection means in the first region and the amplitude of the signal from the track offset detection means in the second region.
[0054] With the optical disk device of the present invention, because there is no need to perform loop gain adjustment in the second region, adjustment takes less time during device start-up, which improves the performance of the device.
[0055] With the optical disk device of the present invention, the loop gain estimation means has storage means for storing the ratio between the track pitch in the first region and the track pitch in the second region as a predetermined value, and estimates the second loop gain of the second region on the basis of the first loop gain of the first region and the predetermined value stored in the storage means.
[0056] Because the loop gain does not have to be adjusted for each region with the optical disk device of the present invention, adjustment takes less time during device start-up, which improves the performance of the device.
[0057] The optical disk device of the present invention further comprises region determination means for determining whether the focal point of the optical beam is located in the first region or the second region, wherein the loop gain of the tracking control means is switched according to the determination result of the region determination means.
[0058] With the optical disk device of the present invention, optimal tracking control is possible in both regions, which improves the reliability of reproduction and recording.
[0059] With the optical disk device of the present invention, the region determination means determines the region in which the focal point of the optical beam is located from the change in amplitude of the signal detected by the track offset detection means.
[0060] The optical disk device of the present invention makes it possible to switch the tracking control loop gain according to the current location of the focal point of the optical beam, affording optimal tracking control regardless of the region and improving the reliability of reproduction and recording.
[0061] The optical disk device of the present invention further comprises track search means for moving the focal point of the optical beam to a desired track, wherein the region determination means determines the region in which the focal point of the optical beam is located when the focal point of the optical beam is moved across the track by the track search means.
[0062] With the optical disk device of the present invention, when there is movement between regions due to a track search operation, it is possible to set the optimal tracking control loop gain regardless of the region. Accordingly, it is possible to ensure good tracking control performance after a track search operation straddling a region, which improves the reliability of reproduction and recording.
[0063] With the optical disk device of the present invention, the first region on the information carrier is a region in which predetermined information has been recorded using a change in the shape of the track, and the predetermined information is reproduced before the focal point of the optical beam moves to the second region.
[0064] With the optical disk device of the present invention, the loop gain does not have to be adjusted in the second region, which means that adjustment takes less time during the start-up of the device, and this improves the performance of the device.
[0065] With the optical disk device of the present invention, the second region on the information carrier is a region in which the recording or reproduction of information is performed.
[0066] With the optical disk device of the present invention, a recording or reproduction operation can be commenced without first adjusting the loop gain in the second region. This improves the performance of the device.
[0067] The loop gain setting method of the present invention is a method for setting the loop gain used in the tracking control of regions in an optical disk device that records information to first and second regions of an information carrier having two or more regions, or reproduces recorded information, comprising a loop gain adjustment step and a loop gain estimation step. In the loop gain adjustment step, a first loop gain used in tracking control of the first region is adjusted. In the loop gain estimation step, a second loop gain used in tracking control of the second region is estimated on the basis of the first loop gain of the first region determined in the loop gain adjustment step.
[0068] The loop gain setting method of the present invention makes it possible to set the optimal tracking control loop gain in both region 1 and region 2. A side benefit is that this ensures stability of tracking control in both region 1 and region 2, which have different track pitches, and this improves the reliability of reproduction and recording.
[0069] The loop gain setting program of the present invention is a program for executing on a computer a loop gain setting method for setting the loop gain used in the tracking control of regions in an optical disk device that records information to first and second regions of an information carrier having two or more regions, or reproduces recorded information. The loop gain setting method comprises a loop gain adjustment step and a loop gain estimation step. In the loop gain adjustment step, a first loop gain used in tracking control of the first region is adjusted. In the loop gain estimation step, a second loop gain used in tracking control of the second region is estimated on the basis of the first loop gain of the first region determined in the loop gain adjustment step.
[0070] The loop gain setting program of the present invention makes it possible to set the optimal tracking control loop gain in both region 1 and region 2. A side benefit is that this ensures stability of tracking control in both region 1 and region 2, which have different track pitches, and this improves the reliability of reproduction and recording.
[0071] Using the tracking control means of the present optical disk device increases tracking control stability and improves reliability in the reproduction and recording operations of the optical disk device.
[0072] These and other objects, features, aspects and advantages of the present invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses a preferred embodiment of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0073] Referring now to the attached drawings which form a part of this original disclosure:
[0074] FIG. 1 is a block diagram of an optical disk device according to one embodiment of the present invention;
[0075] FIG. 2 is a schematic of the structure of an optical disk having regions of different track pitch;
[0076] FIG. 3 is a waveform diagram of the correspondence between the PPTE signal amplitude level, the PPTE signal waveform, and the tracks on an optical disk having regions of different track pitch;
[0077] FIG. 4 is a block diagram of the configuration of an optical disk device that performs track jumping;
[0078] FIG. 5 is a schematic of the structure of a DVD-RAM;
[0079] FIG. 6 is a block diagram of a prior art optical disk device;
[0080] FIG. 7 is a plan view of the detection region of a detector 108 in a prior art optical disk device; and
[0081] FIG. 8 is a waveform diagram of the correspondence between the PPTE signal waveform and the tracks on an optical disk 106 having regions of different track pitch in a prior art optical disk device.
DETAILED DESCRIPTION
[0082] Embodiments of the present invention will now be described through reference to the drawings.
Embodiment 1
[0000] Configuration
[0083] FIG. 1 is a block diagram of the configuration of an optical disk device 200 in Embodiment 1. Those components that are the same as in a conventional optical disk device are numbered the same, and will not be described again. In FIG. 1 , the optical disk 106 has a plurality of regions of different track pitch.
[0084] FIG. 2 is a schematic of the structure of the optical disk 106 . FIG. 2 a is an overall view of the optical disk 106 .
[0085] The optical disk 106 is made up of two different doughnut-shaped regions (regions 1 and 2) separated in the radial direction of the disk. Each of these regions has a plurality of tracks. The track pitch (Tp 1 ) of region 1 here is 0.35 μm, while the track pitch (Tp 2 ) of region 2 is 0.32 μm.
[0086] Region 1 is a region in which information has been pre-recorded by wobbling the shape of the tracks. The recorded information is information that is necessary in the reproduction and recording of an installed optical disk, and can be the capacity of the optical disk, the number of information sides, or the laser emission pattern recommended for recording, for example.
[0087] Meanwhile, region 2 is a region having a recording material film and in which information can be optically recorded or reproduced. In FIG. 1 , an amplitude detector 131 is a circuit for detecting the signal amplitude of a PPTE signal.
[0088] As shown in FIG. 1 , the optical disk device comprises focusing means (optical head 100 ), movement means (tracking actuator 123 ), light receiving means (detector 108 ), track offset detection means, tracking control means, loop gain adjustment means, loop gain estimation means, region determination means, and search means.
[0089] The “track offset detection means” comprises the preamps 109 c and 109 d , the adders 110 c and 110 d , and the subtracter 111 .
[0090] The “tracking control means” mainly comprises the tracking controller 116 , the adder 120 , the gain adjuster 121 , and the tracking driver 122 .
[0091] The “loop gain adjustment means” comprises the A/D converter 117 , the microcomputer 119 , the disturbance generator 118 , the adder 120 , and the gain adjuster 121 .
[0092] The “loop gain estimation means” comprises the amplitude detector 131 , the microcomputer 119 , and storage means (memory 128 ).
[0093] The “region determination means” comprises the amplitude detector 131 and the microcomputer 119 .
[0094] The “search means” comprises the address regenerator 125 , the comparator 126 , the pulse counter 127 , the microcomputer 119 , the transport motor driver 129 , and the transport motor 130 .
[0000] Loop Gain Estimation
[0095] The loop gain estimation operation of the optical disk device 200 configured as above will now be described.
[0096] FIG. 3 is a diagram of the correspondence between the PPTE signal waveform and the tracks on an optical disk 106 having regions 1 and 2 of different track pitch. FIGS. 3 a and 3 b are the same as FIGS. 8 a and 8 b , and will therefore not be described again.
[0097] FIG. 3 c is a waveform diagram showing the result when the amplitude of the PPTE signal of FIG. 3 b was detected with the amplitude detector 131 . As shown in FIGS. 3 a to 3 c , the amplitudes of PPTE signals obtained by the amplitude detector 131 in region 1 and region 2 are termed A 1 and A 2 , respectively.
[0098] Since the tracking control loop gain is proportional to the PPTE signal amplitude, if G 1 and G 2 are the tracking control loop gain in region 1 and region 2, the relation of the following Formula 1 exists between G 1 and G 2 and A 1 and A 2 .
G 1 / G 2 = A 1 / A 2 (Formula 1)
[0099] It is assumed here that the gain of the gain adjuster 121 is set so that the loop gain adjustment will produce the optimal loop gain in region 1, and this gain setting be K 1 . In order to suitably set the tracking control loop gain in region 2 here, the gain K 2 at the gain adjuster 121 may be found from the following Formula 2, while taking into account Formula 1.
K 2 = K 1 × A 1 / A 2 (Formula 2)
[0100] The operation for finding the value of the gain K 2 from this formula will now be described.
[0101] The microcomputer 119 finds the amplitudes A 1 and A 2 of the PPTE signals in the two regions obtained by the amplitude detector 131 , by using peak detection, envelope detection, or another such method. The microcomputer 119 also uses the amplitude values and the gain setting K 1 , which is the result of loop gain adjustment in region 1, to solve Formula 2 and find the gain setting K 2 in region 2.
[0102] The above configuration makes it possible to estimate the optimal loop gain in region 2 on the basis of the ratio A 1 /A 2 of the PPTE signal amplitudes in regions 1 and 2, and the loop gain adjustment result K 1 in region 1. Specifically, the optimal loop gain can be set in both region 1 and region 2.
[0103] With this embodiment, the PPTE signal amplitude in each region is detected, and the ratio of the two amplitudes is used to estimate the loop gain. However, since the PPTE signal amplitude is proportional to the track pitch, this estimation can also be performed using track pitch. Specifically, the ratio Tp 1 /Tp 2 of the track pitches Tp 1 and Tp 2 is stored ahead of time in the memory 128 , and the microcomputer 119 estimates the loop gain in region 2 by using the loop gain adjustment result for region 1 and the track pitch ratio stored in the memory 128 . The effect is the same with this method. That is, the loop gain in region 2 can be estimated without using the amplitude detection result produced by the amplitude detector 131 .
[0104] If the loop gain is adjusted in region 1, this loop gain estimation method does not require that the same adjustment be performed in another region. Specifically, the optimal loop gain can be estimated for each region merely by adjusting the loop gain in region 1 and measuring the PPTE signal amplitudes. Accordingly, the loop gain estimation method of the present invention leads to a reduction in loop gain adjustment time in the regions, which helps improve the performance of the optical disk device.
[0105] Switching of Loop Gain
[0106] Next, the operation of the optical disk device 200 in this embodiment will be described for a case in which the loop gain is switched between region 1 and region 2. This embodiment is characterized in that region determination is performed by using the PPTE signal amplitudes during the search operation, and the loop gain is switched for each region.
[0107] The following description is through reference to FIGS. 1 and 3 .
[0108] Just as with a conventional optical disk device, when the address ADt of the desired track is inputted to the microcomputer 119 , the microcomputer 119 obtains the current address AD 0 from the address regenerator 125 and calculates the number of tracks Nt (=AD 0 −ADt) between the current track and the desired track. The microcomputer 119 also resets the count of the pulse counter 127 and disables tracking control. Further, the microcomputer 119 produces a transport motor drive signal on the basis of the number of tracks Nt, and outputs the transport motor drive signal thus produced to the transport motor driver 129 . The transport motor 130 is driven according to the transport motor drive signal, and when the optical head 100 moves in the radial direction of the optical disk 506 , a PPTE signal is generated.
[0109] As shown in FIGS. 3 a to 3 c , the PPTE signals obtained from regions of different track pitch have different amplitudes. Therefore, as shown in FIG. 3 c , the region in which the light spot is located can be determined by examining the change in amplitude of the PPTE signal detected by the amplitude detector 131 during the search operation.
[0110] More specifically, the amplitude A 0 of the PPTE signal obtained from the amplitude detector 131 during the search operation is compared to see if it is greater or less than a specific level A 3 . If A 0 is greater than A 3 (such as when A 0 is A 1 ), the microcomputer 119 determines that the light spot is in region 1. The microcomputer 119 therefore sets the gain setting of the gain adjuster 121 to K 1 , which is the loop gain adjustment result for region 1. If A 0 is less than A 3 (such as when A 0 is A 2 ), the microcomputer 119 determines that the light spot is in region 2. The microcomputer 119 therefore sets the gain setting of the gain adjuster 121 to K 2 , which is the estimation result produced by the above loop gain estimation operation.
[0111] The microcomputer 119 also reads the number of tracks Nc cross by the optical beam since the start of the search operation, and if Nc is equal to Nt, the microcomputer 119 resets the count of the pulse counter 127 and enables tracking control. After this, the microcomputer 119 obtains the current address from the address regenerator 125 , and if the obtained address matches the desired address, the track search operation is concluded, but if there is no match, the above track search operation is repeated until the desired track is found.
[0112] Employing the above configuration makes it possible to determine whether the current light spot is located in region 1 or region 2 by using the PPTE signal amplitude during the track search operation, and to switch the gain setting of the gain adjuster 121 between K 1 (the setting of region 1) and K 2 (the setting of region 2) according to the above determination result.
[0113] Therefore, even when there is movement between regions of different track pitch due to the track search operation, the optimal tracking control loop gain can be set in both regions. Accordingly, it is possible to ensure good tracking control performance (track following performance) after a track search operation straddling a region, which improves the performance of the optical disk device.
[0114] As discussed above, with an optical disk having a plurality of regions of different track pitch, the PPTE signal amplitude in each region varies with the track pitch. Accordingly, with prior art, the tracking control loop gain could not be optimized for all regions unless the loop gain was adjusted for every region.
[0115] With the optical disk device 200 in this embodiment, however, it is possible to estimate the optimal loop gain for each region by using the loop gain adjustment result for one region and the PPTE signal amplitude ratio for the regions. Therefore, there is no need to perform loop gain adjustment for every region, so adjustment takes less time during start-up.
[0116] Also, with the optical disk device 200 of this embodiment, it is possible to determine a region from the change in the PPTE signal amplitude during the track search operation.
[0117] Furthermore, it is possible to set the optimal tracking control loop gain for each region by combining the estimation of loop gain with the determination of region, and switching the estimated loop gain according to the determination result.
[0118] Therefore, when this embodiment is employed, stable tracking control can be achieved for each region of an optical disk having a plurality of regions of different track pitch. Accordingly, an optical disk device with high reliability can be realized as a device for reproduction and recording of an optical disk.
[0119] At the same time, the performance of the optical disk device is improved because adjustment takes less time during start-up.
[0000] Track Jumping
[0120] With the optical disk device of this embodiment, the region is determined from the change in the PPTE signal amplitude during a track search operation. This involves detecting the track pitch of a region from the PPTE signal amplitude. This track pitch detection result can be utilized for a track search operation, which will be described below.
[0121] In a track search operation, an operation called track jumping is also performed in addition to the above-mentioned operation of moving the optical head 100 in the radial direction with the transport motor 130 . This track jumping operation will be described through reference to FIG. 4 .
[0122] FIG. 4 is a block diagram of the configuration of an optical disk device 200 ′ that performs track jumping. A jump pulse generator 132 outputs a pulsed drive signal (hereinafter referred to as track jump signal) to an adder 133 according to a command from the microcomputer 119 . The adder 133 adds the output signal from the gain adjuster 121 and the track jump signal and outputs the result to the tracking driver 122 . The output signal from the adder 133 is inputted to the tracking driver 122 and amplified, then outputted to the tracking actuator 123 . As a result of the above, the objective lens 105 is moved by one track in the radial direction. This operation is called track jumping.
[0123] The optimal wave height of the pulsed track jump signal used in this track jumping operation is a function of track pitch. In view of this, with the optical disk device in this embodiment, the wave height of the track jump signal is increased or decreased according to the track pitch detected for each region. Specifically, the greater the track pitch detected in the track search operation, the greater the wave height of the outputted track jump signal. As a result, track jumping can be performed stably and precisely. This also affords a more stable and reliable track search operation.
Other Embodiments
[0124] (1) The description in this embodiment assumed that the optical disk 106 had the same configuration as a BD (Blu-ray Disc). The present invention described in this embodiment, however, is not limited to a BD, and can also be applied to other optical disks.
[0125] (2) The effects of the present invention are particularly pronounced when the same method for detecting tracking error signals is used for a plurality of regions of different track pitch. For instance, with a DVD-RAM, a ROM region having pit strings is formed around the inner periphery, while a RAM region having a continuous groove is formed around the outer periphery. With a conventional method, a different method for detecting a tracking error signal was applied for each region, with a phase difference method being applied for the ROM region, and a push-pull method for the RAM region. Furthermore, with a conventional method, the track pitch is different in each region, with the track pitch in the ROM region being 0.8 μm, and the track pitch in the RAM region 1.6 μm.
[0126] With a DVD-RAM such as this, because the regions have different track pitches, and different methods for detecting a tracking error signal are used for the various regions, the suitable tracking loop gain is different from each region.
[0127] Consequently, with prior art, when the tracking loop gain is found for each region of a DVD-RAM, the tracking loop gain is usually adjusted for each region, and it is not customary to estimate the tracking loop gain of one region on the basis of the tracking loop gain adjusted in another region. On the contrary, the proper tracking loop gain cannot be estimated even if an estimation of the tracking loop gain is attempted using tracking error signals obtained by different tracking error signal detection methods.
[0128] Meanwhile, with a BD, for example, a RAM region having a continuous groove in which information is recorded by wobbling the shape of the tracks is formed around the inner periphery, while a RAM region having a continuous groove is formed around the outer periphery. The same tracking error signal detection method (push-pull method) is used for both regions. The track pitch in each region is different, with the track pitch in the inner RAM region being 0.35 μm, and the track pitch in the outer RAM region 0.32 μm.
[0129] As discussed above, with a BD, only the track pitch in each region is different, meaning that the suitable tracking loop gain for each region is also different.
[0130] In view of this, when the present invention is applied to a BD, the tracking loop gain can be estimated by using tracking error signals obtained by the same tracking error signal detection method, so the proper tracking loop gain can be estimated.
[0131] (3) The effects of the present invention are particularly pronounced when the invention is used for an optical disk that requires relatively high tracking control precision. For instance, the present invention is particularly effective when used for a BD. More specifically, since the track pitch is narrower with a BD, tracking control needs to be more precise than with a DVD-RAM (relatively speaking, a DVD-RAM does not require that much precision). For example, the permissible error in tracking control is 0.022 μm with a DVD-RAM, whereas the permissible error is only 0.009 μm with a BD.
[0132] To perform high-precision tracking control, the tracking loop gain must be set properly in each of the regions with different track pitches. In the past, with a DVD-RAM, for instance, tracking control did not require that much precision. Because of this, variance between optical disks or drives did not affect tracking control very much. Even when the tracking loop gain is found for regions of different track pitch, if the difference in the tracking loop gain between the various regions is determined ahead of time, and the tracking loop gain for these regions is estimated from the tracking loop gain of one region and the predetermined difference, it will be possible to achieve tracking control of the minimum required precision.
[0133] On the other hand, a BD, for example, requires high-precision tracking control. Accordingly, any variance between optical disks or drives greatly affects tracking control, so the tracking loop gain must be properly adjusted for each region. In this case, the tracking loop gain may be adjusted for every single region, but this means that adjustment will take a long time, in addition to the problems discussed in (4) below.
[0134] In view of this, if the present invention is applied, so that the tracking loop gain is adjusted for one region, and the tracking loop gain is estimated for any other regions from the result of measuring the amplitude of tracking error signals, tracking control can be carried out at high precision, and the adjustment of the loop gain will not take as long.
[0135] (4) The effects of the present invention are particularly pronounced when applied to an optical disk that requires even higher tracking control precision. For instance, as discussed in (3) above, the tracking loop gain can be adjusted for every region in situations that require high-precision tracking control. In this case, if the tracking loop gain is adjusted in the RAM region around the outer periphery, the value of the adjusted tracking loop gain will be affected by whether or not information has been recorded in this RAM region. Accordingly, when high-precision tracking control is required, adjusting the tracking loop gain for every region is not suitable. In addition, adjusting the tracking loop gain for every region takes longer, so adjustment takes more time during start-up.
[0136] When the present invention is used, on the other hand, adjustment of the tracking loop gain is performed only in the RAM region around the inner periphery, where no information has been recorded. Furthermore, the value of the tracking loop gain in the RAM region around the outer periphery is estimated from the value of the adjusted tracking loop gain. Accordingly, in the present invention, adjustment takes less time, and adjusting the tracking loop gain for every region can be carried out.
[0137] (5) In this embodiment, the constituent elements that successively processed the output signals from the preamps 109 a to 109 d were all electrical circuits. Specifically, the above description was for the utilization of analog circuits. However, the effect will be the same if these constituent elements are digital circuits instead. Specifically, the output signals from the preamps 109 a to 109 d may be converted into digital signals by an A/D converter, and these digital signals may be successively processed by various constituent elements consisting of digital circuits.
[0138] (6) In this embodiment, the plurality of regions of different track pitch consisted of two regions (region 1 and region 2), but the number of regions is not limited to two.
[0139] (7) Also, in this embodiment, a method in which disturbance of a specific frequency was applied to the control system, the response waveform was sampled, calculations were performed, and adjustments were made so as to obtain a specific loop gain was employed as the loop gain adjustment means, but the loop gain adjustment means is not limited to this method.
[0140] (8) In the above embodiment, the various components shown in block diagrams may be formed by an integrated circuit configured integrally or separately. For instance, in FIGS. 1 and 4 , the components other than the optical disk 106 , the optical head 100 , and the transport motor 130 can be formed by integrated circuits. Also, the functions of components that can be formed by integrated circuits may be executed by programs on a computer or the like.
[0141] The optical disk device of the present invention allows stable tracking control in all regions of an optical disk having a plurality of regions of different track pitch, and is useful as a method for increasing the reliability of devices that reproduce and record from and to an optical disk.
[0142] Further, a disk format is conceivable in which the track pitch of a specific region on the inner periphery is widened to stabilize a servo, and system information or disk information is entered ahead of time in this region, and the present invention is useful with such disks as well.
[0143] Also, the optical disk device of the present invention shortens the time adjustment takes during start-up, and is useful as a method for improving the performance of devices that reproduce and record from and to an optical disk.
[0144] This application claims priority to Japanese Patent Application No. 2004-126592. The entire disclosure of Japanese Patent Application No. 2004-126592 is hereby incorporated herein by reference.
[0145] While only selected embodiments have been chosen to illustrate the present invention, it will be apparent to those skilled in the art from this disclosure that various changes and modifications can be made herein without departing from the scope of the invention as defined in the appended claims. Furthermore, the foregoing description of the embodiments according to the present invention are provided for illustration only, and not for the purpose of limiting the invention as defined by the appended claims and their equivalents. | An optical disk device is disclosed that includes loop gain adjustment means for finding the first tracking loop gain of a first region, and loop gain estimation means for estimating the second loop gain of a second region on the basis of the loop gain of the first region. Accordingly, it is possible to set the optimal tracking control loop gain for all regions. As a side benefit, good tracking control stability can be ensured regardless of the region, which improves the reliability of reproduction and recording. | 6 |
FIELD OF INVENTION
[0001] The present invention broadly relates to a pharmaceutical kit and method of packaging the kit for treating migraine headaches.
BACKGROUND
[0002] Migraine is an age old disease which has been described and dealt with in various ways throughout history by many cultures and civilization. For example, old English literature described migraine as “Hemicrania”, implying that migraine headache is unilateral in the head. However migraine does not always attack in a unilateral manner. It took several centuries to understand the scientific basis and recognize the wide clinical spectrum of this very common illness.
[0003] As of recent times, in the United States alone, there are 28 million people suffering from migraine. Of that population, approximately 21 million are female and 7 million are male. One in four households has at least one migraine sufferer. Migraine prevalence peaks in the 25 to 55 year age ranges in both genders. In the 1999 HIS (International Headache Society) estimate, 52% of the total population of migraine cases remain undiagnosed. The undiagnosed sufferers are most likely self-medicating with over the counter medications. “Migraine Awareness”, i.e., public knowledge of migraine illness, is much more prevalent in the urban areas than in the interior heartland of the United States, for example.
[0004] Additionally, migraine is the number one cause of lost work days. Migraine sufferers visit emergency rooms and doctor's offices more frequently than non-migraine patients. The total cost of lost work in the United States alone is approximately in the range of 5.6 to 17.2 billion dollars a year. Attendant health care costs rival these figures.
[0005] Despite tremendous economic pressures to develop a “magic bullet” style treatment useful in treating the full range of the illness, no manufacturer has done so. For example, a most popular migraine remedy, Sumatriptan, has been used to treat around 140 million cases. However this drug addresses just one aspect of the complex migraine illness. Subjects who are being treated with Sumatriptan most likely take other drugs, over the counter or prescription, to treat aspects of the disease that Sumatriptan does not address. There remains a need for a more convenient approach to complete migraine treatment wherein all of the components and medications necessary for migraine treatment are provided.
[0006] The pathogenesis of migraine may be summarized by:
[0007] (1) genetic pre-disposition (Almost 90% of migraine sufferers have a family history of the illness);
[0008] (2) Environmental factors such as food, atmospheric and climatic changes, emotional upheavals, physical stress, sleep deprivation, and social aggravations; and
[0009] (3) The “cascade phenomenon of migraine”, i.e., neuro-chemical changes occurring in the brain.
[0010] The most important chemical change in the brain in migraine is the decline in the level of the neurotransmitter serotonin. All modern treatment methods to treat migraine attacks use a generic group of drugs called Triptans. Triptans work by elevating the brain serotonin levels through action at the nerve junctions, i.e., synapses. This triggering event results in the release of a variety of other neuro-peptides and mono-amines around the blood vessels in the meninges, i.e., covering of the brain, and in the brain itself. Some of these important neuro-peptides are bradykinin, prostaglandin. A few of the important mono-amines are dopamine and norepinephrine. Their roles are described in further detail below.
[0011] Migraine is a complex illness in which not only serotonin, but other neuro-peptides are implicated. The acute aseptic, i.e., non-infectious, inflammatory reaction of the meninges which causes the severe headache is mediated through the release of a chemical, prostaglandin. Thus, the common anti-inflammatory drugs like Aspirin, Tylenol, Ibuprofen, Alleve etc. are effective in treating the severe headache in migraine attacks because these drugs antagonize prostaglandins.
[0012] During a migraine attack, there is a release of norepinephrin which accounts for the sense of anxiety, palpitation and high blood pressure in the migraine sufferer. Anxiety relieving drugs like Valium, Xanax and Paxil are often useful in treating migraine.
[0013] Release of another important chemical substance called dopamine explains the nausea and vomiting and the tremendous mood swings in migraine. Reglan (Chlorpropomide) is a dopamine blocking agent and hence is successfully used in the acute stages of migraine to treat accompanying symptoms other than the headache, such as nausea and mood swings.
[0014] The drug manufacturers typically put out one single product in the market and promote it studiously. There are four different Triptan preparations already being marketed and several more are expected soon. However, as mentioned above, a “single drug” approach using Triptan, for example, cannot treat migraine adequately.
[0015] A well experienced migraine doctor skillfully prescribes a combination of drugs to treat acute migraine. Under current state of the art, depending upon the presenting manifestation of a migraine attack, the migraine doctor may prescribe a Triptan, e.g., Imitrex, an anti-prostaglandin drug, e.g., Ibuprofen and an anti-dopamine drug, e.g., Reglan, . Patients, very often, use this “cocktail” approach on their own. Surprisingly, it is not at all uncommon to find doctors prescribing only single drug treatment for migraine, which leaves the patient only with partial relief of headache, leaving them unhappy and seeking other opinions. As described above, to successfully treat a migraine attack, there exists the need to use a combination of several drugs. Yet, no manufacturer has assembled a kit with such a combination.
SUMMARY OF THE INVENTION
[0016] This invention comprises a pharmaceutical kit for treating migraine headaches, and a method for preparing the pharmaceutical kit. The preparation is a manufacturing process which includes packaging in a container a plurality of specific compounds used in the treatment of migraine that are serotonin level elevating, prostaglandin inhibiting and dopamine blocking, preferably a therapeutically effective amount of each compound sufficient to treat at least 2 separate migraine headache attacks, and, providing use instructions for the effective administering of the compounds for migraine headache treatment. The invention further comprises useful features that provide advantages to the patient as well as the provider, i.e., doctor and pharmacy. For example, preferably separate packages for each compound are packed in separated compartments within the container.
[0017] Specifically, there is provided a method for preparing a migraine headache treatment which comprises: packaging in a container a therapeutically effective dosage of a serotonin level elevating pharmaceutical compound used in the treatment of migraine; packaging in the container a therapeutically effective dosage of a prostaglandin antagonizing, i.e. inhibiting, pharmaceutical compound used in the treatment of migraine; packaging in the container a therapeutically effective dosage of a dopamine blocking pharmaceutical compound used in the treatment of migraine; including and packaged with said container a vessel of water for use in administering the pharmaceutical compounds which are to be orally administered; and packaging in the container instructions for usage of all of the packaged compounds which are contained in the container.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The present invention will now be described in more detail by referring to the drawings that accompany the present application. It is noted that in the accompanying drawings like reference numerals are used for describing like and corresponding elements thereof.
[0019] [0019]FIG. 1 shows a preferred pharmaceutical kit including injection devices and pharmaceutical compounds of the present invention;
[0020] [0020]FIG. 2 shows a preferred container including a nasal spray device and alternative pharmaceutical compounds within the container;
[0021] [0021]FIG. 3 shows a preferred pharmaceutical kit including pharmaceutical compounds solely for oral administration;
[0022] [0022]FIG. 4 a shows a preferred implementation comprising a water bottle having coupling threads for attaching the pharmaceutical kit container;
[0023] [0023]FIG. 4 b shows a side cutaway view of a preferred container having the complete regimen of orally administered, individually packaged pharmaceutical compounds;
[0024] [0024]FIG. 4 c shows a top down plane view of the preferred container of FIG. 4 b;
[0025] [0025]FIG. 5 shows the water bottle coupled to the pharmaceutical kit container; and
[0026] [0026]FIG. 6 shows bottom of integrally manufactured water bottle and pharmaceutical kit container with access means.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0027] An aspect of this invention applies to the preparation of a kit for the treatment of migraine headaches. In a preferred embodiment of this invention predetermined quantities representing a therapeutically effective dosage of several compounds for treatment of a migraine headache are packaged along with additional components such as a vessel of water, alcohol swabs and instructions for use, in a container by a manufacturing process which, preferably, seals the container and its contents into a self-contained, unitary, migraine headache treatment kit. Known pharmaceutical compounds may be provided, however it should be understood that yet to be developed compounds may also be used as they become available.
[0028] Preferably, each drug, i.e., pharmaceutical compound, in the kit is packed separately, yet the separately packed drugs are contained in a single, easy to use container, such as the container shown in FIG. 1 100 . In a preferred aspect of this pharmaceutical kit for treating migraine headaches, precise instructions 140 for use of all the constituents are also provided. Additionally, it is preferable that a kit contain enough medications, i.e., pharmaceutical compounds, to treat at least two migraine attacks. As shown in FIG. 1, in a preferred implementation, the container is manufactured such that its compartments 130 , 160 , 165 fit neatly around the individually packaged predetermined number of pharmaceutical compounds 132 , injection administration devices 110 for drug injection below the skin of a user, and a vessel of water, e.g., water bottle 120 . Sufficient space is also provided for additional components such as alcohol swab packet 170 and instructions 140 . Additionally, the separately packed drugs, i.e., the individually packaged pharmaceutical compounds 132 preferably include labels on the separate packaging identifying the particular pharmaceutical compound contained in the package. Preferably, a container surface such as surface 105 includes a latching device 155 for keeping the contents secure within the container. Additionally, a preferred implementation of this invention includes a hand strap 150 for carrying the kit 100 . Although a container with basically rectilinear surfaces 105 , 145 is shown, the container may be provided in any shape and size which provides sufficient space for all of the kit components and pharmaceutical compounds, e.g., water bottle 120 , injection administration devices 110 , alcohol swab packet 170 , instructions 140 , pharmaceutical package 132 , and the like. The container may be made of a relatively soft material such as vinyl and foam, or may provide a relatively hard covering such as high impact plastic.
[0029] The container contents include a therapeutically effective dosage of pharmaceutical compounds used in the treatment of migraine, as well as other components to assist drug administration, such as alcohol swab packet 170 . Water bottle 120 is preferably a component that is provided in all implementations of this invention in order to facilitate administering oral dosage units of the pharmaceutical compounds, such as pills, capsules, tablets, and the like. The pharmaceutical compounds are chosen to address various aspects of the migraine condition, such as, e.g., headache, nausea and mood swings. In a preferred implementation of the current invention where all pharmaceutical compounds are oral dosage units, the container may be manufactured to contain more than one water bottle, as shown in FIG. 3 at 120 and 165 .
[0030] In another preferred implementation of this invention, the provided container is manufactured as a permanent attachment to a water bottle, such as container 410 attached to water bottle 415 so that container 410 and water bottle 415 form one integral manufactured drug kit 500 as shown in FIG. 5. The container 410 and water bottle 415 may be manufactured as an integrated, unitary member, with opening means, such as a sliding door, hinged door, or, as shown in FIG. 6, a revolving cover with hinge pin 610 and a cut out window 605 , over a bottom of container 410 , for providing access to the contents 132 of the pharmaceutical kit.
[0031] In another preferred implementation of this invention, it is understood that container 410 is, preferably, cylindrical, having an inner sidewall 409 , an outer sidewall 408 , and having a depth and size to permit the pharmaceutical compounds 132 and usage instructions 140 to fit inside the container 410 , and to permit the container 410 to securely attach, i.e., mate to e.g., the lower portion 417 of preferably cylindrical water bottle 415 by coupling lower portion 417 of water bottle 415 and container 410 together such that lower portion 417 and container 410 are securely held together by friction contact between them. Additionally, the coupling, in a preferred implementation, as shown in FIG. 4 b at 413 , may be provided by threads, preferably on inner sidewall 409 for threading the container 410 on to water bottle 415 . Water bottle 415 comprises complementary threads 419 on its lower portion 417 to accommodate threading the container 410 on to the lower portion 417 of water bottle 415 . Container 410 may also be divided into compartments 412 for a complete regimen of orally administered, individually packaged pharmaceutical compounds (FIG. 4 c 132 ) such as those discussed below in Migraine Kit-Type III. Preferably, a disk shaped lid 414 , with strap 416 for removal, is included to cover the contents of compartments 412 , yet permitting the secure attachment of container 410 with lid 414 to water bottle 415 . However, with or without the lid 414 , the water bottle 415 mated to container 410 provides a convenient, self contained migraine headache treatment kit.
[0032] Because, as discussed above, the most important chemical change in the brain in migraine is the decline in the level of the neurotransmitter serotonin, it is important to provide in the treatment kit 100 a means for elevating serotonin levels. To that end, preferably, a therapeutically effective dosage of a serotonin level elevating pharmaceutical compound used in the treatment of migraine is provided. Additionally, alternative methods of administering the serotonin elevating compound, such as injection devices 110 or nasal spray device 210 (shown in FIG. 2), are provided for fastest relief of symptoms associated with lower serotonin levels during a migraine attack. It should be understood that when the nasal spray device 210 is supplied, the container is manufactured such that compartment 260 fits neatly around it. When one or more injection devices 110 are used, alcohol swab packet 170 is provided for skin preparation of the migraine suffered. All modern treatment methods to treat this aspect of a migraine attack use a generic group of drugs called Triptans. One of the most popular Triptan drugs is Imitrex, manufactured by Glaxo Wellcome, now Glaxo Smith Kleine (GSK). Imitrex, i.e., Sumatriptan, is currently marketed in a tablet form (50 mg and 100 mg), a nasal spray form (20 mg) and a 6 mg injectable form, i.e. a statdose pen. In a preferred embodiment of this invention, Sumatriptan may be provided in tablet, as well as liquid forms.
[0033] While no skin patch preparation is yet available, it is within the scope of this invention to include a skin patch when a skin patch becomes available. Other available serotonin level elevating compounds which are successfully used and may, preferably, be provided by this invention include Rizatriptan, Zolmitriptan, and Almotriptan. A predetermined number of serotonin level elevating compound dosage units is provided in the manufactured drug kit 100 .
[0034] To combat the nausea and moodswings experienced by a large number of migraine sufferers, a dopamine blocking pharmaceutical compound may be prescribed. A preferred implementation of this invention provides a therapeutically effective dosage of dopamine blocking pharmaceutical compound such as Reglan, i.e., Metoclopramide, or Compazine, i.e., Prochlorperazine. A predetermined number of dopamine blocking pharmaceutical compound dosage units is provided in the manufactured drug kit 100 .
[0035] Elevated prostaglandin, associated with the severe headache caused by inflamed meninges of migraine sufferers may be combated by lowering, i.e., antagonizing the prostaglandin levels. Thus, preferably a therapeutically effective dosage of a prostaglandin inhibiting pharmaceutical compound, such as, for example, antiinflammatory drugs like Aspirin, i.e., Acetyl Salicylic Acid (325 mg to 500 mg), Tylenol (250 mg to 750 mg), i.e., Acetaminophen, Ibuprofen, and Naproxyn is provided to antagonize, i.e., lower the prostaglandin levels by inhibiting prostaglandin production of the migraine sufferer, wherein relief from the headache is obtained. A predetermined number of prostaglandin inhibiting pharmaceutical compound dosage units is provided in the manufactured drug kit 100 . It should be understood that all of the migraine treatment pharmaceutical compounds discussed above and provided in manufactured drug kit 100 may also be provided in manufactured drug kit 500 .
[0036] Listed below are preferable migraine kit compositions with sufficient dosage units, preferably, to provide treatment of at least two separate migraine attacks. It should be understood that the lists are representative examples and do not limit the scope of the migraine kit compositions.
[0037] Migraine Kit-Type I:
[0038] Imitrex (Sumatriptan) Injection ( Stat Dose Pen) quantity 2;
[0039] Imitrex (Sumatriptan) Tablet 50 mg, quantity 2;
[0040] Reglan (Metoclopromide HCL) 10 mg, quantity 2; and
[0041] Select either Ibuprofen 800 mg, quantity 2 (or) Naproxyn 500 mg, quantity 2.
[0042] Migraine Kit-Type II
[0043] Imitrex (Sumatriptan) Nasal Spray 5 mg to 20 mg, quantity 2
[0044] Imitrex (Sumatriptan) Tablets 50 mg, quantity 2
[0045] Select from either Reglan (Metoclopromide HCL) 5 mg to 10 mg, quantity 2 (or) Prochlorperazine 5 mg to 10 mg, quantity 2
[0046] Select from either Ibuprofen 400 mg to 800 mg, quantity 2 (or) Naproxyn 500 mg to 750 mg, quantity 2.
[0047] Migraine Kit-Type III
[0048] Imitrex (Sumatriptan) Tablet 100 mg, quantity 2
[0049] Imitrex (Sumatriptan) Tablet 50 mg, quantity 2
[0050] Reglan (Metoclopromide HCL) 10 mg, quantity 2
[0051] Ibuprofen 800 mg, quantity 2 (or) Naproxyn 500 mg, quantity 2
[0052] In one aspect of this invention, instead of providing the Imitrex tablet in Migraine Kit type III, one of the following compounds maybe provided:
[0053] Maxalt Tablet or MLT, 5 mg to 10 mg (Rizatriptan);
[0054] Zomig Tablet or ZMT, 2.5 mg to 5 mg (Zolmatriptan);
[0055] Axert Tablet 6.25 mg to 12.5 mg (Almotriptan).
[0056] Now that the invention has been described by way of a preferred embodiment, various modifications and improvements will occur to those of skill in the art. For example, a treatment kit of multiple pharmaceutical compounds could be prepared for the treatment of hypertension, congestive heart failure, or asthma. Thus, it should be understood that the preferred embodiment is provided as an example and not as a limitation. The scope of the invention is defined by the appended claims. | A pharmaceutical kit for treating migraine headaches and method of preparing the kit that includes a therapeutically effective dosage of pharmaceutical compounds used in the treatment of migraine headache. The pharmaceutical kit is manufactured with a predetermined number of dosage units of migraine treating pharmaceutical compounds. Additionally the kit provides all components necessary for the administering of the drugs in a safe and convenient manner. An aspect of the pharmaceutical kit may include injections and nasal sprays that are fast acting for relief of the migraine sufferer. A preferred pharmaceutical kit with only oral dosage units of drugs may be provided as an attachment to a water bottle. | 1 |
U.S. Application as Continuation of PCT/JP2009/068743
TECHNICAL FIELD
The present invention relates to a method for producing a duplex stainless steel pipe that exhibits excellent corrosion resistance even in a carbon dioxide gas corrosive environment or in a stress corrosive environment, and at the same time has a high strength. The duplex stainless steel pipe produced according to the present invention can be used for, for example, oil wells or gas wells (hereinafter, collectively referred to as “oil wells”).
BACKGROUND ART
In deep oil wells or oil wells in severe corrosive environments involving corrosive substances such as humid carbon dioxide gas (CO 2 ), hydrogen sulfide (H 2 S) or chloride ion (Cl − ), austenite-ferrite duplex stainless steel pipes having a large content of Cr such as 22Cr steel or 25Cr steel are used as oil well pipes.
These austenite-ferrite duplex stainless steels as having been subjected to the solution treatment usually applied in the production thereof can attain at most such a strength that tensile strength (TS) is of the grade of 80 kgf/mm 2 (785 MPa) and yield strength (0.2% yield stress) is of the grade of 60 kgf/mm 2 (588 MPa). In consideration of this issue, Patent Document 1 proposes a method for obtaining a high-strength duplex stainless steel pipe that contains 0.1 to 0.3% of N is subjected to a cold working with a reduction of area of 5 to 50%, and thereafter the pipe is heated at 100 to 350° C. for 30 minutes or more to yield the desired pipe. In this case, it is claimed that a duplex stainless steel pipe having a high strength is obtained by combining the work hardening due to the cold working with the aging treatment.
However, in these years, oil wells have a remarkable tendency toward being deeper, and hence, for the purpose of the use in environments severer than those hitherto experienced, it is required to produce duplex stainless steel pipes which are high in strength, in particular, of the grade of 110 to 140 ksi (the minimum yield strength is 758.3 to 965.2 MPa) and additionally have various strength levels defined in the specifications. Thus, for that purpose, it is not sufficient to consider only the content of N as in Patent Document 1, but it is also necessary to consider the contents of the other components, and additionally it is necessary to more strictly control the cold working ratio. The production method disclosed in Patent Document 1 offers a problem of the production efficiency deterioration or the cost increase due to the addition of the aging treatment step.
For the purpose of attaining a high corrosion resistance and a high strength, Patent Document 2 discloses a method in which a Cu-containing duplex stainless steel material is subjected to a cold working with a reduction of area of 35% or more, thereafter heated and quenched, and then subjected to a warm working. This document discloses a conventional example, wherein a Cu-containing duplex stainless steel wire rod is subjected to a solid-solution heat treatment and thereafter subjected to a cold working with a reduction of area of 25 to 70%, and thus a high-strength wire rod having a tensile strength of 110 to 140 kgf/mm 2 has been obtained. However, this discloses only an increase of the tensile strength due to the cold working in relation to a wire rod but not with a pipe, and hence it is not clear what is the level of the yield strength significant in the material design of the oil well pipes.
Further, Patent Document 3 describes a high strength steel that can be attained by a low-reduction cold working based on forging. However, here is merely disclosed a method for improving the strength by successively forging with a cold working ratio of about 0.5 to 1.6% over the whole region, in the longitudinal direction, of a duplex stainless steel stock that has been subjected to a solution treatment while the stock is being imparted with rotation.
[Citation List]
[Patent Documents]
[Patent Document 1] JP2-290920A
[Patent Document 2] JP7-207337A
[Patent Document 3] JP5-277611A
SUMMARY OF INVENTION
Technical Problem
As described above, any one of the above-described documents discloses the fact that the cold working enables to attain a high strength. However, these documents has never investigated specifically on the high strength attained by the cold working wherein the composition of the duplex stainless steel pipe is taken into account, and has never suggested with respect to the component design or cold working conditions appropriate to attaining the targeted strength, in particular, the targeted yield strength.
In view of these circumstances, an objective of the present invention is to provide a method for producing a duplex stainless steel pipe which has not only a corrosion resistance required for the oil well pipes used in deep oil wells or in severe corrosive environments but also a targeted strength.
Solution to Problem
For the purpose of solving the above-described problems, the present inventors produced duplex stainless steel pipes by using duplex stainless steel materials having various chemical compositions under the conditions that the working ratio in the final cold rolling was diversely varied, and performed an experiment to determine the tensile strengths of these pipes; consequently, the present inventors obtained the following findings (a) to (h).
(a) The duplex stainless steel pipes used in deep oil wells or oil wells in severe corrosive environments are required to have corrosion resistance. However, when the content of C is large, the precipitation of the carbides tends to be excessive due to the thermal effects at the time of a heat treatment, welding or the like, and hence, from the viewpoints of the corrosion resistance and the workability of the steel, in particular, from the viewpoint of the corrosion resistance, it is necessary to reduce the content of C.
(b) While the content of C is reduced, the strength comes to be insufficient without applying any other working, a material pipe produced by a hot working of the duplex stainless steel material or furthermore by a solid-solution heat treatment of the duplex stainless steel material can be improved in strength by subsequently applying cold rolling Here, it is to be noted that when the working ratio Rd exceeds 80% in terms of the reduction of area, the high strength is maintained but the work hardening occurs, and hence the ductility or the toughness is deteriorated. On the other hand, when the working ratio is less than 10% in terms of the reduction of area, no intended high strength can be attained. Consequently, it is necessary to set the working ratio of the cold rolling at 10 to 80% in terms of the reduction of area.
(c) Additionally, it has been found that when the working ratio Rd at the time of performing the cold rolling is in a range from 10 to 80% in terms of the reduction of area, the larger is the working ratio Rd of the final cold rolling in the duplex stainless steel pipe, the higher is the yield strength YS obtained for the duplex stainless steel pipe, and the relation between the working ratio Rd and the yield strength YS is represented as a linear relationship.
It has also been found that the strength of the duplex stainless steel pipe is significantly affected by the content of Cr, and the higher is the content of Cr in the steel material, the higher-strength duplex stainless steel pipe can be obtained. Further, it has also been found that the strength of the duplex stainless steel pipe is also significantly affected by the content of Mo, the content of W and the content of N, and a high-strength duplex stainless steel pipe can be produced by containing Mo, W or N.
FIG. 1 is a plot of the yield strength YS (MPa) values obtained in a tensile test against the working ratio Rd (%) values in terms of the reduction of area, for the duplex stainless steel pipes having the various chemical compositions, used in Example described below. FIG. 1 shows that there occurs a correlation between the working ratio Rd in terms of the reduction of area and the yield strength YS. FIG. 1 also shows that the higher is the content of Cr or the content of W, the higher-strength duplex stainless steel pipe can be obtained.
(d) Next, the present inventors have thought up that the yield strength of the duplex stainless steel pipe is dependent on the working ratio Rd at the time of performing the cold rolling and the chemical composition of the duplex stainless steel pipe, and accordingly it comes to be possible to establish a component design technique to be associated with the pipe working conditions, appropriate to the purpose of attaining the yield strength targeted for the duplex stainless steel pipe. In other words, for the purpose of attaining the yield strength targeted for the duplex stainless steel pipe, not the fine regulation based on the chemical composition of the duplex stainless steel pipe, but the fine regulation based on the working ratio Rd at the time of performing the cold rolling comes to be realizable. Additionally, it comes to be unnecessary to perform the melting of a large number of kinds of duplex stainless steels prepared by varying the alloy composition according to the demanded strength level, and consequently, the overstock of the material billets can be suppressed.
As described above, when the appropriate component design technique associated with the pipe working conditions can be established, it is only required to perform the cold rolling, for the purpose of obtaining a duplex stainless steel pipe having a targeted strength, under the cold rolling conditions targeted by taking account of the alloy composition of the stock, namely, with the targeted working ratio Rd or the higher working ratio than the targeted working ratio, without being required to vary the alloy composition of the stock on a case-by-case basis.
(e) On the basis of such an idea as described above, the present inventors have continuously made a diligent study on the correlations among the yield strength of the duplex stainless steel pipe, the working ratio Rd at the time of performing the cold rolling and the chemical composition of the duplex stainless steel pipe. Consequently, it has been found that when the working ratio Rd at the time of performing the cold rolling falls within a range from 10 to 80% in terms of the reduction of area, the yield strength YS (MPa) of the duplex stainless steel pipe can be calculated on the basis of the working ratio Rd at the time of performing the cold rolling and the individual contents of Cr, Mo, W and N in the chemical composition of the duplex stainless steel pipe, and on the basis of the following formula (2):
YS= (14.5×Cr+48.3×Mo+20.7×W+6.9×N)×( Rd ) 0.195 (2)
wherein YS and Rd signify the yield strength (MPa) and the working ratio (%) in terms of the reduction of area, respectively, and Cr, Mo, W and N signify the contents (mass %) of the respective elements.
In general, examples of the method of cold working include a cold drawing using a drawing machine with a die and a plug and a cold rolling using a pilger mill with roll-dies and a mandrel. However, the present inventors have found that even when the working ratios determined by the same reduction of area are concerned, the strength of the pipe obtained by cold drawing is higher than the strength of the pipe of the present invention obtained by cold rolling, and the above-described formula (2) is not applicable to the relationship between the working ratio Rd in the cold drawing and the yield strength YS (MPa). Consequently, in the present invention, the production method is restricted to the method for producing a high alloy pipe through a step of cold rolling.
FIG. 2 is a plot of the yield strength YS (MPa) values actually obtained by a tensile test against the values obtained by substituting, into the right side of the above-described formula (2), the chemical compositions and the working ratios Rd (%) in terms of the reduction of area, for the various duplex stainless steel pipes used in Example described below, wherein the abscissa represents the value of the right side of formula (2) and the ordinate represents the YS. FIG. 2 shows that as far as the duplex stainless steel pipe is concerned, the yield strength of the duplex stainless steel pipe can be obtained with a satisfactory accuracy, according to formula (2), from the chemical composition of the duplex stainless steel pipe and the working ratio Rd (%) in terms of the reduction of area for the duplex stainless steel pipe.
(f) Accordingly, for the purpose of obtaining a duplex stainless steel pipe having a targeted strength, it is only required to develop, by the cold rolling, the yield strength fraction exclusive of the yield strength developed by the alloying components of the stock, namely, by the contents of Cr, Mo, W and N. Thus, for the purpose of attaining the targeted yield strength MYS (grade of 110 to 140 ksi (the minimum yield strength is 758.3 to 965.2 MPa)), after the selection of the chemical composition of the duplex stainless steel pipe, it is only required to perform the final cold rolling with the working ratio Rd (%) obtained from the above-described formula (2) or the working ratio larger than this working ratio. Consequently, it is only required to perform the cold rolling under the conditions that the working ratio Rd, in terms of the reduction of area in the final cold rolling step, falls within a range from 10 to 80% and additionally the following formula (1) is satisfied:
Rd =exp[{In( MYS )−In(14.5×Cr+48.3×Mo+20.7×W+6.9×N)}/0.195] (1)
wherein Rd and MYS signify the working ratio (%) in terms of the reduction of area and the targeted yield strength (MPa), respectively, and Cr, Mo, W and N signify the contents (mass %) of the individual elements, respectively.
(g) It has also been found that for the purpose of obtaining a duplex stainless steel pipe having a higher strength, namely, a duplex stainless steel pipe having a targeted yield strength MYS (grade of 125 to 140 ksi (the minimum yield strength is 861.8 to 965.2 MPa)), it is only required to regulate the working ratio Rd in terms of the reduction of area in the final cold rolling step to fall particularly within a range from 25 to 80%, or to increase the content of Mo and the content of W in the duplex steel so as to fall within a range from 2 to 6 mass % and within a range from 1.5 to 6 mass %, respectively. Further, it has also been found that when the working ratio Rd in terms of the reduction of area in the final cold rolling step is regulated to fall within a range from 25 to 80% and the content of Mo and the content of W in the duplex steel are increased so as to fall within a range from 2 to 6 mass % and within a range from 1.5 to 6 mass %, respectively, it is possible to produce a duplex stainless steel pipe in which the targeted yield strength is of a higher grade of 140 ksi (the minimum yield strength is 965.2 MPa).
(h) As described above, for the duplex stainless steel pipe, without excessively adding the alloying components, by selecting the cold working conditions, the targeted yield strength can be attained. Consequently, the reduction of the raw material cost can be achieved. Further, by selecting the cold working conditions in conformity with the alloy composition of the stock, the duplex stainless steel pipe having the targeted strength can be obtained, and hence it comes to be unnecessary to perform the melting of a large number of kinds of duplex stainless steels by varying the alloy composition depending on the strength level. Accordingly, the overstock of the material billets can be suppressed.
The present invention has been perfected on the basis of such new findings as described above, and the gist of the present invention is as described in the following items (1) to (4).
(1) A method for producing a duplex stainless steel pipe having a minimum yield strength of 758.3 to 965.2 MPa, comprising:
preparing a duplex stainless steel material pipe for cold working, having a chemical composition consisting, by mass %, of C: 0.03% or less, Si: 1% or less, Mn: 0.1 to 4%, Cr: 20 to 35%, Ni: 3 to 10%, Mo: 0 to 6%, W: 0 to 6%, Cu: 0 to 3% and N: 0.15 to 0.60%, and the balance being Fe and impurities, by a hot working or further by a solid-solution heat treatment; and
producing the duplex stainless steel pipe by subsequently subjecting the material pipe to a cold rolling,
wherein the cold rolling is performed under the conditions that the working ratio Rd, in terms of the reduction of area, in the final cold rolling step falls within a range from 10 to 80%, and the following formula (1) is satisfied:
Rd =exp[{In( MYS )−In(14.5×Cr+48.3×Mo+20.7×W+6.9×N)}/0.195] (1)
wherein Rd and MYS signify the working ratio (%) in terms of the reduction of area and the targeted yield strength (MPa), respectively, and Cr, Mo, W and N signify the contents (mass %) of the individual elements, respectively.
(2) A method for producing a duplex stainless steel pipe having a minimum yield strength of 861.8 to 965.2 MPa, comprising:
preparing a duplex stainless steel material pipe for cold working, having a chemical composition consisting, by mass %, of C: 0.03% or less, Si: 1% or less, Mn: 0.1 to 4%, Cr: 20 to 35%, Ni: 3 to 10%, Mo: 0 to 6%, W: 0 to 6%, Cu: 0 to 3% and N: 0.15 to 0.60%, and the balance being Fe and impurities, by a hot working or further by a solid-solution heat treatment; and
producing the duplex stainless steel pipe by subsequently subjecting the material pipe to a cold rolling,
wherein the cold rolling is performed under the conditions that the working ratio Rd, in terms of the reduction of area, in the final cold rolling step falls within a range from 25 to 80%, and the following formula (1) is satisfied:
Rd =exp[{In( MYS )−In(14.5×Cr+48.3×Mo+20.7×W+6.9×N)}/0.195] (1)
wherein Rd and MYS signify the working ratio (%) in terms of the reduction of area and the targeted yield strength (MPa), respectively, and Cr, Mo, W and N signify the contents (mass %) of the individual elements, respectively.
(3) A method for producing a duplex stainless steel pipe having a minimum yield strength of 861.8 to 965.2 MPa, comprising:
preparing a duplex stainless steel material pipe for cold working, having a chemical composition consisting, by mass %, of C: 0.03% or less, Si: 1% or less, Mn: 0.1 to 4%, Cr: 20 to 35%, Ni: 3 to 10%, Mo: 2 to 6%, W: 1.5 to 6%, Cu: 0 to 3% and N: 0.15 to 0.60%, and the balance being Fe and impurities, by a hot working or further by a solid-solution heat treatment; and
producing the duplex stainless steel pipe by subsequently subjecting the material pipe to a cold rolling, wherein the cold rolling is performed under the conditions that the working ratio Rd, in terms of the reduction of area, in the final cold rolling step falls within a range from 10 to 80%, and the following formula (1) is satisfied:
Rd =exp[{In( MYS )−In(14.5×Cr+48.3×Mo+20.7×W+6.9×N)}/0.195] (1)
wherein Rd and MYS signify the working ratio (%) in terms of the reduction of area and the targeted yield strength (MPa), respectively, and Cr, Mo, W and N signify the contents (mass %) of the individual elements, respectively.
(4) A method for producing a duplex stainless steel pipe having a minimum yield strength of 965.2 MPa, comprising:
preparing a duplex stainless steel material pipe for cold working, having a chemical composition consisting of, by mass %, C: 0.03% or less, Si: 1% or less, Mn: 0.1 to 4%, Cr: 20 to 35%, Ni: 3 to 10%, Mo: 2 to 6%, W: 1.5 to 6%, Cu: 0 to 3% and N: 0.15 to 0.60%, and the balance being Fe and impurities, by a hot working or further by a solid-solution heat treatment; and
producing the duplex stainless steel pipe by subsequently subjecting the material pipe to a cold rolling, wherein the cold rolling is performed under the conditions that the working ratio Rd, in terms of the reduction of area, in the final cold rolling step falls within a range from 25 to 80%, and the following formula (1) is satisfied:
Rd =exp[{In( MYS )−In(14.5×Cr+48.3×Mo+20.7×W+6.9×N)}/0.195] (1)
wherein Rd and MYS signify the working ratio (%) in terms of the reduction of area and the targeted yield strength (MPa), respectively, and Cr, Mo, W and N signify the contents (mass %) of the individual elements, respectively.
In the chemical compositions of the duplex stainless steel materials used in the present invention, the “impurities” in the balance being “Fe and impurities” mean the substances that contaminate the steel materials when duplex stainless steel pipes are industrially produced, due to the raw materials such as ores and scraps, and due to various other factors in the production process, and are allowed to contaminate within the ranges not adversely affecting the present invention.
Advantageous Effects of Invention
According to the present invention, a duplex stainless steel pipe not only having the corrosion resistance required for oil well pipes used in deep oil wells or in severe corrosive environments but also a targeted strength can be produced without excessively adding alloying components, by selecting the cold working conditions.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is the plots, for duplex stainless steel pipes, of the yield strength YS (MPa) values obtained in a tensile test against the working ratio Rd (%) values in terms of the reduction of area.
FIG. 2 is a plot, for duplex stainless steel pipes, of the yield strength YS (MPa) values obtained by a tensile test against the values obtained by substituting, into the right side of the above-described formula (2), the chemical compositions and the working ratios Rd (%) in terms of the reduction of area, wherein the abscissa represents the value of the right side of formula (2) and the ordinate represents the YS.
DESCRIPTION OF EMBODIMENTS
Next, description is made on the reasons for limiting the chemical composition of the duplex stainless steel material used in the method for producing a duplex stainless steel pipe according to the present invention. Here, it is to be noted that “%” in each of the contents of the individual elements represents “mass %.”
C: 0.03% or Less
C is an element that has an effect to stabilize the austenite phase to improve the strength, and also has an effect to obtain a microstructure by precipitating carbides at the time of the temperature increase in the heat treatment. However, when the content of C exceeds 0.03%, the precipitation of the carbides comes to be excessive due to the thermal effects at the time of a heat treatment or welding, and thus the corrosion resistance and the workability of the steel are deteriorated. Consequently, the upper limit of the content of C is set at 0.03%. The upper limit of the content of C is preferably 0.02%.
Si: 1% or Less
Si is an element that is effective as a deoxidizer, and also has an effect to obtain a microstructure by precipitating an intermetallic compound at the time of temperature increase in the heat treatment, and hence Si can be contained if necessary. These effects are obtained for the content of Si of 0.05% or more. However, when the content of Si exceeds 1%, the precipitation of the intermetallic compound comes to be excessive due to the thermal effects at the time of a heat treatment or welding, and thus the corrosion resistance and the workability of the steel are deteriorated, and consequently, the content of Si is set at 1% or less. The range of the content of Si is preferably 0.7% or less.
Mn: 0.1 to 4%
Mn is an element that is effective as a deoxidizer similarly to Si as described above, and at the same time fixes S, inevitably contained in the steel, as a sulfide to improve the hot workability. The effect of Mn is obtained with the content of Mn of 0.1% or more. However, when the content of Mn exceeds 4%, the hot workability is deteriorated, and additionally the corrosion resistance is adversely affected. Consequently, the content of Mn is set at 0.1 to 4%. The range of the content of Mn is preferably from 0.1 to 2% and more preferably 0.3 to 1.5%.
Cr: 20 to 35%
Cr is a fundamental component that is effective in maintaining the corrosion resistance and improving the strength. For the purpose of attaining these effects, it is necessary to set the content of Cr at 20% or more. However, when the content of Cr exceeds 35%, the σ-phase tends to be precipitated, and both of the corrosion resistance and the toughness are deteriorated. Consequently, the content of Cr is set at 20 to 35%. For the purpose of obtaining a higher strength, the content of Cr is preferably 23% or more. On the other hand, from the viewpoint of the toughness, the content of Cr is preferably 28% or less.
Ni: 3 to 10%
Ni is an element that is contained to stabilize the austenite phase and to obtain a duplex microstructure. When the content of Ni is less than 3%, the ferritic phase predominates and no duplex microstructure is obtained. On the other hand, when the content of Ni exceeds 10%, austenite phase predominates and no duplex microstructure is obtained, and additionally the economy is impaired because Ni is an expensive element, and hence the content of Ni is set at 3 to 10%. It is preferable to set the upper limit of the content of Ni at 8%.
Mo: 0 to 6% (Inclusive of 0%)
Mo is an element that improves the pitting resistance and the crevice corrosion resistance, and at the same time improves the strength through solid-solution strengthening, and hence Mo can be contained if necessary. When it is intended to obtain the effect of Mo, Mo is preferably contained in a content of 0.5% or more. On the other hand, when Mo is contained excessively, the σ-phase tends to be precipitated and the toughness is deteriorated. Consequently, the content of Mo is preferably set at 0.5 to 6%. When it is intended to obtain a duplex stainless steel pipe having a higher strength, the content of Mo is preferably set at 2 to 6%, and when it is intended to further stabilize the micro-structure and the toughness, the content of Mo is more preferably set at 2 to 4%.
W: 0 to 6% (Inclusive of 0%)
W is an element that, similarly to Mo, improves the pitting resistance and the crevice corrosion resistance, and at the same time improves the strength through solid-solution strengthening, and hence W can be contained if necessary. When it is intended to obtain the effect of W, W is preferably contained in a content of 0.5% or more. On the other hand, when Mo is contained excessively, the σ-phase tends to be precipitated and the toughness is deteriorated. Consequently, the content of W is preferably set at 0.5 to 6%. When it is intended to obtain a duplex stainless steel pipe having a higher strength, the content of W is more preferably set at 1.5 to 6%.
As described above, both Mo and W are not necessarily required to be contained; however, either one or both of Mo and W can be contained. When either one of Mo and W is contained, the preferable contents of Mo and W and the more preferable contents of Mo and W are as described above. When both of Mo and W are contained, it is preferable to set the content of Mo at 0.5 to 6% and the content of W at 0.5 to 6%. When it is intended to obtain a duplex stainless steel pipe having a higher strength, it is more preferable to set the content of Mo at 2 to 6% and the content of W at 1.5 to 6%.
Cu: 0 to 3% (Inclusive of 0%)
Cu is an element that improves the corrosion resistance and the grain boundary corrosion resistance, and Cu can be contained if necessary. When it is intended to obtain the effect of Cu, Cu is preferably contained in a content of 0.1% or more and more preferably in a content of 0.3% or more. However, when the content of Cu exceeds 3%, the effect of Cu is saturated, and adversely the hot workability and the toughness are deteriorated. Consequently, when Cu is contained, the content of Cu is set preferably at 0.1 to 3% and more preferably at 0.3 to 2%.
N: 0.15 to 0.60%
N is an element that enhances the stability of austenite phase, and at the same time enhances the pitting resistance and the crevice corrosion resistance of the duplex stainless steel. Additionally, similarly to C, N has an effect to stabilize the austenite phase and to thereby improve the strength, and hence is an important element for the present invention that attains a high strength. When the content of N is less than 0.15%, no sufficient effect of N is obtained. On the other hand, when the content of N exceeds 0.60%, the toughness and the hot workability are deteriorated, and consequently, the content of N is set at 0.15 to 0.60%. For the purpose of obtaining a higher strength, the lower limit of the content of N is preferably set so as to exceed 0.17%. The upper limit of the content of N is preferably set at 0.35%. The content of N is more preferably 0.20 to 0.30%.
Moreover, on the basis of the below-described reasons, P, S and 0 contained as the impurities are preferably limited in such a way that P: 0.04% or less, S: 0.03% or less and O: 0.010% or less.
P: 0.04% or Less
P is contained as an impurity, and when the content of P exceeds 0.04%, the hot workability is deteriorated, and the corrosion resistance and the toughness are also deteriorated. Consequently, the upper limit of the content of P is preferably set at 0.04%.
S: 0.03% or Less
S is contained as an impurity, similarly to P as described above, and when the content of S exceeds 0.03%, the hot workability is remarkably deteriorated, and additionally, sulfides function as the starting points of the occurrence of pitting to impair the pitting resistance. Consequently, the upper limit of the content of S is preferably set at 0.03%.
O: 0.010% or Less
In the present invention, N is contained in such a larger amount as 0.15 to 0.60%, and hence the hot workability tends to be deteriorated. Consequently, the content of O is preferably set at 0.010% or less.
The duplex stainless steel according to the present invention may further contain one or more of Ca, Mg and the rare earth elements (REMs), in addition to the above-described elements. The reasons why these elements may be contained and the contents of these elements when these elements are contained are as follows.
Ca: 0.01% or Less, Mg: 0.01% or Less and Rare Earth Element(s) (REM(s)): 0.2% or Less of One or More Elements
These components can be contained if necessary. When contained, any of these components fixes S that disturbs the hot workability, as a sulfide, and thus has an effect to improve the hot workability. However, when the content of either of Ca and Mg exceeds 0.01%, or the content of the REM(s) exceeds 0.2%, coarse oxides are produced, and the deterioration of the hot workability is caused. Accordingly, when these elements are contained, the upper limits of these elements are set at 0.01% for Ca and Mg, and 0.2% for the REM(s), respectively. It is to be noted that for the purpose of certainly developing the improving effect of the hot workability, it is preferable to contain Ca and Mg each in a content of 0.0005% or more and the REM(s) in a content of 0.001% or more. Herein, the REM is a generic name for the 17 elements which are the 15 lanthanoid elements and Y and Sc, and one or more of these elements can be contained. The content of REMs means the sum of the contents of these elements.
The duplex stainless steel pipe of the present invention contains the above-described essential elements and additionally the above-described optional elements, the balance being Fe and impurities, and can be produced by the production equipment and the production method used for the usual commercial production. For example, for the melting of the duplex stainless steel, there can be used an electric furnace, an Ar—O 2 mixed gas bottom blowing decarburization furnace (AOD furnace), a vacuum decarburization furnace (VOD furnace) or the like. The molten steel obtained by melting may be cast into ingots, or may be cast into rod-like billets by a continuous casting method. By using these billets, with an extrusion pipe production method such as the Ugine-Sejournet process or with a hot working such as the Mannesmann pipe making process, a duplex stainless steel material pipe for cold working can be produced. The material pipe after the hot working is converted into a product pipe having an intended strength by cold rolling.
In the present invention, the working ratio at the time of the final cold working is specified, the material pipe for cold working, obtained by the hot working, is subjected to a solid-solution heat treatment if necessary, and thereafter the descaling for removing the scales on the pipe surface is performed, and thus a duplex stainless steel pipe having an intended strength may be produced by one run of cold working. Alternatively, before the final cold working, the solid-solution heat treatment is performed by conducting one or more runs of intermediate cold working, and the final cold rolling may be performed after descaling. By performing an intermediate cold working, the working ratio in the final cold rolling is easily controlled, and at the same time, as compared to the case where the cold working is applied in the state of having been subjected to the hot working, a pipe having a higher-accuracy pipe dimension can be obtained by the final cold working.
EXAMPLE 1
First, the duplex stainless steels having the chemical compositions shown in Table 1 were melted with an electric furnace, and were regulated with respect to the components so as to have approximately the intended chemical compositions, and then, the melting was performed by a method in which by using an AOD furnace, a decarburization treatment and a desulfurization treatment were conducted. Each of the obtained molten steels was cast into an ingot having a weight of 1500 kg and a diameter of 500 mm. Then, the ingot was cut to a length of 1000 mm to yield a billet for use in the extrusion pipe production. Next, by using this billet, a material pipe for cold working was formed by the hot extrusion pipe production method based on the Ugine-Sejournet process.
TABLE 1
Test
Chemical composition (mass %, the balance: Fe and impurities)
No.
C
Si
Mn
P
S
Cr
Ni
Mo
W
Cu
N
1
0.017
0.31
0.49
0.025
0.0006
24.81
6.56
3.07
2.08
0.50
0.272
2
0.017
0.31
0.49
0.025
0.0006
24.81
6.56
3.07
2.08
0.50
0.272
3
0.017
0.31
0.49
0.025
0.0006
24.81
6.56
3.07
2.08
0.50
0.272
4
0.017
0.31
0.49
0.025
0.0006
24.81
6.56
3.07
2.08
0.50
0.272
5
0.016
0.30
0.50
0.024
0.0006
25.00
6.70
3.15
2.10
0.50
0.280
6
0.016
0.30
0.50
0.024
0.0006
25.00
6.70
3.15
2.10
0.50
0.280
7
0.016
0.30
0.50
0.024
0.0006
25.00
6.70
3.15
2.10
0.50
0.280
8
0.016
0.30
0.50
0.024
0.0006
25.00
6.70
3.15
2.10
0.50
0.280
9
0.023
0.40
1.20
0.028
0.0005
22.50
5.10
3.20
0.12
0.20
0.175
10
0.023
0.40
1.20
0.028
0.0005
22.50
5.10
3.20
0.12
0.20
0.175
Each of the obtained material pipes for cold working was subjected to an intermediate cold working, and thereafter subjected to a solution heat treatment under the conditions that water-cooling was performed after being held at 1050 to 1120° C. for 2 minutes or more. Thereafter, the working ratio Rd (%) in terms of the reduction of area was varied so as to have different values as shown in Table 2, and further the final cold working based on the cold rolling using a pilger mill was performed, and thus a duplex stainless steel pipe was obtained. It is to be noted that before the cold rolling was performed, a shotblast was applied to the pipe, and thus the scales on the surface were removed. The dimensions (the outer diameter in mm×the wall thickness in mm) of each of the pipes before and after the final cold working are shown in Table 2.
TABLE 2
Dimensions before the
Dimensions after the
final cold rolling
final cold rolling
Right side
Test
(Outer diameter ×
(Outer diameter ×
of Formula
Obtained value
No.
wall thickness)
wall thickness)
Rd (%)
(2) (MPa)
YS (MPa)
TS (MPa)
1
102 × 6.6
63.5 × 6.6
39.9
1134.7
1144.4
1268.5
2
102 × 6.6
63.5 × 5.5
48.5
1178.7
1192.7
1289.2
3
102 × 6.6
63.5 × 4.2
59.3
1225.8
1227.1
1323.7
4
102 × 6.6
63.5 × 3.2
68.5
1260.8
1261.6
1365.0
5
46.5 × 7.25
25.5 × 3.25
75.0
1299.8
1282.3
1371.9
6
70 × 6.5
63.5 × 6.5
10.2
880.8
861.8
965.2
7
70 × 6.5
63.5 × 5.7
20.3
1007.4
992.7
1068.6
8
70 × 6.5
63.5 × 4.9
30.3
1089.2
1082.4
1137.5
9
68.5 × 8.0
51.0 × 8.0
28.9
933.6
941.0
1006.5
10
68.5 × 9.25
51.0 × 8.0
37.2
980.7
985.9
1027.2
Thereafter, from the obtained duplex stainless steel pipes, arc-shaped tensile test specimens in the pipe axis direction were sampled, and subjected to a tensile test. The observed values as the results of the test, namely, the yield strength YS (MPa) (0.2% yield stress) values and the tensile strength TS (MPa) values in the tensile test are shown in Table 2 together with the numerical values based on the right side of formula (2).
As shown in Table 2, by appropriately selecting the alloy composition and the working ratio Rd in terms of the reduction of area in the cold rolling step, a high alloy pipe having a high strength with a minimum yield strength of 758.3 to 965.2 MPa (grade of 110 to 140 ksi) as the targeted strength can be produced. Further, by setting the working ratio Rd within a range from 25 to 80%, or by increasing the content of Mo and the content of W in the duplex stainless steel to be 2 to 4% and 1.5 to 6%, respectively, a duplex stainless steel pipe having a further higher strength can be produced.
[Industrial Applicability]
The results are as described above, and hence, according to the present invention, a duplex stainless steel pipe that has not only a corrosion resistance that is required for the oil well pipes used in deep oil wells or in severe corrosive environments, but also a targeted strength can be produced, without excessively adding alloying components, by selecting the cold working conditions. | A method for producing a duplex stainless steel pipe having a minimum yield strength of 758.3 to 965.2 MPa, comprises first hot working and optionally solution heat treating a duplex stainless steel material pipe having a chemical composition consisting, by mass %, of C: 0.03% or less, Si: 1% or less, Mn: 0.1 to 4%, Cr: 20 to 35%, Ni: 3 to 10%, Mo: 0 to 6%, W: 0 to 6%, Cu: 0 to 3% and N: 0.15 to 0.60%, the balance being Fe and impurities. The pipe is then cold rolled under conditions that the working ratio Rd, in terms of the reduction of area, in the final cold rolling step falls within a range from 10 to 80%, and formula (1) is satisfied:
Rd =exp[{In( MYS )−In(14.5×Cr+48.3×Mo+20.7×W+6.9×N)}/0.195] (1)
wherein Rd is a reduction in area %, MYS is the targeted yield strength (MPa), and Cr, Mo, W and N are in mass %. | 2 |
METHOD AND APPARATUS
The invention relates to a dynamic control and decision making method and apparatus for an image analyzer and more particularly to a method and apparatus that improves system performance of an automated, image based biological specimen analysis system by increasing processing speed and prescreening accuracy.
BACKGROUND OF THE INVENTION
Systems that process image data at rates acceptable for automated diagnostic prescreening, automated diagnostic screening and automated diagnostic screening quality control include the system disclosed in U.S. Pat. No. 5,315,700, entitled “Method And Apparatus For Rapidly Processing Data Sequences”, by Richard S. Johnston et al. issued May 24, 1994 which is incorporated by reference hereto. These systems process images of biological specimen slides such as Pap smear slides. The biological specimen is taken from a patent that is part of a patient population. These systems automatically review the slide and provide an analysis score. The performance of these systems and similar image analysis systems depend on many factors including: the cellular materials composition of the slides to be screened; the speed of the system to scan and process images; the regular patient population composition; the operational mode of the system including system specificity and system sensitivity; and the variations between specimens. The slide processing speed of such systems determines their capacity and thus their operational cost. These systems also have associated signal to noise characteristics. The signal comprises the abnormal cellular material on the processed slides. The noise comprises the artifact or normal cellular material misclassified as abnormal material by these systems. Poor signal to noise characteristics adversely effect the classification effectiveness of these systems.
For example, the task of examining biological specimen slides for the prescreening of cervical cancer demonstrates the need for increasing processing speed and accuracy of automated specimen screeners. Each biological specimen slide exhibits large variability in abnormal cell prevalence. To routinely achieve the high sensitivity required on low-prevalence abnormal specimens, specimens that have a low number of abnormal material, these systems must process a significant number, if not all, of the images taken of the biological specimen slide. Consequently, the number of images these systems must process determines system throughput. In the prior art, the number of images to process is predetermined based on predefined criteria. As a result, the prior art treated each biological specimen slide identically, disregarding data collected from the slide during processing, using a simple sequential test methodology. In some instances this may degrade the signal to noise characteristics of the analysis by including noisy information. The invention recognizes for the first time that an automated analysis achieves optimum signal to noise characteristics during processing. The invention further determines when to stop processing to prevent counterproductive analysis.
Therefore, the invention dynamically processes the biological specimen slide based on data collected from the slide to achieve higher accuracy as well as increased system throughput.
SUMMARY OF THE INVENTION
The invention provides a dynamic decision making method for processing a biological specimen. A computer acquires an image of the biological specimen. The computer processes the image to extract a feature from the image. Using the extracted feature, the computer dynamically chooses additional image processing modules to operate on the image from a predetermined set of image processing modules. The computer may further dynamically adjust the image processing steps performed on the image. The computer then determines whether to acquire a second image and selects the image modules to operate on the second image. The invention thereby provides for enhanced throughput by avoiding unnecessary additional computation.
The invention further provides a dynamic slide classifier for improving system performance of an automated system by increasing processing speed and prescreening accuracy. The dynamic slide classifier includes a means for slide scoring having a process control input and a slide score processing result output; and a means for process control connected to the slide score processing result output, wherein the means for process control is connected to the process control input. In one embodiment, the means for slide scoring further comprises: means for image focusing and acquisition having an image output; means for image processing and feature extraction connected to the image output having a processed image output; and means for processing the processed image output having a control input connected to the process control input. In an alternate embodiment, the means for process control further comprises: means for score calculating connected to the slide score processing result output, wherein the means for score calculating has a review specimen output and a normal specimen output; means for making an automatic inference connected to the slide score processing result output; and means for controlling the means for slide scoring having a control output connected to the process control input.
The invention also provides a method of image scanning and processing comprising the steps of: scanning and processing images based on a current prioritized image scan sequence; terminating slide processing when a classification decision is made; changing the current prioritized image scan sequence to a new prioritized scan sequence; disabling a subset of image processing to reduce unnecessary computation; enabling a new set of image processing to collect new information from the slide; and rescanning and processing certain areas using different image processing.
Other objects, features and advantages of the present invention will become apparent to those skilled in the art through the description of the preferred embodiment, claims and drawings herein wherein like numerals refer to like elements.
BRIEF DESCRIPTION OF THE DRAWINGS
To illustrate this invention, a preferred embodiment will be described herein with reference to the accompanying drawings.
FIG. 1 shows the control process module of the invention in a hardware schematic diagram.
FIGS. 2A and 2B show the method of the invention to dynamically control automated sorting of biological specimens.
FIGS. 2C, 2 D and 2 E show the scan sequences of the invention.
FIGS. 3A, 3 B and 3 C show one embodiment of the invention.
FIGS. 4A and 4B show the method and apparatus of the invention to dynamically control an automated cytology system.
FIG. 5 shows the method of the invention to perform an image processing decision based on the result of an image feature extracted from an image.
FIG. 6 shows the method of the invention to decide whether or not to acquire another image of the biological specimen.
FIG. 7 shows the method of the invention to decide whether or not to continue image processing or perform an additional image processing step.
FIG. 8 shows the method of the invention to decide whether to continue slide processing or perform an additional slide processing step.
FIG. 9 shows the method of the invention to decide whether to rescan and process different areas of the slide using different image processing steps.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Refer now to FIG. 1 which shows a schematic diagram of the apparatus of the invention. The dynamic decision making system 22 comprises a Control Process Module CPM 24 and an image analysis system 48 . The CPM 24 controls the operation of an image analysis system 48 . The dynamic decision making system 22 may comprise an image based biological specimen analysis system, an automated diagnostic prescreener, an automated diagnostic screener, or an automated diagnostic screening quality control system. One example embodiment of an image based biological specimen analysis system is shown in FIGS. 3A, 3 B and 3 C. The CPM 24 controls the image analysis system 48 though control line 44 and receives information from the image analysis system 48 through processing results line 46 . The execution unit 28 receives a raw score signal on raw score line 27 from score calculators 26 and a control input 29 from control logic 32 to direct the control of the analysis system 48 . The execution unit 28 generates a control signal on control line 44 . The control line 44 transmits operational commands to the image analysis system 48 that change the type of processing performed on the image data obtained by the image analysis system 48 . In one embodiment of the invention, the image analysis system transmits processing results on processing results line 46 . The image scanning and processing module ISPM 49 transmits slide image features to the CPM 24 .
The CPM 24 processes the processing results, such as image features, using a data-driven control mechanism. The CPM 24 dynamically controls the image analysis system 48 based on the processing results. CPM 24 employs decision making methods that flexibly determine the image processing modules or steps needed to perform an effective image analysis. For example, in a biological specimen analysis system the dynamic control and decision making method of the invention flexibly determines the processing steps needed to reach a confident classification decision about each biological specimen.
The data-driven control mechanism of the invention improves system accuracy and reduces unnecessary or even counterproductive computation thereby enhancing system throughput, thus increasing the economic value of the system. In addition, by reducing counterproductive computation, the invention tries to maximize the signal to noise characteristics of the system.
There is a point during image processing where further processing becomes counterproductive. The invention finds this processing point. At this point processing is halted and the classification decision is made.
The CPM 24 controls the operation of the image analysis system 48 , which in another embodiment of the invention may be an image scanning and processing module, based on data already gathered about the specimen. The CPM 24 monitors the progress of the analysis and interacts with the processing being performed by the image analysis system 48 . FIG. 1 illustrates the interactive process connection between image analysis system 48 and the CPM 24 .
In one embodiment of the invention, the CPM 24 comprises a set of predetermined control logic driven by an execution unit 28 to determine the actions performed by the image analysis system 48 . Those skilled in the art will appreciate that the predetermined control logic may be embodied in software, written in the C programming language for example, running on a CPU such as a general purpose computer, personal computer, or workstation. The execution unit 28 is connected to the image analysis system 48 . The execution unit 28 receives processing results from process result line 46 and controls the image analysis engine 48 through control line 44 . The execution unit 28 , in one embodiment, is an expert system that runs in software on a SUN workstation, personal computer or general purpose computer.
One embodiment of the image analysis system 48 is shown in FIGS. 3A, 3 B and 3 C. The automatic image focusing and acquisition device 516 coupled with an image processor and feature-extractor 536 implements a set of process steps that use the image processor and feature-extractor 536 to segment the image, calculate features from the segmented objects, and classify them as objects of interest, i.e., abnormal cells, or endocervical component cells. In one embodiment of the invention, image scanning and processing is a sequential process. After i images are scanned and processed, the system reaches the decision point i. At each decision point i of the process, the CPM 24 will do either one or a combination of several of the steps below:
(1) command the image processing system 48 to continue to scan and process more images based on a current prioritized image scan sequence, or
(2) command the image processing system 48 to terminate slide processing because the specimen classification decision has been made, or
(3) change the current prioritized image scan sequence to a new prioritized scan sequence, or
(4) disable a subset of image processing steps in the image processing system 48 to reduce unnecessary computation, or
(5) enable a new set of image processing steps in the image processing system 48 to collect new information from the slide, or
(6) rescan and process certain areas, such as Regions of Interest ROI's where ambiguous alarms were found, using a different set of processing steps.
For example, as applied to the application of Pap Smear prescreening, the decision of sorting slides as normal or review depends on the detection of adequate endocervical components and squamous cells, and the detection of abnormal cells. A slide will be declared as clearly normal 54 if adequate endocervical components and squamous cells are detected, and no abnormal cells are detected. Otherwise, the slide is sorted out as review 52 .
Slide processing starts with the determination of a prioritized scan sequence. The priorities used to create the sequence can be based on, for each subarea of a slide, the evaluated probabilities of containing either endocervical components, or abnormal cells, or both, in each subarea of the slide. Then, the CPM 24 initiates the image analysis system 48 to process the slide following a selected prioritized scan sequence.
According to the control logic 32 the slide processing continues until the CPM 24 reaches a decision of either rejecting the slide for human review or accepting it as a clearly normal slide. According to one embodiment of the invention, certain slide processing steps terminate when sufficient information of a certain type, such as an adequate number of normal endocervical component cells have been detected. In one embodiment, this is a predetermined value based on maximizing the system's sensitivity to slides with endocervical components and with fixed system specificity of slides without endocervical components.
For example, a system may achieve 90% sensitivity with 90% specificity. The subsequent scan sequence will be changed to scan areas having higher probability of abnormality alone. These areas are identified in the initial prioritization scan of the slide. Also, since there is no need to detect more endocervical components, a predetermined subset of image processing steps for the endocervical cell classification are disabled in the ISPM 49 . A new set of image processing steps are enabled when certain types of information have been detected, such as an abundance of small objects in the size range of polymorphonucleocytes. The detection of this condition triggers the need to check for certain other conditions on the slide. A set of new processing steps are then activated in the image analysis system 48 to determine whether those conditions such as infections are present or not. The typical new steps are designed to classify small size objects such as polymorphonucleocytes. Areas of the slide are rescanned and reprocessed when inconclusive conditions such as low confidence abnormal cells and alarms are detected on the slide that require further analysis to drive the final slide sorting decision. The areas containing the detected low-confidence alarms will be rescanned, optionally in higher magnification, and analyzed by a different set of processing steps.
In one embodiment of the invention, the CPM 24 employs a dynamic score-thresholding method. In the dynamic score-thresholding method of the invention a rule-based control system such as a simple confidence or score-thresholding method determines the nature of further image processing. The system control process does not dynamically determine what area of a specimen to scan and process by the scanning and processing module, instead, it follows a predetermined ordering before the scan and process sequences begin. The order may reflect the difference of probabilities of different types of abnormality conditions.
In one embodiment of the invention, the image processing system 48 comprises an image scanning and processing module ISPM 49 . The ISPM 49 may signal the termination of CPM 24 processing. While processing a specimen, the CPM 24 is continuously, for every FOV processed, receiving processed data from ISPM 49 , accumulating the results, and computing a score S i that reflects the probability of the specimen being abnormal. The score is transmitted to the CPM 24 on processed results line 46 . The decision logic in the CPM 24 is based on sets of thresholds that are determined during the system design and training phase.
The score S i , computed by Score Calculator 26 in CPM 24 for each decision point i, comprises part of the input to the control logic for determining whether to terminate slide processing. S i of decision point i is a computed score reflecting the probability of a specimen being abnormal. Each score S i is computed based on the accumulated information from the beginning of the slide processing up to the decision point i. At each i, a set of slide features F i1 . . . F in are computed. Each slide feature F ik is an accumulated algorithm processing output or a derivation from it. F ik are accumulated and derived by score calculator 26 , such as the accumulated number of cells classified as abnormal, and their average integrated optical density. The scoring functions G i can be any statistical classification method, such as decision tree, linear or non-linear mapping function, that applies combined high-dimensional slide features to generate a numeric value. In one embodiment, G i are Fisher's linear discriminant function. The features, as well as the scoring function G i used to compute each S i , could be different for each i. S i = G i ( F ) = G i ( F 11 , F 12 , ⋯ F i1 , F 21 , F 2 n , ⋯ F in )
The candidate feature set F i for computing S i comprises all accumulated slide features at all decision points j, 1<=j<=i. That is, F=[F jk , 1<=j<=i, 1<=k<=n]. A certain subset of features at each j, j<=i, may be chosen for computing S i because different features at different j, j<=i, may provide the best discriminating power for each type of abnormality found in the regular patient population. The use of two dimensional (2-D) features has the advantage of providing more discriminating power to separate the abnormal from the normal population. This is because the abnormal cell prevalence of different types of cells, such as squamous SIL, glandular atypical cells, etc., of abnormal slides varies. The false-positive alarm rate of each difference detection process step also varies. Each F jk contributes to discriminating different types of abnormal slides from normal slides. As a result, the discriminating power of different features, e.g., the number of classified abnormal squamous and glandular abnormal cells, can be optimal, in terms of signal to noise ratio, at different control points. This arises because only a limited number of certain types of abnormal cells, the signal, exist on each slide. The images acquired from these specimens were prioritized in terms of the probability of containing these type of cells. Thus, statistically, the signal to noise ratio actually deteriorates if more than the optimal number of images have been processed. 2-D Slide Features Control Point 1 F 11 , F 12 , F 13 … F i n 2 F 21 , F 22 … F 21 3 ⋮ ⋮ ⋮ i F i1 , F 12 , 1 … F 1 n n
The method and apparatus of the invention departs from the simple sequential random sampling methods of the prior art that assumes uniform probability and use.
Each feature set G i is determined based on the training data, slide population, collected up to decision point i. The criteria for designing G i is to optimize the decision so as to reject or accept slides as soon as possible and to obtain a best classification accuracy.
To dynamically sort out a biological specimen as requiring further human review or to indicate that no human review should be done is based on S i . There may be two sets of decision thresholds. One decision threshold set for the early rejection of the slides for human review: TR i for each decision point i. A second decision threshold set for the early acceptance of the slides as clearly normal, where no review is required: TA i for each decision point i.
By way of example and not limitation, in the application of prescreening cervical smears such as Pap smears for the detection of precursors and cancerous conditions, a prescreening system usually operates in a high sensitivity mode, which means a significant portion of normal specimens could be selected for human review resulting in a high ratio of false-positives. These false-positives may be the result of various conditions such as improper staining, inflammation, atrophic pattern, and the like. The system may not be able to dismiss the slides as normal no matter how many more images are sampled and processed. Since these false-positive slides require human review, rejecting them as early as possible saves unnecessary processing time and improves the system's overall throughput. A set of early rejection thresholds are used for this purpose. Whenever the score of a slide exceeds the early rejection threshold of that decision point (TR i <S i ), the CPM 24 will ask the ISPM 49 to terminate, and the specimen is selected for human review.
The early acceptance thresholds are used to accept clearly normal slides as no review. For cervical cancer prescreening this condition occurs when a sufficient number of images that have the highest likelihood of being abnormal among the specimen have been sampled and no evidence of abnormality is detected. That is, if the score of decision point i, S i is less than threshold TA i , then CPM 24 will ask ISPM 48 to terminate. The specimen is then sorted out as normal.
At any decision point i during processing, if neither condition is satisfied, i.e., TR i >S i >TA i , processing will continue until the slide is either rejected for review or accepted as clearly normal at a later decision point.
The TR i at each decision point i is designed to reject as many slides as possible requiring human review based on, for example, a fixed-1,000 image method, with the constraint of not rejecting the acceptable normal slides. The TA i is chosen to maximize the number of acceptable normal slides with the constraint of not falsely accepting the rejectable abnormal slides. While processing a specimen, as more images are scanned and processed, the computed score will gradually converge. Therefore, the difference between TR i and TA i gradually converges to 0.
As an example, the invention was tested at NeoPath, Inc., Redmond, Wash., where the invention effectively worked on a prescreening system that can sort out at least 50% of the normal population as no review and improved system throughput at least 20%. The test was based on a set of 4,543 slides. Each slide is sampled and processed up to 1,000 high-resolution images. While the images are scanned and processed, there is a slide score S i , 0<=S i <=1, computed at each decision point i, 1<=i<=10. A decision point i may be defined that corresponds to the point where 100×i images have been processed. An example set of TR i and TA i are defined as follows:
Decision
Point
TR i
TA i
1
1.0
0.0
2
1.0
0.0
3
0.3
0.0
4
0.3
0.0
5
0.3
0.0
6
0.3
0.0
7
0.3
0.085
8
0.28
0.095
9
0.2
0.099
10
0.1645
0.1645
The specimen diagnostic distribution is defined based on the regular patient population as follows for the purpose of performance estimation:
Diagnostic Category
Percentage
normal with edcx
85.5%
normal without edcx
9.5%
ASCUS/AGUS
3.9%
LSIL
0.8%
HSIL+
0.3%
The following chart shows the percentage of slides of each diagnostic category that are either rejected or accepted at each decision point. The accumulated results in terms of total rejection and acceptance rates is equivalent to only making the rejection/acceptance decision at the decision point 10, after having processed 1,000 images.
N w/
N w/
N w/o
N w/o
ASCUS
ASCUS
diag
edcx
edcx
edcx
edcx
/AGUS
/AGUS
LSIL
LSIL
HSIL+
HSIL+
decision
rejected
accepted
rejected
accepted
rejected
accepted
rejected
accepted
rejected
accepted
point
1
0
0
0
0
0
0
0
0
0
0
2
0
0
0
0
0
0
0
0
0
0
3
10.32
0
10.15
0
34.36
0
50.21
0
66.85
0
4
4.20
0
2.97
0
6.13
0
11.08
0
7.74
0
5
3.24
0
2.77
0
6.13
0
6.00
0
6.54
0
6
3.32
0
3.18
0
6.44
0
4.87
0
3.71
0
7
3.24
7.74
2.46
11.90
5.52
2.15
4.04
0.83
1.86
0.65
8
4.94
8.70
3.69
8.21
6.75
2.15
3.11
1.04
2.94
0.76
9
10.54
3.05
11.08
2.56
11.66
0.92
7.56
0.52
3.49
0.11
10
10.39
30.29
7.08
33.95
6.44
11.35
4.66
6.11
2.51
2.83
Total
50.22
49.78
43.38
56.62
83.43
16.57
91.50
8.50
95.65
4.35
For accuracy comparison, the following table lists the system performance of processing 1,000 fixed images per slide:
N w/
N w/
N w/o
N w/o
ASCUS
ASCUS
diag
edcx
edcx
edcx
edcx
/AGUS
/AGUS
LSIL
LSIL
HSIL+
HSIL+
By
rejected
accepted
rejected
accepted
rejected
accepted
rejected
accepted
rejected
accepted
1000
images
Total
50.12
49.88
43.90
56.10
82.82
17.18
91.41
8.59
95.65
4.37
Note that on average, slides rejected at decision point 3, 4, etc use only 30%, 40% . . . of the computation time for processing 1,000 images respectively. Therefore in total, early rejection mechanisms can save 15.7% of the computation time for normal with edcx slides, 14.1% for normal without edcx slides, 37.5% for ASCUS/AGUS slides, 49.3% for LSIL slides, and 57.7% for HSIL+slides. By using the regular patient population diagnosis distribution shown above to do the improvement projection, the early rejection mechanism can save up to 16.8% of the computation time. Similarly, the early acceptance mechanism can save 4.4% of the computation for N with edcx, 5.5% for N without edcx, 1.2% for ASCUS/AGUS slides, and 0.5% for LSIL slides. The total saving by early acceptance mechanism is 4.3% for the regular patient population.
The above estimation sums up to a total of 21.1% of computation saving by this score-thresholding based dynamic control and decision making DCDM mechanism, yet achieves the same level of accuracy as a system that processes 1,000 images for every slide.
The above example uses 1,000 as the maximum number of images to process per slide. To improve screener system sensitivity and accuracy, the number may be extended. That is, slides that can not be sorted out as either rejected or accepted will go on to scan and process more images as required. This dynamic method can help those abnormal slides that have low prevalence of abnormal material. Because this extended computation requirement only occurs for a small portion of the slides that are not sorted out yet, the impact on average slide processing time will be limited.
Refer now to FIG. 5 which shows the method of the invention to perform an image processing decision based on the result of an image feature extracted from the image. The image processing decision involves determining whether or not to perform an additional image processing module or step on the image. The process starts at step 302 , where the method of the invention acquires an image of the biological specimen. As stated herein, the biological specimen can be, for example, a Pap smear. In step 304 , the method of the invention performs feature extraction to extract features from the image of the biological specimen. In step 306 , the method of the invention chooses an image processing module, step or steps based on the feature extraction step 304 . Depending on the type of feature extracted in step 304 , a variety of processing modules will be executed. These image processing modules include: SIL, Edcx, intermediate cell, poly, bubble, image quality measurements and other image processing and object detection steps as described herein. The method of the invention now flows to step 308 to perform the additional image processing modules or steps.
FIGS. 2A and 2B show the method of the invention to dynamically control the sorting of biological specimens. In process block 102 , slide processing starts on an automated biological slide sorting apparatus. In one embodiment of the invention, slide processing is intended to sort the specimen into two categories; either not needing human review or needing human review. Those skilled in the art will appreciate that other slide processing procedures and slide sorting methods may benefit from the method of the invention.
In process step 104 , an initial prioritized scan sequence is determined and an initial set of processing steps are chosen to analyze the biological slide. The biological slide scans are prioritized according to a predetermined criteria. A low resolution scan determines the prioritized scan sequence based on the likelihoods of containing abnormals and endocervical cell groups in each image. The sequence is initialized as a balanced sequence as shown in FIG. 2 C. For each field of view the classifier will determine a Group score and a SIL score, shown on the x axis and y axis respectively. The group score indicates the likelihood of containing endocervical cell groups, Edcx, and the SIL score indicates the likelihood of containing abnormal cells. On the x axis, the group score is plotted from zero to ten where ten indicates that the field of view most likely contains a group. On the y axis, the SIL score is plotted from zero to ten where ten indicates that the field of view most likely contains an abnormal cell. The balanced scan sequence of FIG. 2C indicates that those fields of view that have a high group score and a high sil score are looked at first, as indicated by scan 261 . Those fields of view that have both a low SIL score and a low group score are looked at last, as indicated by scan 263 .
The following processes are initialized in the ISPM 49 :
SIL: for detecting abnormal squamous or glandular cells, and intermediate cells; and
GRP: for detecting normal Edcx cell groups.
In process block 106 each scan image is processed in sequence. In step 108 , a decision point is reached as to whether or not to continue computing slide features. If the number of images processed N>=t1 and n mode x=0, then N is a decision point, where t1 and x are predetermined constants. If slide features are to be processed, the method of the invention continues to step 112 to compute the 2D slide features. The 2D slide features are computed from all i images, t1<=i<=n. If slide features are not to be further processed the method of the invention steps to process step 120 .
In step 114 , the slide score S i is computed. In step 116 , a classification decision is reached based on the slide score. The decision reached is based on the Score S i :
if (S i >=R i ) then review;
if (S i <N i and # edcx group detected >Et ) then no review;
else no decision can be made yet; where R i , N i and Et are predetermined thresholds.
If a classification decision is made, the slide is sorted into review or no review at step 118 . If a decision is not reached on the score, the process flows to step 122 to determine if properties of the scan meet conditions for changing the scan sequence. If the properties of the scan meet these conditions, the remaining scan sequence is changed in step 124 . The scan sequence is changed if the number of endocervical groups detected is greater than Z t . If so, the sequence is changed to abnormal-cell major shown in FIG. 2 D. Fields of view with high SIL scores, shown by scan 265 , are checked first in order of group score. Fields of view with low SIL scores, shown by scan 267 , are checked last in order of group score. If the number of suspicious abnormal cells detected is greater than At, then the sequence is changed to Edcx-group major shown in FIG. 2E, where Z t , At are predetermined thresholds. Fields of view with high group scores, shown by scan 269 , are checked first in order of SIL score. Fields of view with low group scores, shown by scan 271 , are checked last in order of SIL score. Those skilled in the art will recognize that slide classification decisions based on other criteria and methods, other than slide scores, are within the spirit and scope of the invention.
In step 126 , the process checks to see if the result of scanning the specimen meets conditions for disabling a subset of processing steps. If the specimen does, the subset of processing steps are disabled in step 128 . If the number of endocervical groups detected is greater then Z t then the group detection process in the ISPM 49 is disabled. If the number of suspicious abnormal cells detected is greater than At, then the SIL detection process in the ISPM 49 is disabled. If the number of detected intermediate cells, for reference, is greater than I t , then the intermediate cell processing in ISPM 49 is disabled.
In step 130 , the method of the invention checks to see if conditions for enabling new processing steps are met. If the average number of detected small objects per image are greater than O t and i>t2, the number of images processed, then the inflammatory condition classifier steps are enabled in ISPM 49 , where t2 is a predetermined threshold. If the number of pixels in an image are saturated where the pixel value is equal to or greater than a maximum M t , then the air-bubble detection process is enabled in ISPM 49 , where M t is a predetermined threshold. If dark cell clumps are detected by segmentation, then the thick abnormal cell group classification process is enabled in the ISPM 49 . If any of the conditions are met, the method of the invention enables these processing steps in step 132 .
In step 134 , a check is made to determine if additional slide images remain in the scan sequence and are to be processed. If so, the method of the invention returns to step 106 to process the next slide image. The process then flows to step 136 to rescan and continue processing. If there are no more images available to scan and process, then the specimen can not yet be classified. The specimen is then rescanned and regions of interest are processed that contain detected potential abnormal cells. In step 138 the method of the invention computes the final slide score Si based on the slide feature information extracted from step 136 . The invention then sorts the slide for review or no review in step 140 and terminates in step 142 having potentially avoided unnecessary processing.
Refer now to FIG. 7 which shows the method of the invention to decide whether or not to continue image processing or perform an additional image processing step. The method starts in step 320 by acquiring an image of the biological specimen. In step 322 , a feature is extracted from the image. In step 324 , a check is made as to whether or not to continue image processing following the methods described herein. If the processing should continue, the process flows to step 326 to continue processing. Otherwise the method of the invention terminates image processing in step 328 .
Refer now to FIG. 8, which shows the method of the invention to decide whether to continue slide processing or perform an additional slide processing step. Slide processing is to be distinguished from image processing by the consideration of information from multiple images of the slide and from slide level information. For example, slide level decisions include whether to keep acquiring additional images from the slide, whether to change the type of images being acquired, or to change the steps used to process the images as described herein. The method of the invention starts in step 330 by acquiring an image of the biological specimen. In step 332 , a slide feature is extracted from the image. In step 334 , a check is made as to whether or not to continue slide processing following the methods described herein. If the slide processing is to continue, the process flows to step 338 to continue slide processing. If, in step 334 , the method of the invention decides not to continue slide processing, the process flows to step 336 to terminates slide processing.
Now refer to FIGS. 4A and 4B which show an alternate embodiment of the invention to dynamically control processing in an automated cytology analysis system. In one embodiment of the invention, the image analysis system 238 receives three control signals: the scan and process enable signal 201 , the scan and process next image signal 203 and the initialization signal 285 . The scan and process enable signal 201 and scan and process next image signal 203 are provided to the mechanical stage controller 212 . The mechanical stage controller also receives the x, y stage control signals 207 , 205 from the list of field of views that remain to be scanned and processed 204 or the list of field of views that contain detected and abnormal cells 210 .
The initialization signal 285 is provided to the initial sequencer 202 that performs a low-resolution abnormal and Edcx likelihood calculation and generates a sequence of field of views to scan. The calculation determines which fields of view that are most likely to contain abnormal and Edcx cells. A list of field of views that remain to be scanned 204 are output from the initial sequencer 202 . A field of view priority sequence reorder is done by a processor 208 . FOV priority sequence reorderer 208 changes the FOV priority sequence in response to change sequence mode control line 209 . In one embodiment, the processor 208 can be a microprocessor. Processor 208 reorders the field of views based on a selected criteria, such as the method described in assignee's U.S. Pat. No. 5,757,954, issued May 26, 1998 to Kuan et al., entitled “Field Prioritization Apparatus and Method”. The microscope stage is moved by mechanical stage controller 212 to the x, y position of the field of view. The image focusing and image acquisition system 214 provides an image 216 of the field of view. This image is then provided to a number of sub processors that perform a range of image processing tasks. The control process module, CPM 24 , enables or disables each of these subprocesses by control line 218 . Each sub process provides processing results 232 to the control process module on results output 234 .
In the Sil and glandular abnormal detection subprocess 220 , the image 216 is processed to detect abnormal cells that are likely to be Sil and glandular abnormal. This processing is described in more detail in applicant's U.S. Pat. No. 5,978,497, issued Nov. 2, 1999, to Lee et al., entitled “APPARATUS FOR THE IDENTIFICATION OF FREE-LYING CELLS”; U.S. Pat. No. 5,978,498, issued Nov. 2, 1999 to Wilhelm et al., entitled “APPARATUS FOR AUTOMATED IDENTIFIC ATION OF CELL GROUPINGS ON A BIOLOGICAL SPECIMEN” which is a file wrapper continuation of abandoned U.S. patent application Ser. No. 08/309,061; and U.S. Pat. No. 5,987,158, issued Nov. 16, 1999 to Meyer et al. Entitled “APPARATUS FOR AUTOMATED IDENTIFICATION OF THICK CELL GROUPINGS ON A BIOLOGICAL SPECIMEN” which is a file wrapper continuation of abandoned U.S. patent application Ser. No. 08/309,116.
In the Edcx group detection subprocess 222 , the image 216 is processed to detect Edcx groups. This processing is also described in more detail in the above referenced applications.
In the intermediate cell detection subprocess 224 , the image 216 is processed to detect intermediate cells. The processing is also described in more detail in the above referenced applications.
In the poly detection subprocess 226 , the image 216 is processed to detect poly cells. This processing is also described in more detail in the above referenced applications.
In the bubble detection subprocess 228 , the image 216 is processed to detect bubbles in the coverslip adhesive. This processing is described in more detail in applicant's U.S. Pat. No. 5,566,249, issued Oct. 15, 1996 to Rosenlof et al., entitled “APPARATUS FOR DETECTING BUBBLES IN COVERSLIP ADHESIVE”.
In the image quality measurement subprocess 230 , the image is processed to measure the image's quality. If the image is saturated, then there may be an air bubble.
Those skilled in the art will recognize that the invention can control other image processing operations other than the ones shown. By avoiding various subprocessing steps the time required to analyze and rescan the fields of view is reduced.
The invention generates another list of fields of view that contain detected abnormal cells 210 . This list is used as an input to the mechanical stage mover 212 . The image analysis system proceeds to rescan each one of these fields of view.
The results output 234 contains information about the field of view such as the number of objects that are squamous, glandular or a member of a cell group, the number of cells detected that have a likelihood of abnormality and the associated confidence of the likelihood, the number of normal intermediate cells detected, the features of the normal cells detected, the number of squamous cells detected, the number of small objects detected and the number of pixels that are saturated.
Refer now to FIG. 6 which shows the method of the invention to decide whether or not to acquire another image of the biological specimen. The method starts in step 310 where an image of the biological specimen is acquired. The process then flows to step 312 to extract a feature from the image of the biological specimen. The process then flows to step 314 to check whether or not a classification decision can be made. If a classification decision can be made, the method of the invention flows to step 315 to make the classification decision based on the currently acquired image. If a classification decision can not be made then the method acquires an additional image in step 317 . The process then flows to step 316 to choose an additional image processing step. In step 318 , the additional image processing step is performed on the newly acquired image. The additional image processing module chosen in step 316 is similar to the additional image processing modules referenced in FIGS. 4A, 4 B and 5 as well as additional image processing modules.
Refer now to FIG. 9, which shows the method of the invention to rescan and process certain areas using different image processing steps. The method starts with step 340 to scan and process images based on a current prioritized scan sequence. If a classification decision can be made in step 342 , the process flows to step 344 to make the slide classification decision and terminate slide processing. If a classification decision can not be made in step 342 , then the method of the invention flows to step 343 to determine whether or not to change the current prioritized image scan sequence. If the current prioritized image scan sequence is not to be changed, the process flows to step 341 to follow the current sequence, otherwise the process flows to step 346 where the current prioritized image scan sequence is changed to a new prioritized scan sequence. The process then flows to step 347 to determine whether a subset of image processing steps should be disabled. If so, the method of the invention disables a subset of image processing steps in step 348 , otherwise the existing image processing steps are used in step 345 . The process then flows to step 349 to check if additional image processing steps should be enabled. If so, the method of the invention enables a new set of image processing steps in step 350 , otherwise the current processing steps are used in step 351 . In step 352 , the method of the invention rescans and processes areas using the current image processing steps.
In a presently preferred embodiment of the invention, the system disclosed herein is used in a system for analyzing cervical pap smears, such as that shown and disclosed in U.S. Pat. No. 5,787,188, issued Jul. 28, 1998 to Nelson et al., entitled “METHOD FOR IDENTIFYING NORMAL BIOMEDICAL SPECIMENS”, which is a file wrapper continuation of abandoned U.S. patent application Ser. No. 07/838,064, filed Feb. 18, 1992; U.S. Pat. No. 5,528,703, issued Jun. 18, 1996 to Lee et al., entitled “METHOD FOR IDENTIFYING OBJECTS USING DATA PROCESSING TECHNIQUES” which is a file wrapper continuation of abandoned U.S. patent application Ser. No. 07/838,395, filed Feb. 18, 1992; U.S. Pat. No. 5,315,700, issued May 24, 1994 to Johnston et al., entitled “METHOD AND APPARATUS FOR RAPIDLY PROCESSING DATA SEQUENCES”; U.S. Pat. No. 5,361,140, issued Nov. 1, 1994 to Hayenga et al., entitled “METHOD AND APPARATUS FOR DYNAMIC CORRECTION OF MICROSCOPIC IMAGE SIGNALS”; and U.S. Pat. No. 5,912,699, issued Jun. 15, 1999 to Hayenga et al., entitled “METHOD AND APPARATUS FOR RAPID CAPTURE OF FOCUSED MICROSCOPIC IMAGES” which is a continuation-in-part of abandoned U.S. patent application Ser. No. 07/838,063, filed Feb. 18, 1992, the disclosures of which are incorporated herein, in their entirety, by the foregoing references thereto.
Now refer to FIGS. 3A, 3 B and 3 C which show a schematic diagram of one embodiment of the apparatus of the invention for dynamic control of slide processing 500 . The apparatus of the invention comprises an imaging system 502 , a motion control system 504 , an image processing system 536 , a central processing system 540 , and a workstation 542 . The imaging system 502 is comprised of an illuminator 508 , imaging optics 510 , a CCD camera 512 , an illumination sensor 514 and an image capture and focus system 516 . The image capture and focus system 516 provides video timing data to the CCD cameras 512 , the CCD cameras 512 provide images comprising scan lines to the image capture and focus system 516 . An illumination sensor intensity is provided to the image capture and focus system 516 where an illumination sensor 514 receives the sample of the image from the optics 510 . In some embodiments, optics 510 may comprise color filters. In one embodiment of the invention, the optics may further comprise an automated microscope 511 . The illuminator 508 provides illumination of a slide. The image capture and focus system 516 provides data to a VME bus 538 . The VME bus distributes the data to an image processing system 536 . The image processing system 536 is comprised of field-of-view processors 568 . The images are sent along the image bus 564 from the image capture and focus system 516 . A central processor 540 controls the operation of the invention through the VME bus 538 . In one embodiment, the central processor 562 comprises a MOTOROLA 68030 CPU. The motion controller 504 is comprised of a tray handler 518 , a microscope stage controller 520 , a microscope tray controller 522 , and a calibration slide 524 . The motor drivers 526 position the slide under the optics. A bar code reader 528 reads a barcode located on the slide 524 . A touch sensor 530 determines whether a slide is under the microscope objectives, and a door interlock 532 prevents operation in case the doors are open. Motion controller 534 controls the motor drivers 526 in response to the central processor 540 . An Ethernet communication system 560 communicates to a workstation 542 to provide control of the system. A hard disk 544 is controlled by workstation 550 . In one embodiment, workstation 550 may comprise a workstation. A tape drive 546 is connected to the workstation 550 as well as a modem 548 , a monitor 552 , a keyboard 554 , and a mouse pointing device 556 . A printer 558 is connected to the ethernet 560 .
During operation, the central computer 540 , running an operating system, controls the microscope 511 and the processor to acquire and digitize images from the microscope 511 . The flatness of the slide may be checked, for example, by contacting the four corners of the slide using a computer controlled touch sensor. The computer 540 also controls the microscope 511 stage to position the specimen under the microscope objective, and from one to fifteen field of view (FOV) processors 568 which receive images under control of the computer 540 .
It is to be understood that the various processes described herein may be implemented in software suitable for running on a digital processor. The software may be embedded, for example, in the central processor 540 .
The present invention is also related to biological and cytological systems as described in the following patent applications which are assigned to the same assignee as the present invention, filed on Sep. 20, 1994 (unless otherwise noted), and which are all hereby incorporated by reference including U.S. Pat. No. 5,757,954, issued May 26, 1998 to Kuan et al entitled, “FIELD PRIORITIZATION APPARATUS AND METHOD”; U.S. Pat. No. 5,978,498, issued Nov. 2, 1999 to Wilhelm et al., entitled “APPARATUS FOR AUTOMATED IDENTIFICATION OF CELL GROUPINGS ON A BIOLOGICAL SPECIMEN” which is a file wrapper continuation of abandoned U.S. patent application Ser. No. 08/309,061; U.S. Pat. No. 5,987,158, issued Nov. 16, 1999 to Meyer et al., entitled “APPARATUS FOR AUTOMATED IDENTIFICATION OF THICK CELI GROUPINGS ON A BIOLOGICAL SPECIMEN”, which is a file wrapper continuation of abandoned U.S. patent application Ser. No. 08/309,116; U.S. Pat. No. 5,787,189, issued Jul. 28, 1998 to Lee et al. entitled “BIOLOGICAL ANALYSIS SYSTEM SELF CALIBRATION APPARATUS”, which is a file wrapper continuation of abandoned U.S. patent application Ser. No. 08/309,115; U.S. Pat. No. 5,828,776, issued Oct. 27, 1998 to Lee et al. entitled “APPARATUS FOR IDENTIFICATION AND INTEGRATION OF MULTIPLE CELL PATTERNS”, which is a file wrapper continuation of abandoned U.S. patent application Ser. No. 08/308,992; U.S. Pat. No. 5,627,908, issued May 6, 1997 to Lee et al. entitled “METHOD FOR CYTOLOGICAI, SYSTEM DYNAMIC NORMALIZATION”; U.S. Pat. No. 5,638,459, issued Jun. 10, 1997 to Rosenlof et al. entitled “METHOD AND APPARATUS FOR DETECTING A MICROSCOPE SLIDE COVERSLIP”; U.S. Pat. No. 5,566,249, issued Oct. 15, 1996 to Rosenlof et al. entitled “APPARATUS FOR DETECTING BUBBLES IN COVERSLIP ADHIESIVE”; U.S. Pat. No. 5,933,519, issued Aug. 3, 1999, to Lee et al. entitled “CYTOLOGICAL SLIDE SCORING APPARATUS” which is a file wrapper continuation of abandoned U.S. patent application Ser. No. 08/309,931; U.S. Pat. No. 5,692,066, issued Nov. 25, 1997 to Lee et al. entitled “METHOD AND APPARATUS FOR IMAGE PLANE MODULATION PATTERN RECOGNITION”; U.S. Pat. No. 5,978,497, issued Nov. 2, 1999, to Lee et al. entitled “APPARATUS FOR THE IDENTIFICATION OF FREE-LYING CELLS”; U.S. Pat. No. 5,715,327, issued Feb. 3, 1998 to Wilhelm et al., entitled “METHOD AND APPARATUS FOR DETECTION OF UNSUITABLE CONDITIONS FOR AUTOMATED CYTOLOGY SCORING”; U.S. Pat. No. 5,647,025, issued Jul. 8, 1997 to Frost et al., entitled “AUTOMATIC FOCUSING OF BIOMEDICAL SPECIMENS APPARATUS”; U.S. Pat. No. 5,677,762, issued Oct. 14, 1997 to Ortyn et al., entitled “APPARATUS FOR ILLUMINATION STABILIZATION AND HOMOGENIZATION”, which is a file wrapper continuation of abandoned U.S. patent application Ser. No. 08/309,064; U.S. Pat. No. 5,875,258, issued Feb. 23, 1999 to Ortyn et al, entitled “BIOLOGICAL SPECIMEN ANALYSIS SYSTEM PROCESSING INTEGRITY CHECKING APPARATUS”, which is a file wrapper continuation of abandoned U.S. patent application Ser. No. 08/309,249; U.S. Pat. No. 5,581,631, issued Dec. 3, 1996 to Ortyn et al., entitled “CYTOLOGICAL SYSTEM IMAGE COLLECTION INTEGRITY CHECKING APPARATUS”; U.S. Pat. No. 5,557,097, issued Sep. 17, 1996 to Ortyn et al., entitled “CYTOLOGICAL SYSTEM AUTOFOCUS INTEGRITY CHECKING APPARATUS”; U.S. Pat. No. 5,787,189, issued Jul. 28, 1998 to Lee et al., entitled “BIOLOGICAL ANALYSIS SYSTEM SELF CALIBRATION APPARATUS”, which is a file wrapper continuation of abandoned U.S. patent application Ser. No. 08/309,115; U.S. Pat. No. 5,740,269, issued Apr. 14, 1998 to Oh et al., entitled “A METHOD AND APPARATUS FOR ROBUST BIOLOGICAL SPECIMEN CLASSIFICATION”; U.S. Pat. No. 5,797,130, issued Aug. 18, 1998 to Nelson et al., entitled “METHOD FOR TESTING PROFICIENCY IN SCREENING IMAGES OF BIOLOGICAL SLIDES” which is a file wrapper continuation of abandoned U.S. patent application Ser. No. 08/153,293 filed Nov. 16, 1993; pending U.S. patent application Ser. No. 08/485,182 to Lee et al., filed Jun. 7, 1995, entitled “INTERACTIVE METHOD AND APPARATUS FOR SORTING BIOLOGICAL SPECIMENS”; U.S. Pat. No. 5,715,326, issued Feb. 3, 1998 Ortyn et al., entitled “CYTOLOGICAL SYSTEM ILLUMINATION INTEGRITY CHECKING APPARATUS AND METHOD”; U.S. Pat. No. 5,499,097, issued Mar. 12, 1996 to Ortyn et al., entitled “METHOD AND APPARATUS FOR CHECKING AUTOMATED OPTICAL SYSTEM PERFORMANCE REPEATABILITY”; U.S. Pat. No. 5,799,101, issued Aug. 25, 1998 to Lee et al., entitled “METHOD AND APPARATUS FOR HIGHLY EFFICIENT COMPUTER AIDED SCREENING”, which is a file wrapper continuation of abandoned U.S. patent application Ser. No. 08/315,719, filed Sep. 30, 1994; U.S. Pat. No. 5,787,208, issued Jul. 28, 1998 to Oh et al., entitled “IMAGE ENHANCEMENT METHOD AND APPARATUS”; U.S. Pat. No. 5,625,706, issued Apr. 29, 1997 to Lee et al., entitled “METHOD AND APPARATUS FOR CONTINUOUSLY MONITORING AND FORFCASTING SLIDE AND SPECIMEN PREPARATION FOR A BIOLOGICAL SPE EIMEN POPULATION”; U.S. Pat. No. 5,745,601, issued Apr. 28, 1998 to Lee et al., entitled “ROBUSTNESS OF CLASSIFICATION MEASUREMENT APPARATUS AND METHOD”; U.S. Pat. No. 5,671,288, issued Sep. 23, 1997 to Wilhelm et al., entitled “METHOD AND APPARATUS FOR ASSESSING SLIDE AND SPECIMEN PREPARATION QUALITY”; U.S. Pat. No. 5,621,519, issued Apr. 15, 1997 to Frost et al., entitled “IMAGING SYSTEM TRANSFER FUCNCTIO CONTROL METHOD AND APPARATUS”; U.S. Pat. No. 5,619,428, issued Apr. 8, 1997 to Lee et al., entitled “METHOD AND APPARATUS FOR INTEGRATING AN AUTOMATED SYSTEM TO A LABORATORY”; U.S. Pat. No. 5,781,667, issued Jul. 14, 1998 to Schimidt et al., entitled “APPARATUS FOR HIGH SPEED MORPHOLOGICAL PROCESSING” and U.S. Pat. No. 5,642,433, issued Jun. 24, 1997 to Lee et al, entitled “METHOD AND APPARATUS FOR IMAGE CONTRAST QUALITY EVALUATION”.
The invention has been described herein in considerable detail in order to comply with the Patent Statutes and to provide those skilled in the art with the information needed to apply the novel principles and to construct and use such specialized components as are required. However, it is to be understood that the invention can be carried out by specifically different equipment and devices, and that various modifications, both as to the equipment details and operating procedures, can be accomplished without departing from the scope of the invention itself. | Dynamic control of the processing flow of an image analyzer such as a biological specimen analyzer as processing proceeds. Data collected and processed from a specimen under analysis, such as a biological specimen on a microscope slide, determines the fate of further processing. If there is enough evidence, based on the data collected from a slide, to make a decision with sufficient confidence, the processing of the slide can be stopped and a decision may be rendered. By avoiding unnecessary additional computation system throughput may be enhanced. Otherwise, data collection and computation continues until either certain termination criteria are met or no more data is left to acquire. This slide-dependent control and decision making method flexibly limits the amount of computation required to reach a system decision about a specimen. By evaluating analysis processing continuously a maximum signal to noise ratio may be achieved by preventing additional noise from entering the analysis and thus swamping signal information. | 8 |
RIGHTS OF THE GOVERNMENT
The invention described herein may be manufactured and used by or for the Government of the United States for all governmental purposes without the payment of any royalty.
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is related to U.S. patent application Ser. No. 13/025,624, filed on even date herewith by Pinkus et al., and entitled “Automatic Landolt C Gap Detection Software Architecture for Image Quality Analysis” (AFD 1121), the disclosure of which is incorporated by reference herein in its entirety.
BACKGROUND OF THE INVENTION
The present invention relates to pattern and object recognition, and more particularly to a method for detecting an object in a digital image.
Over the years, there have been many methods developed to determine the image quality of an image-generating system such as a sensor/display combination. In most cases, the final consumer of the image produced is a human observer using their visual capability to extract visual information from the displayed image. In recent years, imaging systems and image manipulation have moved from the analog world to the digital world, which has probably added a bit more confusion to the issue of image quality or resolution.
In general, resolution is the ability of a sensor/display system to produce detail; the higher the resolution, the finer the detail that can be displayed. With the advent of digital imagery and sensor detectors that are composed of an array of discrete elements, it is tempting, and not entirely wrong, to characterize the resolution of the system by the number of picture elements (pixels) for the display or sensor elements in the case of the sensor. For example, VGA resolution for a computer display is 480 elements high by 640 elements wide and SVGA is 600×800 elements. This describes the number of samples that can be displayed; however, the number of pixels alone says nothing of the quality of the actual display medium characteristics (luminance, contrast capability, noise, color, refresh rate, active area to total area ratio, etc.) or of the signal/information used to feed the individual pixels. Nevertheless, this numerical value of pixel or sensor element count is often given as a primary metric to the resolution (quality) of the sensor or display.
Another common approach to determining the resolution of a sensor/display system is to image an appropriate resolution test target and determine the smallest sized critical test pattern element that can be seen by a human observer. Many test patterns have been developed over the years such as grating, tri-bars, tumbling Es, the Snellen chart, and the Landolt C chart to test vision or to test imaging systems using vision. The test pattern typically has test elements of various sizes so that the human observer can pick out the smallest size that they can resolve. An alternative to the multi-sized test pattern is to use a single size test element, but image it at various distances until a distance is obtained at which the test object is barely resolved.
Related to resolution is visual acuity, which is acuteness or clearness of vision that is dependent on the sharpness of the retinal focus within the eye and the sensitivity of the interpretative faculty of the brain. For example, numerous methods have been used to determine night vision goggle (“NVG”) visual acuity such as limiting resolution, Snellen Acuity, square wave targets, Landolt Cs, adaptive psychophysical, and directly measuring the psychometric function or the “frequency of seeing” curve. Each method produces a number that is composed of an actual acuity value plus error. There can be many sources of error but the largest is generally the method itself as well as the inherent variability of the observer while working under threshold conditions. Observer variability may be reduced through extensive training, testing the same time every day, and shortened sessions in order to reduce eye fatigue. Additionally, even though observers are given specific instructions, response criteria may also vary among or within observers; even over the course of a single experimental session. To assist in eliminating the criteria problem, a four alternative forced-choice paradigm was developed and utilized to measure the entire psychometric function. This paradigm allowed for any desired response criteria level (e.g., 50% or 75% corrected for chance, probability of detection) to be selected for the prediction of (NVG) visual acuity performance. Although all of the preceding was directed at visual acuity/resolution assessment of night vision goggles using multiple human observers the “resolution” concept applies equally well to digital imagery.
Current and future military weapons systems (e.g. micro UAVs, satellites, surveillance, weapons aiming optics, day/night head-mounted devices) will increasingly rely on digitally-based multi-spectral imaging capabilities. With digital media comes the potential to register, fuse, and enhance digital images whether they are individual images or streaming video gathered in real-time. Multi-spectral fusion and enhancement provides the greatly increased potential to detect, track, and identify difficult targets, such as those that are camouflaged, buried, hidden behind a smoke screen or obscured by atmospheric effects (haze, rain, fog, snow).
There are several different conventional techniques to assess the relative improvement in image quality when an image-enhancing algorithm has been applied to a digital image. The testing of enhancing effects often consists of subjective quality assessments or measures of the ability of an automatic target detection program to find a target before and after an image has been enhanced. It is rare to find studies that focus on the human ability to detect a target in an enhanced image using scenarios that are relevant for the particular application for which the enhancement is intended. While a particular algorithm may make an image appear substantially better after enhancement, there is no indication as to whether this improvement is significant enough to improve human visual performance.
Therefore, there is a need in the art to automatically assess image quality in terms of modeled human visual resolution perceptual qualities (i.e., the “frequency of seeing” curve) but without the need to actually use human observers.
SUMMARY OF THE INVENTION
Embodiments of the invention address the need in the art by providing a method of detecting a target image, and in particular a triangle having a particular orientation. A plurality of ring contour images is created by blurring the image, posterizing the blurred image at a plurality of levels to generate a plurality of posterized images, and creating the plurality of ring contour images from each of the plurality of posterized images. Additionally, a plurality of convex hull images is created by creating a plurality of corner images from corners within the image located by at least two different corner algorithms, finding a bounding rectangle that encompasses the plurality of ring contour images, cropping the plurality of corner images using the bounding rectangle, applying a threshold to the plurality of cropped corner images, and creating the plurality of convex hull images by generating a convex hull from the corners in each of the plurality of cropped corner images. From these sets of images a plurality of triangles is created by fitting a triangle with an orientation to each of the plurality of ring contour images and each of the plurality of convex hull images. Finally, the orientation of the triangle is determined from the plurality of triangles.
In some embodiments, and prior to creating the plurality of ring contour images and the plurality of convex hull images, the image may be prepared by first enlarging the image. The enlarged image may then be cropped to a target area of interest in the image to assist in reducing computation and processing times. The cropped image is then denoised and sharpened utilizing standard denoise and sharpening algorithms as known in the art.
In some embodiments, the plurality of ring contour images is created from each of the plurality of posterized images. The approximate center of the blurred image is determined. A start point is located on a color boundary. The color boundary is then traversed from the start point to generate a contour. If the traversal of the color boundary ends on the start point and if the resulting contour encloses the approximate center of the blurred image, a ring contour image is created including the contour.
In some embodiments, triangles are fit to each of the plurality of ring contour images and each of the plurality of convex hull images by first retrieving a contour from an image of the plurality of contour images or a convex hull from an image of the plurality of convex hull images. A triangle in a first orientation is fit to the contour or convex hull. If the triangle in the first orientation does not encompass the contour or convex hull, the triangle in the first orientation is enlarged until it does encompass the contour or convex hull. A triangle in a second orientation is also fit to the contour or convex hull. Similarly, if the triangle in the second orientation does not encompass the contour or convex hull, the triangle in the second orientation is enlarged until it does encompass the contour or convex hull. In some embodiments, additional orientations of triangles may be fitted to the contour and complex hull. Finally, the smaller of the triangles fit to the contour or convex hull is selected.
In some embodiments, the orientations of the triangles may include the triangle being oriented in an upward direction, a downward direction, a rightward direction, a leftward direction, and combinations thereof. In a specific embodiment, the orientation of the triangle is determined from the plurality of triangles by selecting an orientation corresponding to a majority of the plurality of triangles.
Embodiments of the invention also provide an apparatus having a processor and program code. The program code is configured to be executed by the processor to detect an image. The program code is further configured to create a plurality of ring contour images by blurring the image, posterizing the blurred image at a plurality of levels to generate a plurality of posterized images, and creating the plurality of ring contour images from each of the plurality of posterized images. The program code is further configured to create a plurality of convex hull images by creating a plurality of corner images from corners within the image located by at least two different corner algorithms, finding a bounding rectangle that encompasses the plurality of ring contour images, cropping the plurality of corner images using the bounding rectangle, applying a threshold to the plurality of cropped corner images, and creating the plurality of convex hull images by generating a convex hull from the corners in each of the plurality of cropped corner images. The program code is further configured to create a plurality of triangles by fitting a triangle with an orientation to each of the plurality of ring contour images and each of the plurality of convex hull images. And finally the program code is further configured to determine the orientation of the triangle from the plurality of triangles.
Embodiments of the invention additionally provide a program product including a computer recordable type medium and a program code configured to detect an image. The program code is resident on the computer recordable type medium and further configured, when executed on a hardware implemented processor, to create a plurality of ring contour images by blurring the image, posterizing the blurred image at a plurality of levels to generate a plurality of posterized images, and creating the plurality of ring contour images from each of the plurality of posterized images. The program code is further configured to create a plurality of convex hull images by creating a plurality of corner images from corners within the image located by at least two different corner algorithms, finding a bounding rectangle that encompasses the plurality of ring contour images, cropping the plurality of corner images using the bounding rectangle, applying a threshold to the plurality of cropped corner images, and creating the plurality of convex hull images by generating a convex hull from the corners in each of the plurality of cropped corner images. The program code is further configured to create a plurality of triangles by fitting a triangle with an orientation to each of the plurality of ring contour images and each of the plurality of convex hull images. And finally the program code is further configured to determine the orientation of the triangle from the plurality of triangles.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with a general description of the invention given above, and the detailed description given below, serve to explain the invention.
FIG. 1 is a schematic block diagram of an exemplary hardware and software environment for a computer system suitable for implementing an algorithm to detect images consistent with embodiments of the invention.
FIG. 2 illustrates a target image to be recognized at a distance from an observer or sensor to be used with the image detection algorithm.
FIG. 3 is a flow chart illustrating the steps to prepare an image for the image detection algorithm.
FIG. 4 is a flow chart illustrating a portion of the image detection algorithm.
FIG. 5 is a flow chart illustrating a portion of the image detection algorithm.
FIG. 6 is a flow chart illustrating a portion of the image detection algorithm.
FIG. 7 is a flow chart illustrating a portion of the image detection algorithm.
FIG. 8 is a flow chart illustrating a portion of the image detection algorithm.
FIG. 9 is a flow chart illustrating a portion of the image detection algorithm.
FIG. 10 illustrates a set of exemplary results from the image detection algorithm used to select the final image orientation.
FIG. 11 is a table representing results from images acquired from various sensors at various distances.
FIG. 12 is a graph of the data in the table in FIG. 11 .
It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various features illustrative of the basic principles of the invention. The specific design features of the sequence of operations as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes of various illustrated components, will be determined in part by the particular intended application and use environment. Certain features of the illustrated embodiments have been enlarged or distorted relative to others to facilitate visualization and clear understanding. In particular, thin features may be thickened, for example, for clarity or illustration.
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the invention address the need in the art by providing a software architecture and procedure that allow automatic detection of digital images and quality using only a computer. This is in contrast to either simple “before” and “after” subjective visual comparisons or laborious and costly psychophysical procedures requiring extensive testing of multiple trained observers who are required to view and correctly judge the different orientation of many differently sized stimuli such as Landolt Cs or triangles. Embodiments of the invention utilize a software-implemented automatic Triangle Orientation Detection (“TOD”) model, which has been designed to produce a similar frequency of seeing function as those produced by real observers. Thus, the variations among different multispectral sensors as well as image registration, fusion, and/or enhancement algorithms can be relatively quickly, accurately, and automatically assessed in terms of human visual perception but without the need for human observers.
Turning to the drawings, wherein like numbers denote like parts throughout the several views, FIG. 1 illustrates an exemplary hardware and software environment for an apparatus 10 suitable for implementing an image quality assessment system consistent with embodiments of the invention. For the purposes of the invention, apparatus 10 may represent practically any type of computer, computer system or other programmable electronic device, including a client computer, a server computer, a portable computer, a handheld computer, an embedded controller, etc. Moreover, apparatus 10 may be implemented using one or more networked computers, e.g., in a cluster or other distributed computing system. Apparatus 10 will hereinafter also be referred to as a “computer,” although it should be appreciated that the term “apparatus” may also include other suitable programmable electronic devices consistent with embodiments of the invention.
Computer 10 typically includes a central processing unit (CPU) 12 including one or more microprocessors coupled to a memory 14 , which may represent the random access memory (RAM) devices comprising the main storage of computer 10 , as well as any supplemental levels of memory, e.g., cache memories, non-volatile or backup memories (e.g., programmable or flash memories), read-only memories, etc. In addition, memory 14 may be considered to include memory storage physically located elsewhere in computer 10 , e.g., any cache memory in a processor in CPU 12 , as well as any storage capacity used as a virtual memory, e.g., as stored on a mass storage device 16 or on another computer coupled to computer 10 .
Computer 10 also typically receives a number of inputs and outputs for communicating information externally. For interface with a user or operator, computer 10 typically includes a user interface 18 incorporating one or more user input devices 20 (e.g., a keyboard, a mouse, a trackball, a joystick, a touchpad, and/or a microphone, among others) and a display 22 (e.g., a CRT monitor, an LCD display panel, and/or a speaker, among others). Otherwise, user input may be received via another computer or terminal, e.g., via a client or single-user computer (not shown) coupled to computer 10 over a network 24 . This latter implementation may be desirable where computer 10 is implemented as a server or other form of multi-user computer. However, it should be appreciated that computer 10 may also be implemented as a standalone workstation, desktop, laptop, hand-held, or other single-user computer in some embodiments.
For non-volatile storage, computer 10 typically includes one or more mass storage devices 16 , e.g., a floppy or other removable disk drive, a hard disk drive, a direct access storage device (DASD), an optical drive (e.g., a CD drive, a DVD drive, etc.), flash memory data storage devices (USB flash drive) and/or a tape drive, among others. Furthermore, computer 10 may also include an interface 26 with one or more networks 24 (e.g., a LAN, a WAN, a wireless network, and/or the Internet, among others) to permit the communication of information with other computers and electronic devices. It should be appreciated that computer 10 typically includes suitable analog and/or digital interfaces (e.g., BUS) between CPU 12 and each of components 14 , 16 , 18 , and 26 , as is well known in the art.
Computer 10 operates under the control of an operating system 28 , and executes or otherwise relies upon various computer software applications, components, programs, objects, modules, data structures, etc. For example, an image detection algorithm 30 may be resident in memory 14 to analyze image 32 also in memory or alternately resident in mass storage 16 . Moreover, various applications, components, programs, objects, modules, etc. may also execute on one or more processors in another computer coupled to computer 10 via the network 24 , e.g., in a distributed or client-server computing environment, whereby the processing required to implement the functions of a computer program, such as the image detection algorithm 30 , may be allocated to multiple computers over the network 24 .
In general, the routines executed to implement the embodiments of the invention, whether implemented as part of an operating system or a specific application, component, program, object, module or sequence of instructions, or even a subset thereof, will be referred to herein as “computer program code,” or simply “program code.” Program code typically comprises one or more instructions that are resident at various times in various memory and storage devices in a computer, and that, when read and executed by one or more processors in a computer, cause that computer to perform the steps necessary to execute steps or elements embodying the various aspects of the invention. Moreover, while the invention has and hereinafter will be described in the context of fully functioning computers and computer systems, those skilled in the art will appreciate that the various embodiments of the invention are capable of being distributed as a program product in a variety of forms, and that the invention applies equally regardless of the particular type of computer readable signal bearing media used to actually carry out the distribution. Examples of computer readable media include but are not limited to recordable type media such as volatile and non-volatile memory devices, floppy and other removable disks, hard disk drives, magnetic tape, optical disks (e.g., CD-ROMs, DVDs, etc.), among others.
In addition, various program code described hereinafter may be identified based upon the application within which it is implemented in a specific embodiment of the invention. However, it should be appreciated that any particular program nomenclature that follows is used merely for convenience, and thus the invention should not be limited to use solely in any specific application identified and/or implied by such nomenclature. Furthermore, given the typically endless number of manners in which computer programs may be organized into routines, procedures, methods, modules, objects, and the like, as well as the various manners in which program functionality may be allocated among various software layers that are resident within a typical computer (e.g., operating systems, libraries, API's, applications, applets, etc.), it should be appreciated that the invention is not limited to the specific organization and allocation of program functionality described herein.
Those skilled in the art will recognize that the exemplary environment illustrated in FIG. 1 is not intended to limit the present invention. Indeed, those skilled in the art will recognize that other alternative hardware and/or software environments may be used without departing from the scope of the invention.
Embodiments of the invention implement an algorithm 30 configured to detect Triangles as a resolution target. As illustrated in FIG. 2 , a sensor, such as an Infrared (IR), Near Infrared (NIR), or Visual (VIS) sensor, 34 is directed at a target 36 . Images 32 of the target 36 were acquired at multiple distances 38 from the sensor 34 to the target 36 as the method for probing the resolution of the sensor. As discussed above and in an alternate embodiment, the size of the Target 36 may also be adjusted, holding the distance 38 constant. Each of the images 32 is prepared as seen in the flowchart 40 in FIG. 3 , prior to being analyzed. Turning now to FIG. 3 , the process starts at block 42 . The image is first enlarged at block 44 , with the factor of enlargement being dependent on the sensor. For example, in a specific embodiment, the image 32 is enlarged by a factor of four. After the image is enlarged, the image is cropped around an area of interest at block 46 to assist in reducing the amount of computation time necessary to analyze the image. In a specific embodiment with a sensor having a resolution of 640×480, the image may be cropped to a size of 180×120, which is sufficient to encompass the target 36 . The image is then sent through a denoising algorithm (block 48 ) and a sharpening algorithm (block 50 ). Any standard denoise and sharpen algorithm as are known to those of ordinary skill in the art may be used for blocks 48 ad 50 . The process ends at block 52 .
The algorithm associated with embodiments of the invention then uses two different methods to identify and locate the target 36 in the prepared image. The first method finds contours that are then used to identify and locate the target 36 . The second method finds potential corners of the target 36 that are then used to identify and locate the target 36 . While the description of these methodologies may suggest that they be performed serially, there is a potential in each of the methodologies for a parallel implementation as well. Beginning first with the contour methodology and turning now to flowchart 60 in FIG. 4 , the process starts at block 62 . The image is blurred at block 64 . In some embodiments, the image may be blurred using a Gaussian kernel of size ranging from about 5 to about 15. In a particular embodiment, a Gaussian kernel of size 11 was used. The blurred image is then posterized at block 66 .
Initially the image is posterized at level 2 creating an image of only black and white pixels. Additional levels of posterizing may also be included for some embodiments, with the posterizing level increasing for each subsequent level. For example, in some embodiments, up to seven posterizing levels (2,3,4,5,6,7,8) may be used, though other embodiments may use fewer posterized levels. While it was determined that posterized levels in excess of about seven did not add any appreciable advantage, additional posterized levels past seven may be utilized. If additional posterized levels are available (“YES” branch of decision block 68 ), then the blurred image is posterized at the next level at block 70 . Otherwise, if there are no additional levels (“NO” branch of decision block 68 ), then contours are determined for the first posterized image at block 72 . If there are additional posterized images (“YES” branch of decision block 74 ), then contours are determined for the next posterized image at block 76 until all images are processed. If there are no additional posterized images (“NO” branch of decision block 74 ), then the process ends at block 78 .
In some embodiments and as seen in flowchart 80 in FIG. 5 , the pixel boundaries of the posterized images are used to determine contour lines of the posterized image. The process begins at block 82 . An approximate center of the image is determined at block 84 . A color boundary is located at block 86 . In some embodiments that image 32 is a grey scale image with pixel values ranging from 0 (black) to 255 (white), and for simplicity, this algorithm will be further described with reference to grey scale images, though other embodiments may employ a full color palate. The boundary is then traversed in a counter-clockwise direction at block 88 , though in other embodiments a clockwise direction may be used.
If the boundary being traversed for the contour does not end at the point where the traverse started (“NO” branch of decision block 90 ), i.e. and open contour, the contour is discarded at block 92 . If the contour does end on at the point where the traverse started (“YES” branch of decision block 90 ), then a check is made to determine if the contour encloses the center of the image. If the contour does not enclose the center of the image (“NO” branch of decision block 94 ), then the contour is discarded at block 92 . Otherwise, if the contour does enclose the center of the image (“YES” branch of decision block 94 ), the then contour is kept at block 96 for further processing. The process ends at block 96 after either keeping or discarding the contour. The process of following the boundary to determine contours may be performed multiple times to capture each contour when multiple color boundaries are present in the image.
Before completing the analysis with the contours determined above, the second method utilizing corners of the target 36 is set out in FIGS. 6 and 7 . Starting with the flowchart 100 in FIG. 6 , the process begins at block 102 . Instead of blurring the image 32 as was done for the contours above, a Harris Corners algorithm as is known in the art is used to determine the corners in the image 32 at block 104 . The Harris corners algorithm may produce stray corners or real unwanted corners in the image. To assist in reducing the corners to only those of the target 36 , the image is cropped. To assist with the cropping, in some embodiments, the contour images above are combined into a single image and a bounding rectangle is determined which encompasses all of the contours at block 106 . In a specific embodiment, the contour images are combined using a logical OR function, though other methods of combining the images into a single image may also be used. The bounding rectangle is now used to crop the Harris corner image in block 108 . In one embodiment, the cropping of the image is accomplished using a logical AND function. A threshold ranging from about 32 to about 96 is applied to the cropped image to better define the corners in block 110 . In a particular embodiment, a threshold value of 64 is used, where any pixel values below 64 become black and any pixel values above 64 become white. A convex hull is then generated connecting each of the corners loaded in block 112 . The process ends at block 114 .
Similarly, and as seen in flowchart 120 in FIG. 7 , the process starts at block 122 . Instead of blurring the image or using the Harris corners algorithm, an eigenvalue corners algorithm as known in the art is utilized in order to determine the corners of the image 32 at block 124 . The rectangle used above to crop the Harris corner image is also found at block 126 and used to also crop the eigenvalue corner image at block 128 . The same threshold is applied to the cropped image at block 130 and a convex hull is generated through each of the corner points at block 132 . The process ends at block 134 .
Now that each of the images containing either contours or convex hulls is generated, triangles may be fit to each of the images which will then be used to determine the location and orientation of the target triangle 36 . Specifically, and with reference to flowchart 140 in FIG. 8 , the process begins at block 142 . The contour image generated from the first posterized image is retrieved in block 144 and an equilateral triangle oriented either upward, downward, to the left, or to the right is fit to the determined contour in block 146 . If there are additional contour images from additional posterized images (“YES” branch of decision block 148 ), then those contoured images are received in block 150 and an equilateral triangle oriented either upward, downward, to the left, or to the right is fit to the determined contour in block 146 . If there are no further contoured images (“NO” branch of decision block 148 ), then the convex hull generated from the Harris corners is retrieved at block 152 . An equilateral triangle oriented either upward, downward, to the left, or to the right is fit to the convex hull in block 154 . Similarly, the convex hull from the eigenvalue corners is retrieve at block 156 . An equilateral triangle oriented either upward, downward, to the left, or to the right is fit to the convex hull in block 158 . Finally, all of the fit triangles are analyzed to determine the orientation of the triangle in the target 36 at block 160 . In some embodiments, this orientation may be determined by the majority of the triangles oriented in the same direction. In other embodiments, other methods for determination may be used. The process ends at block 162 .
In order to fit the triangles in some embodiments, and as shown in flowchart 170 in FIG. 9 , each of the four orientations is tried with the best orientation being selected. The process starts at block 172 . An upward directed triangle is fit to the contour or convex hull in block 176 . If the triangle does not encompass the contour or the convex hull (“NO” branch of decision block 176 ), then the size of the triangle is increased at block 178 until the triangle does encompass the contour or convex hull. If the triangle does encompass the contour or convex hull (“YES” branch of decision block 176 ), then the next triangle selected from a downward directed, right directed, or left directed triangle is fit to the contour or convex hull at block 180 . If this triangle does not encompass the contour or convex hull (“NO” branch of decision block 182 ) then the size of the triangle is increased at block 184 until the triangle does encompass the contour or convex hull. If the triangle does encompass the contour or convex hull (“YES” branch of decision block 182 ) then the process repeats at block 180 until all four orientations of the triangle have been fit. If there are no other triangles to fit (“NO” branch of decision block 186 ), then the smallest of the four triangles is selected for the contour or convex hull at block 188 . The process ends at block 190 .
FIG. 10 illustrates an example of the triangles 192 - 208 that may have been fit for a particular embodiment having seven contoured images with the Harris and eigenvalue corner images, resulting in nine triangles. As set forth above with respect to flowchart 140 in FIG. 8 , six 192 , 194 , 196 , 200 , 204 , 206 of the nine triangles 192 - 208 are oriented in a upward direction. Based on that majority, the determination from the image detection algorithm is that the triangle in the target 36 is an upward directed triangle. The table in FIG. 11 illustrates exemplary data 214 , 216 , 216 for images generated respectively by an IR, NIR, and VIS sensor at several distances 212 . A series of images from each of these sensors may be generated at each of the distances 212 and evaluated with the image detection algorithm set out above. The results (in percentage correct) 214 - 218 may be determined based on the output of the algorithm and the actual orientation of the target 36 . This data can then be plotted on graph 220 as illustrated in FIG. 12 showing “frequency of seeing” curves 222 , 224 , 226 for each of the respective IR, NIR, and VIS sensors.
This data may now be used as an initial screening of sensors in order to reduce the number sensors to a select few that may then be subjected to testing by multiple human observers. Alternately, the data may then be used as a “quick and dirty” evaluation of a number of sensors to assist in selecting a sensor when the funding or time does not permit an exhaustive test by human observers. Furthermore, the data can be used to evaluate digital images combined, overlaid, or otherwise enhanced to again limit the combinations before presenting these enhanced images to actual human observers. Additionally, the triangle detection algorithm may also be used in conjunction with other image detection algorithms, such as a Landolt C recognition algorithm as discussed in co-pending U.S. application Ser. No. 13/025,624. The use of multiple detection algorithms may present a better evaluation of a sensor or image resolution or quality.
While the present invention has been illustrated by a description of one or more embodiments thereof and while these embodiments have been described in considerable detail, they are not intended to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus and method, and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the scope of the general inventive concept. | A method, apparatus and program product are presented for detecting an image. Ring contour images are created by blurring the image, posterizing the blurred image at a plurality of levels and creating the ring contour images from each of the posterized images. Convex hull images are created by creating a plurality of corner images from corners within the image located by at least two different corner algorithms, finding a bounding rectangle that encompasses the ring contour images, cropping the corner images using the bounding rectangle, applying a threshold to the cropped corner images, and creating the convex hull images by generating a convex hull from the corners in each of the cropped corner images. A plurality of triangles is created by fitting a triangle with an orientation to the ring contour images and the convex hull images. Finally the orientation of the triangle is determined from the plurality of triangles. | 6 |
FIELD OF INVENTION
This invention relates to valves, and more particularly to a valve for metering and repeatedly delivering minute quantities of fluid from a source thereof which may be pressurized.
BACKGROUND OF THE INVENTION
Delivery of very small amounts of liquids or gases is often of critical importance in research instrumentation. One way of dispensing an amount of liquid is to open a valve in a line containing fluid under pressure for a precise period of time. However, closely controlling the open time of an on-off valve in a flow line is not sufficiently accurate in many circumstances, because of variations in fluid viscosity, pressure differential and the like. A positive displacement metering system provides better control of volumetric flow rates. Representative prior positive displacement dispensers or metering devices are shown in U.S. Pat. No. 3,072,302, U.S. Pat. No. 3,353,712, U.S. Pat. No. 4,271,989, U.S. Pat. No 4,327,845 and U.S. Pat. No. 4,805,815.
U.S. Pat. No. 4,327,845 to Keyes et al. shows a dispensing apparatus having a rotary valve controlling access to a closed chamber containing a spring-loaded piston, acting as a fluid accumulator. A liquid, such as a viscous syrup or topping, under pressure, is admitted to the chamber, driving the piston upward, when the rotary valve is in one position; in a second position of the valve, the chamber is connected to an outlet, and the piston expels the contents of the chamber. A disadvantage of the keyes system is that the phase relationship between the inlet and outlet events cannot be changed. Also, there is no provision for changing the spring pressure on the piston, so as to obtain varying accumulator displacement.
U.S. Pat. No. 3,353,712 describes a dispensing system incorporating a fluid accumulator. The accumulator piston is downwardly biased by a spring centered on an adjusting screw which can be advanced to contact the back side of the piston physically, to limit its motion.
The use of pistons in very small displacement metering systems is problematic because of the exaggerated effects of any piston seal leakage. Furthermore, piston seals have drag which may be unacceptable for situations involving very low pressure fluid sources. Seal drag is also affected by the nature and temperature of the working fluid.
SUMMARY OF THE INVENTION
The invention device for metering small precise quantities of fluid from a source under pressure. Frequently the device is positioned to meter fluids from a pressurized source into a delivery line. The metering device of the invention functions effectively without regard to variations or fluctuations in temperature, pressure or viscosity of the metered fluid. The volume of fluid delivered may vary from a fraction of microliters to many microliters. Larger volumes may be provided by repeated deliveries of small volumes.
The metering device of the invention comprises a valve body defining a fluid flowpath, a fluid accumulator fixed to the body and in fluid communication with the flowpath, an inlet valve in the fluid flowpath upstream of the accumulator, an exhaust valve, independent of the inlet valve, in the flowpath downstream of the accumulator, and means for alternately opening and closing the inlet and outlet valves in such a way that at most one of the valves is open at a time.
DEFINITIONS
As used herein, the term "fluid" means any flowable material, including gases, liquids and granular solids. "Valve" means any device for controlling fluid flow along a flowpath. "Accumulator" means a closed chamber device connected to a flowpath and capable of reversibly receiving a volume of fluid from the flowpath, wherein the fluid volume is a function of the pressure of the fluid. "Hermetic" means leakproof. A "diaphragm" is a substantially flexible or distendable hermetic fluid barrier.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings,
FIG. 1 is a simplified sectional view of a metering device embodying the invention, with both its valves closed;
FIG. 2 is a view corresponding to FIG. 1, showing the device during its intake event;
FIG. 3 is a view corresponding to FIG. 1, showing the valve during its dwell event; and
FIG. 4 is a view corresponding to FIG. 1, showing the valve during its exhaust event.
DESCRIPTION OF THE PREFERRED EMBODIMENT
As shown in FIGS. 1-4, a metering device embodying the invention comprises a valve body 10 having an inlet port 12 and an outlet port 14, the direction of fluid flow into and out of the device being indicated by arrows. Flow through the device is controlled by opposed inlet and outlet valves 16 and 18, in conjunction with an accumulator 20. A small passage 22 connects the inlet port to the inlet valve bore; another passage 24 connects the accumulator with each of the valve bores; and a third passage 26 connects the outlet port to the outlet valve bore. The inlet and outlet ports 12 and 14, the passages 22 and 26, and the valves 16 and 18 thus define a flowpath for fluid passing through the device.
Inasmuch as the inlet and outlet valves are identical, only one need be described in detail. As illustrated in FIG. 2, there is a bore 30 in the body, provided with a large counterbore at 32, and having a frustoconical bottom 34 functioning as a seat. The conical surfaces of the inlet and outlet valves have a common apex A, in fact, they have common generatrices. The common apex of the cones lies within the inner end of the passage 24 extending from the accumulator. The valve stem 36, which is slightly smaller in diameter than the bore 30, terminates at a frustoconical head 38 conforming to the geometry of the seat 34. The valve stem is connected to, or unitary with, the plunger 40 of a solenoid (of which only the plunger is shown, the rest being conventional). To prevent leakage, the valve stem is sealed by an annular, flexible diaphragm 42, whose inner periphery is hermetically connected to the valve stem, and whose outer periphery is held stationary at the bottom of the counterbore by a retaining ring 44, so that there is no relative movement of parts and thus no requirement for sliding seals. The bottom of the counterbore is slightly concave, providing clearance for diaphragm flexure.
The accumulator 20, whose passage 24 joins the flowpath at the common apex of the valve seats, is mounted in a flat-bottomed bore 50 (see FIG. 3), the axis of which is in the center plane P of the device. The inlet and outlet valves extend perpendicularly to this plane, and the inlet and outlet ports are parallel to it. An inverted cup 52 is pressed or otherwise hermetically fit within the bore 50. The rim of the cup bears against the periphery of a flexible diaphragm 54, which normally lies flat against the bottom of the bore 50, but can distend outwardly, as shown in FIG. 3, upon receiving fluid from the passage 24. The diaphragm is biased toward the FIG. 1 position (flat) both by its own resilience, and by the force from a compression coil spring 56 within the cavity. The spring is supported on the axis of the accumulator between a centering post 58 on the diaphragm, and an adjustment screw 60 extending through the center of the cup face. By advancing the screw, one can increase the spring bias on the diaphragm, affecting both the outlet pressure and the displacement. Other biasing means, such as a volume of compressible fluid with the cup, could be substituted for the spring.
There is no mechanical interconnection between the valves, so they may be operated electronically independent of one another. It may also be observed that the opposed disposition of the inlet and outlet valves minimizes the passageway volume between them, which helps produce precise metering.
In operation, a source of pressurized fluid to be measured is connected to an inlet port, and a delivery line is connected to the outlet port. The inlet and outlet valves are initially both closed, as shown in FIG. 1, and the accumulator is empty, its diaphragm lying flat at the bottom of the blind bore. To meter an amount of fluid, the device is cycled through the inlet, dwell and exhaust events depicted in FIGS. 2-4, by opening and closing the valves alternately, in such a way that at most one is open at a time. This prevents through-flow, which would destroy the positive displacement feature of the device.
In FIG. 2, the inlet valve has been opened by energizing its solenoid, allowing fluid under pressure to pass to the accumulator. The diaphragm deflects outwardly, admitting a volume of fluid, which volume is dependent upon the pressure differential across it, the flexibility of the diaphragm, and the initial tension and spring rate of the spring. The inlet valve is held open long enough for the accumulator to fill, that is, to reach equilibrium.
The inlet valve is then closed (FIG. 3), sealing off the accumulator. It is essential that there be at least a brief dwell period during which both of the valves are closed.
Subsequently, as shown in FIG. 4, the outlet valve is opened, whereupon the fluid in the accumulator flows toward the outlet (assuming that the delivery line is maintained at a pressure below that of the pressure source). The outlet valve is kept open long enough to allow the accumulator to empty, i.e., until the diaphragm is again flat, as shown in FIG. 4. Thus, the accumulator functions as a pump during the exhaust stroke of each cycle, and its filled volume is the pump displacement. By changing the inlet pressure, replacing the accumulator diaphragm, or altering the setting of the adjustment screw, the effective displacement can be varied.
An advantage of the colinear valve arrangement is that the volume of the flowpath between them is minimized, reducing one source of uncertainty as to the metered volume, which is particularly significant when compressible fluids are used. It is also an advantage to be able to control the valve independently, because by varying the phase and duration of each valve event, one can optimize the metering system for example by reducing the length of each cycle to a minimum.
Inasmuch as the invention is subject to modifications and variations, it is intended that the foregoing description and the accompanying drawings shall be interpreted as illustrative of only one form of the invention defined by the following claims. | A pistonless device for metering a quantity of fluid from a source of fluid under pressure to a delivery line at a lesser pressure comprises a valve body defining a fluid flowpath, and including a fluid accumulator in fluid communication with the flowpath. An inlet valve upstream of the accumulator, and an exhaust valve downstream of the accumulator, are operated alternately in such a way that at most one of said valves is open at a time, so that positive metering displacement results. | 6 |
FIELD
[0001] The present disclosure relates to substrate processing systems, and more particularly to cyclical deposition such as atomic layer deposition or pulsed chemical vapor deposition of films.
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 the work 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] FIG. 1 shows an example of a method 10 for performing atomic layer deposition (ALD) of SiO 2 via reaction of silicon precursors with oxidizing co-reactants (ozone, oxidizing plasmas, etc.). Inert and/or reaction gases may be introduced into a process chamber. At 12 , a precursor dose is introduced into the process chamber. Some of the precursor is adsorbed onto an exposed surface of the substrate and remaining precursor is removed from the process chamber at 14 . For example, the substrate may include a semiconductor wafer. At 16 , the adsorbed precursor is activated, typically using plasma. At 20 , post activation removal of reactants is performed.
[0004] ALD processing may tend to have relatively long cycle times due to the amount of time required for the precursor to adsorb onto the exposed surface of the substrate. Contamination may occur due to the transients caused by cycling of the plasma on (during activation of the adsorbed precursor) and off (during dosing of the precursor).
SUMMARY
[0005] A method for processing a substrate in a substrate processing system includes a) flowing reactant gases into a process chamber; b) supplying plasma having a first power level; c) dosing the process chamber with the precursor, wherein the first power level is sufficient to enhance adsorption of the precursor on a surface of the substrate, and wherein the first power level is insufficient to decompose the precursor that is adsorbed; d) after a first predetermined period, removing a portion of the precursor that does not adsorb onto the substrate; e) activating the precursor that is adsorbed using plasma having a second power level, wherein the second power level is greater than the first power level and is sufficient to decompose the precursor that is adsorbed; and f) removing reactants from the process chamber.
[0006] In other features, the first power level is supplied from (b) to (f). The first power level is supplied during (c) and not during (e). The first power level is terminated after the second power level is supplied and the first power level is supplied prior to the second power level being terminated. The first power level is supplied by an inductively coupled plasma source and the second power level is supplied by a capacitively coupled plasma source. The first power level is supplied from (b) to (f).
[0007] In other features, the first power level is supplied by a capacitively coupled plasma source and the second power level is supplied by the capacitively coupled plasma source. The first power level is supplied from (b) to (f). The first power level is supplied by an inductively coupled plasma source and the second power level is supplied by the inductively coupled plasma source. The first power level is supplied by a remote plasma source and the second power level is supplied by a capacitively coupled plasma source. The first power level is below a threshold to permit significant parasitic chemical vapor deposition (CVD) and above a threshold to permit low energy activation of the precursors without destruction.
[0008] A method for processing a substrate in a substrate processing system includes a) flowing reactant gases into a process chamber including a substrate; b) supplying a first power level that is sufficient to promote rearrangement of molecules on a surface of the substrate; c) waiting a first predetermined period; d) after the first predetermined period, performing plasma-enhanced, pulsed chemical vapor deposition of film on the substrate by supplying one or more precursors while supplying a second power level for a second predetermined period, wherein the second power level is greater than the first power level; and e) removing reactants from the process chamber.
[0009] In other features, the first power level is supplied from (b) to (e). The first power level is supplied during (b) and (c) and not during (d). The first power level is terminated after the second power level is supplied and the first power level is supplied prior to the second power level being terminated. The first power level is supplied by an inductively coupled plasma source and the second power level is supplied by a capacitively coupled plasma source. The first power level is supplied from (b) to (e). The first power level is supplied by a capacitively coupled plasma source and the second power level is supplied by the capacitively coupled plasma source. The first power level is supplied from (b) to (e). The first power level is supplied by an inductively coupled plasma source and the second power level is supplied by the inductively coupled plasma source. The first power level is supplied by a remote plasma source and the second power level is supplied by a capacitively coupled plasma source. The first power level is supplied by a UV source.
[0010] A substrate processing system for processing a substrate includes plasma source. A controller is configured to flow reactant gases into a process chamber; dose the process chamber with precursor while the plasma source supplies plasma having a first power level, wherein the first power level is sufficient to enhance adsorption of the precursor on a surface of the substrate, and wherein the first power level is insufficient to decompose the precursor that is adsorbed; after a first predetermined period, remove a portion of the precursor that does not adsorb onto the substrate; activate the precursor that is adsorbed using plasma having a second power level, wherein the second power level is greater than the first power level and is sufficient to decompose the precursor that is adsorbed; and removing reactants from the process chamber.
[0011] Further areas of applicability of the present disclosure will become apparent from the detailed description, the claims and the drawings. 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 DRAWINGS
[0012] FIG. 1 is an example of a method for performing atomic layer deposition (ALD) according to the prior art.
[0013] FIG. 2 is a graph illustrating activation energy during deposition according to the present disclosure.
[0014] FIG. 3 is a functional block diagram of an example of a substrate processing system according to the present disclosure.
[0015] FIG. 4 is an example of a method for performing ALD according to the present disclosure;
[0016] FIG. 5 illustrates examples of pulse train steps during another reaction coordinate according to an example of the present disclosure;
[0017] FIG. 6 illustrates examples of pulse train steps during another reaction coordinate according to another example of the present disclosure;
[0018] FIG. 7 illustrates examples of pulse train steps during another reaction coordinate according to another example of the present disclosure;
[0019] FIG. 8 illustrates RF power during ALD according to the present disclosure; and
[0020] FIG. 9 illustrates an example of a method for performing pulsed CVD according to the present disclosure.
[0021] In the drawings, reference numbers may be reused to identify similar and/or identical elements.
DESCRIPTION
[0022] The present disclosure relates to systems and methods for depositing film using a cyclical deposition process such as but not limited to atomic layer deposition (ALD) or pulsed chemical vapor deposition (CVD). In some examples, the ALD and pulsed CVD may be used to perform conformal film deposition (CFD). Additional details relating to CFD may be found in commonly-assigned U.S. Pat. Nos. 6,905,737 and 7,871,676, which are hereby incorporated by reference in their entirety.
[0023] For example only, while the description set forth below relates to dual precursor activation for ALD using inductively coupled plasma (ICP), capacitively coupled plasma (CCP) or ultraviolet (UV) energy in combination with low energy ICP or CCP, other processes such as pulsed CVD and other activation methods such as using remote plasma sources can be used. As can be appreciated, the remote plasma may be introduced via a showerhead or other methods.
[0024] The different activation methods are capable of promoting molecules to different energy states to motivate different molecular activity. In one example, a first activation source promotes precursor molecules to have increased surface adsorption, which decreases dose time and increases throughput. A second activation source is applied sequentially to decompose the surface adsorbed precursor molecule in a manner consistent with standard plasma enhanced processing. For example only, the first activation source may remain ON during the entire process. For example only, the first activation source may use low RF power such as CCP=200W split by 4 pedestals. Processing in this manner may occur in a cyclical fashion.
[0025] The dual activation approach for processing of thin films is expected to provide kinetic improvement for the adsorption step. The dual activation approach is expected to reduce particles due to elimination of sharp transients from abrupt plasma transitions when turning the plasma ON and turning the plasma OFF. The improved surface mobility of activated precursors may be amenable to reflow and therefore gap fill applications can be supported. In addition, the activated precursors may overcome the relatively high dose time hurdles for existing ALD processes (such as SIN and SiC). The dual activation approach is also amenable to halide free processing.
[0026] FIG. 2 shows an example of an energy profile depicting a dual source activation method for ALD. In some examples, continuous activation is employed during the ALD cycle. The continuous activation may include remote plasma, inductively coupled plasma (ICP) or capacitively coupled plasma (CCP), or ultraviolet (UV) energy in combination with ICP or CCP. The power magnitude is varied over time. For example only, first and second power levels may be used during the ALD cycle.
[0027] In one example, a first RF power level is used during both dosing of the precursor and removal (e.g. purging or evacuation) of the precursor. The first RF power level is (1) below a threshold to permit significant parasitic chemical vapor deposition (CVD) and/or (2) adequate to permit low energy activation of the precursors without destruction.
[0028] Parasitic CVD or PECVD may be caused by interaction of co-reactants in the gas phase or interaction of plasma with a precursor in the gas phase. This would result in CVD or PECVD with mass-transport limited delivery of materials in a directional sense to the substrate. As used herein, significant parasitic CVD or PECVD may refer to with-in-wafer (WIW) non-uniformity (NU) greater than 2% 1-sigma (or WIW NU >2% 1s) and reduced step coverage (<90% sidewall to field thickness).
[0029] After dosing of the precursor and removal of the precursor, plasma having a second RF power level is used during activation to decompose the adsorbed precursor. Plasma having the second RF power level is above a threshold energy of activation (E a ) to decompose the precursor. The second RF power level may be supplied by the remote plasma source, the CCP power source, the ICP power source or another power source. As can be appreciated, a first RF power source providing the first RF power level may be turned ON and OFF or the first RF power source may remain on before and during operation of the second RF power source.
[0030] The first RF power level increases the energy of the precursor to a state that is sufficient to promote interaction with a substrate surface that is at a lower energy state and thus enhanced adsorption occurs while avoiding decomposition of the adsorbed precursor. The second RF power level is then used to decompose the surface adsorbed precursor and complete the reaction.
[0031] FIG. 3 shows an example of a substrate processing system 100 that includes a process chamber 102 . The substrate processing system 100 further includes a showerhead 110 to deliver process gases to the process chamber 102 .
[0032] A pedestal 114 may be connected to a reference potential such as ground. Alternatively an electrostatic chuck (ESC) may be used instead of the pedestal. The pedestal 114 may include a chuck, a fork, or lift pins (all not shown) to hold and transfer a substrate 116 during and between deposition and/or plasma treatment reactions. The chuck may be an electrostatic chuck, a mechanical chuck or various other types of chuck.
[0033] While FIG. 3 shows multiple RF power sources to create plasma in the process chamber 102 for illustration purposes, it will be understood that one RF power source that is operable at two RF power levels or any combination of two or more RF power sources may be used to supply the first RF power level and the second RF power level. For example only, two or more of a CCP power source, an ICP power source and a remote plasma source can be used.
[0034] For example, a CCP power source 120 may be used to supply RF power across the showerhead 110 and a pedestal 114 to create plasma. As can be appreciated, while the pedestal 114 is shown to be grounded, the RF power may be supplied to the pedestal 114 and the showerhead may be grounded. A remote plasma source 130 may provide remotely generated plasma to the process chamber 102 at one or more RF power levels. In some examples, the remote plasma source 130 may use microwave energy and/or a plasma tube. An ultraviolet (UV) source 132 may provide UV activation.
[0035] An ICP power source 133 may be used to supply current to a coil 135 . When a time-varying current passes through the coil 135 , the coil 135 creates a time-varying magnetic field. The magnetic field induces current in gas in the process chamber, which leads to the formation of plasma in the process chamber.
[0036] The process gases are introduced to the showerhead 110 via inlet 142 . Multiple process gas lines are connected to a manifold 150 . The process gases may be premixed or not. Appropriate valves and mass flow controllers (generally identified at 144 - 1 , 144 - 2 , and 144 - 3 ) are employed to ensure that the correct gases and flow rates are used during substrate processing. Process gases exit the process chamber 102 via an outlet 160 . A vacuum pump 164 typically draws process gases out of the process chamber 102 and maintains a suitably low pressure within the reactor by a flow restriction device, such as a valve 166 . A controller 168 may sense operating parameters such as chamber pressure and temperature inside the process chamber using sensors 170 and 172 . The controller 168 may control the valves and mass flow controllers 144 . The controller 168 may also control the plasma power source 120 .
[0037] FIG. 4 shows an example of a method 300 for performing ALD. At 312 , an inert carrier gas is provided in the process chamber. At 314 , reactant gases are provided. At 316 , an activation source supplying the first RF power level is initiated prior to, at the same time as or soon after dosing of the precursor occurs. The activation source can include supplying the first RF power level using the remote plasma source, the ICP power source or the CCP power source. Additional power may be supplied using the UV source. The first RF power level is (1) below a threshold to permit significant parasitic chemical vapor deposition (CVD) and/or (2) adequate to permit low energy activation of the precursors without destruction or decomposition of the adsorbed precursor.
[0038] At 320 , a precursor dose may be provided to the process chamber. At 324 , the non-adsorbed precursor is removed from the process chamber. At 326 , the adsorbed precursor is activated using the second RF power level to decompose the adsorbed precursor. The second RF power level may be supplied by the remote plasma source, the ICP power source or the CCP power source. The first RF power level may still be supplied while the second power level is being supplied. Alternately, the first RF power level may be transitioned off. The transition OFF may occur in an overlapping manner with a transition ON of the second RF power level to reduce transients. In other words, the second RF power level starts turning ON before or while the first RF power level starts turning off and vice versa.
[0039] When activation is complete, the second RF power level is no longer supplied and the RF power is returned to the first RF power level. At 328 , reaction by-products are removed. The removal (purging or evacuation) step can occur before, during or after the transition to the first RF power level. At 332 , control determines whether the process is done. If 332 is false, control returns to 312 for one or more additional cycles. Otherwise control ends.
[0040] FIGS. 5-7 show various examples of pulse train steps during a reaction coordinate. In FIG. 5 , the carrier gas is provided in step 1 to the process chamber during the process. Steady state adsorption activation at the first RF power level is provided in step 2 during the process. In step 3 , a precursor dose is provided to the process chamber. In step 4 , the precursor that is not adsorbed is removed. At step 5 , plasma activation of the adsorbed precursor is performed at the second RF power level. In step 6 , a post activation removal of reactants is performed. Steps 3 through 6 may be repeated as desired.
[0041] In FIG. 6 , the carrier gas is provided in step 1 to the process chamber during the process. Steady-state ICP-radical adsorption activation is provided at the first RF power level in step 2 during the process. In step 3 , a precursor dose is provided to the process chamber. In step 4 , the precursor that is not adsorbed is removed. At step 5 , plasma activation of the adsorbed precursor is performed at the second RF power level using CCP-radical and ion activation of the adsorbed precursor. In step 6 , a post activation removal of reactants is performed. Steps 3 through 6 may be repeated as desired.
[0042] In FIG. 7 , the carrier gas is provided in step 1 to the process chamber during the process. Steady-state low power CCP adsorption activation is provided at the first RF power level in step 2 during the process. In step 3 , a precursor dose is provided to the process chamber. In step 4 , the precursor that is not adsorbed is removed. At step 5 , plasma activation of the adsorbed precursor is performed using high power CCP radical and ion activation of the adsorbed precursor at the second RF power level. In step 6 , a post activation removal of reactants is performed. Steps 3 through 6 may be repeated as desired.
[0043] FIG. 8 illustrates RF power during operation according to the present disclosure. Low RF power is used during dose, removal and post activation removal of reactants steps. High RF power is used during plasma activation of adsorbed precursor.
[0044] FIG. 9 illustrates an example of a method for performing pulsed CVD according to the present disclosure. At 402 , inert carrier gas is provided. At 404 , an activation source is initiated at a first power level. At 408 , control waits a predetermined period. At 412 , one or more precursors are pulsed while using a plasma activation source at a second power level for a second predetermined period. After the second predetermined period, a removal of reactants operation may be performed at 416 . At 420 , if the process is not done, control returns to 408 and repeats the pulsed CVD. When the process is done, control ends.
[0045] In one example, the first RF power level is used before reactants are introduced at 412 . The first RF power level is (1) below a threshold to permit significant parasitic chemical vapor deposition (CVD) and/or (2) adequate to permit low energy activation a surface of the substrate. The first energy level may promote cracking of surface molecules and/or movement and rearrangement of molecules on the surface of the substrate. The first power level may be supplied by the UV source or any of the plasma sources listed above.
[0046] Plasma having the second RF power level is above a threshold energy of activation (E a ). The second RF power level may be supplied by any of the plasma sources listed above. As can be appreciated, a first RF power source providing the first RF power level may be turned ON and OFF or the first RF power source may remain on before and during operation of the second RF power source.
[0047] The embodiments herein are not limited to particular reactants or film types. However, an exemplary list of reactants is provided below.
[0048] In certain embodiments, the deposited film is a silicon-containing film. In these cases, the silicon-containing reactant may be for example, a silane, a halosilane or an aminosilane. A silane contains hydrogen and/or carbon groups, but does not contain a halogen. Examples of silanes are silane (SiH 4 ), disilane (Si 2 H 6 ), and organo silanes such as methylsilane, ethylsilane, isopropylsilane, t-butylsilane, dimethylsilane, diethylsilane, di-t-butylsilane, allylsilane, sec-butylsilane, thexylsilane, isoamylsilane, t-butyldisilane, di-t-butyldisilane, and the like. A halosilane contains at least one halogen group and may or may not contain hydrogens and/or carbon groups. Examples of halosilanes are iodosilanes, bromosilanes, chlorosilanes and fluorosilanes. Although halosilanes, particularly fluorosilanes, may form reactive halide species that can etch silicon materials, in certain embodiments described herein, the silicon-containing reactant is not present when a plasma is struck. Specific chlorosilanes are tetrachlorosilane (SiCl 4 ), trichlorosilane (HSiCl 3 ), dichlorosilane (H 2 SiCl 2 ), monochlorosilane (CISiH 3 ), chloroallylsilane, chloromethylsilane, dichloromethylsilane, chlorodimethylsilane, chloroethylsilane, t-butylchlorosilane, di-t-butylchlorosilane, chloroisopropylsilane, chloro-sec-butylsilane, t-butyldimethylchlorosilane, thexyldimethylchlorosilane, and the like. An aminosilane includes at least one nitrogen atom bonded to a silicon atom, but may also contain hydrogens, oxygens, halogens and carbons. Examples of aminosilanes are mono-, di-, tri- and tetra-aminosilane (H 3 Si(NH 2 ) 4 , H 2 Si(NH 2 ) 2 , HSi(NH 2 ) 3 and Si(NH 2 ) 4 , respectively), as well as substituted mono-, di-, tri- and tetra-aminosilanes, for example, t-butylaminosilane, methylaminosilane, tert-butylsilanamine, bis(tertiarybutylamino)silane (SiH 2 (NHC(CH 3 ) 3 ) 2 (BTBAS), tert-butyl silylcarbamate, SiH(CH 3 )—(N(CH 3 ) 2 ) 2 , SiHCl—(N(CH 3 ) 2 ) 2 , (Si(CH 3 ) 2 NH) 3 and the like. A further example of an aminosilane is trisilylamine (N(SiH 3 )).
[0049] In other cases, the deposited film contains metal. Examples of metal-containing films that may be formed include oxides and nitrides of aluminum, titanium, hafnium, tantalum, tungsten, manganese, magnesium, strontium, etc., as well as elemental metal films. Example precursors may include metal alkylamines, metal alkoxides, metal alkylamides, metal halides, metal β-diketonates, metal carbonyls, organometallics, etc. Appropriate metal-containing precursors will include the metal that is desired to be incorporated into the film. For example, a tantalum-containing layer may be deposited by reacting pentakis(dimethylamido)tantalum with ammonia or another reducing agent. Further examples of metal-containing precursors that may be employed include trimethylaluminum, tetraethoxytitanium, tetrakis-dimethyl-am ido titanium, hafnium tetrakis(ethylmethylamide), bis(cyclopentadienyl)manganese, bis(n-propylcyclopentadienyl)magnesium, etc.
[0050] In some embodiments, the deposited film contains nitrogen, and a nitrogen-containing reactant must be used. A nitrogen-containing reactant contains at least one nitrogen, for example, ammonia, hydrazine, amines (e.g., amines bearing carbon) such as methylamine, dimethylamine, ethylamine, isopropylamine, t-butylamine, di-t-butylamine, cyclopropylamine, sec-butylamine, cyclobutylamine, isoamylamine, 2-methylbutan-2-amine, trimethylamine, diisopropylamine, diethylisopropylamine, di-t-butylhydrazine, as well as aromatic containing amines such as anilines, pyridines, and benzylamines. Amines may be primary, secondary, tertiary or quaternary (for example, tetraalkylammonium compounds). A nitrogen-containing reactant can contain heteroatoms other than nitrogen, for example, hydroxylamine, t-butyloxycarbonyl amine and N-t-butyl hydroxylamine are nitrogen-containing reactants.
[0051] In certain implementations, an oxygen-containing oxidizing reactant is used. Examples of oxygen-containing oxidizing reactants include oxygen, ozone, nitrous oxide, carbon monoxide, etc.
[0052] While many examples discussed herein include two reactants (e.g., A and B, or a principal reactant and an auxiliary reactant), it will be appreciated that any suitable number of reactants may be employed within the scope of the present disclosure. In some embodiments, a single reactant and an inert gas used to supply plasma energy for a surface decomposition reaction of the reactant may be used. Alternatively, some embodiments may use three or more reactants to deposit a film.
[0053] The embodiments herein may use various different process sequences. Table 1 below recites non-limiting examples of process parameters that may be used to implement this technique to deposit a silicon oxide film.
[0000]
TABLE 1
Oxidant
Si dose
Purge 1
RF plasma
Purge 2
Compound(s)
O 2, N 2 O,
Silanes,
Inert gas,
NA
Inert gas,
CO 2 , mixtures,
e.g., BTBAS
e.g., Ar/N 2
e.g., Ar/N 2
e.g., mixture
of N 2 O and O 2
Flow Rate
3-10 slm, e.g.
0.5-5 ml/min,
10-90 slm,
NA
10-90 slm,
4.5 slm O 2 +
e.g., 2 ml/min
e.g., 45 slm
e.g., 45 slm
5 slm N 2 O
premixed
Time
Continuous
0.1-2 s,
0.1-5 s,
0.1-5 s,
Optional,
e.g., 0.8 s
e.g., 0.5 s
e.g. 1 s
if performed
0.01-5 s,
e.g., 0.09 s
[0054] Table 2 below recites various non-limiting examples of process parameters that may be used to implement this process flow to deposit a silicon oxide film.
[0000]
TABLE 2
Oxidant
Si dose
Purge 1
RF plasma
Purge 2
Compound(s)
O 2, N 2 O,
Silanes, e.g.
Inert gas,
NA
Inert gas,
CO 2 , mixtures,
BTBAS
e.g., Ar/N 2
e.g., Ar/N 2
e.g., mixture
of N 2 O and O 2
Flow Rate
3-10 slm,
0.5-5 ml/min,
10-90 slm,
NA
10-90 slm,
e.g. 4.5 slm
e.g., 2 ml/min
e.g., 45 slm
e.g., 45 slm
O 2 + 5 slm
N 2 O premixed
Time
50 ms-5 s,
50 ms-1 s.
Continuous,
50 ms-5 s,
Continuous,
e.g., 0.15 s
e.g., 0.2 s
inert gas
e.g., 0.15 s
inert gas
Concurrent with
only: 0.1-5 s,
only: Optional,
RF or may flow
e.g., 0.4 s
if performed
oxidant 0.001-1 s
0.01-5 s,
prior to RF to
e.g., 0.09 s
stabilize flow
[0055] The compounds, flow rates, and dosage times in the above tables are examples. Any appropriate silicon-containing reactant and oxidant may be used for the deposition of silicon oxides. Similarly, for the deposition of silicon nitrides, any appropriate silicon-containing reactant and nitrogen-containing reactant may be used. Further, for the deposition of metal oxides or metal nitrides, any appropriate metal-containing reactants and co-reactants may be used. The techniques herein are beneficial in implementing a wide variety of film chemistries
[0056] The foregoing description is merely illustrative in nature and is in no way intended to limit the disclosure, its application, or uses. 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 upon a study of the drawings, the specification, and the following claims. 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 one or more steps within a method may be executed in different order (or concurrently) without altering the principles of the present disclosure.
[0057] In this application, including the definitions below, the term controller may be replaced with the term circuit. The term controller may refer to, be part of, or include an Application Specific Integrated Circuit (ASIC); a digital, analog, or mixed analog/digital discrete circuit; a digital, analog, or mixed analog/digital integrated circuit; a combinational logic circuit; a field programmable gate array (FPGA); a processor (shared, dedicated, or group) that executes code; memory (shared, dedicated, or group) that stores code executed by a processor; other suitable hardware components that provide the described functionality; or a combination of some or all of the above, such as in a system-on-chip.
[0058] The term code, as used above, may include software, firmware, and/or microcode, and may refer to programs, routines, functions, classes, and/or objects. The term shared processor encompasses a single processor that executes some or all code from multiple controllers. The term group processor encompasses a processor that, in combination with additional processors, executes some or all code from one or more controllers. The term shared memory encompasses a single memory that stores some or all code from multiple controllers. The term group memory encompasses a memory that, in combination with additional memories, stores some or all code from one or more controllers. The term memory may be a subset of the term computer-readable medium. The term computer-readable medium does not encompass transitory electrical and electromagnetic signals propagating through a medium, and may therefore be considered tangible and non-transitory. Non-limiting examples of a non-transitory tangible computer readable medium include nonvolatile memory, volatile memory, magnetic storage, and optical storage. | A method includes flowing reactant gases into a process chamber. Plasma having a first power level is supplied using a plasma source. The process chamber is dosed with the precursor. The first power level is sufficient to enhance adsorption of the precursor on a surface of the substrate and is insufficient to decompose the precursor that is adsorbed. After a first predetermined period, the method includes removing a portion of the precursor that does not adsorb onto the substrate. The precursor that is adsorbed is activated using plasma having a second power level using the plasma source. The second power level is greater than the first power level and is sufficient to decompose the precursor. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Patent Application No. 60/707,351, filed on Aug. 11, 2005 and titled “Portable Mast Structure,” which is hereby incorporated by reference herein.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable.
BACKGROUND
[0003] The present invention relates generally to mast structures used in drilling wells. More particularly, the present invention relates to portable mast structures used for drilling wells.
[0004] In land-based drilling operations it is often desirable to be able to transport a drilling rig to a site where the drilling operations will take place and then be able to move the rig to the next site once operations are complete. Drilling rigs comprises a plurality of systems that all must be interconnected and assembled to support drilling activities The process of disassembling, transporting, and reassembling a drilling rig is complex and time consuming.
[0005] The components and systems that make up a drilling rig are generally transported on trailers between drilling sites. Once on site, the components have to be unloaded and assembled. Drilling can not commence until the entire rig is unloaded and assembled. In many instances, the operators of the drilling rigs only collect rental fees when the rigs are involved in drilling operations Therefore, the time and expenses involved in transporting and assembling a drilling rig are preferably minimized. In many cases, auxiliary equipment, such as a crane and/or forklift, is required to assemble the drilling rig This auxiliary equipment must also be transported between drilling sites, further adding to the complexity and cost of moving a rig.
[0006] Thus, there remains a need in the art for systems and methods for transporting and assembling portable drilling rigs, which overcome some of the foregoing difficulties while providing more advantageous overall results.
SUMMARY OF THE PREFERRED EMBODIMENTS
[0007] Embodiments of the present invention include a portable drilling mast structure comprising a lower drilling mast having a lower end pivotally coupled to a base. A hinge is coupled to an upper end of the lower drilling mast and a lower end of an upper drilling masts The drilling mast structure has a first position wherein the lower drilling mast is parallel to the base and the upper drilling mast is disposed between the lower drilling mast and the base. The drilling mast structure has a second position wherein the lower drilling mast is perpendicular to the base and the upper drilling mast is aligned with the lower drilling mast.
[0008] Thus, the embodiments of present invention comprise a combination of features and advantages that enable substantial enhancement of drilling rig transportation and assembly. These and various other characteristics and advantages of the present invention will be readily apparent to those skilled in the art upon reading the following detailed description of the preferred embodiments of the invention and by referring to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] For a more detailed description of the preferred embodiment of the present invention, reference will now be made to the accompanying drawings, wherein:
[0010] FIG. 1 is an elevation view of an erected drilling mast constructed in accordance with embodiments of the present invention;
[0011] FIG. 2 illustrates the drilling mast of FIG. 1 collapsed for transport;
[0012] FIG. 3 illustrates the drilling mast of FIG. 1 collapsed and positioned at a drill site;
[0013] FIG. 4 illustrates the drilling mast of FIG. 1 in an upright position with the upper drilling mast folded down;
[0014] FIG. 5 illustrates the drilling mast of FIG. 1 as the upper drilling mast is rotated relative to the lower drilling mast;
[0015] FIG. 6 illustrates the drilling mast of FIG. 1 in a horizontal position with the upper drilling mast aligned with the lower drilling mast;
[0016] FIG. 7 illustrates a folding drilling mast configured for use with a elevated substructure;
[0017] FIG. 8 illustrates the folding drilling mast of FIG. 7 connected to the substructure; and
[0018] FIG. 9 illustrates the drilling mast of FIG. 7 in an operational position.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] Referring now to FIG. 1 , drilling rig 100 comprises folding drilling mast 200 , drawworks 300 , top drive 310 , iron roughneck 320 , mud pumps 340 , hydraulic power unit 350 , hydraulic control unit 360 , and compressor 370 . Folding drilling mast 200 , drawworks 300 , hydraulic power unit 350 , hydraulic control unit 360 , and compressor 370 are mounted to trailer 110 , which is positioned on ramp 112 . Top drive 310 and iron roughneck 320 are mounted to folding drilling mast 200 . Top drive 310 is coupled to cable 304 , which is run over sheaves 302 at the top of folding drilling mast 200 to drawworks 300 . Mud pumps 340 are mounted to skids 342 having upper surface 344 .
[0020] Folding drilling mast 200 comprises lower drilling mast 202 and upper drilling mast 204 connected by hinge 206 . Lower drilling mast 202 is rotatably coupled to trailer 110 by pivot 208 . Main hydraulic cylinder 210 is coupled to trailer 110 and lower drilling mast 202 . Support structure 212 couples lower drilling mast 202 to ramp 112 once drilling mast 200 is fully erected. Sheaves 302 are mounted to the top of upper drilling mast 204 .
[0021] Referring now to FIG. 2 , folding drilling mast 200 can be collapsed and transported on trailer 110 via truck 114 . Top drive 310 and iron roughneck 320 may remain installed on folding drilling mast 200 during transport and installation. When collapsed for transport, upper drilling mast 202 is stored below and latched to lower drilling mast 204 . Upper drilling mast 202 remains coupled to lower drilling mast 204 at hinge 206 . Lower drilling mast 204 is coupled to trailer 110 at pivot 208 .
[0022] Once at the drilling site, trailer 110 is driven onto ramp 112 and secured in place, as is shown in FIG. 3 . Mud pumps 340 are also placed adjacent to ramp 112 such that their upper surfaces 344 are aligned with the upper surface 116 of trailer 112 . Folding drilling mast 200 is erected by extending hydraulic cylinder 210 so as to rotate the drilling mast about pivot 208 . Drilling mast 200 is rotated until in a substantially vertical position, as shown in FIG. 4 . Once in the vertical position, upper drilling mast 204 is unlatched from lower drilling mast 202 by releasing connection 214 .
[0023] Once upper drilling mast 204 is unlatched, hydraulic cylinder 210 is retracted so that lower drilling mast 202 moves back toward a horizontal position. As lower drilling mast 202 rotates, the force of gravity will cause upper drilling mast 204 to rotate about hinge 206 . As upper drilling mast 204 rotates, upper cylinder 216 and pivot aim 218 engage the upper drilling mast. As lower drilling mast 202 is lowered upper drilling mast 204 will contact upper surfaces 114 and 344 . Pivot arm 21 8 acts to control the rate at which upper drilling mast 204 rotates and makes sure the upper drilling mast rotates past vertical as it contacts upper surfaces 114 and 344 .
[0024] As lower drilling mast 202 moves toward horizontal, upper drilling mast 204 slides along upper surfaces 114 and 344 until both the upper and lower drilling masts are aligned and in a substantially horizontal position, as shown in FIG. 6 . Once aligned, upper drilling mast 204 is fixably connected to lower drilling mast 202 and folding drilling mast 200 can be configured for drilling operations. Once upper drilling mast 204 is fixably connected to lower drilling mast 202 , hydraulic cylinder 210 can be extending, which will rotate folding drilling mast 200 to the vertical position, as shown in FIG. 1 . Once fully vertical, support structure 212 can be connected to drilling mast 200 so as to reinforce the drilling mast during drilling operations.
[0025] Folding drilling mast 200 is collapsed for storage and transport by essentially reversing the installation procedure described above. Support structure 212 is removed and hydraulic cylinder 210 is retracted to lower folding drilling mast 200 to the horizontal position of FIG. 6 . Once horizontal, upper drilling mast 204 is partially disconnected from lower drilling mast 202 so that it can rotate about hinge 206 . Hydraulic cylinder 210 is then extended to raise lower drilling mast 202 back toward a vertical position. As lower drilling mast 202 is raised, upper drilling mast 204 will rotate about hinge 206 as is shown in FIG. 5 .
[0026] As lower drilling mast 202 reaches vertical, as shown in FIG. 4 , upper drilling mast 204 will be positioned adjacent to the lower drilling mast. Connector 214 is then engaged so that the position of upper drilling mast 204 relative to lower drilling mast 202 is maintained as hydraulic cylinder 210 is retracted The retraction of hydraulic cylinder 210 lowers drilling mast 200 back to a horizontal position where it is fully collapsed and ready for transport, as shown in FIGS. 2 and 3 .
[0027] FIGS. 7-9 illustrate a folding drilling mast 400 being installed on substructure 500 . Folding drilling mast 400 is transported to a drilling site via trailer 410 . Folding drilling mast 400 comprises lower drilling mast 402 and upper drilling mast 404 that are rotatably coupled at hinge 408 . Substructure 500 comprises platform 502 , hydraulic cylinder 504 , and legs 506 . Connections 508 and 510 extend from the top of platform 502 .
[0028] Referring now to FIG. 7 , folding drilling mast 400 is moved into a position adjacent to substructure 500 . The base of folding drilling mast 400 is moved onto platform 502 such that lower drilling mast 402 is rotatably coupled to connection 508 , as shown in FIG. 8 . Erecting arm 406 is extended from lower drilling mast 402 and is connected to cable 512 . Folding drilling mast 400 is erected using substantially the same process as described in reference to FIGS. 3-6 . As hydraulic cylinder 504 is extended, platform 502 will raise and cable 512 will pull arm 406 such that drilling mast 400 rotates about connection 508 . Once drilling mast 400 is fully vertical, as shown in FIG. 9 , lower drilling mast 402 is coupled to connection 510 and the drilling mast is secured for drilling operations.
[0029] While preferred embodiments of this invention have been shown and described, modifications thereof can be made by one skilled in the art without departing from the scope or teaching of this invention. The embodiments described herein are exemplary only and are not limiting. Many variations and modifications of the system and apparatus are possible and are within the scope of the invention. Accordingly, the scope of protection is not limited to the embodiments described herein, but is only limited by the claims that follow, the scope of which shall include all equivalents of the subject matter of the claims. | A portable drilling mast structure comprising a lower drilling mast having a lower end pivotally coupled to a base. A hinge is coupled to an upper end of the lower drilling mast and a lower end of an upper drilling mast. The drilling mast structure has a first position wherein the lower drilling mast is parallel to the base and the upper drilling mast is disposed between the lower drilling mast and the base. The drilling mast structure has a second position wherein the lower drilling mast is perpendicular to the base and the upper drilling mast is aligned with the lower drilling mast. | 4 |
This application claims the benefit of U.S. Provisional Application No. 60/276,693, filed on Mar. 16, 2001, the entire contents of which are hereby incorporated by reference.
FIELD OF THE INVENTION
The present invention relates to a magnetic head cluster for a data storage device having read/write transducers, which are used for communicating with a magnetic recording medium, and lapping guides, which are used during lapping processes while fabricating the magnetic head cluster. Further, the present invention relates to a method for making a magnetic head cluster.
BACKGROUND OF THE INVENTION
Thin film magnetoresistive (MR) read and inductive write transducers are widely used for magnetic heads in data storage devices, such as disk drives and linear tape drives. Various types of MR read heads are known in the art, including anisotropic magnetoresistive (AMR) read heads, giant magnetoresistive (GMR) read heads, and spin valve read heads. In typical magnetic tape read/write heads, multiple merged MR read/inductive write transducers are grouped into a single structure called a magnetic head cluster. Each of the transducers is typically aligned in the cluster along one edge, known as an air bearing surface (ABS) in disk drive technology and known as a tape bearing surface (TBS) for tape drives (for simplicity this surface will be referred to herein as a tape bearing surface), which faces a recording medium during normal read/write operation. In general, each transducer of a cluster provides an unique read/write channel.
The demand for data storage has been increasing in recent years and this demand has put pressure on fabrication processes for more efficient and cost effective methods and devices. In order to keep up with this demand, attempts to improve various aspects of magnetic head technology include increasing the sensitivity of the magnetic heads, reducing manufacturing costs, and simplifying manufacturing processes.
A conventional manufacturing process for fabricating a magnetic head cluster will be described next with reference to FIGS. 1 and 2 . As shown in FIGS. 1 and 2 , a magnetic head cluster 115 is made by forming a plurality of inner merged MR read/inductive write transducers 100 and outermost merged MR read/inductive write transducers 105 , a plurality of electrical lapping guides 175 , and a plurality of terminals 107 on a single wafer 110 . The wafer 110 can be formed from any material which has high wear resistance, strength, fracture toughness, and good electrical conductivity, such as an alumina titanium-carbide (Al 2 O 3 /TiC) ceramic wafer. The processes used to form the transducers 100 and 105 on the wafer 110 typically include a combination of lithography, deposition (vacuum or plating), and etching steps, all of which are known in the art. The transducers 100 and 105 are grouped into the clusters 115 , which are separated from one another by separation kerfs 120 . As shown in FIG. 1 , the clusters 115 are aligned in rows and columns defined by the separation kerfs 120 . Once the process of forming the clusters 115 is complete, the wafer 110 is cut along the separation kerfs 120 , dividing the wafer 110 into a plurality of clusters. This well-known process of cutting the wafer along the kerfs is commonly referred to as “dicing.”
As mentioned above, the transducers 100 and 105 included in each cluster 115 are typically merged MR read/inductive write transducers. As shown in FIG. 3 , a conventional MR read transducer 125 typically includes an MR stripe 130 , which exhibits variations in resistance when exposed to a magnetic field. The stripe height SH of the MR stripe 130 must be controlled within a tight tolerance, such as within a few micro-inches, so that a sensed magnetic signal can generate an optimum change in a resistance of the MR stripe 130 . The inductive write transducer 135 typically comprises various layers of poles 140 and insulating material 145 , and also includes an electrical coil 150 . The region of the inductive write transducer 135 closest to an upper edge 155 (shown on FIG. 2 ) of the cluster 115 , where the two poles are separated only by a thin insulating layer, is typically called a throat 160 . As will be explained later, the region closest to the upper edge 155 will eventually be lapped to form a tape bearing surface. As is known in the art, the throat height TH must also be controlled within a tight tolerance for the transducer to generate an optimum magnetic signal.
When the separation kerfs 120 are formed on the wafer 110 , a slight amount of excess substrate is provided along the upper edge 155 of each cluster. The reason for providing this slight amount of excess substrate is that the dicing process is not precise enough to achieve the optimum stripe height SH and throat height TH for each transducer 100 and 105 . So, rather than inadvertently cutting the stripe 130 or throat 160 too short while dicing the wafer 110 , the stripe 130 and throat 160 are intentionally left too long and later are carefully shortened by a process known as lapping.
FIG. 4 shows an exaggerated view of the conventional lapping process in order to provide a clear illustration. The broken line in FIG. 4 represents a portion of the cluster 115 which has already been removed by the lapping process. In FIG. 4 , a controller 185 operates to activate and halt a lapping plate rotator 190 . The lapping plate rotator 190 , when activated, causes a lapping plate 165 to rotate relative to the cluster 115 , thereby grinding the upper edge 155 . Eventually, a sufficient amount of upper edge 155 is ground away to form a tape bearing surface 170 . The tape bearing surface 170 is a surface of the magnetic head cluster 115 which will face a recording medium (not shown) when the magnetic head cluster 115 is used for read/write operations. A lapping plate pressure applicator 195 also receives signals from the controller 185 for continuously adjusting the amount of pressure being applied to the cluster 115 during the lapping process. The lapping plate pressure applicator 195 may include, for example, one or more dual action air cylinders (not shown) for applying varying amounts of pressure to different points on the cluster 115 in order to provide for skew control. The controller 185 senses an electrical resistance of the electrical lapping guides 175 , which changes as portions of the electrical lapping guides 175 adjoining the upper edge 155 are ground away. The lapping process is complete once the portions of the cluster 115 are removed up to line A, which indicates the desired position of the tape bearing surface 170 of the cluster 115 .
During the lapping process, the excess portion of the substrate 210 is carefully ground away by introducing an abrasive material, such as a diamond slurry (not shown), between the rotating lapping plate 165 and the upper edge 155 of the fixed cluster 115 . In order to provide for precise control during the lapping process, the electrical lapping guides 175 are typically provided between each outermost transducer 105 and a respective outer edge 180 of each cluster 115 . Once the electrical lapping guides 175 reach a predetermined resistance, the controller 185 halts the motion of the lapping plate 165 . Ideally, the predetermined resistance is selected so that the target stripe height SH and throat height TH are achieved.
In general, lapping guides and separation kerfs, which are useful during the manufacturing of magnetic head clusters, have no functional purpose during normal operation of a magnetic head cluster. As mentioned above, electrical lapping guides are typically provided between an outermost transducer and an outer edge of each cluster. Thus, the size of each cluster is larger than its functional size, which need only include transducers. Therefore, from a functional standpoint, the wafer space occupied by lapping guides and separation kerfs is wasted. Moreover, in order to minimize the unit cost per cluster, efficient use of wafer space is important. For this reason, recent efforts have been made to increase the efficiency with which wafer space is utilized by reducing the amount of wafer space used for lapping guides and separation kerfs. Accordingly, separation kerfs have been reduced to a very small size so that more clusters can be put onto the same wafer.
U.S. Pat. No. 6,027,397 discloses further efforts to efficiently utilize wafer space, wherein the cluster size is reduced by putting the lapping guides onto the separation kerfs. U.S. Pat. No. 5,588,199 discloses another attempt to efficiently utilize wafer space, wherein the number of transducers per wafer is increased by adding a resistor network, which is used as a lapping guide, inside the transducers. Therefore, there is no need for a separate electrical lapping guide. A similar approach can be found in U.S. Pat. No. 5,772,493 by using an external magnetic excitation field to the transducer and measuring the resistance of the MR element in response to variations in the applied magnetic excitation field.
Despite these past attempts to increase the efficiency with which wafer space is utilized, there continues to be a need to improve wafer utilization and simplify manufacturing processes.
BRIEF SUMMARY OF THE INVENTION
In view of the above shortcomings with the prior art, an object of the present invention is to provide a magnetic head cluster that includes lapping guides arranged in such a way so as to reduce cluster size allowing for more clusters per wafer.
Another object of the present invention is to provide a method of making a magnetic head cluster which allows for a reduced cluster size so that more clusters per wafer may be formed.
In order to achieve the above objects, a magnetic head cluster is provided that comprises a substrate having a surface with at least two transducer elements disposed thereon and at least one resistive element that is disposed between any two of the at least two transducer elements.
In accordance with another aspect of the present invention, a method of fabricating a magnetic head cluster having an edge portion is provided that comprises the steps of providing a substrate having a surface, forming at least two transducer elements on the surface, forming at least one resistive element on the surface between any two of the at least two transducer elements, and lapping the edge portion of the magnetic head cluster.
Depending on the design of the lapping processes, each cluster can contain one or more electrical lapping guides. Such lapping guides can be any combination of analog and/or digital “switch” types that are well-known in the field.
In accordance with the present invention, the size of electrical lapping guides can be reduced and the electrical lapping guides can be positioned between the transducers so that the size of the magnetic head cluster can be reduced to its functional size. As a result, the total number of clusters that can be produced on a wafer is increased.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is illustrated by way of example and not limited in the figures of the accompanying drawings, in which like reference numbers indicate similar parts:
FIG. 1 is a plan view of a wafer containing a plurality of conventional magnetic head clusters formed in rows and columns;
FIG. 2 is a plan view of a conventional magnetic head cluster;
FIG. 3 is a cross sectional view of a magnetoresistive (MR) read and inductive write transducer 100 taken along line III—III of FIG. 2 ;
FIG. 4 is a plan view of a lapping system for a conventional cluster;
FIG. 5 is a plan view of a magnetic head cluster in accordance with the present invention; and
FIG. 6 is a plan view of a lapping process in accordance with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 5 shows a preferred embodiment of the present invention. A magnetic head cluster 315 of the present invention includes a plurality of inner merged MR read/inductive write transducers 300 and outermost merged MR read/inductive write transducers 305 , a plurality of electrical lapping guides 375 , and a plurality of terminals 307 formed on a substrate 410 . The substrate 410 can be a portion of a wafer (not shown) formed from any material which has high wear resistance, strength, fracture toughness, and good electrical conductivity, such as an alumina titanium-carbide (Al 2 O 3 /TiC) ceramic wafer. The transducers 300 and 305 , lapping guides 375 , and terminals 307 can be formed on the substrate 410 by any of the known transducer-forming processes.
The transducers 300 and 305 are preferably MR read and inductive write transducers as discussed above, and can include any combination of AMR, GMR, and spin valve read heads. The electrical lapping guides 375 may be composed of any type of electrically resistive material, including any combination of analog and/or digital switch types that are well-known in the art. The terminals 307 can be composed of any type of electrically conductive material, such as plated gold, suitable for transferring electrical signals between the transducers 300 and 305 and an external interface (not shown).
As shown in FIG. 5 , the electrical lapping guides 375 are each provided between adjacent inner transducers 300 and/or between adjacent inner transducers 300 and outermost transducers 305 . In other words, in this preferred embodiment, there are no lapping guides 375 provided between an outermost transducer 305 and an adjacent outer edge 380 of the cluster 315 . Compared to the conventional magnetic head cluster 115 shown in FIG. 2 , the magnetic head cluster 315 is reduced in size since an excess amount of the substrate 410 is not required to accommodate electrical lapping guides 375 beyond the outermost transducers 305 . Thus, the cluster 315 is reduced to its actual functional size, allowing for more clusters 315 to be formed on a wafer.
The transducers 300 and 305 included in the cluster 315 are preferably merged inductive write and MR read transducers. The transducers 300 and 305 can have the same configuration as the conventional transducer 100 , which is shown in FIG. 3 . As shown in FIG. 3 , an MR read transducer 125 includes an MR stripe 130 , which experiences variations in resistance when exposed to a magnetic field. The stripe height SH of the MR stripe 130 must be controlled within a tight tolerance, such as within a few micro-inches, so that a sensed magnetic signal can generate an optimum change in a resistance of the MR stripe 130 . The inductive write transducer 135 comprises various layers of poles 140 , and insulating material 145 , and also includes an electrical coil 150 . The region of the inductive write transducer 135 closest to an upper edge 355 of the cluster 315 , where the two poles are separated only by a thin insulating layer, is typically called a throat 160 . As will be explained later, the region closest to the upper edge 355 will eventually be lapped to form a tape bearing surface. As is known in the art, the throat height TH must also be controlled within a similarly tight tolerance for the transducer to generate an optimum magnetic signal.
FIG. 6 shows an exaggerated view of a lapping process in accordance with the present invention in order to provide a clear illustration. The broken line in FIG. 6 represents a portion of the cluster 315 which has already been removed by the lapping process. In FIG. 6 , a controller 385 operates to activate and halt a lapping plate rotator 390 . The lapping plate rotator 390 , when activated, causes the lapping plate 365 to rotate relative to the cluster 315 , thereby grinding the upper edge 355 . Eventually, a sufficient amount of upper edge 355 is ground away to form a tape bearing surface 370 . The tape bearing surface 370 is a surface of the magnetic head cluster 315 which will face a recording medium (not shown) when the magnetic head cluster 315 is used for read/write operations. A lapping plate pressure applicator 395 also receives signals from the controller 385 for continuously adjusting the amount of pressure being applied to the cluster 315 during the lapping process. The lapping plate pressure applicator 395 may include, for example, one or more dual action air cylinders (not shown) for applying varying amounts of pressure to different points on the cluster 315 in order to provide for skew control. The controller 385 senses an electrical resistance of the electrical lapping guides 375 , which changes as portions of the electrical lapping guides 375 adjoining the upper edge 355 are lapped away. The lapping process is complete once the portions of the cluster 315 are removed up to line A, which indicates the desired position of a tape bearing surface 370 of the cluster 315 .
During the lapping process, an excess portion of substrate 410 is carefully ground away from the magnetic head cluster 315 by introducing an abrasive material, such as a diamond slurry (not shown), between a lapping plate 365 and an upper edge 355 of the cluster 315 . In order to provide for precise control during the lapping process, a plurality of electrical lapping guides 375 are provided between selected ones of the plurality of transducers 300 and 305 . Once the electrical lapping guides 375 reach a predetermined resistance, the controller 385 halts the motion of the lapping plate 365 . Ideally, the predetermined resistance is selected so that the target stripe height SH and throat height TH are achieved.
Although the present invention has been fully described by way of preferred embodiments and methods, one skilled in the art will appreciate that other embodiments and methods are possible without departing from the spirit and scope of the present invention. | A magnetic head cluster is provided along with a method of making a magnetic head cluster. The magnetic head cluster comprises a substrate having a plurality of magnetoresistive (MR) read and inductive magnetic write transducers and a plurality of terminals formed thereon. A plurality of lapping guides are also provided on the substrate between adjacent transducers. | 6 |
[0001] The present application hereby claims priority under 35 U.S.C. §119 on German patent application number DE 10247150.9 filed Oct. 9, 2002, the entire contents of which are hereby incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The invention generally relates to a method for postprocessing raw magnetic resonance data. The invention also generally relates to a magnetic resonance tomography unit or a magnetic resonance spectroscopy unit which is respectively matched to such a method for postprocessing raw magnetic resonance data.
BACKGROUND OF THE INVENTION
[0003] The aim of processing raw magnetic resonance data, which can originate both from magnetic resonance spectroscopy units and from magnetic resonance tomography units, is to extract the medically relevant information from the raw magnetic resonance data as well as possible. In the case of magnetic resonance tomography, the aim is accordingly a picture with high resolution of detail and low noise. That is to say, the aim is for a picture with high edge sharpness and a high signal to noise ratio (SNR).
[0004] In the case of magnetic resonance spectroscopy, the aim is to obtain from the raw data a linear spectrum with high resolution and with a high SNR. The quality in the processing of raw magnetic resonance data is thus firstly in the edge sharpness and image sharpness, i.e. in sharp pictures with high contrast. Secondly, it is in the production of a high SNR, so that the essence of the picture or of the spectrum is highlighted.
[0005] In the case of the various approaches to achieving this aim, it is usually not possible to increase the image sharpness and the SNR simultaneously. This drawback has a direct effect on the quality of the magnetic resonance tomography and spectroscopy. To improve the resolution of detail, radio-frequency “blue” noise is superimposed on a picture, for example. This produces a subjective increase in the resolution of detail. A likewise subjective improvement in the resolution is brought about in a similar manner by the application of high pass filters to the image data. This also amplifies the image noise, however.
[0006] To improve the SNR in the case of magnetic resonance pictures, known filters (such as the Hanning filter, the Fermi filter or the cosine filter in the frequency domain) are applied to the raw magnetic resonance data. The action of such filters is known from the literature, e.g.: F. J. Harris, Proc. IEEE, Vol. 66, No 1 (1978): “On the Use of Windows for Harmonic Analysis with the Discrete Fourier Transform”. It is also possible to apply postprocessing filters in the space domain, for example a mean filter, median filter or ARMA filter.
[0007] In addition, U.S. Pat. No. 4,463,375 discloses a method for medical image processing. This method specifies a reduced-noise version of a first processed image which has been obtained from a multiplicity of measurements in a multipicture system, e.g. using a computer tomography unit. The method first involves producing a second image with a high SNR from the multiplicity of measurements. The first image is then processed using a filter which reduces the noise. The second image is processed using a filter which is complementary to this filter. The weighted combination of the two images produces the reduced-noise version of the first processed image.
SUMMARY OF THE INVENTION
[0008] An embodiment of the invention includes an object of specifying a method for processing raw magnetic resonance data and a magnetic resonance tomography unit and a magnetic resonance spectroscopy unit which produce pictures or spectra with high edge sharpness without impairing the image noise, i.e. the SNR, in the process.
[0009] For the method, an embodiment of the invention achieves an object by virtue of a method having the method features below being carried out in order to postprocess raw magnetic resonance data. In a first step, the raw magnetic resonance data are filtered using a first filter. These filtered data are Fourier transformed in a second step. The absolute value for the Fourier transformed data is then formed in a third step and in this way a first magnetic resonance signal is obtained. In a fourth step, the unfiltered, original raw magnetic resonance data are Fourier transformed. This is followed in the fifth step by second absolute value formation for the unfiltered Fourier transformed data. Finally, weighted combination of the two magnetic resonance signals is performed and in this way the postprocessed magnetic resonance signal is obtained.
[0010] The method includes the weighted combination of two magnetic resonance signals, the magnetic resonance signals having been obtained from the same raw magnetic resonance data once with and once without filtering. Through suitable choice of the filter and of the parameters for the weighted combination, a picture which is optimized in terms of the representation wanted from a medical point of view is extracted.
[0011] One advantage of the method is that the SNR is significantly improved following the weighted combination of the two magnetic resonance signals and that an edge-emphasized magnetic resonance signal is produced at the same time. In comparison with the method from U.S. Pat. No. 4,463,375, the involvement for this method is significantly reduced. This occurs since it is firstly based only on the raw data from a single measurement, and since it is secondly independent of an image with a high SNR which is produced from a plurality of measurements.
[0012] In one particularly simple extension of the method, the raw magnetic resonance data are filtered using a second filter before the second magnetic resonance signal is produced. This allows the second magnetic resonance signal to be influenced and thus allows it to improve the weighted combination. The use of the unfiltered raw magnetic resonance data in the original method corresponds to the application of the identity filter and is faster to execute.
[0013] A weighted combination within the context of an embodiment of the invention is in this case a mathematical combination of the absolute values of the two magnetic resonance signals. These have the same local coding and represent the echo signal from a magnetic resonance measurement, for example in a one-dimensional or multidimensional pixel structure, following the Fourier transformation. In this case, the combination, which is usually addition, is spatially consistent, i.e. the same spatial areas are combined.
[0014] By way of example, combination takes place pixel by pixel. The weighting is effected using a weighting factor. For a spatial area of one of the two magnetic resonance signals, this weighting factor depends on the information content, e.g. the intensity, of the same spatial area in the other magnetic resonance signal. By way of example, the weighting factor can have a linear dependency on the information content or can have any other beneficial nonlinear dependency on the information content of the spatial area. The weighting factor can be produced, by way of example, by a mathematical step function which sets the weighting factor to a small value or zero below a previously stipulated threshold value for the absolute value of the magnetic resonance signal in question.
[0015] One advantage of weighted combination is that the SNR is significantly improved following the weighted combination of the two filters. Further, this data weighting produces an edge-emphasized profile in the magnetic resonance signal.
[0016] The method relates to the postprocessing of raw magnetic resonance data from a single measurement and is not dependent on whether the raw data belong to a single picture or whether they belong to a picture from a series of pictures which show a development over time, for example. The raw magnetic resonance data can be raw data from a measurement in a magnetic resonance spectroscopy unit or else raw data from a picture in a magnetic resonance tomography unit.
[0017] Accordingly, an embodiment of the invention achieves an object for a magnetic resonance tomography unit by use of a magnetic resonance tomography unit which is matched to a method for postprocessing raw magnetic resonance data with the method features above. In this case, the raw magnetic resonance data are referred to as a spin echo signal or an echo signal, for example. The magnetic resonance signals correspond to the one-dimensional or multidimensional magnetic resonance pictures, for example.
[0018] An embodiment of the invention achieves an object for a magnetic resonance spectroscopy unit by use of a magnetic resonance spectroscopy unit which is matched to a method for postprocessing raw magnetic resonance data with the method features above. In this case, spectroscopic data, e.g. the FID (Free Induction Decay) signal, are postprocessed.
[0019] In one particularly beneficial embodiment of the method, the filters are applied to the raw magnetic resonance data after demodulation thereof. This allows the filters to be applied in their customary form of representation in the frequency domain. Applying the filters after demodulation has the advantage that the filters can be very narrowband.
[0020] In one particularly advantageous embodiment, the first filter is a low pass filter which filters rapid changes out of the raw data and thus suppresses radio-frequency oscillations. By way of example, the low pass filter can be a type of Hanning filter.
[0021] In another embodiment the second filter is a high pass filter which passes only the rapid changes in the signal, which are also caused by noise, for example. Magnetic resonance signals which have been high pass filtered show an excessive increase in rapidly rising edges.
[0022] In one particularly advantageous embodiment which uses self-weighting for the combination, the weighted combination is effected as follows:
C = A + λ ( B A max ) K B [ Equation 1 ]
[0023] In this case, A and B are magnetic resonance signals which are subjected to weighted combination by low pass filtering (A) and high pass filtering (B), for example. A max is the maximum of the magnetic resonance signal A. The two parameters λ and κ determine the contribution level of the magnetic resonance signal B to the postprocessed magnetic resonance signal C. The quotient of B and A max brings about amplified correction of the pixels which have a high absolute value in the magnetic resonance signal B. The values of λ and κ need to be ascertained empirically on the basis of their influence and their optimum effect on the magnetic resonance signal. In this case, the values of λ and κ are preferably between 1 and 3.
[0024] One advantage of the quotient which normalizes B to A max is that an uncontrolled signal contribution for B is avoided in regions in which there is actually nothing to correct or to improve.
[0025] The weighted combination of suitably filtered magnetic resonance signals has the advantage that, in a single magnetic resonance measurement, the noise in the resultant magnetic resonance signal is lower than with linear addition or subtraction of the two filtered magnetic resonance signals.
[0026] In particular embodiments, the method from the invention can be applied to raw magnetic resonance data which cover a one-dimensional or multidimensional space which is to be examined. Depending on the application, one-dimensional sections, two-dimensional sectional views or three-dimensional volume representations are shown, for example, in magnetic resonance technology. The raw magnetic resonance data contain the dimension of the respective picture.
[0027] In one advantageous embodiment, the dimensionality of the Fourier transformation performed during the method is chosen such that the dimension of the raw magnetic resonance data is retained. Thus, the method can be applied, by way of example, to two-dimensional magnetic resonance sectional views or to three-dimensional volume representations. Even in the case of magnetic resonance spectra, one-dimensional or multidimensional representation, for example in three dimensions, is possible.
[0028] In one particularly advantageous embodiment of the method, two locally coded magnetic resonance signals are combined such that the contribution of one magnetic resonance signal to the weighted combination is formed by multiplying this magnetic resonance signal by a weighting factor. The weighting factor depends on the other magnetic resonance signal such that it is greater for a large magnetic resonance signal than for a small magnetic resonance signal.
[0029] In one specific embodiment, the weighting factor has a nonlinear dependency on the absolute value of a magnetic resonance signal. At least in one dimension of the raw magnetic resonance data, the same nonlinear dependency is used in order to have the same effect on the image sharpness, for example, over all the pixels in this dimension.
[0030] In one particular embodiment of the method, the raw magnetic resonance data are processed using a plurality of filters before the differently filtered magnetic resonance signals are subsequently combined by means of weighted combination to form a single postprocessed magnetic resonance signal.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] A plurality of exemplary embodiments of the method, of the magnetic resonance tomography unit and of the magnetic resonance spectroscopy unit based on the invention will become more fully understood from the detailed description of preferred embodiments given hereinbelow and the accompanying drawings, which are given by way of illustration only and thus are not limitative of the present invention, and wherein:
[0032] [0032]FIG. 1 shows a flowchart of an exemplary embodiment of the method which has been implemented in a magnetic resonance tomography unit,
[0033] [0033]FIG. 2 shows a flowchart of an exemplary embodiment of the method in which two filtered magnetic resonance signals are subjected to weighted combination,
[0034] [0034]FIG. 3 shows a numerical simulation of the processing of raw magnetic resonance data using a spin echo signal which is brought about by a square object in the image gradient of a magnetic resonance tomography unit,
[0035] [0035]FIG. 4 shows a numerical simulation of the processing when a low pass filter is applied to the spin echo signal from FIG. 3,
[0036] [0036]FIG. 5 shows a numerical simulation of the processing when a high pass filter is applied to the spin echo signal from FIG. 3,
[0037] [0037]FIG. 6 shows an abscissa detail from FIGS. 3 to 5 to illustrate the action of the method using the edge-emphasized profile which is achieved by the weighted combination,
[0038] [0038]FIG. 7 shows an enlargement of FIG. 6 in the area of an edge of the square object,
[0039] [0039]FIG. 8 shows a numerical simulation of the processing of raw magnetic resonance data for the case of magnetic resonance spectroscopy using an FID signal which has been formed by the sum of three Lorentz lines, and
[0040] [0040]FIG. 9 shows a comparison of the magnetic resonance spectrum obtained by weighted combination with the low pass filtered magnetic resonance spectrum, both magnetic resonance spectra having been normalized to the same noise.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0041] [0041]FIG. 1 schematically shows the flow of the method and the necessary components which are required within a magnetic resonance tomography unit 1 for the flow of the method. In a magnetic resonance tomography unit 1 having a conventional magnet and gradient system (not shown explicitly) used for local coding, a radio-frequency transmitter 3 is used to irradiate an examined object 5 with radio-frequency pulses. The electromagnetic signals emitted by the examined object 5 are received using a radio-frequency receiver 7 . The output signals from the radio-frequency receiver 7 form the raw magnetic resonance data in the form of a spin echo signal 9 .
[0042] These data are postprocessed within a data processing installation 11 . The latter subjects them to weighted combination with one another either in unfiltered form or in a form filtered using various filters 13 in a weighting unit 15 . The result is a postprocessed magnetic resonance signal 17 in the form of a magnetic resonance picture.
[0043] [0043]FIG. 2 shows a flow chart of an exemplary embodiment of the method in which two filtered magnetic resonance signals are subjected to weighted combination in the data processing installation 11 . In this case, the spin echo signal 9 is first demodulated in a demodulation unit 19 , so that it is available in the k domain with the dimension of the sampling. Next, the spin echo signal 9 is supplied to two data processing units 21 having a respective filter. There, the spin echo signal is filtered once using the low pass filter processor 23 and the other time using the high pass filter processor 25 .
[0044] Following the subsequent Fourier transformations 27 and the absolute value formations 29 , one firstly obtains the low pass filtered magnetic resonance picture 31 and the high pass filtered magnetic resonance picture 33 , respectively. These two magnetic resonance pictures are combined in the weighting unit 15 by weighted addition to form a single postprocessed magnetic resonance picture 35 . The weighted addition is carried out by inputting parameters 37 using an input unit 39 . The parameters 37 determine the weighting of the pixel 41 in the high pass filtered magnetic resonance picture 33 on the basis of the same pixel 43 in the low pass filtered magnetic resonance picture 31 . With a suitable choice of weighted addition and its parameters, the postprocessed magnetic resonance picture 35 has both a high SNR and great edge sharpness.
[0045] When the method is used with a magnetic resonance spectroscopy unit, the flowchart is comparable with that in FIGS. 1 and 2. The only difference is that raw data from magnetic resonance spectra are filtered and subjected to weighted addition by means of the method in order to achieve a higher resolution and a greater SNR.
[0046] FIGS. 3 to 5 show the results of a numerical simulation of a spin echo signal for a square object in the field gradient of the magnetic resonance tomography unit 1 . The simulation relates to a section through a square object and illustrates the effect of the method on the object's edge sharpness. The object is in the area of the 128 pixels in the simulation.
[0047] The figures respectively show the real and imaginary parts 51 and 53 of the echo signal after a filter has been applied to the echo signal. They show the filter function and the complex-value spin echo signal above a k x axis in the k domain. Various filter functions clarify the action of the filters on the echo signal in the K domain. In addition, FIGS. 3 to 7 show the result of Fourier transforming the filtered complex-value echo signal with subsequent absolute value formation. In this way, a simulated measurement result is obtained from a magnetic resonance tomography unit, in this case a one-dimensional section through the square object. The sectional view of the measurement result is plotted above the corresponding spatial axis.
[0048] [0048]FIG. 3 shows the real part 51 and the imaginary part 53 of the unfiltered echo signal and also the result of the Fourier transformation and of the absolute value formation for the unfiltered echo signal, in this case referred to as identity simulation result 57 . In the simulation, no filter 55 was applied to the echo signal in this case. The oscillations in the identity simulation result 57 in the area of the rising and falling edges can be seen clearly. These oscillations limit the edge sharpness in the simulated (unpostprocessed) measurement.
[0049] [0049]FIG. 4 shows the influence of the low pass raw data filter 59 on the spin echo signal. The low pass raw data filter 59 has been applied in the form of a Hanning filter F H to the spin echo signal, the Hanning filter F H having the following form in the one-dimensional k domain:
F T,H =F H =½×[1+cos(2π( j−N/ 2)/N)] [Equation 2]
[0050] In this case, N is the number of sampling points in the picture in one dimension. The filter modulation follows a cosine function whose maximum is shifted by N/2, that is to say to the center of the k domain. The index j describes the jth sampling point. The filter suppresses the marginal area of the k domain with lower intensity in the echo signal. This can clearly be seen from the reduced oscillation amplitude of the filtered spin echo signal in the marginal area. The low pass simulation result 61 in FIG. 4 shows a rounded edge for the square object. This can also be seen in FIGS. 5 and 6.
[0051] In FIG. 5, the simulation is carried out for a high pass raw data filter 63 , with the high pass filter in the k domain being a modulated Hamming filter F H provided with an offset:
F H;H =( F H +Offset)×cos n (π( j−N/ 2)/ N ) [Equation 3]
[0052] In this case, the modulation of the Hanning filter F H takes place with a cosine function to the power of n, with the minima of the cosine function being at the two ends and in the center of the k domain. The additional minima at the ends have the advantage that they cause no additional artefacts in the Fourier transformation. Thus, by way of example, the “truncation artefact” in the Fourier transformation is suppressed.
[0053] In this case, the offset parameter of the modulated Hanning filter has the value 0.2 and the power n of the cosine modulation has the value 1. The high pass raw data filter 63 amplifies the wings of the echo signal in the k domain. In the real part 51 and in the imaginary part 53 of the filtered echo signal, it is possible to see the amplified amplitude of the echo signal oscillations in the marginal areas and a suppression in the central area. The high pass simulation result 65 shows a marked overshoot in the area of the edges of the square object.
[0054] [0054]FIG. 6 shows a detail from the simulation results in the area of the pixels 35 to 55 , i.e. in the area of the rising edge. The oscillations in the identity simulation result 57 can clearly be seen. The edge of the square object is rounded in the case of the low pass simulation result 61 .
[0055] The high pass simulation result 65 shows a pronounced signal overshoot right in the area of the rise. Using the weighted addition of the two filtered simulation results, it is now possible to achieve an edge-emphasized postprocessing result 67 . To this end, a weighted combination has been performed in line with the equation 1 already indicated above. In this case, the low pass simulation result 61 corresponds to the magnetic resonance signal A and the high pass simulation result 65 corresponds to the magnetic resonance signal B.
[0056] The parameters κ and λ are set such that a maximum sharpness is produced in the edge area. In this case, κ and λ are usually between the values 1 and 3. The level obtained for the weighting of the contribution of B depends on the ratio of the absolute value in the respective pixel in B to the maximum value A max of the pixels in A, i.e. the higher the value of the high pass simulation result 65 in a pixel, the higher its contribution. κ then performs a type of linear weighting, while λ weights the influence of this quotient as a power of the ratio of B and A, that is to say indicates how greatly the correction of A is determined by the ratio of magnitudes for B with respect to A. The parameters κ and λ have been set to the values 0.6 and 2.3, respectively, in FIGS. 6 and 7.
[0057] Besides the edge sharpness, the SNR of the postprocessing result 67 is also increased, and is now comparable to the SNR of the low pass simulation result 61 . This can be seen from the suppression of the signal before the rising edge, i.e. there is a low base contribution outside the object.
[0058] [0058]FIG. 7 shows a further enlarged detail from the simulated measurement results. The representation focuses on the edge area of the square object in the area of pixels 42 to 55 with signal levels between 10 and 13. It can clearly be seen how the greatly oscillating identity simulation result 57 is freed from the radio-frequency oscillations using the low pass filter. Next, the weighted addition fills the corner area of the square object on account of the high signal absolute values in the high pass simulation result 65 . The oscillations in the identity simulation result 57 are also called “ringing”. This artefact, which is also called truncation artefact, is suppressed using the method of the invention.
[0059] [0059]FIG. 8 shows the flow of the method applied to raw magnetic resonance data from a simulated magnetic resonance spectroscopy measurement in which an FID signal 71 is measured which is formed by the sum of three Lorentz lines ( 73 , 75 , 77 ). FIG. 8 shows the real parts of the FFT spectra involved in the method. In the simulation, a noise contribution has been added to the synthesized FID signal 71 . Low pass filtering of the FID signal 71 results in the low pass filtered spectrum 79 , and high pass filtering results in the high pass filtered spectrum 81 . Following the weighted combination of the two filtered spectra, the postprocessed magnetic resonance spectrum 83 is obtained. It is possible to see markedly reduced noise and high resolution of the three Lorentz lines on account of the use of the method of the invention.
[0060] In FIG. 9, the postprocessed magnetic resonance spectrum 83 is compared with the low pass filtered spectrum 79 . To clarify the influence of the method, the two spectra have been normalized to the same noise in this case. The narrower line widths and a considerable increase in the contrast in the postprocessed magnetic resonance spectrum 83 are clearly evident.
[0061] Exemplary embodiments being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the present invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims. | A method is for producing a map from raw magnetic resonance data from a magnetic resonance tomography unit or a spectrum from raw magnetic resonance data from a magnetic resonance spectroscopy unit. The method involves the raw data being filtered, preferably using a high pass filter and using a low pass filter. Next, the two absolute values of the filtered, Fourier transformed raw magnetic resonance data are used to produce the map or the spectrum by a weighted combination. The method is distinguished in that the signal to noise ratio can be improved together with an increase in the edge sharpness. | 8 |
BACKGROUND
1. Field of the Invention
The invention relates to a bioreactor, comprising
a reactor bag with a predominantly flexible bag wall which has a rigidly formed bearing area for housing a stirrer serving to circulate contents of the bag, a shaftless stirrer, parts of which are permanently magnetic, housed inside the bag in the bearing area, and a coil arrangement positioned outside the reactor bag with which coil arrangement a rotating magnetic field can be produced, which magnetic field interacts, in a manner exerting a torque on the stirrer, with the permanent-magnetic areas thereof.
2. Description of the Related Art
The invention further relates to a reactor bag for a bioreactor, comprising a predominantly flexible bag wall which has a rigidly formed bearing area for housing a shaftless stirrer serving to circulate the contents of the bag, at least parts of the stirrer being permanently magnetic.
Finally, the invention relates to a stirrer to circulate the contents of a bioreactor, parts of which stirrer being permanently magnetic and comprising a plurality of paddle-like circulation elements affixed to a holder.
Such bioreactors, reactor bags and stirrers for same are known from U.S. Pat. No. 8,123,199 B2.
As is known, bioreactors serve as containers for fluids in which biological processes, such as fermentation or cell growth, are intended to take place in a controlled manner. Due to the metabolic activity of the microorganisms involved, local changes arise in the concentration of various chemical components. To maintain the same, or at least controlled, concentration conditions in the entire container, the fluid in the reactor must be stirred occasionally; preferably, in a constant manner. To avoid contamination, the stirrers are generally arranged in the interior of the otherwise closed reactor container (except for specific inlets and outlets). One difficulty is causing the stirrers located in the interior of the reactor container to move in the desired stirring direction by means of drive mechanisms usually arranged outside of the reactor container.
For bioreactors with rigid walls, such as steel tanks, a familiar solution is to affix the actual circulation elements of the stirrer, such as impellers, on a shaft that penetrates the container wall in a sealed bearing such that the stirrer shaft can simply be coupled with the drive shaft of a motor of any desired configuration.
Recently there has been a steady increase in the use of bioreactors whose actual container is designed as a flexible bag for single use. Advantages include the cost-effective manufacture of the foil bags, straightforward and space-saving storage, ease of sterilization and contamination security, as well as dispensing with the need for laborious cleaning after use. However, the problem of appropriately circulating the contents of the bag has not been definitively solved. In particular, versions with stirrer shafts that penetrate the bag wall are regarded as disadvantageous as this increases the risk of contamination, considerably increases the amount of space required for storage and, because of the necessity of providing a sealed penetration point for the shaft, renders the manufacture of the bags more complicated and expensive.
The category-defining patent U.S. Pat. No. 8,123,199 B2 discloses a shaftless stirrer having a plurality of impellers around a flat, cylindrical holder, wherein the flat, cylindrical holder is housed in a correspondingly shaped rigid vessel forming the bottom of the reactor bag. At least part of the cylindrical holder is designed to be permanently magnetic and interacts with an external magnetic field that penetrates the vessel wall. The external magnetic field is designed as a rotational field, so that the stirrer holder, along with the paddle-like circulation elements, is caused to rotate in its bearing vessel. This known device has several disadvantages. On the one hand, it is limited in that the position of the stirrer is restricted to the bottom region of the reactor bag, which can be expected to result in insufficient mixing of the reactor contents in tall bioreactors. On the other hand, the stirrer is not axially fixed in its bearing vessel—rather, to the contrary, in order to reduce bearing friction, axial raising of the stirrer by the external magnetic field is described. This means that during transport, the stirrer can easily fall out of its bearing and damage the bag walls with its sharp-edged paddles.
It is the problem of the present invention to further develop category-defining bioreactors, reactor bags and stirrers so as to overcome the disadvantages of the prior art. In particular, bioreactors and/or reactor bags with significantly reduced space requirements during storage and/or transport are to be provided. Also improved mixing of the reactor contents and safer transport and storage options are intended to result.
SUMMARY OF THE INVENTION
This problem is solved in that a rigid profile ring made of non-magnetic material, e.g. plastic, is arranged in a segment of height of the reactor bag—however preferably not at the height of its top edge—as a bearing area in which the stirrer formed as the rotor spanning the cross-section of the bag is rotatably housed by means of a guide rail, the magnetic field of the electric coil arrangement interacting with at least one permanent magnet arranged in the radially outer area of the rotor.
The problem is further solved in that a rigid profile ring made of a non-magnetic material, e.g. plastic, is arranged as a bearing area at a segment of height of the reactor bag—however preferably not at the height of its top edge—in which the stirrer formed as the rotor spanning the cross-section of the bag is rotatably housed in an axial and radial manner by means of a guide rail.
The problem also is solved in that the stirrer is formed as a rotor having a central body and at least three spokes extending radially from the central body, the rotor having at least one permanent magnet arranged in its radially outer area and at least one guide element of an outer guide rail.
The essential subject of the invention is the special design of the bearing area and the corresponding design of the stirrer. The stirrer spans the entire cross-section of the bag and is housed in a profile ring which forms the rails of a guide rail at its radially outer area, the profile ring extending around the circumference of the reactor bag. The magnetic interaction to drive the stirrer in a motorized way also takes place in this radially outer mechanical interaction area between the rotor and its guide. The magnetic forces acting between the outer coil arrangement and the permanent magnet(s) arranged in the outer area of the stirrer penetrate the profile ring, which therefore must be made of a non-magnetic material, e.g. plastic. The entire stirrer arrangement can therefore be designed such that it occupies only very minimal axial space in the apparatus and moreover can be arranged at any desired axial position within the reactor bag. It is also conceivable that multiple such stirrer arrangements could be arranged at different axial positions within the reactor bag so as to ensure sufficient mixing of the entire reactor content in very tall bioreactors. Due to the minimal axial height of each stirrer arrangement, the walls of the reactor bag, which are inherently flexible, are only reinforced with “ribs”, flexible wall areas remaining between these profile rings forming the “ribs” such that the reactor bag can be compressed like a bellows for storage and transport, which significantly reduces the storage space required. With appropriate design of the guide rail, it will be impossible for any of the rotors to dislodge from their guides, which means that there is no risk of the bag walls being damaged in the compressed state and that in the expanded state, it is possible to begin stirring operation immediately without any prior assembly steps.
In a preferred embodiment, the profile ring penetrates the flexible bag wall and is bonded to it. The bonded connection, which can be implemented by means of welding or gluing, ensures the seal-tightness of the reactor bag, including in the area of the stirrer arrangement. Since the profile ring radially penetrates the bag wall, direct access to its external side is ensured from outside of the reactor bag. This feature takes on special importance in connection with the special designs of the motorized stirrer drive described below. However, it is generally also conceivable that the profile ring be bonded to the internal side of the otherwise flexible bag wall, the bag wall covering the radially external contours of the profile ring tightly. This version is generally reserved for devices with very thin, preferably elastic, bag wall material.
The profile ring preferably has a circumferential guide groove open to the bag interior in which at least one guide shoe arranged radially outside of the rotor is guided axially and radially. Special design versions of the guide shoe for rotors of different designs are discussed below. However, with respect to all such embodiments, the guide shoe is surrounded by the guide groove on at least three sides, such that both radial and axial support is ensured in this type of bearing.
Alternatively, it is also conceivable that the profile ring have a circumferential ridge oriented to the bag interior, which ridge projects into at least one groove element arranged at the radially outer side of the rotor such that the rotor is guided axially and radially. This version essentially represents the kinematic reverse of the preferred embodiment described above. One skilled in the art will easily be able to translate the embodiments of the groove-guided guide shoe described in detail below to the corresponding kinematically reversed embodiments with a ridge-guided groove element.
To reduce friction, a further development of the invention provides that at no fewer than three positions on the circumference of the profile ring, radially oriented roller bearings and/or axially oriented, opposing pairs of roller bearings project into the guide groove with spring action, or, in embodiments with a guide ridge, project out of it.
Alternatively or additionally to this, it is conceivable that at no fewer than three positions on the circumference of the profile ring, radially oriented slide bearing springs and/or axially oriented, opposing pairs of slide bearing springs project into the guide groove, or, in embodiments with a guide plane, project out of it. The surfaces of the slide bearing springs are preferably coated with friction-reducing material, such as polytetrafluoroethylene.
Of course, in principle, it is also conceivable that such or similar friction-reducing elements be provided on the rotor, especially on the guide shoe and/or on the groove element. The reason for the general preference for embodiments with a guide groove as opposed to embodiments with a guide ridge is the special suitability of the former for an especially advantageous further development of the invention. This provides that the guide groove on the exterior side of the profile ring form a projection having at least one axial mounting surface on which an electric coil arrangement designed as a separate unit or unit group is arranged and/or arrangeable, the coil arrangement being capable of generating the magnetic field. In this connection, an axial mounting surface is to be understood as a surface with surface normals oriented parallel to the axial direction on which a mounting element, in this case the electric coil arrangement in particular, is arrangeable such that a radial overlap occurs. In this way, a radial overlap of the guide shoe guided in the interior of the guide groove with the coil arrangement arranged on the exterior axial mounting surface can be realized, which serves to minimize the distance between the coil arrangement that generates the magnetic field and a permanent magnet arranged in the external region of the stirrer, or potentially even in the area of the guide shoe. This serves to maximize the interaction between the permanent magnet and the coil arrangement such that only small permanent magnets and/or low coil currents are required to achieve a predetermined drive power. It is advantageous if there is more than one axial mounting surface.
Rather, it is preferred that the guide groove on the exterior side of the profile ring be surrounded on three sides, by a form-fitting connection, by an electric coil arrangement designed as a separate unit or unit group, which coil arrangement is capable of generating the magnetic field. The interaction between the coils and permanent magnets can be yet further augmented by means of this measure.
One skilled in the art recognizes that the rearward accessibility of the profile ring has special importance in connection with this embodiment. In particular, this makes it conveniently possible to separate elements intended for single use (bag, rotor and profile ring) from reusable elements (coil inserts).
Regarding the design of the rotor, it is preferable that it have a central body and at least three spokes radially extending from the central body. This can be realized for example as a propeller-like rotor design in which the spokes are designed as paddles arranged in a hydrodynamically advantageous manner in order to effect the desired mixing of the reactor contents and to minimize shear forces affecting the cells in cell cultures within the bioreactor.
In another preferred embodiment, the spokes of the rotor are connected to one another by means of a ring-shaped rim. In this embodiment, the rotor has the form of a spoked wheel in which the actual circulation elements, i.e. the impellers, can also be realized by designing the spokes in a special way.
In both embodiments mentioned, i.e. the rotor designed in the form of a propeller and spoked-wheel, respectively, the circulation elements can also be arranged in the area of the central body. In this case, it would be necessary to design the spokes, to the extent possible, so that they would exert the lowest possible hydrodynamic resistance to the rotation of the rotor.
While with respect to the design of the rotor as a propeller the permanent magnets that interact with the coil arrangement are arranged together with the guide elements designed as sliding blocks or groove elements in the area of the propeller blade tips, it is preferred, in the case of the rotor being designed as a spoked-wheel, that a plurality of permanent magnets be arranged around the circumference of the rim. Depending on the embodiment, the rim itself can serve as a ring-shaped guide shoe. Alternatively, multiple isolated areas of the rim can be designed as sliding block-like guide shoes while the areas of the rim in between serve only to hold magnets. It is also conceivable that the spokes penetrate the rim radially such that a structure similar to a ship's helm results, where the magnets are located on the rim ring, and the sliding block-like guide shoes or groove elements are located in the area of the spoke tips. The inverse arrangement is also conceivable, in which the magnets are located in the area of the spoke tips while the sections of the rim in between serve as guide elements. This version renders radial guiding more difficult, however.
One skilled in the art will recognize that the motorized drive is preferably implemented in the form of a linear motor with a circular, curved long stator in which the sections of the rotor that bear the magnets or magnet groups can be regarded as sliders connected to one another. By controlling the coil arrangements to produce a rotating magnetic field, such as in the form of a three-phase alternating current, the armatures will move synchronously toward one another along the circular path provided by the guide rail of the profile ring. The mechanical connection of the sliders in the propeller- or spoked wheel-shaped rotor results in rotational motion of the rotor. Of course, it is also possible to create such rotational motion if only a single slider is provided, i.e. only one single rotor area bearing one or more magnets.
Further features and advantages of the invention result from the following specific description and the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 a schematic cross-sectional view of a bioreactor in accordance with the invention.
FIG. 2 a perspective sectional view of the bioreactor in accordance with the invention.
FIG. 3 an enlarged view of a section of FIG. 1 .
FIG. 4 a perspective view of a stirrer in accordance with the invention.
FIG. 5 a top view of the stirrer in FIG. 4 .
FIG. 6 a lateral view of the stirrer in FIG. 4 .
FIG. 7 a perspective view of a segment of a profile ring for housing the stirrer.
FIG. 8 a lateral view of the interior side of the profile ring segment in FIG. 7 .
FIG. 9 a sectional view of the profile ring segment from FIG. 7 along the cutting plane x-x in FIG. 8 .
FIG. 10 a sectional view of the profile ring segment from FIG. 7 along the cutting plane IX-IX in FIG. 8 .
FIG. 11 a perspective view of a coil insert.
FIG. 12 a top view of the coil insert from FIG. 11 .
FIG. 13 a lateral view of the exterior side of the coil insert from FIG. 11 .
FIG. 14 a perspective view of a stirrer arrangement composed of a stirrer, profile ring and coil inserts.
FIG. 15 a schematic view of a possible coil/magnet configuration.
FIG. 16 a schematic view of an alternative coil/magnet configuration.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
FIGS. 1 to 14 illustrate as an example a preferred embodiment of the invention and will be discussed together, unless specific reference is made to a particular figure. FIG. 15 and show, purely schematically and as an example, two possible coil/magnet configurations to implement the motorized drive of a stirrer arrangement in accordance with the invention, especially a stirrer arrangement in accordance with FIGS. 1 to 14 . Identical reference numbers in the figures indicate identical or analogous elements.
FIGS. 1 to 3 show highly schematic views of a bioreactor that has a reactor bag 12 and a stirrer arrangement 14 . The reactor bag 12 has a predominantly flexible bag wall 121 that is made rigid only in the area of the stirrer arrangement 14 by the latter's profile ring 16 , which is made of a rigid, non-magnetic material, e.g. plastic. Preferably, the bag wall 121 is interrupted in the area of the stirrer arrangement 14 and is at least partially replaced by the profile ring 16 . The axial edge areas of the latter can be affixed to the bag wall by gluing or welding, for example. It is irrelevant whether the profile ring 16 is bonded to the interior or to the exterior side of the bag wall 121 . Ultimately, the bag wall 121 and the profile ring 16 together form a sealed container that is made rigid in rib-like fashion only in the area of the profile ring and is otherwise flexible. The exterior side of the profile ring 16 is accessible from the exterior of the bag.
FIGS. 1 to 3 do not show inlets and outlets usually provided on bioreactors; however, one skilled in the art would be able to include them depending on the requirements of a specific individual case. Also not shown is a bag holder serving as a bracket or support structure for hanging or supporting, respectively, the reactor bag 12 , which bag holder can be designed as a bracket frame to place the reactor bag 12 on or as an exoskeleton-like container to accommodate the reactor bag 12 . In the latter case in particular, it is possible to arrange the coil inserts, described in more detail below, in the wall of the exoskeleton container such that they are automatically introduced into the profile ring in their deployment position when the reactor bag 12 is inserted or when the exoskeleton container is closed, respectively.
In addition to the profile ring 16 , the stirrer arrangement comprises a rotor 18 rotatably housed in an axial and radial manner in the profile ring, as well as the coil inserts 20 which, although previously mentioned, are hardly visible in FIGS. 1 to 3 . A stirrer arrangement 14 isolated from the reactor bag 12 is shown in FIG. 14 . Its individual elements are described in more detail below in connection with the remaining figures.
One skilled in the art will easily recognize that the bioreactor 10 in accordance with the invention is not limited to versions with only one stirrer arrangement 14 . Rather, it is possible, especially for very tall bioreactors, to position multiple stirrer arrangements 14 at various axial heights. The flexibility of the bag wall 121 in the area between the stirrer arrangements 14 results in a bellows-like or accordion-like compressibility, which causes the storage space to be very small, even with multiple stirrer arrangements 14 .
FIGS. 4 to 6 show various views of a preferred embodiment of a rotor 18 . The actual stirring function is carried out by the elements in the central area of the rotor 18 . In the embodiment shown, these elements are a central body 181 , which is preferably designed in a flow-optimized form, as shown, which provides especially low hydrodynamic resistance to an axial flow. Propeller-like paddles 182 , which are to be regarded as the actual circulation elements, are molded to the central body 181 . The impellers 182 can be given a special design in accordance with standard hydrodynamic criteria, taking into account the requirements of the individual case, especially taking into account the viscosity of the fluid to be stirred as well as the desired rotations per minute. In the embodiment shown, the stirring structure consisting of the central body 181 and the impellers 182 is arranged in a cage 183 that serves, on the one hand, to stabilize the stirring structure and on the other, to effect the mechanical connection between it and the motorized drive described further below. For this purpose, multiple spokes 184 extending radially are molded onto the cage 183 . These spokes 184 preferably have a flow-optimized profile. What specifically is regarded as favourable depends on the requirements of the individual case. A profile form that offers as little resistance as possible can be chosen; on the other hand, it is also possible to design the spokes 184 similarly to the impellers 182 as effective circulation elements. The spokes 184 connect the cage 183 with a rim ring 185 , which, as described in more detail below, is rotatably housed in the profile ring 16 . The rim ring 185 therefore serves as the guide shoe that runs around the entire circumference. In the embodiment shown, the rim ring 185 also serves to bear a plurality of permanent magnets 186 which are inset within it. Preferably this is done such that the magnets 186 do not project axially above the rim ring. It is preferable for them to be molded inside the plastic material of which the rim ring 185 is made.
In an alternative embodiment that is not shown, a continuous rim ring 185 can be dispensed with. In this embodiment, only the radially outer tips of the spokes 184 are formed as isolated guide shoes; one or more of which can bear the magnets 186 .
FIGS. 7 to 10 show a segment 161 of the profile ring 16 in an especially preferred embodiment. Although in principle it is possible to design the basic structure of the profile ring 16 as a single piece, it has been shown to be advantageous, with regard to the assembly of a reactor bag in accordance with the invention and/or a bioreactor in accordance with the invention, to design the profile ring 16 in the form of multiple, preferably identical profile ring segments 161 .
The basic structure of the profile ring segment 161 consists of a curved plastic profile strip, the inner side of which has a guide groove 162 . The width of this groove correspond to the rim ring 185 of the rotor 18 such that the latter is housed axially and radially with little play in the guide groove 162 . Preferably, the appropriate amount of play is adapted to the intended contents of the reactor. In cell cultures in particular, provision of too little play can result in undesired crushing of cells that get between the rim ring 185 and guide groove 162 . It is therefore preferable that the amount of play be greater than the minimum required to maintain the rotational capacity of the rotor 18 and that groove formation on the rotor 18 be prevented by special rolling bearing elements or slide bearing elements 163 , 164 . Multiple radial bearings 163 and axial bearings 164 are therefore distributed around the circumference of the profile ring in the embodiment shown. In the preferred embodiment, the radial bearings 163 each consist of two rollers housed in radial spring bearings, whose axis of rotation is oriented parallel to the axis of rotation of the rotor 18 . These pairs of rollers housed in spring bearings project radially from the exterior into the guide groove 162 . If at least (preferably exactly) three such radial bearings 163 are provided, the rim ring 185 of the rotor 18 is held elastically in a centered position. The axial bearings 164 are designed as spring-pretensioned roller pairs arranged axially opposite on either side of the guide groove 162 , with radially oriented axes of rotation that center the rim ring 185 of the rotor 18 axially and elastically in the guide groove 162 .
It is clearly apparent in FIGS. 7 and 10 in particular that the profile ring segment 161 has a recess 165 on its outer side. This is flanked axially on both sides by the radial mounting surfaces 166 that serve to fasten the flexible bag wall 121 to the profile ring 16 . In particular, they can serve as contact surfaces for a bonded connection, especially by gluing or welding. In the area of a bearing 163 , 164 , the recess 165 , as is especially evident in FIGS. 9 and 10 , is less deep or is interrupted, respectively. However, the recess 165 is deep enough between the bearings that a radial overlap of the recess 165 and the guide groove 162 results. In other words, the radially outer wall of the guide groove 162 forms an axial mounting surface 167 on which the electric coils can be mounted and positioned there at a minimal distance to the permanent magnets 186 within the rim ring 185 that runs within the guide groove 162 .
FIGS. 11 to 13 show various views of a coil arrangement that is formed to correspond to the recess 165 in the outer side of the profile ring segments 161 . In the embodiment shown, the coil arrangement 20 has coil carrier strips 201 on its axial edges which, when the stirrer arrangement 14 is in the assembled state, abut the axial mounting surfaces 167 of the profile ring segment 161 . The coil carrier strips 201 are interrupted in certain areas to allow room for the axial bearings 164 . In the area of the radial bearings 163 , the coil inserts 20 have apertures 202 that provide the space necessary to accommodate the bearing elements.
The actual coils 203 are only indicated schematically in the figures. Their exact design, orientation and electrical contacting are not shown, however can be realized in detail by one skilled in the art, taking into account the requirements of the individual case. FIGS. 15 and 16 show a highly schematized view of two possible designs for a coil. Of course, one skilled in the art will have to suitably coordinate the specific arrangement of the permanent magnets 186 in relation to the specific structure of the coils 203 . One skilled in the art can also design the coordinated controlling of the coils or coil groups in the manner of a circularly curved linear motor, taking into account known electrical engineering aspects. Purely as an example, the standard orientations of the permanent magnets 186 in radial magnetization, axial magnetization and arrangement in a Halbach array are mentioned, each of which requires corresponding coil arrangements and controls.
Of course, the embodiments discussed in the specific description and shown in the figures are merely illustrative exemplary embodiments of the present invention. In the light of the present disclosure one skilled in the art has a broad spectrum of optional variations available.
LIST OF REFERENCE NUMBERS
10 bioreactor
12 reactor bag
121 bag wall
14 stirrer arrangement
16 profile ring
161 profile ring segment
162 guide groove
163 radial bearing
164 axial bearing
165 recess
166 radial mounting area
167 axial mounting area
18 rotor/stirrer
181 central body
182 impeller
183 cage
184 spoke
185 rim ring
186 permanent magnet
20 coil arrangement
201 coil carrier strip
202 aperture
203 coil | A bioreactor has a reactor bag ( 12 ) with a predominantly flexible bag wall ( 121 ) that has a rigid bearing area. A stirrer arrangement ( 14 ) is in the bearing area and includes rigid profile ring ( 16 ) made of a non-magnetic material and fixed in the bearing area. The stirrer arrangement ( 14 ) also includes a shaftless stirrer ( 18 ) rotatably engaged with the profile ring ( 16 ) and having parts that are permanently magnetic. An electric coil arrangement ( 20 ) is outside the reactor bag ( 12 ) and can produce a rotating magnetic field that interacts with the permanent-magnetic areas of the stirrer ( 18 ) to produce a torque that rotates the stirrer ( 18 ) and circulates the contents of the bag ( 12 ). | 1 |
This is a divisional application of Ser. No. 07/798,891 filed Nov. 27, 1991.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the power supply capability for an information processing apparatus and in particular to a power consumption control system for reducing the power consumption in an information processing apparatus under actual working conditions.
2. Description of the Related Art
Electronic equipment such as word processors and personal computers, which have been miniaturized, are supplied with their necessary power from a built-in battery to provide the equipment with portability and mobility. However, the amount of power stored in the built-in battery is limited. Accordingly, it is necessary to suppress the power consumption of the electronic equipment to assure a practical period of operation time. For this purpose, some electronic devices have the capability to suppress the power consumption by turning off the power to the disk drive apparatus if a new access is not made within a predetermined time period from the last access.
The predetermined monitor time can be preset by the user.
Specifically, the power consumption control systems are disclosed in Japanese Patent Application Laid-Open (KOKAI) Sho 64-66719 and OA Personal Computer, Aug. 1990, pages 45 to 47.
In these systems, reduction of power consumption is achieved by constantly monitoring the entry from a keyboard and sequentially turning off power sources for devices which are not used in an apparatus.
For example, if there has been no key entry for a given period of time (several seconds to several tens of minutes), processing is stopped by firstly stopping the supply of clock to a CPU (micro processor). If there has been no key entry for a further given period of time (several minutes to several tens of minutes), a backlight of a liquid crystal display is turned off. If there has been no key entry for an even further given period of time, the display itself is also turned off.
Reduction of power consumed by the floppy disk drive or the hard disc drive is achieved by monitoring the use of the disk drive by means of an exclusive CPU and automatically stopping a motor for the drive if there has been no access thereto for a given period of time (several seconds).
Many of the CPUs or peripheral devices which are to be controlled use all internal registers including static CMOS transistors.
The reason for this will now be described.
Although the power consumption of the LSI increases in proportion to the frequency of clock supplied to the LSI, there is a lower limit of the frequency of the operative clock even if the clock frequency is lowered to reduce the power consumption in the case of dynamic LSI. If dynamic LSI is operated at a frequency lower than the minimum frequency, the contents in the internal registers are lost so that normal operation cannot be performed. On the other hand, in case of static LSI, the contents of the internal registers are not lost, if the supply of clock is stopped. Accordingly, power consumption of the static LSI can be remarkably reduced by appropriately stopping the clock supply when the clock supply is deemed unnecessary.
The CMOS type LSI has characteristics whereby little current flows therethrough if a clock is not supplied to the LSI even when power is supplied to the LSI. The reduction in power consumption is remarkable when the clock supply is stopped.
In order to easily achieve control of the clock supply to the CPU, many CPUs are provided with a command for stopping the supply of the clock (referred to as a "sleep" command) and with a capability to resume the supply of the clock to the CPU in response to an externally provided interrupt signal.
Since a period of time until the supply of power is turned off is constant irrespective of the operating conditions of the equipment in the prior art, the power consumption is increased due to resuming operation in response to an access immediately after the supply of power is turned off if an inappropriate monitor time is set. This problem is serious particularly in equipment requiring a lot of power for activation such as a disc drive apparatus.
In order to avoid such a problem, it is necessary for the user to change the setting of the monitor time depending upon the condition of use of the disk apparatus. This places too high a burden on the users. Appropriate setting is not easy and optimum reduction in power consumption cannot be achieved.
The above mentioned prior art power saving techniques can achieve a remarkable power saving if the user does not use an information processing apparatus, for example, if there has been not key entry for a given period of time or the disk has not been accessed for a given period of time.
However, presence or absence of a key entry is not inherently related to the conditions of use of the peripheral devices or the CPU. These power saving techniques assume that the whole information processing apparatus is not used if there has been no key entry for a while and merely sequentially restrict the supply of power.
The prior art product assumes that a usual application program will not last for several tens of minutes since the termination of the supply of clock to a CPU is stopped if there has been no key entry for several tens of seconds. This may interrupt the processing of some application programs which use the CPU for a long period of time.
The prior art power saving technique is rarely invoked when application programs such as word processing, communication and table calculation are actually executed while the user carries out key entry. Accordingly, power saving is less when in actual use by the user.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a system for controlling the power consumption, which is capable of reducing the power consumption without lowering the processing speed as viewed by a user when in actual use by the user.
It is another object of the present invention to provide an information processing apparatus, a disk drive apparatus and a power source monitoring apparatus, etc., which are capable of automatically changing the period of time until the supply of power is turned on or off depending upon the operating conditions of the equipment.
Another object of the present invention is to realize a power consumption control method which, when the system for reducing power consumption controls by the characteristics of each type of hardware device, minimizes the change of power consumption control, or an information processing device comprising a power consumption controlling method.
In order to accomplish the above mentioned object, the information processing apparatus of the present invention treats as logical resources groups of components implementing a series of processing steps. The present invention is capable of managing the operating conditions of the resources, by holding information on the corresponding relation between each resource and the components which are related therewith, and on the power control of each component. The system then commences the supply of power to a component if the supply of power to the component is stopped when use of its associated resource is required by a certain processing operation and stops the supply of power to a component if the component related with a resource is not used when use of the resource is terminated.
A given period of time which is predetermined for each of the components is measured and after the lapse of a given period of time, the supply of power to the particular component is stopped.
When the use of the component is re-commenced within the given period of time, the measurement of time is terminated.
A subject to be controlled includes clock and power.
Specifically, the present invention comprises at least one of a first power saving means which supplies and stops clocking and a second power saving means which supplies and stops power.
The first power saving means includes clock supply control means for controlling the supply of clock to individual components of the information processing apparatus; clock supply stopping means for determining whether or not it is possible to stop the clock supply to the component when the component is brought into an unused condition and for instructing the clock supply control means to stop the clock supply to the component if it is determined that it is possible; clock supply commencing means for instructing the clock supply control means to commence the clock supply to a component when the component to which clock supply has been stopped is brought into a used condition; the second power saving means includes power supply control means for controlling supply of power to individual components of the information processing apparatus; power supply stopping means for determining whether or not the power supply to the component can be stopped when the component is brought into an unused condition and for instructing the power supply control means to stop power supply to the component if it is determined that power stoppage is possible; and power supply commencing means for instructing the power supply control means to commence the power supply to a component when the component, which has had its power supply, is brought into a used condition.
In addition to the clock supply control means for controlling supply of clock to each component of the information processing apparatus, clock switching means for switching the clock frequency to a normal operating value or a value lower than the normal operating value may be provided.
In this case, the clock supply stopping means determines whether or not stopping the clock supply to the component is possible when the component is brought into an unused condition and instructs the clock supply control means to stop the clock supply to the component if it is determined that this is possible, and instructs the clock switching means to switch the clock frequency into the value lower than the normal operating value when the clock supply must be maintained.
The clock supply commencing means instructs the clock supply control means to commence the clock supply to a component when a component which has had its clock supply stopped is brought into a used condition, and instructs the clock switching means to recover the clock frequency to the normal operating value when a component which has had its clock frequency lowered is brought into a used condition.
The first power saving means includes clock supply control means for controlling clock supply to individual components of the information processing-apparatus; clock supply stopping means which determines whether or not the clock supply to a component can be stopped immediately and has the capability to instruct the clock supply control means to stop the clock supply to the component if immediate stopping of the clock supply to the component is possible and a capability to instruct the clock supply control means to stop the clock supply to the component when the component remains in an unused condition for a certain period of time, which is predetermined for each component, if immediate stopping of the clock supply is impossible; and clock supply commencing means for instructing the clock supply control means to commence the clock supply to a component which has had its clock supply stopped when it is brought into a used condition.
The second power saving means includes power supply control means for controlling supply of power to individual components of the information processing apparatus; power supply stopping means which determines whether or not the power supply to a component can be immediately stopped and has the capability to instruct the power supply control means to stop the power supply to the component if the component has been in an unused condition for a period of time which is predetermined for each component if immediate stopping of the power supply is impossible; and power supply commencing means for instructing the power supply control means to commence the power supply to a component when the component which has had its power supply stopped is brought into a used condition.
The power consumption of components (hardware devices) can be controlled by the above-mentioned structure.
On the other hand, in order to control the power consumption of a CPU, the present invention provides the CPU with clock input stopping means for stopping input of clock from the clock supply control means when there is no processing to be executed and clock input commencing means for commencing the clock input from the clock supply control means when an interrupt is externally generated.
If a plurality of components are incorporated into a composite device, clock and power cannot be supplied or stopped for each of the components. Accordingly, in this case, the composite device is provided with clock supply control means for controlling supply and stop of clock to each component in response to an external instruction. Specifically, the clock control means is a switch and is formed on the same semiconductor chip as the components.
Now, operation of the invention in the above-mentioned aspects will be specifically described.
Since there are a plurality of components related with one resource in an information processing apparatus which treats as logical resources groups of components implementing a series of processing operations, a resource device management table for holding the corresponding relationship between each resource and the components related therewith and a device management table for holding information on power control of each component are implemented.
The device management table holds a "clock status" representative of whether or not clock is supplied to each component, a "power status" representative of whether or not power is supplied to each component; a "clock stop flag" representative of whether or not the clock supply to each component can be stopped when the component is brought into an unused condition, a "power stop flag" representative of whether or not the power supply to each component can be stopped when the component is brought into an unused condition, a "time-out flag" representative of whether or not immediate stop of the clock or power supply to each component is possible when the component is brought into an unused condition; a "time-out period" representative of the value of a given period of time until clock or power supply to each component is stopped if immediate stopping of clock or power supply to the component is impossible.
When use of the resource is commenced by certain processing operations, components which are related with the resource are determined from the resource management table. If it is found with reference to the clock status and power status of the device management table that clock or power is not supplied to each of the determined components, supply is commenced. When the use of the resource is terminated, components related with the resource are determined from the resource device management table. If the determined components are not used, supply of clock or power thereto is stopped as follows. If there are other resources which commonly use the determined component, supply of clock or power is stopped after it is confirmed that all the resources are not in use.
If it is determined from the clock stop flag, the power stop flag and the time-out flag that immediate stopping of clock or power is possible, supply of clock or power is stopped.
If immediate stopping of clock or power supply is not possible, supply of clock or power is stopped after the lapse of a predetermined time period.
Thus, the supply of clock or power is stopped when the component related with the resource is brought into an unused condition. The supply of clock or power is resumed when the resource is used again. Accordingly, power is supplied for the minimum period of time necessary for operation of each unit of hardware. The power consumption during operation can thus be suppressed to the minimum.
Since a power saving method which is appropriate for each hardware device is achieved in accordance with the "clock stop flag", "power stop flag", "time-out flag" and "time-out period", this invention is applicable to hardware devices having various characteristics.
Input of the supplied clock to a CPU is stopped when there is no processing to be executed. Input of the supplied clock to the CPU is resumed when an interrupt is externally generated.
This can suppress the power consumption of the CPU, which is highest, to the minimum.
Since input of clock is immediately resumed when a processing operation, which the CPU should execute, is generated in response to an external interrupt, the speed of execution in the information processing apparatus is not lowered.
The present invention has a construction that separately provides a hardware device non-dependent section which determines if each resource is in use or not and a hardware device dependent section which instructs execution and termination of the power consumption means according to the characteristics of the device corresponding to each hardware group comprising each resource. Due to the construction of the present invention, the change of the power consumption control can be minimized by changing the hardware dependent section, even when the method for reducing power consumption differs according to the characteristics of each type of hardware device.
In a second aspect of the present invention, there is provided an information processing apparatus including means for detecting the operating conditions of a device; means for switching on or off the supply of power to the device; means for measuring time; and control means for controlling the switching means to switch off the supply of power to the device if the control means confirms, based upon a detected result of the detecting means and an input from the time measuring means, that the device has been in a predetermined condition for a preset monitor time. The control means also controls the switching means to switch on the supply of power to the device when the control means confirms, based upon the result of detection of the detecting means, that the device has been taken out of the predetermined condition. The control means is characterized in that it changes the preset value of the monitor time based upon the detected result of the detecting means.
It is preferable that the control means has maximum and minimum monitor times which are upper and lower limits of the monitor times and changes the monitor time within this range.
It is preferable that the control means has a reference monitor time which is used as a reference of the monitor time, compares an interval from when the power is turned off until the power is turned on with the reference monitor time and extends and shortens the monitor time if the reference monitor time is longer or shorter, respectively.
In a further aspect of the present invention, there is provided a power monitoring apparatus including means for detecting the operating conditions of a device; means for switching on or off the supply of power to the device; means for measuring time; and control means for controlling the switching means to switch off the supply of power to the device if the control means confirms based upon a detected result of the detecting means and an input from the time measuring means, that the device has been in a predetermined condition for a preset monitor time. It also controls the switching means to switch on the supply of power to the device when the control means confirms based upon the detected result of the detecting means that the device has been taken out of the predetermined condition. The control means is characterized in that it changes the preset value of the monitor time based upon the detected result of the detecting means.
There is also provided a disc drive apparatus.
Operation of the second aspect will be described.
The control means detects the operating conditions of the equipment by means of detecting means and controls the switching means to turn off the power to the equipment on a given condition of the equipment, for example, a condition that the disk drive apparatus has not been accessed during the monitor time or longer. The control means turns on the power if the disk drive apparatus is accessed while it is in this aforementioned condition. At this time, the control means measures the period of time from turning off until turning on.
The control means shortens the monitor time by a given period of time if the measured period of time is longer than the monitor time. That is, the period of time until the power is turned off is shortened. The control means extends the monitor time by a given period of time if the measured period of time is shorter than the monitor time. That is, the control means extends the period of time until the power is turned off. The monitor time is changed within a range between the maximum and the minimum monitor times. If the monitor time does not fall within this range, the monitor time is set to the minimum or maximum monitor time.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1(a) to (e) are flow charts showing the processing steps of a power consumption control system which is an embodiment of the present invention;
FIG. 2 is a block diagram showing the hardware configuration of an information processing apparatus to which the power consumption control system of the present embodiment is applied;
FIG. 3 is a block diagram showing a software configuration in the present embodiment;
FIG. 4 is a chart explaining the operation of a multi-task OS;
FIGS. 5(a) to (c) are flow charts showing the processing structure, queue and table structure of the multi-task OS;
FIGS. 6(a) to 6(d) are flow charts showing the task control processing and the input/output control processing of the multitask OS;
FIGS. 7(a) and 7(b) are schematic tables showing the structure of tables in the present embodiment;
FIG. 8 is a block diagram showing the operation of power control processing;
FIG. 9 is a block diagram showing the data structure;
FIG. 10 is a flow chart showing power control processing steps;
FIG. 11 is a flow chart showing the steps of recalculation processing during monitor time; and
FIG. 12 is a block diagram showing the structure of another embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
An embodiment of the present invention will be described with reference to the drawings.
The configuration of an information processing system to which an embodiment of a power consumption control system of the present invention is applied will be described with reference to FIG. 2.
In the drawing, a reference numeral 1 denotes a central processing unit (CPU); 2 a main memory (MM); 3 a clock generator (CG); 4 a direct memory access controller (DMAC); 5 a power controller; 6 a video memory (VRAM); 7 a liquid crystal display controller (LCDC); 8 a liquid crystal display (LCD); 9 a backlight (BL); 10 a floppy disk controller (FDC); 11 a floppy disk driver(FDD); 12 a communication controller (SCC1); 13 a keyboard (KB); 14 a communication controller (SCC2); 15 a modem unit (MU); 16 a communication controller (SCC3); 17 an image scanner (IS); 18 a printer controller (PRC); 19 a printer; 20 a main bus (MB); 21 a power unit (PU); and 22 a timer (TIM).
In FIG. 2, CPU 1 successively interprets programs stored in MM 2 for controlling each peripheral device and for executing processing. CPU 1 has a sleep command and a capability to resume processing by an interrupt and is capable of stopping/resuming the clock supplied from CG3 by itself.
The DMAC 4 is an LSI for performing high speed data transfer between MM 2 and each of the peripheral devices without transferring through the CPU 1. PC 5 controls supply of clock and power to each of peripheral devices. Specifically, it has the capability of individually turning on or off clock switches 40 to 48 and switches 31 to 34 for the PU 21.
The VRAM 6 stores the display content of each dot on the LCD 8. The LCDC 7 periodically reads out the contents of the VRAM 6 for displaying them on the LCD 8. The BL 9 illuminates the LCD 8 from the rear side thereof to provide an easily visible display.
The FDC 10 controls the FDD 11 to read/write to and from the floppy disk.
The SCC1 12 controls the KB 13 to accept information on key entry. The SCC2 14 controls the MU 15 for performing data communication via the public network to perform communication processing. The SCC3 16 controls the IS 17 to perform processing for accepting image data.
The PRC 18 controls the PRT 19 to perform a printing operation. TIM 22 is used for time measuring and generates an interrupt for the CPU 1 at regular intervals.
These peripheral devices are coupled with each other via the MB 20 and exchange data with each other via MB 20.
PU 21 supplies power to all devices except for the IS 17 and the PRT 19 which are housed in separate casings and have their own power sources. In the present embodiment, only the power of the BL 9, LCD 8, FDD 11 and MU 15 can be turned on or off.
The configuration of software operated on the foregoing hardware will be described with reference to FIG. 3.
In FIG. 3, an operating system (OS) 62 has common capabilities which are necessary to operate the users' jobs. A program which is operated on the OS 62 to achieve the users' jobs is referred to as "Task" 60.
The OS 62 has a multi-task capability to execute a plurality of tasks 60 in parallel. Each of tasks 60 controls processing of the CPU 1 and each input/output device to perform a desired function.
The OS 62 manages hardware devices which are necessary for tasks 60 to operate in the concept of "logically abstracted resource" so that the tasks 60 can easily operate the hardware devices.
For example, the OS 62 collectively treats hardware devices such as the FDC 10, DMAC 4, FDD 11, and floppy disks loaded in the FDD 11 as resource type "floppy disk" and treats the VRAM 6, LCDC 7, LCD 8 as resource type "display". This enables the tasks 60 to use the function of each hardware device without recognizing physical control of hardware.
The OS 62 has functional blocks as follows:
(1) A task management block 63 for managing the operating state of the task 60 operated on the OS 62 and for controlling so as to sequentially allocate a CPU resource to each of the tasks 60.
(2) A memory management block 64 for allocating a memory resource to the program and data of each of the tasks 60 and for locating it on the MM 2 and for managing the usage condition of the memory.
(3) An input/output management block 65 for managing the usage condition of each input/output resource and to sequentially allocate each input/output resource to each of the tasks 60.
(4) A timer management block 66 for managing a processing condition for time monitoring and for executing a predetermined processing when a preset time has lapsed.
(5) A system management block 67 for initializing the OS 62 and for performing error processing.
Blocks for performing physically dependant controls of input/output resources are referred to as physical device drivers. A physical device driver is provided for each input/output resource. Input/output processing of the resources is achieved by controlling these physical drivers by means of the input/output management block 65.
In the present embodiment, the physical device drivers include a floppy disk driver 68, a keyboard driver 69, a communication driver 70, an image scanner driver 71, a printer driver 72 a display driver 73.
If a device is newly added, an additional physical device driver for this added device is prepared and registered in the OS 62. This enables the added device to be used as a resource by the tasks 60.
Means for calling the foregoing functional blocks of the OS 62 from the tasks 60 is referred to as supervisor call (SVC)60.
How the tasks 60 and input/output resources are generally operated by the OS 62 will be described with reference to FIG. 4.
In this case, it is assumed that a Task A and a Task B will be operated on in parallel and that the priorities of the tasks will be the same.
FIG. 4 is a time chart showing the processing content of each task with the lapse of time.
If the tasks are executed in order of the Tasks A and B, the CPU processing 85 of the task A is commenced in the order in which they arrive. If the task A begins floppy disk input/output processing 86, the OS 62 allocates an empty CPU resource 85 to the task and commences the CPU processing 85 of the task B since the CPU resource is not necessary during this processing.
If the task B issues a floppy disk input/output request to the OS 62 before the floppy disk input/output processing 86 of the task A is completed, the OS 62 performs a control so that the floppy disk input/output processing 86 of the task B is put into a wait state, as represented by a dotted line 90, until the floppy disk input/output processing 86 of the task A is completed since only one task can be used for one resource.
Thereafter, the task B repeats the floppy disk input/output processing 86 and the CPU processing 85 while the task A performs the keyboard input processing 87 after executing the CPU processing 85. Since no conflicts of use among tasks occurs during this processing, two tasks operate in parallel.
If the keyboard input processing 87 is then completed, the task A will try to execute the CPU processing 85. However, the task A waits for execution of the CPU processing 85, as represented by a dotted line 91, since the task B is executing the CPU processing 85.
A chart showing the usage conditions of each resource is shown in FIG. 4. It is further found from FIG. 4 that resources such as the CPU, floppy disk and keyboard are not always used and conditions which are not used by any tasks frequently occur as represented by dotted line 92.
Generally, a plurality of tasks are rarely operated in parallel in an information processing system such as a word processor which performs processing in response to an input from an user. Since processing is executed while sequentially using each resource when user's editing operation is performed, the activity ratio of each resource in an actual use condition is considerably lower than that shown in FIG. 4.
As mentioned above, the multi-task OS manages each hardware device according to a concept resource. A condition in which each resource is not used exists in the situation in which tasks are actually operated.
The power which is consumed by hardware devices constituting the resources is very high in the situation where the resources are not used. If the power consumed in the unused condition can be reduced, it becomes possible to reduce the total consumed power without lowering the processing speed of a computer system.
A power consumption management system provided in the OS 62 of the present embodiment will be described. First though, operation of the OS 62 which is necessary in explaining the management system will be described.
FIGS. 5(a) to 5(c) show the program configuration of the OS 62 for achieving the input/output control of the task 60 and the configurations of queues and tables used for the input/output control of the task 60. FIG. 6(a) to 6(c) show the flow chart of the processing.
In FIG. 5(c), a task management table 110 is a table for managing the condition of the task 60 operated on by the OS 62. The task management table 110 includes as fields, a link pointer 111 pointing to another task management table 110, the priority 112 of the tasks 60, task state 113 representative of whether the task 60 is executing or waiting for input/output and memory occupation information 114 representative of where in the MM 2 the program of the task 60 is to be placed.
An input/output request management table 120 manages the input/output processing condition which is requested by the task 60 and includes as fields, a link pointer 121 pointing to other input/output request management tables 120, a pointer 122 pointing to the task management table 110 of the task 60 which is executing an input/output request, a priority 123 of the task 60, and an input/output request parameter 124 representative of the contents of the input/output processing.
A timer management table 130 has control information of a timer which is used when processing is desired to be executed after a given period of time and includes as fields, a link pointer 131 pointing to another timer management table 130, a measuring time 132 for which the residual time until time out is held, a time out processing address 133 representing a processing program which is executed at time out, and a device number 134 representative of which hardware device the timer is designated for.
In FIG. 5(b), the CPU queue 103 links the task management tables 110 from the head pointer 106 via the link pointer 111 and manages the order of the tasks 60 for allocating the CPU resources.
An input/output queue 104 is provided for each input/output resource and links the input/output request management table 120 from the header pointer 107 via the link pointer 121.
Since each input/output request management table 120 manages to show which task the input/output is requested from, it links the task management tables 110 via the pointer 122 pointing the task management tables 110. The input/output queue 104 manages the order of allocation of each input/output resource to the tasks 60.
A timer termination queue 105 links the timer management table 130 from the header printer 108 via the link pointer 131 and manages respective states of the preset timers.
As shown in FIG. 5(a), when the task 60 issues the SVC 61, the OS 62 executes SVC processing 100. When an interrupt 136 is issued from an input/output device 135, the OS 62 executes interrupt processing 101.
When the task 60 issues SVC 61 for generating and activating another task 60, the OS 62 executes SVC processing shown in the flow chart of FIG. 6(a) as the SVC processing 100.
In the SVC processing 1000, the task management tables 110 of the specified programs are prepared in step 1010 and the prepared task management tables 110 are connected with the CPU queue 103 in step 1020.
At this time, the task management tables 110 are arranged in accordance with the task priority 112 and arranged in order from previously activated tables if the priority is the same.
When the activated task 60 issues SVC 61 representative of the termination of itself, the OS 62 executes SVC processing 1100 shown in the flow chart of FIG. 6(b) as the SVC processing 100.
In the SVC processing 1100, the task management table 110 of the task 60 is removed from the CPU queue 103 in step 1110 and is omitted in step 1120.
When the activated task 60 issues SVC 61 for executing an input/output request of a resource, the OS 62 executes SVC processing 1200 shown in the flow chart of FIG. 6(c) as SVC processing 100.
In the SVC processing 1200, the input/output request management tables 120 of the specified resources are prepared in step 1210 and the input/output request management tables 120 are connected to the input/output queues 104 of the resources which will be objects. At this time, the tables are arranged in order of priority similarly to the CPU queue 103.
Then, the task management table 110 of the task 60 which executes the input/output request is removed from the CPU queue 103 in step 1230 and is connected with the pointer 122 pointing to the task management table 110 in the prepared input/output request management table 120 in step 1230.
Finally, an input/output processing is commenced by controlling actual hardware devices in step 1240. When the input/output processing of the resource is completed, an interrupt 136 is generated from the input/output device 135 and the OS 62 executes interrupt processing 1300 shown in the flow chart of FIG. 6(d) as the interrupt processing 101.
In the interrupt processing 1300, devices which are related with the input/output and require initialization are initialized without hindering the other input/output requests in step 1310. The input/output request management table 120 of the input/output resource, the processing of which is completed is removed from the input/output queue 104 and returned to the CPU queue 103 in step 1320 and the input/output request management table 120 is omitted in step 1330.
After the SVC processing 100 and the interruption processing 101 have been performed in such a manner, a processing which is referred to as "dispatcher 102" shown in FIG. 5(a) is called.
In the dispatcher 102, the processing of the task 60 which is represented by the leading task management table 110-1 is resumed by looking at the CPU queue 103. If there is no task management table 110 in the CPU queue 103, the program is brought into an idling state and is looped in the dispatcher 102.
If the task 60 requests an input/output by the foregoing processing, the task management table 110 is removed form the CPU queue 103 and the execution of the CPU processing is waited for until the input or output is completed.
Determination as to whether or not the resource is used can be made by merely looking at whether each input/output queue 104 or the CPU queue 103 is empty by performing such a control within the OS 62.
Now, power consumption control processing which is performed by using such a resource management of the OS 62 will be described.
Referring now to FIGS. 7 and 1, there are shown the configuration of the table provided for the power consumption control and the flow of actual processing, respectively.
A resource device management table 140 is provided as shown in FIG. 7(a).
The resource device management table 140 comprises a two dimensional array including resource numbers 141 each uniquely representative of a resource on the OS 62 and device numbers 142 each uniquely representative of a hardware device which individually performs an operation. Each element in the array has a flag representative of whether or not each device is involved in the operation for a resource.
For example, the DMAC of #0, FDC of #5, and FDD of #6 are used for the input/output processing of the floppy disc resource of #0.
In this table, a device number 142 is given to objects to which supply of clock and power are controlled.
A device management table 150 is provided corresponding to each hardware device to which the device number 142 is allocated as shown in FIG. 7(b).
These hardware devices are classified into two groups in view of power consumption control.
The first group comprises LSIs such as the DMAC 4, the VRAM 6 and FDC 10 which require power supply for holding internal chip states and whose power consumption can be considerably reduced by stopping the supply of clock and devices such as the FDD 11, BL 9 and MU 15, the power consumption of which can be reduced merely by turning off the power supply.
The field of clock stop flag 151 and power supply stop flag 152 control these devices. Respective flags represent whether or not the clock or the power source may be turned off when the hardware is not used. The values "0" and "1" represents "no permission" and "permission", respectively.
On the other hand, the second group comprises devices such as the CPU 1 and peripheral LSIs, the clock or the power source of which may be turned off immediately if the hardware device is not used, devices such as the FDD 11 which may consume a lot of power upon reactivation if it is frequently turned off, and devices such as the LCDC 7, LCD 8 and BL 9, the clock or the power source should be turned off after confirming that they will not be used for a given period time, the reason for this being that the power source cannot be immediately turned off even if the device is not used as a resource since the display becomes invisible when the power is turned off.
The field of time out flag 153 and time-out period 154 control these devices.
The time-out flag 153 represents whether or not the power source may be turned off when the device is not used. The values "0" and "1" represent "permission" and "no permission", respectively.
The time-out period 154 is valid only when the time-out flag 153 is "1" and has for each device a value which defines a period of time for no use of the device after which the power source may be turned off.
A clock status 155 and a power source status 156 hold a status representative of whether or not the clock and the power are supplied to each device. The states "0" and "1" represent "not supplied" and "supplied", respectively.
Power consumption control processing which is performed in accordance with such table will be described with reference to FIG. 1.
The power on processing 200 for a resource shown in the flow chart of FIG. 1(a) is added between steps 1230 and 1240 in the resource input/output commencement processing 1200 (FIG. 6(c)) which is performed as the SVC processing 100 of FIG. 5.
In step 210, the hardware used by the input/output resource to which an access is requested is determined by searching a device having a value "1" in the resource device management table 140.
Processing of steps 220 to 310 is repeated for each determined device.
That is, the time-out flag 153 of the device is checked in step 220.
If the time-out flag 153 is "1", the power or clock is turned off for saving power only when the device has not been used for a given period of time in the present embodiment. To this end, the timer is preset to a measuring time when the use of the resource is terminated. If the use of the resource is resumed before the preset timeout has elapsed, the timer is cancelled.
In other words, the timer management table 130 having a device number 134 of a device involved in the resource to which an access is requested is searched for in the timer termination queue 105 in step 230. If found, the timer management table 130 is omitted from the timer termination queue 105 in order to stop timer measurement in step 240.
If the clock status 155 is "0" representing "not supplied" in step 250, the status 155 is changed into "1" representing "supplied" in step 260. The supply of clock to an object device is commenced via the PC 5 in step 270.
If a power source status 156 is "0" representing "not supplied" in step 280, the status is changed into "1" representing "supplied" in step 290. Supply of power to an object device is commenced via PC 5 in step 300.
Normal operation of the hardware devices are assured by performing processing shown in step 1240 of FIG. 6(c) after the above mentioned processing has been performed for all devices involved with the resources to be accessed in step 310.
Resource power off processing 400 shown in the flow chart of FIG. 1(b) is performed immediately after the completion of input/output processing 1300 (FIG.6(d)) performed as the interruption processing 101 of FIG. 5.
A device which is involved with the resource, an access to which is completed, is determined by searching for a device in which the value of the resource device management table 140 is "1" in step 410 after the input/output request management table 130, an access to which is completed, is omitted by the input/output completion processing 1300.
Processing of steps 420 to 510 is repeated for each determined device.
In other words, determination of whether or not there are other resources involved with the device is made with reference to the resource device management table 140 in step 420. If there are any resources, whether or not all the input/output queues 104 of the resources involved with the device are empty is checked.
If there is no resource which is being processed in step 420, the time out flag 153 is then checked in step 430. If the flag is "1", the timer management table 130 is generated and is connected with the timer completion queue 105 to commence time measuring in step 440 since the power source and clock should be turned off if there is no access for a given period of time after completion of the access.
At this time, a value of the timeout 154 of the device management table 150 is initially set to the measuring time 132 of the timer management table 130. An execution address of the timeout processing prepared depending upon each device is set to the time out processing address 133. The number of the device which completes the processing is set to the device number 134.
On the other hand, if the timeout flag 153 is "0" in step 430, the clock stop flag 151 is then checked in step 450. If the flag is "1" (stop is possible), the value of the clock status 155 is then changed into "0" (not supplied) in step 460. Supply of clock to an object device is stopped via the PC 5 in step 470.
The power source stop flag 152 is also similarly checked in step 480. If the flag is "1" (stop is permitted), the value of the power source status 156 is then changed to "0" (not supplied) in step 490. Supply of power to an object device is stopped via the PC 5 in step 500.
After the devices which have not been used are all checked when input/output is completed by the above mentioned processing (step 510), the power and clock can be immediately stopped.
The relationship between the device and the resource is managed by the resource device management table 140 so that determination as to whether or not a device, such as the DMAC 4, which is used by a plurality of resources is being used can be easily made by checking all the states of the input/output queues 104 of corresponding resource.
A device which has its power source or clock turned off if the time-out flag 153 is "1", that is, a device which is not used for a given period of time, will be described.
When a timer is set in step 440 in the resource power off processing 400 shown in the flow chart of FIG. 1(b), timer interrupt processing 600 shown in the flow chart of FIG. 1(c) is generated periodically.
In the timer interrupt processing 600, processing is performed for each timer management table 130 of the timer termination queue 105 as follows:
The time of the timer interrupt period is subtracted from the measured time 620 in step 610. When thus subtracted time becomes "0" or less, that is, the time which has been initially set in the timer management table 130 has lapsed, the time-out processing 700 which the time-out processing address 133 addresses is executed in step 620.
As shown in the flow chart of FIG. 1(d), in the time-out processing 700, the timer management table 130 in which time-out occurs is removed from the timer termination queue 105 in step 710. If the clock stop flag 151 is "1" (stopping is permitted) in step 720, the value of the clock status 155 is changed into "0" (not supplied) in step 730 and supply of clock to an object device is stopped.
If the power source stop flag 152 is "1" (stopping is permitted) in step 750, the value of the power source status 156 is changed into "0" (not supplied) is step 760. Supply of power to an object device is stopped in step 770.
Power saving is achieved by stopping the supply of power or clock to the device in accordance with the above mentioned processing when the device has not been used for a period of time which was preset in the time-out period 154 of the device management table 150 for each device.
Supply of power or clock is resumed at the time when input/output of the resource which is involved with the device is commenced as shown in the flow chart of FIG. 1(a).
Now, a power consumption control processing 800 for the CPU resource will be described with reference to the flow chart of FIG. 1(e).
This processing is executed in the dispatcher 102 in FIG. 5.
The dispatcher 102 has heretofore functioned to resume the execution of the task 60 corresponding to the task management table 110-1 with reference to the leading task management table 110-1 of the CPU queue 103 (corresponding to step 820). When there is no task management table 110 in the CPU queue 103, that is, there is no task which is to execute the CPU processing, the CPU is brought into an idle state and only repeats a loop in the dispatcher.
In contrast to this, a CPU sleep command is issued as shown in step 830 in the present embodiment when the CPU is brought into an idle sate. Accordingly, wasteful power consumption due to the idle state of the CPU is prevented by stopping clock of the CPU per se.
Since supply of the clock to the stopped CPU 1 is immediately resumed on execution of interrupt processing, when an interrupt is externally generated, control of peripheral hardware devices is not obstructed.
When the interrupt processing is completed, the processing of the dispatcher 102 is returned to step 810 to complete the input/output by the interrupt processing. If the task management table 110 is connected with the CPU queue 103, the task 60 is then executed. If not connected, the sleep command is continuously issued.
The power consumption of each device, to which the supply of the power or clock can be turned on or of in real time, can be reduced without lowering the execution speed by immediately stopping the supply of the power or clock thereto when the device is brought into an unused condition in the present embodiment as mentioned above.
Power saving of the device, supply of power and clock to which cannot be turn on or off in real time can be also achieved by using the time management block 66 of the OS 62 if the device has not been used for a given period of time.
In such a manner, supply of power and/or clock to the device which is not related with the processing which an user executes can be stopped at any time even when the user actually uses an information processing system. As a result, the power consumption of the whole of the information processing system can be suppressed to the minimum without having a detrimental effect on the processing speed.
A remarkable power saving effect can be obtained, in particular, in the wordprocessor or personal computer in which one operation is sequentially executed in response to each key entry from the user so that the activity factor of the CPU 1 or each of the peripheral devices is often only between several and tens or percentages.
Although the above embodiment has been described with reference to a case in which peripheral LSIs are static C-MOS devices, a similar effect can be obtained by providing the PC 5 with the capability of changing the clock frequency to the minimum operative value in lieu of stopping supply of clock to dynamic type LSI devices in which supply of clock cannot be stopped and by performing a control similarly to the above embodiment.
Although power consumption is suppressed by controlling the supply of clock to each LSI in the above mentioned embodiment, various capabilities which have been heretofore separately achieved by individual LSIs could have been incorporated into one LSI due to the recent advance in high integration of LSIs. It is hard to achieve an effective power saving by controlling supply of clock to such an LSI.
The power consumption of an LSI having a CPU, DMAC and SCC thereon can be suppressed by stopping supply of clock thereto only when the CPU, DMA and SCC are not simultaneously used.
In order to overcome this difficulty, an approach is proposed wherein a switch which individually controls the supply of clock is provided for each component in a LSI chip so that the switch is turned on or off in response to an external signal to the LSI. Such a switch can be easily formed from conventional semiconductor devices.
Sophisticated power consumption control can be also achieved depending upon the usage conditions of resources in highly integrated LSIs having various capabilities by adopting the above mentioned approach.
Another embodiment of the present invention will be described with reference to drawings.
Referring now to FIG. 8, there is shown a block diagram of the structure of an information processing system.
The information processing unit comprises a CPU 7001, a disk controller 7003, a disk drive 7004, a control unit 7005, a timer 7010, and a power control 7020.
The CPU 1 7001 performs processing of various data and controls the operation of the disk drive 7004 via the disk controller 7003.
The disk drive 7004 has the capability of storing various data. The power to the disk drive 7004 can be switched on or off by the control unit 7005. Although the disk drive 7004 is a floppy disk drive in the present embodiment, the disk drive 7004 is not limited to this and may be a device other than a disk drive.
The power control 7020 is periodically activated in response to an input from the timer 7010. When the power control 7020 is activated, it monitors an access request from the disk controller 7003 to the disk drive 7004 and detects the operating condition of the controller and has the capability of controlling the control unit 7005 in response to a detection result and information on the lapsed period of time which is input from the timer 7010. The control unit 7005 has the capability of turning on or off the power to the disk drive 7004 in response to an instruction from the power control 7020. The power control 7020 of the present embodiment has the capability of more effectively suppressing the consumed power by dynamically changing the period of time until the power to the disk drive 7004 is turned off depending the condition of access to the disk drive 7004.
The power control 7020 is not separately provided, but is implemented in a program stored in the CPU 7001 of the information processing system.
The configuration of data which the power control 7020 uses therein is shown in FIG. 9.
The data comprises three fields such as mode identification data 7201, a count value 7202 and a monitor time value 7203.
The mode identification data 7201 represents which of a time measuring mode and a monitor mode, the power control 7020 is operating in.
The time measuring mode is a condition in which the power supply to the disk drive 7004 is turned off and the lapsed period of time (hereinafter referred to as OFF time) since the power supply is turned off is measured.
The monitor mode is a condition in which the power supply to the disk drive 7004 is turned on.
The count value 7202 is a reversible counter which in the time measuring mode is used as an up counter for counting the off time of the disk drive 7004 and in the monitoring mode is used as a down counter for indicating the remaining monitor time, that is, the remaining period of time until supply of power to the disk drive 7004 is turned off.
The monitor time 7203 indicates a lapsed period of time (hereinafter referred to as monitor time) until the supply of power to the disk drive 7004 is turned off after the disk drive is last accessed.
Although not shown in the drawings, other data such as a reference monitor time value which will be a reference of the monitor time, a maximum monitor time value which is a maximum value of the monitor time, a minimum monitor time value which is a minimum value of the monitor time, monitor time incremental or decremental value which is an increment or decrement by which the monitor time is increased or decreased respectively are provided.
Operation will now be described.
FIG. 10 is a flow chart showing the operation of the power control 7020.
The power control 7020 is activated by the periodic interrupt from the timer 7010 (step 2000). If activated, the power control 7020 then checks the mode identification data 7201 to determine what the current operation mode is (step 2001). If the mode is the time measuring mode, the program will proceed to step 2002. Conversely, if the mode is the monitor mode, the program will proceed to step 2012.
In step 2002, the power control 7020 determines whether or not there was an access request form the disk controller 7003 to the disk drive 7004 during the time between the present time and the previous activation.
If there was no access, the count value 7202 is then incremented by one (step 2007) to terminate the processing (step 2020). Conversely, if there was an access, the control unit 7005 is controlled to turn on the power supply to the disk drive 7004 (step 2003). Subsequently, the monitor time recalculation processing is performed (step 2004). The monitor time recalculation processing will be described hereafter in detail.
After the monitor time recalculation processing, the power control 7020 presets the monitor time value 7203 based upon a value calculated by the monitor time recalculation processing and replaces the count value 7202 with the monitor time value 7203 (step 2005). Thereafter, the power control 7020 changes the mode identification data 7201 into the monitor mode (step 2006) to terminate the processing (step 2020).
If the mode is the monitor mode in step 2001, the program step will proceed to step 2012.
The power control 7020 determines whether or not there was an access request from the disk controller 7003 to the disk drive 7004 in the interval between the previous activation and the present time. If there was an access request, the power control replaces the count value 7202 with the monitor time value 7203 to initialize the count value 7202 (step 2017), and thereafter terminates the processing (step 2020).
If there was no access request, the power control decrements the count value 7202 by one (step 2013) and determines whether or not the count value 7202 is 0 (step 2014). If the count value 7202 is not 0, the program step will proceed to step 2020 and terminates the processing (step 2020). If the count value 7202 is 0, the power control controls the control unit 7005 to turn off the power supply to the disk drive 7004 (step 2015). The power control changes the content of the mode identification data 7201 into the time measuring mode from the monitor mode (step 2016) and then terminates the processing (step 2020).
The above mentioned monitor time recalculation processing which is performed in step 2004 will be described with reference to FIG. 11.
The value which is represented by the count value 7202 at the time when the recalculation processing is performed is representative of the off time of the disk drive 7004, that is, the lapsed period of time until the present time since the supply of power to the disk drive 7004 is turned off.
Accordingly, after commencement of operation (step 2050), the power control 7020 compares the current count value 7202 with the reference monitor time value in step 2051. If the count value 7202 is larger than the monitor time value, the program step will proceed to step 2052. If smaller, the program step will proceed to step 2062.
The power control 7020 determines that the frequency of access to the disk drive 7004 is decreased since the count value 7202, that is, the off time is larger than the reference monitor time and decreases the monitor time value 7203 by the decreased value (step 2062). This shortens the monitor time so that the period of time until the supply of power to the disk drive 7004 is turned off is shortened.
Subsequently, the power control 7020 determines whether or not the value of the monitor time value 7203 is less than the minimum monitor time value (step 2053). If less, the power control replaces the monitor time value 7203 with the minimum monitor time value (step 2054) and terminates the processing (step 2070). Accordingly, the monitor time will not become shorter than the minimum time. If the value of the monitor time value 7203 is not less than the minimum monitor time value, the power control terminates the processing (step 2070).
If the power control 7020 determines that the counter value 7202 is less than the reference monitor time in step 2051, the program step will proceed to step 2062 as mentioned above.
The power control 7020 determines that the frequency of access to the disk drive 7004 is increased since the count value 7020, that is, the off time is less than the reference monitor time and increases the monitor time value 7203 by the increased value (step 2052). This extends the monitor time so that the period of time until the supply of power to the disk drive 7004 is turned off is extended.
Subsequently, the power control 7020 determines whether or not the value of the monitor time value 7203 is larger than the maximum monitor time value (step 2063). If larger, the power control replaces the monitor time value 7203 with the maximum monitor time value (step 2064) and terminates the processing (step 2070). Accordingly, the monitor time will not become longer than the maximum time. If the value of the monitor time value 7203 is not more than the maximum monitor time value, the power control terminates the processing (step 2070).
Thereafter, the program step will proceed to step 2005 shown in FIG. 10 and the processing is performed.
Although the reference monitor time, the minimum monitor time, the maximum monitor time, the incremented value of the monitor time, and the decremented value of the monitor time are set to 30 seconds, 5 seconds, 3 minutes, 15 seconds and 15 seconds, respectively, since a floppy disk drive is used as the disk drive 7004 in the present embodiment, these times are not limited to these values.
The power control 7020 may not be implemented by the program stored in the CPU 7001 and may be implemented by an exclusive CPU 7002 as shown in FIG. 12. Also in this case, the processing shown in FIGS. 9 to 11 can be performed without changing the program, etc. since it is completely independent of the other data processing.
The monitor time until the supply of power to the disk drive is dynamically changed depending upon the condition of access to the disk drive 7004 in the foregoing embodiment as mentioned above. Accordingly, the supply of power to the disk drive 7004 is turned off after the lapse of the monitor time which is shorter or longer if the access frequency is lower or higher, respectively. Thus, the power consumed by the disk drive 7004 can be suppressed without the power being frequently re-applied. The power control which has been described above is applicable to ordinary electronic equipment as well as the information processing system.
As mentioned above, in a first aspect of the present invention, supply of clock or power to respective hardware devices can be continued while they are in use and can be stopped while they are not used.
Accordingly, supply of power to the hardware devices which are not involved in the processing which is being executed by users can be stopped at any time even while the users actually use the information processing system. Thus, the power which is consumed by the whole of the information processing system can be suppressed to the minimum without having adverse effects on the processing speed.
In a second aspect of the present invention since an information processing system, a power source monitor and a disk drive apparatus, etc. change the period of time until the power source is turned on or off depending upon the operating condition of the apparatus, the power consumed by the apparatus can be effectively suppressed.
Application of both aspects of the present invention can cause power to be more effectively suppressed.
Many different embodiments of the present invention may be constructed without departing from the spirit and scope of the invention. It should be understood that the present invention is not limited to the specific embodiments described in this specification. To the contrary, the present invention is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the claims. | A power consumption control apparatus for an information processing apparatus having multi-tasking control which executes a plurality of information processing operations in parallel by time-divisionally switching a plurality of tasks in an arithmetic processing unit. The power consumption controlled apparatus detects an event where there are no information processing operations to be executed, sets the arithmetic processing unit to a power-saving mode in response to the event and immediately clears the power-saving mode set in the arithmetic processing unit in response to an interrupt signal from an input/output device. Alternatively, the power consumption control apparatus after detecting the event stops supply of a clock to the arithmetic processing unit or lowers a frequency of the clock in response to the event. Thereafter, the power consumption control apparatus immediately resumes supply of the clock to the arithmetic processing unit or raises the frequency of the clock in response to an interrupt signal from an input/output device. | 8 |
BACKGROUND OF THE INVENTION
This invention relates generally to headwear and, in particular, to baseball caps. It is one purpose of the invention to provide a modified baseball cap that can be used as a glove to catch baseballs. The cap of this invention is intended especially for baseball fans who can use it to catch foul balls or home runs hit into the stands.
U.S. Pat. Nos. 2,615,168, 4,165,542, 4,312,076, and 4,386,437 all relate to hats or sport caps having pockets in the crown for the storage of small articles such as keys, coins, licenses, etc. U.S. Pat. No. 2,688,204 discloses a helmet containing a fish landing net and U.S. Pat. No. 4,484,363 shows a cap having a pocket containing a coolant. None of these suggest use of headwear as a baseball glove or even as glove means.
In preferred form, the invention uses a baseball cap that is available on the open market. A flexible, fabric web is inserted inside the crown of the cap and suitably secured to the cap body. The web is preferably large enough to serve as a liner for the cap and preferably padded to serve as a baseball glove. The user's hand can be inserted through the usual headsize adjustment opening at the rear of the cap so that it is between the padded portion (where the palm of the user's hand will be) and the upper crown. In this hand position, the cap has been converted into a baseball glove and can be employed by the user to catch a baseball.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing the cap of the invention in use as a glove to catch an approaching baseball;
FIG. 2 is a bottom plan view of a baseball cap embodying the invention;
FIG. 3 is an end elevation taken from the back of a cap such as shown in FIGS. 1 and 2;
FIG. 4 is a cross section along the line 4--4 of FIG. 2;
FIG. 5 is a cross section along the line 5--5 of FIG. 2; and
FIG. 6 is a cross section showing the cap used as a cap.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring first to FIG. 1, a headwear 1 in accordance with the invention is shown in use as a glove. The user's hand 2 is inside the headwear (in the form of a baseball cap) and the user's arm 3 is extended to align the glove means 5 in the cap with the approaching baseball 7. Thus, the headwear 1 is converted into a baseball glove and FIG. 1 illustrates how it may be used by a baseball fan to catch a foul ball or home run hit into the stands at a baseball game.
As shown in the various Figures, the headwear 1 of the invention preferably uses an ordinary baseball cap 9 available on the open market. This comprises a cap body 10 that has a crown portion 11 to fit over the head of a user and a stiff visor 13 at the front of the cap body. The crown portion 11 is formed from six pie-shaped segments 14 which meet at the top button 15 and are seamed to each other along radial lines 17 extending downwardly from the top button 15. The bottom, wide parts of the segments 14 are secured to the bottom rim band 19. The band 19 is attached at the front of the cap to the visor 13 and has left and right hand portions 19L and 19R, respectively, extending rearwardly from the visor 13 and defining the bottom of the crown portion 11. The cap 9 is of the adjustable headsize type so that in the back the band portions 19L and 19R terminate a substantial distance away from the midplane of the cap as identified by seam line 17M. However, head size adjustment strap members 21L and 21R are securely attached to band portions 19L and 19R, respectively, and extend circumferentially to substantially overlap each other. Suitable connecting means 23, such as pins on one strap member and pin receiving holes on the other, are provided to secure one strap member to the other in the desired position of overlap, thereby determining the headsize of the cap 1. The band 19 and strap members 21L and 21R act together to define the adjustable head receiving opening 24 at the bottom of the cap, i.e., the maximum cross section of crown 11.
Headsize adjustment is customarily facilitated in baseball caps of the type illustrated by foreshortening the inner portions of the two rear crown segments 14 as shown at 25. The effect of this is to provide an opening 27 of substantial size at the rear of the cap. The strap members 21L and 21R extend across this opening and the extent of their overlap determines the width of the opening and the headsize of the cap. The size of opening 27 above the strap member 21L and 21R is, with caps now on the open market, ordinarily large enough to allow the hands of children and many adults to pass through it. Thus, their hands can generally be inserted into the interior of the crown portion 11 of the cap through opening 27. This is generally true even for different size caps because a person's hands and head tend to be proportional in size. The opening 27 can be made larger in a given cap by connecting strap members 21L and 21R together in the minimum overlap position or by leaving then unconnected. It may be noted that the opening 27 is separate from the head opening 24 when the members 21L and 21R are connected.
In the presently preferred embodiment illustrated in the drawings, the glove means 5 includes a flexible web member 31 that extends across the full cross section of the cap and is secured around most of its periphery to the band 19 of the cap body 10. It is not secured to the band or cap body 19 at the rear of the cap in line with hand opening 27. This allows a hand 2 to be inserted into the space between the web member 31 and the top of the crown 11. The web member periphery is secured to the band 19 by sewing, stitching, mechanical fasteners, adhesion, or other suitable means as indicated at 32.
The bottom of the web member 31 is engaged by the user's head when the cap is used as headwear. The web has enough material and slack in it, as shown at 34, so that it will substantially mold itself around the head H of the user and to the inside of the crown 11 of the cap as shown in FIG. 6. Thus, it performs the function of a liner for the crown 11 as well as the function of a glove means.
The web member 31 is preferably a laminated construction formed in part by two layers 37 and 39 of cloth. The palm portion 41 of web member 31, where a ball is likely to be caught, preferably contains a layer of padding 45 between fabric layers 37 and 39 to help protect the user's hand against the sting of a hard ball. As seen best in FIGS. 1 and 4, the web member 31 also preferably includes a padded heel portion 43 that extends out of cap head opening 24 below opening 27 and straps 21L and 21R. Thus, portion 43 covers and will help protect the user's wrist against impact of a ball 7.
FIG. 6 illustrates use of the headwear 1 as a cap with the web member 31 serving as a liner for the crown 11. FIGS. 1 and 4 illustrate use of the headwear 1 as a glove means wherein the left hand 2 of a user is inserted between the web member 31 and the top of the crown 11. FIG. 4 shows the hand 2 inserted below strap member 21L and 21R. It is to be understood that if the opening 27 is large enough and/or the hand 2 is small enough, the hand 2 could be inserted above the strap members through the opening 27.
Modifications may be made in the specific construction shown without departing from the spirit and scope of the invention. | A baseball cap has a large flexible web extending across the full cross section of the cap and secured to the band with hand access to the space between the crown of the cap and the web being provided by openings at the rear of the cap both above and below the overlapping headsize adjusting straps whereby the web can serve as a glove for a hand inserted through either one of the openings. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
The present application is a continuation of U.S. patent application Ser. No. 13/033,951, filed Feb. 24, 2011, now U.S. Pat. No. 8,179,586, which is a continuation of U.S. patent application Ser. No. 12/580,499, filed Oct. 16, 2009, now U.S. Pat. No. 7,898,719, which is a continuation of U.S. patent application Ser. No. 12/260,499, filed Oct. 29, 2008, abandoned, which is a continuation of U.S. patent application Ser. No. 10/956,749, filed Oct. 1, 2004, now U.S. Pat. No. 7,446,924, which claims the benefit of U.S. provisional application Ser. No. 60/508,086, filed Oct. 2, 2003, which are hereby incorporated herein by reference in their entireties.
FIELD OF THE INVENTION
The present invention relates generally to rearview mirror assemblies for vehicles and, more particularly, to rearview mirror assemblies that include one or more electronic components, such as electro-optic or electrochromic interior rearview mirror assemblies. However, aspects of the present invention may be equally suitable for use in prismatic rearview mirror assemblies and/or for exterior rearview mirror assemblies.
BACKGROUND OF THE INVENTION
It is known to attach a printed circuit board to an attachment plate adhered or otherwise affixed to a rear surface of a mirror element, such as an electro-optic reflective element assembly or a prismatic reflective element. In order to attach the printed circuit board to the attachment plate, various connectors or clips may be employed at the attachment plate and/or the circuit board. The attachment plate is typically adhered to the rear surface of the mirror element or substrate, such as via a suitable adhesive or tape or the like. The printed circuit board has a rigid printed board or substrate that is cut or formed to a desired form and has conductive traces and circuitry applied to or placed on or attached to the board. The attachment plate and printed board/substrate include multiple parts and components at the rear of the mirror element, which may be costly to manufacture and assemble. The multiple components also add to the size, weight and volume requirements for the circuit board, which thus may add to the size and weight of the mirror assembly. Also, the printed board or substrate material may add to the weight and to the cost of the mirror assembly.
Therefore, there is a need in the art for an interior rearview mirror assembly that overcomes the shortcomings of the prior art.
SUMMARY OF THE INVENTION
The present invention provides an interior or exterior rearview mirror reflective element assembly that includes a conductive trace and circuitry printed on and/or applied at or to the rear surface of the mirror reflective element assembly, such as to the rear surface of the rear reflective element substrate of an electro-optic or electrochromic mirror reflective element assembly or cell. The circuitry thus may be applied to the existing hard or rigid reflective element substrate (typically glass) of the mirror reflective element assembly, such that the reflective element assembly comprises a circuitry on glass arrangement (although the reflective element substrate may comprise other materials, such as acrylic or polycarbonate or the like, without affecting the scope of the present invention), and does not require the additional printed board or substrate and attachment plate of conventional mirror assemblies. The glass substrate or reflective element substrate of the mirror reflective element assembly thus provides the hard or rigid surface for the conductive trace and electrical components and replaces the hard or rigid printed board or substrate of conventional printed circuit boards. The circuitry on glass assembly of the present invention may be applied to reflective elements or reflective element assemblies of interior mirror assemblies, such as interior rearview mirror assemblies and the like, or of exterior mirror assemblies, such as exterior rearview mirror assemblies and the like, or of other mirror assemblies of vehicles, without affecting the scope of the present invention.
According to an aspect of the present invention, a reflective element assembly for a mirror assembly of a vehicle includes a reflective element substrate (typically glass) having a rear surface (the surface facing generally away from the driver of the vehicle and facing generally forwardly with respect to the direction of travel of the vehicle when the mirror assembly is installed to the vehicle) and a front surface (the surface facing generally toward a driver of the vehicle and generally rearward with respect to the direction of travel of the vehicle when the mirror assembly is installed to the vehicle). The reflective element assembly includes a conductive trace or layer disposed at the rear surface of the reflective element substrate and a non-conductive layer applied to the conductive trace and covering at least some of the conductive trace and leaving at least one portion of the conductive trace exposed. The reflective element assembly includes at least one circuitry component that is applied to at least one of the portions of the conductive trace.
The reflective element substrate may have a reflective layer disposed at one of the front and rear surfaces for viewing by a driver of the vehicle when the mirror assembly is installed to the vehicle. The conductive trace and at least one circuitry component thus are disposed at the rear surface of the existing rigid reflective element substrate (typically glass) that includes or is associated with the reflective surface of the reflective element assembly that is viewable by the driver of the vehicle.
For example, a third surface electro-optic or electrochromic transflective element assembly may include a metallic reflective coating or layer and one or more non-metallic, semi-conductive layers disposed at or on a third surface or front surface of the rear or second reflective element substrate. The rear reflective element substrate of the electrochromic reflective element assembly is positioned rearward of the front reflective element substrate, with an electrochromic medium disposed between the front and rear reflective element substrates. The third surface transflective element assembly thus may provide a reflective surface for viewing by the driver of the vehicle through the front reflective element substrate of the reflective element assembly. Alternately, a fourth surface electro-optic or electrochromic reflective element assembly may have a reflective coating or layer disposed on a fourth or rear surface of the rear reflective element substrate for viewing by a driver of the vehicle through the front and rear reflective element substrates or glass substrates of the reflective element assembly or cell. Alternately, the rear surface of a prismatic element or substrate may have a reflective layer disposed thereon or applied thereto for viewing by the driver of the vehicle.
In any of these embodiments, the conductive trace of the present invention may be applied at the rear surface of the rear reflective element substrate (or the rear surface of the single substrate for prismatic type mirror assemblies) and rearward of the reflective layer or coating so that the conductive trace and electronic components are not viewable by the driver of the vehicle through the reflective element substrate or substrates of the reflective element assembly. In applications where the reflective layer is disposed at the rear or fourth surface of an electro-optic or electrochromic reflective element assembly or cell, an insulating layer may be applied at the rear surface and over the reflective layer or layers, whereby the conductive trace may be applied to the insulating layer. The present invention thus utilizes the existing reflective element substrate of the mirror reflective element assembly as the rigid substrate for receiving the conductive trace and electronic components and/or circuitry.
According to another aspect of the present invention, a method of manufacturing a reflective element assembly for an interior rearview mirror assembly of a vehicle includes providing a reflective element substrate having a front surface and a rear surface. The reflective element substrate has a reflective layer disposed at one of the front and rear surfaces for viewing by a driver of the vehicle when the mirror assembly is installed to the vehicle. A conductive trace or layer is applied to or disposed at the rear surface of the reflective element substrate. A non-conductive layer is applied to the conductive layer to cover at least some of the conductive layer and to leave at least one portion of the conductive layer exposed. At least one circuitry component is applied to the at least one exposed portion of the conductive layer. The conductive trace or layer may comprise a conductive epoxy, such as a conductive silver epoxy or the like, and may be applied in a desired pattern onto the rear surface of the reflective element substrate.
The method may include providing the non-conductive material or layer or mask over portions of the conductive trace while exposing other portions or pads for receiving at least one accessory and/or circuitry component or the like, such as sensors, resistors, capacitors, display elements, and the like, thereon. Optionally, a display element, such as a light emitting diode (LED) display element, a vacuum fluorescent (VF) display element, an electroluminescent (EL) display element, a liquid crystal display (LCD) element, or a video display element or the like, may be integrally formed at the rear surface of the reflective element substrate, such that the display information is viewable through the reflective element substrate. Optionally, at least one proximity sensor or antenna may be applied to or clipped to or attached to or positioned along a portion of the rear surface of the reflective element substrate. The at least one proximity sensor or antenna may be operable to detect a presence of a person's finger at or near the mirror assembly, such as at or near one of the sensors or at or near a corresponding icon on or at the mirror casing or bezel and at which or behind which the proximity sensor is located. The circuitry or component may be operable to actuate a display menu or the like and/or actuate or toggle or control an accessory in response to such a detection.
The accessories or circuitry or electrical components may be applied or adhered to the exposed portions or pads of the conductive trace before the conductive trace has cured, such that the curing of the conductive trace may secure the accessories and the like to the conductive trace, or the accessories or circuitry or components may be adhered or secured to the exposed portions after curing of the conductive trace, without affecting the scope of the present invention.
The mirror reflective element assembly may comprise an electro-optic or electrochromic mirror reflective element assembly or cell having first and second reflective element substrates. The conductive trace may be applied to the fourth or rear surface of the second or rear reflective element substrate of the electrochromic mirror reflective element assembly. The electrochromic mirror reflective element assembly or cell may include clips or busbars extending at least partially along the upper edge of one of the reflective element substrates and the lower edge of the other of the reflective element substrates. The conductive trace may include portions that extend substantially to the upper and lower edges of the second reflective element substrate to facilitate connection to the clips or busbars. The clips or busbars may contact portions of the conductive trace applied to the rear or fourth surface of the rear or second reflective element substrate to connect the busbars to the circuitry or the like associated with or connected to the conductive trace.
Therefore, the interior rearview mirror assembly of the present invention provides a mirror reflective element assembly, such as an electro-optic or electrochromic mirror reflective element assembly or cell or a prismatic reflective element assembly, that includes a conductive trace and circuitry applied to or disposed at a rear surface of a reflective element substrate, such as a rear glass substrate of an electro-optic or electrochromic reflective element assembly or a single glass substrate of a prismatic reflective element assembly or the like, such that at least one electronic component and/or circuitry is integral with the reflective element substrate of the reflective element assembly. The reflective element assembly thus provides a circuitry on glass arrangement and thus utilizes the existing rigid glass reflective element substrate of the reflective element assembly as the rigid surface that receives the conductive trace and circuitry or electronic components thereon. The electronic components and/or circuitry thus are not provided on a separate rigid printed board or substrate that may be snapped onto or otherwise attached to an attachment plate adhered to or otherwise positioned at the rear surface of the reflective element. The rearview mirror reflective element assembly of the present invention thus provides a compact reflective element assembly, which may be readily manufactured, because the reflective element assembly does not include an attachment plate or the like. The mirror reflective element assembly of the present invention thus may provide a low cost, lightweight and compact reflective element assembly that provides for enhanced manufacturing and assembly processes.
These and other objects, advantages, purposes and features of the present invention will become apparent upon review of the following specification in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an interior rearview mirror assembly in accordance with the present invention;
FIG. 2 is a front elevation of a rear reflective element substrate of a reflective element assembly of the mirror assembly of FIG. 1 , viewing through the reflective element substrate to show a conductive trace applied to the rear surface of the substrate;
FIG. 3 is a rear elevation of the rear reflective element substrate of FIG. 2 ;
FIG. 4 is an enlarged rear elevation of the rear reflective element substrate of FIGS. 2 and 3 , with components and/or circuitry attached to the conductive trace;
FIG. 5 is a rear perspective view of an electrochromic mirror reflective element assembly having the rear reflective element substrate of FIGS. 2-4 ;
FIG. 6 is a sectional view of the electrochromic mirror reflective element assembly of FIG. 5 ; and
FIG. 7 is a rear perspective view of a portion of a reflective element assembly of the present invention, with a light pipe attached between circuitry on the reflective element substrate and a bezel portion of the mirror assembly.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings and the illustrative embodiments depicted therein, an interior rearview mirror assembly 10 includes a casing 12 , a bezel 13 , a reflective element assembly or cell 14 and a mounting arrangement 16 ( FIG. 1 ) for adjustably mounting the casing and reflective element 14 to an interior portion of a vehicle, such as to a mounting button or the like at an interior surface of a windshield of a vehicle. Mirror reflective element assembly 14 includes a conductive trace or layer or coating 18 ( FIG. 2 ) applied to or disposed on or at the rearward surface (the surface facing forward or in the direction of travel of the vehicle when the mirror assembly is installed in the vehicle) of a reflective element substrate, such as the typically glass substrate of the reflective element assembly, such as on the rear surface 20 a ( FIGS. 3-6 ) of a second or rear substrate or glass element 20 of an electro-optic or electrochromic mirror cell (commonly referred to as the fourth surface of the electrochromic mirror cell). The reflective element substrate 20 thus may provide a substantially rigid surface for receiving the conductive trace and circuitry, and the reflective element assembly thus may comprise a circuitry on glass arrangement, whereby no separate rigid printed board or substrate or attachment plate is necessary to support the conductive trace and circuitry at the rear of the reflective element substrate of the reflective element assembly. However, the reflective element assembly and/or the mirror assembly may include other electronic elements or circuitry that may not be positioned or disposed on the glass surface, and/or that may complement the circuitry on the glass substrate, without affecting the scope of the present invention.
In the illustrated embodiment, the reflective element assembly 14 comprises an electro-optic or electrochromic reflective element assembly or cell that includes a front reflective element substrate 22 and the rear reflective element substrate 20 . The rear reflective element substrate 20 is spaced from front reflective element substrate 22 with an electrochromic medium 21 and conductive or semi-conductive layers disposed or sandwiched therebetween, as is known in the electrochromic mirror art. The conductive trace 18 may be applied directly onto the rear surface 20 a (or onto an insulating epoxy or other type of layer or coating applied to the rear surface, as discussed below) of the reflective element substrate 20 , and masking portions or layers of a non-conductive material 24 and circuitry components and/or accessories and the like may be applied directly to the conductive trace 18 , such that no separate printed board and attachment plate and related components are required.
Although shown and described as an electrochromic reflective element assembly or cell, aspects of the present invention may be equally suitable for and applicable to a prismatic reflective element substrate and assembly or other types of reflective elements and assemblies, without affecting the scope of the present invention. Also, although shown and described as an interior reflective element assembly, aspects of the present invention may be equally suitable for and applicable to exterior mirror assemblies, such as exterior electrochromic rearview mirror assemblies and exterior rearview mirror assemblies with a single reflective element and the like, without affecting the scope of the present invention.
The conductive trace or layer 18 may comprise a conductive epoxy, such as a conductive silver epoxy or the like, that may be screen printed in a desired pattern or trace directly onto the rear surface 20 a of rear reflective element substrate 20 of reflective element assembly 14 (or onto an insulating layer or the like at the rear surface of the reflective element substrate). In FIG. 2 , rear reflective element substrate 20 of reflective element assembly 14 is shown from the front side or surface 20 b , so that the conductive trace 18 is shown at the rear surface 20 a of reflective element substrate 20 by viewing through the transparent reflective element substrate 20 .
If the mirror reflective element assembly or electrochromic cell 14 comprises a third surface reflective element assembly (where the front surface of the rear substrate, commonly referred to as the third surface of the reflective element assembly or cell, has a reflective and conductive metallic coating or layer or layers 39 a ( FIG. 6 ), such as a silver or aluminum or chromium or rhodium or other metallic materials or alloys thereof, and one or more non-metallic semi-conductive layers, such as one or more layers of indium tin oxide (ITO), indium tungsten oxide (IWO), indium cerium oxide (ICO), indium oxide (IO) or the like, disposed thereon or applied thereto), the conductive layer or epoxy 18 may be applied directly to a clean glass surface at the rear surface of the rear reflective element substrate (or may be applied to an insulating layer or the like applied directly to the clean glass surface).
Alternately, if the mirror reflective element or electrochromic cell 14 comprises a fourth surface reflective element (where the reflective coating or layer 39 b ( FIG. 6 ), such as a metallic layer or the like, is applied to the rear or fourth surface of the rear reflective element substrate of the cell), the protective paint layer or layers that are typically applied to the rear surface of the rear reflective element substrate may be replaced or covered with an insulating epoxy layer to provide an insulated surface at the rear of the rear reflective element substrate. The conductive trace 18 may then be applied to the insulating epoxy layer at the fourth surface of the reflective element assembly or cell.
The conductive epoxy layer may be applied as a conductive trace in the desired pattern onto the appropriate rear surface of the reflective element substrate. For example, the conductive epoxy may be screen printed onto the rear surface of the reflective element substrate in the desired pattern, such as shown in FIG. 2 . Optionally, the conductive epoxy layer or coating may be applied over a substantial amount of the rear surface of the rear reflective element substrate and may function as an anti-shatter or anti-scatter element to limit or substantially preclude shattering/scattering of the glass reflective element substrate, such as in situations where the vehicle is involved in an accident or the like.
Optionally, the conductive trace and the mask or non-conductive layers and exposed pads or portions may be formed on the rear surface in a similar manner as it is typically formed on a conventional printed circuit board. For Example, a copper layer may be applied to the rear surface of the glass reflective element substrate and the masking or non-conductive layer may be screen printed onto the copper layer and etched away to form the desired pattern, without affecting the scope of the present invention.
After the conductive epoxy or trace has been screen printed or otherwise applied to the rear surface of the reflective element reflective element, the trace may be masked over with a non-conductive or masking layer 24 ( FIGS. 3-5 ) that covers the conductive trace except at portions or pads 18 a ( FIG. 3 ) of conductive trace 18 for affixing circuitry and components thereto, as discussed below. The non-conductive layer 24 may substantially cover the conductive trace except in areas where components or wires or accessories or the like may be positioned to provide the desired function to the reflective element assembly or cell 14 . The components or wires or accessories (shown generally at 26 in FIGS. 4 and 6 ) may be affixed to the appropriate portions or pads 18 a that are exposed through the masking layer 24 to complete the circuitry that is integral with the mirror reflective element assembly or cell.
Also, after the conductive trace or epoxy layer has been screen printed or otherwise applied to the rear surface of the reflective element substrate, the conductive layer may be cured. It is envisioned that the conductive layer may be cured onto the rear surface of the reflective element substrate at the same time that the electrochromic reflective element assembly or cell is cured (such as at the same time that the epoxy seal 21 a ( FIG. 6 ) that is disposed around the electrochromic medium and between the substrates is cured) to cure both the conductive epoxy layer and the epoxy seal of the electrochromic cell with the same curing process. The epoxy seal and the epoxy trace or layer may be cured via an air curing process or an oven curing process or the like, without affecting the scope of the present invention.
Optionally, the non-conductive layer and electronic components or circuitry may be applied to the conductive layer and pads or portions of the conductive layer before the conductive layer has been cured. The components may thus be temporarily affixed to the conductive pads, such as via adhesive dots or drops or the like applied (and optionally robotically applied) to the pads and/or the components, and then the reflective element assembly and epoxy seal and/or circuitry may be cured to secure the circuitry and components to the conductive trace applied to the rear surface of the mirror reflective element assembly. Such an approach provides for attachment of the components and curing of the conductive layer, and optionally of the epoxy seal of the reflective element assembly as well, in a single step, thereby substantially enhancing the manufacturing processes for manufacturing the electrochromic mirror reflective element assembly or cell.
The circuitry and components, such as resistors, capacitors, jumpers, and clips and the like, and accessories, such as sensors, display elements, such as light emitting diodes (LEDs), liquid crystal display elements (LCDs), vacuum fluorescent (VF) display elements, electroluminescent (EL) display elements or video display elements or other types of display elements or displays, sensors or antennae and the like, may be applied to and secured to the appropriate exposed pads or portions of the conductive trace, such as after the trace has been masked or covered by the non-conductive layer or material. Some of the electronic components or circuitry may also be screened or applied to the conductive trace. For example, it is envisioned that carbon ink resistors may be printed onto the conductive trace with another printing pass or screening pass. The carbon ink resistors may be applied utilizing lasers to tighten the tolerances to a desired level. This approach may reduce the need for separate resistors that would otherwise have to be applied during a later step. However, other known or conventional type resistors may be attached to the appropriate pads or portions, without affecting the scope of the present invention. In situations where circuitry paths need to cross over one another (in such situations, the other side of a printed circuit board is used to make such a cross over in a conventional printed circuit board), a zero ohm jumper or resistor may be attached to spaced apart pads or portions of the conductive trace to bridge or span the gap between the pads or portions and effectively cross over a portion of a conductive trace positioned between the spaced apart pads or portions.
Although described above as being applied directly to the rear surface of the reflective element substrate and being cured thereon, it is envisioned that the conductive trace may be applied to a substantially non-stick surface and cured thereon and then peeled from the surface and applied to the rear surface of the reflective element substrate as a pre-cured flexible conductive trace. This may be preferred in some applications to minimize the waste of conductive traces in situations where some of the reflective element assemblies may be discarded or scrapped due to defects in the reflective element assemblies. The conductive trace may then be applied to a reflective element substrate of a reflective element assembly or cell after the epoxy seal has been cured and after the reflective element assembly or cell has met the quality requirements. The conductive trace may be a flexible element that may be readily applied to or adhered to the reflective element substrate surface.
It is further envisioned that the conductive trace may be initially applied to the separate surface, and the non-conductive layer or masking and the circuitry and electronic components and accessories may be applied to the conductive trace, such as in the manner as described above. The pre-cured flexible circuit sheet may then be peeled from the surface and applied to or rolled onto the rear surface of the reflective element substrate. The busbars and other accessories or components may be connected to the appropriate exposed pads or portions of the conductive trace on the flexible circuit sheet either while the flexible circuit sheet is at the separate surface or at another surface, or after the sheet has been applied to the rear surface of the reflective element substrate. The flexible circuit sheet may be adhered to or bonded to or otherwise secured to the rear surface of the reflective element substrate via any suitable means, without affecting the scope of the present invention.
As discussed above, the rearview mirror reflective element assembly of the present invention may comprise an electro-optic or electrochromic reflective element assembly or cell, such as an electrochromic mirror reflective element assembly utilizing principles disclosed in commonly assigned U.S. Pat. Nos. 6,690,268; 5,140,455; 5,151,816; 6,178,034; 6,154,306; 6,002,544; 5,567,360; 5,525,264; 5,610,756; 5,406,414; 5,253,109; 5,076,673; 5,073,012; 5,117,346; 5,724,187; 5,668,663; 5,910,854; 5,142,407; and/or 4,712,879, which are hereby incorporated herein by reference, and/or as disclosed in the following publications: N. R. Lynam, “Electrochromic Automotive Day/Night Mirrors”, SAE Technical Paper Series 870636 (1987); N. R. Lynam, “Smart Windows for Automobiles”, SAE Technical Paper Series 900419 (1990); N. R. Lynam and A. Agrawal, “Automotive Applications of Chromogenic Materials”, Large Area Chromogenics: Materials and Devices for Transmittance Control, C. M. Lampert and C. G. Granquist, EDS., Optical Engineering Press, Wash. (1990), which are hereby incorporated by reference herein.
As shown in FIGS. 4 and 5 , mirror reflective element assembly or cell 14 may include front reflective element substrate 22 and rear reflective element substrate 20 with electrochromic medium 21 sandwiched therebetween. The front reflective element substrate 22 has a front surface 22 a (the first surface of the electrochromic cell) and a rear surface 22 b (the second surface of the electrochromic cell), which may include one or more transparent semi-conductive layers (such as an ITO layer or the like, or such as disclosed in PCT Application No. PCT/US03/29776, filed Sep. 19, 2003 and published Apr. 1, 2004 as International Publication No. WO 2004/026633, which is hereby incorporated herein by reference) thereon. The rear reflective element substrate 20 may include one or more transparent semi-conductive layers (such as an ITO layer or the like), and/or a metallic conductive layer (such as a layer of silver, aluminum, chromium or the like or an alloy thereof), on its front surface 20 b (the third surface of the electrochromic cell), and may include multiple layers such as disclosed in PCT Application No. PCT/US03/29776, filed Sep. 19, 2003 and published Apr. 1, 2004 as International Publication No. WO 2004/026633, which is hereby incorporated herein by reference. The reflective element assembly 14 thus may comprise a third surface transflective element assembly or cell, whereby the reflective layer or surface is disposed at the third surface of the cell or at the front surface of the rear reflective element substrate for viewing by a driver of the vehicle.
Electrochromic reflective element assembly or cell 14 may include a front busbar or clip 30 that may engage or clip onto an edge portion (such as an upper edge portion 22 c ) of front reflective element substrate 22 to provide electrical power or current to the semiconductive layer or layers on the rear surface 22 b of front reflective element substrate 22 . The cell 14 may also include a rear busbar or clip 32 that may engage or clip onto an edge portion (such as a lower edge portion 20 c ) of rear substrate 20 to provide electrical power or current to the semiconductive or conductive layer or layers on the front surface 20 b of rear substrate 20 . The front clip 30 may include an extension 30 a that extends rearward over the rear substrate 20 and that engages a busbar pad 18 b at an upper portion of the conductive trace 18 , while the rear clip 32 may engage a busbar pad 18 c at a lower portion of the conductive trace 18 , such that electrical power or current may be applied to front clip 30 and to rear clip 32 to darken or color the electrochromic medium 21 as desired.
The extension 30 a of front clip or busbar 30 may be a separate extension attached to the clip or busbar, or may be integral with the clip or busbar, without affecting the scope of the present invention. The conductive trace 18 and exposed portions or pads 18 b , 18 c may extend to the upper and lower edges of the reflective element substrate and may act as a conductive rail along the edges so the clips 30 , 32 may contact the conductive trace directly, with no wiring being necessary to connect the clips or busbars to the circuitry. The present invention thus may avoid the need to solder leads onto the busbars as is typically required with conventional busbars, such that the electrochromic mirror reflective element assembly of the present invention may provide for enhanced manufacturing processing. Optionally, an ASIC (application specific integrated circuit) die with external capacitors and clips may be applied at or near the upper and lower edges of the rear reflective element substrate for connection to the electrochromic clips or busbars 30 , 32 . Optionally, and as shown in FIG. 4 , the extension 30 a may comprise a wire or lead that is soldered or otherwise conductively connected or secured to the busbar pad 18 b to connect an end or portion of the clip or busbar 30 to the busbar pad 18 b , without affecting the scope of the present invention. The clips or busbars and substrates and coatings may be configured and may function similar to known busbars and substrates and coatings, or may be of the types described in PCT Application No. PCT/US03/35381, filed Nov. 5, 2003 and published on May 21, 2004 as International Publication No. WO 2004/042457, which is hereby incorporated herein by reference.
The conductive trace 18 and electronic components and/or circuitry 26 may comprise or mount or attach one or more accessories, such as lights, a microphone, user actuatable controls or inputs, sensors, such as photo sensors or the like, or any other type of accessory suitable for such an application, as discussed below. For example, and as shown in FIGS. 4-6 , one or more light sensors or photo diodes 34 , 36 may be attached or mounted to appropriate exposed pads or portions 18 d ( FIG. 3 ) of conductive trace 18 , and may be operable to sense light at the mirror assembly. More particularly, light sensor 34 may be a forwardly facing (with respect to the direction of travel of the vehicle) sensor operable to detect the ambient light at the mirror assembly (such as via detecting light through an opening in the mirror casing or the like that receives light from forward of the mirror assembly and in the direction of travel of the vehicle), while light sensor 36 may be operable to detect glare at the mirror reflective element (such as by detecting light from rearward of the mirror assembly and from rearward of the vehicle). In order for light sensor 36 to detect the glare light rearward of the mirror assembly, it is envisioned that a window or transparent portion or area may be formed in the reflective layer or coating of the reflective element substrates to allow the sensor to view or receive light from rearwardly of the mirror assembly. Alternately, the light sensor may receive light that passes through the electro-optic reflective element assembly or cell, such as in display on demand or transflective cells and the like, without affecting the scope of the present invention.
Optionally, and with reference to FIG. 7 , a light pipe 37 may be implemented to direct light though the bezel or casing of the mirror assembly and to bend the light, such as approximately 90 degrees or approximately 180 degrees (depending on the mounting orientation of the sensor) to direct or deliver the light to the sensor 36 at the circuitry on the back of the rear or second reflective element substrate, without affecting the scope of the present invention. In the illustrated embodiment of FIG. 7 , the light pipe 37 functions to bend the light about 180 degrees to direct light from rearward of the mirror assembly (such as light at the bezel portion 13 ′ of the mirror assembly 10 ′) to the forward facing light sensor or photo sensor 36 at the conductive trace and circuitry 26 at the rear or fourth surface of the reflective element assembly. Optionally, the light pipe may extend between the circuitry and the back of an electrochromic reflective element assembly or cell where the light will be sensed/gathered/received from light passing through the cell, without affecting the scope of the present invention. Such an application may be suitable for use in applications with a transflective or display on demand type of cell. The sensors thus may face in generally the same direction on the circuitry, but may utilize light gathering means, such as one or more light pipes or the like, to gather and/or receive light from different directions, and may utilize aspects of the sensors described in U.S. patent application Ser. No. 10/229,573, filed Aug. 28, 2002, published Mar. 6, 2003 as U.S. Publication No. 2003-0043589, now U.S. Pat. No. 7,008,090, which is hereby incorporated herein by reference.
Although shown and described as comprising an electrochromic reflective element assembly, the present invention is equally applicable to prismatic reflective element assemblies and the like. For example, a conductive trace may be applied to a rear surface of a prismatic or wedge-shaped reflective element substrate, and electronic components and/or circuitry may be applied to the conductive trace, such as in a similar manner as described above, without affecting the scope of the present invention. The prismatic mirror assembly may comprise any type of prismatic mirror assembly, such as prismatic mirror assembly utilizing aspects described in U.S. Pat. Nos. 6,318,870; 5,327,288; 4,948,242; 4,826,289; 4,436,371; and 4,435,042; and PCT Application No. PCT/US04/015424, filed May 18, 2004 and published on Dec. 2, 2004, as International Publication No. WO 2004/103772; and U.S. patent application Ser. No. 10/933,842, filed Sep. 3, 2004, now U.S. Pat. No. 7,249,860, which are hereby incorporated herein by reference. Optionally, the prismatic reflective element may comprise a conventional prismatic reflective element or prism or may comprise a prismatic reflective element of the types described in PCT Application No. PCT/US03/29776, filed Sep. 19, 2003 and published Apr. 1, 2004 as International Publication No. WO 2004/026633; U.S. patent application Ser. No. 10/709,434, filed May 5, 2004, now U.S. Pat. No. 7,420,756; and U.S. provisional application Ser. No. 60/525,952, filed Nov. 26, 2003 by Lynam for MIRROR REFLECTIVE ELEMENT FOR A VEHICLE, which are all hereby incorporated herein by reference, without affecting the scope of the present invention. A variety of mirror accessories and constructions are known in the art, such as those disclosed in U.S. Pat. Nos. 5,555,136; 5,582,383; 5,680,263; 6,227,675; 6,229,319; and 6,315,421 (the entire disclosures of which are hereby incorporated by reference herein), that can utilize aspects of the present invention.
Optionally, the mirror reflective element assembly or cell 14 and electronic components and/or circuitry applied to the rear surface of the rear reflective element substrate may include display elements, such as for a display on demand type of display, such as of the types disclosed in commonly assigned U.S. Pat. Nos. 6,690,268; 5,668,663 and 5,724,187, and/or in U.S. patent application Ser. No. 10/054,633, filed Jan. 22, 2002, now U.S. Pat. No. 7,195,381, and/or in PCT Application No. PCT/US03/29776, filed Sep. 9, 2003 and published Apr. 1, 2004 as International Publication No. WO 2004/026633; and/or PCT Application No. PCT/US03/40611, filed Dec. 19, 2003 and published on Jul. 15, 2004 as International Publication No. WO 2004/058540, which are all hereby incorporated herein by reference.
With such a display, it is not only desirable to adjust the display brightness according to ambient lighting conditions, but it is also desirable to adjust the display brightness such that a sufficient contrast ratio is maintained against the variable background brightness of the reflected scene. Also, it may be desirable to compensate for changes in transmission of the electrochromic device to control rearward glare sources, so that the display brightness appears to be maintained at a generally constant level. The display and/or transmissivity of the electro-optic device may be adjusted to provide the desired function or viewability, such as by utilizing aspects of the systems described in U.S. patent application Ser. No. 10/427,026, filed Apr. 30, 2003, now U.S. Pat. No. 6,918,674, which is hereby incorporated herein by reference. Optionally, the circuitry 26 may include a light emitting diode (LED) array module or the like bonded or placed on or at or connected to the appropriate portions or pads of the conductive trace applied to the rear surface of the rear reflective element substrate and operable to emit light or display information through the mirror cell for viewing through the reflective element substrate or substrates by the driver or occupant of the vehicle. Other types of display elements may be implemented without affecting the scope of the present invention.
Optionally, and as shown in FIG. 6 , the electrochromic mirror cell 14 may incorporate an integrated display element, such as a liquid crystal display (LCD) element 38 , on or at the rear surface 20 a of rear reflective element substrate 20 . Typically, a liquid crystal display element may include two sheets of spaced apart glass sheets with an appropriate conductive pattern printed on one of the surfaces of one of the sheets. The present invention may incorporate such a display on the rear surface of the rear reflective element substrate by applying a clear conductive pattern 38 a (such as an ITO or the like) on the rear surface of the rear reflective element substrate, and such as at a window formed in the silvering or reflective layer of the mirror reflective element assembly or cell. The conductive pattern may be connected directly to the conductive trace applied to the rear surface of the reflective element substrate. An outer LCD glass sheet 40 may be provided with a continuous conductive coating (such as an ITO or the like) on its rear surface 40 a and may be placed at the conductive pattern 38 a and spaced therefrom, such as via glass spacer beads or the like. The glass sheet 40 may include a jumper lead to connect to an appropriate trace or pad at the rear surface 20 a of rear substrate 20 , or a connecting bump or pad may be formed in the trace to span the gap between the glass sheet 40 and the rear surface of the rear reflective element substrate and to connect the conductive trace to the continuous conductive coating on the glass sheet 40 , without affecting the scope of the present invention. The mirror reflective element assembly or cell of the present invention thus may integrate an LCD display onto the reflective element or glass substrate of the reflective element assembly by using the reflective element or glass substrate of the mirror cell as the front glass sheet of the LCD display element.
Optionally, the printed circuit board of the mirror assembly of the present invention may include a display element along or partially along an edge of the board and may include one or more user-actuatable controls or buttons near or adjacent to the display element. The display element may be any type of display element, such as a vacuum fluorescent (YF) display element, a light emitting diode (LED) display element, an electroluminescent (EL) display element, a liquid crystal display (LCD) element, a video screen display element or the like, and may be operable to display various information (as discrete characters, icons or the like, or in a multi-pixel manner) to the driver of the vehicle, such as passenger side inflatable restraint (PSIR) information, tire pressure status, and/or the like. The buttons may be for actuating or controlling various accessories or controls or components associated with the vehicle, such as for a compass calibration setting or zone setting, a telematics actuation, a garage door opener, an electronic toll control (such as disclosed in U.S. Pat. No. 6,690,268, which is hereby incorporated herein by reference), and/or the like, or may be for switching the display between various functions or modes, without affecting the scope of the present invention.
Optionally, and as can be seen with reference to FIG. 1 , electrochromic mirror reflective element assembly or cell 14 may include or may be associated with one or more switchable accessories, which may be toggled via actuation of one or more switches or buttons or inputs 42 at the front of the mirror assembly 10 , such as along the bezel 13 of the mirror assembly 10 . The user inputs or buttons may be for actuating or controlling various accessories or controls or components associated with the vehicle, such as for a compass calibration setting or zone setting, a telematics actuation, a garage door opener, an electronic toll control (such as disclosed in U.S. Pat. No. 6,690,268, which is hereby incorporated herein by reference), and/or the like, or may be for switching the display between various functions or modes, without affecting the scope of the present invention. Optionally, the user inputs may comprise touch sensors or proximity sensing inputs or the like, such as sensors of the types described in U.S. Pat. Nos. 6,001,486; 6,310,611; 6,320,282; 6,627,918; and 5,594,222; and/or U.S. Pat. Publication No. 2002/0044065, published Apr. 18, 2002, now U.S. Pat. No. 7,224,324; and/or U.S. patent application Ser. No. 10/933,842, filed Sep. 3, 2004, now U.S. Pat. No. 7,249,860; and/or PCT Application No. PCT/US03/40611, filed Dec. 19, 2003 and published on Jul. 15, 2004 as International Publication No. WO 2004/058540, which are hereby incorporated herein by reference, or may comprise inputs molded within the bezel of the mirror assembly, such as described in U.S. provisional applications Ser. No. 60/535,559, filed Jan. 9, 2004 by Lindahl for MIRROR ASSEMBLY; and/or Ser. No. 60/553,517, filed Mar. 16, 2004 by Lindahl et al. for MIRROR ASSEMBLY, which are hereby incorporated herein by reference, or may comprise membrane type switches, such as described in U.S. provisional application Ser. No. 60/575,904, filed Jun. 1, 2004 by Uken for MIRROR ASSEMBLY FOR VEHICLE, which is hereby incorporated herein by reference; and/or the like, without affecting the scope of the present invention.
It is envisioned that the inputs 42 may be formed in the bezel 13 and that the circuitry applied to or disposed at the rear surface of the rear reflective element substrate may include one or more proximity sensors or sensing elements or antennae 44 ( FIGS. 5 and 6 ) positioned along a lower edge of the rear surface of the rear reflective element substrate and generally corresponding with a respective one of the inputs 42 . For example, the antenna or antennae or sensing elements may be adhered or clipped or otherwise secured to appropriate exposed pads or portions of the conductive trace 18 to position the antenna or antennae at the desired or appropriate location at the rear of the reflective element substrate. The antenna or antennae or sensing elements 44 may detect the presence of a person's finger at or near the respective input or inputs 42 and may actuate or control a display element or the like or may actuate or control or trigger the circuitry to switch or toggle the device associated with the input 42 in response to such a detection.
As shown in FIG. 5 , the sensing elements 44 may be disposed along the lower or bottom edge of the rear reflective element substrate and may monitor a respective zone around the lower edge of the reflective element substrate or glass substrate. The sensing element or elements may provide a three dimensional cylinder of detection that extends along the bottom edge of the reflective element substrate and that encompasses the respective icon or input 42 at the bezel. As also shown in FIG. 5 , the sensing element may comprise multiple separate sensing elements or antennae or antenna segments that may monitor separate zones corresponding to the respective inputs 42 at the bezel. The inputs 42 at the bezel thus may comprise a screen printed icon or character or the like at the bezel, and may not comprise any movable buttons or inputs or the like. As the user's finger approaches the desired input 42 (or spot or icon on the bezel), the corresponding antenna segment may detect the presence of the finger prior to contact as the finger enters the zone or cylinder of detection for that antenna segment. The electronic components and/or circuitry associated with that particular antenna may then toggle the device or accessory associated with the input, such as between an on/off status, a temperature or compass selection (such as for a temperature/compass display), a degrees F./degrees C. selection (such as for a temperature display), and/or the like.
Optionally, the controls may be operable to activate/deactivate/toggle/control an accessory in response to a detection of a user's finger or the like approaching the input or button region or sensing element at the mirror assembly. Because such inputs may be individual or separate proximity sensors or antennae positioned within the mirror assembly and not readily viewable or discernable by the driver or occupant of the vehicle, the mirror assembly may include a display or indicator that indicates the function of each input. Preferably, the mirror assembly may include a control or circuitry that selectively or occasionally activates a display to temporarily display the feature or function or accessory associated with the particular input or input region of the mirror assembly, such as in response to the user's finger or the like approaching the input area or the like. For example, it is further envisioned that when a user's finger is first detected as it approaches the input region (such as when the user's finger or the like is within a first threshold distance from one of the sensors, such as within about ¼ or ½ of an inch or thereabouts), the control or circuitry may activate a display (such as a display on demand type of display or transflective display that is viewable through the reflective element of the mirror assembly, such as described in U.S. Pat. Nos. 6,690,268; 5,668,663 and/or 5,724,187, and/or in U.S. patent application Ser. No. 10/054,633, filed Jan. 22, 2002, now U.S. Pat. No. 7,195,381, and/or Ser. No. 10/933,842, filed Sep. 3, 2004, now U.S. Pat. No. 7,249,860; and/or PCT Application No. PCT/US03/29776, filed Sep. 9, 2003 and published Apr. 1, 2004 as International Publication No. WO 2004/026633; and/or PCT Application No. PCT/US03/40611, filed Dec. 19, 2003 and published on Jul. 15, 2004 as International Publication No. WO 2004/058540, which are all hereby incorporated herein by reference) that indicates the accessory or feature or function associated with at least some or all of the inputs along the bezel or other region of the mirror assembly. The display may list or indicate the features (such as via text or icons or other indicia) at areas of the reflective element that are near to or generally adjacent to the respective inputs or input regions.
When the user then moves his or her finger to touch or contact the desired or appropriate input (or may move the finger closer to the input region or sensor, such as within a second threshold distance from the sensor that is smaller than the first threshold distance), such as at the bezel or the like, the detection of the contact (or of a closer proximity of the finger) may cause the control to activate/deactivate or toggle/adjust or control the accessory or feature or function associated with that input or input region. As the user's finger is moved closer to or contacts the selected input region, the displays for the other inputs may deactivate so that only the display for the selected input remains viewable by the user. Optionally, the detection of the closer proximity (such as within the second threshold distance or touching) may cause other menus or the like to appear at the mirror assembly, whereby the user may toggle or scroll through the menus to accomplish the desired task or activate/deactivate/adjust the desired or appropriate accessory or function or feature. The user thus may activate/deactivate/toggle/adjust/control the accessory or function or feature associated with the selected input or may scroll through a menu shown in the display at the reflective element.
Optionally, it is envisioned that the control or circuitry may initially activate a display element or display device associated with one of the inputs or buttons or sensor regions, such that as the user's finger approaches a particular input or button or sensor region (such as when the user's finger is within a threshold distance of the input, such as within approximately ¼ or ½ inches or thereabouts of the input or input region), the control or circuitry may activate the respective display that indicates the accessory or feature or function associated with that particular input or input region or sensor. The user thus may move their finger along the front of the mirror assembly (and over and along the separate/distinct sensors or input regions) and view the display or information for the accessory or feature or function associated with each region or input. When the user's finger is located at the desired function, the user may then contact the input region (or may move the finger closer to the input region or sensor), whereby the detection of the contact (or of a closer proximity of the finger) may cause the control to activate/deactivate or toggle/adjust or control the accessory or feature or function associated with that input or input region, or may cause other menus or the like to appear at the minor assembly, such as described above.
The present invention thus provides for the circuitry and electronic components to be kept substantially or entirely at the rear of the mirror reflective element assembly or cell, yet provides for front switching of an accessory or the like. The present invention provides for such front switching in response to a touch or approach of a designated area at the bezel (or elsewhere around the mirror assembly), without any buttons and associated wires or leads being needed at the bezel area. Also, because the proximity sensors or antennae or antenna segments are positioned at the rear of the reflective element or cell, no soldering or otherwise connecting of leads or wires to the buttons at the front of the mirror assembly is required. The present invention thus provides for such functions with a bezel that provides a reduced cost and complexity of the bezel and the casing of the mirror assembly.
The electronic components or circuitry and/or accessories may receive power from the vehicle power source, whereby the vehicle may include wiring to the mirror assembly, such as two wires for power and ground to the mirror assembly. Optionally, the vehicle may incorporate a telematics system, such as an ONSTAR® system or the like, which may have circuitry in the instrument panel of the vehicle. The telematics circuitry may include wires connected to the buttons or inputs at the mirror assembly that provide a toggling function to the telematics system in response to actuation of the respective telematics inputs. It is envisioned that the same wiring to the mirror assembly may also be selectably usable to provide for signal transmission from the telematics system to the mirror assembly, such as for a global positioning system (GPS) function or the like.
Optionally, the power and ground connection may only be provided to the mounting bracket, which may provide an electrical contact to the mirror circuitry via an electrical contact or wiper action at the ball and socket connection of the mounting arm or mounting arrangement of the mirror assembly. For example, the signals may be provided via a mounting arrangement utilizing aspects of the mounting arrangements described in U.S. patent application Ser. No. 10/032,401, filed Dec. 20, 2001, now U.S. Pat. Publication No. US2002/0088916A1, published Jul. 11, 2002, now U.S. Pat. No. 6,877,709; and/or PCT Application No. PCT/US2004/015424, filed May 18, 2004 and published on Dec. 2, 2004, as International Publication No. WO 2004/103772, and/or U.S. provisional application Ser. No. 60/609,642, filed Sep. 14, 2004 by Kamer for MOUNTING ASSEMBLY FOR MIRROR AND METHOD OF MAKING SAME, which are hereby incorporated herein by reference, or may utilize electrical connection principles of the type described in International Publication No. WO 2003/095269 A3, published Nov. 20, 2003 for REARVIEW MIRROR ASSEMBLIES, which is hereby incorporated herein by reference. The signals to control the accessories or circuitry of the mirror assembly may optionally be provided through an infrared link between the mounting bracket and the circuitry in the mirror, such as described in U.S. patent application Ser. No. 10/456,599, filed Jun. 6, 2003, now U.S. Pat. No. 7,004,593, which is hereby incorporated herein by reference.
Optionally, the conductive trace and electronic components or circuitry at the reflective element substrate of the mirror assembly may provide or include or be associated with other accessories, such as a rain sensor (such as the type disclosed in commonly assigned U.S. Pat. Nos. 6,320,176; 6,353,392 and 6,313,454, which are hereby incorporated herein by reference), an image sensor (such as a video camera, such as a CMOS imaging array sensor, a CCD sensor or the like, such as the types disclosed in commonly assigned, U.S. Pat. Nos. 5,550,677; 6,097,023 and 5,796,094, which are hereby incorporated herein by reference), a temperature sensor (such as a contact temperature sensor for measuring the temperature at or of the windshield), an antenna, a compass (such as the types disclosed in U.S. patent application Ser. No. 10/456,599, filed Jun. 6, 2003, now U.S. Pat. No. 7,004,593, which is hereby incorporated herein by reference) or any other sensor or accessory or device. For example, the mirror assembly may include a forward facing video image sensor or system, which may include an intelligent rain sensor (such as the type disclosed in commonly assigned U.S. Pat. Nos. 6,320,176; 6,353,392 and 6,313,454, which are hereby incorporated herein by reference), an image or vision system (including an imaging sensor, such as a video camera, such as a CMOS imaging array sensor, a CCD sensor or the like, such as the types disclosed in commonly assigned, U.S. Pat. Nos. 5,550,677; 6,097,023 and 5,796,094, and U.S. patent application Ser. No. 10/422,378, filed Apr. 24, 2003, now U.S. Pat. No. 6,946,978, which are hereby incorporated herein by reference), an intelligent headlamp controller (such as the type disclosed in U.S. Pat. No. 5,796,094 and/or in U.S. patent application Ser. No. 10/355,454, filed Jan. 31, 2003, now U.S. Pat. No. 6,824,281, which are hereby incorporated herein by reference), an intelligent lane departure warning system, such as the type disclosed in U.S. patent application Ser. No. 10/427,051, filed Apr. 30, 2003, now U.S. Pat. No. 7,038,577, which is hereby incorporated herein by reference, and/or the like. Optionally, the mirror assembly of the present invention may include one or more displays, such as a text display, an iconistic display, a display on demand type display (such as may be implemented with a transflective reflective element, such as described in U.S. Pat. Nos. 6,690,268; 5,668,663 and 5,724,187, which are hereby incorporated by reference herein), a video or touch screen interface display, or the like, and/or one or more sensors or other accessories, such as a biometric imager, such as for fingerprint authentication or the like, an infrared sensor, such as a zonal temperature sensor, such as suitable for an auto climate control, a forward facing image sensor, such as described above, a rearward facing image sensor (such as for biometric imaging (such as for face recognition, iris recognition or the like), seat height or position detection, drowsiness detection, safety/restraints, object detection and position, emergency response image capture system, intrusion detection or the like), and/or an electronic field sensor (such as the type disclosed in commonly assigned U.S. Pat. No. 6,768,420, which is hereby incorporated herein by reference) and/or the like. The display and/or accessories may be associated with a communication system, a speaker, a telematics module (which may include a GPS module, a wireless communication module, an human/machine interface (HMI), a display, such as an LED display, a dot matrix display, an alpha numeric display, a video display or the like, and/or a microphone, which may be operable for speech or voice recognition, noise reduction or noise cancellation), a humidity sensor, a remote keyless entry sensor, a tire pressure monitoring system (TPMS) (such as the types described in U.S. Pat. Nos. 6,731,205; 6,294,989; 6,124,647; 6,445,287; and/or 6,472,979, and/or U.S. provisional application Ser. No. 60/611,796, filed Sep. 21, 2004 by O'Brien for TIRE PRESSURE ALERT SYSTEM, which are hereby incorporated herein by reference), an electronic toll collection sensor, an intelligent headlamp control, user interface controls (such as buttons, switches or the like for controlling various accessories of the vehicle, such as a sunroof, a communication system, lamps, security systems, displays or the like) or any other accessories, sensors, lights, indicators, displays or the like which may be suitable for mounting or positioning at or within the rearview mirror assembly.
The accessories or components of the rearview mirror assembly may be connected to the vehicle electronic or communication systems and may be connected via various protocols or nodes, such as Bluetooth, SCP, UBP, J1850, CAN J2284, Fire Wire 1394, MOST, LIN and/or the like, depending on the particular application of the rearview mirror assembly of the present invention. The rearview mirror assembly may be electronically integrated with the vehicle electrical and/or control systems. For example, the rearview mirror assembly may connect to a sunroof control, rain sensor control, mass motion sensor, roof lighting control, microphone/cell phone control, climate control, and/or the like.
Therefore, the rearview mirror assembly and mirror reflective element assembly of the present invention provides a mirror reflective element assembly that includes the conductive trace and electronic components or circuitry applied directly to or integrated with the rear surface of the reflective element substrate of the mirror reflective element assembly or cell. The present invention thus provides a circuitry on glass arrangement and thus obviates the need for a separate rigid board or substrate for receiving circuitry thereon, and also obviates the need for an attachment plate and associated connectors for attaching such a printed circuit board to the rear of the reflective element assembly or cell. The present invention thus provides a compact and lightweight mirror reflective element assembly that provides enhanced assembly processing and minimizes electrical wiring and connections that may have to be made to connect the circuitry to various components or accessories associated with the mirror reflective element assembly.
Changes and modifications in the specifically described embodiments may be carried out without departing from the principles of the present invention, which is intended to be limited only by the scope of the appended claims as interpreted according to the principles of patent law. | An electrochromic interior reflective element for an interior rearview mirror assembly of a vehicle includes front and rear substrates and an electrochromic medium sandwiched between the front and rear substrates. The electrochromic medium is disposed in an interpane cavity established between a third surface of the rear substrate and a second surface of said the substrate, and the electrochromic medium is bounded by a perimeter seal. A conductive layer is disposed at a fourth surface of the rear substrate. A non-conductive layer covers a covered portion of the conductive layer and leaves an exposed portion of the conductive layer exposed. An electronic circuitry component is disposed at the fourth surface of the rear substrate. The electronic circuitry component is electrically connected to the exposed portion of the conductive layer. | 7 |
The present application claims priority to provisional application Ser. No. 60/018,319, filed May 24, 1996.
This invention was partially made with funds provided by the Department of Health and Human Services under Grant No. NIH-GM49594. Accordingly, the United States Government has certain rights in this invention.
BACKGROUND OF THE INVENTION
The present invention concerns novel approaches for preparation by synthesis of the 3-phosphate derivatives of 1D-1-(1′,2′-di-O-fattyacyl-sn-glycero-3′-phospho)-myo-inositols (PtdIns), referred to as the D-3-phosphorylated phosphoinositides or the 3-PPI (FIG. 1 ), their structural and stereochemical analogues, and key starting materials and intermediates of these approaches.
3-PPI are relatively new members of the phosphoinositide group of cellular lipids with emerging critical roles in intracellular signalling. Synthetic 3-PPI and analogues are needed as reagents for defining their biological functions, and for developing diagnostics and therapeutics.
The 3-PPI (FIG. 1) including phosphatidylinositol-3-phosphate, PtdIns(3)P, and the bius- and tris-phosphate derivatives PtdIns(,43)P 2 and PtdIns(3,4,5)P 3 , have been found in eukaryotic cells (1), and the occurrence of PtdIns (3,5)P 2 has been suggested (2). These compounds have been demonstrated as activators of protein kinase C isoforms δ, ε, and n (3), and are putative messengers in cellular signal cascades pertinent to inflammation, cell proliferation, transformation, protein kinesis, and cytoskeletal assembly (4). Minute quantities are found in cells and biochemical studies to determine the cellular targets of the 3-PPI, their metabolic fate, and their roles in the cell cycle have been handicapped because 3-PPI have not been available. Methods for synthesis of 3-PPI have been sought recently (5). These prior art methods suffer from some unique and common problems related respectively to the choice of starting materials for the myo-inositol as well as the diacylglycero-lipid moieties in the 3-PPI. In contrast with the present invention, all start with sn-1,2-diacylglycerols as the lipid moiety in the 3-PPI, and consequently are prone to problems of poor chemical stability endemic to 1,2-diacylglycerols. The latter isomerize readily via neighboring O-acyl migration to equilibrium mixtures comprising the 1,2-, 1,3- and 2,3-diacylglycerols (6). This equilibration is tantamount to racemization which is virtually complete for sn-1,2-di(short-chain)fattyacylglycerols. Therefore, resulting 3-PPI may contain racemic 1,2-2,3- and 1,3-difattyacyl structures, especially with hexanoyl and related short-chain fattyacyls.
SUMMARY OF THE INVENTION
Accordingly, it is a principal object of the present invention to provide novel general approaches to synthesis, including novel starting materials, reaction sequences, and novel intermediate compounds, for preparation of the 3-PPI and structural analogues, all of unambiguous structure and absolute stereochemistry in the myo-inositol as well as the sn-glycerol moieties. The present starting materials, reaction sequences, and intermediate compounds, individually and collectively, have utility as materials and processes for obtaining the 3-PPI. The 3-PPI and analogues, in turn, have utility not only as research reagents but also for the development of diagnostics and therapeutics based on the roles of 3-PPI in intracellular signalling. In similar investigations of the biological roles of other bioactive compounds, analogues with reporter groups such as fluorescent tags, are often useful, and so intermediates of 3-PPIs conjugatable to reporter groups are sought.
Broadly, the invention embodies two complementary strategic approaches, and the starting materials and intermediates involved in each, based respectively on (i) synthesis from novel enantiomerically pure myo-inositol derivatives and phosphatidic acids, and (ii) partial synthesis by regioselective-3-phosphorylation of preformed phosphatidylinositol or derived phosphates.
According to one embodiment of the invention, synthesis is carried out by a novel unified approach which is suitable for facile synthesis of all cellular PtdIns-3-phosphates. It is based on the retrosynthetic analysis shown for PtdIns(3,4,5)P 3 as an example in FIG. 2 . The approach has several novel features. One, it uses 1D-1,2:4,5-di-O-cyclohexylidene-3-O-allyl-myo-inositol (−)-1 as purposely designed starting material and 1D-1,2-O-cyclohexylidene-3-O-allyl-6-O-benzyl-myo-inositol (+)-3 as a key myo-inositol synthon. Two, it incorporates strategic O-protection by a sequentially invariant removal of allyl, 4-methoxybenzyl, and benzyl protecting groups from the inositol hydroxyls destined to appear in the target structures as phosphate, phosphatidyl, and free hydroxyl respectively. Three, it employs preformed 1,2-di-O-fattyacyl-sn-glycero-3-phosphoric acid (sn-3-phosphatidic acid) as the lipid synthon for coupling to appropriately O-protected myo-inositol by a phosphodiester condensation. The sn-3-phosphatidic acid are relatively stable compounds with well established absolute stereochemistry, and their application in the present invention avoids the problems of structural and stereochemical isomerization associated with the application of sn-1,2-fattyacylglycerol in the prior art. As a consequence, the approach uniquely provides unambiguous structural and stereochemical control in the myo-inositol as well as the sn-glycerol moieties, and is applicable for both short-and long-chain fattyacyl types (7). Compared with the long-chain types, the short-chain phosphoinositides are considered to be more useful in biochemical investigations (3, 4). The phosphodiester condensation products are substrates for lipolytic enzyme phospholipase A 2 and thus are valuable for incorporating additional useful structural features at a relatively late stage in synthesis. For instance, after lipolysis followed by esterification to introduce (ω-amino-fattyacyls at the sn-glycerol-2 position, the ω-amino group may be conjugated to fluorescent and related reporter groups. The aforementioned attributes are useful and these distinguish the present invention from related literature methods cited above (5).
According to another embodiment of the invention, partial synthesis is based on the retrosynthetic analysis illustrated for PtdIns(3,4,5)P 3 from PtdIns(4,5)P 2 in FIG. 3 . It comprises the regioselective 3-phosphorylation of preformed phosphatidylinositol or derived phosphates but lacking the D-3-phosphate, for the synthesis of the 3-PPI. The preformed PtdIns obtained from natural plant or animal cell sources contain (poly)unsaturated fattyacyls. Using such natural or the corresponding synthetic phosphatidylinositols with unsaturated fattyacyls as the starting materials for 3-phosphorylation as disclosed in the present invention provides methods for the synthesis of 3-PPI containing (poly)unsaturated fattyacyls. These 3-PPI have special physical properties such as lower chain melting transitions for the fattyacyls than for the corresponding saturated fattyacyls, and special bioactivity related to the number, location, and stereochemistry of the double bonds in the fattyacyl chain, and so are desirable. These 3-PPI cannot be prepared by the literature methods (5).
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates the structure and stereochemistry of the D-3-phosphorylated phosphoinositides (the 3-PPI).
FIG. 2 illustrates retrosynthetic analysis of the D-3-phosphorylated phosphoinositide PtdIns(3,4,5)P 3 for synthesis from sn-3-phosphatidic acid and a selectively substituted myo-inositol.
FIG. 3 illustrates retrosynthetic analysis of the D-3-phosphorylated phosphoinositide PtdIns(3,4,5)P 3 for synthesis from PtdIns(4,5)P 2 .
FIG. 4 Preparation of 1D-1,2:4,5-di-O-cyclohexylidene-3-O-allyl-myo-inositol (−)-1 starting material.
FIG. 5 Preparation and structure of key myo-inositol intermediates.
FIGS. 6A, 6 B and 6 C Synthesis of selectively protected myo-inositol synthons and PtdIns(3,4,5)P 3 .
FIG. 7A and 7B Partial Synthesis of PtdIns(3,4,5)P 3 from PtdIns(4,5)P 2 .
FIG. 8 PtdIns-benzyl ester, starting material for phosphorylation to PtdIns(3)P.
DETAILED DESCRIPTION OF THE INVENTION
Synthesis from myo-Inositol
The cellular 3-PPI all belong to the 1D-myo-inositol stereochemical series. The present approach to synthesis uses 1D-1,2:4,5-di-O-cyclohexylidene-3-O-allyl myo-inositol (−)-1 as purposely designed starting material and 1D-1,2-O-cyclohexylidene-3-O-allyl-6-O-benzyl-myo-inositol (+)-3 as a key myo-inositol synthon. For the preparation of the starting material (FIG. 4 ), reaction of highly purified (±)-1,2:4,5-di-O-cyclohexylidene-myo-inositol (8) and allyl bromide in DMF at 0-5° C. with gradual addition of NaH as a new protocol providing kinetic control, resulted in highly selective mono-allylation at 3-OH, such that (±)-1,2:4,5-di-O-cyclohexylidene-3-O-allyl-myo-inositol 1a (9) was obtained pure by crystallization without need for liquid chromatography. Esterification of the (±)-3-O-allyl derivative using (1s)-(−)-camphanic acid chloride/NEt 3 and separation of the diastereomeric esters by MPLC on silica and crystallization from acetone gave each of the two diastereomers (>80% yield) in >98% purity as judged by TLC, HPLC and 1 H NMR. Alkali catalyzed hydrolysis of the more polar of the two diastereomeric esters 1b, [α] D −16.5°, (c 1.5 CHCl 3 ) yielded (−)-1, [α] D −9.5°, (c 1.0, CHCl 3 ). Similar treatment of the less polar diastereomer 1c, [α] D −2.03°, (c 1.0 CHCl 3 ) gave (+)-1d, [α] D +9.17°, (c 0.5, CHCl 3 ). The absolute configuration of each enantiomer was established as follows. Reaction of (−)-1 successively with (i) hot HOAc—H 2 O to remove both the O-cyclohexylidene protecting groups, and (ii) an excess of NaH and BnBr in anhydrous DMF, gave 1D-3-O-allyl-1,2,4,5,6-penta-O-benzyl-myo-inositol, [α] D −2.3°, (c 1.0, CHCl 3 ). Treatment of the O-benzyl derivative with potassium tert-butoxide in warm DMSO to isomerize O-allyl to O-|prop-1′-enyl| followed by methanolic HCl (10) yielded (+)-1,2,4,5,6-penta-O-benzyl-myo-inositol, [α] D +11.2°, (c 1.1, CHCl 3 ). The absolute configuration of (+)-1,2,4,5,6-penta-O-benzyl-myo-inositol has been unequivocally assigned as 1D-1,2,4,5,6-penta-O-benzyl-myo-inositol (11). Therefore, the absolute configuration of (−)-1 is derived unambiguously as 1D-1,2:4,5-di-O-cyclohexylidene-3-O-allyl-myo-inositol. Similarly, (+)-1d is assigned the 1L-configuration.
In the first step of synthesis (FIG. 5 ), reaction of (−)-1 with excess BnBr/NaH in DMF at R.T. overnight gave in quantitative yield its 6-O-benzyl derivative (−)-2 [α] D −51.6° (c 1.1, CHCl 3 ). Transketalization under kinetic control by reaction of (−)-2 with ethylene glycol (1.2 mole)/catalytic p-TSA in CH 2 Cl 2 at R.T. for 3 hr. gave the key synthon (+)-3, yield 81%, [α] D +26.2° (c 1.0, CHCl 3 ). Reaction of (+)-3 in DMF at R.T. for 8 hr. with 1.2 moles of allyl bromide and NaH yielded the complete set of intermediates required for all four known PtdIns-3-phosphates. By chromatography on silica, the following pure compounds were obtained (FIG. 5 ): in 28% yield, 1D-1,2-O-cyclohexylidene-3,4,5-tri-O-allyl-6-O-benzyl-myo-inositol (−)-(4) [α] D −11.3° (c 1.0, CHCl 3 ), Lit. [α] D −9.2°, (c 1.5, CHCl 3 ) (12); in 26% yield, 1D-1,2-O-cyclohexylidene-3,4-di-O-allyl-6-O-benzyl-myo-inositol (+)-(4a), [α] D +11.6° (c 0.82, CHCl 3 ); in 24% yield, 1D-1,2-O-cyclohexylidene-3,5-di-O-allyl-6-O-benzyl-myo-inositol (−)-(4b) [α] D −13.5° (c 0.96, CHCl 3 ); and, in 22% yield, unchanged starting material (+)-3. The overall utilization of (+)-3 is 90% considering that the recovered compound is converted into (−)-4e in the next step (complete benzylation). Alternatively, reaction of (+)-3 as above but using an excess of allyl bromide/NaH yielded (−)-(4) in quantitative yield. Compounds (+)-4a, (−)-4b, and (+)-3 each were treated with an excess of BnBr and NaH in DMF at R.T. for 16 hr. and gave quantitative yields of the fully O-protected myo-inositols (−)-4c [α] D −5.6° (c 1.43, CHCl 3 ), (−)-4d [α] D −21.3° (c 1.23, CHCl 3 ), and (−)-4e [α] D −25.3° (c 2.0, CHCl 3 ).
Compounds (−)-4, (−)-4c, (−)-4d, and (−)-4e are intermediates respectively for the synthesis of PtdIns(3,4,5)P 3 . PtdIns(3,4)P 2 , PtdIns(3,5)P 2 , and PtdIns(3)P, by the sequence of reactions illustrated for PtdIns(3,4,5)P 3 series (FIG. 6A, 6 B and 6 C). On heating at 95° C. for 3 hr. with acetic acid-water (80:20), (−)-4 lost the O-cyclohexylidene protection and gave the 1,2-diol (−)-5 [α] D −16.2° (c 1.0, CHCl 3 ), Lit. [α] D −10° (c 2, CHCl 3 ). Reaction of (−)-5 with Bu 2 SnO in toluene with azeotropic removal of H 2 O, rotary evaporation, solvent change to DMF and treatment with 4-methoxybenzyl chloride at 50° C. for 8 hr. provided high selectivity for reaction at the equatorial 1-OH over axial 2-OH (91:9) and gave after chromatography on silica (+)-6 [α] D +6.8° (c 1.0, CHCl 3 ). On treatment with excess BnBr/NaH in DMF at R.T. for 16 hr., (+)-6 produced 1D-1-O-(4′-methoxybenzyl)-3,4,5-O-tri-O-allyl-2,6-di-O-benzyl-myo-inositol (−)-7 [α] D −8.0° (c 1.0, CHCl 3 ). Compound (−)-7 incorporates 3 types of blocking groups arranged for selective and successive deblocking and liberation of hydroxyls, from O-allyls for dibenzylphos-phorylation, from the 1-O-(4′-methoxybenzyl) for phosphatidylation, and the O-benzyls to regenerate the free hydroxyls in the target structure. Reaction of (−)-7 with 10% Pd—C in methanol-acetic acid-water (98:2:0.1) under reflux caused complete O-deallylation to yield (−)-8 [α] D −7.5° (c 1.0, CHCl 3 ). Reaction of (−)-8 in DMF with NaH and tetrabenzyl pyrophosphate (13) produced the 3,4,5-tris-O-(dibenzyl phosphate) derivative (−)-9 |α| D −9.5° (c 2.9, CHCl 3 ). The treatment of (−)-9 with DDQ in CH 2 Cl 2 yielded the 1D-2,6-O-dibenzyl-myo-inositol 3,4,5-tris-(dibenzylphosphate) (−)-10 [α] D −6.5° (c 0.2, CHCl 3 ), a key intermediate for the preparation of PtdIns(3,4,5)P 3 . The same sequence of reactions as described above for compound (−)-4 (FIG. 6A, 6 B and 6 C), carried out with (−)-4c, (−)-4d, and (−)-4e, gave 10c, 10d, and 10e as the corresponding intermediates respectively for the preparation of PtdIns(3,4)P 2 , PtdIns(3,5)P 2 , and PtdIns(3)P.
The next step in this synthesis is the condensation of the selectively protected 1D-myo-inositol derivative (−)-10, 10c, 10d, or 10e with the lipid sn-3-phosphatidic acid. Methods for the preparation of sn-3-phosphatidic acids are well known in the literature and in fact sn-phosphatidic acids with a variety of fattyacyls are available from commercial sources.
Reaction of (−)-10 with 1,2-dihexadecanoyl-sn-glycero-3-phosphoric acid (14) (13) in anhydrous pyridine and triisopropyl-benzenesulfonyl chloride as condensing agent (15) at R.T. for 18 hr. gave the phosphodiester product 1D-1-(1′,2′-dihexadecanoyl-sn-glycero-3′-phospho)-myo-inositol-3,4,5-tris-(dibenzylphosphate) (+)-11 [α] D +4.0° (c 0.3, CHCl 3 ). Hydrogenolysis of (+)-11 in ethanol using Pd-black and H 2 gas at 45 psi yielded 1-(1′,2′-dihexadecanoyl-sn-glycero-3′-phospho)-myo-inositol-3,4,5-triphosphate, PtdIns(3,4,5)P 3 , (+)-12 [α] D +5.8° (c 0.2, CHCl 3 —MeOH—H 2 O, 2:1:0.1), Lit. [α] D +3.7 (c 0.5, CHCl 3 ). 5b
The present choice of preformed sn-3-phosphatidic acid as the lipid synthon merits special comment. It contrasts with the related synthesis which all utilize sn-1,2-diacylglycerol in tetrazole-catalyzed reaction with (benzyloxy)bis(N,N-diisopropylamino)-phosphine, BnOP (NCH(CH 3 ) 2 ) 2 , or related phosphoramidite (5). The use of sn-3-phosphatidic acid prepared from natural sn-glycero-3-phosphocholine avoids problems endemic to the chemistry of 1,2-diacylglycerol. The latter isomerize readily via neighboring O-acyl migration to equilibrium mixtures comprising the 1,2-, 1,3- and 2,3-diacylglycerols (16), and indeed 1,3-dihexadecanoyl-glycerol is detected by TLC in the tetrazole-catalyzed reaction of sn-1,2-dihexadecanoylglycerol with BnOP(NCH(CH 3 ) 2 ) 2 (17). This equilibration is tantamount to racemization which is virtually complete for the reaction of sn-1,2-dihexanoylglycerol. Such propensity for racemization is absent from sn-3-phosphatidic acids. This is critically important for synthesis of PtdIns-3-phosphates with hexanoyl or shorter chain acyls.
In contrast with the long chain acyl derivatives which are self-aggregating in water, the short chain analogues are expected to form monomeric solutions and are considered advantageous as biochemical probes (3,4]. The absolute configuration of sn-3-phosphatidic acids is well established, and that of the key myo-inositol synthon is derived unequivocally based on their preparation from (−)-1. The one-step esterification of the sn-3-phosphatidic acid and the myo-inositol synthon in stereochemically innocuous. Thus, the present approach ensures that the structural and stereochemical integrity of the lipid and the myo-inositol synthons is conveyed faithfully and unambiguously to the target phosphatidylinositol-3-phosphates.
Partial Synthesis of PtdIns(3,4,5)P 3 from PtdIns(4,5)P 2
The partial synthesis of 3-PPI by regioselective phosphorylation at 3-OH in preformed phosphoinositides (FIG. 7) is illustrated by the regioselective phosphorylation at 3-OH of PtdIns(4,5)P 2 . A 2,3-dibutylstannylene derivative was formed in situ by reaction with dibutyltin oxide followed by reaction with dibenzyl chlorophosphate without overt blocking of other alcoholic hydroxyls in the molecule. Purification followed by removal of benzyl protection by hydrogenation gave PtdIns(3,4,5)P 3 , identical in TLC comparison with the product (+)-12 but different from PtdIns(2,4,5)P 3 obtained by unequivocal synthesis from 1D-1-(1′,2′-dihexadecanoyl-sn-glycero-3′-phospho)-3,6-dibenzyl-myo-inositol-4,5-bis(dibenzylphosphate).
In an alternative approach, the reaction at room temperature between PtdIns-benzyl ester (FIG. 8) in anhydrous pyridine with 2-trichloroethylphosphoric acid using triisopropyl-benzenesulphonyl chloride gave a mixture. With 0.1 mol proportion of 2-trichloroethylphosphoric acid, a single product was formed. On treatment with activated zinc and acetic acid to remove the 2-trichloroethyl protecting group, followed by NaI in anhydrous acetone for anionic debenzylation, a mixture of unchanged PtdIns and PtdIns (3)P was obtained, and separated by liquid chromatography on aminiopropylsilica column.
The product distribution in the phosphorylation of PtdIns-benzyl ester described above was controlled experimentally by varying the mol proportion of the reactants to obtain concurrently all possible 3-PPI structures as phosphoinositide “libraries”. The individual 3-PPI as well as the “libraries” have immense potential value as probes in bioactivity screens. Other direct or indirect phosphorylation reagents and protocols may be utilized for the phosphorylation step.
EXAMPLE 1
1D-1-(1,2-Dihexadecanoyl-sn-glycero-3′-phospho)-myo-inositol-3,4,5-triphosphate, PtdIns(3,4,5)P 3 , (+)-12
(±)-1:2:4,5-Di-O-cyclohexylidene-3-O-allyl-myo-inositol (1a)
To a solution of 105 g (0.309 mol) of DL-1,2:4,5-di-O-cyclohexylidene-myo-inositol in 400 ml DMF, 26 ml (0.30 mol) allyl bromide (from a dropping funnel) was added under N 2 at 0-5° C. and 16.6 g (0.415 mol, 40% oil) NaH was added gradually. Reaction was left at R.T. overnight. TLC (solvent: CH 2 Cl 2 /ether 95:5) showed D,L-1:2:4,5-Di-O-cyclohexylidene-3-O-allyl-myo-inositol as the major product. Excess NaH was destroyed with DH 2 O at 0-5° C. DMF and H 2 O were evaporated. Residue was extracted with CHCl 3 , dried, filtered and concentrated. Crude reaction product crystallized three times from acetone gave pure DL-1:2:4,5-di-O-cyclohexylidene-3-O-allyl-myo-inositol (1a). (76.3 g, 65%).
1D-1,2:4,5-Di-O-cyclohexylidene-3-O-allyl-6-O-camphanate-myo-inositol (1b)
To a solution of 25.5 g (0.067 mol) of D,L-1:2:4,5-di-O-cyclohexylidene-3-O-allyl-myo-inositol (1a) in 200 ml CH 2 Cl 2 , 10 ml triethylamine and 16.0 g (0.074 mol) of (1S)-(−)-camphanic acid chloride in CH 2 Cl 2 (from a dropping funnel) were added at 0-5° C. Reaction was left at R.T. overnight. TLC (solvent: hexane/ethyl acetate 80:20) showed reaction was complete. Reaction was neutralized, extracted, dried, filtered and concentrated. Crude reaction was chromatographed on silica gel, 200-425 MESH) eluted with a gradient of hexane/CH 2 Cl 2 /ethyl acetate followed with crystallization gave pure 1D-1,2:4,5-di-O-cyclohexylidene-3-O-allyl-6-O-camphanate-myo-inositol (1b). (37.5 g, 100%) [α] D =−16.5° (c 1.5, CHCl 3 ).
1D-1,2:4,5-Di-O-cyclohexylidene-3-O-allyl-myo-inositol (1)
To 14.2 g (25.3 mmol) of 1D-1,2:4,5-di-O-cyclohexylidene-3-O-allyl-6-O-camphanate-myo-inositol (1b), 500 ml ether, 500 ml ethanol, 100 mg (0.29 mmol) of tetrabutyl ammonium hydrogen sulfate and 3.35 g (79.8 mmol) lithium hydroxide (in 30 ml DH 2 O, from a dropping funnel) were added. Reaction was left at R.T. overnight. TLC (solvent: CH 2 Cl 2 /ether 95:5) showed reaction was complete. Ether and ethanol were evaporated. Residue was extracted, dried, filtered and concentrated. Crude reaction was passed through a short column, eluted with CHCl 3 , gave pure 1D-1,2:4,5-di-O-cyclohexylidene-3-O-allyl-myo-inositol (1). (9.6 g, 100%) [α] D =−9.5° (c 1.0, CHCl 3 ).
1D-1,2:4,5-Di-O-cyclohexylidene-3-O-allyl-6-O-benzyl-myo-inositol (2)
To a solution of 8.64 g (23 mmol) of 1D-1,2:4,5-di-O-cyclohexylidene-3-O-allyl-myo-inositol (1) in 180 ml DMF, 3.2 g (80 mmol, 40% oil) NaH and 4 ml (33.6 mmol), from a dropping funnel) benzyl bromide were added under N 2 at 0-5° C. Reaction was left at R.T. overnight. TLC (slovent: hexane/ethyl acetate 80:20) showed reaction was complete. Excess NaH was destroyed with DH 2 O at 0-5° C. DMF and H 2 O were evaporated, residue was extracted, dried, filtered and concentrated. Crude reaction was chromatographed on silica gel (200-425 MESH) eluted with a gradient of hexane/ethyl acetate gave pure 1D-1,2:4,5-di-O-cyclohexylidene-3-O-allyl-6-O-benzyl-myo-inositol (2). (10.8 g, 100%) [α] D =−51.6° (c 1.1, CHCl 3 ).
1D-1,2-O-Cyclohexylidene-3-O-allyl-6-O-benzyl-myo-inositol (+)-3
To a solution of 6.1 g (13.0 mmol) of 1D-1,2:4,5-di-O-cyclohexylidene-3-O-allyl-6-O-benzyl-myo-inositol (2) in 65 ml CH 2 Cl 2 (dried over P 2 O 5 for 1 hr), 0.5 ml (8.97 mmol) of ethylene glycol and 48 mg (0.252 mmol) of p-toluenesulfonic acid were added under N 2 at R.T. After 2 hrs, TLC (solvent: CH 2 Cl 2 /acetone 95:5, product Rf: 0.2) showed reaction was complete. 5 drops of triethylamine, 15 drops of DH 2 O and 1.0438 g (11.9 mmol) of KHCO 3 were added to the flask. Reaction was later diluted with 200 ml CH 2 Cl 2 , filtered, dried, filtered again and concentrated. Crude reaction was chromatographed on silica gel (200-425 MESH) eluted with a gradient of hexane/ethyl acetate gave pure 1D-1,2-O-cyclohexylidene-3-O-allyl-6-O-benzyl-myo-inositol (3). (4.1 g, 81%) [α] D =+26.2° (c 1.0, CHCl 3 ). 1 H-NMR (300 MHz, CDCl 3 ): δ ppm 1.54-1.71 (br m, 10H, cyclohex-), 2.7 (br, 2H, OH), 3.38 (ψt, J 9.6 Hz, 1H, H-5), 3.41-3.56 (m, 2H, H-3 & H-6), 3.89 (ψt, J 9.4 Hz, 1H, H-4), 4.01-4.15 (m, 1H, H-1), 4.16-4.28 (m, 2H, CH 2 —C═), 4.38 (dd, J 4.2, 4.2 Hz, 1H, H-2), 4.81 (q, 2H, J 11.4 & 91.8, Phenyl-CH 2 ), 5.19-5.34 (m, 2H, CH 2 ═C), 5.89-6.03 (m, 1H, —CH═C), 7.24-7.38 (m, 5H, C 6 H 5 ). In diacetate of (+)-3, 3.89 H-4, 3.38 H-5 signals shift to 5.30 and 4.99.
1D-1,2-O-Cyclohexylidene-3,4,5-tri-O-allyl-6-O-benzyl-myo-inositol (4)
To a solution of 2.4 g (6.1538 mmol) of 1D-1,2-O-cyclohexylidene-3-O-allyl-6-O-benzyl-myo-inositol (3) in 50 ml DMF, 1.24 g (31 mmol, 40% oil) of NaH and 2 ml (23.0 mmol) of allyl bromide were added under N 2 at 0-5° C. Reaction was left at R.T. overnight. TLC (solvent: hexane/ethyl acetate 80:20) showed reaction was complete. Excess NaH was destroyed with DH 2 O at 0-5° C. Reaction was extracted with CHCl 3 , dried, filtered and concentrated. Crude reaction was chromatographed on silica gel (200-425 MESH) eluted with a gradient of hexane/CH 2 Cl 2 /ethyl acetate gave pure1D-1,2-O-cyclohexylidene-3,4,5-tri-O-allyl-6-O-benzyl-myo-inositol (4). (2.9 g, 100%) [α] D =−11.3° (c 1.0, CHCl 3 ).
Reaction of (+)-3 in DMF at R.T. for 8 hr. with 1.2 moles of allyl bromide and NaH yielded the complete set of intermediates required for all four known PtdIns-3-phosphates. By chromatography on silica, the following pure compounds were obtained (FIG. 5 ): in 28% yield, 1D-1,2-O-cyclohexylidene-3,4,5-tri-O-allyl-6-O-benzyl-myo-inositol (−)-(4) [α] D −11.3° (c 1.0, CHCl 3 ), Lit. [α] D −9.2°, (c 1.5, CHCl 3 ); in 26% yield, 1D-1,2-O-cyclohexylidene-3,4-di-O-allyl-6-O-benzyl-myo-inositol (+)-(4a), [α] D +11.6° (c 0.82, CHCl 3 ); in 24% yield, 1D-1,2-O-cyclohexylidene-3,5-di-O-allyl-6-O-benzyl-myo-inositol (−)-(4b) 10 [α] D −13.5° (c 0.96, CHCl 3 ); and, in 22% yield, unchanged starting material (+)-3. The structures of the two monobenzyl derivatives were established by NMR spectra below.
(+)-4a, 1 H-NMR (300 MHz, CDCl 3 ): δ ppm 1.17-1.74 (br m, 10H, cyclohex-), 2.64 (br, 1H, OH), 3.44 (ψt, J 9.5 Hz, 1H, H-5), 3.56-3.68 (m, 2H, H-3 and H-6), 4.12 (ψt, J 5.9 Hz, 1H, H-4), 4.17-4.21 (m, 1H, H-1), 4.17-4.32 (m, 4H, 2 CH 2 —C═), 4.35 (dd, J 4.2, 4.2 Hz, 11H, H-2), 4.80 (q, 2H, J 12.0 and 57.0, Phenyl-CH 2 ), 5.13-5.32 (m, 4H, 2 CH 2 ═C), 5.85-5.97 (m, 2H, −2 CH═C), 7.18-7.38 (m, 5H, C 6 H 5 ). In the monoacetate of (+)-4a, the 3.44 H-5 signal shifts downfield to 4.93.
The 1 H-NMR of (−)-4c, the O-benzyl derivative of (+)-4a, was identical with the spectrum of DL-4c prepared by complete benzylation, selective removal of 3,4-O-cyclohexylidene, and complete allylation from DL-1,2:3,4-di-O-cyclohexylidene-myo-inositol (Garegg, P. J; Iversen, T.; Johansson, R.; Lindberg, B. Carbohydr. Res. 1984, 130, 322-326)].
(−)-(4b) 1 H-NMR (300 MHz, CDCl 3 ): δ ppm 1.34-1.72 (br m, 10H, cyclohex-), 2.59 (br, 1H, OH), 3.16 (ψt, J 9.4 Hz, 1H, H-5), 3.48 (q, J 9.6 and 3.7, 1H, H-3), 3.62 (ψt, J 6.6 Hz, 1H, H-6), 3.93 (ψt, J 9.5 Hz, 1H, H-4), 4.11 (q, J 5.2 and 7.0 Hz, 1H, H-1), 4.17-4.38 (m, 4H, 2 CH 2 —C═), 4.41 (dd, J 4.1, 1.1 Hz, 1H, H-2), 4.80 (q, 2H, J 11.4 and 35.4, Phenyl-CH 2 ), 5.13-5.34 (m, 4H, 2 CH 2 ═C), 5.87-5.98 (m, 2H, 2 —CH═C), 7.23-7.38 (m, 5H, C 6 H 5 ). In the monoacetate of (−)-4b, 3.93 H-4 signal is shifted downfield to 5.33 and the latter shows spin connectivity to 3.28 H-5 and 3.58 H-3 signals observed by selective irradiation at 5.58 and 1 H COSY (500 MHz).
1D-3,4,5-Tri-O-allyl-6-O-benzyl-myo-inositol (5)
To 4.4 g (9.36 mmol) of 1D-1,2-O-cyclohexylidene-3,4,5-tri-O-allyl-6-O-benzyl-myo-inositol (4), 80% aqueous acetic acid was added, reaction was heated at 90° C. for several hrs. TLC (solvent: CHCl 3 /MeOH 95:5) showed the conversion was complete. Reaction was then neutralized (with KHCO 3 ),extracted (with CHCl 3 ), dried, filtered and concentrated. Crude reaction was chromatographed on silica gel (200-425 MESH) eluted with a gradient of CHCl 3 /MeOH to give pure 1D-3,4,5-tri-O-allyl-6-O-benzyl-myo-inositol (5). (3.65 g,100%) [α] D =−16.2° (c 1.01 CHCl 3 ).
1D-3,4,5-Tri-O-allyl-6-O-benzyl-1-(p-methoxybenzyl)-myo-inositol (6)
A mixture of 3.65 g (9.3 mmol) of 1D-3,4,5-tri-O-allyl-6-O-benzyl-myo-inositol (5), 2.65 g (1.06 mmol) of Bu 2 SnO and 50 ml toluene was heated under reflux, with azeotropic removal of water, for 2 hrs. Mixture was heated under reflux for 1 more hr after adding 150 mg (0.44 mmol) of tetrabutyl ammonium hydrogen sulfate. Toluene was then evaporated and 50 ml DMF along with 2.55 ml (1.88 mmol) of 4-methoxybenzyl chloride were added. Reaction was heated at 108-110° C. for several hrs. TLC (solvent: CH 2 Cl 2 /acetone 95:5 product Rf:0.4) showed reaction was complete. DMF was evaporated and residue was extracted, dried, filtered and concentrated. Crude reaction was chromatographed on silica gel (200-425 MESH) eluted with a gradient of hexane/CH 2 Cl 2 /ethyl acetate gave pure 1D-3,4,5-tri-O-allyl-6-O-benzyl-1-(p-methoxybenzyl)-myo-inositol (6).(3.99 g, 84%) [α] D =+6.8° (c 1.0, CHCl 3 ). (+)-6 1 H-NMR (300 MHz, CDCl 3 ): δ ppm 2.54 (br, 1H, OH), 3.05 (dd, J 2.4 and 10.0 Hz, 1H, H-1), 3.13-3.23 (m, 2H, H-3 and H-6), 3.23-3.77 (m, 1H, H-5), 3.73 (s, 3H, OCH 3 ), 3.87 (ψt, J 10.1 Hz, 1H, H-4), 3.97-3.99 (m, 1H, H-2), 4.20-4.28(m, 6H, 3 CH 2 ═C), 4.43-4.80(m, 4H, 2 Phenyl-CH 2 ), 5.05-5.25 (m, 6H, 3 CH 2 ═C), 5.77-5.95 (m, 3H, 3 —CH═C), 6.75-6.79 (m, 2H, aromat-), 7.13-7.35 (m, 7H, aromat-). In the monoacetate of (+)-6, the 3.97-3.99 H-2 signal shifted to 5.56 ppm.
1D-3,4,5-Tri-O-allyl-2,6-di-O-benzyl-1-(p-methoxybenzyl)-myo-inositol (7)
To a solution of 2.728 g (5.68 mmol) of 1D-3,4,5-tri-O-allyl-6-O-benzyl-1-(p-methoxybenzyl)-myo-inositol (6) in 20 ml DMF, 0.623 g (15.57 mmol, 40% oil) NaH, 0.66 ml (5.55 mmol) of benzyl bromide (from a dropping funnel) were added under N 2 at 0-5° C. Reaction was left at R.T. under N 2 with stirring overnight. Excess NaH was destroyed with DH 2 O at 0-5° C. DMF and H 2 O were evaporated. Crude reaction was chromatographed on silica gel (200-425 MESH) eluted with a gradient of hexane/CH 2 Cl 2 /ethyl acetate gave pure 1D-3,4,5-tri-O-allyl-2,6-di-O-benzyl-1-(p-methoxybenzyl)-myo-inositol (7).(3.4 g,100%) [α] D =−7.5° (c 1.0, CHCl 3 ).
1D-2,6-Di-O-benzyl-1-(p-methoxybenzyl)-myo-inositol (8)
To a solution of 437.8 mg (0.7296 mmol) of 1D-3,4,5-tri-O-allyl -2,6-di-O-benzyl-1-(p-methoxybenzyl)-myo-inositol (7) in 4 ml DMSO,1.45 g (12.921 mmol) of potassium tert-butoxide was added. Reaction was heated at 55° C. with N 2 atmosphere for several hrs. TLC (solvent: hexane/ethyl acetate 85:15 develop twice) showed the starting material had convered into the corresponding propenyl. Reaction was neutralized with 0.1M HCl to PH=7, extracted, dried, filtered and concentrated. MeOH/HOAC (95:5, 8 ml) was added to the first step product, reaction was heated at 70° C. for 2½ hrs. TLC(solvent: CHCl 3 /MeOH/NH 4 OH 90:10:1) showed the desired product. Reaction was then filtered and concentrated. Crude reaction was chromatographed on silica gel (200-425 MESH) eluted with a gradient of CHCl 3 /MeOH gave pure 1D-2,6-di-O-benzyl-1-(p-methoxybenzyl)-myo-inositol (8). (263 mg, 75%) [α] D =−7.5° (c 1.0, CHCl 3 ).
1D-2,6-Di-O-benzyl-3,4,5-tris-dibenzylphosphanate-1-(p-methoxybenzyl)-myo-inositol (9)
To a solution of 169.9 mg (0.3539 mmol) of 1D-2,6-di-O-benzyl-1-(p-methoxybenzyl)-myo-inositol (8) in 10 ml CH 2 Cl 2 (dried over P 2 O 5 ), 297.5 mg (4.247 mmol) of 1H tetrazole and 0.7 ml (2.1237 mmol) of N,N-diisopropyl dibenzylphosphoramidite were added, reaction was stirred at R.T. for 15 mins. A −40° C. cold bath was prepared and 770 mg(4.462 mmol) of 3-chloroperoxybenzoic acid was added to the reaction in the cold bath, reaction was stirred at 0° C. for 15 mins. TLC (solvent: hexane/ethyl acetate 60:40) showed the reaction was complete. 250 ml of 20% Na 2 SO 3 solution was added, reaction was stirred at R.T. for 40 mins. NaI test was checked (negative). Reaction was then extracted with CH 2 Cl 2 , washed with saturated NaHCO 3 , followed with saturated NaCl solution. CH 2 Cl 2 layer was dried, filtered and concentrated. Crude reaction was chromatographed on silica gel (200-425 MESH) eluted with a gradient of hexane/ethyl acetate gave pure 1D-2,6-di-O-benzyl-3,4,5-tris-dibenzylphosphate-1-(p-methoxybenzyl)-myo-inositol (9).(356.7 mg, 80%) [α] D =−9.5° (c 2.9, CHCl 3 ).
1D-2,6-Di-O-benzyl-3,4,5-tris-dibenzylphosphate-myo-inositol (10)
To 407.2 mg (0.33 mmol) of 1D-2,6-di-O-benzyl-3,4,5-tris-dibenzylphosphate-1-(p-methoxybenzyl)-myo-inositol (9), 150.3 mg (0.662 mmol) of 2,3-dichloro-5,6-dicyano-1, 4-benzoquinone, 12 ml CH 2 Cl 2 and 4 drops of DH 2 O were added. Reaction was stirred at R.T. for 1 hr. TLC (solvent: CHCl 3 /ether 80:20) showed reaction was complete. Reaction was diluted with CH 2 Cl 2 , washed with cold saturated NaHCO 3 solution, followed with cold saturated NaCl solution, CH 2 Cl 2 layer was dried, filtered and concentrated. Crude reaction was chromatographed on silica gel (200-425 MESH), eluted with a gradient of CHCl 3 /ether gave pure 1D-2,6-di-O-benzyl-3,4,5-tris-dibenzylphosphate-myo-inositol (10). (335.9 mg, 89%) [α] D =−6.5° (c 0.2, CHCl 3 ).
1D-1-(1′,2′-dihexadecanoyl-sn-glycero-3′-phospho)-2,6-dibenzyl-myo-inositol-3,4,5-tris (dibenzylphosphate) (+)-11
A solution of the monohydroxy derivative (−)-1O (0.0578 g), 1,2-dihexadecanoyl-sn-glycero-3-phosphoric acid (sn-3-phosphatidic acid-dihexadecanoyl, 13) (0.0761 g) and tri-isopropylbenzenesulfonyl chloride (0.0685 g) in anhydrous pyridine (0.75 ml) was stirred at r.t. for 2.5 hr. Water (1 ml) was added, the mixture stirred for 1 hr and solvent evaporated in a vacuo. The residue, chromatographed on silicagel (HPLC) eluted with a gradient of CHCl 3 —CH 3 OH gave the major product 1D-1-(1′,2′-dihexadecnoyl-sn-glycero-3′-phospho)-2,6-dibenzyl-D-myo-inositol-3,4,5-tris (dibenzylphosphate) (+)-11, [α] D +4.0° (c 0.3, CHCl 3 ), (0.0685 g, 69%).
1D-1-(1′,2′-Dihexadecanoyl-sn-glycero-3′-phospho)-myo-inositol-3,4,5-trisphosphate, PtdIns(3,4,5)P 3 , (+)-12
Compound (+)-11 (0.0437 g) and Pd black catalyst (0.0855 g) in EtOH-terButanol (1:1, 10 ml) were shaken in H 2 (50 psi) in a Parr hydrogenation apparatus for 16 h. The catalyst was filtered and washed with aqueous ethanol. The filtrate and washings were evaporated to dryness in a vacuo and the residue washed with acetone to obtain the acetone insoluble product PtdIns(3,4,5)P 3 -dihexadecanoyl, (+)-12) as a white powder (0.025 mg, 92%), [α] D +5.8° (c 0.2, CHCl 3 —MeOH—H 2 O, 2:1:0.1).
Partial Synthesis of PtdIns(3,4,5)P 3 from PtdIns(4,5)P 2
The two step reaction between PtdIns(4,5)P 2 and dibenzyl chlorophosphate was carried out as one-pot operation as follows. PtdIns(4,5)P 2 24, (in solution in chloroform-methanol-water (2:1:0.1) was treated with an excess of NEt 3 and the solvents removed by rotary evaporation under reduced pressure. The resulting triethylammonium salt was dried in a vacuo over KOH pellets. The dried salt was dissolved a mixture of anhydrous methanol and toluene, mixed with dibutyltin oxide (1 mol. equiv.) and heated at 50° C. for 2 hr. The solvents methanol and toluene were evaporated in a vacuum. The methanol-free residue was suspended in anhydrous THF+DMF (1:1) containing anhydrous NEt 3 (excess), cooled to −23° C. and stirred under insert gas and a solution of dibenzyl chlorophosphate (excess) in carbon tetrachloride was added dropwise. The reaction was stirred at −23° C. for 5 hr., allowed to warm to 5° C. and treated with and allowed to stand with ice-cold water overnight. The volatiles were removed under reduced pressure, the residue dissolved in chloroform-methanol-0.5 aqueous HCL and the proportions adjusted to 2:2:1.5 to obtain the lipids in the chloroform layer. Analysis of the chloroform layer by TLC using several protocols indicated the presence of products PtdIns(3,45)P 3 .
REFERENCE AND NOTES
1. (a). Whitman, M.; Downes, C. P.; Keeler, M.; Keller, T.; Cantley L. Nature 1988, 332, 644-646. (b). Traynor-Kaplan, A. E.; Harris, A. L.; Thompson, B. L.; Taylor, P.; Sklar, L. A. Nature 1988, 334, 353-356.
2. Reviewed in: Carpenter, C. L.; Cantley, L. C. Current Opinion in Cell Biology 1996, 8, 153-158.
3. Toker, A.; Meyer, M.; Reddy, K.; Falck, J. R.; Aneja, R.; Aneja, S.; Parra, A.; Burns, D. J.; Cantley, L. C. J. Biol. Chem. 1994, 269, 32358-32367.
4. Reviewed in: Duckworth, B. C.; Cantley, L. C. Lipid Second Messengers-Handbook of Lipid Research; Plenum Press: New York. 1996, 8 pp. 125-175.
5. Synthesis of PtdIns-3-phosphates: (a) Reference 3; (b) Gou, D. M.; Chen, C. S. J. Chem. Soc. Chem. Commun. 1994, 2125-2126; (c) Reddy, K. K.; Saady, M.; Falck, J. R.; Whited, G. J. J. Org. Chem. 1995, 3385-3390; (d) Bruzik, K. S.; Kubiak, R. J. Tetrahedron Lett. 1995, 36, 2415-2418; (e) Watanabe, Y.; Tomioka, M.; Ozaki, S. Tetrahedron 1995, 51, 8689-8976.
6. Freeman, I. P.; Morton, I. D., J. Chem. Soc. 1966, 1710-1714. Serdarevich, B. J. Amer. Oil. Chemists' Soc. 1967, 44, 381-385.
7. The fattyacyl composition of the cellular PtdIns-3-phosphates is presumed to be identical with cellular PtdIns(4,5)P 2 ; reference 1a.
8. Aneja, R.; Aneja, S. G.; Parra, A. Tetrahedron Asymmetry 1995 (No. 1), 17-18.
9. Shashidhar, M. S.; Keana, F. W.; Volwerk, J. J.; Griffith O. H. Chem. Phys. Lipids, 1990, 53, 103-113.
10. Gigg, J.; Gigg, R.; Payne, S.; Conant, R. J. Chem. Soc. Perkin Trans. I 1987, 1757-1762.
11. Aneja, R.; Aneja, S.; Pathak, V. P.; Ivanova, P. T. Tetrahedron Lett. 1994, 35, 6061-6062.
12. Gou, D. M.; Liu, Y. K.; Chen. S. C. Carbohydr. Res. 1992, 234, 51-64.
13. Chouinard, P. M.; Bartlett, P. A. J. Org. Chem. 1986, 51, 75-78.
14. Aneja R. Biochem. Soc. Trans. 1974, 2, 38-41.
15. Aneja, R.; Chadha, J. S.; Davies, A. P. Biochim. Biophys. Acta, 1970, 218, 102-111. Aneja, R.; Davies, A. P. Chem. Phys. Lipids 1970, 4, 60-71.
16. Freeman, I. P.; Morton, I. D., J. Chem. Soc. 1966, 1710-1714. Serdarevich, B. J. Amer. Oil Chemists' Soc. 1967, 44, 381-385.
17. Aneja, R.; Ivanova, P. T. Unpublished. | Disclosed are unique starting materials, reaction sequences and intermediate compounds for the preparation of D-3-phosphorylated phosphoinositides (3-PPI) of unambiguous structure and absolute stereochemistry. The enantiomerically pure D-3-phosphorylated phosphoinositides also provided have many uses, including the development of diagnostics and therapeutics based on the roles of 3-PPI in intracellular signaling. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
This is a continuation application of U.S. patent application Ser. No. 08/587,087 filed Jan. 16, 1996, which is a continuation-in-part application of U.S. patent application Ser. No. 08/549,995, filed Oct. 27, 1995, now U.S. Pat. No. 5,647,724.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a substrate processing apparatus and, more particularly, to a substrate transport with substrate holders each capable of transporting more than one substrate at the same time.
2. Prior Art
Mattson Technology has a system known as its ASPEN system that moves two semi-conductor wafers into and out of a process chamber at the same time. Batch systems, single wafer systems and cluster tool systems are also known in the prior art. U.S. Pat. No. 4,951,601 discloses a substrate processing apparatus with multiple processing chambers and a substrate transport apparatus. U.S. Pat. No. 5,180,276 discloses a substrate transport apparatus with two substrate holders. U.S. Pat. No. 5,270,600 discloses a coaxial drive shaft assembly of a substrate transport apparatus. U.S. Pat. No. 4,094,722 discloses a rotatable palette that holds four wafers. U.S. Pat. No. 4,381,965 discloses a multi-planar electrode plasma etcher. U.S. Pat. No. 4,675,096 discloses a take-in-and-out chamber with side-by-side take-in and take-out positions. Other related art include the following:
U.S. Pat. No. 1,190,215 U.S. Pat. No. 2,282,608
U.S. Pat. No. 3,730,595 U.S. Pat. No. 3,768,714
U.S. Pat. No. 3,823,836 U.S. Pat. No. 3,874,525
U.S. Pat. No. 4,062,463 U.S. Pat. No. 4,109,170
U.S. Pat. No. 4,208,159 U.S. Pat. No. 4,666,366
U.S. Pat. No. 4,721,971 U.S. Pat. No. 4,730,975
U.S. Pat. No. 4,907,467 U.S. Pat. No. 4,909,701
U.S. Pat. No. 5,151,008 U.S. Pat. No. 5,333,986
U.S. Pat. No. 5,447,409
EPO Publication No.: 0423608
Japanese Publication No.: 2-292153
SUMMARY OF THE INVENTION
In accordance with one embodiment of the present invention, a substrate transport apparatus is provided comprising a movable arm assembly and two substrate holders. The movable arm assembly has two pairs of driven arms. The two substrate holders include a first holder which is suitably sized and shaped to simultaneously hold at least two spaced substrates thereon. Each substrate holder is individually connected to a separate one of the pairs of driven arms.
In accordance with another embodiment of the present invention, a substrate processing apparatus is provided comprising a supply of substrates, a substrate transport module, and a substrate processing module. The substrate transport module is connected to the supply of substrates and includes a movable arm assembly and two substrate holders mounted to the movable arm assembly for extension and retraction relative to a center of the movable arm assembly. A first one of the holders has two separate holding areas for simultaneously holding two substrates. The substrate processing module is connected to the substrate transport module and is suitably sized and shaped to simultaneously receive two substrates transported into the processing module by the movable arm assembly and the first holder. The substrate transport module can move more than two substrates without rotating the substrate holders about a center axis of the transport module.
In accordance with another embodiment of the present invention, a substrate transport apparatus is provided comprising a movable arm assembly and two substrate holders. The movable arm assembly has two drive arms and two pairs of driven arms. Each pair of driven arms has a first driven arm connected to a first one of the drive arms and a second driven arm connected to a second one of the drive arms. The two pairs of driven arms are generally located on opposite sides of the drive arms. The two substrate holders are individually connected to separate ones of the pairs of driven arms. The two substrate holders each have more than one separate substrate holding area for each of the holders to simultaneously hold more than one substrate at the same time.
In accordance with another embodiment of the present invention, a substrate holder for use with a substrate transport apparatus is provided comprising a frame member and a mount. The frame member has a general flat planar shape with two spaced apart recesses into a front end of the frame member. The mount is connected to the frame member for attaching the frame member to the transport apparatus.
DETAILED DESCRIPTION OF THE DRAWINGS
The foregoing aspects and other features of the invention are explained in the following description, taken in connection with the accompanying drawings, wherein:
FIG. 1 is a schematic top plan view of a substrate processing apparatus having a substrate transport apparatus incorporating features of the present invention;
FIG. 2 is a top plan view of an X-shaped section of a movable arm assembly of the substrate transport apparatus shown in FIG. 1;
FIG. 3 is an end view of the X-shaped section shown in FIG. 2 with a partial cut away section;
FIGS. 4A-4E are schematic top plan views of the substrate transport apparatus shown in FIG. 1 showing the movable arm assembly and the substrate holders at five different positions;
FIG. 5 is an end view with partial cut away sections of an alternate embodiment of the present invention;
FIG. 6 is a top plan view of an alternate embodiment of a substrate holder;
FIG. 7 is a schematic top plan view of a substrate processing apparatus using two of the holders shown in FIG. 6;
FIG. 8 is an enlarged top plan view of the transport apparatus shown in FIG. 7 having four substrates thereon;
FIG. 9A is a schematic top plan view of the transparent apparatus shown in FIG. 8 at a first extended position;
FIG. 9B is a schematic top plan view as in FIG. 9A showing the transport apparatus at a second extended position;
FIG. 10 is a schematic top plan view of an alternate embodiment of a transport apparatus having two different types of substrate holders; and
FIG. 11 is a perspective view of another alternate embodiment of a substrate holder.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, there is shown a schematic top plan view of a substrate processing apparatus 10 having a substrate transport apparatus 12 incorporating features of the present invention. Although the present invention will be described with reference to the embodiments shown in the drawings, it should be understood that the present invention may be embodied in many forms of alternative embodiments. In addition, any suitable size, shape or type of materials or elements could be used.
In addition to the substrate transport apparatus 12, the substrate processing apparatus 10 includes multiple substrate processing chambers 14 and substrates cassette elevators 16 connected to a chamber 15. The transport apparatus 12 is located, at least partially, in the chamber and is adapted to transport planar substrates, such as semiconductor wafers or flat panel displays, between and/or among the chambers 14 and elevators 16. In alternate embodiments, the transport apparatus 12 could be used in any suitable type of substrate processing apparatus.
Referring also to FIGS. 2, 3 and 4E, the transport apparatus 12 generally comprises a movable arm assembly 18, a coaxial drive shaft assembly 20, and two substrate holders 22, 23. The coaxial drive shaft assembly 20 includes a first shaft 24 rotatably located inside a second shaft 26. The two shafts 24, 26 are axially rotatable in unison with each other in same directions and in opposite directions relative to each other and, are movable up and down with each other as indicated by arrow Z. One such coaxial drive shaft assembly is disclosed in U.S. Pat. No. 5,270,600 which is hereby incorporated by reference in its entirety. However, any suitable type of drive assembly could be used including a non-coaxial drive assembly or a coaxial drive assembly with more than two drive shafts.
The movable arm assembly 18 comprises a general X-shaped section 28 and four distal arms 30, 31, 32, 33. The distal arms 30, 31, 32, 33 connect the substrate holders 22, 23 to the X-shaped section 28. The X-shaped section 28 has three arm members 34, 35, 36 that form four proximal arm section 38, 39, 40, 41 of the two crossed arms 42, 43. The section 28 is referred to as being X-shaped. However, the two arms 42, 43 are movable relative to each other at their center connection to the drive shaft assembly 20. Thus, the X-shaped section 28 is a movable or reconfigurable X-shape. In one position, shown in FIGS. 1 and 4C, the X-shaped section looses its general X-shape because the two arms 42, 43 are directly aligned with each other. However, in all other non-aligned positions the section 28 has a general X-shaped profile. Thus, the section 28 is referred to herein as an X-shaped section for lack of a better descriptive term. The two crossed arms 42, 43 form the general X-shape. The first arm 42 comprises the first arm member 34 which forms the first and third arm sections 38, 40. The second arm 43 comprises the second and third arm members 35, 36 which form the second and fourth arm sections 39, 41.
As seen best in FIG. 3, the first arm member 34 is fixedly attached to the first drive shaft 24 by screw 44. The first arm section 38 has a pivot 46 at its distal end and is connected to the shaft assembly 20 at a first height. A stop 48 extends below the first arm section 38. The third arm section 40 is integral with the first arm section 38. The third arm section 40 has an aperture 50 that allows the drive shaft assembly 20 to pass therethrough. The third arm section 40 extends from the drive shaft assembly 20 at a third height on the assembly 20. Located at a distal end of the third arm section 40 is an upward extension 51 with an upper overhang section 52 having a pivot 54. The overhang section 52 extends inward towards the center of the X-shape. The second arm section 39 has an aperture 58 that allows the drive shaft assembly 20 to pass therethrough. The second arm section 39 is fixedly attached to the second drive shaft 26 by a screw 56. The second arm section 39 extends from the drive shaft assembly 20 at a second height on the assembly 20. Located at the distal end of the second arm section 39 is a pivot 60 on an upstanding post 62. The fourth arm section 41 has an aperture 64 that allows the drive shaft assembly 20 to pass therethrough. The fourth arm section 41 is fixedly attached to the second drive shaft 26 by a screw 66. The distal end of the fourth arm section 41 has an upward extension 69 with an upper overhang section 68 having a pivot 70. The fourth arm section 41 extends from the drive shaft assembly at a fourth height on the assembly 20.
Thus, the four arm sections 38, 39, 40, 41 extend from the drive shaft assembly 20 at four different heights on the assembly 20. The third arm section 40 and the fourth arm section 41 form channels 72, 74 to allow the distal ends of the first and second arm sections 38, 39 to pass through.
As seen best in FIG. 4E, the first distal arm 30 has one end pivotably mounted on the first pivot 46 of the first arm section 38 and an opposite end pivotably mounted to the first substrate holder 22. The second distal arm 31 has one end pivotably mounted on the second pivot 60 of the second arm section 39 and an opposite end pivotably mounted to the first substrate holder 22. Thus, the first holder 22 is pivotably mounted to the pair of pivots 46, 60; one pivot from each of the crossed arms 42, 43 of the X-shaped section 28. The third distal arm 32 has one end pivotably mounted on the third pivot 54 of the third arm section 40 and an opposite end pivotably mounted to the second substrate holder 23. The fourth distal arm 33 has one end pivotably mounted on the fourth pivot 70 of the fourth arm section 41 and an opposite end pivotably mounted to the second substrate holder 23. Thus, the second holder 23 is pivotably mounted to the pair of pivots 54, 70; one pivot from each of the crossed arms 42, 43 of the X-shaped section 28. In alternate embodiments other types of connections of the distal arms to the X-shaped section 28 and/or the holders 22, 23 could be provided. Connectors or a connecting assembly different than the distal arms 30, 31, 32, 33 could also be provided.
The first pair of pivots 46, 60 and their corresponding distal arms 30, 31 are located in a first relative lower plane of movement. The first substrate holder 22 is also located in this first relative lower plane. The second pair of pivots 54, 70 and their corresponding distal arms 32, 33 are located in a second relative upper plane of movement. The second substrate holder 23 is also located in this second relative upper plane. In a preferred embodiment the first pair of distal arms 30, 31 has intermeshed gear sections at holder 22 for registry of movement to keep the holder 22 in a constant orientation. The second pair of distal arms 32, 33 also preferably has intermeshed gear sections at holder 23 for registry of movement to keep the holder 23 in a constant orientation. However, any suitable type of system to keep the holders 22, 23 properly orientated could be used.
The substrate holders 22, 23 are adapted to be inserted and removed from the chambers 14 and elevators. 16. The holders 22, 23 are adapted to hold substrates thereon and thereby allow the substrates to be moved between and/or among the chambers 14 and elevators 16. Suitable means are provided (not shown) for keeping the substrate holders aligned with the movable arm assembly 18 such that the holders 22, 23 are always pointed in an outward direction for proper straight insertion into a chamber or elevator. This can include the ends of the distal arms 30, 31, 32, 33 at the holders 22, 23 having intermeshed gear teeth or an S-band joint constraint, such as described in U.S. patent application Ser. No. 08/421,533 entitled "Articulated Arm Transfer Device", which is hereby incorporated by reference in its entirely. In alternate embodiments any suitable type of substrate holders or orientation constraint could be used.
Referring now to FIGS. 4A-4E, the operation of the substrate movement apparatus 12 will be described. FIG. 4C and FIG. 1 show the apparatus 12 at a home position. In this home position both drive shafts 24, 26 can be rotated in the same direction to rotate the holders 22, 23 in front of a selected one of the chambers 14 or elevators 16. In this home position, the upper holder 23 is located above the lower holder 22. Distal arm 33 is located over distal arm 30. Distal arm 32 is located over distal arm 31. First arm section 38 is located over the fourth arm section 41 except for overhang section 68. Second arm section 39 is located over the third arm section 40 except for overhang section 52.
FIG. 4A shows the upper holder 23 in an extended position with the lower holder 22 in a retracted position. FIG. 4B shows an intermediate position of the apparatus 12 between the home position shown in FIG. 4C and the upper holder extended position shown in FIG. 4A. In order to move between these two positions, the two drive shafts 24, 26 are axially rotated in reverse directions relative to each other. FIG. 4E shows the lower holder 22 in an extended position with the upper holder 23 in a retracted position. FIG. 4D shows an intermediate position of the apparatus 12 between the home position shown in FIG. 4C and the lower holder extended position shown in FIG. 4E. The two holders 30 22, 23 are moved in opposite unison between their extended positions and their home positions with the upper holder 23 moving in a plane above the lower holder 22. The movable arm assembly 18 allows sufficient room for the holder being retracted to move closer to the center of the X-shaped section. The stop 48 limits axial rotation of the two crossed arms 42, 43 relative to each other. The movable arm assembly 18 is designed to allow each arm 42, 43 to rotate about 160°. However, in alternate embodiments other degrees of rotation could be provided. The X-shaped section 28 has been designed to allow unobstructed movement of the arm sections 38, 39, 40, 41 between the positions shown in FIGS. 4A and 4E and unobstructed movement of the distal arms and holders in their two different relative planes of motion. This allows the two holders 22, 23 to be positioned on the same side of the assembly 18. The two pairs of distal arms 30, 31 and 32, 33 function as forearm sections for their respective substrate holders 22, 23. In alternate embodiments more than two substrate holders could be provided and/or, could be located on additional sides of the assembly 12. The drive shaft assembly 20 vertically moves the holders 22, 23 in direction Z (see FIG. 3) to align the holder to be extended with the opening of the intended receiving chamber 14 or elevator 16. Positioning the two holders 22, 23 on the same side of the assembly can speed-up throughput in the substrate processing apparatus 10. Positioning of the holders 22, 23 on the same side of the apparatus 12 is accomplished by allowing the holders to move along substantially parallel paths, one holder above the other, with one moving in a plane over the other.
Referring now to FIG. 5, there is shown an alternate embodiment of the present invention. The transport apparatus 112 has a coaxial drive shaft assembly 120 with two drive shafts 124, 126. The movable arm assembly 118 has four drive arms 138, 139, 140, 141 and four driven arms or forearms 130, 131, 132, 133. Two holders 122, 123 are attached to ends of the forearms 130, 131, 132, 133. In this embodiment, the second and fourth drive arms 139 and 141 are fixedly connected to each other by fasteners 156 (only one of which is shown) The fourth drive arm 141 is fixedly attached to the top of the outer drive shaft 126 by fasteners 166 (only one of which is shown). Thus, when the outer drive shaft 126 is moved, the second and fourth drive arms 139, 141 are moved. The third drive arm 140 has a section 140a that fasteners 140b are attached to. The fasteners 140b are also attached to section 138a of the first drive arm 138. This fixedly attaches the first drive arm 138 to the third drive arm 140. The fourth drive arm 141 has a pocket 180 to allow the section 140a to move therethrough. The first drive arm 138 is fixedly attached to the top of the inner drive shaft 124 by fasteners 144 (only two of which are shown). The third drive arm 140 has an extension 151 attached to it that has the pivot 154 thereon. Likewise, the fourth drive arm 141 has an extension 169 attached to it that has the pivot 170. The first and second drive arms 138, 139 also have pivots 146, 160, respectively. The four forearms 130, 131, 132, 133 are mounted on the pivots 146, 154, 160, 170 with suitable bearings. This embodiment is more compact than the embodiment shown in FIG. 3 and is easier to manufacture. There is also virtually no chance that the drive arms will move relative to their respective drive shafts.
In another alternate embodiment, two drive shaft assemblies could be used; one extending upward into the chamber 15 and one downward into the chamber 15. Referring to FIG. 1, because the driven arms can extend and retract in a single radial direction on one side of the drive shaft, the substrate holders can withdraw a substrate from one of the chambers 14 or elevator 16 and insert a substrate into the same chamber 14 or elevator 16 without rotating the substrate holders about the center axis of the drive shaft assembly. This can obviously save time in transporting substrates. The ability to have the driven arms and substrate holders on the same side of the drive shaft assembly is an important feature and improvement for the present invention.
Referring now to FIG. 6, an alternate embodiment of a substrate holder 200 is shown. The holder 200 generally comprises a frame 202 and a mount 204. The frame 202 has a general flat planar shape with two spaced apart recesses 206, 208 into a front end 210 of the frame 202. The frame 202 also has a third recess 212 in its front end 210 between the first and second recesses 206, 208. The front end 210, thus, has four forwardly extending arms 214, 216, 218, 220. Mounted to the frame 202 are six point contacts 222. The point contacts 222 are preferably comprised of quartz or diamond and extend above the top surface of the frame 202. Three point contacts 222 are provided at each of the first and second recesses 206, 208. Each arms 214, 216, 218, 200 has one of the point contacts 222 proximate its end. A point contact 222 is also located at the rear ends of each of the first and second recesses 206, 208. Substrates placed on the holder 200 rest on the point contacts 222; not directly on the frame 202. However, in alternate embodiments any suitable type of system can be used to locate or mount substrates to the holder 200. The frame and point contacts, in the embodiment shown, are suitably configured to hold up to two substrates at the same time; one above the first recess 206 and another above the second recess 208. The holder 200 is adapted to hold the two substrates in a same plane above and parallel to the frame 202 and in a side-by-side configuration. In alternate embodiments, the frame 202 could have other shapes dependent upon how many substrates it can carry and the shape of the processor and elevator modules it is intended to be inserted into. The mount 204 is fixedly connected to the rear end 224 of the frame 202. In an alternate embodiment the mount could be an integral part of the frame rather than a member attached to the frame. The mount 204 has two driven arms 226, 228 pivotably connected to it. Preferably, suitable means (not shown) are provided at the mount 204 for constraining the driven arms 226, 228 such that they move in registration with each other, such as intermeshing gear teeth or a dual S-band constraint.
Referring also to FIG. 7, there is shown a substrate processing apparatus 230 having a substrate transport apparatus 232 with two of the substrate holders 200. The processing apparatus 230 is similar to the apparatus 10 shown in FIG. 1, but has two dual substrate cassette elevators 234, 235, four dual substrate processing chambers 236, a dual aligner 238, a dual incooler 240, and two dual substrate transports 242, 243. The first transport 242 transports two subsubstrates at a time from the first elevator 234 to the aligner 238. The second transport 243 transports two substrates at a time from the incooler 240 to the cassettes in the second elevator 235.
Referring also to FIG. 8, the substrate transport apparatus 232 is shown holding four substrates S. The transport apparatus 232, in the embodiment shown, includes a drive 244 and a movable arm assembly with two drive arms 246, 247 and four driven arms 248, 249, 250, 251. Preferably, the drive is a coaxial drive shaft assembly such as described in U.S. patent application Ser. No. 08/434,012 which is hereby incorporated by reference in its entirety. However, any suitable type of drive could be used. A similar drive arm assembly is described in U.S. Pat. No. 5,180,276 which is hereby incorporated by reference in its entirety. In the embodiment shown in FIG. 8, mounted to the ends of the two sets of driven arms 248, 249 and 250, 251 are the two substrate holders 200a and 200b. FIGS. 7 and 8 shows the transport apparatus 232 at a home position. Referring to FIGS. 9A and 9B the transport apparatus is shown at two different extended positions. In the first extended position shown in FIG. 9A, the first holder 200a is moved into the aligner 238 to remove the two substrates S 1 and S 2 . In the second extended position shown in FIG. 9B the first holder 200a has been retracted out of the aligner 238 and the second holder 200b has been inserted into the processing chamber 236 to deliver the two substrates S 3 and S 4 . This illustrates that the transport apparatus 232 and holders 200 can move more than two substrates without rotating the holders 200 about a center axis of the transport apparatus.
From the foregoing description it should be evident that the holder 200 allows for twice the substrate throughput as a single substrate holder. However, the expected increase in size of the footprint of the substrate processing apparatus is only about 40%. In addition, the increase in cost for manufacturing this type of substrate processing apparatus is expected to be only about 30% more than an apparatus with single substrate holders. Thus, throughput can be increased 100% with an increase in footprint of only 40% and increase in cost of only 30%. In addition, the dual substrate holder 200 in combination with the same side transport apparatus 12 can further increase throughput more than 100% due to the fact that the movable arm assembly 18 does not need to be rotated to remove substrates from a chamber and insert new substrates into the chamber.
Referring now to FIG. 10, there is shown an alternate embodiment of the present invention. In this embodiment the transport apparatus 232 includes two different substrate holders 200 and 201. The second substrate holder 201 is for carrying a single substrate. Referring to FIG. 11, there is shown a perspective view of another embodiment of a substrate holder 260 for carrying two substrates. However, in this embodiment, the frame 262 is suitably configured to hold the substrates in a vertically offset parallel or stacked configuration; one on bottom frame section 264 and one on top frame section 266. However, any suitable frame configuration could be used.
It should be understood that the foregoing description is only illustrative of the invention. Various alternatives and modifications can be devised by those skilled in the art without departing from the spirit of the invention. Accordingly, the present invention is intended to embrace all such alternatives, modifications and variances which fall within the scope of the appended claims. | A substrate processing apparatus having a supply of substrates, a substrate transport module, and a substrate processing module. The transport module has a movable arm assembly and two substrate holders mounted to the movable arm assembly. The substrate holders each have two separate holding areas for simultaneously holding two substrates. The movable arm assembly has two pairs of driven arms. Each pair of driven arms is connected to a separate one of the holders for extending and retracting the holders along a radial path relative to a center of the movable arm assembly. | 8 |
BACKGROUND OF THE INVENTION
[0001] The high storage density of current data carriers entails a considerable risk of data misuse in the private, economic and military domains. Therefore, the task has arisen of completely destroying data before it falls into the hands of unauthorized individuals. Owing to the worldwide dissemination of compact disks (CD-ROM or CD read-only memory) and the increasing dissemination of digital versatile disks (DVDs), this task has become a technical challenge, especially since the objective of the creators of that generation of data carriers was to ensure the inviolability of the stored data.
[0002] Various attempts at destroying CD-ROMs and DVDs quickly and safely have failed, in particular because data structures which have not been completely destroyed can be made legible again by current means of reconstructing data using optical devices and algorithms originating from data encryption technology. The highest data destruction rate with the least technical expenditure has been achieved in the laboratory by thermally destroying the data by means of thin pyrotechnic layers in the form of films. However, their physical association with the data carriers gave rise to unexpected difficulties, in particular with respect to their adhesiveness, layer thickness, reaction rate on combustion and their irregular and often non-reproducible combustion behavior.
[0003] GE-A-2 282 136 discloses inter alia a pyrotechnic film in which a quickly oxidizing material is applied to both sides of a structured layer acting as an oxidant. Following ignition, the two layers bring about a strongly exothermic process with a high reaction rate and generate a combustion temperature of several thousand degrees Celsius.
[0004] Practical experiments have shown that a film of this type, which was developed for the ignition of gas generators and rocket engines, burns away too quickly and too greatly affects or even destroys the environment of the data carriers. For safety reasons alone, its use with CD-ROMs, DVDs and CD-RWs (CD rewriter drives) is out of the question.
[0005] Therefore, the object of the present invention is to produce a pyrotechnic layer for the destruction of data on carriers, in particular read-only memory disks, which does not have the aforementioned disadvantages, ensures complete destruction of all data and requires a layer thickness of less than 1.0 mm. The layer must adhere mechanically and properly to conventional carriers and must also resist any thermal expansion and/or flexion and must not flake off in practical use. Furthermore, the pyrotechnic layer must not include any toxic substances and/or produce them either alone, or in combination or reaction with housing parts or data carriers themselves.
BRIEF DESCRIPTION OF THE INVENTION
[0006] In accordance with the foregoing and other objects and purposes, a pyrotechnic layer of the present invention is arranged on or in a flat substrate in the operating region of the data carrier, and comprises a pyrotechnic material incorporated into an inert substrate. The substrate may be an inert metal, the pyrotechnic material being introduced into a series or network of pores therein. Alternatively, the inert material may take the form of a non-metallic, non-woven fabric or other structure, such as a mesh, burled, or honeycomb structure, capable of receiving the pyrotechnic material. The pyrotechnic material may comprise a thermite mixture.
[0007] The term “inert material” or “inert metal” used herein are taken to mean that the material makes no or only a relatively small contribution to the temperature increase during the combustion of the pyrotechnic layer and is therefore not primarily reactive, in contrast to the structured material according to GB-A-2 282 136. Such inert materials may include both metal and non-metal substrate materials.
[0008] High mechanical strength is obtained by means of the inert carrier structure. In addition, a targeted evolution and propagation of heat is achieved, in which the inert structure forms a type of thermal buffer and prevents uncontrolled energy losses caused by diffusion.
[0009] The overall energy can be kept low by the structure of the invention. There is no risk of fire, and the devices to be used suffer no or little damage due to the resulting evolution of heat. System users are also not endangered by explosions, or the like.
[0010] The present invention can be used universally in connection with driver/reader devices and on data storage devices owing to its good adhesiveness and the small layer thickness required.
[0011] The incorporation of a range of inert material structures opens up a wide range of applications. Both the formation of very thin layers and improved adhesion, in particular to the polycarbonate of CD-ROMs, etc., and reduced sensitivity to vibration and shock can be achieved by differing constructions of the invention.
[0012] Use of a glass-fiber non-woven fabric is particularly suitable. It is commercially available as a finished product and has great flexibility. Non-woven fabrics comprising other materials such as fine rock wool or textiles, which can produce no or only a little reaction heat, can also be used. Relatively thin non-woven fabrics are sufficient, an optimum weight per unit area being in the region of 30 g/m 2 .
[0013] Thermite mixtures have proved successful and are advantageously not stoichiometric mixtures, as these react very vigorously. The inclusion of excess reducing agent can allow the reaction rate to be controlled. The inclusion of powdered iron may permit an optimum temperature gradient in the storage medium. The iron does not primarily participate in the main chemical reaction; it reduces the reaction temperature and releases the absorbed energy in the form of radiation in a time-delayed manner.
[0014] Use of an inert metal substrate in the form of an open pore foam as the inert carrier structure forms a three-dimensional lattice having excellent mechanical and adhesive properties. Such a metal substrate, like the non-woven fabric, mesh, burled and/or honeycomb structure, does not participate in the chemical reaction; it acts primarily as an energy store.
[0015] Surprisingly, a pyrotechnic mass introduced into the metal substrate adheres outstandingly well in the latter without any further surface treatments, etc. The metal substrate can also be glued without any problems to other materials, without the disadvantages which may exist with adhesion of the pyrotechnic mass.
[0016] A nickel or nickel alloy metal foam is commercially available with a porosity of 90% to 95%, making it capable of absorbing a large pyrotechnic mass. Such a metal foam has proved particularly successful because it is also chemically inert at the high temperatures produced during combustion and therefore no exothermic heat is generated.
[0017] A pyrotechnic layer in the range of 0.3 to 0.6 mm has been found to be a preferable thickness and, in the case of rotating data carriers, cause only controllable imbalances which can easily be compensated for by known means. The pyrotechnic layer may be exposed or covered by a protective layer or the like. A polymeric protective layer can be applied in the form of a protective lacquer. Protection against mechanical damage and/or untimely initiation can also be provided by other covering materials, such as metal foils or plastic films.
[0018] An incandescent igniter with connecting channels containing an igniting composition may be utilized to form an ignition chain to facilitate the targeted and rapid destruction of stored data and the data carrier itself in emergency situations. An integral power supply incorporating a miniature battery can increase system safety and facilitate the automated triggering of data destruction.
[0019] The pyrotechnic layer of the present invention may be formed by compounding the components of the pyrotechnic mass with an appropriate binder and subsequently adding an appropriate spreading agent, such as butyl acetate, to form a spreadable mass. The mass is then applied to the inert substrate and dried.
[0020] Although there is a wide variety of possible methods of applying the pyrotechnic mass, the screen printing process commonly known from printing technology is particularly advantageous because it permits precise positioning of the mass and thus produces little waste. It is also well suited to discontinuous batch operation during preparation of the mass.
[0021] The pyrotechnic layer of the invention may be applied in a simple manner either to the upper surface of a CD-ROM, to its caddy or as an intermediate layer in the case of a DVD readable on both sides. The pyrotechnic layer can be incorporated into the operating region of data carriers such as CD-ROM and DVD servers, jukeboxes, CD rewriters, MO, ZIP, JAZ, PC-card and PD drives. The layer can be incorporated in the same way into any other removable data carriers without difficulty.
[0022] The arrangement of one or more pyrotechnic layers in a multi-layer data carrier is also possible, but may require additional working steps, known to those skilled in the art, in the manufacturing process and adjustment and/or adaptation of the optical reading system to the modified layer thicknesses and the position of the data planes.
[0023] The pyrotechnic layer can also be directly incorporated into component parts of readers, these parts preferably being of a replaceable nature.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] Embodiments of the invention will be described in the following with reference to the annexed drawings, wherein:
[0025] [0025]FIG. 1 is a section view through a CD-ROM having an upper pyrotechnic layer in accordance with the invention;
[0026] [0026]FIGS. 2 a - 2 c are enlarged cross-sectional views of three variants of the pyrotechnic layer;
[0027] [0027]FIG. 2 d is an enlarged sectional view of a metallic foam which may be used for the inert structure of the invention;
[0028] [0028]FIG. 2 e is an enlarged sectional view of a pyrotechnic layer utilizing the metallic foam of FIG. 2 d;
[0029] [0029]FIG. 3 is a partial sectional view of a DVD with an intermediate pyrotechnic layer;
[0030] [0030]FIG. 4 is a partial section view of the DVD taken along line x-x of FIG. 3 depicting the intermediate layer with its aids for the parallel arrangement of the data carriers;
[0031] [0031]FIG. 5 is a top plan view of a caddy with a pyrotechnic layer having an integral voltage source and ignition device; and
[0032] [0032]FIG. 6 is a sectional view of a data cartridge illustrating the basic principle of the association of pyrotechnic layers with data carriers.
[0033] In all the figures, like functional parts are provided with like reference numerals.
DETAILED DESCRIPTION OF THE INVENTION
[0034] A pre-recorded/written CD-ROM is designated by 1 in FIG. 1. A pyrotechnic layer 4 is glued onto the data carrier portion 2 of this commonly known, commercially available CD-ROM 1 and extends radially inwardly as far as the inner (first) data track, terminating 5 mm from the bore 3 and, correspondingly, extending outwardly as far as the last data track, terminating 5 mm from the periphery of the disk. A conventional imprint 5 may be provided thereabove, either in the form of a printed label or applied by screen printing.
[0035] The CD-ROM thus coated can be initiated by known ignition means and, owing to the considerable resulting evolution of heat, loses all the data, i.e. all the bits become illegible without the polycarbonate of the data carrier igniting.
[0036] [0036]FIGS. 2 a to 2 c show simplified sectional views of variants of the pyrotechnic layer 4 according to the invention. In all cases, the layer thickness is 0.4 mm. They differ only in the type of inert substrate structure utilized. In FIG. 2 a , the inert substrate structure is a triple-layered non-woven fabric 40 comprising glass fibers; in FIG. 2 b , it is a tissue/mesh 41 , likewise comprising glass fibers, and in FIG. 2 c , it is a film 42 having a burled structure and regularly distributed holes 43 and comprising a mineral or metal material. Heat-resistant plastics can also be used.
[0037] [0037]FIGS. 3 and 4 depict a portion of a DVD 10 with a centrally arranged, compact pyrotechnic layer 4 ′. While the two data carriers 2 ′ are constructed and recorded in a conventional manner, the layer 4 ′ comprises an intermediate layer 6 formed as a spacer between them.
[0038] The intermediate layer 6 is formed with a substrate in the form of an interior toroidal core 7 having an outer, thickened ring portion having radial openings 6 c through which the pyrotechnic mass extends outwardly. A flat, disc-like central portion of the substrate core is provided with numerous holes 6 D through which the pyrotechnic mass extends and joins upper and lower portions thereof applied to the corresponding surfaces of the substrate. An inner ring portion 6 b of the substrate core forms an inner support for the intermediate layer 6 and a side wall for the pyrotechnic mass.
[0039] The pyrotechnic layer 4 ′ is in itself equivalent to that shown in FIG. 2 a , except that its pyrotechnic mass is further connected to the upper and lower surfaces of the substrate by means of the honeycomb structure formed by the holes 6 d in the substrate. Because the pyrotechnic mass extends outwardly through the radial holes 6 c , the DVD 10 can be ignited from the outside, which ignition can even be carried out during operation by the means described hereinbelow.
[0040] [0040]FIG. 5 shows the incorporation of a pyrotechnic layer 4 ″ into a conventional caddy 20 . The two side walls are designated here by 23 , the four ends by 22 and the reading slide by 24 . The pyrotechnic layer 4 ″ is applied upon the inner surface of the transparent cover 26 of the caddy 20 and arranged concentrically about the portion 21 of the cover overlying the bearing flange of the CD-ROM. The boundary lines of the layer 4 ″ can be seen in FIG. 5. A concentric recess is advantageously provided for the pyrotechnic layer on the inner surface of the cover 26 , the pyrotechnic layer being let into the recess and forming a plane with the inner surface of the cover.
[0041] [0041]FIG. 5 also shows an ignition element 8 comprising an incandescent igniter 8 a and three ignition channels 9 which ignite the layer 4 ″ by means of electrical initiation. The ignition channels lie on the inner surface of the cover 26 .
[0042] The incandescent igniter 8 a can be initiated via its connections characterized by + and − by a control command of a connected computer and via its own power source 25 . However, the independent power source 25 —one or more button cells connected in series— also permits different, for example, electromechanical triggering of the igniter. Instead of direct ignition of the incandescent igniter 8 a by means of the power source 25 , an induction coil could also be used to supply a pulsed current to the incandescent wire of the igniter.
[0043] Whereas the hitherto described embodiments relate to flat data carriers, namely disks, FIG. 6 relates to a tape-type carrier, namely DLT (digital linear tape) or DAT (digital audio tape), but can also be incorporated into any floppy disk drive in a similar manner and is thus not restricted to a particular data carrier.
[0044] In accordance with the sectional view shown in FIG. 6, the corresponding cartridge 30 is constructed in the usual manner. It has two opposing side walls 31 spaced apart by end walls 32 , and its data carrier media 2 ″ mounted therebetween is wound upon spools 33 . The pyrotechnic layer 4 ″ is applied to the inner surfaces of the side walls 31 , while the igniter element 8 may be affixed to an end wall 32 .
[0045] For spatial reasons, the pyrotechnic layer 4 ″ is very thin, only 0.25 mm thick. However, the thermal energy is easily sufficient to destroy the data on ignition because it acts on the data carrier 2 ″ from both sides.
[0046] The two layers 4 ″ are synchronously ignited via two symmetrical ignition channels 9 ′ connected to the ignition element 8 itself provided with an incandescent igniter 8 a.
[0047] A method of producing the pyrotechnic layer of the invention is carried out using conventional techniques: In a first method step, 30% by weight of Fe 2 O 3 , 16% by weight of MnO 2 , 13% by weight of Al, 21% by weight of Zr and 20% by weight of Fe are mixed together and 3% by weight of polymeric binders are then added to this mixture. In a second method step, butyl acetate is added until a spreadable mass is formed which, in a third method step, is applied to a mesh,burled, and/or honeycomb structure of inert material, spread smooth and dried.
[0048] A preferred embodiment of the method of producing a pyrotechnic layer with a thickness of 0.4 mm is as follows:
[0049] In a first method step, 30% by weight of Fe 2 O 3 , 16% by weight of MnO 2 , 13% by weight of Al, 21% by weight of Zr and 20% by weight of Fe are mixed together as dry substances in a mortar and 12% by weight of binder 14 comprising styrene copolymer and modified rosin is then additionally added to this mixture. In a second method step, 52% by weight of butyl acetate is added to produce a spreadable mass and, in a third step, this mass is applied to a non-woven fabric comprising glass fibers by means of a conventional spreader. The spreader is slowly moved over the non-woven fabric at a constant rate to ensure that the latter is completely saturated with the pyrotechnic mass. The layer thus formed is then dried at 70°C. for 3 h.
[0050] The components of the pyrotechnic mixture have the following average particle sizes:
[0051] zirconium<5 μm
[0052] aluminum<100 μm
[0053] iron dioxide<100 μm
[0054] manganese oxide<100 μm
[0055] iron<150 μm
[0056] The binder 14 used is commercially available (Proga AG, CH-2540 Grenchen). The spreader is of the Erichson type (DESAG GmbH KG, D-58675 Hemer). The non-woven fabric is a “two-dimensional” non-woven fabric with a weight per unit area of 27 g/m 2 (ASEOL no. 31-56 made by ASEOL AG, CH-3000 Bern). The weight data for the binder and the butyl acetate are based on the total mass of the dry substance of the mixture.
[0057] The pyrotechnic layer is gluable to most surfaces, in particular when the surfaces have been roughened, using commercially available spray adhesives (e.g. Miranit manufactured by Ed. Geistlich und Sohne AG, CH-8952 Schlieren).
[0058] It is additionally recommended to spray the glued layer with a thin coating of clear lacquer, for example zapon lacquer, in order to increase its abrasion resistance.
[0059] In all cases, it has been demonstrated by practical testing that safe ignition of the pyrotechnic layer is also ensured during operation, i.e. during the read-out of data, and that even then no reconstructible data structures remain after ignition.
[0060] A preferred embodiment of the invention utilizing an inert metal substrate is shown in further detail in FIGS. 2 d and 2 e.
[0061] [0061]FIG. 2 d shows a section through a nickel foam after having been rolled to a desired layer thickness of 0.5 mm. Its sponge-like structure is designated by 44 with side edge surfaces 45 . The metal foam is commercially available as a flat material in the form of strips with a thickness of 1.5 mm (International Nickel GmbH, D-40211 Dusseldorf). It is brought to the desired thickness in the present case 0.5 mm, by calendaring (rolling) and then being cut to the desired external form.
[0062] The pyrotechnic mass is produced in the same way as for the glass-fibre non-woven fabric, although in this case the higher thermal capacity of the metal foam in relation to a glass-fibre non-woven fabric is taken into account, as follows:
[0063] In a first step, 34.4% by weight of Fe 2 O 3 , 18.6% by weight of MnO 2 , 14.9% by weight of Al and 25.1% by weight of Zr are mixed together and 7% by weight of polymeric binders are then added to this mixture. In a second step, butyl acetate is added until a spreadable mass is formed.
[0064] This mass is then introduced into the metal foam of FIG. 2 d by a known screen printing process and dried; see FIG. 2 e which shows an enlarged plan view of one end of the pyrotechnic layer ready for use.
[0065] It can also be seen from FIG. 2 e that the edge surfaces 45 of the actual structure 44 of the metal foam form a junction and thus the defined adhesion surface with the base (CD-ROM, DVD or caddy) to which the pyrotechnic layer is applied. A conventional contact adhesive which is sprayed on has again proved successful to adhere the pyrotechnic layer to the base surface.
[0066] If this pyrotechnic layer is used in connection with DVDs of high storage capacity (>8.5 Gbyte), it is recommended that the layer be placed between the levels (written reflectors), which produces an increase in the thickness of the DVD of at most 0.5 mm with an otherwise identical structure.
[0067] Owing to the flat surface of the pyrotechnic layer of the invention and the possibility of being able to introduce the pyrotechnic mass by screen printing precisely at a thickness of only tenths of a millimeter into the metal foam, also provided with flow holes, as exemplified in FIGS. 3 and 4, a sandwich-type structure as depicted therein, can also be precisely produced without causing relatively great imbalances in the rotating disk. Naturally, the focussing of the reader and/or recorder must be adapted to the positions of the data levels which may differ from standard.
[0068] A pyrotechnic layer of the sandwich type may be initiated via an ignition chain with a conventional incandescent igniter (electric primer capsule T7 manufactured by Comet GmbH, D-27574 Bremerhaven). The igniter acts on a combustible composition which is introduced into channels and is directed towards the exposed ends of the pyrotechnic layer.
[0069] The combustible composition is known per se and may comprise 66% zirconium FA and 34% manganese dioxide.
[0070] In order to ensure safe ignition in DVDs and the like having a high rotational speed, the size and positioning of channels for the combustible composition must be kept very small and precise to avoid deflection of the ignition stream to outer boundary layers.
[0071] The pyrotechnic layer described hereinabove can be incorporated into numerous other data carriers and similar structures and can easily be adapted to the specific requirements of the desired data destruction. Depending on the field of application and the quantity, other methods of introducing the pyrotechnic mass into the metal foam are also possible, for example coatings on a turntable, vacuum filling processes, etc.
[0072] The subject of the invention is not limited to electro-optical data storage systems. It can be applied just as well to magnetic, magneto-optical and also electronic storage. The small layer thickness required and the optimum distribution of heat within the ignited layer allow successful integration into most removable disk systems, irrespective of whether they function on an electronic, magnetic, magneto-optical or purely optical basis and without substantial structural changes being necessary.
[0073] The invention can also easily be combined with external and internal electromechanical and/or electronic and/or software security measures, for example so that any unauthorized attempt to access the stored data and/or the unauthorized removal of the data carrier initiates its destruction. | A data carrier, such as a memory disk, is provided with a pyrotechnic layer which can be ignited to destroy the data on the carrier. The pyrotechnic layer has an inert lining and can be triggered by a conventional electrical ignitor. The layer is based on a thermite mixture having an excess reducing agent. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates primarily to portable enclosures and particularly to portable enclosures used for shower and dressing areas in recreational settings.
2. Description of Prior Art
Portable enclosures and similar tent-like structures have long been known, including cases where the structures are used primarily for shower and dressing purposes. Most of the known structures were designed prior to the advent of the recreational vehicle and camping activity now popular with the general public. Therefore, most of the prior structures while being technically portable and consisting of various pole and canvas arrangements were awkward to erect and somewhat bulky to store once they were dismantled. Many of the structures were designed to be semi-permanent structures to be erected upon, for instance a beach where the structure would be removed at the end of a summer season and were not designed to be erected and dismantled on a daily basis.
A limiting feature of many of the former structures resided in the fact that many of the support members were required to be driven into the ground so the structure would be stable from exterior forces such as the wind. Some prior art structures required guy wires and stakes to ensure stability. These features had some distinct disadvantages. First, the structure would necessarily require a rather level surface on which to be erected, since a sloping grade would cause the support structure to lean and become unstable corresponding to the grade of the terrain. Secondly, since some of the supporting members would need to be driven into the ground, it became necessary to locate the structure or enclosure in an area where the ground was relatively soft and would preclude erection in rocky areas or in areas consisting of a concrete or asphalt base such as might be found in park areas in certain cases. Finally, the act of driving stakes, posts, or stringing guy wires is time-consuming and difficult for many individuals attempting to erect such an enclosure.
Additionally, a review of the portable tent-like structures in the prior art will show that many of the structures were complex in design and time consuming to erect reflecting to some extent the intention that many of these structures, once erected, would not be dismantled on a daily basis. On the contrary, present day recreational vehicle and camping markets comprise a highly transient population which frequently moves from place to place on a daily basis and requires that the portable enclosures be erected, dismantled and stored in a matter of minutes.
SUMMARY OF THE INVENTION
Therefore, it is an object of the present invention to provide a portable enclosure for recreational use which is free standing and does not require stakes or posts to be driven into the ground.
Another object of the present invention is to provide a structure which may be assembled and disassembled in a matter of minutes and stored in a relatively compact container when not in use.
A further object of the present invention is to set forth an enclosure which is capable of being erected upon uneven terrain.
Finally, an object of the present invention is to provide an enclosure with multiple compartments such that the compartments may be used both for shower and dressing areas.
Additional objects and features of the present invention will become apparent from the following detailed description, taken together with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The drawings consist of the following figures:
FIG. 1 is a side elevation view of the invention;
FIG. 2 is an end elevation view;
FIG. 3 is a top plan view;
FIG. 4 is a side detailed view of the limiter block;
FIG. 5 is a front detailed view of the limiter block; and
FIG. 6 is a cut-away view of the upper support member showing the detailed configuration of the detent mechanism.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 2, there is shown a side view of a preferred embodiment for the portable enclosure. There are four main support members 1 standing essentially upright two of which are located on each side of the enclosure and are restrained in the lateral direction by a cross-member 2 which is pinned in a conventional manner to two of the main support members 1 on each side. In the preferred embodiment, each of the four main support members 1 comprises a multiplicity of shorter support members joined together by joint means and in particular, a lower support member 3 and an upper support member 4 joined together by joint means 5. These lower support members 3 are angled in two planes with respect to a perpendicular to the ground and are then connected to upper support members 4 which maintain and extend the same angle towards the upper portion of the enclosure. The lower support member 3 and the upper support member 4 are joined together at joint A through a known method whereby one of the members is reduced diametrically over three or four inches of its length such that it can be inserted into the inside diameter of the mating member. Joint A shown in FIG. 2 represents such a union of the lower support member 3 and the upper support member 4 as well as Joint B shown in FIG. 1 which represents a similar joint configuration between the lateral support member 6 and the horizontal portion of the upper support member 7.
Now referring to FIG. 1, it can be seen that as the upper support members 4 extend toward the top of the enclosure, they are bent at an angle of approximately 73 degrees from their initially straight position and extend in a horizontal direction until they meet Joint B and then proceed to form a lateral support member 6 which proceeds in a horizontal direction until it meets Joint B on the opposite side of the enclosure. Referring still to FIG. 1, it can be seen that the upper support members 4 and the other members connected to the upper support members 4 are held in a fixed position by the limiter blocks 7 which are shown in detail in FIG. 4, thus there is provided means for connecting the limiter blocks 7 to the lateral support members 6. First, the horizontal portion of the upper support members 4 are passed through the openings 8 in the limiter block 7 and are therefore restrained in their movement in a horizontal and vertical plane. Additionally, each of the upper support members 4 contains a detent means 9 which is shown in detail in FIG. 6. This detent means 9 consists of a spring 10 located inside the upper support member 4, which is connected to a detent 11 which passes through a hole in the upper support member. The detent 11 protrudes outside the upper support member such that it engages the elongated detent opening 12 in the limiter block 7 as the upper support member 4 is pushed into the limiter block 7. While the detent mechanism 9 can be depressed during disassembly, it has been found to be unnecessary, and the limiter blocks 7 may remain positioned on the upper support members 4 during normal storage.
Referring to FIG. 5, the upper support member 4 is passed through the limiter opening 8, and the detent 11 is depressed by the assembler such that the detent 11 passes through the limiter opening 8 and is released into the detent opening 12 which is shown as an elongated hole in FIG. 5. Once this is accomplished the upper support member 4 is not only restrained in the horizontal and vertical directions but is also limited in the rotational plane to the range of a predetermined angle by the restriction of the detent 11 movement within the elongated detent opening 12. This limitation of rotation of the upper support members 4 together with the members that connect to the upper support member 4 is of great advantage when attempting to assemble the enclosure since it predetermines the angles that the support members will assume with respect to one another; and it also makes the enclosure easier to assemble since the members are somewhat restricted in their movement. FIGS. 4 and 5 show the detent 11 in an intermediate position such as when the structure was being assembled. The detent 11 would rotate to the top of the elongated opening 12 when the main support members 1 were fully spread open as shown in FIG. 2.
Referring again to FIG. 4, it can be seen that at the bottom of the limiter block 7 there is shown a shower head bracket 13 which in the preferred embodiment is fixed permanently to one of the limiter blocks 7, thus providing a means for attaching a shower head 14 to the enclosure so that the shower can spray into one of the compartments. Note that the shower head bracket 13 is open at its lower portion so that the hose 15 for the shower head 14 can be passed through this opening, and then the shower head 14 itself can be held by the shower head bracket 13.
In FIG. 2 it will be noted that a multiplicity of adjustable length 16 members, such as chains, are connected between the limiter blocks 7 and the curtain support members 20. The limiter blocks 7 are provided with upper hooks 18 which are fixed to the limiter block 7 by conventional means as shown in FIG. 4. The lower hooks 19 are located in approximately the corners of the curtain support frame 20. In the preferred embodiment, the curtain support frame 20 comprises a multiplicity of support members joined together by joint means and in particular, a divider member 21, and two straight curtain support members 22 and two bent curtain support members 23 wherein the straight and bent curtain support members are fastened at Joint C in a known manner similar to the manner described for Joints A and B above. The divider member 21 is connected perpendicular to each straight curtain support member 22 and provides a means whereby a curtain 25 may be hung from curtain rings 24 and separate the enclosure into separate compartments, as shown in FIGS. 1 and 2.
In the preferred embodiment, the divider member 21 may be moved laterally to adjust the size of the respective compartments depending upon the intended application for the portable enclosure. For purposes of the preferred embodiment, the main structure refers to the upper 4 and lower support members 3, cross-members 2 and lateral members 6 when they are joined together through the limiter blocks 7 in the assembled position. Once this main structure is assembled then the curtain support frame 20 may be suspended by the adjustable length members 16 or chains, as shown in FIG. 1, and thus there is provided means for connecting a portion of each corresponding adjustable length member 16 to a limiter block 7 and connecting an opposing portion to the curtain support frame 20. It can be seen that by adjusting the length of the chain 16 at each of the four corners of the curtain support frame 20 or at the upper hooks 18 of the limiter blocks 7 the assembler can easily adjust the relationship of the curtain support frame 20 to the main structure such that the curtain 25 hanging from the curtain rings 24 which are connected to the curtain support frame 20 match the surrounding terrain. In other words, by adjusting the chains 16 the assembler can adapt the portable enclosure to the ground conditions and grade found at the assembly site. The means for connecting the curtain 25 to the curtain support frame 20 in the preferred embodiment comprises a curtain 25 hung from curtain rings 24 which are in turn connected to the curtain support frame 20 in a conventional manner. The curtain 25 can have various openings, however, the preferred embodiment comprises a one piece curtain 25 which extends completely around the outer perimeter of the curtain support frame 20 and then continues on across the divider member 21 with a slit or opening at the location where the divider member 21 connects to the curtain frame 20. This configuration of the curtain yields two separate compartments for the enclosure.
After the portable enclosure is completely assembled a shower head 14 connected to a hose 15 in a conventional manner may be mounted through the shower head bracket 13 shown in FIG. 5 such that the shower spray may be directed into the corresponding compartment, as shown in FIG. 1.
Referring again to FIGS. 1 and 2, it can be observed that the adjustable length member 16, such as a chain, is angled in two directions from a perpendicular to the ground thereby providing stability for the curtain support frame 20 and curtain 25 once it is in the assembled position.
From the above description it is seen that a portable enclosure is provided which adapts to the surrounding terrain and is stable in the assembled position but may be disassembled and stored conveniently.
Although the preferred embodiment of my invention has been described, it is to be understood that the present disclosure is made by way of example, and that variations are possible without departing from the scope of the claimed subject matter which I regard as my invention. | A portable enclosure which may be erected upon uneven terrain in the outdoors where curtained compartments may be utilized as shower and dressing areas in recreational and camping environments. | 0 |
BACKGROUND OF THE INVENTION
1. Field of Invention
The present invention relates to improved methods of preparing 3-phenoxyazetidines and their 1-carboxamide derivatives. The 3-phenoxyazetidines and 3-phenoxy-1-azetidinecarboxamides have pharmacological activity and use in the pharmaceutical field.
2. Information Disclosure Statement
The preparation of 3-phenoxyazetidines by hydrogenolysis of the corresponding 3-phenoxy-1-(α-methylbenzyl)azetidine or 1-diphenylmethyl-3-phenoxyazetidine is disclosed in U.S. Pat. No. 4,379,151. In that disclosure, 1-diphenylmethyl-3-phenoxyazetidine is derived by reacting phenol and sodium amide followed by reaction of the resulting phenolate with 1-diphenylmethyl-3-methanesulfonyloxyazetidine and the compounds have anorexigenic activity.
Anderson, A. G. and Lok, R. in J. Org. Chem. 37, 3953 (1972) disclosed preparation of 1-benzhydryl-3-methoxy (or ethoxy) azetidine via reaction of 1-diphenylmethyl-3-methanesulfonyloxyazetidine with methyl or ethyl alcohol.
The preparation of certain N-loweralkyl-3-phenoxy-1-azetidinecarboxamides which are useful as anticonvulsants from reaction of 3-phenoxyazetidines and isocyanates is disclosed in U.S. Pat. No. 4,226,861.
The preparation of 3-phenoxy-1-azetidine carboxamides is disclosed in copending application U.S. Ser. No. 409,476 filed Aug. 19, 1982. The compounds have anticonvulsant properties as demonstrated by the same methods as in U.S. Pat. No. 4,226,861
The preparation of N-formyl and N-hydroxymethyl-3-phenoxy-1-azetidinecarboxamides having anticonvulsant activity utilizing certain of the 3-phenoxy-1-azetidine carboxamides in reaction with formic acid or formaldehyde is disclosed in copending application U.S. Ser. No. 414,101 filed Sept. 2, 1982. The compounds have anticonvulsant properties as demonstrated by the same methods as in U.S. Pat. No. 4,226,861.
Features of the method of the present invention absent in the prior art are at least as follows:
(a) The 1-diphenylmethyl-3-phenoxyazetidine precursors are novelly prepared in the present invention from a phenol, alkali metal base and 1-diphenylmethyl-3-alkane (or benzene) sulfonyloxyazetidine using a phase transfer catalyst such as tetrabutylammonium bromide, and
(b) Hydrogenolysis of the 1-diphenylmethyl-3-phenoxyazetidine to remove the protecting group and to produce the 3-phenoxyazetidine in a mixture with diphenylmethane by-product is conducted in the presence of an azetidine-stabilizing amount of a tertiary organic base such as triethylamine to prevent formation of a dimerization product found in the practice of prior art methods, which dimer has the following general structure: ##STR1##
Both features a and b promote high yields and in addition, when the azetidine-stabilizing tertiary organic base is used, a mixture of 3-phenoxyazetidine and by-product diphenylmethane can be used without purification to prepare the carboxamides which can be isolated in relatively pure form by washing out the diphenylmethane. Prior art mixtures wherein no stabilizing amine is used contain about 15 parts by weight of the foregoing Dimer A to 85 parts by weight of the desired 3-phenoxyazetidine. As a result, when this mixture is not purified before reacting with methylisocyanate or nitrourea, in carboxamide preparation, a compound having the structure Dimer B results which is difficult to remove: ##STR2##
OBJECTS AND SUMMARY OF THE INVENTION
The invention is especially concerned with economical procedures for preparing 3-phenoxyazetidines and 3-phenoxy-1-azetidinecarboxamides which novelly employ catalysts or stabilizing agents to improve yields or prevent formation of certain contaminants. The 3-phenoxy-1-azetidines are anorexigenics as disclosed in the aforementioned U.S. Pat. No. 4,379,151 as well as chemical intermediates in the synthesis of 3-phenoxy-1-azetidinecarboxamides which have antidepressant activity as disclosed above and are useful in treating epilepsy.
The 3-phenoxy-1-azetidinecarboxamides prepared by the process of the present invention have the formula: ##STR3## wherein R is selected from the group consisting of hydrogen or loweralkyl; R 1 is selected from the group consisting of hydrogen, fluoro, loweralkyl, loweralkoxy, trifluoromethyl, acetyl or aminocarbonyl, and n is selected from 1 to 3 inclusive wherein R 1 may be the same or different.
The 3-phenoxyazetidine precursors to compounds of Formula I have the formula ##STR4## wherein R 1 and n are as defined above.
The 1-diphenylmethyl-3-phenoxyazetidine precursors to the Formula II compounds have the formula ##STR5## wherein R 2 and n are as defined above and Ph is phenyl or phenyl substituted by non-interfering radicals such as loweralkyl.
In the further definition of symbols in Formulas I, II, and III and where they appear elsewhere throughout this specification and in the claims, the terms have the following significance.
The term "loweralkyl" includes straight and branched chain hydrocarbon radicals of up to eight carbon atoms inclusive and is exemplified by such groups as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tertiary butyl, amyl, isoamyl, hexyl, heptyl, octyl and the like.
The term "loweralkoxy" has the formula O-loweralkyl.
The process of the invention is summarized by chemical equation in Chart 1. Obviously, the process may be stopped after step 1 to give compounds of Formula III or after step 2 to give compounds of Formula II or steps 2 and 3 alone may be employed to produce compounds of Formula I. ##STR6##
It is therefore an object of the present invention to provide an improved process for the preparation of N-lower-alkyl-3-phenoxy-1-azetidinecarboxamides wherein the chemical intermediates are utilized more efficiently, leading to high overall yields.
Another object is to provide a method of producing 3-phenoxyazetidines free of polymerization products with minimal purification requirements.
Additional objects will be apparent to one skilled in the art and still other objects will become apparent hereinafter.
DETAILED DESCRIPTION OF THE INVENTION
A schematic of a detailed procedure illustrating the process for preparation of a mixture of a 3-phenoxyazetidine and by-product diphenylmethane, which process avoids formation of dimerization products found in practice of prior art methods, is presented in Chart II. A similar process schematic for conversion of the 3-phenoxyazetidines to 3-phenoxy-1-azetidinecarboxamides is presented in Chart III. Diphenylmethane may be wholly or partially separated before preparation of the carboxamides as indicated in Chart I.
The benzhydryl-sulfonyloxyazetidines used as starting materials in the preparation of the 1-benzhydryl-3-phenoxy azetidines may be prepared as described by Anderson & Lok, J. Org. Chem. 37, 3953 (1972) or as a solution as in the forepart of Example 1 below and if desired, such solution may be evaporated and the residue crystallized from a suitable solvent such as an isopropyl alcohol-water medium to give crystalline material. The preparation is illustrated in Chart IV.
The 1-benzhydryl-3-hydroxyazetidine hydrochlorides are prepared by the method of Anderson & Lok, ibid. ##STR7##
Briefly stated, the process of the invention is comprised of the following steps:
Step 1, reacting a 1-diphenylmethyl-3-alkane (or benzene) sulfonyloxyazetidine having the formula: ##STR8## wherein Ph is phenyl or phenyl substituted by non-interfering radicals, R 2 is loweralkyl (1-8 C), phenyl or phenyl substituted by non-interfering radicals with a phenol having the formula: ##STR9## wherein R 1 and n are as defined under Formula I, together with an alkali-metal base and a phase transfer catayst, preferably tetra-n-butylammonium bromide in a suitable aprotic solvent; e.g., toluene, to give a solution comprised of a 1-diphenylmethyl-3-phenoxyazetidine having the formula: ##STR10## wherein Ph, R 1 and n are as defined above and thereafter washing the solution with water to remove the phase transfer catalyst, drying the solution and evaporating off the aprotic solvent.
Step 2, reacting the compound prepared in step 1 with hydrogen gas using a suitable hydrogenolysis catalyst, preferably palladium on carbon in a suitable protic solvent, preferably methanol or ethanol, together with an azetidine-stabilizing amount of a tertiary organic base, preferably triethylamine and preferably the amount of tertiary organic base being present in the range of 1 to 50 weight percent, preferably 1 to 10 weight percent based on the weight of the 1-diphenylmethyl-3-phenoxyazetidine and thereafter filtering to remove the catalyst, evaporating to remove the protic solvent to give a residue comprised of by-product diphenylmethane and a 3-phenoxyazetidine having the formula: ##STR11## wherein R 1 and n have the starting values and optionally converting the 3-phenoxyazetidine in the mixture to an addition salt and washing out the diphenylmethane with an aprotic solvent to give a 3-phenoxyazetidine salt, and
Step 3, reacting the 3-phenoxyazetidine in the mixture with diphenylmethane prepared in step 2 with nitrourea or loweralkyl isocyanate in an aprotic solvent, preferably toluene, to give a compound having the formula: ##STR12## wherein R is hydrogen or loweralkyl and R 1 and n are as defined above and separating the diphenylmethane.
Prior to conducting step 3, a trace of protic solvent is preferably removed by azeotroping it off with the same aprotic solvent used in step 3.
The tertiary organic bases used to stabilize the azetidine in step 2 may vary widely and it is only necessary that they are sufficiently soluble in the protic hydrogenolysis solvent to protect the azetidine against dimerization and are illustrated by the following: triethylamine, trimethylamine, tri-n-propylamine, tri-n-butylamine, dimethylaniline, dimethylbenzylamine, N-methylmorpholine, N-methyl-piperidine and N-methyl-pyrrolidine and the like. Triethylamine and trimethylamine are preferred because of their volatility and low cost but volatility is not a prerequisite.
The following Examples 1-7 and preceding description and charts serve to illustrate the process of the invention. Examples 8 and 9 form basis for comparing with products of prior art procedures. The scope of the invention is not limited to the examples of the process, however.
EXAMPLE 1
1-(Diphenylmethyl)-3-[3-(trifluoromethyl)phenoxy azetidine.
Preparation of 1-benzhydryl-3-methanesulfonyloxyazetidine in solution
To a stirred solution of 41.33 g (0.15 mole) of N-diphenylmethyl-3-hydroxyazetidine hydrochloride, 42 ml (0.30 mole) of triethylamine in 250 ml of toluene was added 12 ml (0.15 mole) of methanesulfonylchloride dropwise over a 10 min period while maintaining the temperature between 4° to 12° C. After 1 hour, thin-layer chromatography (silica gel, 10% ethylacetate in methylene chloride) showed all starting materials had reacted. The mixture was filtered to remove triethylamine hydrochloride which was washed twice with toluene. The filtrate and washings were combined and measured about 450 ml of solution containing the title compound in theoretical (i.e. about 100%) yield.
To the foregoing toluene solution containing the 1-benzhydryl-3-methanesulfonyloxyazetidine was added 27.5 g (0.17 mole) of 3-trifluoromethylphenol, 2.4 g of tetrabutylammonium bromide, 24 g (0.3 mole) of sodium hydroxide and 24 ml of water and the mixture was stirred vigorously and heated to reflux under nitrogen atmosphere for 2.5 hr. The toluene layer was separated, washed once with water, dried over sodium sulfate and evaporated to give an oil residue. The oil was seeded and subjected to vacuum with an oil pump for about 15 hr. The solid cake obtained contained 49.7 g (86.6%) of the title compound. A portion of the solid cake was dissolved in isopropanol with brief heating. Water was added to cloud point and the mixture was seeded and cooled to cause crystallization. White solid was collected by filtration and washed with 50% aqueous isopropanol and dried under vacuum overnight. NMR showed slight contamination by silicon oil. The melting point found was 82.5°-84° C.
Analysis: Calculated for C 23 H 20 NOF 3 : C,72.05; H,5.26; N,3.65. Found: C,71.62; H,5.29; N,3.61.
EXAMPLE 2
When in the procedure of Example 1, equal molar amounts of the following are substituted for 3-trifluoromethylphenol:
phenol,
2-(trifluoromethyl)phenol,
4-(trifluoromethyl)phenol,
2-(carboxamido)phenol,
3-(carboxamido)phenol,
4-(carboxamido)phenol,
4-methylphenol,
4-methoxyphenol,
3,5-dimethoxyphenol,
3-fluorophenol, and
4-acetylphenol,
there are obtained:
1-(diphenylmethyl)-3-(phenoxy)azetidine,
1-(diphenylmethyl)-3-[2-(trifluoromethyl)phenoxy]azetidine,
1-(diphenylmethyl)-3-[4-(trifluoromethyl)phenoxy]azetidine,
3-[2-(carboxamido)phenoxy]-1-(diphenylmethyl)azetidine,
3-[3-(carboxamido)phenoxy]-1-(diphenylmethyl)azetidine,
3-[4-(carboxamido)phenoxy]-1-(diphenylmethyl)azetidine,
1-(diphenylmethyl)-3-[4-(methyl)phenoxy]azetidine,
1-(diphenylmethyl)-3-[4-(methoxy)phenoxy]azetidine,
1-(diphenylmethyl)-3-[3,5-(dimethoxy)phenoxy]azetidine,
1-(diphenylmethyl)-3-[3-(fluoro)phenoxy]azetidine, and
3-[4-(acetyl)phenoxy]-1-(diphenylmethyl)azetidine.
EXAMPLE 3
3-[3-(Trifluoromethyl)phenoxy]azetidine (and N-cyclohexylsulfamate salt).
1-(Diphenylmethyl)-3-[3-(trifluoromethyl)phenoxy]azetidine, 60 g (0.156 mole), 6 g of 5% palladium-on-carbon hydrogenolysis catalyst, 6 ml of triethylamine and 240 ml of ethanol were shaken under 20-40 psig hydrogen pressure at 60° C. in a Parr bottle for 4 hr, at which time hydrogen uptake ceased. The mixture was filtered to remove the catalyst, using ethanol to wash the filter cake. Toluene was added to the filtrate and this mixture was concentrated first under the reduced pressure of a water aspirator and then under high vacuum provided by an oil pump to give 60.96 g of clear oil which was a mixture of the title compound in quantitative yield, diphenylmethane by-product and a trace of ethanol and toluene. The N-cyclohexylsulfamate salt, prepared from a small portion of the mixture by reacting with hexylsulfamic acid in isopropyl alcohol and recrystallizing from the same solvent, melts at 123°-125° C.
EXAMPLE 4
When in the procedure of Example 3, the following are substituted for 1-(diphenylmethyl)-3-[3-(trifluoromethyl)phenoxy]azetidine:
1-(diphenylmethyl)-3-(phenoxy)azetidine,
1-(diphenylmethyl)-3-[2-(trifluoromethyl)phenoxy]azetidine,
1-(diphenylmethyl)-3-[4-(trifluoromethyl)phenoxy]azetidine,
3-[2-(carboxamido)phenoxy]-1-(diphenylmethyl)azetidine,
3-[3-(carboxamido)phenoxy]-1-(diphenylmethyl)azetidine,
3-[4-(carboxamido)phenoxy]-1-(diphenylmethyl)azetidine,
1-(diphenylmethyl)-3-[4-(methyl)phenoxy]azetidine,
1-(diphenylmethyl)-3-[4-(methoxy)phenoxy]azetidine,
1-(diphenylmethyl)-3-[3,5-(dimethoxy)phenoxy]azetidine,
1-(diphenylmethyl)-3-[3-(fluoro)phenoxy]azetidine, and
3-[4-(acetyl)phenoxy]-1-(diphenylmethyl)azetidine,
there are obtained:
3-(phenoxy)azetidine,
3-[2-(trifluoromethyl)phenoxy]azetidine,
3-[4-(trifluoromethyl)phenoxy]azetidine,
2-(3-azetidinyloxy)benzamide,
3-(3-azetidinyloxy)benzamide,
4-(3-azetidinyloxy)benzamide,
3-[4-(methyl)phenoxy]azetidine,
3-[4-(methoxy)phenoxy]azetidine,
3-[3,5-(dimethoxy)phenoxy]azetidine,
3-[3-(fluoro)phenoxy]azetidine, and
3-[4-(acetyl)phenoxy]azetidine.
EXAMPLE 5
3-[(3-Trifluoromethyl)phenoxy]-1-azetidinecarboxamide.
A mixture containing 5.6 g (0.026 mole) of 3-[3-(trifluoromethyl)phenoxy]azetidine free base and accompanying diphenylmethane by-product and a trace of methanol, all from Example 3, was dissolved in toluene and vacuum distilled, removing the trace of methanol during removal of the toluene. The residue was redissolved in 10 ml of toluene and the solution was cooled in an ice bath. To the cooled solution was added dropwise a solution of 1.54 ml (0.026 mole) of methyl isocyanate in 2 ml of toluene with stirring. The ice bath was removed a few minutes after addition of methyl isocyanate was complete and the mixture was stirred overnight. The mixture solidified and was thereafter subjected to low pressure with an oil vacuum pump to remove any unreacted methyl isocyanate. The white solid was placed on a suction filter and rinsed with toluene. Weight of the title compound was 6.3 g (88%).
EXAMPLE 6
When in the procedure of Example 5, the following are reacted with methyl isocyanate:
3-(phenoxy)azetidine,
3-[2-(trifluoromethyl)phenoxy]azetidine,
3-[4-(trifluoromethyl)phenoxy]azetidine,
2-[3-azetidinyloxy)benzamide,
3-(3-azetidinyloxy)benzamide,
4-(3-azetidinyloxy)benzamide,
3-[4-(methyl)phenoxy]azetidine,
3-[4-(methoxy)phenoxy]azetidine,
3-[3,5-(dimethoxy)phenoxy]azetidine,
3-[3-(fluoro)phenoxy]azetidine, and
3-[4-(acetyl)phenoxy]azetidine,
there are obtained:
3-(phenoxy)-1-azetidinecarboxamide,
3-[2-(trifluoromethyl)phenoxy]-1-azetidinecarboxamide,
3-[4-(trifluoromethyl)phenoxy]-1-azetidinecarboxamide,
3-[2-(aminocarbonyl)phenoxy]-1-azetidinecarboxamide,
3-[3-(aminocarbonyl)phenoxy]-1-azetidinecarboxamide,
3-[4-(aminocarbonyl)phenoxy]-1-azetidinecarboxamide,
3-[4-(methyl)phenoxy]-1-azetidinecarboxamide,
3-[4-(methoxy)phenoxy]-1-azetidinecarboxamide,
3-[3,5-(dimethoxy)phenoxy]-1-azetidinecarboxamide,
3-[3-(fluoro)phenoxy]-1-azetidinecarboxamide, and
3-[4-(acetyl)phenoxy]-1-azetidinecarboxamide.
EXAMPLE 7
3-[3-(Trifluoromethyl)phenoxy]-1-azetidinecarboxamide.
A solution of 6 fold molar excess nitrourea and 3-[3-(trifluoromethyl)phenoxy]azetidine in a 50-50 vol. % mixture of methylene chloride and absolute ethyl alcohol is stirred at room temperature for 48 hr. The mixture is filtered. The filtrate is evaporated to dryness and the residue is partitioned between equal volumes of methylene chloride and water. The water layer is extracted 3 times with methylene chloride. The methylene chloride extracts are combined and evaporated to dryness. The residue is washed with a mixture of 1 vol. of methylene chloride to 20 volumes of toluene and filtered. The precipitate is recrystallized from ethanol/water to give pale yellow crystals. The crystals are triturated with a mixture of 2 volumes methylene chloride to 20 volumes of toluene for 2 hr. White crystals of title compound are obtained, m.p. 151°-152° C.
COMPARATIVE EXAMPLE 8
Following the procedure of Example 3 but omitting triethylamine, 1-(diphenylmethyl)-3-[3-(trifluoromethyl)phenoxy]azetidine was subjected to hydrogenolysis under the same conditions. The mixture was filtered and the filtrate was evaporated to give an oil residue. Mass spectroscopy showed the presence of material having the molecular weight corresponding to the desired product 3-[3-(trifluoromethyl)phenoxy]azetidine and dimerized impurity having a molecular weight of 435 having the structure of ##STR13## From the C 13 NMR spectrum obtained on the mixture, it was estimated from the integrations of the signals that the mixture contained about 15 parts by weight of the dimer to 85 parts by weight of the desired product.
COMPARATIVE EXAMPLE 9
Following the procedure of Example 5, the residue obtained in Example 8 was reacted with methyl isocyanate and the product of the reaction was isolated as a white solid. The white solid contained about 95 wt. % 3-[(3-trifluoromethyl)phenoxy]-1-azetidinecarboxamide. An impurity amounting to about 5 wt. % of the product, the reaction product of the dimer impurity in the starting residue with methyl isocyanate was isolated by thin-layer chromatography and found to have the structure of ##STR14## | An improved process is disclosed for preparing 3-phenoxyazetidines which utilizes a phase transfer catalyst to add the phenoxy group to azetidine blocked in the 1-position by a diphenylmethane group and utilizes a stabilizing tertiary amine base to prevent dimerization during hydrogenolysis to remove the blocking group. The crude product containing diphenylmethane may be used without purification to prepare 3-phenoxy-1-azetidinecarboxamides. | 2 |
FIELD OF THE INVENTION
This invention relates to a process for the purification and separation of exocellular proteins from fermenter broths. More particularly, the invention relates to a process for separating enzymes in solid form, coloring and odor-emitting substances being removed.
STATEMENT OF RELATED ART
Numerous enzymes, especially hydrolases, such as for example proteases, amylases or lipases, are produced by fermentation of microorganisms. Suitable microorganisms and processes for their production are described, for example, in the following patents and patent applications: DE 18 00 508, DE 22 24 777, DE 25 51 742, U.S. Pat. No. 3,827,938, WO 88/01293, DE 18 07 185, U.S. Pat. No. 3,740,318, DE 23 34 463, DE 20 26 092, EP 0 232 169, EP 0 220 921, EP 0 247 647 and EP 0 246 678.
Strongly coloring or strong-smelling impurities are unacceptable for numerous applications, for example for the use of the enzyme solutions in liquid detergents. Accordingly, in the industrial production of the enzymes, the impurities tend to be removed by precipitation processes. However, hitherto known precipitation processes have the disadvantage that considerable losses of yield have to be accepted in order to obtain good color quality. To counteract these difficulties, German patent application P 39 11 099.0 describes a precipitation process in which a masking agent is added to an enzyme solution produced by fermentation and a precipitate is subsequently prepared by adding two water-soluble, mutually precipitating ionic compounds in any order and optionally introducing other adsorbents, for example active carbon.
According to German patent application DE 38 21 151, fermenter broths and/or enzyme solutions are provided with reducing additives in order to reduce odor emission and to improve color quality.
A similar process is described in German patent application P 39 30 284.9, according to which cells of fungi, plants and/or bacteria or cell wall fragments of the above-mentioned organisms are added as selective adsorbents to a fermenter broth. German patent application P 39 15 277.4 also describes a similar process in which an acidic aqueous solution of an aluminum salt and, optionally, additional precipitants are added to the enzyme solution above a pH value between 5 and 11, water-soluble constituents are removed and a masking agent, such as an acid of boron or the like, is added after precipitation.
All the above-mentioned processes are based on the idea of binding the troublesome constituents to the surface of an adsorbent or co-precipitating them with the precipitate of an adsorbent produced in situ, so that an enzyme solution of improved purity remains behind. Although very pure enzyme solutions can be obtained by these processes, the enzyme yield naturally decreases with increasing purification, so that a compromise always has to be made between good quality and good quantity.
It is already known that proteins can be separated from fermenter solutions by precipitation of the proteins themselves rather than the troublesome impurities. However, where the usual precipitants are used in the usual concentrations, the impurities are co-precipitated so that the required purity cannot be obtained in this way.
DESCRIPTION OF THE INVENTION
SUMMARY OF THE INVENTION
The present invention is based on the surprising observation that the concentration precipitation of proteins, particularly hydrolases, is possible when certain substances evidently omnipresent in fermenter broths, which prevent concentration precipitation, are removed by a preliminary treatment with an adsorbent.
Accordingly, the present invention relates to a process for the separation of exocellular proteins of microorganisms from a filtered fermenter broth, characterized in that, in a first step, substances which impede precipitation of the proteins are removed by means of a solid adsorbent, the remaining solution is concentrated to a protein content of around 30 to 40% by weight and the protein is subsequently precipitated at pH values of 6 to 10 and removed, precipitants for proteins optionally being added to accelerate the precipitation process.
It is possible by the process according to the invention to purify numerous proteins which are produced by fermentation of microorganisms and which are present as exocellular proteins in the fermenter broths. For example, it may be used in particular for the production of enzymes, for example for the production of proteases, amylases, cellulases, xylanases, pentosanases or lipases. The process according to the invention is particularly suitable for the production of proteases, particularly alkaline proteases, such as serine proteases.
The fermenter solutions suitable for the process according to the invention preferably emanate from the cultivation of microorganisms, such as bacteria or fungi, more particularly from the cultivation of bacillus strains, for example strains of Bacillus subtilis, Bacillus licheniformis, Bacillus lentus or the like.
DESCRIPTION OF PREFERRED EMBODIMENTS
According to the invention, the fermenter broths are first treated with an adsorbent. To this end, the adsorbent is added in quantities of typically 0.5 to 10% by weight, based on protein solution. Suitable adsorbents are, for example, silicate-containing adsorbents, such as layer silicates, particularly bentonites. Of the bentonites, acid-activated bentonites are particularly suitable. Thus, an acid-activated bentonite having a montmorillonite index of 70 and a fineness of 93%<100 μ may be used as a particularly preferred bentonite.
Instead of or in addition to the bentonites, aluminum oxide hydrates or, quite generally, aluminum salts which form separable precipitates in the pH range around the neutral point of the protein solutions, may also be used as precipitants. Aluminum hydroxychlorides are preferably used as the aluminum salts. In the context of the invention, aluminum hydroxychlorides are understood to be chlorohydroxy compounds of aluminum, for example (Al 2 (OH) 5 Cl) containing 2 to 3 moles of water of crystallization. Preferred materials are technical grades, for example of the type used for the purification of water. Other water-soluble aluminum salts, which form precipitates of aluminum hydroxides when the pH value is raised into the neutral range, are also suitable. The aluminum salts used in accordance with the invention are added to the enzyme solutions in the form of acidic aqueous solutions. These acidic solutions have a pH value of 3 to 4 and a concentration of 10 to 50% by weight. Solutions having a concentration of around 20% by weight have also proved to be favorable. In addition, aluminum hydroxychloride may also be directly stirred into the enzyme solutions in powder form. However, this is less preferred.
The enzyme solutions should have a pH value during the precipitation process in the range from 5 to 11 and preferably in the range from 5 to 8, because, beyond these pH limits, enzyme stability can be adversely affected and, in addition, the precipitant could be partly dissolved again. Accordingly, it is important to ensure that the pH value does not fall below 5 on addition of the precipitant. This may be prevented, for example, by addition of alkaline solutions, for example sodium hydroxide or potassium hydroxide. Buffer solutions may also be added, although they should be adapted to the precipitant.
The quantity of aluminum salt to be used is determined by the degree of purification to be achieved. For many technical applications, quantities of 1 to 5% by weight would appear to be preferable, although purification effects are even obtained with smaller quantities, for example beyond 0.5% by weight. Although larger quantities, for example up to 10% by weight, may be used, they are often not advisable on economic grounds.
In another embodiment of the invention, insoluble calcium salts may also be used for precipitation. It is preferred to produce calcium phosphates in situ in the protein solutions.
The ratio of the calcium salt to the ratio of the phosphorus acid salt is preferably selected so that the molar ratio of calcium to phosphorus is between 1.7 and 2.5:1. It has been found in this regard that calcium phosphates having a predominantly amorphous structure and a large surface are formed under these conditions, representing favorable adsorbents for the colored impurities to be precipitated. The quantity of precipitant, based on enzyme solution, is typically between 0.5 and 20% by weight.
Another adsorbent which may be used in addition to or instead of the adsorbents mentioned is active carbon.
In another embodiment of the invention, a masking agent may be added to the enzyme solutions before or after precipitation. It is preferred to add the masking agent before precipitation because less enzyme activity is lost in this way.
Acids of boron and sulfurous acids and alkali metal salts thereof may be added as masking agents. The quantities to be added are between 0.5 and 5% by weight and preferably between 1 and 3% by weight, based on enzyme solutions, larger quantities being inappropriate primarily on economic grounds. Suitable acids of boron are boric acid, metaboric acid and/or pentaboric acid. Accordingly, particularly suitable alkali metal salts are sodium borate, sodium metaborate, borax or sodium pentaborate. Sodium sulfite is also suitable.
Other suitable masking agents which may be used together with or instead of those mentioned above are dicarboxylic acids and/or hydroxycarboxylic acids containing 3 to 10 carbon atoms. Hydroxydicarboxylic acids, particularly citric acid, tartaric acid and isomers thereof are preferred. The quantity added is between 1 and 5% by weight. In this case, too, larger additions are inappropriate primarily for economic reasons and not because of any reduction in the technical effects obtained.
After the treatment with the adsorbent, the enzyme solution is concentrated. The protein content is preferably adjusted to between 40 and 50% by weight. The pH value of the preparation should be near the neutral point. The pH is preferably adjusted to a value of 7.5 to 9. This applies in particular to hydrolases and more especially to proteases.
Various processes are available to the expert for producing the concentrated enzyme solutions. Thus, micro filtration and/or ultrafiltration may be used and the enzyme solutions obtained may be brought to even higher concentrations either beforehand or afterwards by distilling off water under reduced pressure, for example in a thin film evaporator. In one particularly preferred process, the enzyme solutions are first prepurified by microfiltration and ultrafiltration, subsequently precipitated and finally concentrated by evaporation. In this process, the micro filtration and ultrafiltration steps are carried out in particular as described in German patent application DE 37 30 868. This patent application describes a process for the separation of biotechnologically produced useful materials from a fermenter broth by crossflow microfiltration and/or ultrafiltration using at least two modules arranged in tandem and equipped with porous membranes for each stage, characterized in that a different excess pressure relative to the ambient pressure is applied to each module on the permeate side. To carry out this process, a crossflow rate of more than 4 m/sec is preferably used in the microfiltration stage and inorganic materials, such as aluminum oxide, silicon carbide or zirconium dioxide on a support, are preferably used as the membrane materials.
The concentrated protein solutions prepared in the above-described stages of the process according to the invention are finally subjected to a precipitation step. To this end, the protein is allowed to precipitate in the absence of other substances by cooling the solution to near its freezing point and/or by leaving the solution standing. Thus, it is sufficient in many cases to cool the solution to +5° C. and simply to leave it standing overnight.
It is of course possible also to treat the concentrated protein solution by addition of protein precipitants and then to precipitate the proteins. However, this procedure is not particularly preferred. Suitable protein precipitants are, for example, soluble alkali metal salts, which may be used in quantities of 1 to 5% by weight, water-miscible organic solvents which may be used in quantities of 5 to 20% by weight or water-soluble polymers which may be used in quantities of 0.1 to 5% by weight. Preferred soluble alkali metal salts are sodium chloride, sodium sulfate, calcium chloride and the like. Suitable water-miscible solvents are monohydric and dihydric alcohols such as, for example, ethylene glycol, propylene glycol or even methanol, ethanol or acetone. Suitable water-soluble polymers are polyethylene glycol, polypropylene glycol or polyacrylamide.
The precipitated proteins obtained by the process according to the invention may be further processed in the usual way. Thus, aqueous or aqueous organic protein solutions, for example enzyme concentrate solutions, may be prepared from them. On the other hand, they may also be made up into solid products by drying the precipitated proteins or formulating them together with additives, for example to solid enzyme preparations.
EXAMPLES
Example 1
200 1 of a fermenter broth having a specific protease activity of 34850 HPE/g were prepared by fermentation of a Bacillus licheniformis strain, which produces an exocellular protease of Bacillus lentus, and further processed as follows:
Microfiltration
______________________________________Apparatus:Type Tube modules Pilot plant 2S151, manufactured by TECHSEP, FranceFilter area 2 × 3.4 m.sup.2 (2 modules in tandem)Membrane material Type M14, zirconium oxide on graphiteCutoff limit 0.14 μmOperating conditions:Working temperature 40° C.pH in the retentate 8 Adjusted with 30% NaOHRetentate crossflow 4.8 m/s (= 75 m.sup.3 /h circulation)Retentate inflow 1000 l/hMean transmembranal 0.5 bar Adjusted for each module bypressure correction of the permeate pressure______________________________________
Addition of the precipitant:
An aluminum oxide chloride hydrate (LOCRON®) was added to the protease solution in quantities of 50 g/1. A pH of 8.0 was adjusted with sodium hydroxide.
Preliminary dilution:
The 200 1 of culture solution were diluted with 140 1 of salt solution (NaCl industrial salt, techn. 90%) to reduce the solids content and the viscosity.
______________________________________Salt concentration 10 g/lDilution γ 0.59______________________________________
Diafiltration:
A total of 850 1 of salt solution (NaCl) was added to the retentate while keeping the adjusted concentration factor γ at 0.59.
______________________________________Salt concentration 10 g/lRelative diafiltrate volume 4.25 l/lPermeate flow density 29 l/m.sup.2 hConcentration:Finally, the retentate was concentrated to 170 l.Concentration γ 1.2Result:A total of 1020 l of enzyme-containing permeatewas obtained after diafiltration and concentration.Specific protease activity 4520 HPE/g______________________________________
Ultrafiltration
______________________________________Apparatus:Type Millipore spiral moduleFilter area 5.6 m.sup.2Membrane material PolysulfoneCutoff limit 10,000 daltonsOperating conditions:Working temperature 25° C.Retentate inflow 2500 l/hMean transmembranal pressure 1 bar______________________________________
Concentration:
Concentration is continued to about 30 1. This corresponds to a reduction in volume by a factor of 34, compared with the starting quantity for culture solution
______________________________________ concentration γ 6.6.______________________________________
The permeate flow density falls during concentration from 20 1/m 2 h to 5 1/m 2 h.
______________________________________Result:30 l of concentrateSpecific protease activity 112000 HPE/g______________________________________
Thermal concentration
______________________________________Apparatus:Type α-Laval CTIB-2 Centritherm thin layer evaporatorHeating area 0.09 m.sup.2Evaporator capacity 50 kg/h (water)Operating conditions:Primary steam temperature 80° C.Secondary steam temperature 35° C.Secondary steam pressure 0.01 bar______________________________________
The apparatus has a capacity of 12 kg/h (inflow).
Concentration:
Concentration was continued beyond the usual level. Based on the starting quantity, a reduction in volume by a factor of more than 40 was achieved.
______________________________________Concentration in the stage γ 6Result:4.9 kg DSV concentrate withdry matter 42.4%protease activity 755,000 CPE/g______________________________________
The opaque thin-layer evaporator concentrate was left standing overnight at 5° C. A white precipitate separable in a suction filter was formed and proved to be precipitated enzyme protein.
HPE units:
In the standardized HPE method, the protease is incubated with denatured casein for 15 minutes at 50° C./pH 8.5, excess substrate is precipitated by trichloroacetic acid and the extinction of the alkalized supernatant liquid is measured at 290 nm (soluble aromatic peptides). Under standard conditions, 0.5 extinction units correspond to 10 HPE. The HPE method is comparable with the Anson method.
Enzyme activity unit CPE:
The test principle is based on the proteolytic degradation of N,N-dimethyl casein in sodium sulfite solution at 50° C. and subsequent color reaction of the released amino groups with trinitrobenzene sulfonic acid. The color complex is photometrically quantified at 425 nm and evaluated against a protease standard. | In a process for separating the exocellular proteins from the micro-organisms of a filtered fermentation liquor, the removal of solid is to be improved while retaining the useful substance. This is achieved by, in a first stage, removing substances preventing protein precipitation with the aid of a solid adsorption agent; concentrating the remaining solution to a protein content of about 30 to 40% by weight; and then precipitating and separating the protein, optionally with the addition of precipitants for protein to accelerate the precipitation, at pH values between 6 and 10. | 2 |
RELATED APPLICATIONS
[0001] This application is a divisional of U.S. patent application Ser. No. 09/436,675 filed Nov. 9, 1999, which claims priority of U.S. Provisional Patent Application No. 60/107,627 filed Nov. 9, 1998.
FIELD OF THE INVENTION
[0002] The present invention relates to separation and purification of hydrogen gas from a fluid mixture and, more particularly, to a membrane composition operative as a hydride battery component.
BACKGROUND OF THE INVENTION
[0003] A common technology for extracting high purity hydrogen from industrial gas streams involves selectively diffusing hydrogen through a membrane. High purity hydrogen is used extensively in semiconductor manufacture, fuel cell operation and hydrogenation reactions. Membranes capable of selectively passing hydrogen therethrough have utilized palladium or palladium alloys alone, or supported structurally by a matrix. A suitable hydrogen purification membrane requires a thick enough palladium layer to be made which is free of holes and structurally sound over a working lifetime of at least several months. A palladium-silver membrane is typical of those currently in use. Palladium-silver membranes are limited in their utility due to material costs and limited throughput associated with relatively high resistance to hydrogen permeation. Alternative membrane materials which have been considered as substitutes for palladium-silver have included palladium coated vanadium, niobium, tantalum, and vanadium-nickel. The palladium coat on such membranes functions to increase hydrogen permeation at temperatures below 700° C. and further, to protect the underlying substrate of vanadium, niobium, tantalum or vanadium-nickel from corrosion associated with impurities in the input gas stream. A limitation associated with palladium coated alloys currently under development to supplant palladium-silver is embrittlement upon contact with hydrogen at room temperature. Membrane embrittlement occurs when a membrane unit is rapidly cooled from operating temperature to room temperature. Rapid cooling is associated with power disruption, membrane unit failure, an emergency override situation and the like. Thus, there exists a need to find hydrogen permeable alloys that are more embrittlement resistant than palladium coated vanadium, niobium, tantalum or vanadium-nickel.
[0004] A number of technologies benefit from coating palladium onto surfaces in addition to hydrogen separation. In particular, hydride battery electrodes and bracheotherapy are improved by the present invention.
SUMMARY OF THE INVENTION
[0005] A hydride battery electrode is coated with palladium or a palladium alloy to improve hydride storage properties and recycle characteristics.
[0006] A hydrogen purification membrane including a metallic substrate likewise has improved properties upon coating with palladium and a surface species of an alkali metal, alkaline earth element or alkaline earth cation.
[0007] Novel metal hydrogen purification membranes include vanadium alloyed with at least 1 to 20 atomic percent nickel and/or 1 to 20 atomic percent cobalt and/or 1 to 20 atomic percent palladium.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] Other advantages of the present invention will be readily appreciated by reference to the following detailed description when considered in connection with the accompanying drawings wherein:
[0009] [0009]FIG. 1 is a graph showing the current capacity of a hydride battery electrode uncoated and with a palladium coating according to the present invention, as a function of recharge cycles where Mm denotes misch metal which is at least a binary composition including at least two lanthanide series elements;
[0010] [0010]FIG. 2 is a graph showing the equilibrium potential for an uncoated and palladium coated hydride battery electrode material according to the present invention as a function of recharge cycles;
[0011] [0011]FIGS. 3 a and 3 b are graphs showing the over potential as a function of current for the uncoated electrode ( 3 a ) and the palladium coated electrode ( 3 b ); and
[0012] [0012]FIG. 4 is a graph showing exchange current density as a function of recharge cycles for the materials sampled in FIGS. 3 a and b under linear and tafel polarization conditions.
DETAILED DESCRIPTION OF THE INVENTION
[0013] The present invention also has utility in improving the cycle performance of hydride battery electrodes. As shown in FIG. 1, LaNi 4 7 Al 0.3 shows an exponential capacity decay over approximately 50 cycles as a hydride battery electrode. A more linear decay in performance is observed for the intermetallic alloy Mm 0 95 Ti 0.05 Ni 0 85 Co 0 45 Mn 0 36 Al 0 35 , where Mm includes any two lanthanide series elements. Nonetheless, Mm 0.95 Ti 0.05 Ni 0.85 Co 0 45 Mn 0 36 Al 0.35 does not attain a stable capacity suitable for a rechargeable hydride battery electrode. According to the present invention, coating Mm 0 95 Ti 0.05 Ni 0 85 Co 0 45 Mn 0.36 Al 0 35 with a palladium coating improves electrode performance as compared to uncoated electrode material, as shown in FIGS. 1 - 4 . The electrode is coated with palladium or a palladium alloy, the palladium alloy illustratively forming an intermetallic with main group elements atomic numbers 21-30, 39-45, silver, the lanthanide series, atomic numbers 72-79, boron, and aluminum. Preferably, a palladium or palladium alloy coating according to the present invention is continuous. More preferably, a palladium or palladium alloy coating has a thickness greater than 50 nanometers.
[0014] According to the present invention, the following alloys demonstrate superior embrittlement resistance as compared to prior art substrate materials. Embrittlement resistant alloys of the present invention are characterized by having a bulk vanadium phase which is alloyed with one or more of the following lesser components: nickel to between 1 and 20 atomic percent nickel, 1 to 20 percent cobalt, and 1 to 20 percent palladium. Preferably, alloys of the present invention contain more than 3 and less than 30 total atomic percent of the lesser components: nickel, cobalt and palladium. More preferably, total lesser components account for more than 3 and less than 15 atomic percent. Alloys particularly well suited for application as hydrogen purification membranes illustratively include vanadium-5 atomic percent nickel-5 atomic percent cobalt and vanadium-10 atomic percent palladium. The alloys of the present invention are operative as purification membranes upon forming into a membrane or alternatively at least one side of the alloy membrane is optionally palladium coated.
[0015] A hydrogen permeable membrane according to the present invention containing palladium as an alloy constituent or having a palladium coating has superior hydrogen separation efficiency as compared to prior art membranes through the addition of a quantity of alkali metal or alkaline earth elements as surface deposits thereon. It is appreciated that an alkali metal is deposited on a membrane surface as alkali metal salt. Alkali metal salts illustratively include fluorides, chlorides, bromides and iodides, oxides, sulfides, selenides, nitrides, phosphides, carbonates, nitrates, sulfates, chlorates, chlorites, perchlorates, sulfates, carboxylates, sulfonates, aluminates, borates, chromates, cyanamides, cyanates, cyanides, and the like. An alkaline earth element is applied in the membrane surface either as salts or as zero oxidation state metals. The salts of alkali earth elements operative in the present invention illustratively include: fluorides, chlorides, bromides and iodides, oxides, sulfides, selenides, nitrides, phosphides, carbonates, nitrates, sulfates, chlorates, chlorites, perchlorates, sulfates, carboxylates, sulfonates, aluminates, borates, chromates, cyanamides, cyanates, cyanides, and the like. An alkali earth metal is readily applied to a membrane through conventional methods including evaporative or electrochemical reduction of an alkali earth salt. Of the alkaline earth elements strontium is particularly effective when applied either as a metal or as strontium chloride.
[0016] Electroless deposition of palladium-103 according to the present invention also has utility in bracheotherapy and overcomes limitations associated with prior art electrodeposition as detailed in, for example, U.S. Pat. No. 5,405,309. In this form of bracheotherapy, the radioactive Pd is electrodeposited on a carbon pellet and the Pd-coated pellet is then sealed into a titanium capsule along with an ultrasonic sensitive marker. The marker facilitates proper insertion of the capsule shell within the patient using an ultrasound signal. Typically, several such capsules or “seeds” are inserted into a tumor. Once in the tumor, the seeds irradiate the site locally with a half life of about 17 days, and thereafter may remain in the patient indefinitely. Since the radiation flux decreases dramatically with distance from the seed, there are fewer side effects associated with this method, as compared to external beam irradiation. In a modified form of seed bracheotherapy, the irradiation from the seeds is supplemented by external beam irradiation. For this modified form, it is important that the seeds should not shield the tumor excessively from the irradiating external beam.
[0017] In one embodiment of the instant invention a palladium salt is dissolved in an aqueous or alcoholic solution buffered to a suitable pH for redox chemistry in which the reducing agent acting on the palladium (II) ion is hydrazine. The solution is buffered, for example, through the presence of disodium ethylene diaminetetra acetic acid (EDTA) and soluble alkali metal or alkaline earth chloride salts. Palladium salts operative in electroless deposition of the instant invention illustratively include palladium chloride, palladium chloride dihydrate, palladium nitrate, palladium selenate, palladium sulfate, palladium monoxide hydrate, diamine palladium (II) hydroxide, dichlorodiamine palladium (II), tetramine palladium (II) chloride and tetramine palladium. Tetrachloro palladate (Vauquelin's salt). A buffered solution containing a soluble palladium salt upon the addition of hydrazine begins to plate out palladium metal at a rate increasing with temperature over the solution temperature range from 0 to 100° C. Preferably, the solution temperature during redox chemistry is between 10 and 50° C. Since formation of palladium metal atoms from the ions occurs uniformly throughout a well-mixed solution, uniform coatings of palladium metal result. The pellet substrates operative in the instant invention include a variety of polymeric materials illustratively including cellulose, cellubiose, polyethylene, polycarbonate, polyvinylchloride, polyurethane, DACRON, nylons, TEFLON and the like; graphitic carbon; silicates; aluminates; boron; beryllium; magnesium; and aluminum. For the purposes of this invention a substrate is defined as a material suitable for the deposition adherence of metallic palladium thereto, the shape of the substrate is includes spheroids, ribbons and films. The substrate is the instant invention must also be suitable for encapsulation within a biocompatible shell. It is preferred that in order to build up a thickness of palladium metal and minimize self-shielding of palladium-103 decay by other palladium isotopes, that a layer of nonradioactive palladium be coated onto the pellet substrate, the nonradioactive palladium underlayer serving as a substrate for a second coating, the second coating utilizing 103 Pd containing salts as a reagent. More preferably the pellet substrate is a polymeric material owing in part to the low mass density, low average atomic number and low radiation absorption cross-section, as compared to graphitic carbon and other inorganic materials. The instant invention provides efficient delivery of radiation to the surrounding tissue upon implantation in instances where 103 Pd coated pellets are used alone (bracheotherapy) or when used in combination with external radiation sources. In addition, the polymeric substrates taught herein are flexible and readily formed into a variety of shapes and as a result 103 Pd coated wires, films and otherwise deformable three-dimensional structures are formed which find application in surgical treatment of cancerous tissue as sutures and implantable materials.
[0018] In another embodiment of the instant invention a palladium coating is plated onto a substrate by an immersion deposition process. Immersion deposition in the instant invention utilizes the high reductive electrochemical potential of palladium to displace a reduced substance in contact with the palladium ions. Preferably, the displaced material is a flexible metallic element that is stable in mild acid solutions. Such metals include copper, nickel or iron. Under suitable solution conditions palladium ions displace metallic copper without the need for an additional reducing agent. As an example of immersion deposition of palladium, suitable solution conditions for palladium immersion deposition typically include PdCl 2 or Vauquelin's salt in aqueous solution of pH between 0.1 and 5 in which a low pH is obtained with a mineral acid whose anion is capable of stabilizing copper, nickel or iron ions in solution. Such acids illustratively include hydrochloric and sulfuric.
[0019] While electroless deposition is well suited for depositing a nonradioactive palladium layer, especially on a polymeric substrate, an immersion deposition is preferred for the plating of palladium that is enriched with palladium-103 in amounts suitable for bracheotherapy. Immersion deposition as is completed to electroless deposition is less sensitive to palladium-103 decay to rhodium-103, which accumulates in solution as plating progresses, and thereby degrading to solution.
[0020] The following examples are illustrative of the present invention and not intended to be a limitation on the scope of the invention, which is defined by the appended claims.
EXAMPLE 1
[0021] A 0.010 inch diameter clean V-7%Ni-7%Pd tubular membrane is inserted into a solution containing PdCl 2 dissolved in HCl having a pH of 1.5 and a palladium ion concentration of 1 gram per gallon. A uniform coating of palladium is deposited on the membrane in a matter of minutes at room temperature. The reaction is observed to slow as the copper surface is progressively coated.
EXAMPLE 2
[0022] The process of Example 1 is repeated using Vauquelin's salt in place of palladium chloride. The solution pH is 3.5 prior to the insertion of the membrane wire. The plating is carried out at 50° C. A uniform coating of palladium is deposited on the membrane in a matter of minutes. The plating reaction is observed to slow as the membrane surface is progressively coated.
EXAMPLE 3
[0023] A 0.5 cm diameter rod of Mm 0.95 Ti 0.5 Co 0.45 Mn 0 35 Al 0 35 is coated with 0.5 microns of palladium as recited in Example 1. The resulting palladium coated rod is encapsulated in a solid electrolyte by conventional methods and serves as a hydride electrode.
EXAMPLE 4
[0024] The procedure of Example 3 is repeated with a LaNi 4 7 Al 0.3 rod. Electrode capacity stabilized over 50 charging cycles as compared to the uncoated rod.
EXAMPLE 5
[0025] The procedure of Example 3 is repeated with a LaNi 5 rod. Electrode capacity stabilized over 50 charging cycles as compared to the uncoated rod.
EXAMPLE 6
[0026] A coil of 0.010 inch diameter clean copper wire is inserted into a solution containing PdCl 2 dissolved in HCl having a pH of 1.5 and a palladium ion concentration of 1 gram per gallon. A uniform coating of palladium is deposited on the copper in a matter of minutes at room temperature. The reaction is observed to slow as the copper surface is progressively coated.
EXAMPLE 7
[0027] The process of Example 1 is repeated using Vauquelin's salt in place of palladium chloride. The solution pH is 3.5 prior to the insertion of the copper wire. The plating is carried out at 50° C. A uniform coating of palladium is deposited on the copper in a matter of minutes. The plating reaction is observed to slow as the copper surface is progressively coated.
EXAMPLE 8
[0028] Graphitic carbon pellets are coated with 1-3 microns of nonradioactive copper by conventional electroless deposition techniques with formaldehyde serving as the reducing agent. The copper coated carbon pellets are then washed with deionized water and placed in a solution containing radioactive palladium-103, as recited in Example 1. The resulting radioactive palladium coated pellet is encapsulated in titanium by conventional methods and serves as a bracheotherapy seed.
EXAMPLE 9
[0029] A cellulose based size exclusion separation membrane film approximately 5 mils in thickness is coated first with copper and then with radioactive palladium, as recited in Example 3. The resulting radioactive metallized polymer film is heat sealed in surgical grade TEFLON and is functional as a radioactive suture patch.
[0030] Various modifications of the instant invention in addition to those shown and described herein will be apparent to those skilled n the art from the foregoing description. Such modifications are also intended to fall within the scope of the appended claims. | A hydride battery electrode is coated with palladium or a palladium alloy to improve hydride storage properties and recycle characteristics. A hydrogen purification membrane including a metallic substrate likewise has improved properties upon coating with palladium and a surface species of an alkali metal, alkaline earth element or alkaline earth cation. Novel metal hydrogen purification membranes include vanadium alloyed with at least 1 to 20 atomic percent nickel and/or 1 to 20 atomic percent cobalt and/or 1 to 20 atomic percent palladium. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a polyhydroxyalkanoate (hereinafter, also referred to as “PHA” for short) that comprises a novel structural unit and a process for producing the same. More particularly, the present invention relates to a novel biodegradable PHA that comprises 3-hydroxyalkanoic acid units having a substituted or unsubstituted (phenylmethyl)sulfanyl group at the end of the side chain thereof, and to a process for producing PHAs from an alkanoic acid having a substituted or unsubstituted (phenylmethyl)sulfanyl group at the end of the side chain thereof by using a microorganism capable of producing PHA and accumulating it in the cell.
2. Related Background Art
It has been reported that various microorganisms can produce poly-3-hydroxybutyrate (hereinafter, also referred to as “PHB” for short) or other PHA and accumulate it in the cell (“Biodegradable Plastics Handbook”, Biodegradable Plastics Society Ed., NTS, pages 178-197 (1995)). These polymers may be utilized for production of various products by, for example, melt processing as with conventional plastics, but unlike many conventional synthetic polymer compounds, these polymers do not cause pollution in the natural environment because they are biodegradable, i.e., they are completely degraded by microorganisms in the natural world. Furthermore, they have good biocompatibility and their applications in the medical field as soft materials are expected.
Microbial PHAs are known to have different compositions and/or structures depending on, for example, the type of the microorganism, compositions of the culture medium, and culture conditions. Thus, studies have been done to control the composition and structure to improve physical properties of PHA.
(1) First, the following articles report or disclose synthesis of PHA by polymerization of relatively simple monomer units such as 3-hydroxybutyric acid (hereinafter, abbreviated as 3HB).
For instance, Alcaligenes eutrophus H16 (ATCC No. 17699) and mutants thereof are known to produce copolymers of 3-hydroxybutyrate and 3-hydroxyvalerate (hereinafter, abbreviated as 3HV) with various composition ratios (Japanese Patent Publication No. 6-15604 and Japanese Patent Publication Nos. 7-14352 and 8-19227.)
Japanese Patent No. 2642937 discloses production of PHA of C 6 to C 12 3-hydroxyalkanoate monomer units by feeding acyclic aliphatic hydrocarbon compounds as substrates to Pseudomonas oleovorans (ATCC No. 29347).
Japanese Patent Application Laid-Open No. 5-7492 discloses a process for producing a copolymer of 3HB and 3HV using a microorganism such as Methylobacterium sp., Paracoccus sp., Alcaligenes sp., and Pseudomonas sp. in contact with C 3 to C 7 primary alcohol.
Japanese Patent Application Laid-Open No. 5-93049 and Japanese Patent Application Laid-Open No. 7-265065 disclose production of two-component copolymers of 3HB and 3-hydroxyhexanate by cultivating Aeromonas caviae with oleic acid or olive oil as a substrate.
Japanese Patent Application Laid-Open No. 9-191893 discloses that Comamonans acidovorans IFO 13852 produces polyester containing 3HB and 4-hydroxybutyrate as the monomer units when it is cultivated in the presence of gluconic acid and 1,4-butanediol as substrates.
The above-mentioned PHAs are “usual PHAs” including monomer units having an alkyl group as the side chain thereof, synthesized by microorganisms via β-oxidation of hydrocarbons etc. or via fatty acid synthesis from saccharides.
(2) However, “unusual PHAs”, i.e., PHAs having a substituent other than an alkyl group on the side chain, are expected to be very useful when more extensive application of microbial PHAs is considered, for example, as functional polymers. Certain microorganisms have already been known to produce such “unusual PHAs”, and it has been tried to improve physical properties of microbial PHA with such an approach.
Examples of the substituents include unsaturated hydrocarbons, ester groups, cyano groups, halogenated hydrocarbons, epoxides, and those containing an aromatic ring or rings. Of these, PHAs having an aromatic ring have been studied actively.
For example, Makromol. Chem., 191, 1957-1965 (1990), Macromolecules, 24, 5256-5260 (1991), and Chirality, 3, 492-494 (1991) report that Pseudomonas oleovorans produces PHAs containing 3-hydroxy-5-phenylvalerate (hereinafter, abbreviated as 3HPV) as the monomer unit, where changes in physical properties of the PHA are observed probably due to the presence of 3HPV.
Of the PHAs having a substituent on the side chain thereof, lately those having a phenoxy group on the side chain have been actively developed.
It has been reported that Pseudomonas oleovorans produces from 11-phenoxyundecanoic acids PHA made with monomer units of 3-hydroxy-5-phenoxyvalerate and 3-hydroxy-9-phenoxynonanoate (Macromol. Chem. Phys., 195, 1665-1672 (1994)).
Macromolecules, 29, 3432-3435 (1996) reports production of PHA having monomer units of 3-hydroxy-4-phenoxybutyrate and 3-hydroxy-6-phenoxyhexanoate from 6-phenoxyhexanoic acids; production of PHA having units of 3-hydroxy-4-phenoxybutyrate, 3-hydroxy-6-phenoxyhexanoate, 3-hydroxy-4-phenoxybutyrate, 3-hydroxy-6-phenoxyhexanoate and 3-hydroxy-8-phenoxyoctanoate from 8-phenoxyoctanoic acid; and production of PHA made with units of 3-hydroxy-5-phenoxyvaleric acid and 3-hydroxy-7-phenoxyheptanoic acid from 11-hydroxyundecanoic acid, by using Pseudomonas oleovorans.
Can. J. Microbiol., 41, 32-43 (1995) reports production of PHAs containing 3-hydroxy-6-(4-cyanophenoxy)hexanoic acids or 3-hydroxy-6-(4-nitrophenoxy)hexanoic acid as the monomer units by Pseudomonas oleovorans ATCC 29347 or Pseudomonas putida KT 2422 using octanoic acid and 6-(4-cyanophenoxy)hexanoic acid or 6-(p-nitrophenoxy)hexanoic acid as a substrate.
Of unusual PHAs developed, production of those having sulfur atoms in the form of sulfide (—S—) in the side chain thereof is reported in Macromolecules, 32, 8315-8318 (1999), where Pseudomonas putida 27N01 produced PHAs containing 3-hydroxy-5-(phenylsulfanyl)valeric acid and 3-hydroxy-7-(phenylsulfanyl)heptanoic acid as the monomer units, using octanoic acid and 11-(phenylsulfanyl)undecanoic acid as the substrates. In that case, the Pseudomonas putida 27N01 is pre-cultured in a culture medium containing octanoic acid only as the growth substrate, and then transferred to a culture medium that contains only 11-(phenylsulfanyl)undecanoic acid as a substrate.
Also Polymer Preprints, Japan Vol. 49, No. 5, 1034 (2000) reports production of PHAs containing two monomer units of 3-hydroxy-[(phenylmethyl)sulfanyl]valeric acid and 3-hydroxy-7-[(phenylmethyl)sulfanyl]heptanoic acid, by using Pseudomonas putida 27N01 and 11-[(phenylmethyl)sulfanyl]undecanoic acid as a substrate. In this case also, Pseudomonas putida 27N01 is precultured in a culture medium that contains only octanoic acid as the growth substrate, and then transferred to a culture medium that contains only 11-[(phenylmethyl)sulfanyl]undecanoic acid.
Concerning PHAs containing a 3-hydroxy-ω-[(phenylmethyl)sulfanyl]alkanoic acid unit among unusual PHAs, the above articles are the only reports on the biosynthesis of such PHAs. Further, the available production process is limited. Accordingly, the resulting polymers are not sufficient in types, purity, and yield. In the above process for producing the PHAs containing a 3-hydroxy-ω-[(phenylmethyl)sulfanyl]alkanoic acid unit, the polymer production is conducted by culturing the microorganism in a culture medium containing only ω-[(phenylmethyl)sulfanyl]alkanoic acid having a long carbon chain as the substrate, where ω-[(phenylmethyl)sulfanyl]alkanoic acid is also used as the growth substrate. Therefore, it is difficult to control the structure of the polymer.
PHAs containing a substituted 3-hydroxy-ω-[{[(substituted phenyl)methyl]sulfanyl}alkanoic acid unit that has a substituent such as various functional groups on the benzene ring of (phenylmethyl)sulfanyl group at the end of the side chain are PHAs having novel functionalities, and improvement in physical properties of such PHAs is predicted. Application of such PHAs will be expanded to novel fields where conventional PHAs have not been applicable. Thus, development of an efficient process for producing such PHAs is desired.
SUMMARY OF THE INVENTION
Through the intensive research to solve the above-mentioned problems by the present inventors, this invention was accomplished.
An object of the present invention is to provide a novel PHA and a process for producing the same, in which the PHA comprises a novel unit having a (phenylmethyl)sulfanyl structure in a substituted or unsubstituted side chain thereof.
According to one aspect of the present invention, there is provided a polyhydroxyalkanoate comprising a unit represented by the following chemical formula (1):
wherein R1 is a substituent of an aromatic ring selected from the group consisting of H, CH 3 , C 2 H 5 , CH 3 CH 2 CH 2 , (CH 3 ) 2 CH, (CH 3 ) 3 C, a halogen atom, CN, NO 2 , COOR′, and SO 2 R″, wherein R′ is selected from the group consisting of H, Na, K, CH 3 , and C 2 H 5 , and R″ is selected from the group consisting of OH, a halogen atom, ONa, OK, OCH 3 , and OC 2 H 5 ; and x represents an integer of 1 to 8 being the same or different each other in the polyhydroxyalkanoate, with the proviso that the polyhydroxyalkanoate does not consist of two units represented by the following chemical formulae (2) and (3):
According to another aspect of the present invention, there is provided a process for producing a polyhydroxyalkanoate that comprises a unit represented by the chemical formula (1) comprising the step of cultivating a microorganism in a culture medium containing a compound represented by the following chemical formula (10):
wherein R2 is a substituent of an aromatic ring and selected the group consisting of H, CH 3 , C 2 H 5 , CH 3 CH 2 CH 2 , (CH 3 ) 2 CH, (CH 3 ) 3 C, a halogen atom, CN, NO 2 , COOR′ and SO 2 R″, wherein R′ is selected from the group consisting of H, Na, K, CH 3 , and C 2 H 5 , and R″ is selected from the group consisting of OH, a halogen atom, ONa, OK, OCH 3 , and OC 2 H 5 ; and k represents an integer of 1 to 8.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the 1 H NMR spectrum of a polyhydroxyalkanoate obtained in Example 1;
FIG. 2 shows the 13 C NMR spectrum of the polyhydroxyalkanoate obtained in the Example 1;
FIG. 3 shows the 1 H NMR spectrum of a polyhydroxyalkanoate obtained in Example 10;
FIG. 4 shows the 1 H NMR spectrum of a PHA obtained in Example 19;
FIG. 5 shows the 13 C NMR spectrum of the PHA obtained in the Example 19; and
FIG. 6 shows the 1 H NMR spectrum of a PHA obtained in Example 29.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A novel polyhydroxyalkanoate according to the present invention has a substituted or unsubstituted (phenylmethyl)sulfanyl structure on the side chain of a unit hydroxyalkanoic acid. This structure provides physical and chemical properties that are significantly different from those of known microbial polyhydroxyalkanoates.
The novel polyhydroxyalkanoate according to the present invention can be produced by the steps of: culturing a PHA producing microorganism in a culture medium containing a growth substrate and a substituted or unsubstituted ω-[(phenylmethyl)sulfanyl]alkanoic acid as a feedstock; and recovering polyhydroxyalkanoate containing units having a substituted or unsubstituted (phenylmethyl)sulfanyl group at the end of the side chain thereof, the polyhydroxyalkanoates being produced by accumulated in the microorganism during the cultivation step. In the microbial PHAs, the carbons at the 3 position of all 3-hydroxyalkanoic acid units including those represented by the chemical formula (1) are asymmetric carbons whose absolute configuration is R, indicating the biodegradability thereof.
Examples of the halogen atom in the substituent R on the benzene ring in the above general formulae (1) and (10) include fluorine, chlorine, and bromine.
The present invention is described more in detail below.
PHA-Producing Microorganisms
In the process for producing PHAs according to the present invention, any microorganisms can be used to produce PHA containing a unit having a substituted or unsubstituted (phenylmethyl)sulfanyl group at the end of the side chain thereof represented by the chemical formula (1) (hereinafter referred to as the subject PHA) so long as it can produce the subject PHA and accumulate it in the cells when cultivated in a culture medium containing a corresponding ω-[(phenylmethyl)sulfanyl]alkanoic acid represented by the chemical formula (10) as the source compound. For example, the microorganisms may be those belonging to the genus Pseudomonas having PHA-producing capabilities.
Examples of suitable microorganisms of genus Pseudomonas include the following three strains: Pseudomonas cichorii YN2 (FERM BP-7375), Pseudomonas cichorii H45 (FERM BP-7374), and Pseudomonas jessenii P161 (FERM BP-7376). These three microorganisms was first deposited as the national deposit by the applicant, and is deposited as the international deposit under the Budapest Treaty under the above-mentioned accession numbers in International Patent Organism Depositary, National Institute of Advanced Industrial Science and Technology, Independent Administrative Institution, Ministry of Economy, Trade and Industry 1-3, Higashi 1-chome, Tsukuba-shi, Ibaraki-ken, 305 JAPAN (former National Institute of Bioscience and Human-Technology (NIBH) of the Agency of Industrial Science and Technology, Ministry of Economy, Trade and Industry). They are also described in Japanese Patent Application No. 11-371863 (Japanese Patent Application Laid-Open No. 2001-178484) as novel strains capable of producing PHAs.
Bacteriological properties of the strains YN2, H45, and P161 are given below.
Bacteriological Properties of Strain YN2
(1) Morphological Properties
Shape and size of cells: rod, 0.8 μm×1.5 to 2.0 μm
Polymorphism of cells: negative
Mobility: motile
Sporulation: negative
Gram staining: negative
Colony shape: circular; entire, smooth margin; low
convex; smooth surface; glossy; translucent
(2) Physiological Properties
Catalase: positive
Oxidase: positive
O/F test: oxidative (non-fermentative)
Nitrate reduction: negative
Indole production: positive
Acid production from glucose: negative
Arginine dihydrolase: negative
Urease: negative
Esculin hydrolysis: negative
Gelatin hydrolysis: negative
β-Galactosidase: negative
Fluorescent pigment production on King's B agar: positive
Growth under 4% NaCl: positive (weak growth)
Poly-β-hydroxybutyrate accumulation: negative (*)
Tween 80 hydrolysis: positive
(*) Colonies cultured on nutrient agar were stained with Sudan Black for determination.
(3) Substrate Assimilation
Glucose: positive
L-Arabinose: positive
D-Mannose: negative
D-Mannitol: negative
N-Acetyl-D-glucosamine: negative
Maltose: negative
Potassium gluconate: positive
n-Caprate: positive
Adipate: negative
dl-Malate: positive
Sodium citrate: positive
Phenyl acetate: positive
Bacteriological Properties of Strain H45
(1) Morphological Properties
Shape and size of cells: rod, 0.8 μm×1.0 to 1.2 μm
Polymorphism of cells: negative
Mobility: motile
Sporulation: negative
Gram staining: negative
Colony shape: circular; entire, smooth margin; low convex; smooth surface; glossy; cream-colored
(2) Physiological Properties
Catalase: positive
Oxidase: positive
O/F test: oxidative
Nitrate reduction: negative
Indole production: negative
Acid production from glucose: negative
Arginine dihydrolase: negative
Urease: negative
Esculin hydrolysis: negative
Gelatin hydrolysis: negative
β-Galactosidase: negative
Fluorescent pigment production on King's B agar: positive
Growth under 4% NaCl: negative
Poly-β-hydroxybutyrate accumulation: negative
(3) Substrate Assimilation
Glucose: positive
L-Arabinose: negative
D-Mannose: positive
D-Mannitol: positive
N-Acetyl-D-glucosamine: positive
Maltose: negative
Potassium gluconate: positive
n-Caprate: positive
Adipate: negative
d1-Malate: positive
Sodium citrate: positive
Phenyl acetate: positive
Bacteriological Properties of Strain P161
(1) Morphological Properties
Shape and size of cells: sphere, φ0.6 μm, rods, 0.6
μm×1.5 to 2.0 μm
Polymorphism of cells: elongated form
Mobility: motile
Sporulation: negative
Gram staining: negative
Colony shape: circle; entire, smooth margin; low convex; smooth surface; pale yellow
(2) Physiological Properties
Catalase: positive
Oxidase: positive
O/F test: oxidative
Nitrate reduction: positive
Indole production: negative
Acid production from glucose: negative
Arginine dihydrolase: positive
Urease: negative
Esculin hydrolysis: negative
Gelatin hydrolysis: negative
β-Galactosidase: negative
Fluorescent pigment production on King's B agar: positive
(3) Substrate Assimilation
Glucose: positive
L-Arabinose: positive
D-Mannose: positive
D-Mannitol: positive
N-Acetyl-D-glucosamine: positive
Maltose: negative
Potassium gluconate: positive
n-Caprate: positive
Adipate: negative
d1-Malate: positive
Sodium citrate: positive
Phenyl acetate: positive
Cultivation
According to the PHA production method of the present invention, by culturing the above-mentioned microorganism capable of producing PHA in a culture medium containing ω-[(phenylmethyl)sulfanyl]alkanoic acid represented by the above chemical formula (10) as a feedstock, PHA represented by the chemical formula (1) containing 3-hydroxyalkanate units having a substituted or unsubstituted (phenylmethyl)sulfanyl group at the end of the side chain thereof is produced by and accumulated in the cells.
For ordinary culture of the microorganisms used in the present invention, for example, for preparation of stock strains, or for obtaining cells or maintaining activities required in PHA production, culture media are selected to contain ingredients necessary for the proliferation of the microorganisms used. For example, any one of known culture media, such as typical natural culture media (e.g., nutrient broth, yeast extract) and synthetic culture media supplemented with nutrients, may be used as long as the culture medium does not adversely affect the growth and survival of the microorganisms. Cultivation conditions such as temperature, aeration and agitation are appropriately selected depending on the microorganisms used.
In order to produce the subject PHA by using the PHA-producing microorganism as described above, an inorganic culture medium may be used that contains at least a growth substrate for the microorganism and a compound represented by the above chemical formula (10) corresponding to the monomer unit as the feedstock for PHA production. It is desirable that the compound represented by the above chemical formula (10) be contained in an amount of 0.01% to 1% (w/v), and more preferably 0.02% to 0.2%, per a culture medium. The compound represented by the chemical formula (10) does not always have good water solubility. However, with the microorganisms indicated herein, suspension would cause no trouble.
The feedstock compound represented by the chemical formula (10) may be, in some cases, added to the culture medium as a solution or suspension in a solvent such as 1-hexadecene or n-hexadecane in order to improve dispersibility. In such a case, the concentration of the solvent is required to be equal to or lower than 3% (v/v) relative to the solution of the culture medium.
It is preferable to add a growth substrate for microbial proliferation to the culture medium separately. As the growth substrate, nutrients such as yeast extract, polypeptone, and meat extract may be used. The growth substrate may be selected based on the usefulness as the substrate to the strain to be used, from saccharides, organic acids generated in the TCA cycle, organic acids or salts thereof generated from the biochemical reactions one or two steps later than the TCA cycle, amino acids or salts thereof, C 4 to C 12 straight chain alkanoic acids or salts thereof.
One or more saccharides may suitably be used selected from aldose such as glyceraldehyde, erythrose, arabinose, xylose, glucose, galactose, mannose, and fructose; alditol such as glycerol, erythritol, and xylitol; aldonic acids such as gluconic acid; uronic acid such as glucuronic acid and galacturonic acid; and disaccharide such as maltose, sucrose, and lactose.
As the organic acids or salts thereof, one or more compounds may suitably be selected from pyruvic acid, malic acid, lactic acid, citric acid, succinic acid, and salts thereof.
As the amino acids or salts thereof, one or more compounds may suitably be selected from glutamic acid, aspartic acid, and salts thereof.
Of these, polypeptone and saccharides are preferable. Preferable saccharides include at least one selected from glucose, fructose, and mannose. Preferably, the substrate is contained in an amount of 0.1% to 5% (w/v), and more preferably 0.2% to 2% in the culture medium.
Sometimes the microbial PHA productivity is improved when the microorganism is fully grown and then transferred to a culture medium in which nitrogen source such as ammonium chloride is limited and a compound serving as a substrate for PHA is added. For example, a multi-step approach may be used that performs two or more steps successively under different cultivation conditions.
More specifically, a microorganism is grown in a culture medium that contains a compound represented by the chemical formula (10) and polypeptone until from late logarithmic phase to stationary phase (step 1-1), and then collected by using, for example, centrifugation. Subsequently, the microorganism cultivated in the step 1 is further cultivated in a culture medium that contains a compound represented by the chemical formula (10) and an organic acid or a salt thereof as described above (preferably without a nitrogen source) (step 1-2). Alternatively, the microorganism is cultured in a culture medium that contains a compound represented by the chemical formula (10) and a saccharide as described above until from late logarithmic phase to stationary phase (step 1-3), and collected by using, for example, centrifugation. Subsequently, the microorganism grown in the step 1 is further cultivated in a culture medium that contains the compound represented by the chemical formula (10) and a saccharide as described above (preferably without a nitrogen source) (step 1-4). In the first step of this two-step cultivation procedure, the cells are allowed to proliferate while producing the subject PHA from the feedstock compound represented by the above general formula (10). In the second step, the well-proliferated cells continue PHA production in the culture medium containing no nitrogen source to increase the amount of the PHA accumulated in the cells.
The cultivation temperature should be a temperature at which the above-mentioned strains can proliferate well. For example, the cultivation temperature may be 15° C. to 40° C., preferably 20° C. to 35° C., and more preferably 20° C. to 30° C.
The cultivation may be performed by any suitable cultivation techniques such as liquid or solid cultivation, with which the above-mentioned microorganisms can proliferate to produce polyhydroxyalkanoates. Furthermore, the type of the cultivation is not limited as long as oxygen is supplied properly. Examples include batch cultivation, fed batch cultivation, semi-continuous cultivation, and continuous cultivation. In liquid batch cultivation, the oxygen may be supplied while shaking the content of a shake flask. Alternatively, the oxygen may be supplied by means of an agitation-ventilation method using a jar fermenter.
As the inorganic culture medium to be used for the above-mentioned cultivation procedure, any culture medium may be used that contains ingredients that are required for the proliferation of the microorganisms, such as a phosphorous source (e.g., phosphates) and a nitrogen source (e.g., ammonium salts, nitrates). For example, MSB medium and M9 medium may be used.
The composition of an inorganic culture medium (M9 medium) that is used in a process according to the present invention is given below.
(M9 Medium)
Na 2 HPO 4
6.2 g
KH 2 PO 4
3.0 g
NaCl
0.5 g
NH 4 Cl
1.0 g
(in 1 liter culture medium; pH 7.0)
In order to ensure good proliferation, and production of the polyhydroxyalkanoates, it is necessary to add a trace ingredient solution that is indicated below in an amount of about 0.3% (v/v) to the above-mentioned inorganic culture medium.
(Trace Ingredient Solution)
Nitrilotriacetic Acid: 1.5 g; MgSO 4 : 3.0 g;
MnSO 4 : 0.5 g; NaCl: 1.0 g; FeSO 4 : 0.1 g; CaCl 2 : 0.1 g; CoCl 2 : 0.1 g; ZnSO 4 : 0.1 g; CuSO 4 : 0.1 g; AlK(SO 4 ) 2 : 0.1 g; H 3 BO 3 : 0.1 g; Na 2 MoO 4 : 0.1 g; NiCl 2 : 0.1 g (1-liter solution; pH 7.0)
PHA Recovery
The microorganism used in the present invention produces and accumulates the subject PHA in the cell. Therefore, in the PHA production process of the present invention, a step of recovering the subject PHA from the cells is provided after the cultivation.
For the purpose of recovering the PHA from the cells, a solvent extraction technique is used, in which a solubilized polyhydroxyalkanoate is separated from insoluble cell components. A standard chloroform extraction technique is the most convenient and simple but a solvent other than chloroform may be used such as dichloromethane, dioxane, tetrahydrofuran, acetonitrile, and acetone.
In environments where it is difficult to use an organic solvent, components of the strains other than the polyhydroxyalkanoates are removed by treating with, for example, a surfactant such as SDS, with an enzyme such as lysozyme, or with EDTA and cellular components are removed to recover only the polyhydroxyalkanoates. Alternatively, one can use cell disruption treatment such as ultrasonic disruption, homogenization, pressure disruption, disruption with glass beads, trituration, grinding and freeze-thawing to separate and recover the polyhydroxyalkanoates accumulated in the cells.
It should be understood that the cultivation of the microorganisms of the present invention, the production of the polyhydroxyalkanoates by the microorganisms of the present invention and accumulation of the polyhydroxyalkanoates in the cell, and the recovery of the polyhydroxyalkanoates from the cell are not limited to the above-mentioned techniques and procedures.
The polyhydroxyalkanoates that are produced by the microorganisms according to the process of the present invention may comprise, in addition to the units represented by the chemical formula (1), 3-hydroxyalkanoic acid units represented by the chemical formula (4) or 3-hydroxyalk-5-enoic acid units represented by the chemical formula (5) that is biosynthesized through a fatty acid synthesizing system by using a proliferation substrate to be added to the culture medium. The carbons at the 3 position of all 3-hydroxyalkanoic acid units contained are asymmetric carbons whose absolute configuration is R, indicating the biodegradability thereof. The presence of the (phenylmethyl)sulfanyl group in the units represented by the chemical formula (1) and the presence of the various substituents positioned on the benzene ring thereof provide new physical and chemical properties to the polymers. Improvements in physical properties of such polymers are expected. The polymers can be expanded to the fields to which they were not applicable in the past.
EXAMPLES
The present invention is described specifically below with reference to examples thereof, but not limited thereto. In the following examples, percentages are by weight unless otherwise specified.
Example 1
Pseudomonas cichorii YN2 was inoculated to 200 mL of M9 medium containing 0.5% of D-glucose and 0.1% of 5-[(phenylmethyl)sulfanyl]valeric acid, and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, re-suspended in 200 mL of M9 medium containing 0.5% of D-glucose and 0.1% of 5-[(phenylmethyl)sulfanyl]valeric acid but no nitrogen source (NH 4 Cl), and cultured at 30° C. with shaking at 125 strokes/min for 48 hours. After that, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized.
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 159 mg of polyhydroxyalkanoate.
The polyhydroxyalkanoate was subjected to NMR analysis under the following conditions.
Spectrometer
FT-NMR: Bruker DPX 400 with spectrometer frequencies of 400 MHz for 1 H-NMR and 100 MHz for 13 C.
Conditions
Nuclear Species: 1 H, 13 C
Solvent: CDCl 3
Temperature: room temperature
FIGS. 1 and 2 show 1 H-NMR spectra and 13 C-NMR spectra, respectively, of the polyhydroxyalkanoate. Identification results thereof are given in Tables 1 and 2 below.
TABLE 1
Chemical
Splitting
shifts (ppm)
Integration
patterns
Identification
1.83
2 H
qurt
d1
2.36-2.54
4 H
m
b1, c1
3.67
2 H
s
f1
5.20
1 H
quint
c1
7.20
1 H
m
j1
7.25-7.28
4 H
m
h1, l1 & i1, k1
TABLE 2
Chemical shifts
(ppm)
Identification
26.6
d1
33.0
e1
35.9
f1
38.6
b1
69.7
c1
126.9
j1
128.4
h, l
128.8
i, k
138.0
g1
168.9
a1
As clearly shown by Tables 1 and 2, it was confirmed that the polyhydroxyalkanoate is one represented by the following chemical formula (16) containing, as the monomer units, 3-hydroxy-5-[(phenylmethyl)sulfanyl]valerate, and 3-hydroxyalkanoates and/or 3-hydroxyalkenoates corresponding to saturated/unsaturated fatty acids having 4 to 12 carbon atoms such as 3-hydroxybutyric acid and 3-hydroxyvaleric acid. The integration of the 1 H-NMR spectra indicated that the polyhydroxyalkanoate contains 3-hydroxy-5-[(phenylmethyl)sulfanyl]valerate by 85.9 mol %.
The molecular weight of the polyhydroxyalkanoate was determined by gel permeation chromatography (GPC; TOSOH HLC-8220, column; TOSOH TSK-GEL SuperHM-H (trade name), solvent; chloroform, polystyrene equivalent). As a result, Mn was 14,400 and Mw was 56,700.
Example 2
Pseudomonas cichorii H45 was inoculated to 200 mL of M9 medium containing 0.5% of D-glucose and 0.1% of 5-[(phenylmethyl)sulfanyl]valeric acid, and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, re-suspended in 200 mL of M9 medium containing 0.5% of D-glucose and 0.1% of 5-[(phenylmethyl)sulfanyl]valeric acid but no nitrogen source (NH 4 Cl), and cultured at 30° C. with shaking at 125 strokes/min for 48 hours. After that, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized.
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 138 mg of polyhydroxyalkanoate.
The polyhydroxyalkanoate obtained was subjected to NMR analysis under the same conditions as in the Example 1. As a result, it was revealed that this polyhydroxyalkanoate is one represented by the chemical formula (16) containing, as the monomer units, 3-hydroxy-5-[(phenylmethyl)sulfanyl]valerate, and 3-hydroxyalkanoates and/or 3-hydroxyalkenoates corresponding to saturated/unsaturated fatty acids having 4 to 12 carbon atoms such as 3-hydroxybutyric acid and 3-hydroxyvaleric acid. The integration of the 1 H-NMR spectra indicated that the polyhydroxyalkanoate contains 3-hydroxy-5-[(phenylmethyl)sulfanyl]valerate by 95.2 mol %.
Example 3
Pseudomonas jessenii P161 was inoculated to 200 lb mL of M9 medium containing 0.5% of D-glucose and 0.1% of 5-[(phenylmethyl)sulfanyl]valeric acid, and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, re-suspended in 200 mL of M9 medium containing 0.5% of D-glucose and 0.1% of 5-[(phenylmethyl)sulfanyl]valeric acid but no nitrogen source (NH 4 Cl), and cultured at 30° C. with shaking at 125 strokes/min for 47 hours. After that, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized.
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 164 mg of polyhydroxyalkanoate.
The polyhydroxyalkanoate obtained was subjected to NMR analysis under the same conditions as in the Example 1. As a result, it was revealed that this polyhydroxyalkanoate is one represented by the chemical formula (16) containing, as the monomer units, 3-hydroxy-5-[(phenylmethyl)sulfanyl]valerate, and 3-hydroxyalkanoates and/or 3-hydroxyalkenoates corresponding to saturated/unsaturated fatty acids having 4 to 12 carbon atoms such as 3-hydroxybutyric acid and 3-hydroxyvaleric acid. The integration of the 1 H-NMR spectra indicated that the polyhydroxyalkanoate contains 3-hydroxy-5-[(phenylmethyl)sulfanyl]valerate by 96.7 mol %.
Example 4
Pseudomonas cichorii YN2 was inoculated to 200 mL of M9 medium containing 0.5% of polypeptone (Wako Pure Chemical Industries, Ltd.) and 0.1% of 5-[(phenylmethyl)sulfanyl]valeric acid, and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized.
The lyophilized pellet was suspended in 20 ml of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 161 mg of polyhydroxyalkanoate.
The polyhydroxyalkanoate obtained was subjected to NMR analysis under the same conditions as in the Example 1. As a result, it was revealed that this polyhydroxyalkanoate is one represented by the chemical formula (16) containing, as the monomer units, 3-hydroxy-5-[(phenylmethyl)sulfanyl]valerate, and 3-hydroxyalkanoates and/or 3-hydroxyalkenoates corresponding to saturated/unsaturated fatty acids having 4 to 12 carbon atoms such as 3-hydroxybutyric acid and 3-hydroxyvaleric acid. The integration of the 1 H-NMR spectra indicated that the polyhydroxyalkanoate contains 3-hydroxy-5-[(phenylmethyl)sulfanyl]valerate by 83.8 mol %.
Example 5
Pseudomonas cichorii H45 was inoculated to 200 mL of M9 medium containing 0.5% of polypeptone (Wako Pure Chemical Industries, Ltd.) and 0.1% of 5-[(phenylmethyl)sulfanyl]valeric acid, and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized.
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 113 mg of polyhydroxyalkanoate.
The polyhydroxyalkanoate obtained was subjected to NMR analysis under the same conditions as in the Example 1. As a result, it was revealed that this polyhydroxyalkanoate is one represented by the chemical formula (16) containing, as the monomer units, 3-hydroxy-5-[(phenylmethyl)sulfanyl]valerate, and 3-hydroxyalkanoates and/or 3-hydroxyalkenoates corresponding to saturated/unsaturated fatty acids having 4 to 12 carbon atoms such as 3-hydroxybutyric acid and 3-hydroxyvaleric acid. The integration of the 1 H-NMR spectra indicated that the polyhydroxyalkanoate contains 3-hydroxy-5-[(phenylmethyl)sulfanyl]valerate by 96.2 mol %.
Example 6
Pseudomonas jessenii P161 was inoculated to 200 mL of M9 medium containing 0.5% of polypeptone (Wako Pure Chemical Industries, Ltd.) and 0.1% of 5-[(phenylmethyl)sulfanyl]valeric acid, and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized.
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 126 mg of polyhydroxyalkanoate.
The polyhydroxyalkanoate obtained was subjected to NMR analysis under the same conditions as in the Example 1. As a result, it was revealed that this polyhydroxyalkanoate is one represented by the chemical formula (16) containing, as the monomer units, 3-hydroxy-5-[(phenylmethyl)sulfanyl]valerate, and 3-hydroxyalkanoates and/or 3-hydroxyalkenoates corresponding to saturated/unsaturated fatty acids having 4 to 12 carbon atoms such as 3-hydroxybutyric acid and 3-hydroxyvaleric acid. The integration of the 1 H-NMR spectra indicated that the polyhydroxyalkanoate contains 3-hydroxy-5-[(phenylmethyl)sulfanyl]valerate by 89.8 mol %.
Example 7
Pseudomonas cichorii YN2 was inoculated to 200 mL of M9 medium containing 0.1% of nonanoic acid and 0.1% of 5-[(phenylmethyl)sulfanyl]valeric acid, and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized.
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 90 mg of polyhydroxyalkanoate.
The polyhydroxyalkanoate obtained was subjected to NMR analysis under the same conditions as in the Example 1. As a result, it was revealed that this polyhydroxyalkanoate is one represented by the chemical formula (16) containing, as the monomer units, 3-hydroxy-5-[(phenylmethyl)sulfanyl]valerate, and 3-hydroxyalkanoates and/or 3-hydroxyalkenoates corresponding to saturated/unsaturated fatty acids having 4 to 12 carbon atoms such as 3-hydroxybutyric acid and 3-hydroxyvaleric acid. The integration of the 1 H-NMR spectra indicated that the polyhydroxyalkanoate contains 3-hydroxy-5-[(phenylmethyl)sulfanyl]valerate by 29.2 mol %.
Example 8
Pseudomonas cichorii YN2 was inoculated to 200 mL of M9 medium containing 0.5% of yeast extract, and 0.1% of 5-[(phenylmethyl)sulfanyl]valeric acid, and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized.
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 103 mg of polyhydroxyalkanoate.
The polyhydroxyalkanoate obtained was subjected to NMR analysis under the same conditions as in the Example 1. As a result, it was revealed that this polyhydroxyalkanoate is one represented by the chemical formula (16) containing, as the monomer units, 3-hydroxy-5-[(phenylmethyl)sulfanyl]valerate, and 3-hydroxyalkanoates and/or 3-hydroxyalkenoates corresponding to saturated/unsaturated fatty acids having 4 to 12 carbon atoms such as 3-hydroxybutyric acid and 3-hydroxyvaleric acid. The integration of the 1 H-NMR spectra indicated that the polyhydroxyalkanoate contains 3-hydroxy-5-[(phenylmethyl)sulfanyl]valerate by 96.0 mol %.
Example 9
Pseudomonas cichorii YN2 was inoculated to 200 mL of M9 medium containing 0.5% of sodium glutamate and 0.1% of 5-[(phenylmethyl)sulfanyl]valeric acid, and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized.
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 87 mg of polyhydroxyalkanoate.
The polyhydroxyalkanoate obtained was subjected to NMR analysis under the same conditions as in the Example 1. As a result, it was revealed that this polyhydroxyalkanoate is one represented by the chemical formula (16) containing, as the monomer units, 3-hydroxy-5-[(phenylmethyl)sulfanyl]valerate, and 3-hydroxyalkanoates and/or 3-hydroxyalkenoates corresponding to saturated/unsaturated fatty acids having 4 to 12 carbon atoms such as 3-hydroxybutyric acid and 3-hydroxyvaleric acid. The integration of the 1 H-NMR spectra indicated that the polyhydroxyalkanoate contains 3-hydroxy-5-[(phenylmethyl)sulfanyl]valerate by 86.4 mol %.
Table 3 shows the dry weight of the cells, the dry weight of the polymer, the ratio of the polymer to the cells by dry weight, and the amount (mol %) of the 3-hydroxy-5-[(phenylmethyl)sulfanyl]valerate (abbreviated as “3HBzyTV”) unit in the resulting polymer in Examples 1-9.
TABLE 3
Polymer Dry
3HBzyTV
Cell Dry
Weight
Polymer Weight/
Unit
Weight (mg/L)
(mg/L)
Cell Weight (%)
mol %
Example 1
1070
795
74.3
85.9
Example 2
875
690
78.9
95.2
Example 3
1015
820
80.8
96.7
Example 4
1070
805
75.2
83.8
Example 5
710
565
79.6
96.2
Example 6
940
630
67.0
89.8
Example 7
705
450
63.8
29.2
Example 8
815
515
63.2
96.0
Example 9
995
435
43.7
86.4
Example 10
Process for Producing Polyhydroxyalkanoate Containing 3-Hydroxy-4-[(Phenylmethyl)sulfanyl]Butyrate Monomer Unit
Pseudomonas cichorii YN2 was inoculated to 200 mL of M9 medium containing 0.5% of yeast extract and 0.1% of 4-[(phenylmethyl)sulfanyl]butyric acid, and cultured at 30° C. with shaking at 125 strokes/min for 48 hours. Then, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized. The weight of the lyophilized cells (dry weight of the cells) was weighed.
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 39 mg of polyhydroxyalkanoate.
The average molecular weight of the resulting PHA was determined by gel permeation chromatography (GPC: TOSOH HLC-8220 (trade name), column: TOSOH TSK-GEL SuperHM-H (trade name), solvent: chloroform, polystyrene equivalent). As a result, the number average molecular weight Mn was 44,500 and the weight average molecular weight Mw was 106,800.
In order to identify the structure of the PHA obtained, the PHA was subjected to NMR analysis under the following conditions.
Spectrometer
FT-NMR: Bruker DPX 400 with spectrometer frequency of 400 MHz for 1 H-NMR.
Conditions
Nuclear Species: 1 H
Solvent: CDCl 3
Reference: TMS/CDCl 3 in capillary
Temperature: room temperature
FIG. 3 shows measured 1 H-NMR spectra and identification results thereof are given in Table 4 below.
TABLE 4
Chemical
Splitting
shift (ppm)
Integration
pattern
Identification
2.48-2.71
4 H
m
B5, d5
3.68
2 H
m
e5
5.27
1 H
m
c5
7.18
1 H
m
i5
7.25
4 H
m
g5, k5, h5, j5
The results shown in the Table 4 confirm that this polyhydroxyalkanoate contains as the monomer units, 3-hydroxy-4-[(phenylmethyl)sulfanyl]butyrate, and 3-hydroxyalkanoates and/or 3-hydroxyalkenoates corresponding to saturated/unsaturated fatty acids having 4 to 12 carbon atoms such as 3-hydroxybutyric acid or 3-hydroxyvaleric acid. More specifically, the PHA has a structure represented by the following chemical formula (17):
The integration of the 1 H-NMR spectra indicated that the polyhydroxyalkanoate contains 3-hydroxy-4-[(phenylmethyl)sulfanyl]butyrate by 85.4 mol %.
Example 11
Pseudomonas cichorii YN2 was inoculated to 200 mL of M9 medium containing 0.1% of nonanoic acid and 0.1% of 4-[(phenylmethyl)sulfanyl]butyric acid, and cultured at 30° C. with shaking at 125 strokes/min for 48 hours. Then, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized. The weight of the lyophilized cells was measured (dry weight of the cells).
The lyophilized pellet was suspended in 20 mL, of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 68 mg of polyhydroxyalkanoate.
The polyhydroxyalkanoate obtained was subjected to NMR analysis under the same conditions as in the Example 10. As a result, it was revealed that this polyhydroxyalkanoate is one represented by the chemical formula (17) containing a monomer unit of 3-hydroxy-4-[(phenylmethyl)sulfanyl]butyrate, and other monomer units of 3-hydroxyalkanoates and/or 3-hydroxyalkenoates corresponding to saturated/unsaturated fatty acids having 4 to 12 carbon atoms such as 3-hydroxybutyric acid or 3-hydroxyvaleric acid. The integration of the 1 H-NMR spectra indicated that the polyhydroxyalkanoate contains 3-hydroxy-4-[(phenylmethyl)sulfanyl]butyrate by 27.7 mol %.
Example 12
Pseudomonas cichorii YN2 was inoculated to 200 mL of M9 medium containing 0.5% of sodium glutamate and 0.1% of 4-[(phenylmethyl)sulfanyl]butyric acid, and cultured at 30° C. with shaking at 125 strokes/min for 48 hours. Then, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized. The weight of the lyophilized cells was weighed (dry weight of the cells).
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 72 mg of polyhydroxyalkanoate.
The polyhydroxyalkanoate obtained was subjected to NMR analysis under the conditions as set forth in the Example 10. As a result, it was revealed that this polyhydroxyalkanoate is one represented by the chemical formula (17). The polyhydroxyalkanoate comprises a monomer unit of 3-hydroxy-4-[(phenylmethyl)sulfanyl]butyrate and other monomer units of 3-hydroxyalkanoates and/or 3-hydroxyalkenoates having 4 to 12 carbon atoms such as 3-hydroxybutyrate and 3-hydroxyvaleric acid. The integration of the 1 H-NMR spectra indicated that the resulting polyhydroxyalkanoate contains 50.3 mol % of 3-hydroxy-4-[(phenylmethyl)sulfanyl]butyrate monomer unit.
Example 13
Pseudomonas cichorii YN2 was inoculated to 200 mL of M9 medium containing 0.5% of D-glucose and 0.1% of 4-[(phenylmethyl)sulfanyl]butyric acid, and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, re-suspended in 200 mL of M9 medium containing 0.5% of D-glucose and 0.1% of 4-[(phenylmethyl)sulfanyl]butyric acid but no nitrogen source (NH 4 Cl), and cultured at 30° C. with shaking at 125 strokes/min for 48 hours. After that, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized. The lyophilized cells were weighed (cell dry weight).
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 148 mg of polyhydroxyalkanoate.
The polyhydroxyalkanoate obtained was subjected to NMR analysis under the conditions as set forth in the Example 10. As a result, it was revealed that this polyhydroxyalkanoate is the polyhydroxyalkanoate that is represented by the chemical formula (17). The polyhydroxyalkanoate comprises a monomer unit of 3-hydroxy-4-[(phenylmethyl)sulfanyl]butyrate and other monomer units of 3-hydroxyalkanoicates and/or 3-hydroxyalkenoates having 4 to 12 carbon atoms such as 3-hydroxybutyrate and 3-hydroxyvalerate. The integration of the 1 H-NMR spectra indicated that the resulting polyhydroxyalkanoate contains 66.7 mol % of the 3-hydroxy-4-[(phenylmethyl)sulfanyl]butyrate monomer unit.
Example 14
Pseudomonas cichorii H45 was inoculated to 200 mL of N9 medium containing 0.5% of polypeptone (Wako Pure Chemical Industries, Ltd.) and 0.1% of 5-[(phenylmethyl)sulfanyl]butyric acid, and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized. The weight of the lyophilized cells was weighed (dry weight of the cells).
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 20 mg of polyhydroxyalkanoate.
The polyhydroxyalkanoate obtained was subjected to NMR analysis under the conditions as set forth in the Example 10. As a result, it was revealed that this polyhydroxyalkanoate is one represented by the chemical formula (17). The polyhydroxyalkanoate comprises a monomer unit of 3-hydroxy-4-[(phenylmethyl)sulfanyl]butyrate and other monomer units of 3-hydroxyalkanoates and/or 3-hydroxyalkenoates corresponding to saturated/unsaturated fatty acids having 4 to 12 carbon atoms such as 3-hydroxybutyric acid and 3-hydroxyvaleric acid. The integration of the 1 H-NMR spectra indicated that the resulting polyhydroxyalkanoate contains 57.2 mol % of 3-hydroxy-4-[(phenylmethyl)sulfanyl]butyrate monomer unit.
Example 15
Pseudomonas jessenii P161 was inoculated to 200 mL of M9 medium containing 0.5% of D-glucose and 0.1% of 5-[(phenylmethyl)sulfanyl]valeric acid, and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, re-suspended in 200 mL of M9 medium containing 0.5% of D-glucose and 0.1% of 5-[(phenylmethyl)sulfanyl]valeric acid but no nitrogen source (NH 4 Cl), and cultured at 30° C. with shaking at 125 strokes/min for 48 hours. After that, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized. The weight of the lyophilized cells was weighed (the cell dry weight).
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 64 mg of polyhydroxyalkanoate.
The polyhydroxyalkanoate obtained was subjected to NMR analysis under the conditions as set forth in the Example 10. As a result, it was revealed that this polyhydroxyalkanoate is one represented by the chemical formula (17). The polyhydroxyalkanoate comprises a monomer unit of 3-hydroxy-4-[(phenylmethyl)sulfanyl]butyrate and other monomer units of 3-hydroxyalkanoates and/or 3-hydroxyalkenoates corresponding to saturated/unsaturated fatty acids having 4 to 12 carbon atoms such as 3-hydroxybutyric acid and 3-hydroxyvaleric acid. The integration of the 1 H-NMR spectra indicated that the resulting polyhydroxyalkanoate contains 31.6 mol % of 3-hydroxy-4-[(phenylmethyl)sulfanyl]butyrate monomer unit.
Table 5 shows the dry weight of the cells, the dry weight of the polymer, the dry weight ratio of the polymer to the cells, and the amount (mol %) of 3-hydroxy-4-[(phenylmethyl)sulfanyl]butyrate (abbreviated as “3HBzyTB” units) in the resulting polymer in Examples 10-15.
TABLE 5
Cell Dry
3HBzyTB
Weight
Polymer Dry
Polymer Weight/
Unit
(mg/L)
Weight (mg/L)
Cell Weight (%)
mol %
Example 10
1040
195
18.8
85.4
Example 11
655
340
51.9
27.7
Example 12
955
360
37.7
50.3
Example 13
1370
740
54.0
66.7
Example 14
580
100
17.2
57.2
Example 15
915
320
35.0
31.6
Process for Producing Polyhydroxyalkanoate containing 3-Hydroxy-5-{[(4-Methylphenyl)methyl]Sulfanyl} Valerate Monomer Unit
Example 16
Pseudomonas cichorii YN2 was inoculated to 200 mL of M9 medium containing 0.5% of D-glucose and 0.1% of 5-[[(4-methylphenyl)methyl]sulfanyl]valeric acid, and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, re-suspended in 200 mL of M9 medium containing 0.5% of D-glucose and 0.1% of 5-[[4-methylphenyl)methyl]sulfanyl]valeric acid but no nitrogen source (NH 4 Cl), and cultured at 30° C. with shaking at 125 strokes/min for 48 hours. After that, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized.
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 96 mg of polyhydroxyalkanoate.
The polyhydroxyalkanoate obtained was subjected to NMR analysis under the conditions as set forth in Example 10. As a result, it was revealed that this polyhydroxyalkanoate is one represented by the chemical formula (18). The polyhydroxyalkanoate comprises a monomer unit of 3-hydroxy-5-[[(4-methylphenyl)methyl]sulfanyl]valerate and other monomer units of 3-hydroxyalkanoates and/or 3-hydroxyalkenoates corresponding to saturated/unsaturated fatty acids having 4 to 12 carbon atoms such as 3-hydroxybutyric acid and 3-hydroxyvaleric acid. The integration of the 1 H-NMR spectra indicated that the resulting polyhydroxyalkanoate contains 41.0 mol % of 3-hydroxy-5-{[(4-methylphenyl)methyl]sulfanyl}valerate monomer unit.
The molecular weight of the resulting polyhydroxyalkanoate was determined by gel permeation chromatography (GPC; TOSOH HLC-8220, column; TOSOH TSK-GEL SuperHM-H, solvent; chloroform, polystyrene equivalent). As a result, Mn was 21,500 and Mw was 83,200.
Example 17
Pseudomonas cichorii H45 was inoculated to 200 mL of M9 medium containing 0.5% of D-glucose and 0.1% of 5-[[(4-methylphenyl)methyl)sulfanyl]valeric acid, and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, re-suspended in 200 mL of M9 medium containing 0.5% of D-glucose and 0.1% of 5-[[4-methylphenyl)methyl]sulfanyl]valeric acid but no nitrogen source (NH 4 Cl), and cultured at 30° C. with shaking at 125 strokes/min for 48 hours. After that, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized.
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 82 mg of polyhydroxyalkanoate.
The polyhydroxyalkanoate obtained was subjected to NMR analysis under the conditions as set forth in Example 10. As a result, it was revealed that this polyhydroxyalkanoate is one represented by the chemical formula (18). The polyhydroxyalkanoate comprises a monomer unit of 3-hydroxy-5-[[(4-methylphenyl)methyl]sulfanyl]valerate and other monomer units of 3-hydroxyalkanoates and/or 3-hydroxyalkenoates corresponding to saturated/unsaturated fatty acids having 4 to 12 carbon atoms such as 3-hydroxybutyric acid and 3-hydroxyvaleric acid. The integration of the 1 H-NMR spectra indicated that the resulting polyhydroxyalkanoate contains 56.2 mol % of 3-hydroxy-5-[[(4-methylphenyl)methyl]sulfanyl]valerate monomer unit.
Example 18
Pseudomonas jessenii P161 was inoculated to 200 mL of M9 medium containing 0.5% of D-glucose and 0.1% of 5-[[(4-methylphenyl)methyl]sulfanyl]valeric acid, and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, re-suspended in 200 mL of M9 medium containing 0.5% of D-glucose and 0.1% of 5-[[4-methylphenyl)methyl]sulfanyl]valeric acid but no nitrogen source (NH 4 Cl), and cultured at 30° C. with shaking at 125 strokes/min for 48 hours. After that, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized.
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 75 mg of polyhydroxyalkanoate.
The polyhydroxyalkanoate obtained was subjected to NMR analysis under the conditions as set forth in Example 10. As a result, it was revealed that this polyhydroxyalkanoate is one represented by the chemical formula (18). The polyhydroxyalkanoate comprises a monomer unit of 3-hydroxy-5-[[(4-methylphenyl)methyl]sulfanyl]valerate and other monomer units of 3-hydroxyalkanoates and/or 3-hydroxyalkenoates corresponding to saturated/unsaturated fatty acids having 4 to 12 carbon atoms such as 3-hydroxybutyric acid and 3-hydroxyvaleric acid. The integration of the 1 H-NMR spectra indicated that the resulting polyhydroxyalkanoate contains 38.8 mol % of 3-hydroxy-5-{[(4-methylphenyl)methyl]sulfanyl}valerate monomer unit.
Table 6 shows the dry weight of the cells, the dry weight of the polymer, the dry weight ratio of the polymer to the cells, and the amount (mol %) of the 3-hydroxy-3-hydroxy-5-{[(4-methylphenyl)methyl]sulfanyl)valerate (abbreviated as “3HMBzyTV” in the resulting polymer in Examples 16-18.
TABLE 6
Cell Dry
Polymer Dry
3HMBzyTV
Weight
Weight
Polymer Weight/
Unit
(mg/L)
(mg/L)
Cell Weight (%)
mol %
Example 16
805
481
59.8
41.0
Example 17
625
408
65.3
56.2
Example 18
710
377
53.1
38.8
Example 19
Pseudomonas cichorii YN2 was inoculated to 200 mL of M9 medium containing 0.5% of polypeptone (Wako Pure Chemical Industries, Ltd.) and 0.1% of 5-{[(4-fluorophenyl)methyl]sulfanyl}valeric acid, and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized. The weight of the lyophilized cells was weighed (dry weight of the cells).
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The sole precipitate was recovered and dried in vacuum to yield 106 mg of polyhydroxyalkanoate.
The average molecular weight of the resulting PHA was determined by gel permeation chromatography (GPC; TOSOH HLC-8220, column; TOSOH TSK-GEL SuperHM-H, solvent; chloroform, polystyrene equivalent). As a result, the number average molecular weight Mn was 32,000 and the weight average molecular weight Mw was 96,000.
In order to identify the structure of the PHA obtained, the PHA was subjected to NMR analysis under the following conditions.
Spectrometer
FT-NMR: Bruker DPX 400 with spectrometer frequencies of 400 MHz for 1 H-NMR and 100 MHz for 13 C-NMR.
Conditions
Nuclear Species: 1 H, 13 C Solvent: CDCl 3
Temperature: room temperature
FIG. 4 shows measured 1 H-NMR spectra. Identification results thereof are given in Table 7 below. FIG. 5 shows measured 13 C-NMR spectra. Identification results thereof are given in Table 8 below.
TABLE 7
Chemical
Splitting
shifts (ppm)
Integration
patterns
Identification
1.83
2 H
qurt
d1
2.35-2.58
4 H
m
b1, e1
3.64
2 H
s
f1
5.20
1 H
m
c1
6.92-6.98
2 H
m
j1, k1
7.23-7.26
2 H
m
h1, l1
TABLE 8
Chemical shifts
(ppm)
Identification
26.7
d1
33.2
e1
35.3
f1
38.6
b1
69.7
c1
115.1 & 115.4
i1, k1
130.3 & 130.3
h1, l1
133.7
g1
160.6 & 163.0
i1
168.9
a1
From the results shown in the Tables 7 and 8, the PHA comprises a monomer unit of 3-hydroxy-5-{[(4-fluorophenyl)methyl]sulfanyl}valerate, and other monomer units of 3-hydroxyalkanoates and/or 3-hydroxyalkenoates having 4 to 12 carbon atoms such as 3-hydroxybutyric acid and 3-hydroxyvaleric acid. More specifically, the PHA has a structure represented by the following chemical formula (19):
The integration of the 1 H-NMR spectra indicated that the resulting PHA contains 76.7 mol % of 3-hydroxy-5-{[(4-fluorophenyl)methyl]sulfanyl}valerate monomer unit.
Example 20
Pseudomonas cichorii YN2 was inoculated to 200 mL of M9 medium that contains 0.1% of nonanoic acid and 0.1% of 5-{[(4-fluorophenyl)methyl]sulfanyl}valeric acid and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized. The weight of the lyophilized cells was weighed (dry weight of the cells).
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 89 mg of polyhydroxyalkanoate.
The PHA obtained was subjected to NMR analysis and average molecular weight determination under the conditions as in Example 19. From the results of the NMR analysis, it was revealed that the PHA in this example comprises a monomer unit of 3-hydroxy-5-{[(4-fluorophenyl)methyl]sulfanyl}valerate and other monomer units of 3-hydroxyalkanoates and/or 3-hydroxyalkenoates having 4 to 12 carbon atoms such as 3-hydroxybutyrate and 3-hydroxyvalerate to confirm that it has a constitution represented by the chemical formula (19). The integration of the 1 H-NMR spectra indicated that the PHA of this example contains 27.0 mol % of 3-hydroxy-5-{[(4-fluorophenyl)methyl]sulfanyl}valerate monomer unit.
Example 21
Pseudomonas cichorii YN2 was inoculated to 200 mL of M9 medium containing 0.5% of yeast extract (DIFCO) and 0.1% of 5-{[(4-fluorophenyl)methyl]sulfanyl}valeric acid, and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized. The weight of the lyophilized cells was weighed (dry weight of the cells).
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 69 mg of polyhydroxyalkanoate in this Example.
The PHA obtained was subjected to NMR analysis and average molecular weight determination under the conditions as set forth in the Example 19. From the results of the NMR analysis, it was revealed that the PHA in this example comprises a monomer unit of 3-hydroxy-5-{[(4-fluorophenyl)methyl]sulfanyl}valerate and other monomer units of 3-hydroxyalkanoates and/or 3-hydroxyalkenoates having 4 to 12 carbon atoms such as 3-hydroxybutyrate and 3-hydroxyvalerate to confirm that it has a constitution represented by the above chemical formula (19). The integration of the 1 H-NMR spectra indicated that the PHA of this example contains 76.7 mol % of 3-hydroxy-5-{[(4-fluorophenyl)methyl]sulfanyl}valerate monomer unit.
Example 22
Pseudomonas cichorii YN2 was inoculated to 200 mL of M9 medium containing 0.5% of sodium glutamate and 0.1% of 5-{[(4-fluorophenyl)methyl]sulfanyl}valeric acid, and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized. The weight of the lyophilized cells was weighed (dry weight of the cells).
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield. 68 mg of polyhydroxyalkanoate in this Example.
The PHA obtained was subjected to NMR analysis and average molecular weight determination under the same conditions as set forth in Example 19. From the results of the NMR analysis, it was revealed that the PHA in this example comprises a monomer unit of 3-hydroxy-5-{[(4-fluorophenyl)methyl]sulfanyl}valerate and other monomer units of 3-hydroxyalkanoates and/or 3-hydroxyalkenoates having 4 to 12 carbon atoms, such as 3-hydroxybutyrate and 3-hydroxyvalerate, confirming that it has a constitution represented by the chemical formula (19). The integration of the 3 H-NMR spectra indicated that the PHA of this example contains 90.3 mol % of 3-hydroxy-5-{[(4-fluorophenyl)methyl]sulfanyl}valerate monomer unit.
Example 23
Pseudomonas cichorii YN2 was inoculated to 200 mL of M9 medium containing 0.5% of D-glucose and 0.1% of 5-{[(4-fluorophenyl)methyl]sulfanyl}valeric acid, and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, re-suspended in 200 mL of M9 medium containing 0.5% of D-glucose and 0.1% of 5-([(4-fluorophenyl)methyl]sulfanyl}valeric acid but no nitrogen source (NH 4 Cl), and cultured at 30° C. with shaking at 125 strokes/min for 48 hours. After that, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized. The weight of the lyophilized cells was weighed (dry weight of the cells).
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 164 mg of polyhydroxyalkanoate.
The PHA obtained was subjected to NMR analysis, and the average molecular weight determination under the conditions as set forth in Example 19. The results of the NMR analysis show that the PHA in this example comprises a monomer unit of 3-hydroxy-5-{[(4-fluorophenyl)methyl]sulfanyl}valerate and other monomer units of 3-hydroxyalkanoates and/or 3-hydroxyalkenoates having 4 to 12 carbon atoms, such as 3-hydroxybutyrate and 3-hydroxyvalerate to confirm that it has a constitution represented by the chemical formula (19). The integration of the 1 H-NMR spectra indicated that the PHA of this example contains 85.9 mol % of 3-hydroxy-5-{[(4-fluorophenyl)methyl]sulfanyl}valerate monomer unit.
Example 24
Pseudomonas cichorii H45 was inoculated to 200 mL of M9 medium containing 0.5% of D-glucose and 0.1% of 5-{[(4-fluorophenyl)methyl]sulfanyl}valeric acid and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, re-suspended in 200 mL of M9 medium containing 0.5% of D-glucose and 0.1% of 5-{[(4-fluorophenyl)methyl]sulfanyl}valeric acid but no nitrogen source (NH 4 Cl), and cultured at 30° C. with shaking at 125 strokes/min for 48 hours. After that, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized. The weight of the lyophilized cells was weighed (dry weight of the cells).
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 138 mg of polyhydroxyalkanoate.
The PHA obtained was subjected to NMR analysis, and the average molecular weight determination under the conditions as set forth in Example 19. The results of the NMR analysis show that the PHA in this example comprises a monomer unit of 3-hydroxy-5-{[(4-fluorophenyl)methyl]sulfanyl}valerate and other monomer units of 3-hydroxyalkanoates and/or 3-hydroxyalkenoates having 4 to 12 carbon atoms, such as 3-hydroxybutyrate and 3-hydroxyvalerate to confirm that it has a constitution represented by the chemical formula (19). The integration of the 1 H-NMR spectra indicated that the PHA of this example contains 90.7 mol % of 3-hydroxy-5-{[(4-fluorophenyl)methyl]sulfanyl}valerate monomer unit.
Example 25
Pseudomonas jessenii P161 was inoculated to 200 mL of M9 medium containing 0.5% of D-glucose and 0.1% of 5-{[(4-fluorophenyl)methyl]sulfanyl}valeric acid, and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, re-suspended in 200 mL of M9 medium containing 0.5% of D-glucose and 0.1% of 5-{[(4-fluorophenyl)methyl]sulfanyl}valeric acid but no nitrogen source (NH 4 Cl), and cultured at 30° C. with shaking at 125 strokes/min for 48 hours. After that, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized. The weight of the lyophilized cells was weighed (the cell dry weight).
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 138 mg of polyhydroxyalkanoate.
The PHA obtained was subjected to NMR analysis, and the average molecular weight determination under the conditions as set forth in Example 19. The results of the NMR analysis show that the PHA in this example comprises a monomer unit of 3-hydroxy-5-{[(4-fluorophenyl)methyl]sulfanyl}valerate and other monomer units of 3-hydroxyalkanoates and/or 3-hydroxyalkenoates having 4 to 12 carbon atoms, such as 3-hydroxybutyrate or 3-hydroxyvalerate to confirm that it has a constitution represented by the chemical formula (19). The integration of the 1 H-NMR spectra indicated that the PHA of this example contains 88.5 mol % of 3-hydroxy-5-{[(4-fluorophenyl)methyl]sulfanyl}valerate monomer unit.
Example 26
Pseudomonas cichorii YN2 was inoculated to 200 mL of M9 medium containing 0.5% of polypeptone (Wako Pure Chemical Industries, Ltd.) and 0.1% of 5-{[(4-fluorophenyl)methyl]sulfanyl}valeric acid and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, re-suspended in 200 mL of M9 medium containing 0.5% of sodium pyruvate and 0.1% of 5-{[(4-fluorophenyl)methyl]sulfanyl}valeric acid but no nitrogen source (NH 4 Cl), and cultured at 30° C. with shaking at 125 strokes/min for 48 hours. After that, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized. The weight of the lyophilized cells was weighed (the cell dry weight).
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 125 mg of polyhydroxyalkanoate.
The PHA obtained was subjected to NMR analysis, and the average molecular weight determination under the conditions as set forth in Example 19. The results of the NMR analysis show that the PHA in this example comprises a monomer unit of 3-hydroxy-5-{[(4-fluorophenyl)methyl]sulfanyl}valerate and other monomer units of 3-hydroxyalkanoates and/or 3-hydroxyalkenoates having 4 to 12 carbon atoms, such as 3-hydroxybutyrate or 3-hydroxyvalerate to confirm that it has a constitution represented by the chemical formula (19). The integration of the 1 H-NMR spectra indicated that the PHA of this example contains 89.5 mol % of 3-hydroxy-5-{[(4-fluorophenyl)methyl]sulfanyl}valerate monomer unit.
Example 27
Pseudomonas cichorii H45 was inoculated to 200 mL of M9 medium containing 0.5% of polypeptone (Wako Pure Chemical Industries, Ltd.) and 0.1% of 5-{[(4-fluorophenyl)methyl]sulfanyl}valeric acid and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, re-suspended in 200 mL of M9 medium containing 0.5% of sodium pyruvate and 0.1% of 5-{[(4-fluorophenyl)methyl]sulfanyl}valeric acid but no nitrogen source (NH 4 Cl), and cultured at 30° C. with shaking at 125 strokes/min for 48 hours. After that, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized. The weight of the lyophilized cells was weighed (the cell dry weight).
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 154 mg of polyhydroxyalkanoate.
The PHA obtained was subjected to NMR analysis, and the average molecular weight determination under the conditions as set forth in Example 19. The results of the NMR analysis show that the PHA in this example comprises a monomer unit of 3-hydroxy-5-{[(4-fluorophenyl)methyl]sulfanyl}valerate and other monomer units of 3-hydroxyalkanoates and/or 3-hydroxyalkenoates having 4 to 12 carbon atoms, such as 3-hydroxybutyrate or 3-hydroxyvalerate to confirm that it has a constitution represented by the chemical formula (19). The integration of the 1 H-NMR spectra indicated that the PHA of this example contains 97.9 mol % of 3-hydroxy-5-{[(4-fluorophenyl)methyl]sulfanyl}valerate monomer unit.
Example 28
Pseudomonas jessenii P161 was inoculated to 200 mL of M9 medium containing 0.5% of polypeptone (Wako Pure Chemical Industries, Ltd.) and 0.1% of 5-{[(4-fluorophenyl)methyl]sulfanyl}valeric acid and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, re-suspended in 200 mL of M9 medium containing 0.5% of sodium pyruvate and 0.1% of 5-{[(4-fluorophenyl)methyl]sulfanyl}valeric acid but no nitrogen source (NH 4 Cl), and cultured at 30° C. with shaking at 125 strokes/min for 48 hours. After that, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized. The weight of the lyophilized cells was weighed (the cell dry weight).
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 158 mg of polyhydroxyalkanoate.
The PHA obtained was subjected to NMR analysis, and the average molecular weight determination under the conditions as set forth in Example 19. The results of the NMR analysis show that the PHA in this example comprises a monomer unit of 3-hydroxy-5-{[(4-fluorophenyl)methyl]sulfanyl}valerate and other monomer units of 3-hydroxyalkanoates and/or 3-hydroxyalkenoates having 4 to 12 carbon atoms, such as 3-hydroxybutyrate or 3-hydroxyvalerate to confirm that it has a constitution represented by the chemical formula (19). The integration of the 1 H-NMR spectra indicated that the PHA of this example contains 91.6 mol % of 3-hydroxy-5-{[(4-fluorophenyl)methyl]sulfanyl}valerate monomer unit.
Table 9 shows the dry weight of the cells, the dry weight of the polymer, the dry weight ratio of the polymer to the cells, and the amount in mol % of the 3-hydroxy-5-{[(4-fluorophenyl)methyl]sulfanyl}valerate unit (abbreviated as “3HFBzyTV”) in the resulting PHA polymer in Examples 19 to 28.
TABLE 9
Cell Dry
Polymer Dry
3HFBzyTV
Weight
Weight
Polymer Weight/
Unit
(mg/L)
(mg/L)
Cell Weight (%)
mol %
Example 19
945
530
56.1
76.7
Example 20
680
445
65.4
27.0
Example 21
915
345
37.7
76.7
Example 22
740
340
45.9
90.3
Example 23
1120
820
73.2
85.9
Example 24
940
690
73.4
90.7
Example 25
955
690
72.3
88.5
Example 26
1015
625
61.6
89.5
Example 27
1125
770
68.4
97.9
Example 28
1215
790
65.0
91.6
Process for Producing Polyhydroxyalkanoate Comprising 3-Hydroxy-4-{[(4-Fluorophenyl)Methyl]Sulfanyl}Butyric Acid Monomer Unit
Example 29
Pseudomonas cichorii YN2 was inoculated to 200 mL of M9 medium containing 0.5% of yeast extract (DIFCO) and 0.1% of 4-{[(4-fluorophenyl)methyl]sulfanyl}butyric acid, and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized. The weight of the lyophilized cells was weighed (dry weight of the cells).
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 41 mg of polyhydroxyalkanoate.
The average molecular weight of the resulting PHA was determined by gel permeation chromatography (GPC; TOSOH HLC-8220, column; TOSOH TSK-GEL SuperHM-H, solvent; chloroform, polystyrene equivalent). As a result, the number average molecular weight Mn was 15,300 and the weight average molecular weight Mw was 37,100.
In order to identify the structure of the PHA obtained, the PRA was subjected to NMR analysis under the following conditions.
Spectrometer
FT-NMR: Bruker DPX 400 with spectrometer frequencies of 400 MHz for 1 H-NMR.
Conditions
Nuclear Species: 1 H
Solvent: CDCl 3
Reference: TMS/CDCl 3 in capillary
Temperature: room temperature
FIG. 6 shows measured 1 H-NMR spectra. Identification results thereof are given in Table 10 below.
TABLE 10
Chemical
Splitting
shifts (ppm)
Integration
patterns
Identification
2.40-2.72
4 H
m
b1, d1
3.65
2 H
m
e1
5.27
1 H
m
c1
6.95
2 H
m
h1, j1
7.23
2 H
m
g1, k1
From the results shown in the Table 10, the subject PHA comprises a monomer unit of 3-hydroxy-4-{[(4-fluorophenyl)methyl]sulfanyl}butyrate and other monomer units of 3-hydroxyalkanoates and/or 3-hydroxyalkenoates having 4 to 12 carbon atoms, such as 3-hydroxybutyrate or 3-hydroxyvalerate. More specifically, the PHA has a structure represented by the following chemical formula (20).
The integration of the 1 H-NMR spectra indicated that the resulting PHA contains 89.8 mol % of 3-hydroxy-4-{(4-fluorophenyl)methyl]sulfanyl}butyrate monomer unit.
Example 30
Pseudomonas cichorii YN2 was inoculated to 200 mL of M9 medium containing 0.1% of nonanoic acid and 0.1% of 4-{[(4-fluorophenyl)methyl]sulfanyl}butyric acid and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then the cells were collected by centrifugation, washed once with cold methanol, and lyophilized and weighed to determine dried cell weight.
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 45 mg of polyhydroxyalkanoate.
The PHA obtained was subjected to NMR analysis, and the average molecular weight determination under the conditions as set forth in Example 29. The results of the NMR analysis show that the PHA in this example comprises a monomer unit of 3-hydroxy-4-{[(4-fluorophenyl)methyl]sulfanyl}butyrate and other monomer units of 3-hydroxyalkanoates and/or 3-hydroxyalkenoates having 4 to 12 carbon atoms, such as 3-hydroxybutyrate or 3-hydroxyvalerate to confirm that it has a constitution represented by the chemical formula (20). The integration of the 1 H-NMR spectra indicated that the PHA of this example contains 10.6 mol % of 3-hydroxy-4-{[(4-fluorophenyl)methyl]sulfanyl}butyrate monomer unit.
Example 31
Pseudomonas cichorii YN2 was inoculated to 200 mL of M9 medium containing 0.5% of sodium glutamate and 0.1% of 4-{[(4-fluorophenyl)methyl]sulfanyl}butyric acid and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, washed once with cold methanol, lyophilized and weighed.
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 11 mg of polyhydroxyalkanoate.
The PHA obtained was subjected to NMR analysis, and the average molecular weight determination under the conditions as set forth in Example 29. The results of the NMR analysis show that the PHA in this example comprises a monomer unit of 3-hydroxy-4-{[(4-fluorophenyl)methyl]sulfanyl}butyrate and other monomer units of 3-hydroxyalkanoates and/or 3-hydroxyalkenoates having 4 to 12 carbon atoms, such as 3-hydroxybutyrate or 3-hydroxyvalerate to confirm that it has a constitution represented by the chemical formula (20). The integration of the 1 H-NMR spectra indicated that the PHA of this example contains 84.1 mol % of 3-hydroxy-4-{[(4-fluorophenyl)methyl]sulfanyl}butyrate monomer unit.
Example 32
Pseudomonas cichorii YN2 was inoculated to 200 mL of M9 medium containing 0.5% of D-glucose and 0.1% of 4-{[(4-fluorophenyl)methyl]sulfanyl}butyric acid and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, re-suspended in 200 mL of M9 medium containing 0.5% of D-glucose and 0.1% of 4-{[[4-fluoromethyl]phenyl]methyl}sulfanyl]butyric acid but no nitrogen source (NH 4 Cl), and cultured at 30° C. with shaking at 125 strokes/min for 48 hours. After that, the cells were collected by centrifugation, washed once with cold methanol, lyophilized and weighed as the dry cell weight.
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 153 mg of polyhydroxyalkanoate.
The PHA obtained was subjected to NMR analysis, and the average molecular weight determination under the conditions as set forth in Example 29. The results of the NMR analysis show that the PHA in this example comprises a monomer unit of 3-hydroxy-4-{[(4-fluorophenyl)methyl]sulfanyl}butyrate and other monomer units of 3-hydroxyalkanoates and/or 3-hydroxyalkenoates having 4 to 12 carbon atoms, such as 3-hydroxybutyrate or 3-hydroxyvalerate to confirm that it has a constitution represented by the chemical formula (20). The integration of the 1 H-NMR spectra indicated that the PHA of this example contains 68.5 mol % of 3-hydroxy-4-{[(4-fluorophenyl)methyl]sulfanyl}butyrate monomer unit.
Example 33
Pseudomonas cichorii H45 was inoculated to 200 mL of M9 medium containing 0.5% of polypeptone (Wako Pure Chemical Industries, Ltd.) and 0.1% of 4-{[(4-fluorophenyl)methyl]sulfanyl}butyric acid, and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, re-suspended in 200 mL of M9 medium containing 0.5% of sodium pyruvate and 0.1% of 4-{[(4-fluorophenyl)methyl]sulfanyl}butyric acid but no nitrogen source (NH 4 Cl), and cultured at 30° C. with shaking at 125 strokes/min for 48 hours. After that, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized. The weight of the lyophilized cells was weighed (the cell dry weight).
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 38 mg of polyhydroxyalkanoate.
The PHA obtained was subjected to NMR analysis, and the average molecular weight determination under the conditions as set forth in Example 29. The results of the NMR analysis show that the PHA in this example comprises a monomer unit of 3-hydroxy-4-{[(4-fluorophenyl)methyl]sulfanyl}butyrate and other monomer units of 3-hydroxyalkanoates and/or 3-hydroxyalkenoates having 4 to 12 carbon atoms, such as 3-hydroxybutyrate or 3-hydroxyvalerate to confirm that it has a constitution represented by the chemical formula (20). The integration of the 1 H-NMR spectra indicated that the PHA of this example contains 43.1 mol % of 3-hydroxy-4-{[(4-fluorophenyl)methyl]sulfanyl}butyrate monomer unit.
Example 34
Pseudomonas jessenii P161 was inoculated to 200 mL of M9 medium containing 0.5% of D-glucose and 0.1% of 4-{[(4-fluorophenyl)methyl]sulfanyl}butyric acid, and cultured with shaking at 125 strokes/min at 30° C. for 48 hours. Then, the cells were collected by centrifugation, re-suspended in 200 mL of M9 medium containing 0.5% of D-glucose and 0.1% of 4-{[(4-fluorophenyl)methyl]sulfanyl}butyric acid but no nitrogen source (NH 4 Cl), and cultured at 30° C. with shaking at 125 strokes/min for 48 hours. After that, the cells were collected by centrifugation, washed once with cold methanol, and lyophilized. The weight of the lyophilized cells was weighed (the cell dry weight).
The lyophilized pellet was suspended in 20 mL of chloroform and stirred at 60° C. for 20 hours to extract polyhydroxyalkanoate. The extract was filtered through a membrane filter of a pore size of 0.45 μm and concentrated by a rotary evaporator. The concentrated solution was precipitated with cold methanol. The precipitate was recovered and dried in vacuum to yield 47 mg of polyhydroxyalkanoate.
The PHA obtained was subjected to NMR analysis, and the average molecular weight determination under the conditions as set forth in Example 29. The results of the NMR analysis show that the PHA in this example comprises a monomer unit of 3-hydroxy-4-{[(4-fluorophenyl)methyl]sulfanyl}butyrate and other monomer units of 3-hydroxyalkanoates and/or 3-hydroxyalkenoates having 4 to 12 carbon atoms, such as 3-hydroxybutyrate or 3-hydroxyvalerate to confirm that it has a constitution represented by the chemical formula (20). The integration of the 1 H-NMR spectra indicated that the PHA of this example contains 48.7 mol % of 3-hydroxy-4-{[(4-fluorophenyl)methyl]sulfanyl}butyrate monomer unit.
Table 11 shows the dry weight of the cells, the dry weight of the polymer, the dry weight ratio of the polymer to the cells, and the amount in mol % of 3-hydroxy-4-{[(4-fluorophenyl)methyl]sulfanyl}butyrate unit (abbreviated as “3HFBzyTB”) in the resulting PHA polymer in Examples 29 to 34.
TABLE 11
Cell Dry
Polymer Dry
3HFBzyTB
Weight
Weight
Polymer Weight/
Unit
(mg/L)
(mg/L)
Cell Weight (%)
mol %
Example 29
975
205
21.0
89.8
Example 30
515
225
43.7
10.6
Example 31
955
55
5.8
84.1
Example 32
1365
765
56.0
68.5
Example 33
515
190
30.1
43.1
Example 34
780
235
36.9
48.7 | A polyhydroxyalkanoate that comprises a unit represented by the following chemical formula (1):
wherein R1 is a substituent of an aromatic ring selected from the group consisting of H, CH 3 , C 2 H 5 , CH 3 CH 2 CH 2 , (CH 3 ) 2 CH, (CH 3 ) 3 C, a halogen atom, CN, NO 2 , COOR′, and SO 2 R″, wherein R′ is selected from the group consisting of H, Na, K, CH 3 , and C 2 H 5 , and R″ is selected from the group consisting of OH, a halogen atom, ONa, OK, OCH 3 , and OC 2 H 5 ; and x represents an integer of 1 to 8 being the same or different each other in the polyhydroxyalkanoate. A method for producing the polyhydroxyalkanoate is also provided. | 2 |
RELATED APPLICATIONS
The present application is related to U.S. Provisional Patent Application, Ser. No. 60/721,172, filed Sep. 27, 2005, which is incorporated herein by reference and to which priority is claimed pursuant to 35 USC 119.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to the field of micromachined glass components and methods of manufacture of the same.
2. Description of the Prior Art
In addition to consumer glass products, glass-blowing is often used to create confinement chambers for different types of gases. A normal glass-blowing process is (roughly) as follows:
Heat the glass to its softening point Remove glass from the heat source (e.g. flame) Immediately apply pressure (blowing) to shape the glass Repeat all steps if needed
In the past, micro-spheres have been fabricated using polymer droplets that are allowed to fall through a high column whose temperature profile is controlled by independent heating units, allowing for expansion of the spheres. See R. Cook, “Creating Microsphere Targets for Inertial Confinement Fusion Experiments”, Energy & Technology Review, pp. 1-9, April 1995; and R. Dagani, “Microspheres Play Role in Medical, Sensor, Energy, Space Technologies”, Chemical and Engineering News, pp. 33-35, December 1994
However, all of these prior efforts have dealt with the fabrication of spheres that are not attached to any surface and can only be filled with specific gases during the fabrication process. Small confinement chambers can be achieved by etching (using dry or wet etchant) glass, silicon, or other materials. However, etching usually leads to rough surfaces as well as very thick sidewalls making it unfit for many applications (e.g. when optics need to be integrated with the chamber). Furthermore, it is not possible to achieve a spherical shape with traditional etching techniques. Large-scale confinement chambers have been created in the past using traditional glass-blowing techniques. However, conventional glass-blowing can only be used to create large components (not micro-fabrication compatible).
What is need is a method and apparatus where glass-blowing is performed in a parallel batch process on a microscopic level.
BRIEF SUMMARY OF THE INVENTION
The method of the illustrated embodiment allows for microfabrication compatible micro-glass-spheres, integrated on a substrate, wafer or chip. These spheres can be filled by gases or other substances post fabrication. In the illustrated embodiment of the invention, the spheres are attached to a wafer, allowing for integration with conventional micro-fabrication components and allowing for batch-fabrication of micro-glass components.
The invention includes a method for shaping glass on a microscopic scale to mass-produce multiple glass components, i.e. shaped simultaneously on a micro-scale. This is accomplished by bonding a thin sheet of glass to a perforated wafer, heating the glass, and then blowing the glass from the reverse side of the wafer. One potential application of this invention is as a confinement chamber for various gases. The chambers are much smaller than traditional glass-blown chambers and are micro-fabrication compatible.
The invention can be used as a microscopic gas confinement chamber. Many applications of this can be considered, e.g. nuclear magnetic resonance gyroscopes, micro-lamps, and hydrogen capsules for H-vehicles. Other possible applications include laser fusion targets, as well as lab-on-a-chip, medication capsules, and other biomedical devices.
More specifically, the illustrated embodiment of the invention is a method for glass-blowing on a microscopic level comprising the steps of defining holes through a substrate, such as a semiconductor or silicon substrate, wafer or chip, and disposing a sheet of thermally formable material, such as glass, onto the substrate covering the holes. The sheet of thermally formable material is heated, such as by a flame, until a predetermined degree of plasticity is achieved. It must be understood that many other forms of heating are contemplated within the scope of the invention, which are both localized to at least some extent to the thermally formable material, such as by a laser, or may be global, such as in an oven or heating chamber. Fluidic pressure is applied through the holes to the sheet of thermally formable material, while the sheet of glass is still plastic. Microspheres are formed or blown on the substrate in the sheet of thermally formable material by means of continued application of pressure for a predetermined time.
Preferably the holes are defined by etching using a deep-reactive ion etching (DRIE) method. The step of disposing a sheet of thermally formable material comprises bonding the thermally formable material to the substrate using anodic bonding. Again many other different kinds methods of bonding now known or later devised could be substituted for anodic bonding. In the illustrated embodiment the step of disposing a sheet of thermally formable material comprises bonding borosilicate glass to the substrate. The step of defining holes through the substrate comprises etching a plurality of holes through the substrate and forming microspheres on the substrate results in simultaneously batch fabricating the microspheres.
The illustrated embodiment of the method further comprises the step of fabricating integrated electrical and mechanical components on or into the substrate, wafer or chip using conventional microfabrication methods as are now known or as may be later devised as substitutes therefor.
In one embodiment the method further comprises the step of providing an assembly to sandwich the thermally formable material between two flanges. The assembly comprises a plurality of metal flanges with gaskets in between, screws or any other equivalent means for providing a tight seal between the flanges and the substrate, a valve, and a hose connected to the valve to allow for the blowing of the thermally formable material. The blowing of the microspheres is either manually performed or a pressure regulated gas tube is used with the assembly.
In another embodiment the method further comprises selectively heating of gases or other substances enclosed in the microspheres using a resistive heater integrated on the substrate.
In still another embodiment the method further comprises the step of disposing a gas-source material in a solid state in the microspheres and heating the gas-source material to produce a vapor inside the microspheres.
In one embodiment the method further comprises the step of reducing magnetic fields introduced by the resistive heater by using two very thin resistive layers in the heater in which the current flows in opposite directions, where the resistive layers are spaced apart by an insulating dielectric layer.
In still another embodiment the method further comprises the step of protecting portions of the thermally formable material that do not cover any holes with a layer of a material with a very high melting point to function as a heat shield during blowing and heating.
In the illustrated embodiment the resistive heater is made from a material that has a high melting temperature, and the method further comprises the step of protecting portions of the thermally formable material using the resistive heater as the heat-shield to reduce the risk of undesired deformation of selected areas of the thermally formable material when heated above its softening point.
In an embodiment the method further comprises the step of protecting portions of the thermally formable material comprises using a protective heat-shield separate from the heater.
The invention is also characterized as an apparatus comprising a substrate, wafer or chip having a plurality of holes defined therethrough, a layer or sheet of thermally formable material or glass disposed onto the substrate, wafer or chip covering the plurality of holes, and a plurality of microspheres thermally formed in the layer or sheet by means of applied pressure through the plurality of holes when the thermally formable material or glass has been heated to a predetermined degree of plasticity.
In a further embodiment the apparatus further comprises a selected gas, gases or other substances filling the plurality of microspheres as supplied through the plurality of holes.
In a further embodiment the plurality of holes are sealed from the back once the microspheres have been filled with gases or other substances. The seal is preferably created by using an adhesive or by anodically bonding a glass wafer to the back of the silicon wafer. Many other sealing methods now known or later devised could be equivalently substituted.
In other embodiments the apparatus further comprises an integrated electrical resistive heater disposed on the layer in thermal proximity to the plurality of microspheres.
In an illustrated embodiment the apparatus further comprises a heat shield selectively disposed on the substrate to shield selected portion of the substrate from heat applied to the microspheres.
In the illustrated embodiment the integrated electrical resistive heater is comprised of at least one high temperature resistant layer and functions as a heat shield selectively disposed on the substrate to shield selected portions of the substrate from heat applied to the microspheres.
It must also be understood that the apparatus in other embodiments further comprises at least one micromechanical or microelectrical device integrated into or onto the substrate.
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 USC 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 of the definition provided by the claims under the judicial doctrine of equivalents, and in the case where the claims are expressly formulated under 35 USC 112 are to be accorded full statutory equivalents under 35 USC 112. The invention can be better visualized by turning now to the following drawings wherein like elements are referenced by like numerals.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 a - 1 f are cross sectional diagrams illustrating a first embodiment of the method of the invention.
FIG. 2 is a perspective view of a glass covered substrate, wafer or chip on which a plurality of glass microspheres have been formed.
FIG. 3 is an exploded view of an assembly which is used in one embodiment to hold the substrate, wafer or chips during fabrication of the microspheres in a batch fabrication process.
FIGS. 4 a - 4 f are cross sectional diagrams illustrating another embodiment of the method of the invention in which a resistive heater/heat shield is used to heat gas in the microspheres and to selectively protect portions of the substrate, wafer or chips from heat applied to the microspheres and the glass layer from which they are formed.
The invention 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 invention defined in the claims. It is expressly understood that the invention as defined by the claims may be broader than the illustrated embodiments described below.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The illustrated embodiments of the invention was developed as a microscopic gas confinement chamber, but many other applications are expressly considered as within the scope of the invention, e.g. vapor cells for nuclear magnetic resonance gyroscopes, micro-lamps, and hydrogen capsules for H-vehicles. Other applications include laser fusion targets, as well as lab-on-a-chip, medication capsules, and other biomedical devices. This listing by no means exhausts the list of potential uses and applications of the invention.
FIGS. 1 a - 1 f depict the illustrated embodiment fabrication process. In FIG. 1 a a photoresist layer 12 is disposed on a substrate 10 and patterned to define a plurality of openings 14 defined in photoresist layer 12 . Cylindrical holes 16 are then etched in FIG. 1 b all the way through a silicon substrate 10 , preferably using deep-reactive ion etching (DRIE). The photoresist layer 12 is removed from the top of the perforated substrate 10 as shown in FIG. 1 c . A thin sheet of glass 18 (e.g. Pyrex 7740) is then bonded as shown in FIG. 1 d to on top of the substrate 10 (e.g. using anodic bonding), covering all of the etched holes 16 . Glass sheet 18 is preferably 50 to 500 μm thick. In the illustrated embodiment a 100 μm thick glass sheet 18 was used. It must be expressly understood that the thickness of the sheet 18 is a matter of design chosen according to the teachings of the invention and are not to be understood as limited by the examples given in the illustrated embodiment. Heat (e.g. a flame) is applied from the top side to heat the glass 18 above its softening point. The source of heat is then removed and fluidic or pneumatic pressure is immediately applied from the bottom of the substrate 10 . Small, approximately spherical bubbles or microspheres 20 in glass sheet 18 will now form on top of the substrate 10 . The size and thickness of microspheres 20 can be selective controlled by the choice of the diameter and shape of the etched holes 16 , the thickness of the glass sheet 18 , and the time and pressure allowed for pneumatic expansion in the step of FIG. 1 e.
In the step of FIG. 1 f a sealing layer 21 can be disposed on the bottom of substrate 10 sealing holes 16 to trap and maintain the gases or other materials that may have been injected or disposed into holes 16 and microspheres 20 . The composition of layer 21 may be structured according to the needs of the application, including providing a selectively gas permeable or impermeable layer as might be required by the application.
As shown in FIG. 2 multiple microspheres 20 can be batch fabricated simultaneously. The fabrication process also allows for potential integration of other electrical and mechanical components which may also fabricated on the substrate 10 using conventional microfabrication techniques.
One assembly 22 that can be used to assist in the blowing of the microspheres 20 is illustrated in exploded view in FIG. 3 . This assembly 22 can be characterized as a pressure chamber that can be used to sandwich the perforated, glass-covered substrate 10 , 18 between two flanges 24 a and 24 b . The assembly 22 is comprised of a number of metal flanges 24 a - 24 d with gaskets 26 in between. Screw-holes 28 are provided in flanges 24 a - 24 d to allow for a tight connection and seal between the flanges 24 a - 24 d and the glass covered substrate 10 , 18 . A hose (not shown) is connected to the valved flange 24 d on top to allow for the actual blowing of the glass microspheres 20 . The blowing is done either manually or using a pressure regulated gas tube (not shown).
FIGS. 4 a - 4 f show a modified fabrication process. In this embodiment the steps are the same as in the case of FIGS. 1 a - 1 f above, but in addition a resistive heater 34 is integrated on the substrate 10 at FIG. 4 d , allowing for post-fabrication heating of the enclosed gases or other substances in microspheres 20 if needed. For example, materials that are in a solid state can be heated to achieve a vapor inside the microspheres 20 . In order to reduce the magnetic fields introduced by the resistive heater 34 , two very thin resistive layers 30 a and 30 b are used in which the current flows in opposite directions. The resistive layers 30 a and 30 b are spaced by an insulating dielectric 32 . The actual shape of the resistive heater 34 is arbitrary, but preferentially it is a spiral that encircles an individual glass microsphere 20 . The step in FIG. 4 f includes the disposition of a sealing layer 21 on the bottom of substrate 10 in the same manner as described above in connection with FIG. 1 f.
The glass sheet 18 needs to be heated above its softening point (e.g. by a flame) in order to be able to form the microspheres 20 . However, due to the small size of the microspheres 20 , localized heating is very hard to achieve. Instead, the whole substrate 10 will be heated simultaneously. Thus, areas that are supposed to stay bonded to the substrate 10 and not be affected by the glass-blowing will also be heated. In order to protect the parts of the glass sheet 18 that does not cover any holes 16 , a layer of a material with a very high melting point can be deposited on top of the glass sheet 18 . Many different materials may be used for this purpose, e.g. silicon dioxide, silicon nitride, or indium tin oxide (ITO), which is only a partial list of substitute materials. This material will function as a heat shield during the glass-blowing.
If the resistive heater 34 is made from a material that has a high melting temperature, e.g. ITO, this same layer or layers in heater 34 can also function as the heat-shield 36 to reduce the risk of undesired deformation of certain areas of the glass when it is heated to its softening point. Alternatively, separate independent layers are used for the heater 34 and the protective heat-shield 36 .
In summary the illustrated embodiment encompasses within its scope a method of manufacture and the product made from the method as it relates to:
Glass-blowing on a microscopic level Glass-blowing compatible with microfabrication technologies Wafer-level glass-blowing Method for fabricating microspheres Simultaneous manufacturing of numerous microspheres on a chip or wafer
Many alterations and modifications may be made by those having ordinary skill in the art without departing from the spirit and scope of the invention. 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 invention as defined by the following invention and its various 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 invention 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 invention 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 invention is explicitly contemplated as within the scope of the invention.
The words used in this specification to describe the invention and its 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.
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.
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.
The claims are thus to be understood to include what is specifically illustrated and described above, what is conceptionally equivalent, what can be obviously substituted and also what essentially incorporates the essential idea of the invention. | A method for forming microspheres on a microscopic level comprises the steps of defining holes through a substrate, disposing a sheet of thermally formable material onto the substrate covering the holes, heating the sheet of thermally formable material until a predetermined degree of plasticity is achieved, applying fluidic pressure through the holes to the sheet of thermally formable material, while the sheet of glass is still plastic, and forming microspheres on the substrate in the sheet of thermally formable material by means of continued application of pressure for a predetermined time. The invention also includes a substrate having a plurality of holes defined therethrough, a layer of thermally formable material disposed onto the substrate covering the plurality of holes, and a plurality of microspheres thermally formed in the layer by means of applied pressure through the holes when it has been heated to a predetermined degree of plasticity. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to fiber optics, including fiber optics used in Fiber Channel interconnections and other interconnections.
2. Description of the Background Art
Optical fibers are used in various systems. For example, Fiber Channel systems use optical fibers. The Fiber Channel standard was developed and adopted by the American National Standard for Information Systems (ANSI). Briefly, Fiber Channel is a switched protocol that allows concurrent communication among servers, workstations, and various peripherals.
FIG. 1 depicts a block diagram of a representative Fiber Channel architecture. A Fiber Channel network 100 is presented. Systems such as a workstation 120 and servers 122 are interconnected with various subsystems (for example, a tape subsystem 126 , a disk subsystem 128 , and a display subsystem 130 ) via a Fiber Channel fabric 110 .
The Fiber Channel fabric 110 is a system that interconnects various node ports (N_ports) attached to the fabric 110 . The fabric 110 receives frames of data from a source node port and, using a Fiber Channel protocol, route the frames to a destination node port. In a preferred embodiment, the first protocol is the Fiber Channel protocol. Similar protocols, such as the a synchronous transfer mode (ATM), may be used in other similar embodiments.
Each of the various systems (for example, server 122 ) and subsystems (for example, disk subsystem 128 ) connected to the Fiber Channel fabric 110 includes an associated node port 140 . Each node port comprises a hardware communication device at the node end of a link.
The fabric ports (F_ports) 142 are access points of the fabric 110 for physically connecting the various node ports 140 . The fabric 110 has the capability of routing data frames based upon information contained within the frames as specified by a class of service. The node port 140 typically manages the point-to-point connection between itself and the fabric 110 .
Interconnections between the node ports 140 and fabric ports 142 typically include fiber optic cables. As the use of fiber optics has grown in Fiber Channel systems and other systems, a need for fiber management techniques has arisen.
It is desirable to improve the management of fiber optics used in Fiber Channel systems and in other systems.
SUMMARY
One embodiment of the invention pertains to a manufactured multi-fiber cable for optical systems. The multi-fiber cable is manufactured to include a plurality of individual fiber cables, each individual fiber cable including a single optical fiber surrounded by a protective covering. There is a main cable hose around the individual fiber cables, and there is a connector on each end of each individual fiber cable. The individual fiber cables in the multi-fiber cable are preconfigured to be visually distinct from each other.
Another embodiment pertains to a manufactured multi-fiber cable for Fiber Channel systems that includes a plurality of individual fiber cables, a main cable hose around the individual fiber cables, a protective reinforcement along the main cable hose, a connector on each end of each individual fiber cable, labels that are thermally attached to each end of the individual fiber cables during manufacture of the multi-fiber cable, and labels that are thermally attached to each end of the main cable hose during manufacture of the multi-fiber cable. Distinctive colors are used on the coverings of the individual fiber cables so as to provide said visual distinctness between the individual fiber cables of the multi-fiber cable. The individual fiber cables each comprise a single optical fiber surrounded by a covering, and the individual fiber cables extend outward past the main cable hose by less than one meter. Each connector comprises a precision ceramic ferrule.
Another embodiment of the invention pertains to a Fiber Channel system. The system comprises a fiber channel fabric, including a plurality of fabric ports, and a plurality of node systems, each node system including a node port. The system further comprises a multi-fiber. The multi-fiber cable includes individual fiber cables. Each individual fiber cable connects a node port to a fabric port.
Other embodiments of the invention are also disclosed.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts a block diagram of a representative Fiber Channel architecture.
FIG. 2 is a schematic diagram illustrating a multi-fiber cable for efficient manageability in accordance with an embodiment of the invention.
FIG. 3 is a schematic diagram illustrating a multi-fiber cable for efficient manageability with a protective reinforcement in accordance with an embodiment of the invention.
FIG. 4 is a schematic diagram illustrating a multi-fiber cable for efficient manageability with protective reinforcement and a spare fiber cable in accordance with an embodiment of the invention.
DETAILED DESCRIPTION
Disadvantages and Difficulties with Conventional Techniques
The management of optical fibers presents concerns than were not faced in conventional copper wire systems. For example, consider the management of the multitude of single optical fibers in a typical Fiber Channel system.
A first concern is that optical fibers require significantly greater care than do copper wires, as they cannot be bent sharply, crimped, or twisted. Since optical fibers and their assemblies tend to be expensive, it is desirable to avoid damage to the optical fibers during system installation and maintenance.
A second concern is that determining or verifying identification of individual optical fibers is considerably more difficult than for copper wires. With copper wires, the correspondence between wires at the ends of a long cable may be readily verified, for example, by shorting two wires at one end and checking for connectivity at the other end, or by using inexpensive testing devices. On the other hand, verifying the correspondence between optical fibers at the ends of an optical cable require more complex and expensive test equipment.
For example, today in data centers, numerous single fiber cables are typically used between a server and a Fiber Channel switch (or storage array). A typical set-up may require 100 to 350 single fiber cables. These cables need to be laid very carefully into a raised floor or in overhead trays. During the lay process, the cables are vulnerable to be damaged. In addition, the ends of the individual fiber cables conventionally require laborious manual identification and manual labeling. Debugging errors due to incorrect connections are painstaking.
Solutions Provided by the Present Disclosure
The present disclosure provides solutions to the above-discussed problems. By using the multi-fiber cable configured as disclosed herein, labor to lay the fiber cables is minimized. Hence, higher quality work is achievable at a faster rate when laying the fiber cables.
Specific Embodiments
In accordance with an embodiment of the invention, a multi-fiber (multi-string) Fiber Channel cable is disclosed. The multi-fiber Fiber Channel cable may be implemented with two, four, six, eight, or sixteen individual fiber cables per multi-fiber cable. The multiple individual fiber cables are tied together and configured together within a hose to form the multi-fiber cable.
FIG. 2 is a schematic diagram illustrating a multi-fiber cable 200 for efficient manageability in accordance with an embodiment of the invention. The particular cable depicted in FIG. 2 is a four-fiber cable. However, as mentioned above, other multi-fiber cables implemented in accordance with an embodiment of the invention may include other numbers of fibers, such two, four, six, eight, or sixteen individual fiber cables per multi-fiber cable.
The multi-fiber cables are preferably formed in standard lengths. For example, the standard lengths may be two meters, five meters, ten meters, fifteen meters, thirty meters, and one hundred meters. Other standard lengths are possible.
The ends of each individual fiber cable 202 of the multi-fiber cable 200 are configured to extend outside the hose (or wrap or coat) 206 of the main multi-fiber cable 200 . Each end of an individual fiber cable 202 is further pre-configured with a connector 204 . In a preferred embodiment, the connector 204 is a precision ceramic ferrule, such as an LC connector or an SC connector.
Each individual fiber cable 202 is preferably coated with a protective coating of a unique color and/or pattern. In other words, each individual fiber cable 202 in the multi-fiber cable is individually identifiable by the color and/or the pattern of its outer coating.
In a preferred embodiment, the multi-fiber cable 200 may be constructed with a main label 208 on each end. In addition, each individual (independent) cable 202 may also be constructed with an individual fiber label 210 . The labels may be attached, for example, using a thermal transfer process, and the attachment may be performed using an automated label applicator machine.
FIG. 3 is a schematic diagram illustrating a multi-fiber cable 300 for efficient manageability with a protective reinforcement in accordance with an embodiment of the invention. The embodiment shown in FIG. 3 is again a 4-fiber cable, but other embodiments would have other numbers of individual cables.
The difference between the multi-fiber cable 300 in FIG. 3 and the multi-fiber cable 200 in FIG. 2 is that an additional protective reinforcement is added. As illustrated, the protective reinforcement may comprise, for example, a metal spiral 302 . The metal spiral 302 is depicted as implemented on the outside of the main cable hose 206 , but may also be implemented on the inside or embedded within the main cable hose 206 .
Advantageously, the protective reinforcement further prevents damage from external forces. For example, the metal spiral 302 may prevent damage from a person stepping on the cable 300 with his or her foot. As another example, the metal spiral 302 may prevent damage from a person strongly bending the cable 300 by limiting the amount of bend inflicted on the cable 300 .
FIG. 4 is a schematic diagram illustrating a multi-fiber cable 400 for efficient manageability with protective reinforcement and a spare fiber cable 402 in accordance with an embodiment of the invention. The embodiment shown in FIG. 4 is again a 4-fiber cable, but other embodiments would be designed for other numbers of individual cables.
The difference between the multi-fiber cable 400 in FIG. 4 and the multi-fiber cable 300 in FIG. 3 is that the spare (redundant) fiber cable 402 is added. The spare fiber cable 402 may be conveniently used to make a connection in case one of the other cables (or one of the connectors) has a fault or breaks. The spare cable 402 may also be used if need for an additional connection arises.
Advantages
The present application discloses a multi-fiber cable for efficient manageability of Fiber Channel or other systems. There are various advantages of using the multi-fiber cable as disclosed herein.
First, compared with the conventional technique of laying hundreds of individual cable fibers, using the multi-fiber cables substantially reduces the number of (main) cables to lay. This advantageously reduces labor time required.
Second, using the multi-fiber cables substantially reduces risk of damage to the individual fiber cables. The bundle of individual fiber cables is difficult to bend at a sharp angle, and the main cable hose further protects the individual cable fibers from damage.
Third, the multi-fiber cables (after being laid) are easier to remove. The bundling of the individual fiber cables reduces the number of cables to remove and also reduces the chance of damage to the individual fiber cables. The main cable hose provides an additional protection for the fragile individual fiber cables.
Fourth, the labor required to label the cables is reduced due to the built-in labels. In one embodiment, as depicted in FIG. 2 , labels are built-in both on each end of the main cable hose and on each end of the individual fiber cables.
Fifth, trouble shooting is simplified and facilitated using the multi-fiber cable as disclosed herein. The coloring of the individual fiber cables makes it easier to distinguish and identify each independent fiber. In addition, the built-in labeling may be used to further distinguish and identify each main cable and each independent fiber therein.
In the above description, numerous specific details are given to provide a thorough understanding of embodiments of the invention. However, the above description of illustrated embodiments of the invention is not intended to be exhaustive or to limit the invention to the precise forms disclosed. One skilled in the relevant art will recognize that the invention can be practiced without one or more of the specific details, or with other methods, components, etc. In other instances, well-known structures or operations are not shown or described in detail to avoid obscuring aspects of the invention. While specific embodiments of, and examples for, the invention are described herein for illustrative purposes, various equivalent modifications are possible within the scope of the invention, as those skilled in the relevant art will recognize.
These modifications can be made to the invention in light of the above detailed description. The terms used in the following claims should not be construed to limit the invention to the specific embodiments disclosed in the specification and the claims. Rather, the scope of the invention is to be determined by the following claims, which are to be construed in accordance with established doctrines of claim interpretation. | One embodiment disclosed relates to a manufactured multi-fiber cable for optical systems. The multi-fiber cable is manufactured to include a plurality of individual fiber cables, each individual fiber cable including a single optical fiber surrounded by a protective covering. There is a main cable hose around the individual fiber cables, and there is a connector on each end of each individual fiber cable. The individual fiber cables in the multi-fiber cable are preconfigured to be visually distinct from each other. Other embodiments are also disclosed. | 6 |
This is a division of application Ser. No. 319,238, filed Nov. 9, 1981, which is a continuation of application Ser. No. 761,290, filed Jan. 21, 1977, now U.S. Pat. No. 4,375,414, which is a continuation of application Ser. No. 255,154, filed May 19, 1972, abandoned.
BACKGROUND OF THE INVENTION
This invention relates to improved immunoassays of psychotomimetic drugs, narcotic drugs, tetrahydrocannabinols and other psychoactive drugs.
At the present time, there are certain methods used for the determination of psychotomimetic and narcotic drugs in biological materials.
The techniques that are used in the present time for the determination of drugs in biological materials, are described in detail in the Handbook of Analytical Toxicology (Irving Sunshine, Editor; The Chemical Rubber Company, Publisher; Cleveland, OH, 1969). They include in different combination for the different drugs: paper, thin layer and gas-liquid chromatographic methods, crystal tests, fluorescence, infrared, ultraviolet, thermal microscopy and animal pharmacology studies.
In general, the tests are time consuming, expensive, require expensive equipment, and require well trained personnel. Some of the tests are not sensitive, others lack high specificity. Special difficulty is encountered in the determination of one drug in the presence of other drugs in the same biological material specimen. Thus heroin is difficult to determine in the urine in the presence of nicotine, as disclosed by D.J. Berry et al in "The Detection of Drugs of Dependence in Urine" (Bulletin on Narcotics 22, No. 3, July-September 1970; United Nations Publication). Tetrahydrocannabinols are difficult to determine in the presence of barbiturates, and complicated methods are needed for their determination in the presence of barbiturates, as described by Harold V. Street in "Identification of Drugs by a Combination of Gas-Liquid, Paper and Thin-Layer Chromatography" (Journal of Chromatography 48, 291-4, 1970).
The methods of the present invention have the advantages of simplicity, speed, specificity and low cost. They also have the advantage of being able to be applied "on the spot" (e.g. emergency room of a small field hospital). Van Vunakis et al ("Production and Specificity of Antibodies Directed towards 3,4,5-Trimethoxy-phenyl-ethylamine, and 2,5-Dimethoxy-4-methylamphetamine," Bioch. Pharmacol. 18, 393-404, 1969) were able to obtain high specificity and sensitivity in their determination, by microcomplement fixation inhibition of 3,4,5-Trimethoxy-phenylethylamine and congeners, as well as 2,5-Dimethoxy-4-Methylamphetamine and congeners. Micro-complement-fixation-inhibition is however a complicated method. Reagents have to be prepared freshly for each experiment, and they require specially trained personnel. In the methods hereinafter to be described, no such limitations are present.
The length of time required by presently known procedures for determining psychoactive drugs also severely limits their usefulness in clinical applications.
The invention also includes immunological methods for the treatment of drug intoxication; the treatment and prevention of drug addiction, drug dependence and drug abuse; and the treatment of schizophrenia. The need for treatment methods for intoxication by psychoactive drugs, methods for freeing persons dependent on such drugs from their dependence, and methods of treating schizophrenia has long been felt. The present methods provide attractive and useful approaches to all of these needs.
SUMMARY OF THE INVENTION
In accordance with this invention, generally stated, diagnostic and treatment methods are provided by the use of the haptenic properties of psychoactive material. The term "psychoactive" includes psychotomimetic compounds containing an indol ring such as N,N-Dimethyltryptamine and its congeners and LSD 25 and its congeners; amphetamines and their congeners; narcotics such as phenanthrene alkaloids (such as morphine, heroin, codeine, hydromorphone, and levorphenol) and nonphenanthrene alkaloids (such as meperidine, methadone, and phenazocine); and tetrahydrocannabinols and other cannabinoids.
A hapten may be defined as any small molecule which by itself does not produce antiboides but which, when conjugated to a carrier protein or other macro-molecular carrier, induces in the recipient animal or human the production of antibodies which are specific to the small molecule.
The present invention is based in part upon the application of known immunoassay techniques for haptens to certain psychoactive compounds wihch have not heretofore been recognized as haptens (such as N,N-dimethyltryptamine and congeners, and tetrahydrocannabinols and their congeners); in part upon the discovery of methods of adapting techniques which were heretofore used only for the determination of antibodies or complete antigens to techniques for determining haptens; in part upon the discovery of immunological treatment methods for such seemingly disparate medical problems as drug intoxication, drug dependence and schizophrenia; and in part upon the development of entirely new methods for the treatment of drug intoxication based in part upon the haptenic characteristics of the intoxicating drugs.
The discovery that 5-methoxy-N,N-dimethyltryptamine and congeners are haptens and the recognition that tetrahydrocannabinols (such as delta-9-tetrahydrocannabinol) are haptens, permits their determination by known immunoassay methods for haptens, such as radioimmunoassay (Spector et al, Science 168, page 1347, 1970; Niswender et al, in Immunological Methods in Steriod Determination, edited by Peron and Caldwell, 1970, pages 149-173) and micro-complement fixation inhibition (Levine, in Handbook of Experimental Immunology, edited by D.M. Weir, 1967, pages 707-719, especially page 712). These psychoactive haptens also may be utilized in the determination of their antibodies by methods such as those described in Handbook of Experimental Immunology (ed. Weir), pages 423-968, for example hemagglutination (W.J. Herbert "Passive Hemagglutination" in Handbook of Experimental Immunology, pages 720-744).
The invention also encompasses the determination of haptens, and particularly psychoactive haptens, by simple and accurate agglutination and agglutination-inhibition assays.
The agglutination inhibition assay includes the steps of mixing a sample containing an unknown quantity of psychoactive hapten with a predetermined quantity of an antibody to the hapten, and then combining this mixture with a predetermined quantity of the hapten bound to an agglutinable particulate carrier. Presence of a sufficient amount of the psychoactive hapten in the sample will inhibit hemagglutination. The usual tray or other equipment may be utilized to obtain a quantitive measure of the psychoactive hapten (Handbook of Experimental Immunology, pp 782-785).
The agglutination methods involve the binding of an antibody to an agglutinable particulate carrier. This binding may require the use of a chemical binding technique such as the bis-disazotized-benzidine (BDB) technique. These techniques are set out in Handbook of Experimental Immunology, pages 737-740, Cua-Lim et al, J. Allergy 34, 142 (1963); Ingraham, Proc. Soc. Exp. Biol., N.Y. volume 99, 452 (1958).
These agglutinable carrier-bound antibodies may be used in a number of agglutination procedures. In one, a sample is mixed with the agglutinable carrier-bound antibody in suspension, the agglutinable carrier-antibody is then mixed with a free antibody to the hapten. If the sample contains above a minimal amount of the free hapten, agglutination will result. In another method antibodies to two different sites on the hapten are prepared and bound to an agglutinable particulate carrier. Addition of a sample which contains the free hapten produces agglutination. Other procedures utilizing two different antibodies to two different sites on the hapten may be provided in which only one, or neither, of the antibodies is bound to an agglutinable particulate carrier.
In all of the agglutination and agglutination inhibition procedures, erythrocytes (red blood cells) are the presently preferred carrier. The erythrocyte may or may not be treated, for example by formalin treatment (Ingraham, supra). However, other agglutinable material such as latex or other particles may be useful in some or all of the methods.
The invention also encompasses the passive immunization for drug (hapten) intoxication. it is particularly directed to in vitro immunotherapy methods through immuno-dialysis or immuno-adsorbtion techniques. It also may be applied to auto-intoxication by substances etiological to diseases such as schizophrenia. For example, recent research indicates that N,N-diemthylatedindoleamine are psychotomimetic agents which are etiological to schizophrenia. See for example Tanimukai et al in Recent Advances in Biological Psychiatry, volume 10, pages 6-15 (1968); Narasimhachari et al in Biological Psychiatry volume 3, pages 21-23 (1971). Therefore, one treatment method includes the passive immunization of schizophrenic patients with antibodies to N,N-dimethylatedindoleamine. The treatment of species which are etiological to schizophrenia and also are complete antigens may include the step of splitting the antibodies (for example by the method set out in Boyd, Fundamentals of Immunology (4th edition, 1966), especially at pages 70-71 in order to prevent precipitation of the species. The active immunization procedure may be used both in schizophrenia, by administration of an antigen which produces antibodies to a species which is etiological to schizophrenia (for example a protein conjugate of N,N-dimethyltryptamine), or in the treatment of drug dependent persons. The treatment includes administration of an antigen (or antigens) which produces antibodies to the drug (or drugs) on which the individual is dependent.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following examples are illustrative of the methods and materials of this invention.
The following methods are utilized to produce the materials needed to carry out the invention:
a. Conjugation
The psychoactive haptens which contain an immino (NH) group (such as the N,N-dimethylated indolamines and LSD) are conjugated to Human Serum Albumin (HSA) using the Mannich formaldehyde reaction, as described by Ranadive and Sehon, Canad. J. Biochem, 45, p 1701 (1967). The conjugation in this method is to the immino (NH) group. Other haptenmacromolecular conjugates are formed by standard methods, for example those set out in Spector, in Advances in Biochemical Psychopharmacology, volume 1 (ed. Costa and Greengard) p 181 (1969); Pinckard et al in Handbook of Experimental Immunology, p 493; and Goodfriend et al in Immunologic Methods in Steroid Determination, p 15; and Ingraham, supra.
Determination of conjugation is done following the method described in Strahilevitz et al, Biological Psychiatry 3, 227 (1971), by a spectrofluorometric method.
b. Production of Antibodies to Haptens
Immunizations of rabbits with conjugates in complete Freund's Adjuvant are carried out by a similar procedure to the one described by Strahilevitz et al, supra. The preparation of antisera and globulin fractions are also described in this reference. The antibodies may be purified by known methods such as those set out in Immunologic Methods in Steroid Determination.
c. Preparation of Erythrocytes (Agglutinable Particulate Carrier)
Preparation of formalinized, type O human ertyhrocytes is done according to the methods described by Ingraham, supra. Some cells prepared by this method can be used even 15 months after preparation.
d. Binding of Haptens ot Erythorcytes
Conjugation of haptens to the formalinized erthyrocytes is done by the Bis-Diazotized-Benzidine technique (BDB technique).
Determination of presence of antibodies in the rabbit serum and determination of their specificity and cross reactivity in the serum of the drug-HSA-conjugate immunized rabbits is done by hemagglutination of the drug bound erthrocytes by their specific antisera and by specific inhibition of the hemagglutination in the presence of the free drug (hapten inhibition in the presence of the free drug) (see Fultrope et al. Brit. Med. J., Apr. 20, 1963, pp 1049-54). The hemagglutination procedure is shown diagrammatically in FIG. 1. For example, inhibition of hemagglutination by NNDMT but not by other drugs will indicate presence of antibody specific to NNDMT. Determination of presence of specific antibodies is also done by double diffusion and double diffusion inhibition studies (i.e. inhibition of the precipitation in the presence of the free drug as described by Ranadive and Sehon, supra, for Serotonin).
EXAMPLE 1
Radioimmunoasay of Tetrahydrocannabinols
A tetrahydrocannabinol is conjugated to a protein by one of the standard methods utilized to bind steroids to proteins (Immunologic Methods in Steroid Determination). The conjugate is prepared in such a way as to produce a ratio of tetrahydrocannabinol to carrier molecule of from 4:1 to 30:1. The conjugate is emulsified in a phosphate buffer saline (pH 7.4). Rabbits, sheep or other suitable animals are immunized with from about 1/2-2 mg of the conjugate per kilogram body weight (in concentration of about 5 mg/ml PGS) in equal volume mixture with complete Freund's adjuvant. The mixture is again emulsified before injection into multiple sites, e.g. intradermally, into the foot pad, subcutaneously, and intraperitoneally. Injections are made once every two weeks and blood taken from the animal, allowed to clot, and tested for antibodies, as set out in Ranadive and Sehon, supra.
Radioactively labeled ( 3 H) tetrahydrocannabinol (obtained from National Institute of Mental Health) in a predetermined amount, is added to the antibody to the tetrahydrocannabinol. Ammonium sulfate (or another precipitating reagent) is then added in order to precipitate the tetrahydrocannabinol-bound antibody. The precipitate is sedimented by centrifugation and washed. The precipitate is then dissolved with a suitable solubilitizing reagent (such as Tween 80 or NCS solubilitizer [Amersham/Searle]). A standard curve is prepared by adding to the test solution varying amounts of unlabeld tetrahydrocannabinol to the predetermined amount of labeled tetrahydrocannabinol. The quantity of tetrahydrocannabinol in a sample is then determined by addition of the sample (e.g. serum) together with the predetermined quantity of labeled tetrahydrocannabinol and antibody. Comparison of the radioactivity count of the precipitate with the standard curve yields the amount of tetrahydrocannabinol in the sample.
EXAMPLE 2
Radioimmunoassay of 5-methoxy-N,N-dimethyltryptamine
Antibodies to 5-methoxy-N,N-dimethyltryptamine (5-MeO-N-DMT) are prepared according to the method of Strahilevitz et al, supra. 5-MeO-N-DMT is conjugated to a radioactive ( 131 I) protein. Radioimmunoassays are carried out using the radioactive hapten-protein conjugate, in the same manner as in EXAMPLE 1.
In EXAMPLES 1 and 2 radioimmunoassay can be modified by using the "double antibody procedure" as described by Niswender et al in Immunological Methods in Steroids Determination, p 149. In EXAMPLE 1, non-labeled tetrahydrocannabinol may be conjugated to 131 I-rabbit serum albumin, or to another radioactive labeled protein carrier for the purpose of being used in the radioimmunoassay procedure instead of the radioactive 3 H tetrahydrocannabinol.
EXAMPLE 3
Detection of a Specific Psychoactive Drug by a Qualitative Test
By titration, a suitable amount of antiserum specific to a drug and red cells to which this drug is conjugated, is determined. As shown in FIG. 2, tubes 20 made of plastic with a thin plastic divider 21 are used for this test system. If the drug in question is present in the sample that is being examined, as a free hapten, it will combine to the antibodies against it after the sample is introduced into the upper compartment of the tube and incubated for 15 minutes at 37° C. When, after incubation as described above, the thin plastic barrier 21 in the middle of the tube 20, is broken by the needle with which the sample was put into the upper compartment 22, and the mixture of serum sample tested and the drug specific antiserum is allowed to mix with the drug-conjugated erythrocytes in the lower compartment of the tube, the presence of at least a particular quantity of the drug (or a particular range of quantities) will inhibit or prevent agglutination of the drug-conjugated erthyrocytes. Thus agglutination inhibition will be an indication of the presence of free drug in the sample tested. (If the drug is carried in the serum, on a macromolecule like protein, or another macromolecular carrier, then it will be a complete antigen and precipitation may occur while the drug is incubating in the upper compartment 22 of the tube with the specific antiserum. However, hemagglutination inhibition should in addition be demonstrated in the lower compartment 23 of the tube).
EXAMPLE 4
Quantitive Determination of Drugs
This is done with a tray similar to the one that is used routinely for microhemagglutination studies (see Tyrell, supra).
Serial dilutions of the tested serum is added to the upper compartment by a small syringe. The difference between the tray used for this test and the one that is being used routinely, is that the tray with the cylinders will be higher, and that each cylinder has an upper and a lower compartment divided by a thin plastic divider (as shown schematically in FIG. 2). The procedure is otherwise identical with the one previously described in EXAMPLE 3. The drug "titer" is the highest dilution in which hemagglutination will be inhibited.
Quantitive determination may also be done by the use of routinely used trays and loops used for microhemagglutination and microhemagglutination inhibition.
This method can be used for the determination of a wide variety of psychoactive haptens, including the N,N-dimethylated indolamines, LSD, narcotics (like heroin or morphine) and tetrahydrocannabinols, and may in principle be applied to determining any haptenic chemical or normal or pathological haptenic body metabolite.
In the above described quantitive methods, with each unknown serum sample that will be tested for the presence of drugs, a known control negative sample, and a known positive sample, that will include a known amount of drug, will be done simultaneously.
EXAMPLE 5
Qualitative Determination of Drug-Hapten by
Reversed BDB Technique
Presence of Drug-Hapten in this system will be detected by hemagglutination.
As shown in FIG. 2A, tubes 20 are the same as for EXAMPLE 3. Antibody to the drug-hapten is prepared in an identical way as described in EXAMPLES 3 and 4. The anti drug-hapten antibodies are conjugated to the formalinized erythrocytes as described by Cua-Lim et al, supra, in the Reversed BDB technique. They are then placed in the upper compartment 22 of the tube. Free antibodies to the drug-hapten are included in the lower compartment 23 of the tube 20. The material tested for free drug-hapten is then injected into the upper compartment 22 and incubated. If free drug-hapten is present it will be bound to the anti-drug-hapten-antibodies which are conjugated to the erythrocytes. After the incubation, the tube is centrifuged and the red cells in the upper compartment are washed with Phosphate Buffer Saline PH 7.4 (PBS). The thin plastic divider 21 is then pierced by the needle and the material drops into the lower compartment 23. If drug-hapten is present attached to the anti-drug-hapten-antibodies that are conjugated to the erythrocytes, then hemagglutination appears indicating presence of free drug in the sample.
This is shown schematically in FIG. 3.
The method has the advantage of indicating the presence of hapten by hemagglutination rather than by hemagglutination-inhibition.
EXAMPLE 6
Quantitiative Determination of Drug-Hapten by Reversed BDB Technique
The same technique described in EXAMPLE 5, is utilized for quantitiative determination of drug-hapten, utilizing the tray and the other methods as described in EXAMPLE 4. Here again the presence of free drug-hapten is indicated by hemagglutination.
Addition of material containing free hapten to the upper compartment 22 and then incubated causes the hapten-drug to bind to the formalinized erythrocyte bound antibody, and in the presence of unbound anti drug-hapten antibody, agglutination will take place in the lower compartment 23.
The foregoing methods (EXAMPLES 3-6) can be adapted for use in non-animal materials such as plant materials and drug samples, as can the following two EXAMPLES.
EXAMPLE 7
Qualitative Determination for the Presence of One Drug out of a Group of Drugs
This method utilizes a test system similar to the test system described in EXAMPLE 5. The system is identical with the exception that in the upper compartment 22, a mixture of several batches of formalinized erythrocytes is present, each batch being conjugated with an antibody to a different drug-hapten.
Similarly the lower compartment 23 contains a mixture of unbound antibodies, identical with those present in the upper compartment 22. If the antibodies, present in a free form in the lower compartment 23 and conjugated to the erythrocytes in the upper compartment 22, are specific against drugs: A, B, C, D, E... and if any one of these drugs or some of these drugs is present in the tested sample, a positive reaction, indicated by a hemagglutination, will be visible in the lower compartment 23 thus indicating that one or more of the drugs A, B, C, D, E... are present in the sample.
A detailed analysis for specific drugs as described above will determine the specific drug or drugs which are present in the tested sample.
EXAMPLE 8
Production and Use of Antibodies to Different Sites on a Hapten
In the foregoing EXAMPLE, in order to ensure that the hapten will have at least two combining sites to combine with the antibodies, the hapten can be conjugated to the carrier protein (or another macromolecular carrier) through two different sites in the hapten molecule. For example, with estrone, conjugation will be done to rings A and D respectively in the estrone molecule by the methods described by Goodfriend and Sehon in Immunological Methods in Steroid Determination, supra. Conjugation to two different sites in the hapten with protein, can be done in various haptens by a variety of conjugation methods. The two conjugates of the hapten (in the example the protein conjugates of Estrone through ring A and D respectively) will be used for immunization of animals (such as rabbits). (Immunization with each of the conjugates is preferably done in different rabbits.) It is expected that the immunized rabbit will produce antibodies directed towards an antigenic site on the estrone or other hapten molecule which is sterically guided by the site on the molecule through which conjugation to the protein was done. Generally the antibody will be directed toward a site away from (complementary to) the comjugated protein. Besides using different conjugation methods, other methods by which usefully different antibodies to the same hapten may be produced include the use of antibodies to the conjugate of the hapten with two different carriers, like HSA (human serum albumin) and hemocyanin or other two different carriers. Either the same method of conjugation or different methods of conjugation can be used for conjugating the hapten to the two different carriers. Each one of the two antisera may then be specific against another antigenic site on the hapten molecule. The same result may be obtained or enhanced by actively immunizing different animal species (such as sheep and rabbits) with the hapten-protein conjugate or conjugates to produce the first and second antibodies.
The antibodies to two hapten sites may be used in a number of procedures, as follows:
a. Both antibodies are conjugated to red blood cells (RBC) or other agglutinable-particulate carrier like latex and placed in suspension, as in the preceding example, in a container. As shown in FIG. 4, in the presence of free hapten in the test material (e.g., free estrone) an antigenic site on the ring A of the estrone will attach itself to the antibody produced against the protein conjugate which was conjugated with estrone through ring D. Similarly, an antigenic site on ring D of estrone will attach itself to the antibody produced against the protein conjugate which was conjugated with estrone through ring A. Therefore, the presence of at least a certain amount (i.e. a certain range) of hapten in a sample will produce agglutination.
b. As shown in FIG. 5, with the use of anti A and anti D antibodies in the test system estrone can be demonstrated by precipitation in fluid or solid media. Other haptens as well can be determined by precipitation in the presence of antibodies to two different antigenic sites in the hapten.
c. Other procedures may use combinations of antibodies which are bound to agglutinable particles and antibodies which are not so bound. Also, more than two different antibodies may be used.
All of the foregoing hemagglutination tests can be used in the presence of developing agents such as polyvinylpyrolidone (P.V.P.) or Dextran in order to increase their sensitivity. (Handbook of Experimental Immunology, p. 995).
EXAMPLE 9
Active Immunization Treatment of Schizophrenia
Active immunization treatment of schizophrenia is carried out with a conjugate of a psychotomimetic compound (or a combination of conjugates of such compounds) such as N,N-diemthyltryptamine, 5-methoxy-N,N-dimethyltryptamine, tryptamine, and other psychotomimetic haptens, the presence of which has been described in the biological materials of schizophrenic individuals. These psychotomimetic small molecules are conjugated with protein macromolecular carrier, or with polyamine acid molecules as carriers (like: polylysine or polyarginine).
Immunization of the patient is carried out either without the use of adjuvant or with the use of an adjuvant. This will be tried in humans only after the safety of the compound, safety of the route of immunization, schedule of immunization, and the safety of the adjuvant used if any, has been extensively studied, and determined in studies in experimental animals, by suitable methodology which is available at the present time.
Treatment of schizophrenia by active immunization with complete antigens (immunogens) that may be etiological in the disease (either protein or other complete antigens (immunogens)) will include immunization with enzymes that may be etiological in schizophrenia like: indoleamine N methyl transferase, indoleamine O methyl transferase, catechol amine N methyl transferase, catechol amine O methyl transferase as well as other enzymes that may be related to the etiology of schizophrenia.
EXAMPLE 10
Treatment of Schizophrenia by a Passive Immunotherapy Method
Immunization of the patient is carried out by administering antibodies to species which are etiological to the disease. For example, in acute schizophrenia, antibodies to 5-methoxy-N,N-dimethyltryptamine may be administered.
In passive immunization treatment with antibodies against complete antigens present in schizophrenia serum, in order to avoid possible precipitation of the complete antigens by the antibodies, the anitbodies may be treated in such a way as to make them "univalent", for example by mild reduction with dilute HCl and breaking of the antibody molecule into two identical halfs each with one combining site (William C. Boyd, Fundamentals of Immunology 4th edition, Interscience Publishers New York, London, Sidney, 1966 pp 70,71). Other methods for obtaining "univalent" non-precipitating antibody, that can yet bind the antigen and possibly neutralize it are also summarized in this reference and can be utilized.
EXAMPLE 11
Treatment of Drug Dependence by Active Immunization
The immunization of drug dependent individuals is in principle similar to the immunotherapy of schizophrenia by active immunization with protein conjugates of methylated indoleamines. The drug or drugs on which the individual is dependent are conjugated to a protein or other macromolecular carrier, for example by one of the methods discussed hereinabove. After the individual is withdrawn from the drug (for example by methadone withdrawl, for heroin), he will be immunized by administration of the conjugate, in a manner similar to that used for the active immunization treatment of schizophrenia.
Many conditions require the removal of species from the blood of an individual under circumstances which make active immunization and even passive immunization treatments (as well as other treatment methods) impractical. Examples of such conditions are severe intoxication (such as with phenothiazines) and certain acute schizophrenic conditions (such as acute catatonic stupor). In addition, methods are needed for removal, from the circulation of a patient having a malignant tumor, of certain antibodies against tumor-specific antigens. These specific antibodies are known to be "enhancing antibodies" (which stimulate the growth of the tumor). Removal of these antibodies may be therapeutic for such patients. The removal of antibodies which may be etiological in certain allergic conditions or autoimmune diseases is expected to be therapeutic for these conditions. These antibodies include the antibodies specific to the septal region of the brain, e.g. "Taraxein", which according to findings of Heath et al (Am. J. Psychiat., 124, p 1019, (1968); Arch Gen. Psychiat., 16, p 1 (1967)) are etiological in schizophrenia. It also may be desirable to remove from the circulation of schizophrenic patients other proteins such as the alpha-2 globulin which was found by Frohman et al (Ann. N.Y. Acad. Sci., 96 p 438 (1962)) in schizophrenic patients and which may be etiological in schizophrenia. In all of these conditions, one or both of the following two EXAMPLES may provide an effective treatment.
EXAMPLE 12
Immunodialysis Treatment Primarily for Drug Intoxication
This system is particularly well adapted for the removal of haptens from the circulatory system. All of the apparatus, compartments therein and the materials used with it are of course sterile. In brief, as shown in FIG. 6, a column 25 is divided into a first compartment 29 and a second compartment 32 by a semipermeable membrane 33. Such membranes, having various pore sizes, and thus which are permeable to molecules of various sizes are commercially available. The first compartment 29, an inlet 30 for a catheter 30a which is to be connected to an artery 30b of the patient 30c to be detoxified or otherwise treated, and an outlet 31 connected to a catheter 31a which is to be connected to a vein 31b of the patient, 30c together comprise a blood flow passage through the column 25. The second compartment 32 includes the heterologous antibody directed against the hapten which is to be removed. The antibody is contained in an isotonic solution or other solution such as those used in conventional dialysis treatment ("artificial kidney"). If the hapten is not known, (as in a patient suffering from an overdose of an unknown psychoactive drug), the solution in the second compartment 32 may include a mixture of antibodies to drugs which may be implicated. The semipermeable membrane is folded or pleated so that the surface area of interaction between the patient's blood and the antibody to the drug in the compartment 32 will be as great as possible. The semipermeable membrane is chosen to be of such a porosity and permeability as to be permeable to small molecules like the intoxicating hapten of interest, but it not permeable to large molecules present in the blood of the patient such as serum proteins.
Because the antibodies specifically bind drug molecules that diffuse from the blood of the patient in compartment 29 to compartment 32 through the semipermeable membrane 33, a continuous gradient is present for this intoxicating drug in the patient's blood that therefore continues to diffuse from compartment 29 to compartment 32 as long as compartment 32 includes antibodies directed against the intoxicating drug which are free to bind molecules of the intoxicating drug.
The dialysis system, thus far described, has great advantages over simple blood dialysis, in that it is more specific, and, because of the high speed of binding of free hapten by the antibody to it, the system will generally require a smaller apparatus, and the time for detoxification will be much shorter than required by the use of simple dialysis ("artificial kidney"). The chance of saving the patient's life will therefore be increased. It may also be possible to use vein to vein catheterization of the patient rather than arterial catheterization because detoxification will be accomplished faster.
When the dialysis system thus far described has been used until the antibody is exhausted for practical use, the solution of the antibody-bound hapten may be removed through a drain 38, and fresh antibody solution is added immediately through filler opening 39. The used antibody-bound hapten may be regenerated for use by the following steps: addition of glycine phosphate buffer, pH 2.5 to separate the hapten from the antibody; repeated washings with glycine buffer, each time filtering the solution by a positive pressure system through a semipermeable membrane which is permeable to all of the solution except the antibody; addition of PBS buffer, pH 7.4 to the free antibody; and sterilization of the antibody solution of by passing it through a bacterial filter, i.e. one which is permeable to the antibody but not to bacteria. The solution is then ready to be reintroduced to the chamber 32. This regeneration of the system makes it far more economical than it otherwise would be.
As shown in FIG. 6, the system may also be automatically regenerated, thereby maintaining its efficiency continuously if desired, and in any case simplifying the maintaining of the sterility of the system. In this system, the hapten-antibody is withdrawn from the second chamber 32 and delivered to a first chamber 34 of a cleaning column. Glycine phosphate buffer pH 2.5 is added from a container 40 and differential pressure is applied to accelerate migration of the free hapten across a semipermeable membrane 35 into a second chamber 24 of the cleaning column. The hapten is drained in solution into a reservoir 36, for disposal or subsequent recovery and testing. The free antibody solution is then returned to a pH of 7.4 by the addition of phosphate buffer saline from container 41. The free antibody is then ready to be returned to the second chamber 32 of the column 25. The entire process of regenerating the antibody may be controlled automatically by known differential pressure, valving and control equipment.
EXAMPLE 13
Immunoadsorption Treatment
This treatment system is adaptable to the removal of virtually any reactive species in the blood, but is particularly well adapted to, and described herein with reference to, the removal of haptens, complete antigens, and antibodies by immunological processes. As shown in FIG. 7, the apparatus for this method consists of a column 26 which includes a matrix 37 to which a binding species is linked. The binding species is a hapten, antigen (including a hapten conjugated to a carrier) or antibody which reacts specifically with the species which is to be removed from the blood. The linkage of the binding species to the matrix 37 may preferably be directly to the matrix, as when the matrix is made of a synthetic polymer such as polystyrene-latex. The linkage may also be through a suitable solid phase coating on the matrix. The antibody is then linked to the coating by one of the known methods for the preparation of immunoadsorbents, for example by a modification of one of the methods of Campbell (Campbell et al, Proc. Nat. Acad. Sci., U.S.A., 37, p. 575 (1951); Malley and Campbell, J. Am. Chem. Soc. 85, p. 487 (1963)). If any chance exists that the solid phase adsorbent may break loose from the matrix 37, suitable filters are necessary in the system. The matrix may simply be the wall of the (plastic) column if the length of the column is sufficient to provide the required surface area for interaction at the bloodbinding species interface. preferably, the matrix 37 provides a very large surface area. Such matrices include a spiral structure, as shown in FIG. 7, which requires the blood to travel in a thin layer over a large surface. Other matrices include a honeycomb (open porosity) matrix and a fill of plastic beads.
The upper part 27 of the column 26 is connected with tubing to a catheter 27a that is connected to an artery 27b of a patient 27c being treated and the lower end 28 of the column is connected to a vein 28a of the patient 27c being treated. The blood of the patient flows through the column and the species in the blood to which the binding species is specific becomes bound to the binding species, hence to the matrix. Therefore, the blood which flows from the column 26 is relatively free of the species sought to be removed.
When the column 26 has been removed from the patient, it may be renewed by elution of the species which is bound to the binding species, by known techniques, such as washing with glycine phosphate buffer, pH 2.5.
Numerous variations in the materials, devices and methods of this invention, within the scope of the appended claims, will occur to those skilled in the art in light of the foregoing disclosure. | Immunoassays of psychoactive drugs including psychotomimetic drugs, narcotic drugs, and tetrahydrocannabinols and treatment methods based on the antigenic properties of protein conjugates of these drugs. These methods are based upon treating the psychoactive substances as haptens and utilizing their protein conjugates to produce antibodies to the psychoactive materials themselves. The immunoassay methods include both agglutination and agglutination-inhibition reactions. The treatment methods include treatment of both exogenous, administered drugs (such as cannabinols, LSD, heroin and morphine) and endogenous substances (such as N,N-Dimethyltryptamine and 5-Methoxy-N,N-Dimethyltryptamine), by active immunization and also passive immunization including immunodialysis and immunoadsorption treatment methods. Devices are disclosed for carrying out the immunodialysis and immunoadsorption methods. | 0 |
FIELD OF THE INVENTION
This invention is related to the controlled delivery of photothermal or other type of energy for treatment of biological or other tissue, and more specifically, a method, system and kit for causing a subdermal wound such that upon application of a growth factor, collagenesis and further repair and healing improvement of tissue is accelerated.
BACKGROUND OF THE INVENTION
Collagen is the single most abundant animal protein in mammals, accounting for up to 30% of all proteins. The collagen molecule, after being secreted by the fibroblast cell, assembles into characteristic fibers responsible for the functional integrity of tissues making up most organs in the body. The skin is the largest organ of the body occupying the greatest surface area within the human body. As age advances and as a result of other noxious stimuli, such as the increased concentration of the ultraviolet part of the electromagnetic spectrum as radiated from the sun, structural integrity and elasticity of skin diminishes.
Crosslinks between adjacent molecules are a prerequisite for this integrity of the collagen fibers to withstand the physical stresses to which they are exposed. A variety of human conditions, normal and pathological, involve the ability of tissues to repair and regenerate their collagenous framework. In the human, 13 collagen types have been identified. Of the different identifiable types, type I is the most abundant in skin where it makes up 80 to 90% of the total collagen connective tissue. This type of collagen, however, is less dynamic in the full-grown individual than its counterparts in which collagen is involved in active remodeling. In this case the normal collagen synthesizing activities in skin is relatively quiescent exhibiting slow, almost negligible, turnover.
The extra-cellular matrix of the various connective tissues, such as skin, consists of complex macromolecules, collagen, elastin and glycosaminoglycans (GAGs). The biosynthesis of these macromolecules involves several specific reactions that are often under stringent enzymatic control. The net accumulation of connective tissues is thus, dependent upon the precise balance between the synthesis and the degradation of the connective tissue components.
Previous disclosures, such as U.S. Pat. No. 4,976,799 and U.S. Pat. No. 5,137,539 have described methods and apparatus for achieving controlled shrinkage of collagen tissue. These prior inventions have applications to collagen shrinkage in many parts of the body and describe specific references to the cosmetic and therapeutic contraction of collagen connective tissue within the skin. In the early 1980's it was found that by matching appropriate laser exposure parameters with these conditions, one had a novel process for the nondestructive thermal modification of collagen connective tissue within the human body to provide beneficial changes. The first clinical application of the process was for the non-destructive modification of the radius of curvature of the cornea of the eye to correct refractive errors, such as myopia, hyperopia, astigmatism and presbyopia. New studies of this process for the previously unobtainable tightening of the tympanic membrane or ear drum for one type of deafness have been made.
In addition to addressing the traditional method of collagen shrinkage wherein the ambient temperature is elevated within the target tissue by about 23 degrees Celsius, the “thermal shrinkage temperature” of collagen, T s , a novel method for obtaining controlled contraction of collagen at a much lower temperature has been developed. Evidence exists to elevate the mechanical role played by the GAGs in the collagenous matrix. Removing or altering these interstitial chemicals by enzymes or other reagents as disclosed in U.S. Pat. No. 5,304,169 considerably weakens the connective tissue integrity and influences the thermal transformation temperature (T s ). Shrinkage temperature may be defined, therefore, as the specific point at which disruptive tendencies exceed the cohesive forces in this tissue. This temperature, thus, makes this an actual measurement of the stability of the collagen bearing tissue expressed in thermal units.
The cause of wrinkles around the eyelids, mouth and lips is multifactorial: photodamage, smoking and muscular activity such as squinting and smiling all contribute. The end result is a general loss of elasticity, which is a textural skin condition as opposed to a skin redundancy or excess of skin tissue. The surgical injection of reconstituted collagen is commonly used in order to flatten the perioral lines. While oculoplastic surgeons may treat this problem around the eye inappropriately by blepharoplasty, it has been observed that even transconjunctival blepharoplasty for removal of prolapsed retrobulbar fat fails to address the fine periocular lines or wrinkles. Until recently, the main approach to treating these blemishes has been chemical peeling by means of trichloroacetic acid or phenol. Complications of chemical peels may include hypopigmentation, scarring, cicatricial ectropion and incomplete removal of the wrinkles.
Many patients are acutely aware of these cosmetic blemishes as evidenced by the large quantity of money spent each year in the U.S. and abroad upon home and spa remedies for a more youthful appearance. With the advent of laser technology as an alternative to chemical peels or dermabrasion, dermal ablation techniques with both the conventional carbon dioxide lasers and the high energy, short duration pulse waveform CO2 lasers, high tech solutions appear to provide substantial benefits to patients.
CO2 laser resurfacing is not a new technique. CO2 lasers have been used for several years, but regular continuous wave CO2 lasers can cause scarring due to the tissue destruction caused as heat as conducted to adjacent tissue. Even superpulse CO2 lasers produce excessive thermal damage. The Ultrapulse CO2 laser introduced by Coherent, Inc. is an attempt to assuage these drawbacks by offering a high energy, short duration pulse waveform limiting the damage to less than 50 microns allowing a char-free, layer by layer vaporization of the skin tissue.
All of the foregoing procedures depend for their success upon primary damage and the reparative potential induced by the inflammatory process in the tissue. Associated with inflammation are, of course, the four cardinal signs of inflammation of rubor (hyperemia), calor (thermal response), dolor (pain), and tumor or edema or swelling. Coincident with these manifestations is the risk of reduced resistance to infection. One must not forget that these collateral effects accompany a cosmetic enhancement procedure and, for the most part, are not associated with a therapeutic procedure. Therefore, the development of a more efficacious method would be beneficial in this regard.
Various undesirable skin conditions would be improved if the collagen underlying the region of the condition could safely be improved without damage to the overlying region. Wrinkles related to photodamage and acne scars are example of such conditions.
U.S. Pat. Nos. 4,976,709, 5,137,530, 5,304,169, 5,374,265, 5,484,432 issued to Sand, disclose a method and apparatus for controlled thermal shrinkage of collagen fibers in the cornea using light at wavelengths between 1.8 and 2.55 microns. However strong absorption of the laser energy by water limits the penetration depth to the most superficial layers of skin.
The CoolTouch (trademark) 130 laser system by CoolTouch Corp of Auburn, Calif., was first introduced at the Beverly Hills Eyelid Symposium in 1995. It utilizes a laser at a wavelength of 1.32 microns to cause thermally mediated skin treatment. In this device the treatment energy is targeted at the surface of the skin with in depth optical heating of the epidermis, papillary dermis, and upper reticular dermis. The energy is primarily absorbed in tissue water with a skin absorption coefficient of 1.4 cm−1, corresponding to an absorption depth of 0.71 cm. Scattering of the 1.32 micron wavelength light by skin microstructures alters the distribution of light from an exponential attenuation to a more complex distribution, which has much faster attenuation approximating an absorption depth of 0.1 cm. Most of the energy is absorbed in the first 250 microns of tissue. To prevent overheating of the epidermis pulsed cryogen spray precooling is used. U.S. Pat. No. 5,814,040, issued Sep. 29, 1998, describes a dynamic cooling method utilizing pulsed cryogen spray precooling. Skin treated with this device has improved texture and a reduction in wrinkles and scarring due to the long term renewal of dermal collagen without significant skin surface wounding.
U.S. Pat. No. 5,810,801 teaches a method and apparatus for treating a wrinkle in skin by targeting tissue at a level between 100 microns and 1.2 millimeters below the surface, to thermally injure collagen without erythema, by using light at wavelengths between 1.3 and 1.8 microns. The parameters of the invention are such that the radiation is maximally absorbed in the targeted region. The invention offers a detailed description of targeting the 100 micron to 1.2 mm region by utilization of a lens to focus the treatment energy to a depth of 750 microns below the surface. Because of the high scattering and absorption coefficients, precooling is utilized to prevent excess heat build up in the epidermis when targeting the region of 100 microns to 1.2 mm below the surface. The wavelength range of use is 1.3 microns to 1.8 microns in order to avoid the wavelength range of Sand. However the wavelength range of 1.4 to 1.54 microns and the range between 2.06 and 2.2 microns have identical effective attenuation coefficients in skin. Also the range from 1.15 to 1.32 microns has a fairly uniform effective attenuation coefficient in skin of about 6 to 7 cm−1. The effective attenuation length in skin for the range of wavelengths of 1.3 to 1.8 microns varies from 6 cm−1 at 1.3 microns to 52 cm−1 microns, corresponding penetration depths in skin of 200 microns to 2 millimeters. Specific laser and cooling parameters are selected so as to avoid erythema and achieve improvement in wrinkles as the long term result of a new collagen formation following treatment.
Kelly et al, report improvement in skin due to collagen remodeling after treatments with an Nd:YAG laser at 1.32 microns and cryogen spray precooling. In this case the method was designed to provide a series of treatments with parameters selected to produce erythema and mild edema, with some improvement in facial rhytids several months following a series of treatments. However, there is a risk of pigmentary change or transient pitted scarring because of the high fluence level of the laser, greater than 30 joules per square centimeter in 20 millisecond exposures, and the high level of pulse cryogen cooling.
Mucini et al. reported effective dermal remodeling using a 980 nm diode laser with a spherical handpiece which focused irradiation into the dermis avoiding the high scattering and absorption characteristic of longer wavelengths. The device requires a small lens of a few millimeters in contact with skin and results in a slow procedure when used for facial areas.
Ross et al., reported the use of an Erbium:YAG laser operating at a wavelength of 1.54 microns fired in a multiple pulsed mode has been described for eliciting changes in photodamaged skin. A chilled lens in contact with skin at the treatment site was used in an attempt to spare the epidermis. Treatment occurred during a period of several seconds with a sequence of cooling and heating with the laser and handpiece. At 1.54 microns the optical penetration depth 0.55 mm and the authors reported that the surface must be chilled before the laser exposure requiring a complex method of cooling and laser exposure. The authors state that a more superficial thermal injury may be needed than could be achieved, and that there are increased patient risks because it would demand more accurate and precise control of heating and cooling.
Bjerring et al, reported the use of a visible light laser, operating at 585 nm wavelength, to initiate collagenesis following interaction of laser energy with small blood vessels in skin.
Other methods of creating subepidermal wounding may utilize electrical current, ultrasonic energy or non-coherent light sources. In all of these methods, including those using lasers, collagen remodeling is a long-term minimal response to the application of energy. Since the objective is a non-invasive or minimally invasive procedure the stimulation of collagenesis must be below the threshold for creating an open wound, resulting in a minimal treatment.
U.S. Pat. No. 5,599,788 describes a method of producing recombinant transforming growth factor .beta.-induced H3 protein and the use of this protein to accelerate wound healing. The protein is applied directly to a wound or is used to promote adhesion and spreading of dermal fibroblasts to a solid support such as a nylon mesh which is then applied to the wound.
It is heretofore unknown to combine the adverse effect caused by excessive photothermal, mechanical or other type of energy applied to skin or other tissue coupled with a topical or other administration of growth factor(s) or wound healing factor(s) in order to amplify the natural stimulation of growth or collagenesis caused by the wound.
OBJECTS AND ADVANTAGES OF THE PRESENT INVENTION
The object of this invention is to provide a method and device for improving skin by treating layers of skin without damaging the surface or deep skin layers. It is another object of this invention to provide a method and device for improving acne scars or photodamaged skin without causing a surface injury to skin. It is another object of this invention to provide a method and device for accelerating the collagenesis after treating skin without damaging the surface of skin.
It is yet a further advantage and object of the present invention to combine the adverse effect caused by excessive photothermal, mechanical or other type of energy applied to skin or other tissue coupled with a topical or other administration of growth factor(s) or wound healing factor(s) in order to amplify the natural stimulation of growth or collagenesis caused by the wound.
The present invention circumvents the problems of the prior art and provides a system for achieving erythema and mild edema in an upper layer of skin without the risk of high fluence levels or surface wounds. The invention offer advantages over existing devices by allowing the use of lower fluence levels resulting in faster treatments and less cost. Collagen remodeling is induced by distributing the therapeutic energy over a series of more benign treatments spaced weeks apart. The collagen remodeling is further enhanced by the use of a transforming growth factor which accelerates the wound healing response. Th growth factor is applied topically in a media which will act on the skin.
Numerous other advantages and features of the present invention will become readily apparent from the following detailed description of the invention and the embodiments thereof, from the claims and from the accompanying drawings.
SUMMARY OF THE PRESENT INVENTION
The present invention is a method and apparatus for skin or other tissue treatment, using a source of thermal energy, which may be electromagnetic radiation, electrical current, or ultrasonic energy, to cause minimal-invasive thermally-mediated effects in skin or other tissue leading to a wound-healing response, in conjunction with topical agents which accelerate collagenesis in response to wound healing. The dosage and time period of application are adjusted to prevent external or surface tissue damage.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-section view of typical skin tissue.
FIG. 2 is a graph demonstrating the temperature gradient through a portion of the skin as a function of both the wavelength of incident laser energy and the depth of laser radiation penetration.
FIG. 3 is a schematic view of a microscope mounted scanner for a temperature controlled collagen shrinkage device used in the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The description that follows is presented to enable one skilled in the art to make and use the present invention, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be apparent to those skilled in the art, and the general principals discussed below may be applied to other embodiments and applications without departing from the scope and spirit of the invention. Therefore, the invention is not intended to be limited to the embodiments disclosed, but the invention is to be given the largest possible scope which is consistent with the principals and features described herein.
It will be understood that while numerous preferred embodiments of the present invention are presented herein, numerous of the individual elements and functional aspects of the embodiments are similar. Therefore, it will be understood that structural elements of the numerous apparatus disclosed herein having similar or identical function may have like reference numerals associated therewith.
Definitions
An “absorption coefficient” of a substance is a measure of the fraction of incident light that is absorbed when light is passed through the substance. The absorption coefficient (typically in units of cm −1 ) varies with the nature of the absorbing substance and with the wavelength of the light.
“Collagen” as used herein refers to any of the several types of collagen.
Collagen biosynthesis is said to be “inhibited’ when cells treated with the claimed methods secrete collagen at a rate that is less than about 70% of that of untreated cells. Preferably, treated cells secrete collagen at a rate that is less than about 50%, and more preferably less than about 30% of the rate at which untreated cells secrete collagen.
Collagen biosynthesis is said to be ‘stimulated’ when cells treated with the claimed methods secrete collagen at a rate that is greater than about 110% of the rate at which untreated cells synthesize collagen. Preferably, treated cells secrete collagen at a rate that is about 150%, and more preferably greater than about 200% greater than that of untreated cells.
“Monochromatic” light is of one wavelength or a narrow range of wavelengths. If the wavelength is in the visible range, monochromatic light will be of a single color. As used herein, “monochromatic” refers to light that has a bandwidth of less than about 100 nm. More preferably, the bandwidth will be less than about 10 nm, and most preferably less than about 1 nm.
“Non-coherent light energy” is light that is non-laser. Unlike laser light, which is characterized by having its photon wave motions in phase, the wave motions of the photons that make up non-coherent light are in a randomly occurring phase order or are otherwise out of phase.
A “wound” as used herein, refers to any damage to any tissue in a living organism. The tissue may be an internal tissue, such as the stomach lining or a bone, or an external tissue, such as the skin. As such, a wound may include, but is not limited to, a gastrointestinal tract ulcer, a broken bone, a neoplasia, and cut or abraded skin. A wound may be in a soft tissue, such as the spleen, or in a hard tissue, such as bone. The wound may have been caused by any agent, including traumatic injury, infection or surgical intervention.
A “growth factor” as used herein, includes any soluble factor that regulates or mediates cell proliferation, cell differentiation, tissue regeneration, cell attraction, wound repair and/or any developmental or proliferative process. The growth factor may be produced by any appropriate means including extraction from natural sources, production through synthetic chemistry, production through the use of recombinant DNA techniques and any other techniques, including virally inactivated, growth factor(s)-rich platelet releasate, which are known to those of skill in the art. The term growth factor is meant to include any precursors, mutants, derivatives, or other forms thereof which possess similar biological activity(ies), or a subset thereof, to those of the growth factor from which it is derived or otherwise related.
FIG. 1 is a cross-section view of typical skin tissue. The uppermost layer 98 of typical skin tissue is composed of dead cells which form a tough, horny protective coating. A thin outer layer, the epidermis 100 and a thicker inner layer, the dermis 102 . Intertwining S-like finger shaped portions 104 are at the interface between the epidermal papillary layer 106 and the dermal papillary layer 108 , and extend downward. Beneath the dermis is the subcutaneous tissue 110 , which often contains a significant amount of fat. It is the dermis layer which contains the major part of the connective collagen which is to be shrunk, in a preferred embodiment at an approximate target depth of between about 100 and 300 microns, according to the method of the present invention, though viable collagen connective tissue also exists to a certain degree in the lower subcutaneous layer as well. Other structures found in typical skin include hair and an associated follicle 112 , sweat or sebaceous glands and associated pores 114 , blood vessels 116 and nerves 118 . Additionally, a pigment layer 120 might be present. It will be understood that the drawing is representative of typical skin and that the collagen matrix will take different forms in different parts of the body. For example, in the eyelids and cheeks the dermis and subcutaneous layers are significantly thinner with less fat than in other areas. The target depth will be a function of the amount of scattering in the particular skin type and the associated absorption coefficient of the tissue. Furthermore, in some cases the actual target depth will correspond to one half the thickness of the subject tissue. For example, the target depth of tissue ½ inch thick might be about ¼ inch below the surface of the skin.
A. Damage to Tissue
Optimum Wavelength: 1.3–1.4 Microns
Methods and devices for modulating collagen biosynthesis are provided. The methods involve focusing non-coherent light energy of a predetermined wavelength to a target site where collagen biosynthesis can potentially occur. Depending upon the particular wavelength employed, collagen biosynthesis is either inhibited or stimulated. Generally, wavelengths in the red and near-infrared portion of the electromagnetic spectrum stimulate collagen biosynthesis, while longer wavelengths inhibit collagen biosynthesis.
In a preferred embodiment, to inhibit collagen biosynthesis, light energy of a wavelength greater than about 1.0 μm, preferably about 1.06 μm, is delivered to the target site for a time period sufficient to accomplish the inhibition. In a preferred embodiment, stimulation of collagen biosynthesis occurs when light energy at 640 nm or 900 nm is delivered to a target site for a time period sufficient to accomplish the stimulation.
The optimal wavelength within these ranges is influenced by whether the light energy must pass through overlying tissue before reaching the target site. In such cases where the target site is shielded by other tissue, the light energy is transmitted through the shielding tissue and focused on the target site so that the desired energy level is obtained at the target site. Because transmission of light through tissue is highly wavelength specific, one should choose a wavelength that is not highly absorbed by overlying tissue.
To modulate collagen biosynthesis, an amount of light energy of an appropriate predetermined wavelength is delivered to the target site that is sufficient to have the desired stimulatory or inhibitory effect. The amount of energy delivered to a target site is a function of several factors, including the output of the light source, the energy flux at the target site as determined by the source output and the degree of focusing achieved by the light delivery apparatus, and the time period for which the target site is exposed to the light energy. Another factor, discussed below, is the nature of any tissue overlying the target site.
The appropriate combinations of energy flux and time period for a desired effect on collagen biosynthesis can be determined empirically. For example, one can determine the effect on collagen biosynthesis of irradiating cells growing in tissue, preferably in monolayers, with light energy of a given wavelength, energy flux, and time period.
In general, the desired energy density delivered to the target site is between about 1.0×10 3 and 1.6×10 3 Joules cm −2 . Preferably, the energy density at the target site is about 1.1×10 3 Joules cm −2 . For most applications, the amount of energy delivered to the target site should be sufficient to modulate collagen biosynthesis, but should not be so great as to cause a significant decrease in cell proliferation. For example, 1.7×10 3 Joules cm −2 of 1064 nm laser light is known to inhibit fibroblast proliferation. Thus, an energy that is between about 1.1×10 3 and about 1.7×10 3 Joules cm −2 is preferred.
To achieve the desired energy density, the light energy is delivered to the target site for a sufficient time period. The time period necessary depends on the energy flux delivered to the target site by the light delivery apparatus. The light can be delivered as a single pulse or as a multiplicity of pulses. Often, the use of short pulses is preferred, as the shorter pulses cause less undesirable heating of the tissues surrounding the target site than does a single pulse of longer duration. Preferably, a higher-power shorter-duration pulse is used, rather than a low-power long-duration pulse. Typical pulse durations are between about 0.01 and 1.0 seconds, most preferably about 0.1 seconds.
Light Delivery Apparatus
Many types of non-laser light sources are suitable for producing the noncoherent light that is used in the methods and apparatus of the present invention. For example, one can employ polychromatic light sources such as heated lamp filaments or gas filled vacuum tubes. Commercially available light sources are discussed in, for example, LaRocca, A., “Artificial Sources,” In Handbook of Optics , Vol. 1, Ch. 10, Bass et al., eds., McGraw-Hill, New York, 1995, pp. 10.3–10.50, and references cited therein.
If a polychromatic light source is used, the light energy is preferably made monochromatic or nearly monochromatic by suitable methods known to those of skill in the art. For example, one can direct the polychromatic light through a filter or a series of filters that transmits only light of the desired wavelength or range of wavelengths. Suitable filters are described in, for example, Dobrowolski, J. A., “Optical Properties of Films and Coatings,” In Handbook of Optics , Vol. 1, Ch. 42, Bass et al., eds., McGraw-Hill, New York, 1995, pp. 42.342.130, and references cited therein. Bandpass filters are reviewed, for example, in Macleod, H. A., 7hin film Optical E 71 ters , McGraw-Hill, New York, 1986; ‘Metal-dielectric Interference Filters,” in Physics of 7 hin Films , Hass et al., eds., Academic Press, New York, 1977, vol. 9, pp. 73–144; Barr, “The Design and Construction of Evaporated Multilayer Filters for Use in Solar Radiation Technology,” in Advances in Geophysics , Drummond, ed., Academic Press, New York, 1970, pp. 391–412).
In a preferred embodiment, a monochromatic or nearly monochromatic light source is used. By choosing a light source that emits monochromatic or nearly monochromatic light, the need to filter or focus the light to the desired wavelength is eliminated. Several types of monochromatic or nearly monochromatic light source are known to those of skill in the art. See, e.g., LaRocca, supra., for types and sources of monochromatic light sources.
Light-emitting diodes (LEDs) are a preferred light source for use in the claimed invention. LEDs are described, for example, in Haitz et al., “Light-Emitting Diodes,” In Handbook of Optics , Vol. 1, Ch. 12, Bass, M., ed., McGraw-Hill, New York, pp. 12.1–12.39. Both surface and edge emitters are commercially available, in continuous and pulse-operated modes. Commercially available LEDs that are useful in the claimed methods emit wavelengths of 830, 904, 1060, 1300, and 1550 nm. In preferred embodiments of the present invention, the 830 and 904 nm LEDs are useful for stimulating collagen biosynthesis, while in other preferred embodiments of the present invention, the 1060, 1300, and 1550 nm LEDs are appropriate for inhibition.
Light energy used in the claimed methods is preferably collimated, in addition to being of a predetermined wavelength or range of wavelengths. Collimation can be achieved by any of several methods known to those of skill in the art. For example, passing light through fiber optics of various core diameters will achieve collimation. Suitable fiber optic instrumentation is available from EG&G Opto-Electronics of Salem, Mass. Optical fibers are described, for example, in Brown, T. G., “Optical Fibers and Fiber-Optic Communications,” In Handbook of Optics, Vol. U, Ch. 10, Bass, M., ed., McGraw-Hill, New York, pp. 10.1 et seq.
The light energy is focused to the target site as a spot having a diameter that is appropriate for the particular treatment being undertaken. Where inhibition of collagen biosynthesis in a relatively small area is used, the light is focused to a correspondingly small spot at the target site. Typically, the light energy is focused to a spot with a diameter in the range of about 0.25 to about 2.0 millimeters. The focusing step also concentrates the light to an energy flux that is sufficient to achieve the desired inhibition when delivered to the target site for an appropriate period of time.
Methods for focusing light to achieve a desired energy flux and spot diameter are known to those of skill in the art. For example, a focusing lens made of glass, silica, or refractory material such as diamond or sapphire is commonly employed. In a preferred embodiment, the focusing lens directs the non-coherent light energy to an optical fiber of an appropriate core diameter and composition. For example, a 100 μm diameter low-OH silica optic fiber is appropriate. A fiber that produces a relatively low amount of transmission loss is preferred, preferably less than about 15% loss over a length of up to ten meters. The fiber is typically mounted in a shaft for delivery of the non-coherent light energy to the tissue. The output end of the shaft is preferably fitted with an output tip that can dir maintaining the delivery end of the fiber a desired distance away from the tissue. This distance can be varied by substituting a longer or shorter output tip, or by slidably adjusting the position of the output tip on the shaft.
For some applications, it is desirable to use an output tip that directs the noncoherent focused light out of its side, rather than through the end of the fiber. Means for accomplishing this are known to those of skill in the art. For example, U.S. Pat. No. 5,129,895 describes the use of a reflecting surface at the end of the fiber combined with lens action on the fiber side.
The invention also provides an apparatus for modulating collagen biosynthesis according to the methods described herein. The apparatus comprises a source of noncoherent light energy, a means for collimating the light energy generated by the light source, and a means for focusing the collimated light energy to a target site. The apparatus delivers sufficient light energy to the target site to modulate collagen biosynthesis.
Therapeutic Applications
The claimed methods for modulating collagen biosynthesis are useful in treating many conditions. Depending upon the condition being treated, either inhibition or stimulation of collagen biosynthesis may be desired.
The invention also provides methods for stimulating collagen biosynthesis. These methods are also useful in the clinical setting. For example, stimulation of collagen biosynthesis is often desirable in the early stages of wound healing. The procedures employed are similar to those used for inhibiting collagen biosynthesis, except for the wavelength of light delivered to the target site. To stimulate collagen biosynthesis, one delivers light in the red or near-infrared range of the electromagnetic spectrum to the target site. For example, light energy at 640 nm or 900 nm stimulates collagen biosynthesis when delivered to a target site at specific energy densities and durations.
To enhance wound healing, collimated fight energy of an appropriate wavelength is delivered to the wound at an energy density sufficient to stimulate collagen biosynthesis. The light energy can be delivered as a single pulse, or more preferably, as a series of short pulses. The use of short pulses reduces the likelihood of undesired heating of the tissue. Preferably, the light energy delivered is sufficient to stimulate collagen biosynthesis, but is insufficient to inhibit cell proliferation.
FIG. 2 is a graph demonstrating the temperature gradient through a portion of the skin as a function of both the wavelength of incident laser energy and the depth of laser radiation penetration. No external cooling is used. The graph demonstrates a change in temperature (ΔT) of about 60 degrees Celsius and all curves are shown for the time point 1 millisecond following exposure to the laser energy. The graph shows three lines corresponding to laser wavelengths of 10.6 microns, 1.3–1.4 microns and 1.06 microns.
The present invention utilizes laser energy having a wavelength between about 1 and about 12 microns, more preferably between about 1.2 and about 1.8 microns, and more preferably about 1.3–1.4 microns. This type of laser energy is most frequently produced by a Nd:YAG, Nd:YAP or Nd:YALO-type laser. A laser operating at these wavelengths may either have a high repetition pulse rate or operate in a continuous wave mode. This laser has been investigated in the medical community as a general surgical and tissue welding device, but has not been used for collagen tissue shrinkage in the past. Indeed, the prior art teaches away from the use of laser energy at 1.3–1.4 microns for shrinking human collagen.
The Nd:YAG, Nd:YAP and Nd:YALO-type lasers are sources of coherent energy. This wavelength of 1.3–1.4 microns is absorbed relatively well by water, and as a result is attractive for tissue interaction. It is also easily transmitted through a fiber optic delivery system as opposed to the rigid articulated arm required for the CO 2 laser. Very precise methods of controlling laser systems and optically filtering produced light currently exist. By selecting the appropriate combination of resonance optics and/or antireflection coatings, wavelengths in the range of 1.3–1.4 microns and even 1.32–1.34 microns can be produced.
FIG. 3 is a schematic view of a microscope mounted scanner for a temperature controlled collagen shrinkage device used in the present invention. In this view, a laser console 60 is installed adjacent a floor-mounted microscope 62 . A fiber optic cable 64 conducts laser energy from the laser source to the scanner 66 . A laser delivery attachment 68 may be necessary to conduct the laser energy in an appropriate beam pattern and focus. In this embodiment of the invention, servo feedback 70 signals are also conducted along the fiber optic back to the laser console. The servo feedback signals could also be directed back to the laser console via an additional fiber optic or other wiring or cabling. This servo feedback may comprise thermal or optical data obtained via external sensors or via internal systems, such as a fiber-tip protection system which attenuates the laser energy transmitted, to provide control in operation and to prevent thermal runaway in the laser delivery device. Thus, a thermal feedback controller 72 will regulate the laser energy being transmitted. This controller can comprise an analog or digital PI, PD or PID-type controller, a microprocessor and set of operating instructions, or any other controller known to those skilled in the art. Other preferred embodiments can also be provided with additional features. For example, the surgeon or technician operating the laser could also manipulate an energy adjust knob 74 , a calibration knob 76 and a footpedal 78 . Thus, in a preferred embodiment, a very accurately adjustable system is provided which allows a surgeon to deliver laser energy via a computer controlled scanning device, according to instructions given by the surgeon or an observer inspecting the region of the skin where collagen is to be shrunk through a very accurate microscope. Once a region to be treated is located, the scanner can deliver a very precise, predetermined amount of laser energy, in precisely chosen, predetermined regions of the skin over specific, predetermined periods of time.
In a preferred embodiment, the invention utilizes an Nd:YAG laser at 1320 nm wavelength, (such as the CoolTouch 130, CoolTouch Corp., Auburn, Calif.) as the source of treatment energy. At 1320 nm the absorption depth in tissue is such that energy is deposited throughout the upper dermis, with most absorption in the epidermis and upper dermis, a region including the top 200 to 400 microns of tissue. The energy falls off approximately exponentially with the highest level of absorbed energy in the epidermis. Optical heating of skin follows exposure to the laser energy. If the time of exposure to the laser is very short compared to the time required for heat to diffuse out of the area exposed, the thermal relaxation time, than the temperature rise at any depth in the exposed tissue will be proportional to the energy absorbed at that depth. However, if the pulse width is comparable or longer to the thermal relaxation time of the exposed tissue than profile of temperature rise will not be as steep. Conduction of thermal energy occurs at a rate proportional to the temperature gradient in the exposed tissue. Lengthening the exposure time will reduce the maximum temperature rise in exposed tissue.
For example at 1.3 microns the laser pulse width may be set to 30 milliseconds and fluence to less than 30 joules per square centimeter. This prevents excessive heat build up in the epidermis, which is approximately the top 100 microns in skin. The papillary dermis can then be heated to a therapeutic level without damage to the epidermis. The epidermis will reach a temperature higher than but close to that of the papillary dermis.
The epidermis is more resilient in handling extremes of temperature than most other tissue in the human body. It is therefore possible to treat the papillary dermis in conjunction with the epidermis without scarring or blistering, by treating both layers with laser energy and allowing a long enough exposure time such that the thermal gradient between the epidermis and underlying layers remains low. In this way the underlying layers can be treated without thermal damage to the epidermis.
A wavelength of 1.3 microns is used in this embodiment to treat the middle layers of skin. Other wavelengths such as 1.45 or 2.1 microns may by used to treat more superficial layers of skin by this method. Visible light lasers, intense pulsed light sources, energy delivery devices such as electrical generators, ultrasonic transducers, and microdermabrasion devices may also be used to initiate a wound healing response without significant surface wounding. The use of growth factors in conjunction with these devices allows for more superficial treatments and improved response.
In one embodiment the invention utilizes an Nd:YAG laser at 1320 nm wavelength, (such as the CoolTouch 130, CoolTouch Corp., Auburn Calif.) as the source of treatment energy. At 1320 nm the absorption depth in tissue is such that energy is deposited throughout the upper dermis, with most absorption in the epidermis and upper dermis, a region including the top 200 to 400 microns of tissue. The energy falls off approximately exponentially with the highest level of absorbed energy in the epidermis. Optical heating of skin follows exposure to the laser energy. If the time of exposure to the laser is very short compared to the time required for heat to diffuse out of the area exposed, the thermal relaxation time, than the temperature rise at any depth in the exposed tissue will be proportional to the energy absorbed at that depth. However, if the pulse width is comparable or longer to the thermal relaxation time of the exposed tissue than profile of temperature rise will not be as steep. Conduction of thermal energy occurs at a rate proportional to the temperature gradient in the exposed tissue. Lengthening the exposure time will reduce the maximum temperature rise in exposed tissue.
The present invention also incorporates herein by specific reference, in their entireties, the following issued U.S. patents:
U.S. Pat. No. 5,885,274 issued Mar. 3, 1999 titled FLASH LAMP FOR DERMATOLOGICAL TREATMENT, U.S. Pat. No. 5,968,034 issued Oct. 19, 1999 titled PULSED FILAMENT LAMP FOR DERMATOLOGICAL TREATMENT, U.S. Pat. No. 5,820,626 issued Oct. 13, 1998 titled COOLING LASER HANDPIECE WITH REFILLABLE COOLANT RESERVOIR, U.S. Pat. No. 5,976,123 issued Nov. 2, 1999 titled HEART STABILIZATION, U.S. Pat. No. 6,273,885 issued Aug. 14, 2001 titled HANDHELD PHOTOEPILATION DEVICE AND METHOD.
The present invention also incorporates herein by specific reference, in their entireties, the following pending U.S. patent applications: application Ser. No. 09/185,490 filed Nov. 3, 1998 titled SUBSURFACE HEATING OF TISSUE, application Ser. No. 09/364,275 filed Jul. 29, 1999 titled THERMAL QUENCHING OF TISSUE.
B. Wound Healing and Growth Factors
When a tissue is injured, polypeptide growth factors, which exhibit an array of biological activities, are released into the wound where they play a crucial role in healing (see, e.g., Hormonal Proteins and Peptides (Li, C. H., ed.) Volume 7, Academic Press, Inc., New York, N.Y. pp. 231–277 (1979) and Brunt et al., Biotechnology 6:25–30 (1988)). These activities include recruiting cells, such as leukocytes and fibroblasts, into the injured area, and inducing cell proliferation and differentiation. Growth factors that may participate in wound healing include, but are not limited to: platelet-derived growth factors (PDGFs); insulin-binding growth factor-1 (IGF-1); insulin-binding growth factor-2 (IGF-2); epidermal growth factor (EGF); transforming growth factor-.alpha. (TGF-.alpha.); transforming growth factor-.beta. (TGF-.beta.); platelet factor 4 (PF-4); and heparin binding growth factors one and two (HBGF-1 and HBGF-2, respectively).
PDGFs are stored in the alpha granules of circulating platelets and are released at wound sites during blood clotting (see, e.g., Lynch et al., J. Clin. Invest. 84:640–646 (1989)). PDGFs include: PDGF; platelet derived angiogenesis factor (PDAF); TGF-.beta.; and PF4, which is a chemoattractant for neutrophils (Knighton et al., in Growth Factors and Other Aspects of Wound Healing: Biological and Clinical Implications, Alan R. Liss, Inc., New York, N.Y., pp. 319–329 (1988)). PDGF is a mitogen, chemoattractant and a stimulator of protein synthesis in cells of mesenchymal origin, including fibroblasts and smooth muscle cells. PDGF is also a nonmitogenic chemoattractant for endothelial cells (see, for example, Adelmann-Grill et al., Eur. J. Cell Biol. 51:322–326 (1990)).
IGF-1 acts in combination with PDGF to promote mitogenesis and protein synthesis in mesenchymal cells in culture. Application of either PDGF or IGF-1 alone to skin wounds does not enhance healing, but application of both factors together appears to promote connective tissue and epithelial tissue growth (Lynch et al., Proc. Natl. Acad. Sci. 76:1279–1283 (1987)).
TGF-.beta. is a chemoattractant for macrophages and monocytes. Depending upon the presence or absence of other growth factors, TGF-.beta. may stimulate or inhibit the growth of many cell types.
Other growth factors, such as EGF, TGF-.alpha., the HBGFs and osteogenin are also important in wound healing. Topical application of EGF accelerates the rate of healing of partial thickness wounds in humans (Schultz et al., Science 235:350–352 (1987)). Osteogenin, which has been purified from demineralized bone, appears to promote bone growth (see, e.g., Luyten et al., J. Biol. Chem. 264:13377 (1989)). In addition, platelet-derived wound healing formula, a platelet extract which is in the form of a salve or ointment for topical application, has been described (see, e.g., Knighton et al., Ann. Surg. 204:322–330 (1986)).
The heparin binding growth factors (HBGFs), including the fibroblast growth factors (FGFs), which include acidic HBGF (aHBGF also known as HBFG-1 or FGF-1) and basic HBGF (bHBGF also known as HBGF-2 or FGF-2), are potent mitogens for cells of mesodermal and neuroectodermal lineages, including endothelial cells (see, e.g., Burgess et al., Ann. Rev. Biochem. 58:575–606 (1989)). In addition, HBGF-1 is chemotactic for endothelial cells and astroglial cells. Both HBGF-1 and HBGF-2 bind to heparin, which protects them from proteolytic degradation. The array of biological activities exhibited by the HBGFs suggests that they play an important role in wound healing.
Basic fibroblast growth factor (FGF-2) is a potent stimulator of angiogenesis and the migration and proliferation of fibroblasts (see, for example, Gospodarowicz et al., Mol. Cell. Endocinol. 46:187–204 (1986) and Gospodarowicz et al., Endo. Rev. 8:95–114 (1985)). Acidic fibroblast growth factor (FGF-1) has been shown to be a potent angiogenic factor for endothelial cells (Burgess et al., supra, 1989). Other FGF's may be chemotactic for fibroblasts. Growth factors are, therefore, potentially useful for specifically promoting wound healing and tissue repair.
“HBGF-1,” which is also known to those of skill in the art by alternative names, such as endothelial cell growth factor (ECGF) and FGF-1, as used herein, refers to any biologically active form of HBGF-1, including HBGF-1.beta., which is the precursor of HBGF-1.alpha. and other truncated forms, such as FGF. U.S. Pat. No. 4,868,113 to Jaye et al., herein incorporated by reference, sets forth the amino acid sequences of each form of HBGF. HBGF-1 thus includes any biologically active peptide, including precursors, truncated or other modified forms, or mutants thereof that exhibit the biological activities, or a subset thereof, of HBGF-1.
Other growth factors may also be known to those of skill in the art by alternative nomenclature. Accordingly, reference herein to a particular growth factor by one name also includes any other names by which the factor is known to those of skill in the art and also includes any biologically active derivatives or precursors, truncated mutant, or otherwise modified forms thereof.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. Although any methods and materials similar or equivalent to those described can be used in the practice or testing of the present invention, the preferred methods and materials are now described. All publications and patent documents referenced in the present invention are incorporated herein by reference.
While the principles of the invention have been made clear in illustrative embodiments, there will be immediately obvious to those skilled in the art many modifications of structure, arrangement, proportions, the elements, materials, and components used in the practice of the invention, and otherwise, which are particularly adapted to specific environments and operative requirements without departing from those principles. The appended claims are intended to cover and embrace any and all such modifications, with the limits only of the true purview, spirit and scope of the invention. | A method and apparatus for treatment of skin or other tissue, using a source of thermal, electromagnetic radiation, electrical current, ultrasonic, mechanical or other type of energy, to cause minimally-invasive thermally-mediated effects in skin or other tissue which stimulates a wound-healing response, in conjunction with topical agents or other wound healing compositions, for application on the skin or other tissue which accelerate collagenesis, such as in response to wound healing. The dosage and time period of application of the compositions are adjusted to prevent external or surface tissue damage. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates to surgical cassettes and more particularly to a system for latching surgical cassettes.
The use of cassettes with surgical instruments to help manage irrigation and aspiration flows into a surgical site are well-known. U.S. Pat. Nos. 4,493,695, 4,627,833 (Cook), 4,395,258 (Wang, et al.), 4,713,051 (Steppe, et al.), 4,798,580 (DeMeo, et al.), 4,758,238, 4,790,816 (Sundblom, et al.) and 5,267,956, 5,364,342 (Beuchat) all disclose tubeless or tube-type surgical cassettes and are incorporated herein in their entirety by reference.
One of the primary function of the cassettes disclosed above is to control aspiration (vacuum) level at the surgical site. The vacuum generating device generally is contained within the surgical system control console and may be a venturi, diaphragm or peristaltic pump. Other mechanical interactions between the cassette and the console are also required, for example, to control fluid flow within the cassette and for monitoring the vacuum level within the cassette. These interaction require that the cassette be held securely within the console, with positive, aligned contact between the cassette and the console. Prior to the present invention, cassettes generally were secured within the console by a tight, friction fit or by a spring tab. These frictional methods of securing the cassette within the console can make the cassette difficult to insert and remove from the cassette from the console. In addition, these frictional methods do not positively lock the cassette within the console, so inadvertent removal of the cassette is possible.
Accordingly, a need exists for a mechanism to assist in latching a surgical cassette within a surgical console.
BRIEF DESCRIPTION OF THE INVENTION
The present invention generally includes an articulating clamp mounted on the end of a pneumatic or hydraulic cylinder. The clamp interacts with a slot, tab or tang on the cassette housing to hold the cassette firmly within a surgical console. The clamp articulates in response to extension or contraction of the cylinder to grasp securely the cassette tab and hold the cassette within the console.
Accordingly, one objective of the present invention is to provide a mechanism for latching a cassette within a surgical console.
Another objective of the present invention is to provide an articulating clamp that cooperates with a slot, tab or tang on a surgical cassette to hold the cassette firmly within a surgical console.
Still another objective of the present invention is to provide an articulating clamp mounted on the end of a cylinder that cooperates with a slot, tab or tang on a surgical cassette to hold the cassette firmly within a surgical console.
These and other objectives and advantages of the present invention will become apparent from the detailed description and claims which follow.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded perspective view of the present invention and also illustrating one type of surgical cassette that can be used with the present invention.
FIG. 2 is an exploded perspective view of the articulating clamp and cylinder illustrated in FIG. 1.
FIG. 3 is a perspective view of the articulating clamp and cylinder similar to FIG. 2, but with the clamp assembled on the cylinder.
FIG. 4 is a perspective, partial cross-sectional view of the clamp of present invention cooperating with a recess in the surgical cassette illustrated in FIG. 1.
FIG. 5 is a perspective, partial cross-sectional view of the clamp of the present invention, similar to FIG. 4, but illustrating the movement of the clamp during clamping and unclamping of the cassette.
FIG. 6 is a front elevational, partial cross-sectional view of the clamp of present invention cooperating with a recess in the surgical cassette illustrated in FIG. 1.
FIG. 7 is a front elevational, partial cross-sectional view of the clamp of the present invention, similar to FIG. 6, but illustrating the clamp in the unclamped position.
FIG. 8 is a partial side elevational view of the clamp of present invention cooperating with a recess in the surgical cassette illustrated in FIG. 1.
FIG. 9 is a partial side elevational view of the clamp of the present invention, similar to FIG. 8, but illustrating the clamp in the unclamped position.
DETAILED DESCRIPTION OF THE INVENTION
As best seen in FIGS. 1-3, latching apparatus 10 of the present invention generally includes clamp 12 and cylinder 14. Clamp 12 may be of any suitable size and shape and includes passage 54, slotted mounting hole 16, prongs 18, flange 38 and fittings 20 and 22. Passage 54 and fittings 20 and 22 allow fluid communication between console 24 and cassette 26 through clamp 12. Clamp 12, prongs 18 and flange 38 preferably are made from steel, stainless steel, aluminum or titanium and formed in a single piece by machining, casting or forging. Fitting 22 preferably is formed of a resilient material such as silicone rubber or other equivalent elastomer and press fit into a recess (not shown) in clamp 12. Fitting 20 preferably is a slip fitting and made from steel, stainless steel, aluminum, titanium or suitable plastic. Fitting 20 may be mounted on clamp 12 by a press fit or threaded coupling and may include sealing washer 56.
Cylinder 14 may be any suitable pneumatic or hydraulic cylinder, such as pneumatic cylinder Model No. 56255-1173 manufactured by American Cylinder, and generally includes yoke 28, housing 30, rod 48, fittings 32 and pin 34. Yoke 28 is sized to cradle flange 38 on clamp 12 and may be threadably attached to rod 48. Flange 38 is held within yoke 28 by pin 34, which telescopes through slotted hole 16 so that pin 34 is frictionally held in yoke 28, but slides easily within slotted hole 16. Clamp 12 is attached to console 24 and held within recess 42 on console 24 by pin 40, which allows clamp 12 to pivot on pin 40 about hole 44 within recess 42, as shown in FIGS. 4-9. Yoke 28, housing 30, fittings 32 and pins 34 and 40 may be made of any suitable material such as brass, steel, stainless steel, aluminum or titanium.
As seen in FIGS. 4, 6 and 8, in its relaxed state, cylinder 14 is extended. Causing cylinder 14 to be extended in its relaxed state ensures that cassette 26 cannot be removed from console 24 if the power to console 24 is temporarily interrupted. When cylinder 30 is extended, rod 48 pushes yoke 28 forward, causing clamp 12 to pivot downward about pin 40 while pin 34 rides within slotted hole 16. The downward pivot of clamp 12 about pin 40 causes prongs 18 to rest below top edge 46 of cassette 26 and against recessed clamping faces 50 on cassette 26, thereby holding cassette 26 rigidly wig console 24. As best seen in FIGS. 6 and 8, when cassette 26 is held wig console 24, fitting 22 is held tightly against mating fitting 52 on cassette 26, allowing fitted communication with cassette 26 through fitting 22, passage 54 in clamp 12 and fitting 20. Cassette 26 may be any suitable surgical cassette having clamping faces 50 sized and shaped to receive prongs 18 on clamp 12.
As seen in FIGS. 5, 7 and 9, to insert or remove cassette 26, a control means (not shown) within console 24 causes cylinder 14 to draw back on rod 48 and yoke 28, allowing clamp 12 to pivot about pin 40 while pin 34 rides within slotted hole 16. The pivoting action of clamp 12 allows prongs 18 to be raised about top edge 46 of cassette 26. In this position, cassette 26 may be easily removed or inserted.
This description is given for purposes of illustration and explanation. It will be apparent to those skilled in the relevant art that changes and modifications may be made to the invention described above without departing from its scope or spirit. | A cassette latching mechanism generally including an articulating clamp mounted on the end of a pneumatic cylinder. The clamp interacts with a slot, tab or tang on the cassette housing to hold the cassette firmly within a surgical console. | 0 |
BACKGROUND
[0001] The present invention relates to an interface circuit for protecting a telephone from overcurrents flowing in continuously due to transient overvoltages such as surge voltages or mixing etc. of mains power lines and subscriber lines.
[0002] A protection circuit is provided at an interface of a telephone and subscriber lines because of the possibility of a transient indirect lightening stroke accompanying a lightening strike being propagated to subscriber lines hanging in space or the possibility of overcurrents continuously flowing over a long period of time to a certain extent due to mixing with a mains power line. Configurations such as, for example, connecting a varistor element between two subscriber lines or connecting a varistor element between a subscriber line and earth are well-known as lightening surge countermeasures. When a transient surge voltage exceeding the varistor voltage is applied to a subscriber line, the surge voltage is absorbed as a result of the varistor element making a transition to conducting mode, and a speech circuit within the telephone is protected.
[0003] Further, configurations where, for example, a PTC thermistor (Positive Temperature Coefficient Thermistor) is interposed at an interface between a subscriber line and a telephone are also well known as a countermeasure for heating and combustion of a telephone due to mixing of subscriber lines and mains power lines. When an overcurrent flows into a PCT thermistor continuously over a certain period of time, input impedance of the interface increases in accompaniment with rise in element temperature and flowing in of overcurrents to within the telephone can be suppressed.
SUMMARY
[0004] However, in a telephone interface circuit using a semiconductor element for opening and closing a connection between a speech circuit and subscriber lines, strict adherence to ratings for current and voltage are necessary in order to avoid a secondary breakdown phenomenon peculiar to the semiconductor element, and use of an expensive Sidac® as a protection circuit is necessary.
[0005] The present invention therefore sets out to resolve the problem of providing a low-price telephone interface circuit capable of maintaining reliability of an interface circuit for protecting a telephone from the flowing in of overcurrents.
[0006] In order to resolve the aforementioned problems, a telephone interface circuit of the present invention comprises a first transistor for controlling opening and closing between a speech circuit and subscriber lines, a second transistor for controlling the first transistor to turn on and off, a positive feedback circuit connecting a collector terminal of the first transistor and a base terminal of the second transistor, an overcurrent detection circuit detecting overcurrent flowing in to the subscriber lines, and a breaker circuit for turning off the first transistor by lowering the base potential of the second transistor to a low potential when overcurrent is detected at the overcurrent detection circuit. Here, the base terminal of the first transistor and a collector terminal of the second transistor are connected. Further, when off-hook, the base potential of the second transistor is controlled in such a manner as to become a high potential by a microcomputer.
DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a circuit diagram of a telephone interface circuit of this embodiment.
[0008] FIG. 2 is a graph showing change over time of a voltage across a base and an emitter of a transistor when an overcurrent is continuously applied to a subscriber line.
[0009] FIG. 3 is a graph showing change in time of a surge voltage applied across subscriber lines.
[0010] FIG. 4 is a graph showing change in time of a current passing through a transistor when a surge voltage is applied across subscriber lines in a telephone interface of the related art.
[0011] FIG. 5 is a graph showing change in time of a current passing through a transistor when a surge voltage is applied across subscriber lines in a telephone interface of this embodiment.
DETAILED DESCRIPTION
[0012] FIG. 1 shows a circuit configuration for a telephone interface circuit 10 of this embodiment.
[0013] The telephone interface circuit 10 controls interfacing between a speech circuit 30 and subscriber lines L 1 , L 2 . The telephone interface circuit 10 is mainly comprised of a varistor element V 1 , Zener diode 40 , diode bridge 20 , transistors Q 1 , Q 2 , positive feedback circuit 50 , overcurrent detection circuit 40 , and breaker circuit 70 .
[0014] The varistor element V 1 is arranged at a front stage of the diode bridge 20 , and absorbs overvoltage (for example, high voltages of 270V or more) between the subscriber lines L 1 and L 2 .
[0015] The Zener diode 40 is arranged at a front stage of the speech circuit 30 , and absorbs overvoltage (for example, high voltages of 9V or more) between the subscriber lines L 1 and L 2 .
[0016] The diode bridge 20 regulates the signal flowing through the subscriber lines L 1 , L 2 for supply to the speech circuit 30 . The diode bridge 20 is configured from four diodes D 1 to D 4 .
[0017] The overcurrent detection circuit 40 is a circuit for detecting overvoltages between the subscriber lines L 1 , L 2 . The overcurrent detection circuit 40 contains a resistor R 23 .
[0018] The breaker circuit 70 is a circuit for turning the transistor Q 2 off by applying a reverse bias voltage across base terminal B 2 and emitter terminal E 2 of transistor Q 2 when an overvoltage is applied between the subscriber lines L 1 , L 2 . Breaker circuit 70 contains a Zener diode D 20 .
[0019] When the telephone is off the hook, the transistor Q 1 is turned on so as to connect the subscriber lines L 1 , L 2 and speech circuit 30 , while when the telephone is on the hook, the transistor Q 1 is turned off so that the subscriber lines L 1 and L 2 and the speech circuit 30 are disconnected.
[0020] The emitter terminal E 1 of transistor Q 1 is connected to the subscriber line L 1 .
[0021] The base terminal B 1 of the transistor Q 1 is connected to collector terminal C 2 of transistor Q 2 via a resistor R 12 .
[0022] The collector terminal C 1 of the transistor Q 1 branches, with one branch connected to the speech circuit 30 and the other branch being connected to the positive feedback circuit 50 . The positive feedback circuit 50 has a capacitor C 22 .
[0023] A resistor R 14 is connected across emitter terminal E 1 and base terminal B 1 of transistor Q 1 .
[0024] Base terminal B 2 of transistor Q 2 branches into three, with one branch being connected to the positive feedback circuit 50 , another branch being connected to the breaker circuit 70 , and the remaining branch being connected to a microcomputer (not shown) via an RC circuit (a circuit containing a resistor R 24 and a capacitor C 21 ).
[0025] Emitter terminal E 2 of the transistor Q 2 is connected to the subscriber line L 2 via the diode bridge 20 .
[0026] As a result of the above circuit configuration, the transistors Q 1 and Q 2 and the positive feedback circuit 50 function as a Schmitt trigger 60 . Namely, the base terminal B 2 of transistor Q 2 functions as a gate terminal G of the Schmitt trigger 60 .
[0027] Transistor Q 1 is a switching element comprised of a PNP transistor and transistor Q 2 is a switching element comprised of an NPN transistor.
[0028] A terminal HC is connected to a microcomputer (not shown). The microcomputer (not shown) controls base potential of the transistor Q 2 by controlling the potential of terminal HC at the time of an off-hook operation, on-hook operation, or dial pulse transmission operation, etc.
[0029] For example, when off-hook, the potential of the terminal HC is controlled to be a high potential as a result of control by the microcomputer (not shown). In doing so, as a result of the rise in potential of the terminal HC, the base potential of the transistor Q 2 rises, and the transistor Q 2 turns on. As a result, the base potential of transistor Q 1 rises, and the transistor Q 1 therefore turns on. The rise in the collector potential of the transistor Q 1 is then positively fed-back to the base terminal B 2 of transistor Q 2 via the positive feedback circuit 50 . At this time, the capacitor C 22 has a function for shortening the turn on time of the transistor Q 2 .
[0030] When a dial input takes place in an off-hook state, the microcomputer (not shown) controls the potential of the terminal HC so as to correspond to the dial input. As a result, the transistor Q 1 sends a dial pulse signal.
[0031] On the other hand, when on-hook, the potential of the terminal HC is controlled to be a low potential as a result of control by the microcomputer (not shown). As a result, the base potential of transistor Q 2 falls, and the transistor Q 2 therefore turns off. In doing so, the base potential of transistor Q 1 falls, and the transistor Q 1 therefore turns off.
[0032] Next, a description is given of the operation when an overvoltage is applied to the subscriber lines L 1 , L 2 .
[0033] When an overvoltage is applied to the subscriber lines L 1 , L 2 , a large voltage drop occurs at the overcurrent detection circuit 40 . When this voltage drop exceeds the Zener voltage, the Zener diode D 20 enters a breakdown state. The breaker circuit 70 then causes the base potential of the transistor Q 2 to fall. At this time, a reverse bias voltage is applied across the base terminal B 2 and emitter terminal E 2 of the transistor Q 2 . The transistor Q 2 therefore turns off the instant (within two microseconds) the overvoltage is applied across the subscriber lines L 1 , L 2 . In doing so, the base potential of transistor Q 1 falls, and the transistor Q 1 therefore also turns off.
[0034] The magnitude of the overcurrent necessary for the breaker circuit 70 to operate depends on the resistance of resistor R 23 , Zener voltage of Zener diode D 20 , and reverse bias voltage across the base and emitter in order to turn the transistor Q 2 off, etc.
[0035] When an overvoltage is applied across the subscriber lines L 1 , L 2 when off-hook, the breaker circuit 70 operates as described above, and the transistor Q 1 is made to turn off. However, when off-hook, the terminal HC is controlled to be a high potential by the microcomputer (not shown), and the base potential of the transistor Q 2 rises immediately. When the voltage across the base and emitter of the transistor Q 2 exceeds the threshold voltage, the transistor Q 2 is turned on again. As a result, the base potential of transistor Q 1 rises, and the transistor Q 1 is therefore also turned on again. In this way, the transistor Q 1 has self-returning function. When the transistor Q 1 turns on again due to this self-returning function, in the event that an overvoltage is applied across the subscriber lines L 1 , L 2 as before, the breaker circuit 70 operates as described above, and the transistor Q 1 is turned off. In this way, in the event that overvoltages are successively applied across the subscriber lines L 1 , L 2 , the transistor Q 1 repeatedly alternates between a state of being turned on and a state of being turned off.
[0036] FIG. 2 shows the change in time of voltage VBE across the base and emitter of transistor Q 2 .
[0037] At time t 1 , when an overvoltage is applied across the subscriber lines L 1 , L 2 , the breaker circuit 70 operates and the transistor Q 2 is made to turn off. However, in an off-hook state, the potential of terminal HC is controlled to a high potential. The voltage VBE across the base and emitter of transistor Q 2 therefore immediately rises, and the voltage VBE reaches the threshold voltage VT at the time t 2 . In doing so, the transistor Q 2 is turned on again. As an overvoltage is then applied continuously across the subscriber lines L 1 , L 2 , the breaker circuit 70 operates the instant the transistor Q 2 is turned on, and the transistor Q 2 is turned off. After this, the voltage VBE across the base and emitter of transistor Q 2 rises immediately, and the voltage VBE reaches the threshold voltage VT at time t 3 . In doing so, the transistor Q 2 is turned on again. As an overvoltage is then applied continuously across the subscriber lines L 1 , L 2 , the breaker circuit 70 operates the instant the transistor Q 2 is turned on, and the transistor Q 2 is turned off. The same operation is then repeated at time t 4 .
[0038] A period T where the transistor returns to being on from being turned off due to its self-returning function is determined by the size of the overvoltage applied across the subscriber lines L 1 , L 2 and the time constant of the RC circuit (circuit containing resistor R 24 and capacitor C 21 ) connected to the base terminal B 2 of the transistor Q 2 . The period the transistor Q 1 is disconnected for is longer for a larger overvoltage applied across the subscriber lines L 1 , L 2 and thermal fracturing due to collector loss of transistor Q 1 can be suppressed.
[0039] Next, a description is given of the results of this embodiment while referring to FIG. 3 to FIG. 5 .
[0040] FIG. 3 shows a waveform for a surge voltage applied across subscriber lines L 1 , L 2 . In the same drawing, the horizontal axis shows time, and the vertical axis shows voltage.
[0041] FIG. 4 shows a waveform for current passing through transistor Q 1 when the surge voltage shown in FIG. 3 is applied across subscriber lines L 1 , L 2 at the telephone interface of the related art. In the same drawing, the horizontal axis shows time, and the vertical axis shows current.
[0042] FIG. 5 shows a waveform for current passing through transistor Q 1 when the surge voltage shown in FIG. 3 is applied across subscriber lines L 1 , L 2 at the telephone interface 10 of this embodiment. In the same drawing, the horizontal axis shows time, and the vertical axis shows current. In this drawing, the transistor Q 1 repeatedly alternates between being turned on and being turned off, with it being shown that the period the transistor Q 1 is disconnected for is longer for a larger overvoltage.
[0043] As described above, according to the telephone interface circuit 10 of this embodiment, it is possible to turn off the transistor Q 1 the instant an overvoltage is applied across the subscriber lines L 1 , L 2 , and it is possible for the transistor Q 1 to be restored by a self-returning function. In particular, it is possible for the period the transistor Q 1 is disconnected for to be longer for a larger overvoltage applied across the subscriber lines L 1 , L 2 and for thermal fracturing due to collector loss of transistor Q 1 to be suppressed. | A telephone interface circuit comprises a first transistor for controlling opening and closing between a speech circuit and subscriber lines, a second transistor for controlling the first transistor to turn on and off, a positive feedback circuit connecting a collector terminal of the first transistor and a base terminal of the second transistor, an overcurrent detection circuit detecting overcurrent applied to the subscriber lines, and a breaker circuit for turning off the first transistor by lowering the base potential of the second transistor to a low potential when overcurrent is detected at the overcurrent detection circuit. Here, the base terminal of the first transistor and a collector terminal of the second transistor are connected. Further, when off-hook, the base potential of the second transistor is controlled in such a manner as to become a high potential by a microcomputer. | 7 |
FIELD OF THE INVENTION
The present invention relates to a water proof tinder storage container and, more particularly, to a water proof tinder storage container that uses solar power to ignite fire starting tinder positioned on a tinder holder arm.
BACKGROUND OF THE INVENTION
Tinder storage containers and fire starters have been used in many different environments and can be particularly useful during survival situations, camping, and other outdoors activities where people are often isolated from civilization and the conveniences often found in populated environments. Tinder containers, and more particular, water proof tinder containers, are small pocket sized containers that allow the user to store and carry small amounts of dry fire starting tinder in one's pocket or backpack. The stored dry fire starting tinder can be used to start a seed fire that can then be used to ignite larger more difficult fire starting materials often found in the wilderness or other environments. Tinder containers are very useful in survival situations where many times wild tinder is damp or wet from rain, fog, or dew, and cannot be easily ignited. In addition, many outdoors activities take place in and around bodies of water and a water proof portable tinder container protects the dry fire starting tinder from becoming wet if the user should accidentally fall in a body of water. Generally speaking tinder containers of all types are simply water proof containers made from metal or plastic that often include an o-ring seal and are able to keep fire starting tinder dry in wet or damp environments. Tinder containers are often used along side stand-alone fire starters that are also very useful during survival situations, camping, and other outdoors activities. Fire starters can be used to provide warmth, cook meals, and also to signal rescue personnel. Fire starters on the market today use a variety of ignition sources that include, matches, lighters (that use some type of combustible liquid or gas), electrically heated elements, or pyrophoric elements, such as ferrocerium rods that are struck with sharp objects to produce a plurality of sparks. Matches, including water proof matches, do not work well in windy conditions, and provide minimum ignition time. Lighters use pyrophoric elements to ignite the on-board fuel source. Both lighters, and stand-alone pyrophoric type fire starters, all include elements that wear out over time, are susceptible to rapid oxidation in wet environments, are brittle and easily broken, require some means to scrape the pyrophoric element to obtain sparks, can be difficult to use, and contain rare earth elements, such as cerium that are becoming too expensive to be practical. Fire starters that use electrically heated elements require batteries or other electrical sources that wear out and must be replaced or recharged. There are also fire starters that include a tinder storage container portion of the device, but again, the fire starting elements within these devices all use consumable, replaceable, or rechargeable fire ignition systems. Both tinder containers and fire starters can also be life saving devices in a survival situation caused by natural disasters such as hurricanes, tornadoes, and floods. Often times in such natural disasters electrical service is lost and people must leave their homes and fend for themselves. Having dry fire starting tinder in a water proof tinder container and a fire starter to start the dry tinder could save or improve the quality of lives. Ever since tinder containers and fire starters have been used there has been a need for one invention that would provide sufficient water proof space to store enough dry fire starting tinder to start a seed fire, be small enough to carry in one's pocket, and would provide a non-consumable, non-electrical fire starting element to be used to ignite combustible materials in one portable, safe, durable device. The present invention addresses the aforementioned problems by using a structural design that is aimed at minimizing the negative effects thus increasing the likelihood that the individual will carry the tinder container solar powered fire starter and realize its benefits.
SUMMARY OF THE INVENTION
In accordance with the present invention, there is provided . . . a tinder storage container solar powered fire starter that includes top and lower housings that when coupled together form a water tight tinder storage cavity of which the inside bottom surface is a machined parabolic reflector that when used in conjunction with a tinder holder arm that securely positions the fire starting tinder at the exact focus of the reflective parabolic surface of the lower housing is able to use solar power to ignite combustible materials. The tinder holder arm is stowed in the top housing during non-use and incorporates a series of light through holes, and flex points that provide maximum efficiency and quick positioning from stow configuration to fire starting configuration. The inside reflective surface of the top housing is a signal mirror and a lanyard hole is provided to prevent loss. An hour glass shaped air escape slot is also included to aid in the coupling of the top and bottom housings and aid during solar alignment.
It would be advantageous to provide a . . . water tight tinder storage container and solar powered fire starter in one device.
It would also be advantageous to provide a . . . tinder storage container solar powered fire starter that included a reflective parabolic surface as the bottom surface of the tinder storage cavity.
It would further be advantageous to provide a . . . tinder storage container solar powered fire starter that included a tinder holder arm that positioned the tinder at the exact focus of a reflective parabolic surface of the bottom housing.
It would also be advantageous to provide a . . . tinder storage container solar powered fire starter that included a tinder holder arm that could securely hold the tinder in place during use.
It would further be advantageous to provide . . . a tinder storage container solar powered fire starter that included a tinder arm with light through holes and flex points.
It would also be advantageous to provide . . . a tinder storage container solar powered fire starter that included a tinder arm that would allow quick a change of configurations.
It would further be advantageous to provide . . . a tinder storage container solar powered fire starter that included a fire starting element that is non-consumable.
It would also be advantageous to provide . . . a tinder storage container solar powered fire starter that included mounting connectors for a tinder holder arm in all configurations.
It further be advantageous to provide . . . a tinder storage container solar powered fire starter that included a signal mirror.
It would also be advantageous to provide . . . a tinder storage container solar powered fire starter that included a lanyard hole.
It would further be advantageous to provide . . . a tinder storage container solar powered fire starter that provided an hour glass air escape slot to aid in coupling.
It would also be advantageous to provide . . . a tinder storage container solar powered fire starter that is compact enough to carry on one's pocket.
It would further be advantageous to provide . . . a tinder storage container solar powered fire starter that included-a water proof o-ring seal.
It would also be advantageous to provide . . . a tinder storage container solar powered fire starter that included knurled outside surfaces.
BRIEF DESCRIPTION OF THE DRAWINGS
A complete understanding of the present invention may be obtained by reference to the accompanying drawings, when considered in conjunction with the subsequent, detailed description, in which:
FIG. 1 is a perspective view of a tinder storage container solar powered fire starter with top housing removed and tinder holder arm in stowed configuration;
FIG. 2 is a left perspective view of a tinder storage container solar powered fire starter with top housing removed and tinder arm in fire starting configuration;
FIG. 3 is a perspective view of a tinder storage container solar powered fire starter in fire starting configuration with tinder held in position at the exact focus of the reflective parabolic surface of the lower housing using the tinder holder arm; and
FIG. 4 is a front sectional view of a tinder storage container solo powered fire starter in stowed configuration showing stored tinder in place.
For purposes of clarity and brevity, like elements and components will bear the same designations and numbering throughout the Figures.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 is a perspective view of the tinder storage container solar powered fire starter 10 with top housing 34 removed and tinder holder arm 38 in stowed configuration.
FIG. 2 is a left perspective tinder storage container solar powered fire starter 10 with top housing 34 removed and tinder arm in fire starting configuration.
FIG. 3 is a perspective view of the tinder storage container solar powered fire starter 10 in fire starting configuration with tinder held in position at the exact focus of the reflective parabolic inside surface 14 of the lower housing using the tinder holder arm 38 .
FIG. 4 is a front sectional view of the tinder storage container solar powered fire starter 10 in stowed configuration showing stored tinder in place.
Referring to FIGS. 1 to 4 each element of the tinder storage container solar powered fire starter 10 is briefly described. A full description of the function and operation of the tinder storage container solar powered fire starter 10 will follow. The tinder storage container solar powered fire starter 10 of the invention includes, a bottom housing 12 that includes a machined reflective parabolic inside surface 14 , that also functions as the bottom inside surface of the tinder storage cavity 54 . The bottom housing 12 also includes a tinder holder arm male connector 16 , an o-ring channel 56 in which an o-ring seal 22 is exteriorly encircling the entire bottom housing 12 . The bottom housing 12 also includes an air hour glass shaped air escape slot 32 , a lanyard hole 30 , and a knurled lower edge 28 . The tinder storage container solar powered fire starter 10 of the invention also includes a top housing 34 , that has a knurled outside edge 36 around the entire perimeter and can be removeably coupled to the bottom housing 12 . The top housing 34 also includes a tinder holder arm male connector top 40 , an inside flat reflective surface top 52 that also functions as the top inside surface of the tinder storage cavity 54 . The tinder storage container solar powered fire starter 10 of the invention also includes a tinder holder arm 38 , that includes, a female vertical position connector 50 , a female horizontal position stow connector hole 44 , a light through hole tinder wedge upper 46 , light through hole flex point lower 48 , and female connector slot 42 .
In operation and referring to FIG. 4 , the tinder storage container solar powered fire starter 10 is shown in the stowed configuration with the fire starting tinder 18 securely stowed in a water tight environment and the tinder holder arm 38 securely stowed in the top housing 34 . Now referring to FIGS. 1 to 4 , in the stowed configuration, the tinder holder arm 38 is securely stowed in the top housing 34 by aligning the tinder holder arm 38 female horizontal position stow connector hole 44 over the tinder holder arm male connector top 40 and then pressing down and sliding the tinder holder arm 38 away from the center of the top housing 34 allowing the female connector slot 42 to ride underneath the larger diameter top of the tinder holder arm male connector top 40 and along the lower smaller diameter of the tinder holder arm male connector top 40 . This keeps the tinder holder arm 38 securely stowed in the optimum position during non-use. In operation, the tinder holder arm 38 must be removed from the stowed position and repositioned to the fire starting configuration. To remove the tinder holder arm 38 from the stowed position, the user simply slides the tinder holder arm 38 horizontally and towards the center of the top housing 34 using the female connector slot 42 until it stops. This aligns the female horizontal position stow connector hole 44 with the larger diameter top portion of the tinder holder arm male connector top 40 allowing the user to slide the tinder holder arm 38 straight up and over the tinder holder arm male connector top 40 . Once the tinder holder arm 38 is removed from the stowed position, the user must reposition the tinder holder arm 38 in the fire starting configuration. This is accomplished by aligning the female vertical position connector 50 of the tinder holder arm 38 over the tinder holder arm male connector 16 found at the center bottom of the reflective parabolic inside surface 14 of the bottom housing 12 . The user then simply presses straight down causing the female vertical position connector 50 of the tinder holder arm 38 to flex and expand via light through hole flex point lower 48 and slidably and securely connect the tinder holder arm 38 to the tinder holder arm male connector 16 of the center bottom of the reflective parabolic inside surface 14 of the bottom housing 12 . The tinder storage container solar powered fire starter 10 is now in fire starting configuration as shown in FIG. 2 and FIG. 3 . Once the tinder storage container solar powered fire starter 10 is in fire starting configuration, the tinder holder arm 38 allows the user to securely position the fire starting tinder 18 at the exact focus point of the reflective parabolic inside surface 14 of the bottom housing 12 . In addition, the tinder holder arm 38 includes light through hole tinder wedge upper 46 and light through hole flex point lower 48 that minimize light interference once the tinder holder arm 38 is in position allowing maximum efficiency. The light through hole tinder wedge upper 46 and light through hole flex point lower 48 also allow flexing of the tinder holder arm 38 that aids in both changing configurations and holding fire starting tinder 18 in position. Now referring to FIG. 3 , next the user securely wedges a small amount of fire starting tinder 18 into the tinder hole 58 of the tinder holder arm 38 of the tinder storage container solar powered fire starter 10 . This is accomplished by first placing the fire starting tinder 18 into the tinder hole 58 and sliding it towards the light through hole tinder wedge upper 46 . This causes the tinder holder arm 38 to expand via light through hole tinder wedge upper 46 thus wedging the fire starting tinder 18 in place. Now referring to FIG. 3 , the user next aims the tinder storage container solar powered fire starter 10 bottom housing 12 , towards the sun or any nearby star if one is on a space mission. Because the tinder holder arm 38 positions the fire starting tinder 18 at the exact focus of the reflective parabolic inside surface 14 of the tinder storage container solar powered fire starter 10 all photons from the sun striking the reflective parabolic inside surface 14 of the bottom housing 12 of the tinder storage container solar powered fire starter 10 are reflected to a singular focus point at the position of the tinder instantly resulting in extremely high temperatures that are capable of igniting the fire starting tinder 18 . Any type of fire starting tinder 18 could be used with the present invention, wild or man-made. Once the base of the fire starting tinder 18 has been ignited to a burning ember the user grasps the yet unburned top portion of the fire starting tinder 18 and unwedges the fire starting tinder 18 from the tinder hole 58 and flexed light through hole tinder wedge upper 46 and then transfers the burning ember to a larger pile of fire starting tinder 18 placed within a fire pit or suitably prepared area. The inside flat reflective surface top 52 of the tinder storage container solar powered fire starter 10 also serves as a very effective signal mirror to be used to alert rescue personnel in times of emergency. The reflective parabolic inside surface 14 of the bottom housing 12 cannot be used for signaling purposes as all photons are focused to a singular point just above the bottom housing 12 not into space. When coupling the top housing 34 to the bottom housing 12 during non-use a water proof and air tight seal is formed between the top housing 34 and an o-ring seal 22 that is exteriorly encircling the entire bottom housing 12 . Because of this air tight seal, it is necessary to provide a means for a small amount of air trapped during coupling to escape the inside of the storage cavity to prevent the air pocket from preventing the top housing 34 and bottom housing 12 from completely coupling. This is accomplished by the use of an hour glass shaped air escape slot 32 that is shallow at is lower center portion and allows enough air to escape during initial coupling of the top housing 34 and bottom housing 12 to prevent the formation of an air pocket. The o-ring is automatically sealed as the o-ring is pressed further into the lower narrowest shallow portion of the hour glass shaped air escape slot 32 as coupling is completed. The hour glass shaped air escape slot 32 also serves as an aid to aiming the tinder storage container solar powered fire starter 10 directly at the sun by allowing the user to track the shadowing that forms within the hour glass shaped air escape slot 32 when misaligned with the sun. The tinder storage container solar powered fire starter 10 also includes a lanyard hole 30 that allows the user to carry the tinder storage container solar powered fire starter 10 on their belt or secure to back packs or other equipment to prevent loss.
Since other modifications and changes varied to fit particular operating requirements and environments will be apparent to those skilled in the art, the invention is not considered limited to the example chosen for purposes of disclosure, and covers all changes and modifications which do not constitute departures from the true spirit and scope of this invention.
Having thus described the invention, what is desired to be protected by Letters Patent is presented in the subsequently appended claims. | A tinder storage container solar powered fire starter that includes top and lower housings that when coupled together form a water tight tinder storage cavity of which the inside bottom surface is a machined parabolic reflector that when used in conjunction with a tinder holder arm that securely positions the fire starting tinder at the exact focus of the reflective parabolic surface of the lower housing is able to use solar power to ignite combustible materials. The tinder holder arm is stowed in the top housing during non-use and incorporates a series of light through holes, and flex points, that provide maximum efficiency and quick positioning from stow configuration to fire starting configuration. The inside reflective inside surface of the top housing is a signal mirror, a lanyard hole is provided to prevent loss. An hour glass shaped air escape slot provides easy coupling of the top and bottom housings. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention pertains to handling sheets of paper, and more particularly to apparatus and methods for sealing a folded sheet of paper to itself.
2. Description of the Prior Art
Numerous types of business forms have been developed over the years. Many kinds of business forms are used as mailers. An example of a multi-page mailer type business form may be seen in U.S. Pat. No. 5,167,739.
Business forms are usually constructed as sheets of paper having patterns of pressure sensitive adhesive applied to one surface. The sheets are folded in a desired manner by a folding machine such that certain portions of the sheet come into facing contact with the adhesive. The folded sheets are then pressed together, which causes them to adhere to each other along the patterns of adhesive.
Prior equipment for pressing folded sheets together include the reversing machines of U.S. Pat. Nos. 5,133,828; 5,290,385; and 5,300,177. In those machines, a force biases one or more rollers into contact with mating rollers. A folded sheet is fed in a first direction into a roller nip until the sheet had almost completely passed through the nip. Then the rollers are reversed to drive the sheet through the nip again in the opposite direction. The biasing force is strong enough to activate the adhesive and thus create a finished business form.
A primary disadvantage of the machines of the foregoing patents is the noise produced by the contacting rollers when no folded sheets are in the nips. Another disadvantage is that the finished forms leave the machines at the same locations that they entered the machines. Consequently, second folded sheets cannot be fed to the nips until the previous forms have been discharged and removed from the nips.
U.S. Pat. No. 5,169,489 shows a pressure sealer system having four nips, two at one level and two at a higher level. The rollers of each nip are pressed together by spring biasing devices. Folded sheets are fed in a first direction between the two lower nips. Thereafter, the folded sheets pass to a higher elevation and reverse direction to pass through the two higher nips. Because of the four nip and reversing construction, the machine of the U.S. Pat. No. 5,169,489 is quite complicated as well as undesirably noisy. In addition, the reversing direction of the folded sheets complicates both the feeding of the folded sheets into the machine and the removal of the completed business forms from the machine.
U.S. Pat. No. 5,183,527 describes a seal module in which one roller of a nip is spring biased to be non-parallel to another roller when no form is present. When a form is fed to the nip, the form forces the rollers against the force of the spring into a parallel relationship. The forms travel in one direction in the downstream direction through the seal module. There is no adjustment for the linear distance between the rollers, thus limiting the versatility of the seal module. In addition, initial setup of the seal module can be rather tricky.
U.S. Pat. No. 5,397,427 discloses a pressure seal system in which two rollers of a nip are pressed into contact with each other by a biasing force. Forms passing through the nip are acted on by the biasing force but spread the rollers apart as they pass through the nip. The forms pass in one direction through the pressure sealer. The amount of noise as well as the wear on the rollers are important disadvantages of the seal system of the U.S. Pat. No. 5,397,427.
Thus, a need exists for improvements in machines that seal folded business forms.
SUMMARY OF THE INVENTION
In accordance with the present invention, an in-line pressure sealer is provided that produces forms in a simpler, quieter, and more efficient manner than was previously possible. This is accomplished by apparatus that includes two pairs of rollers that are biased away from each other to adjustable but positively maintained distances between them.
One pair of rollers, consisting of first and second rollers, serve as input rollers that form an infeed nip. The other pair of rollers, consisting of third and fourth rollers, form an outfeed nip. Each roller is mounted at its opposite ends for rotation in respective blocks. The blocks are received in a frame. According to one aspect of the invention, the blocks of the infeed rollers are received in first slots in the frame, and the outfeed roller blocks are received in second slots in the frame.
The blocks of the first and third rollers are stationarily located against ends of the associated frame slots. The blocks of the second and fourth rollers are free to slide in the frame slots. Springs bias the blocks of the second and fourth rollers away from the blocks of the first and third rollers. Positive stops limit the motions of the blocks of the second and fourth rollers and thus the clearances between the infeed rollers and the outfeed rollers. The locations of the positive stops for the infeed and outfeed rollers are independently adjustable relative to the frame.
An infeed roller is driven by a conventional electric motor, suitable pulleys, and a belt. An outfeed roller is driven by the driven infeed roller. In turn, the driven outfeed roller drives the other infeed and outfeed rollers. A folded sheet fed in a downstream direction to the infeed nip is propelled through that nip in the same downstream direction to the outfeed nip. The outfeed nip discharges a completed form from the pressure sealer in the same downstream direction as the folded sheet was fed to the infeed nip.
The clearances between the infeed and outfeed rollers are set to suit a particular folded sheet and strips of pressure sensitive adhesive applied to the sheet. For example, the clearance of the infeed rollers can be set to burst the bubbles of the pressure sensitive adhesive. The clearance of the outfeed rollers can then be set to activate the adhesive such that the facing portions of the folded sheet adhere to each other along the adhesive strips. As a result, a completed and properly sealed form is discharged from the outfeed rollers.
Because the rollers never touch, operation of the invention is very quiet. Further, since the springs maintain the clearances between the rollers when no forms are present, the non-contacting nature of the rollers precludes the possibility that they can produce wear on each other.
To guide the folded sheets to the infeed and outfeed nips, the in-line pressure sealer further comprises a pair of cross-pieces that are joined to the frame. One cross-piece is located a short distance upstream of the infeed nip, and the second cross-piece is located between the two nips. The cross-pieces have respective flat surfaces that are coplanar with each other and with a plane that extends between the two nips. The folded sheets are guided to the infeed nips by the first cross-piece, and the second cross-piece guides the folded sheets from the infeed nip to the outfeed nip.
The method and apparatus of the invention, using pairs of non-contacting rollers having adjustably fixed clearances therebetween, thus discharges completed forms from the outfeed nip in the same direction as folded sheets are fed to the infeed nip. The clearances between the rollers of each pair can be adjusted independently of each other to suit different sheet stocks and adhesives.
Other advantages, benefits, and features of the present invention will become apparent to those skilled in the art upon reading the detailed description of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partially broken top view of the invention.
FIG. 2 is a cross sectional view taken along line 2--2 of FIG. 1.
FIG. 3 is a cross sectional view on an enlarged scale taken along line 3--3 of FIG. 1 and rotated 90 degrees counterclockwise.
FIG. 4 is a cross sectional view on an enlarged scale taken along line 4--4 of FIG. 1.
FIG. 5 is a perspective view of a typical sheet with strips of pressure sensitive adhesive applied thereto that can be processed into a completed business form by the present invention.
FIG. 6 is a front view of the sheet of FIG. 5 folded into a Z fold.
FIG. 7 is a top view of FIG. 6.
FIG. 8 is an end view of a completed business form processed by the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Although the disclosure hereof is detailed and exact to enable those skilled in the art to practice the invention, the physical embodiments herein disclosed merely exemplify the invention, which may be embodied in other specific structure. The scope of the invention is defined in the claims appended hereto.
Referring first to FIGS. 1-4, an in-line pressure sealer 1 is illustrated that includes the present invention. The in-line pressure sealer 1 is particularly useful for sealing folded sheets of paper into completed business forms, but it will be understood that the invention is not limited to form processing applications.
The in-line pressure sealer 1 is located downstream from a conventional folding machine 7. I have found that a model D-590 Auto-Folder machine manufactured by Duplo U.S.A. Corporation of Santa Ana, Calif., works very well with the in-line pressure sealer. In the folding machine 7, sheets of paper having preselected patterns of pressure sensitive adhesive applied to one or both surfaces are folded along desired fold lines. By way of example, FIG. 5 shows a sheet of paper 9 having four strips 11, 14 and 12, 13 of pressure sensitive adhesive applied to opposite surfaces 15 and 17, respectively, along the sheet edges 19 and 21. Although not shown, similar strips of pressure sensitive adhesive can also be applied along the sheet edges 20 and 22. In the folding machine, the sheet 9 is folded along fold lines 23 and 25 into a Z folded sheet 3, FIGS. 6 and 7. The folded sheet 3 is fed in the downstream direction 27, FIG. 1, by belts, not shown, on the folding machine to the in-line pressure sealer 1. The downstream direction 27 relative to the folded sheet is in the direction of arrow 27' in FIG. 7.
In the construction illustrated in FIGS. 1-4, the in-line pressure sealer 1 is comprised of a frame 29 that includes a base plate 33. The base plate 33 is attached in any convenient manner to the folding machine 7. Secured to the base plate by conventional fasteners 34 are a pair of parallel channels 35. Two vertically oriented side plates 37 rest on the base plate and are fastened each to a channel 35 by fasteners 38. There is a side cover 39 mounted by means of a main panel 40 to each channel on the opposite side thereof as the corresponding side plate 37. The side covers 39 are held in place by fasteners 42. Each side cover has a short bent-over panel 41 that is screwed to the end of an associated side plate by fasteners 44. An L-shaped top cover 43 rests on and extends between the short panels 41 and bent-over top tabs 45 of the side covers.
Each side plate 37 is fabricated with first and second vertically oriented slots 47 and 49, respectively, extending from the side plate top surface 51. Slidingly received in the first slot 47 of each side plate are upper and lower infeed bearing blocks 53 and 55, respectively. Both infeed bearing blocks 53 and 55 have oppositely extending flanges 57 and 59, respectively, thereby giving the bearing blocks a T-shaped cross section (FIG. 1). There is a bore 61 through each upper infeed bearing block, and a similar bore 63 extends through each lower infeed bearing block. Similar outfeed bearing blocks 65 and 67 are received in the slots 49 of each side plate. The upper outfeed bearing blocks 65 have respective flanges 69 and bores 71; the lower outfeed bearing blocks 67 have similar flanges and bores. A cap 77 is mounted by screws 79 to the top surface 51 of each side plate. The bearing block flanges 57, 59, and 69 guide the bearing blocks in the side plate slots 47 and 49.
Interposed between the upper and lower infeed bearing blocks 53 and 55, respectively, in each side plate 37 is a compression spring 81. Similar springs 83 are located between the outfeed bearing blocks 65 and 67. The springs 81 and 83 fit within counterbores 84 in the bearing blocks. Adjusting bolts 85 and 87 are threaded into each cap 77 and bear against associated upper infeed and outfeed bearing blocks 53 and 65, respectively.
The adjusting bolts 85 and 87 and the springs 81 and 83 cooperate to locate the bearing blocks 53, 55 and 65, 67 relative to each other. Specifically, the springs 81 bias the infeed bearing blocks away from each other. The end surfaces 89 of the first side plate slots 47 contact the lower infeed bearing blocks and locate them at fixed locations. The adjusting bolts 85 locate the upper bearing blocks 53. By adjusting the adjusting bolts 85, the locations of the upper bearing blocks relative to the lower bearing blocks is adjusted. Consequently, the center distance between the bores 61 and 63 is also adjusted by the adjusting bolts 85. The identical situation occurs for the outfeed bearing blocks 65 and 67, the springs 83, and the adjusting bolts 87.
Rotatably mounted in the bores 61 of the two upper infeed bearing blocks 53 by means of roller bearings 89 is an upper infeed roller 91. Similarly, there is a lower infeed roller 93 between the bearing blocks 55, an upper outfeed roller 95 between the bearing blocks 65, and a lower outfeed roller 97 between the bearing blocks 67. The upper and lower infeed rollers 91 and 93, respectively, cooperate to form an infeed nip. The upper and lower outfeed rollers 95 and 97, respectively, cooperate to form an outfeed nip. The clearance between the infeed rollers is set by adjusting the adjusting bolts 85; the clearance between the outfeed rollers is set by adjusting the adjusting bolts 87.
The in-line pressure sealer 1 also includes a pair of cross-pieces 99 and 101. Both cross-pieces 99 and 101 extend between and are joined to the side plates 37 by means of right angle tabs 102 and screws 105. The cross-pieces have respective horizontal surfaces 103 that are located generally coplanar with each other and generally coplanar with a plane extending between the infeed and outfeed nips. The cross-piece 99 is located on the upstream side of the infeed nip, and the cross-piece 101 is located between the infeed and outfeed nips.
To rotate the rollers 91, 93, 95, and 97, the in-line pressure sealer 1 further includes an electric motor 106. A suitable motor is a 1/6 horsepower motor manufactured by Minneapolis Electronic Technology of Minneapolis, Minn. In the preferred embodiment, the motor 106 is fixed to the underside of the base plate 33 by means of motor feet 108 and screws 110. There is a drive pulley 107 on the motor shaft 109. A similar driven pulley 111 is connected to one end 112 of the lower infeed roller 93. An infeed belt 113 is trained over the pulleys 107 and 111. Connected to the second end 115 of the lower infeed roller is a pulley 117; a similar pulley 119 is connected to the lower outfeed roller 97. An outfeed belt 121 is trained over the pulleys 117 and 119.
Also connected to the lower outfeed roller 97 adjacent the pulley 119 is another pulley 122. There is a similar pulley 124 on the upper infeed roller 91. A first idler pulley 125 is rotatably mounted on a stub shaft 127 that is threaded or otherwise held in the side plate 37 between the slots 47 and 49. A second idler pulley 129 is rotatably mounted on a stub shaft 131 threaded into the side plate between the slot 47 and the folding machine 7. A long double sided timing belt 133 is trained over the pulleys 122, 124, 125, and 129, as best shown in FIG. 2. At the opposite end of the upper infeed roller 91 as the pulley 124 is a pulley 135. The corresponding end of the upper outfeed roller 95 also has a pulley 137. A timing belt 139 is trained over the pulleys 135 and 137. Accordingly, energization of the motor 106 causes rotation of all the rollers 91, 93, 95, and 97.
In operation, the clearances between the infeed rollers 91, 93 and the outfeed rollers 95, 97 are set by the adjusting bolts 85 and 87 to suit the particular folded sheet 3 and adhesive strips 11 and 13 that are to be processed into a completed business form. Specifically, the clearance between the infeed rollers is set at a sufficiently close spacing so as to actuate the pressure sensitive adhesive on the folded sheet. The clearance between the outfeed rollers is set to cause adhesion of the activated adhesive to the facing portion of the folded sheet. For clarity, the clearances of the nips are shown greatly exaggerated in the drawings.
As a typical example, the clearance between the infeed rollers is set at 0.004 inches, and the clearance between the outfeed rollers is set at 0.001 inches. Those settings are made by adjusting the adjusting bolts 85 and 87. The springs 81 and 83 hold the rollers 91, 93 and 95, 97, respectively, apart at the clearances set by the adjusting bolts. Jam nuts 123 on the adjusting bolts maintain the desired settings. Because of the springs, the two infeed rollers never touch each other, nor do the outfeed rollers touch each other.
When electrical power is applied to the motor 106, the rollers 91, 93, 95, and 97 rotate together at the same speed. Due to the nip clearances made possible by the adjusting bolts 85 and 87 and the springs 81 and 83, the operation of the in-line pressure sealer 1 is very quiet. Further, the lack of roller contact at the nips eliminates wear of the rollers due to each other and also eliminates roller expansion from heat.
Folded sheets 3 are continuously fed by the folding machine 7 in the downstream direction 27 to the in-line pressure sealer 1. The folding machine belts deposit the folded sheets onto the cross-piece 101, which guides the folded sheet leading edge to the infeed nip. The small clearance between the infeed rollers 91 and 93 causes the folded sheet to be simultaneously propelled downstream and squeezed between the infeed rollers to activate the pressure sensitive adhesive on the folded sheet. The leading edge of the folded sheet is guided by the cross-piece 103 to the outfeed nip. The operation of the outfeed rollers is substantially similar to that of the infeed rollers to complete the process of adhering the folded sheet to itself and produce a completed business form. The in-line pressure sealer can accept and process the folded sheets at the same rate they are fed to it by the folding machine. The business forms emerge from the outfeed nip in the downstream direction 27. From the in-line pressure sealer, the business forms are collected by known equipment for further handling.
In summary, the results and advantages of business forms can now be more fully realized. The in-line pressure sealer 1 provides both the force to seal sheets 3 that are folded by a folding machine 7 and the ability to handle folded sheets and adhesive strips of different thicknesses. This desirable result comes from using the combined functions of the adjusting bolts 85 and 87 and the springs 81 and 83. The springs bias the infeed bearing blocks 53, 55 and the outfeed bearing blocks 65, 67 away from each other to positive stops adjustably set by the adjusting bolts. The adjusting bolts are set to suit a particular folded sheet and adhesive strip, but the springs maintain the desired nip clearances even when no folded sheet is present. As a result, the infeed rollers 91, 93 and the outfeed rollers 95, 97 never contact each other. The result is a very quiet and long lasting machine that can maintain the production rates of the folding machine.
It will also be recognized that in addition to the superior performance of the in-line pressure sealer 1, its construction is such as to cost no more than traditional pressure sealing machines. Also, since it is made of rugged components having a simple design, and since the rollers never contact each other during operation, the need for maintenance is minimal.
Thus, it is apparent that there has been provided, in accordance with the invention, an in-line pressure sealer that fully satisfies the aims and advantages set forth above. While the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, it is intended to embrace all such alternatives, modifications, and variations as fall within the spirit and broad scope of the appended claims. | An in-line pressure sealer processes folded sheets with pressure sensitive adhesive into finished business forms. The in-line pressure sealer has pairs of infeed and outfeed rollers, each with a predetermined clearance therebetween. The clearances are adjustably set by means of screws coacting with a frame and with bearing blocks that rotatably mount the rollers. The infeed and outfeed clearances are adjustable independently of each other. The rollers of each pair are biased away from each other to maintain the clearances when no form is present between the rollers. The folded sheets are guided to the infeed rollers by a first cross-piece and to the outfeed rollers by a second cross-piece. A motor, acting through suitable pulleys and belts, drives the infeed and outfeed rollers. | 8 |
FIELD OF THE INVENTION
The invention pertains to the field of surface processing of materials and in particular to the use of plasmas in surface processing of materials
BACKGROUND OF THE INVENTION
The matter of preparing a surface for further processing is an integral step in many industrial processes, and a vast array of methods and techniques exist to address this matter. At one extreme of the spectrum there are sophisticated techniques involving advanced ultra-high vacuum and ion-beam equipment to obtain surfaces that are near to atomically perfect, such as those required in the semiconductor industry. At the other extreme, there are macroscopic abrasive techniques such as sanding, which also have their specifically appropriate fields of application.
In the field of paper products a variety of methods have been employed to address the modification of surfaces by the removal of outer layers, for example, the removal of all or portions of coatings that may have been applied to a substrate. An example of an application in paper products is the bonding of packaging materials that have already been printed. In order to fold and glue the packaging, sections of printed area need to be removed and the surface prepared for good adhesion. In this kind of industrial field abrasion (for example, sanding), chemical treatment, and corona discharge treatment have all found application in one way or another.
Amongst the disadvantages of abrasion is the fact that it is a contact method, exercised by mechanical means. This leads to dust problems and considerable wear and tear on materials, parts and equipment. It is also difficult to control abrasive processes to a degree that allows extremely precise removal of outer surfaces, a feature that may be desirable in applications where it is important not to damage the underlying substrate, or where the application may require the removal in precise patterns or to specific depths. Abrasion is, however, a very direct and low cost method.
Chemical treatment, for its part, tends to be very selective in what it does or does not remove, and its efficacy will depend on the ability of the treatment to interact with the particular materials and surfaces involved. If the treatment involves the wet application of chemicals, there may be wetting problems associated with the process: for instance, when the particular treatment inadequately wets the materials to be removed, or else is absorbed by the underlying substrate, causing unwanted chemical changes or physical deformations (e.g., cockling in the case of paper products). Adsorption of chemical treatments may also leave unwanted residues. Chemical treatment also has associated chemical control and safety considerations, often governed by stringent regulations requiring special control mechanisms.
Corona treatment, while a very elegant physical technique, cannot remove materials to the degree required in many industrial applications and certainly is, for example, not capable of stripping sections of packaging materials prior to automated industrial glue bonding. The same holds for the wider spectrum of glow discharge techniques.
Various techniques based on light have been applied in this field and, while contact-less and highly directable, they tend to be expensive and quite selective about the materials that can be removed. Such techniques most often find application in the very highest technology arenas such as surface photo-preparation of semiconductors. In keeping with the specific requirements of these fields, they are then also often implemented in vacuum. This immediately limits the efficacy of these techniques within a broader base of industry. While high power light sources capable of operating in air at atmospheric pressures are available, they are very expensive.
In the case of surface treatments that can be used on a manufacturing scale, what is required is a non-selective, contact-less technique that does not require a special environment (e.g., a vacuum), and can be used on a wide variety of materials. The method must also be one that can work economically at very high speeds while still being directable in order to obtain maximal control over its application.
BRIEF SUMMARY OF THE INVENTION
In accordance with the present invention, a directed plasma beam is employed in air to selectively remove coatings from paper products at high production rates. The shape and intensity of the beam is controlled to obtain a controlled rate of removal of the coating. The method does not require vacuum to be established and allows for the plasma to be generated from high pressure air.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a directed plasma beam employed to selectively remove coatings on a paper-based surface moving at high speed.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 Illustrates the essence of the preferred embodiment of the invention. A plasma beam 1 is generated from a supply of pressurized air 2 by plasma gun 3 . Methods, mechanisms and fixtures to create, shape and direct the plasma beam are well known to those skilled in the art and are neither discussed here nor depicted in FIG. 1 . Plasma beam 1 is directed to the layer 4 on substrate 5 while substrate 5 moves under the plasma beam 1 at high speed. In the packaging industry, these speeds may vary from 1 meter per second to 10 meters per second and more. Under the action of plasma beam 1 , layer 4 is removed from substrate 5 .
The term “plasma” is to be understood herein to include all ionization products of an electrical or electromagnetic discharge in any gas or mixture of gases. In this description, the term “plasma beam” is understood to be a beam consisting of such ionization products. To the extent that the intent with this invention is a use of a beam of intensity greater than that achievable by means of the broad group of techniques, known to those skilled in the art as glow discharge, the term “plasma beam” is understood to be a directional beam, unlike glow discharge mechanisms such as corona treatment.
The term “plasma gun”, in keeping with the foregoing, is understood to be any source of plasma beams. It is also understood that layer 4 may comprise one single layer, but, in the general case of the preferred embodiment, may comprise more than one constituent layer.
The intent of the invention is to provide a method to remove whatever single layer, or combination of layers, is resident on the surface of the substrate 5 . In this respect, the layer or layers may consist of one material or a combination of materials. The invention specifically allows the removal of all of the materials and constituent layers at once.
In order to control the removal of layer 4 from substrate 5 , the beam-shape of plasma beam 1 is controlled, as is the beam-intensity of plasma beam 1 . Mechanisms to establish this control of beam-shape are well known to those skilled in the art and are not discussed further herewith nor are they depicted in FIG. 1 . The beam-intensity of plasma beam 1 may be controlled by controlling the flow of air through the plasma gun 3 and by controlling the power and/or current in the discharge within the plasma gun 3 . Neither of these control mechanisms are depicted in FIG. 1 as they are well known to those skilled in the art. The well-defined and highly direction plasma beam 1 allows selective removal of layer 4 from substrate 51 such as strips used for adhesive bonding, at high rates as all of the energy from the discharge within the plasma gun 3 is concentrated on a small area.
Plasma guns can operate on alternating current or direct current and work well with many different gases. Most commonly, however, they employ argon, nitrogen or air. Since air comprises 80% nitrogen, it is a good choice as candidate gas in which to generate the plasma. To the extent that air contains a major percentage of a reactive gas, oxygen, this may be used to great advantage in some cases. In this preferred embodiment, therefore, air is both the discharge medium for the plasma and the environment in which the plasma beam is to be directed. This combination makes for a method that allows the use of a low cost technology to remove a layer or layers of adherent material from a surface in controlled fashion.
Since both the beam-intensity and the speed of the substrate 5 and layer 4 combination may be independently varied, a combination of intensity and speed can be selected for the optimal removal of layers 4 without burning or charring the substrate 5 .
By way of example, varnished and metalized cardboard materials, used in the packaging industry to make boxes, were cleaned at rates of over 1 meter per second for a 10 millimeter wide strip, including full removal of the aluminum metalization layer, using a pro-cut 25 plasma cutting unit supplied by the lincoln electric company of cleveland, ohio in the united states. | In accordance with the present invention, a directed plasma beam is employed in air to selectively remove coatings from paper products at high production rates. The shape and intensity of the beam is controlled to obtain a controlled rate of removal of the coating. The method does not require vacuum to be established and allows for the plasma to be generated from high pressure air. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a national phase of international application PCT/EP 2012/061296, filed Jun. 14, 2012, which was published on Dec. 20, 2012, as WO 2012/172000, which claims the benefit of European application No. 11170349.2, filed Jun. 17, 2011. The respective contents of each of these applications are incorporated here by reference in the entirety.
FIELD OF THE INVENTION
The present invention relates to cycloserine resistant mutants of lactic acid bacteria characterized by having improved resistance towards ethanol. The cycloserine resistant mutants of lactic acid bacteria can e.g. be used for malolactic fermentations of wine (i.e. including sparkling wine such as Cava/champagne) having high alcohol levels.
BACKGROUND ART
Lactic acid bacteria such as Lactobacillus plantarum and Oenococcus oeni are used in the wine industry for malolactic fermentation. Their functionality is based on the ability to convert malic acid into the gentler lactic acid which is used for many types of wine. Over the last decades, average temperatures have risen noticeably in the wine producing countries leading to ripened grapes with higher sugar content thereby producing wines with higher alcohol. Today many wines have an alcohol content of 14-15% and this is a substantial challenge and stress condition for the fermenting microorganism such as yeast and lactic acid bacteria.
As discussed in U.S. Pat. No. 7,625,745 B2 (Danstar Ferment, CH)—in traditional winemaking, the malolactic fermentation (MLF) is produced by means of the spontaneous growth of an indigenous flora of lactic acid bacteria. The process of MLF begins of its own accord, when the malolactic flora is sufficiently developed, that is to say in a random manner between the end of alcoholic fermentation and several weeks, even several months, after the alcoholic fermentation. When the malolactic bacteria reach a concentration of about 10 6 CFU/ml in the medium, they enter an active metabolic phase and start the fermentation of the malic acid. In these conditions, Oenococcus oeni is the species most frequently responsible for the MLF. In fact, if at the start of alcoholic fermentation a predominance of the homofermentative Lactobacillus plantarum and Lactobacillus casei species is observed, these disappear when the alcohol content increases. After alcoholic fermentation, it is the species Pediococcus and Oenococcus , depending on the pH, which predominate and finally reach the critical concentration to start the MLF.
In short, one may say that natural/wildtype Lactobacillus plantarum strains have a relatively low inherent resistance to the concentrations of ethanol/alcohol present in the grape juice during wine production.
U.S. Pat. No. 7,625,745 B2 (PCT filed 2004 and published in 2009) describes the selection of alcohol-resistant Lactobacillus plantarum lactic acid bacterial strains and it is said that the authors believed that it was unexpected that it was possible to select such alcohol-resistant Lactobacillus plantarum lactic acid bacterial strains—e.g. due to that this resistance to alcohol was hitherto unknown for such the Lactobacillus plantarum strains (see e.g. C4, I. 20-30 and figures of U.S. Pat. No. 7,625,745 B2).
It is here relevant to note that in U.S. Pat. No. 7,625,745 B2 a screening was made of natural Lactobacillus plantarum strains arising from fermented wines (see e.g. Example 1 of U.S. Pat. No. 7,625,745 B2).
The isolates of natural lactic acid bacteria were subjected to a selection pressure of resistance to alcohol levels above 10% and two particular L. plantarum strains were found to be sufficiently resistant to alcohol levels above 10% (see e.g. Example 7 of U.S. Pat. No. 7,625,745 B2).
D-cycloserine (D-4-amino-isoxazolidone) is an antibiotic which inhibits alanine racemase, D-alanyl-D-alanine ligase, D-alanylalanine synthase and D-alanine permease causing cell lysis.
D-alanine racemase is essential for the production of D-alanine, an integral part of the peptidoglycan layer of the cell wall.
Strains of Lactobacillus plantarum in which the alanine racemase gene (air) of Lactococcus lactis has been inserted on a plasmid have resistance to D-cycloserine (Bron et al., 2002 Appl Environ Microbiol. 68:5663-5670).
It is here relevant to note that above discussed article of Bron et al does not in any way relate to identification of Lactobacillus plantarum strains with improved resistance to high concentrations of ethanol.
To the knowledge of the present inventors—there is in the prior art not described or suggested any herein relevant link between increased resistance to D-cycloserine and improved resistance to high concentrations of ethanol.
SUMMARY OF THE INVENTION
The problem to be solved by the present invention is to provide a Lactobacillus plantarum composition with improved resistance towards for wine relatively high concentrations of ethanol.
The Lactobacillus plantarum composition is particularly useful for production of wine.
The solution is based on that the present inventors have developed a novel selection method for the identification of new improved Lactobacillus plantarum compositions.
A novel important step of the herein described new selection method relates to that the present inventors have identified a herein surprisingly relevant link between increased resistance to D-cycloserine and improved resistance to high concentrations of ethanol.
Accordingly, the herein described novel selection method may overall be seen as comprising following two steps:
(i): first to screen/select for Lactobacillus plantarum strains/cells with increased resistance to D-cycloserine—one may term it a resistance to D-cycloserine that are significantly higher than normally present in natural/wildtype Lactobacillus plantarum strains; and (ii): from the pool of D-cycloserine resistant cells identified in step (i) is then screened/selected for a Lactobacillus plantarum strain/cell that has improved resistance to a for wine relatively high concentrations of ethanol.
As shown in working Example 3 herein—the present inventors identified that from a pool of D-cycloserine resistant selected Lactobacillus plantarum strains/cells (i.e. from step (i) above) was it relatively rapid to then screen/select for a Lactobacillus plantarum strain/cell that has improved resistance to relatively high concentrations of ethanol—essentially, the reason for this is that the presents inventors surprisingly identified that a relatively high percentage of the first selected D-cycloserine resistant cells were also resistant to relatively high concentrations of ethanol.
Accordingly, the first screening/selection for increased D-cycloserine resistance may, as discussed herein, be seen as a kind of pre-step to rapidly and efficient be able to screen/select/enrich for a Lactobacillus plantarum strain/cell that has improved resistance ethanol.
As evident to the skilled person—a significant advantage of the herein described screening/selection method is that one relatively rapidly and efficiently is able to screen/select for a Lactobacillus plantarum strain/cell that has improved resistance ethanol.
For instance, if one already has a Lactobacillus plantarum strain with commercial relevant good properties in relation to e.g. malolactic fermentation of wine grape juice—one can then use this strain as a starting cell for mutagenesis and then relatively rapidly select for and thereby get/identify a novel Lactobacillus plantarum strain that has improved resistance to ethanol and still maintains its earlier good properties with respect to e.g. malolactic fermentation of wine grape juice.
As shown in working Example 3 herein—approximately 10% of the first selected D-cycloserine resistant cells were also resistance to relatively high concentrations of ethanol.
To the contrary—as shown in working Example 4 herein—by trying to identify an ethanol resistant cell directly from a pool of individual Lactobacillus plantarum mutant cells, where there had not been made the pre-step of selecting for D-cycloserine resistance, it was not even possible to identify a single ethanol resistant cell.
Accordingly, without using the novel screening/selection method as described herein—it would not (or would take a very long time) be possible to identify an ethanol resistant mutant strain of the Lactobacillus plantarum CHCC14158 starting strain used in working Example 3 herein.
Without being limited to theory—a theoretical explanation for the herein surprisingly identified and discussed link between increased D-cycloserine resistance and increased ethanol resistance could be that such increased D-cycloserine resistant Lactobacillus plantarum cells produce more of the so-called extracellular polysaccharides (EPS). It could then theoretically be that such extracellular polysaccharides (also termed exopolysaccharides) could give a kind of protection around the cell—i.e. that it could be these extracellular polysaccharides that protect the cells against D-cycloserine entry into the cells and thereby give the increased D-cycloserine resistance.
Similar and without being limited to theory—it could then also be these exopolysaccharides that would protect the Lactobacillus plantarum cells in high ethanol environment and thereby give the increased ethanol resistance.
As discussed above, the herein identified Lactobacillus plantarum cells are first selected for increased resistance to D-cycloserine—one may term it as resistance to D-cycloserine that is significantly higher than normally present in natural/wildtype Lactobacillus plantarum strains.
In the prior art document U.S. Pat. No. 7,625,745 B2 as discussed above—there was not made any herein relevant selection for increased resistance to D-cycloserine.
Accordingly, as understood by the skilled person—there is absolutely no reason to believe that any of the Lactobacillus plantarum strains described in U.S. Pat. No. 7,625,745 B2 would have a resistance to D-cycloserine as discussed herein (see e.g. working Example 1 herein, where there is described the herein relevant D-cycloserine resistance assay).
Similar, in other above discussed Bron et al., 2002 article—there was not made any herein relevant selection for increased ethanol resistance.
Accordingly, as understood by the skilled person—there is absolutely no reason to believe that any of the Lactobacillus plantarum strains described in the Bron et al., 2002 article would have an ethanol resistance as discussed herein (see e.g. working Example 2 herein, where there is described the herein relevant ethanol resistance assay).
In summary, it is submitted that the herein relevant discussed Lactobacillus plantarum strains are as such novel strains over the prior art.
Accordingly, a first aspect of the invention relates to a Lactobacillus plantarum composition, which comprises from 10 4 to 10 14 CFU/g Lactobacillus plantarum cells, wherein the Lactobacillus plantarum composition is characterized by that:
(i): the Lactobacillus plantarum cells have an increased resistance to D-cycloserine—defined by that the cells are Lactobacillus plantarum cells, wherein the amount of D-cycloserine that reduces the OD 600 measured growth, after 24 hours growth at 18° C., with 50% in the known Grape Juice GJ-5 medium (GJ-5 medium has the following composition: Grape juice concentrate 70.0 g, Yeast paste 30.0 g. Tween 80 0.5 g, MnSO4H2O 0.1 g and Tap water 900.0 g) as compared to the growth in the GJ-5 medium without D-cycloserine (i.e. with 0 μg/ml D-cycloserine) is higher than 70 μg/ml D-cycloserine;
and
(ii): Lactobacillus plantarum cells have an improved resistance towards ethanol—defined by that the cells are Lactobacillus plantarum cells, wherein the cells can grow to an OD 600 of at least 0.8 after 3 days incubation at 25° C. in the GJ-5 medium with 11% ethanol.
As understood by the skilled person in the present context—the Lactobacillus plantarum composition of the first aspect herein is a composition, wherein
(i): the cells (in point (i) of first aspect) are positively resistant to D-cycloserine in the D-cycloserine resistance assay of example 1; and
(ii): the cells (in point (ii) of first aspect) are positively resistant to ethanol in the ethanol resistance assay of example 2.
Both the D-cycloserine resistance assay [of point (i)] and ethanol resistance assay [of point (ii)] are based on known, commercially available standard elements (such as e.g. standard media etc).
Accordingly, based on the detailed assay description herein (see e.g. example 1 herein for D-cycloserine resistance assay and example 2 herein for ethanol resistance assay) the skilled person is routinely able to repeat these assays to objectively determine whether a specific Lactobacillus plantarum cell of interest complies with the D-cycloserine resistance [of point (i)] and ethanol resistance [of point (ii)] levels of the first aspect of the invention.
The novel Lactobacillus plantarum composition as described herein may preferably be used for wine production. The dose and administration may be done according to the art.
Further, all other herein relevant steps for making a wine may be done according to the art. Such other wine production relevant steps (e.g. use of yeast cells) are well known routine steps for the skilled person and therefore not necessary to discuss in details herein.
Accordingly, a second aspect of the invention relates to a method for producing a wine comprising administering the Lactobacillus plantarum composition of first aspect and herein described related embodiments to a grape juice or wine and performing further adequate steps to make the wine.
A third aspect of the invention relates to a method for screening and isolating a novel Lactobacillus plantarum cell comprising the following steps:
(a): selecting and isolating from a pool of individual Lactobacillus plantarum cells, a new selected pool of Lactobacillus plantarum cells that have increased resistance to D-cycloserine under the conditions of point (i) of first aspect; (b): selecting and isolating—from the selected pool of Lactobacillus plantarum D-cycloserine resistant cells of step (a)—a new isolated Lactobacillus plantarum cell that has improved resistance towards ethanol under the conditions of point (ii) of first aspect.
It is evident to the skilled person that once the inventors herein have disclosed the relevant test assays (i.e. the assays of Examples 1 and 2 herein) it will be routine work for the skilled person to select other new Lactobacillus plantarum cells complying with the criteria of the first aspect herein.
As discussed herein, by using the novel screening/selection method as described herein the inventors have selected and isolated a number of new improved Lactobacillus plantarum cells.
Embodiment of the present invention is described below, by way of examples only.
DEFINITIONS
All definitions of herein relevant terms are in accordance of what would be understood by the skilled person in relation to the herein relevant technical context.
The term “ Lactobacillus plantarum ” is a well know term to the skilled person and the skilled person knows if a particular lactic acid bacterium cell of interest is a Lactobacillus plantarum cell or not.
DRAWINGS
FIG. 1 : In this figure the resistance to D-cycloserine of different Lactobacillus plantarum strains is shown: For further details—see working Examples herein.
DETAILED DESCRIPTION OF THE INVENTION
Lactobacillus plantarum Composition:
The term “ Lactobacillus plantarum composition” shall be understood according to the art. It is herein understood as a Lactobacillus plantarum composition comprising a number of Lactobacillus plantarum cells with a characteristic of interest.
The Lactobacillus plantarum composition may comprise different types or strains of Lactobacillus plantarum cells (e.g. the two different Lactobacillus plantarum CHCC14254 and CHCC14255 strains discussed herein). In essence the composition shall simply comprise the amount of Lactobacillus plantarum cells given in the first aspect herein, wherein the Lactobacillus plantarum cells comply with the criteria given in the first aspect.
As known to the skilled person, herein commercially relevant Lactobacillus plantarum cell compositions are generally made by fermentation. The obtained Lactobacillus plantarum cells are generally concentrated, dried, mixed with a carrier and packed into a suitable container.
The relevant e.g. 10 4 to 10 14 CFU/g Lactobacillus plantarum cells of the composition may be present in a commercially relevant form known to the skilled person.
Accordingly, in an embodiment 10 4 to 10 14 CFU/g Lactobacillus plantarum cells of the composition are present as dried (e.g. spray dried) cells or as frozen cells.
In a preferred embodiment the Lactobacillus plantarum composition comprises from 10 6 to 10 14 CFU/g Lactobacillus plantarum cells, more preferably from 10 8 to 10 14 CFU/g Lactobacillus plantarum cells.
The term “CFU/g” relates to the gram weight of the composition as such, including suitable relevant additives present in the composition. It does not include the weight of a suitable container used to package the Lactobacillus plantarum composition.
An embodiment relates to that the Lactobacillus plantarum composition is packaged into a suitable container.
As known to the skilled person a commercially relevant bacterial composition generally also comprises other relevant suitable additives.
Beside the herein relevant Lactobacillus plantarum cells the composition may also comprise other relevant microorganisms of interest such as e.g. other lactic acid bacteria of interest or yeast cells of interest (such as e.g. wine yeast cells of interest).
Assay to Select for an Increased Resistance to D-cycloserine
As discussed above the D-cycloserine resistance assay of point (i) of first aspect is based on known commercially available standard elements (such as e.g. standard media, etc).
Accordingly, based on the detailed assay description herein (see e.g. example 1 herein) the skilled person is routinely able to repeat this assay to objectively determine whether a specific cell of interest complies with the D-cycloserine resistance criteria as described in point (i).
As discussed above—one may say that the level of resistance as required in the assay of example 1 is a resistance to D-cycloserine that is significantly higher than normally present in natural/wildtype Lactobacillus plantarum strains.
The detailed conditions of example 1 herein is herein a preferred assay to determine if a Lactobacillus plantarum cell of interest complies with the criteria of point (i) of first aspect.
Increased Resistance to D-cycloserine—Point (i) of First Aspect
It may be preferred that the increased resistance to D-cycloserine is higher than the one given in point (i) of the first aspect herein.
Accordingly, it may be preferred that the Lactobacillus plantarum cells have an increased resistance to D-cycloserine—defined by that the cells are Lactobacillus plantarum cells, wherein the amount of D-cycloserine that reduces the OD 600 measured growth, after 24 hours growth at 18° C., with 50% in the known Grape Juice GJ-5 medium as compared to the growth in the GJ-5 medium without D-cycloserine (i.e. with 0 μg/ml D-cycloserine) is higher than 80 μg/ml D-cycloserine or is higher than 90 μg/ml D-cycloserine.
Assay to Select for an Improved Resistance Towards Ethanol
As discussed above the ethanol resistance assay of point (ii) of first aspect is based on known commercially available standard elements (such as e.g. standard media, etc).
Accordingly, based on the detailed assay description herein (see e.g. example 2 herein) the skilled person is routinely able to repeat this assay to objectively determine whether a specific cell of interest complies with the ethanol resistance criteria as described in point (ii).
The detailed conditions of example 2 herein is herein a preferred assay to determine if a Lactobacillus plantarum cell of interest complies with the criteria of point (ii) of first aspect.
Improved Resistance Towards Ethanol—Point (ii) of First Aspect
It may be preferred that the improved resistance towards ethanol is higher than the one given in point (ii) of the first aspect herein.
Accordingly, it may be preferred that the Lactobacillus plantarum cells have an improved resistance towards ethanol—defined by that the cells are Lactobacillus plantarum cells, wherein the cells can grow to an OD 600 of at least 0.8 after 3 days incubation at 25° C. in the GJ-5 medium with 11.5% ethanol or with 12% ethanol or with 13% ethanol.
A Method for Producing a Wine
As said above a second aspect of the invention relates to a method for producing a wine comprising administering the Lactobacillus plantarum composition of first aspect and herein described related embodiments to a grape juice or wine and performing further adequate steps to make the wine.
The wine may be any wine of interest such as red wine, white wine or sparkling wine such as Cava/champagne.
As know to the skilled person—for commercial relevant wine production there is generally administrated around Lactobacillus plantarum cells 10 6 CFU per ml grape juice or wine.
Accordingly, in a preferred embodiment of the method of the second aspect of the invention—there is administrated from 10 4 CFU to 10 8 CFU Lactobacillus plantarum cells per ml grape juice or wine, more preferably there is administrated from 10 5 CFU to 10 7 CFU Lactobacillus plantarum cells per ml grape juice or wine.
A Method for Cocoa Bean Fermentation
As known in the art— Lactobacillus plantarum cells have been used for cocoa bean fermentation.
In line of this—a herein relevant use of the Lactobacillus plantarum cells as described herein is use for cocoa bean fermentation—i.e. a method for cocoa bean fermentation, wherein a Lactobacillus plantarum composition as described herein is inoculated to the cocoa bean and then fermented.
A Method for Silage Production
As known in the art— Lactobacillus plantarum cells have been used for silage production.
In line of this—a herein relevant use of the Lactobacillus plantarum cells as described herein is use for silage production—i.e. a method for silage production, wherein a Lactobacillus plantarum composition as described herein is inoculated to the silage and then fermented.
A Method for Screening and Isolating a Novel Lactobacillus plantarum Cell
As said above, the third aspect relates to a method for screening and isolating a novel Lactobacillus plantarum cell.
In the method of the third aspect, a Lactobacillus plantarum cell capable of fulfilling the conditions of point (i) and (ii) of the first aspect is selected for.
As understood by the skilled person, the specific herein detailed described D-cycloserine resistance and ethanol resistance assays (see e.g. example 1 herein for D-cycloserine resistance assay and example 2 herein for ethanol resistance assay) parameters may be changed to make a alternative screening method that still obtains the main goals as described herein, i.e. a Lactobacillus plantarum cell that is capable of fulfilling the conditions of point (i) and (ii) of the first aspect.
Without being limited to theory—it could maybe be possible to use a functionally equivalent antibiotic to D-cycloserine as a selective agent to get the increased resistance to D-cycloserine of point (i) of the first aspect.
In the present context, the term “functionally equivalent antibiotic” should be understood as an antibiotic with the same mode of action or the same target as D-cycloserine, such as e.g. other inhibitors of D-alanyl-D-alanine ligases, such as e.g. vancomycin and other inhibitors of D-alanine racemase, such as e.g. O-carbamoyl-D-serine, alaphosphin and the haloalanines.
For instance, without being limited to theory—it could maybe be possible to use the functionally equivalent antibiotic vancomycin as the selective pressure agent and thereby get selected strains that are vancomycin resistant and then maybe also resistant to D-cycloserine as discussed herein (i.e. a Lactobacillus plantarum cell that is capable of fulfilling the conditions of point (i) of the first aspect).
As evident to the skilled person—the end result of step (b) is the isolation of a novel Lactobacillus plantarum that is capable of fulfilling the conditions of point (i) and (ii) of the first aspect.
Accordingly, a separate aspect of the invention relates to a Lactobacillus plantarum cell, which is capable of fulfilling the conditions of point (i) and (ii) of the first aspect and is obtainable by the screening method of the third aspect herein.
It is evident that this novel Lactobacillus plantarum cell of this separate aspect can be used to make a Lactobacillus plantarum composition of the first aspect.
Step (a) of the method for screening and isolating a novel Lactobacillus plantarum cell of the third aspect reads “selecting and isolating from a pool of individual Lactobacillus plantarum cells”.
As known—it is routine work for the skilled person to make/create such a pool of individual Lactobacillus plantarum cells.
It may e.g. be made from a suitable preferred starting cell, which may be subjected to suitable mutagenesis (e.g. using a chemical mutagen or UV mutagenesis) to make a pool of mutants of said starting cell—i.e. to create a pool of individual Lactobacillus plantarum cells.
As discussed in working Example 3 herein—the starting Lactobacillus plantarum cell CHCC14158 was subjected to mutagenesis (using D-cycloserine as selective agent) and from the created pool of individual Lactobacillus plantarum cells was subsequently selected the novel ethanol resistant cells CHCC14254 and CHCC14255 according to the selection method as described herein.
Alternatively, one could e.g. start from cells already made to have herein relevant resistance to D-cycloserine—such as e.g. Lactobacillus plantarum cells described in the article of Bron et al. (2002) as discussed above.
Relevant Lactobacillus plantarum cells of the Bron et al. (2002) could then e.g. be subjected to a suitable mutagenesis and then selected for improved resistance towards ethanol as discussed herein.
EXAMPLES
Example 1
Cycloserine Resistance Selection Assay
Medium: The medium is the known Grape Juice GJ-5 medium described in column 20, lines 10 to 20 of U.S. Pat. No. 7,112,346 (Chr. Hansen A/S).
As described in lines 10 to 20 of U.S. Pat. No. 7,112,346—the GJ-5 medium has the following composition:
Grape juice concentrate 70.0 g Yeast paste 30.0 g Tween 80 0.5 g MnSO 4 H 2 O 0.1 g Tap water 900.0 g
As known to the skilled person—this GJ-5 medium is a medium that is considered to be representative for a grape juice used for wine production.
Further, as understood by the skilled person in the present context—a grape juice concentrate is a standard well known ingredient of such a medium.
In the present context and as understood by the skilled person—the specific Grape juice concentrate may be supplied from different suppliers and independently of the specific supplier one will (within standard measurement uncertainty) get the same herein relevant result of cycloserine resistance for a herein relevant cell of interest.
A Lactobacillus plantarum strain of interest is inoculated into 10 ml GJ-5 medium containing one of the following amounts of D-cycloserine: 0 μg/ml, 10 μg/ml, 20 μg/ml, 30 μg/ml, 50 μg/ml, 70 μg/ml, 100 μg/ml, 150 μg/ml or 200 μg/ml of D-cycloserine. The strain is grown 24 hours at 18° C. in the GJ-5 medium with the different concentrations of D-cycloserine.
After the 24 hours growth is OD 600 measured for all samples.
A Lactobacillus plantarum cell that has an increased resistance to D-cycloserine as discussed herein—is herein defined as a Lactobacillus plantarum cell, wherein the amount of D-cycloserine that reduces the OD 600 measured growth, after 24 hours growth at 18° C., with 50% in GJ-5 medium as compared to the growth in GJ-5 medium without D-cycloserine (i.e. with 0 μg/ml D-cycloserine) is higher than 70 μg/ml D-cycloserine.
Cells that are capable of complying with this increased resistance to D-cycloserine criteria are herein defined as cells that are positively resistant to D-cycloserine in the D-cycloserine resistance assay of this example 1.
Conclusion:
Based on the Cycloserine resistance Selection assay of this Example 1—for a specific strain of interest (e.g. one from a relevant commercial product)—the skilled person can routinely test if this specific strain of interest has the herein relevant Cycloserine resistance.
Example 2
Ethanol Screening Resistance Assay
Medium: The medium is the standard GJ-5 medium as used in Example 1 above.
A Lactobacillus plantarum cell that has an improved resistance towards ethanol as discussed herein—is herein defined as a Lactobacillus plantarum cell that can grow to an OD 600 of at least 0.8 after 3 days incubation at 25° C. in the GJ-5 medium with 11% ethanol.
Cells that are capable of complying with this improved resistance towards ethanol criteria are herein defined as cells that are positively resistant to ethanol in the ethanol resistance assay of this example 2.
Conclusion:
Based on the Ethanol resistance assay of this Example 2—for a specific strain of interest (e.g. one from a relevant commercial product)—the skilled person can routinely test if this specific strain of interest has the herein relevant Ethanol resistance.
Example 3
Use of D-cycloserine to Isolate Mutants of Lactobacillus plantarum with Improved Resistance to High Concentrations of Ethanol
Strains
Lactobacillus plantarum CHCC14158
Lactobacillus plantarum CHCC14255 (D-cycloserine mutant of CHCC14158 isolated at 18° C. in GJ-5)
Lactobacillus plantarum CHCC14254 (D-cycloserine mutant of CHCC14158 isolated at 18° C. in GJ-5)
Mutant Isolation
Measured according to Example 1 above— Lactobacillus plantarum CHCC14158 is a cell, wherein the amount of D-cycloserine that reduces the OD 600 measured growth with 50% in GJ-5 medium as compared to the growth in GJ-5 medium without D-cycloserine (i.e. with 0 μg/ml D-cycloserine) is lower than 70 μg/ml D-cycloserine, since the amount of D-cycloserine that reduced the growth with 50% was around 60 to 65 μg/ml D-cycloserine—see e.g. FIG. 1 herein.
Accordingly, Lactobacillus plantarum CHCC14158 is not positively having increased resistance to D-cycloserine as defined in Example 1 above.
Lactobacillus plantarum strain CHCC14158 was subjected to D-cycloserine pressure as described below. The D-cycloserine worked here as a selective agent to create a pool of mutant cells with increased resistance to D-cycloserine.
In order to isolate mutants of the Lactobacillus plantarum strain CHCC14158, cells derived from the growth of a single colony were inoculated into GJ-5 medium of Example 1 containing various concentrations of D-cycloserine in the range of 25-100 μg/ml D-cycloserine and grown to saturation at 18° C. or at 25° C.
Surviving cells were diluted and plated on GJ-5 plates (without D-cycloserine) and colonies were screened in microtiter plates for the ability to grow in the presence of various concentrations of D-cycloserine in the range of 25-100 μg/ml D-cycloserine in GJ-5 medium.
25% of the resulting colonies were identified as fast growers in the presence of D-cycloserine—i.e. they were positively resistant to D-cycloserine in the D-cycloserine resistance assay of example 1.
These mutants were chosen for further study. The selected D-cycloserine resistant mutants were further purified and tested for their ability to grow in GJ-5 added various concentrations of ethanol in the range 5-14% ethanol or wine at 18° C. and 25° C. During this screening it was observed that approximately 10% of the mutants were more resistant to high concentrations of ethanol.
Two mutant derivatives of CHCC14158, designated CHCC14255 and CHCC14254, were significantly more resistant to high concentrations of ethanol than the mother strain when the growth was compared in GJ-5 at 25° C. in the presence of 11, 12 and 13 ethanol of parental strain CHCC14158 and two cycloserine resistant mutants CHCC14255 and CHCC14254.
The two cycloserine resistant mutants CHCC14255 and CHCC14254 could both grow to an OD 600 of at least 0.8 after 3 days incubation at 25° C. in the GJ-5 medium with 11% ethanol—for CHCC14255 the OD 600 was more than 1—i.e. both strains were positively resistant to ethanol in the ethanol resistance assay of this example 2.
The starting CHCC14158 strain could only grow to an OD 600 of around 0.65—i.e. the starting CHCC14158 strain was not positively resistant to ethanol in the ethanol resistance assay of this example 2.
The cycloserine resistance of both the CHCC14255 and CHCC14254 mutants was tested according to Example 1 above and both positively had the required increased resistance to D-cycloserine as required in Example 1.
For CHCC14255 the amount of D-cycloserine that reduces the OD 600 measured growth with 50% in GJ-5 medium as compared to the growth rate in GJ-5 medium without D-cycloserine (i.e. with 0 μg/ml D-cycloserine) was around 100 μg/ml D-cycloserine (see FIG. 1 herein).
For CHCC14254 the amount of D-cycloserine that reduces the OD 600 measured growth with 50% in GJ-5 medium as compared to the growth in GJ-5 medium without D-cycloserine (i.e. with 0 μg/ml D-cycloserine) was around 100 μg/ml D-cycloserine (see FIG. 1 herein).
Example 4
Reference/Control Experiment
UV mutagenesis was done on a Lactobacillus plantarum strain CHCC12396.
It is a strain with similar properties to Lactobacillus plantarum strain CHCC14158 that was used a starting cell in Example 3 above.
Screening for ethanol was done as in Example 3 above—however, after analysis of more than 100 different mutants/colonies it was not possible to select a mutant with improved resistance towards ethanol as defined in Example 2 above.
REFERENCES
1: U.S. Pat. No. 7,625,745 B2 (Danstar Ferment, CH)
2: Bron et al., 2002 Appl Environ Microbiol. 68:5663-5670
3: U.S. Pat. No. 7,112,346 (Chr. Hansen A/S) | Cycloserine resistant mutants of lactic acid bacteria characterized by having improved resistance towards ethanol. The cycloserine resistant mutants of lactic acid bacteria can e.g. be used for malolactic fermentations of wine (i.e. including sparkling wine such as Cava/champagne) having high alcohol levels. | 2 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] The present application is a continuation application claiming priority to U.S. application Ser. No. 13/697,007, which is a US national phase entry of International Application number PCT/US11/36703, filed on May 16, 2011, which in turn claims priority to U.S. provisional patent application No. 61/334,794, filed on May 14, 2010. The content of each of the latter-referenced applications is incorporated herein in its entirety by reference.
FIELD OF THE INVENTION
[0002] The invention relates to a plumbing trap system for passing waste liquids into a sewer pipe while preventing odors from escaping into the surrounding air, more specifically the invention provides a trap that uses a dual passage of waste liquids: a free (unobstructed) passage and a controlled passage of waste liquids.
BACKGROUND OF THE INVENTION
[0003] The demand for freshwater is on a constant rise, and consequently, so is the awareness to conserve fresh water. One of the ways to conserve freshwater is to use water drain systems that do not require flush with water. Using water free urinals is a good example of a water saving solution. The idea of water free drains has been contemplated by many inventors. The basic problems flush free urinals have to solve is passing urine to the sewer pipes without leaving an exposed we area where microbes can develop, while preventing urine odors from escaping into the air of the living spaces, and complying with plumbing regulations that demand that the flow of liquids through a trap may not be obstructed (or made potentially vulnerable to obstruction).
[0004] In order to address these problems, existing flush free urinals utilize a variation of a U-shaped trap that collects urine in a compartment while minimizing the contact between the collected urine and the surrounding air. Whereas, other types of urinals additionally use a sealant liquid, that is typically an oily substance that floats over the urine in a drain trap and prevents passing of odors from the urine into the air in the inhabitable spaces, see for instance Atwill (U.S. Pat. No. 6,589,440 B2) and Gorges (U.S. Pat. No. 6,053,197).
[0005] The liquid sealant approach is more efficient at blocking odors from escaping into the surrounding air. However, the sealant liquid partially mixes with urine at each use, and a portion of it passes to the sewer pipe with each use. Furthermore, if the urinal is infrequently used, the urine evaporates in between uses, allowing a portion of the sealant liquid to pass from the inlet side of the trap to the outlet side of the trap, and on the next use a more substantial portion of the sealant liquid is lost. Therefore, if the urinal is not frequently used, is requires more frequent replenishment of the sealant liquid, thus raising the burden and cost of maintenance.
[0006] Furthermore, in order to minimize the loss of liquid sealant in existing water free traps, the turbulence caused by incoming urine into the urinal has to be minimized. Thus, the flow rate through existing traps is kept at a minimum. The latter bring another drawback to existing water free urinals, which is the accumulation of solid waste in the trap, also leading to a necessity for frequent maintenance.
[0007] Due to the above drawbacks, despite the potential for significant water saving, current flush free urinals have not been widely adopted. The reason for the lack of widespread adoption may be attributed to a lack of performance for some types of flush free urinals, and/or the relatively high maintenance cost for other types of urinals. For example some flush free urinals do not reduce the smell of urine to a comfortable level. On the other hand, existing urinals that utilize a liquid sealant require a relatively frequent maintenance schedule. The sealant liquid is lost due to normal use and must be replenished after a certain number of uses. Additionally, the least the urinal is used the higher the loss of liquid sealant per use, and the more often the liquid sealant has to be replenished.
[0008] Gorges (U.S. Pat. No. 6,973,939) describes a cartridge type for hosting the sealant liquid, and working as a trap. The latter approach allows for an easy replacement of the cartridge. However, given the draw backs of the sealant liquid discussed above, the cost of frequent replacement of a cartridge is also prohibitive to the point of exceeding the cost of using water to flush the urinal. Because of the maintenance cost, liquid sealant based type urinals is mostly beneficial in places with very high frequency of use.
[0009] Therefore, there is a need for an economical system for disposing of waste liquids without requiring flushing, while keeping a odor sealant in the trap when the urinal is not used, or infrequently used, and can be easily maintained.
SUMMARY OF THE INVENTION
[0010] The invention provides a drain trap system that does not require flushing for draining a waste liquid. The drain trap system is for use in urinals, sinks, floor drains and any other type of drain that intended to block a back flow of odors from the waste liquid. The invention uses a sealant liquid in the trap. The sealant liquid is selected for being non-miscible (and non-dissolvable) in the waste liquid and for having a density lower than that of the waste liquid. Thus, when the sealant liquid is mixed together with the waste liquid the former separates and floats on top of the latter, resulting in the sealant liquid forming a barrier against odors to pass from the waste liquid into the air.
[0011] The drain trap, in accordance with the invention, uses two passageways: the first passageway is similar to any existing trap. The latter passageway is based on a U-shaped trap that allows free flow of liquid from an inlet side to an outlet side, thus allowing substantial flow, which prevents overflow. The U-shaped trap also keeps a residual amount of liquid that remains stagnant in the drain to function as a plug (or barrier) for preventing a back flow of odors from the sewers back into the living spaces.
[0012] The second passageway connects the bottom of the trap with the sewer using a tubing (or a pipe). The tubing (or pipe) is connected to a release opening at the bottom of the trap. The release opening is controlled by a valve. The valve itself is controlled by a floating mechanism. When there is an inflow of waste liquid, the level of liquids in the trap rises, causing the floating mechanism to act on the valve and open it. The liquid closest to the bottom of the trap (i.e., the liquid having the higher density), then, flows through the release opening via the tubing toward the sewer line, causing in return the level of liquid in the trap to drop, and the floating mechanism to go down to a level where the valve returns to a closed position. A key feature in the design of any embodiment of the invention is to allow a residual quantity of waste liquid and an amount of sealant liquid to keep an odor barrier in place when the drain is not being used. Therefore, by allowing a waste liquid to pass through the liquid barrier, then flow through the release opening toward the sewer, it is possible to minimize the loss of the sealant liquid. The remaining sealant liquid in the trap serves as a barrier to prevent air contact between the residual quantity of waste liquid that also remains in the trap and the ambient air, both preventing odor back flow and reducing evaporation of the remaining waste water. The latter is important in the case of infrequently used urinals, for example, which minimizes the loss of sealant liquid.
[0013] Thus, the invention provides a drain trap system that is in compliance with sanitation codes and regulations, since it allows a free flow passageway through the drain. The trap minimizes the loss of sealant during heavy use, and requires less maintenance when infrequently used. Furthermore, when a trap embodying the invention is used in a urinal, because of the novel way the waste liquid is drained toward the sewer line without being sensitive to liquid turbulence in the trap, the urinal bowl may be designed with steep sides so as to speed up the travel of urine along the walls of the bowl, thus minimizing the time urine is in contact with the surrounding air.
DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1A is a sectional side view schematically representing a trap and drain assembly in accordance with embodiments of the invention.
[0015] FIG. 1B is in comparison with FIG. 1A and schematically illustrates the operation of a trap assembly in accordance with an embodiment of the invention.
[0016] FIG. 2 schematically represent sample features that may be considered when building a device in accordance with an embodiment of the invention.
[0017] FIG. 3 schematically represents a side view cross section of a urinal built following the teachings of the invention as described above.
DETAILED DESCRIPTION OF THE INVENTION
[0018] The invention provides a plumbing trap assembly for draining a waste liquid while blocking odors from escaping into the breathable air (e.g., around persons in living spaces) without necessitating the use of water to flush the drain after each flow of the waste liquid.
[0019] In the following description, numerous specific details are set forth to provide a more thorough description of the invention. It will be apparent, however, to one skilled in the pertinent art, that the invention may be practiced without these specific details. In other instances, well known features have not been described in detail so as not to obscure the invention. The claims following this description are what define the metes and bounds of the invention.
Terminology
[0020] Throughout the disclosure the terms “trap”, “drain trap” and “drain” refers to a plumbing odor trap as describe in the prior art, such as S-trap, P-Trap, Q-trap, bottle-trap or any other trap used to prevent air contact between the sewer and living spaces. It will be apparent to one with ordinary skills in the pertinent art that the invention may practiced with any available trap designs and adapted for any specific application embodying the invention as disclosed herein. The disclosure uses U-shaped trap terminology to refer to any trap (including the above-mentioned types of traps) that uses gravity in order to keep a residual amount of liquid in a trap, and allow free flow from the inlet side to the outlet side (i.e. sewer) of the trap.
[0021] The air (or breathable air) is used to refer to the space where odors or any other chemical is undesired.
Description of the Basic Concept
[0022] An embodiment of the invention is a plumbing odor trap assembly that may be attached to the bottom of a liquid receiver, such the bowl of a urinal, for passing the waste liquid to a sewer line. The trap is initially filled with a sealant liquid. The sealant liquid is selected to be non-miscible in the waste liquid, and its specific density is lower than that of the waste liquid. For example, for implementations in a urinal apparatus, a sealant liquid may be a hydrophobic liquid having a lower specific density than that of urine allowing the sealant liquid to settle and float on the top of the urine in a mixture of sealant and urine. The trap assembly, in accordance with the invention, provides two (2) passageways for liquids: the first passageway works similarly to a conventional trap, allowing passage of any liquid without obstruction, thus preventing overflow, while retaining a residual amount of liquid to act as an odor trap and prevent odors from diffusing from the sewers into breathable air. The second passageway, in accordance with the invention, comprises a release opening near the bottom of the trap connected with a tubing to the sewer line. A valve (or a similar occluding element) is used to close the opening at the bottom of the trap. The valve is combined with a floating mechanism. The floating mechanism is placed within the trap and is able to float within the liquids inside the trap. The valve and the floating mechanism are designed such that an upward movement (or an up position) under the influence of buoyancy causes the valve to open (or stay open), and vice versa, a downward movement (or down position), for lack of sufficient buoyancy, puts the valve in a closed position. Thus, When the amount of liquids in the trap is below a predetermined level, the valve remains in a closed position. When the drain receives waste water through the inlet of the drain, the waste water flows toward the bottom of the trap, in accordance with the specific densities of the separate liquids described above, and the total level of liquids rises, thus providing the buoyancy for the floating mechanism that automatically causes the valve to open. Since the waste water is located at the bottom of the trap, near the bottom opening, it flows through the opening and via the tubing toward the sewer line. When the level of liquids in the trap falls to (or below) the predetermined level, then the valve closes. The predetermined level of liquid may be designed to keep a portion of the waste water in the trap and all (or at least most) of the sealant liquid in the trap. The remaining sealant liquid in the trap acts as a barrier between the waste liquid and the air.
[0023] FIG. 1A is a sectional side view schematically representing a trap and drain assembly in accordance with embodiments of the invention. The trap and drain system 101 , in accordance with the invention, may be attached to the main body for receiving waste liquids, such as the bowl of a urinal 100 . The trap and drain assembly comprises a main compartment 102 (i.e. an inlet) for receiving waste liquid. The main compartment 102 is connected to the drain pipes 110 through a generally U-shaped (or S-shaped) pipe 104 , and allows unobstructed flow of any liquid through the trap. The latter is generally a compliance requirement with the plumbing sanitation and building code. The inlet to the trap and drain may be covered with a cover 134 , which allows urine to flow toward the main compartment. The cover 134 may possess some shape design features, the utility of which would be to reduce the velocity of the urine as it enters main compartment 102 . Reducing the velocity of the waste liquid as it mixes with the sealant liquid allows for a better separation of the two liquids, thus promoting fast settlement of the waste liquid at the bottom of the trap. The cover 134 may also be tightly fitted so as to allow passing waste liquid while block solid objects the size of which is above a given size, such as cigarette butts, paper waste or any other undesired solid object whose size exceeds a given limit.
[0024] At (or close to) the bottom of the trap and drain system, a release opening 124 allows waste liquid to flow through a pipe 126 toward the main drain 110 leading to the sewer line.
[0025] The opening is occluded by a valve system. The valve system is combined with a floating mechanism that is under the influence of buoyancy from the liquids. In the absence of sufficient buoyancy, valve 122 closes opening 124 . When enough liquid is present in the trap, buoyancy pushes the floating mechanism upward sufficiently to open the valve and allow the waste liquid to flow through opening 124 toward the sewer.
[0026] For example, valve 122 may be connected to a floating element 120 . A floating element connector 123 connects the valve with the floating element. The length of connector 123 may be designed to be adjustable and its length may be used to determine the amount of liquids that can be retained in the trap.
[0027] In other embodiments of the invention, the valve itself my be designed to respond to buoyancy with a weight and density that allows buoyancy to push the valve upward sufficiently to open opening 124 .
[0028] The valve (and/or floating mechanism) may be hosted in a separate compartment 106 , such as shown in FIG. 1A , having one or more holes 130 connecting the compartment 106 with the main compartment 102 . The holes allows the pressure to be balanced between compartments 102 and 106 liquids to freely move between compartments.
[0029] FIG. 1B is in comparison with FIG. 1A and schematically illustrates the operation of a trap assembly in accordance with an embodiment of the invention. Waste liquid 164 flows from a receiving container 100 , into the inlet of a trap embodying the invention. The waste liquid having a higher density than that of the sealant liquid, and being non-miscible with the latter flows toward the bottom (e.g., 165 ), without any significant mixing. As the waste liquid accumulates in the trap, the level of both liquids rises as indicated by level line 162 , while the thickness of the sealant layer, as indicated by 160 and 161 , remains constant. The top level of all liquids however rises, providing buoyancy to the floating mechanism (e.g., floating element 120 ), thus causing the valve to open and release waste liquid from the bottom layer. When sufficient waste liquid (e.g. 168 ) has been released through opening 124 , valve 122 returns to its down position, closing opening 124 and stopping the flow of the waste liquid, and eventually keeping a residual amount of waste liquid in the trap.
[0030] Embodiments of the invention prevent loss of sealant liquid from the trap, and allow the thickness of the sealant layer 160 to remain constant while the layer of urine increases and decreases depending on the flow level of waste liquid.
[0031] FIG. 2 schematically represent sample features that may be considered when building a device in accordance with an embodiment of the invention. One or more of the following features may be present either individually or in any combination in a device embodying the invention. FIG. 2 is only a representation of these features. Each feature may be considered separately of in combination when constructing an embodiment of the invention.
[0032] Filtering System.
[0033] In order to allow for maximum efficiency of the trap assembly, a mesh filter may be utilized to filter urine before passing through the valve and opening. A mesh filter 210 may be lowered in the main compartment and may possess a release opening 212 toward the main passageway toward the sewer line allowing for unobstructed passage of liquid towards the main drain. The mesh 212 may be designed for frequent removal and cleaning.
[0034] Floating Body and Valve Control.
[0035] FIG. 2 schematically illustrates how a buoyancy-driven valve 220 may be implemented. A valve may have a ball shape and (e.g., made of rubber) and having a predetermined mass and density such that it is floats when the level of liquid reaches a predetermined level. Otherwise when buoyancy is below a predetermined level, the valve remain in place within a receptacle (e.g., element 225 ) closing the opening toward the second passageway.
[0036] Valve Guiding System.
[0037] Valve 220 may be guided and kept in place using a rigid guides (e.g., retainers) 225 built around the opening 124 .
[0038] Pressure Balance.
[0039] In order to prevent a pressure buildup in any of the compartment in the trap and release system, special tubing (e.g. tubing 230 ) may be used to connect any of the compartments to the main drain, provided that it does not allow a back flow of air from the sewer line into the air. The pressure balance line allows for balancing pressure and preventing odorous gases from passing into the air of living spaces.
A Flush-Free Urinal
[0040] FIG. 3 schematically represents a side view cross section of a urinal built following the teachings of the invention as described above. The urinal of FIG. 3 comprises a receptacle 300 for receiving urine. The receptacle in its entirety, or at least the upper surface of the receptacle, may be built using a hydrophobic material, in order to minimize the adhesion of urine droplets to the surface of the receptacle 300 .
[0041] Because a trap embodying the invention may be designed to prevent loss of sealant liquid due to liquid turbulence, the walls of receptacle 300 may steep, so as to minimize the time the urine 310 is exposed in the air before it flows into the trap 305 . As described above, urine flow into the trap and through a layer of sealant liquid. The trap bottom 320 may be shaped such that it collects solid debris, and configured to minimize turbulence as the urine passes through the sealant liquid. For example, the bottom of compartment 320 may be shaped with a depression that dampens the motion of the liquids and allows the urine to quickly separate from the sealant liquid before passing into a second 330 compartment where it may flow through an opening.
[0042] The second compartment 330 , which may be narrow and deep, may serve to connect to a release opening using a secondary pipe leading to the sewer pipe. The depth and narrowness of compartment 330 allow only the urine, and not the sealant liquid, to reach release opening 332 . Valve 336 is designed to close the release opening when the urinal is not in use, and generally when the level of liquids in the trap are below a predetermined level, otherwise, when urine is received in the urinal, as the level of liquids rises and provide enough buoyancy to the floating mechanism, valve 336 is lifted opening the release opening 332 , thus causing the accumulated urine to flow out of the trap and toward the sewers. When the level of liquids in the trap returns to a predetermined level, valve 336 automatically closes release opening 332 .
[0043] Therefore, from the receiving of urine in a flush-free urinal embodying the invention, to the flowing of urine below the sealant layer, to the disposing of the urine into the sewer pipe, there is minimal contact between the urine and the surrounding air. More importantly, the urine is disposed of without requiring flushing with water as it is the case with existing urinal.
[0044] Thus, a trap and drain assembly that allows for disposing of waste liquids while preventing a back flow of odorous gases from the sewers without requiring flushing. The concept of trap and drain of the invention, provides a plurality of benefits over the prior art. In the prior art, the loss of the sealant liquid elevated as a result of liquid turbulence, which typically occurs at the receiving and mixing of urine with the sealant liquid. The latter forces the design to a flush-free trap to reduce the speed of the flow of urine into the trap, thus lengthening the time urine is exposed to ambient air. Because an embodiment of the invention prevents (or at least minimizes) the loss of sealant due to turbulence, a urinal in accordance with the invention, allows for designing a urinal receptacle (with steep walls) such that time urine is in contact with the ambient air is minimal. As a result of the latter, there is less undesired smell escaping into the air.
[0045] The flush free urinals of the prior art utilize shape features inside the trap in order to retain as much sealant liquid as possible in order to lower the cost of maintenance. These shape features coincidentally also trap solid wastes which renders prior art traps hard (or even impossible) to clean and put back in service. As a result prior art water free traps are designed to be replaced periodically, leading to a high cost of maintenance.
[0046] A trap and drain embodying the invention, by using two separate passageways allows for the filtering (potentially through a mesh filter, or simply through decantation) of the waste liquid. Furthermore, when solid waste is trapped in the trap, or as a preventative maintenance measure, the trap of the invention allows a user to flush the trap with sufficient amounts of water, then refill the trap with a sufficient amount of sealant liquid.
[0047] Another benefit, overtime if solid deposits (e.g., calcite minerals) accumulate in the trap it is possible to fill the trap with a solution to dissolve the solids, then flush the trap with sufficient amounts of water, and refill the trap with the sealant liquid.
[0048] Prior art water free urinals suffer from the fact that if a urinal is infrequently used, the residual urine in the urinal evaporates, leaving the sealant to remain in equal proportions on both the inlet and outlet sides. At the next use of the urinal, the portion of the sealant present on the outlet side of the trap is pushed out of the trap and lost. In short, the least they are used, the more they necessitate replenishment of the sealant liquid. The latter leads to an increased cost of maintenance. Furthermore, because of the latter drawback it is not practical to use the prior urinals in places where, for example, hot weather and/or in remote areas, where the residual urine may evaporate within hours, or maintenance cannot be provided as necessitated by the frequency of use.
[0049] A trap built following the teachings of the invention allows a layer of sealant liquid to remain above a residual portion of the urine, thus preventing (or at least significantly slowing down) evaporation of the residual urine. Since the sealant liquid remains in the trap (even if the urine evaporates), the next use of the urinal does not lead to any significant loss of sealant liquid.
[0050] The drain trap and release system is in compliance with sanitation codes and regulations. The trap and release system may be installed in the urinal. It is capable of preventing odors from escaping into the air and in living spaces, and does not dry out when the urinal is not frequently used. A device embodying the invention presents numerous advantages compared to prior art. When a urinal according to the invention is not used over long periods of time, the residual urine is kept below a layer of hydrophobic liquid. The latter prevents the urine from evaporating which would otherwise cause all sealant to settle at the bottom and be lost at the next use. It is possible to design the trap such a turbulence, that typically cause urine to mix so when the assailant, can be minimized. Furthermore, because of the physical separation it is also possible to implement a filter that removes solid chunks from the urine as it is gradually drained. The latter characteristics allow one with ordinary skills in the pertinent art to design a trap with removable parts (e.g., bottom of the compartments such 320 and 330 ) of for easy cleaning and maintenance. For example a filter e.g. 112 may be inserted into the trap in order to filter urine that is gradually drained and capture other solids they may settle to the bottom of the drain. For maintenance purposes, the filter may be removed cleaned and or replaced. Furthermore, the trap and drain system in accordance with the invention may be cleaned using industrial detergents to dissolve deposits, then cleaned with water followed by replenishment of the sealants liquid. The latter is a significant advantage over existing solutions which require replacement of a cartridge.
[0051] Thus, a trap assembly for use in a drain to dispose of waste liquid while blocking a back flow of odors from the waste liquid and/or sewer line. | The invention provides a flush free drain trap system. The trap of the invention may be used in any trap system intended to block a back flow of odors from the waste line. A sealant liquid floats on top of the waste liquid in the trap to block odors. The trap uses one passageway to pass liquids to the sewer line, similarly to a conventional drain system, for preventing overflow and allowing cleaning. A second passageway allows the trap to dispose of small amounts of the waste liquid through an opening and a valve operated by the buoyancy caused by the accumulation of waste liquid in the trap. In normal use, waste liquid is passed to the sewer line without loss of sealant liquid. Furthermore, the performance of the trap is not affected by the evaporation of the waste liquid when the trap is unused. | 4 |
BACKGROUND OF THE INVENTION
This invention is concerned with a clamp for use in sealing the gap between a pair of confronting pipe flanges integral with the ends of two pipes which have been bolted together to form part of a pipe line. Such flanges are usually bolted together using an intervening gasket to prevent leakage. When the flanges are bolted together, the gasket, in the form of an annular seal, is clamped between the flanges, normally radially inwardly of the bolts. If the gasket develops a fault, because it has been subjected to the prolonged action of corrosive fluid, for example, then a leak may occur through it and release fluid between the flanges. If the fluid supply cannot conveniently be interrupted, then steps may have to be taken to stop the leak whilst the pipe still contains fluid and until a permanent repair can be effected.
One conventional procedure for closing such leaks is to hammer a malleable wire into the annular gap between the confronting outer edges of the flanges; these edges are then peened over to hold the wire in place. Holes are then drilled or tapped through at least one of the flanges into the space between the wire and the existing, but leaking gasket and a sealant material is then injected through these holes to fill the space and at the same time stop the leak. This procedure of caulking with wire followed by drilling holes and injecting a sealant material is a very specialised technique which requires significant skill and training if it is to be carried out safety and effectively. In particular, great care has to be taken when drilling the holes if the pipe is carrying a potentially explosive fluid. Typically the invention is concerned with leaks in the flanged joints of high pressure lines for industrial processes involving, for example, water, steam, acid, various gases, hydrocarbons, compressed air or oil. The kind of hazard which may be involved is self-evident.
DESCRIPTION OF THE INVENTION
This invention provides a clamp comprising a ring to be positioned about a pair of confronting pipe flanges, means for tightening the ring against the flanges, the ring having a circumferential, inwardly facing groove in an inner surface thereof, together with an insert for said groove formed from a pressure deformable material and an outwardly-directed face which is received in the groove in the ring and an inwardly-directed face with a substantially symmetrical taper adapted, when the ring is tightened in use, to sealingly engage the opposed margins of an annular gap defined between said confronting flanges.
This clamp replaces the wire caulking which is utilised in the method discussed earlier and the application of the clamp is a relatively simple procedure which can be carried out by an unskilled mechanic. A closed annular space is created between the insert and an existing gasket in place between the flanges, sealing material can thereafter be injected into this space. The tapered face of the insert locates the insert fairly precisely, so that the clamp is substantially symmetrically self-aligned with respect to the gap between the flanges; the circumferential groove formed in the ring holds the insert securely in place.
The insert is preferably formed from lead but may comprise some other pressure deformable malleable metal, natural or synthetic rubber, or a malleable plastics material. In preferred form the inwardly directed groove formed in the ring is of U-shaped cross-section; it is preferably straightsided (i.e. square or rectangular in section). It is possible however to form the groove in the ring as an arc of a circle in cross-section. In this latter case, the abutting portion of the insert can also be of circular, or part circular cross-section. In fact, the outwardly directed face of the insert may be of curved form, whatever shape of groove in the ring is employed. However it is generally preferred that the inwardly-directed face of the insert should be of pointed (tapered) configuration so as to guide the insert positively towards and into engagement with the margins defining the gap between the flanges. This combination of a recess in the ring with a malleable, shaped insert is important, because it ensures that in use, there is very little or no risk at all of the clamp being displaced sideways by an accidental blow. Positive location is achieved without regard to flange thickness axially of the pipe, so that the clamp is of universal application, for a given flange diameter.
The ring itself may be in the form of two semicircular parts with integral lugs provided with aligned holes through which securing bolts can be applied to tighten the ring against the flanges. Alternatively, the ring could be in the form of two semicircular parts hinged together at one end and carrying integral lugs at their other end, through which pass aligned holes to receive a bolt for tightening the ring against the flanges. A particularly advantageous feature of the clamp is that one or more holes can be drilled in the ring beforehand so as to pass through the ring radially inwardly along or close to the centre line of the recess or groove. Then when the ring and insert are secured about the flanges the only drilling required is to continue the existing drill holes through the deformable material forming the insert. For most insert materials there will be no great resistance to this operation, thereby obviating or at least greatly reducing the risk of undesirable heating and/or the possibility of sparks due to metal-to-metal contact. This is extremely important where the leaking fluid is inflammable or explosive. The pre-drilled holes constitute sealant injection ports and replace the holes which would otherwise have to be drilled in the flanges themselves.
The invention also extends to a method of sealing a leak from between a pair of confronting pipe flanges, wherein a clamp of the kind previously recited is applied about the flanges so that the inwardly directed face of the insert engages the margins of an annular gap defined between the flanges and the ring is then tightened, whereby the insert is deformed into sealing engagement with said margins.
Preferably the method of the invention includes the further step of filling the annular space created between the insert and an existing gasket installed radially inwardly of the edges of the flanges with a sealant material, after the ring has been tightened into position about the flanges. When a clamp which has drilled holes already formed in the ring is employed then the method will also include drilling a hole through the material of the insert as a continuation of each of the drill holes provided in the ring after the ring has been tightened into position, followed by injecting a sealant material into the space between the flanges through the or each hole so formed. This will normally be followed by plugging the or each hole to prevent extrusion of the sealant material.
DETAILED DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the invention will now be described by way of example with reference to the accompanying drawings, in which:
FIG. 1 is an end view of a ring forming part of a clamp according to the invention;
FIG. 2 is a cross-section on line 2--2 of FIG. 1 and also through an insert to be used with the ring of FIG. 1;
FIG. 3 is a section on line 3--3 of FIG. 1 through the complete clamp when positioned about a pair of confronting flanges at the ends of two pipe sections;
FIG. 4 illustrates, in cross-sections, a modified form of distortion of the sealing insert;
FIG. 5 is a cross-section through a sealing insert after deformation; and
FIGS. 6 to 8 are cross-sections through portions of modified forms of clamps of this invention.
The clamp illustrated in FIGS. 1 and 2 comprises a pair of semicircular half-rings 1 with integral lugs 2, each half ring being formed with an annular, rectangular cross-section groove 3 on its inner surface the groove receives an insert 4 (FIG. 2) formed from lead. As is seen in FIG. 2, the cross-sectional profile of the insert provides a radially outermost face 5 which fits into the groove 3 of the ring and an inwardly-directed face 6, which is of tapered section so as to locate the insert accurately within a gap defined between a pair of confronting flanges. Part of a pipe line comprising two pipe sections terminating in confronting circular flanges 8 is illustrated in FIG. 3 and the in-use location of the clamp of FIGS. 1 and 2 is shown in this Figure. The confronting pipe flanges 8 on the ends of the sections 7 are held together by bolts 9 passing through and between the flanges 8 so as to clamp them against a gasket 10. Assuming that the gasket 10 breaks down so that a pressurised fluid carried by the pipe 7 can escape past it and into the gap between the flanges 8, it may well be necessary to find some way of stopping the leak until a permanent repair can be made. Sometimes it is not feasible to immediately remove the gasket and replace it, because in order to do that, the pipe line must be drained and the flange joint dismantled. The desired, basic leak-stopping function is provided by the clamp provided by the parts 1 and 4. The two halves of the ring are positioned about the flanges 8 so that the tapered face 6 of the insert 4 engages the margins defining the gap between the flanges 8, and thereby centralises the whole clamp about the centre line of this gap. The two halves of the ring 1 are tightened together by bolts (not shown) passing through holes 11 (in FIGS. 1 and 2) in the lugs 2 of the ring halves. This results in distortion of the sealing insert into the gap between the flanges 8 and at the same time also sideways against the flanges 8 and the adjacent parts of the ring 1. This defines a closed annular space 12 between the insert 4 and the existing leaking gasket 10. Pre-drilled holes 13 are provided in the ring; these are shown in FIGS. 1 and 3. These holes are extended by drilling through the lead insert 4 to communicate with the space 12, as shown in FIG. 3 and a sealing material can then be injected into the space 12 through the holes 13 to complete an auxiliary seal. Injection can be accomplished with the aid of the grease gun type tool commonly used in this art. The holes 13 may be screw-threaded to permit plugging after injection, or they may be fitted with one way valves, e.g. grease nipples.
Subsequent heating of the assembly as well as the operating conditions of the pipe line are obviously restricted by the properties of the lead as well as by the choice of sealant material, since in the pure state the melting point of lead is 327° C. It is believed that working temperatures to 250° C. may be acceptable. From simple tests on samples of a lead insert, in the deformed and undeformed states, it is estimated that pressures in excess of 5000 lbf/in 2 would be necessary to cause collapse of of the lead insert in the flange gap. This magnitude of pressure is greatly in excess of that normally used for sealant injection, since there is a tendency for small amounts of sealant to escape near/along flange bolt holes and at the interface between the lugs 2, thereby causing some pressure relief.
Whilst the intention is that the tapered portion 6 of the insert will provide accurate self-alignment of the clamp centrally of the centre line of the gap between the flanges 8, a certain amount of misalignment can be tolerated. This could occur if the two flanges 8 are somewhat eccentrically aligned, so that there is a slight overlap as illustrated in FIG. 4. However, even though the centre line of the clamp is not aligned with the centre line between the two clamps 8, in the configuration as shown in FIG. 4, this is not absolutely critical since the extension of the drill hole 13 through the lead insert 4 will still communicate with the space 12. If the drill should contact one flange 8 it will tend to be deflected down the side of the flange until the drill has passed completely through the insert 4. Another possibility is that, as the two halves of the ring are tightened about the flanges a degree of misalignment of the insert around at least part of the circumference of the clamp may occur as illustrated in FIG. 5. For a flange cap which is say 0.6 mm wide the sealing clamp may be offset by a maximum of 0.3 mm.
Alternative configurations for the ring and the insert are illustrated in FIGS. 6 and 8. In each of these arrangements there is still a groove in the ring which locates the insert and ensures that it does not slip sideways with respect to the sealing ring. Thus a curved groove, as shown in FIGS. 6 and 8, is adequate for this purpose although the rectangular groove as shown in FIGS. 2 and 7 is preferred. Furthermore satisfactory centralisation of the insert in the gap between the flanges 8 will be achieved if the inwardly directed face of the insert is of a curved shape, as illustrated in FIGS. 7 and 8, although again, for most purposes a pointed (tapered) face as illustrated in FIGS. 2 and 6 is preferred as being more convenient to use on a real leak, where visibility may be minimal due to the leaking fluid.
Whilst the insert 4 is described as being formed from lead it may be constructed from some other malleable or deformable material. Copper or brass is a possibility but this might prove to be insufficiently malleable to create the deformation required and it is more difficult to drill (and of course to mould into the initial shape) than lead. Malleable plastics materials are also feasible but must be carefully chosen so that they are inert to any chemicals which may be present in or leaking from the pipe line. The temperature of the contents of the latter needs to be considered in this context. With regard to the sealant material used in any circumstances, many such compounds are commercially-available based on room temperature vulcanising (RTV) or thermally vulcanisable rubbers, thermosettable plastics and the like, with or without reinforcing fillers, such as fibres. Compounds are available for most of the commonly encountered leaking fluids. The choice of compound is a matter for the technician dealing with the leak, of course. | A clamp is provided to seal the gap between a pair of flanges (8) of connected sections of pipe (7) when a gasket (10 ) between the pipe sections fails. The sealing clamp comprises a pair of half-rings (1) incorporation rectangular grooves (3) which receive a lead sealing insert (4) formed with a tapered face (6) opposite that which is received in the groove (3). The half-rings (1) have terminal lugs bored to receive bolts by means of which the clamp can be tightened about the flanges (8), with the result that the insert (4) is distorted to form an effective annular seal for the gap between the flanges (8). The tapered face (6) ensures that the clamp is self-centering and that the clamp is not likely to be displaced sideways if subjected to an accidental blow. Pre-drilled holes (13) in the half-rings (1) can be continued through the insert (4) to enable a sealing compound to be injected. | 5 |
BACKGROUND
[0001] Semiconductor devices, such as integrated circuit (IC) packages, typically include one or more semiconductor devices arranged on a lead frame or carrier. The semiconductor device is attached to the lead frame, typically by an adhesive die attach material or by soldering, and bond wires are attached to bond pads on the semiconductor devices and to lead fingers on the carrier to provide electrical interconnections between the various semiconductor devices and/or between a semiconductor device and the carrier. The device is then encapsulated in a plastic housing, for instance, to provide protection and form a housing from which the leads extend.
[0002] With such semiconductor packages, especially power semiconductor components, it is desirable to provide high current load-carrying capacity. To this end, some solutions for providing the desired connection density or current capacity require an insulation layer to avoid electrical contact between the conductive connections and the semiconductor device/carrier.
[0003] For these and other reasons, there is a need for the present invention.
SUMMARY
[0004] In accordance with aspects of the present disclosure, an integrated circuit device includes a semiconductor device having an integrated circuit. A gas-phase deposited insulation layer is disposed on the semiconductor device, and a conducting line is disposed over the gas-phase deposited insulation layer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] Embodiments of the invention are better understood with reference to the following drawings. The elements of the drawings are not necessarily to scale relative to each other. Like reference numerals designate corresponding similar parts.
[0006] FIG. 1 is a block diagram conceptually illustrating a top view of an integrated circuit device in accordance with embodiments of the present invention.
[0007] FIGS. 2-6 are side views conceptually illustrating various aspects of an integrated circuit device in accordance with embodiments of the present invention.
[0008] FIG. 7 is a block diagram conceptually illustrating a top view of a multi-chip module in accordance with embodiments of the present invention.
DETAILED DESCRIPTION
[0009] In the following Detailed Description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. In this regard, directional terminology, such as “top,” “bottom,” “front,” “back,” “leading,” “trailing,” etc., is used with reference to the orientation of the Figure(s) being described. Because components of embodiments of the present invention can be positioned in a number of different orientations, the directional terminology is used for purposes of illustration and is in no way limiting. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present invention. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims.
[0010] FIG. 1 is a schematic top view conceptually illustrating an integrated circuit device in accordance with exemplary embodiments of the present invention. The exemplary integrated circuit device 100 includes a semiconductor device, or chip, 110 attached to a lead frame or carrier 112 . An insulation layer 114 is deposited over the chip 110 , and a conductive layer including conductive lines 116 is deposited over the insulation layer 114 to provide electrical interconnections between the chip 110 and the carrier 112 . For example, in certain embodiments, the conductive layer 116 includes generally flat copper strips interconnecting the chip 110 with source and gate terminals 120 , 122 .
[0011] As illustrated in FIG. 1 , the planar conductive connections 116 to the source terminals 120 are relatively wide (100 μm or more in exemplary embodiments) to provide the desired current and heat conductivity. The connection to the gate terminal 122 in the illustrated embodiment is thinner, allowing smaller lateral structures.
[0012] In accordance with aspects of the invention, the insulation layer 114 is gas-phase deposited. Among other things, using a gas-phase deposition rather than foil technology provides improved adhesion of the insulation layer 114 on the chip 110 and carrier 112 . Further, applying the insulation layer from the gas phase can provide better surface wetting, a higher surface reactivity and good conformance to the surface topography under the insulation layer 114 . Still further, the gas-phase deposited insulation layer 114 has a high thermal stability and imparts a relatively small thermal-mechanical stress on the device since the process can take place at ambient temperature in certain implementations.
[0013] FIGS. 2-6 conceptually illustrate side views of portions of the integrated circuit device 100 in a block diagram form. In FIG. 2 , the semiconductor device 110 is attached to the lead frame 112 , which includes a source potion 120 and drain portion 122 separated by a gap 124 . In exemplary embodiments, the semiconductor device 110 is attached in a conventional manner, such as with an adhesive die attach material or tape, soldering, etc. In FIG. 3 , the gap 124 between the source 120 and drain 122 is filled with an insulating material 126 to prevent shorts between the source 120 and drain 122 . The insulating material 126 permanently or temporarily fills the gap 124 to facilitate the process of applying an insulation layer.
[0014] FIG. 4 illustrates the insulation layer 114 deposited over the chip 110 and lead frame 112 . Typically, materials such as epoxy, polyamide or silicone would be used for the insulation layer 114 , and would be applied in the liquid phase, for example, by a spin coating process. In the illustrated embodiment the insulation layer 114 is deposited in the gas phase, for example, by a chemical vapor deposition (CVD). In exemplary embodiments, the insulation layer 114 thickness varies from about 1-100 μm, 20-50 μm thick in certain embodiments.
[0015] In one embodiment, the insulation layer 114 is a plasmapolymer, and in particular, the plasmapolymer is a Parylene, such as Parylene C, Parylene N, or Parylene D. Parylenes are particularly well suited as insulation materials. They have a high electrical insulation strength. In addition, Parylene takes up only very little moisture and is comparatively elastic, so that it can buffer thermomechanical stresses between the semiconductor device 110 and adjacent layers. In addition, Parylenes often have low coefficients of thermal expansion of less than 50 ppm/K, a high thermal stability and a high chemical resistance.
[0016] Particularly, Parylene C provides a useful combination of chemical and physical properties plus a very low permeability to moisture, chemicals and other corrosive gases. Parylene C has a melting point of 290° C. Parylene N provides high dielectric strength and a dielectric constant that does not vary with changes in frequency. Parylene N has a melting point of 420° C. Parylene D maintains its physical strength and electrical properties at higher temperatures. Parylene D has a melting point of 380° C.
[0017] In another embodiment, the insulation layer 114 includes an amorphous inorganic or ceramic carbon type layer. The amorphous inorganic or ceramic carbon type layer has an extremely high dielectrical breakthrough strength and a coefficient of thermal expansion (CTE) of about 2-3 ppm/K, which is very close to the CTE of silicon of about 2.5 ppm/K. In addition, the amorphous inorganic or ceramic carbon type layer has a temperature stability up to 450-500° C.
[0018] FIG. 5 illustrates the device 100 with the insulation layer 114 formed, such as by photolithographic processes, etching, laser ablation, etc. In FIG. 6 , the device 100 is illustrated including the conductive layer 116 deposited on the insulation layer 114 , providing interconnections between the chip 110 and the periphery of lead frame 112 . The device can then be encapsulated, by any suitable molding process, for example, resulting in the encapsulation or housing 130 .
[0019] The process disclosed above is also suitable also for the contacting of a plurality of semiconductor devices in a multi-chip module. In such a multi-chip module, the interconnections between the semiconductor components can be produced in the same way and at the same time as the connections from the semiconductor devices to the periphery of the carrier. FIG. 7 illustrates an exemplary multi-chip module 200 in accordance with embodiments of the invention. The multi-chip module 200 includes semiconductor devices situated on a carrier 112 . A gas-phase deposited insulation layer 114 is deposited over the semiconductor devices and the carrier 112 , and the multi-chip module 200 is surrounded by an encapsulation 130 .
[0020] The semiconductor devices include first and second power transistors 210 , 212 mounted on the carrier 112 . A logic device 214 is mounted on the power transistor 210 . Alternatively, the logic device 214 can be arranged along side the power transistors 210 , 212 if space allows. The power transistors 210 , 212 are arranged in a half bridge configuration, with the drain connection 220 of the high side device 212 connected to the source 222 of the low side device 210 by conductive lines 116 deposited on the insulation layer 114 . The logic device 214 is connected for controlling the power transistors 210 , 212 via their gate contacts 224 . Conductive connections 116 are further situated between various terminals of the semiconductor devices and contacts 230 situated at the periphery of the package 200 , with the insulation layer 114 situated between the chips/carrier and the deposited conductive connections 116 . The configuration shown can be extended the addition of further semiconductor components as well as passive elements, for example.
[0021] Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations may be substituted for the specific embodiments shown and described without departing from the scope of the present invention. This application is intended to cover any adaptations or variations of the specific embodiments discussed herein. Therefore, it is intended that this invention be limited only by the claims and the equivalents thereof. | An integrated circuit device includes a semiconductor device having an integrated circuit. A gas-phase deposited insulation layer is disposed on the semiconductor device, and a conducting line is disposed over the gas-phase deposited insulation layer. | 7 |
This is a continuation of application Ser. No. 389,114, filed Aug. 17, 1973, now abandoned.
FIELD OF THE INVENTION
This invention relates to new rodenticidal compositions effective against small rodents such as, for example rats and mice.
BACKGROUND OF THE INVENTION
It is known that several derivatives of 1,3-indanedione, particularly those disclosed in the Applicants' French Pat. No. 1,269,638, have the property of lowering the amount of prothrombin in the blood and as a result can be used as rodenticides, because they bring about in rodents a high mortality rate due to internal haemorrhage. Such anticoagulant substances are usually mixed with a carrier which can be eaten by the rodents, for example a cereal, to form a bait. A disadvantage of such a bait is that on prolonged storage it becomes heterogeneous with the result that the rodenticidal substance accumulates towards the bottom of the bait, so that the uniform rodenticidal activity of the bait is lost.
SUMMARY OF THE INVENTION
It has now been found that, in order to destroy certain varieties of rodents, such as Pitymys Pinetorum (pine mouse), Pitymys subterraneus de Selys Longchamps (underground vole), Pitymys duodecimcostatus de Selys Longchamps (Mediterranean pine vole), Arvicola Sapidus (water vole), Arvicola Terrestus (land vole), Microtus arvalis pallas (meadow mouse), Apodemus Sylvaticus (field mouse), Fiber Zibethicus (musk rat), which live in fields, meadows, orchards, seed-beds, nurseries and the like, it is advantageous for the anticoagulant substance to be finely and uniformly sprayed over large areas wherein are growing vegetables which serve as animal feed, for the rodents to be destroyed. The spraying operation can most conveniently be carried out with liquid compositions which contain the anticoagulant substance in dissolved form or in suspension, it being possible for such compositions to be diluted with from 10 to 500 times their volume of water at the time of use. The diluted emulsions can be sprayed onto the ground by means of the spraying devices normally used in agriculture, so as to provide a regular distribution of the anticoagulant substance.
These liquid compositions have the advantage of not becoming separated into their constituents throughout the time which a spraying operation lasts, of not causing damage to the apparatus used for the spraying and of not clogging the orifices of these latter.
DETAILED DESCRIPTION OF THE INVENTION
Thus, in accordance with the present invention, there is provided a rodenticidal composition comprising a solution or emulsion of 2-(α-p-chlorophenyl-α-phenylacetyl)-1,3-indanedione (the common name for which is "chlorophacinone") in a liquid monocyclic aromatic hydrocarbon solvent in the presence of an emulsifier.
Benzene and benzene derivatives which are substituted by one or more straight- or branched-chain saturated alkyl radicals are suitable for use as the aromatic hydrocarbon solvent in the rodenticidal composition.
It is advantageous to use, as the benzene derivative, benzene substituted by at least one methyl, ethyl, propyl, isopropyl, butyl, isobutyl, amyl, isoamyl, sec. amyl, tert. amyl or isohexyl radical.
The benzene may be substituted by several identical, or by different, alkyl radicals.
Xylene (i.e. dimethylbenzene) is a solvent which has been found to be particularly suitable. Xylene can be used in the form of a mixture of its three isomers, or in the o-xylene (1,2-dimethylbenzene), m-xylene (1,3-dimethylbenzene) or p-xylene (1,4-dimethylbenzene) form.
Toluene (i.e. methylbenzene), as well as cumene (i.e. isopropylbenzene), and cymene (i.e. isopropyl-methylbenzene) used in the form of a mixture of isomers or in the form of o-cymene (2-isopropyl-1-methylbenzene), m-cymene (3-isopropyl-1-methylbenzene), or p-cymene (4-isopropyl-1-methylbenzene) are solvents which have also been found to be most useful.
Examples of other useful solvents are amylbenzene, sec. amylbenzene, tert. amylbenzene, isoamylbenzene, butylbenzene, sec. butylbenzene, tert. butylbenzene, isobutylbenzene, ethylbenzene, diethylbenzene in the 1,2 1,3 or 1,4-positions, triethylbenzene in the 1,2,4 or 1,3,5-positions, propylbenzene, pentamethylbenzene, pentaethylbenzene, isohexylbenzene, o-propyl-toluene (1-methyl-2-propylbenzene), m-propyl-toluene (1-methyl-3-propylbenzene) and p-propyl-toluene (1-methyl-4-propylbenzene).
The chlorophacinone may be present in the composition in an amount of from 5 to 10%, preferably 6 to 8%, by weight, whilst the aromatic hydrocarbon solvent may be present in an amount of from 75 to 85%, preferably 75 to 80%, by weight.
The rodenticidal composition contains an emulsifier, which may be present in an amount of from 2 to 20% by weight, preferably about 10%. The emulsifier may be a soluble metallic sulphonate or a polyoxyethylene ether, or mixtures thereof.
If desired, the rodenticidal composition can contain dipropylene glycol in an amount of up to 5% by weight.
If further desired, the rodenticidal composition may contain a fixative adjuvant in an amount of up to 1% by weight. This adjuvant can be poly-(methylene-p-nonylphenoxy)-ω-poly-(oxypropylene) or 1,3-dihydroxypropane.
When required for use, the rodenticidal composition of the invention will normally be diluted with from 10 to 500 times its volume of water to form an emulsion ready for spraying.
EXAMPLES
The following Examples illustrate the invention.
EXAMPLE 1
______________________________________Formula No. 1 2 3 4 5 6______________________________________Chlorophacinone 6 8 6 8 6 8Dipropylene glycol 0 0 5 5 5 5Emulsifier 10 10 10 10 10 10Fixative adjuvant 0 0 1 1 0 0Xylene 84 82 78 76 79 77______________________________________
EXAMPLE 2
______________________________________Formula No. 7 8 9 10 11 12______________________________________Chlorophacinone 5 7 6 8 5 9Dipropylene glycol 5 0 5 5 5 0Emulsifier 10 10 10 10 10 10Fixative adjuvant 0 1 0 0 1 0Benzene 80 82 79 77 79 81______________________________________
EXAMPLE 3
______________________________________Formula No. 13 14 15 16 17 18______________________________________Chlorophacinone 10 8 6 8 6 8Dipropylene glycol 0 5 0 5 5 5Emulsifier 10 10 10 10 10 10Fixative adjuvant 0 0 1 1 0 0Toluene 80 77 83 76 79 77______________________________________
EXAMPLE 4
______________________________________Formula No. 19 20 21 22 23 24______________________________________Chlorophacinone 6 8 6 8 6 8Dipropylene glycol 0 0 5 5 5 5Emulsifier 10 10 10 10 10 10Fixative adjuvant 0 0 1 1 0 0Cumene 84 0 0 76 0 77Cymene 0 82 78 0 79 0______________________________________
EXAMPLE 5
______________________________________Formula No. 25 26 27 28 29 30______________________________________Chlorophacinone 6 8 6 8 6 8Dipropylene glycol 0 0 5 5 5 5Emulsifier 10 10 10 10 10 10Fixative adjuvant 0 0 1 1 0 0Amylbenzene 84 -- -- -- -- --Butylbenzene -- 82 -- -- -- --Ethylbenzene -- -- -- 76 -- --1,2-Diethyl-benzene -- -- 78 -- -- --Triethyl-benzene -- -- -- -- -- 77Propyl-benzene -- -- -- -- 79 --______________________________________
EXAMPLE 6
The rodenticidal activity of the compositions of the invention was verified in the following manner: 1 kg. of wheat grains was spread over a flat surface of 1 square meter in a single layer, so that all the grains were in contact with the surface. A quantity of the rodenticidal composition was diluted with water to obtain 100 ml. of an aqueous emulsion containing 0.050 g. of chlorophacinone. This aqueous emulsion was sprayed uniformly over the surface of the grains.
The sprayed grains were given for consumption by rats placed under the test conditions of the protocol defined at the International Conference in London in October 1958 concerned with destruction of rodents considered as vermin. The rodenticidal activity is the ratio between dead rats after 8 days and the number of rats used in the test.
______________________________________Formula No. Mortality Formula No. Mortality______________________________________1 9/10 16 9/102 9/10 17 10/103 10/10 18 10/104 10/10 19 9/105 8/10 20 8/106 9/10 21 8/107 10/10 22 9/108 9/10 23 10/109 9/10 24 9/1010 8/10 25 10/1011 8/10 26 9/1012 9/10 27 8/1013 10/10 28 10/1014 9/10 29 9/1015 8/10 30 10/10______________________________________ | Rodenticidal compositions in the form of solutions or emulsions are formed from an anticoagulant substance in a liquid aromatic hydrocarbon solvent in the presence of an emulsifier.
These compositions, when diluted with water, can be used for the destruction of rodents by spraying the areas in which grow vegetables serving as foodstuffs for the rodents to be destroyed. | 8 |
FIELD OF INVENTION
This invention relates to a high performance multi-media communications cable utilizing paired or unpaired electrical conductors or optical fibers. More particularly, it relates to cables having a central core defining singular or plural individual pair channels. The communications cable has an interior core support-separator that defines a clearance through which conductors or optical fibers may be disposed.
BACKGROUND OF THE INVENTION
Many communication systems utilize high performance cables normally having four pairs or more that typically consist of two twisted pairs transmitting data and two receiving data as well as the possibility of four or more pairs multiplexing in both directions. A twisted pair is a pair of conductors twisted about each other. A transmitting twisted pair and a receiving twisted pair often form a subgroup in a cable having four twisted pairs. High-speed data communications media in current usage includes pairs of wire twisted together to form a balanced transmission line. Optical fiber cables may include such twisted pairs or replace them altogether with optical transmission media (fiber optics).
When twisted pairs are closely placed, such as in a communications cable, electrical energy may be transferred from one pair of a cable to another. Energy transferred between conductor pairs is undesirable and referred to as crosstalk. The Telecommunications Industry Association and Electronics Industry Association have defined standards for crosstalk, including TIA/EIA-568A. The International Electrotechnical Commission has also defined standards for data communication cable crosstalk, including ISO/IEC 11801. One high-performance standard for 100 MHz cable is ISO/IEC 11801, Category 5. Additionally, more stringent standards are being implemented for higher frequency cables including Category 6 and Category 7, which includes frequencies of 200 and 600 MHz, respectively.
In conventional cable, each twisted pair of conductors for a cable has a specified distance between twists along the longitudinal direction. That distance is referred to as the pair lay. When adjacent twisted pairs have the same pair lay and/or twist direction, they tend to lie within a cable more closely spaced than when they have different pair lays and/or twist direction. Such close spacing increases the amount of undesirable crosstalk that occurs. Therefore, in many conventional cables, each twisted pair within the cable has a unique pair lay in order to increase the spacing between pairs and thereby to reduce the crosstalk between twisted pairs of a cable. Twist direction may also be varied. Along with varying pair lays and twist directions, individual solid metal or woven-metal air shields can be used to electromagnetically isolate pairs from each other or isolate the pairs from the cable jacket.
Shielded cable, although exhibiting better crosstalk isolation, is more difficult, time consuming and costly to manufacture, install, and terminate. Individually shielded pairs must generally be terminated using special tools, devices and techniques adapted for the job, also increasing cost and difficulty.
One popular cable type meeting the above specifications is Unshielded Twisted Pair (UTP) cable. Because it does not include shielded pairs, UTP is preferred by installers and others associated with wiring building premises, as it is easily installed and terminated. However, UTP fails to achieve superior crosstalk isolation such as required by the evolving higher frequency standards for, data and other state of the art transmission cable systems, even when varying pair lays are used.
Some cables have used supports in connection with twisted pairs. These cables, however, suggest using a standard “X”, or “+” shaped support, hereinafter both referred to as the “X” support. Protrusions may extend from the standard “X” support. The protrusions of these prior inventions have exhibited substantially parallel sides.
The document, U.S. Pat. No. 3,819,443, hereby incorporated by reference, describes a shielding member comprising laminated strips of metal and plastics material that are cut, bent, and assembled together to define radial branches on said member. It also describes a cable including a set of conductors arranged in pairs, said shielding member and an insulative outer sheath around the set of conductors. In this cable the shielding member with the radial branches compartmentalizes the interior of the cable. The various pairs of the cable are therefore separated from each other, but each is only partially shielded, which is not so effective as shielding around each pair and is not always satisfactory.
The solution to the problem of twisted pairs lying too closely together within a cable is embodied in three U.S. Pat. Nos. 6,150,612 to Prestolite, 5,952,615 to Filotex, and 5,969,295 to CommScope incorporated by reference herein, as well as an earlier similar design of a cable manufactured by Belden Wire & Cable Company as product number 1711A. The prongs or splines in the Belden cable provide superior crush resistance to the protrusions of the standard “X” support. The superior crush resistance better preserves the geometry of the pairs relatives to each other and of the pairs relative to the other parts of the cables such as the shield. In addition, the prongs or splines in this invention preferably have a pointed or slightly rounded apex top which easily accommodates an overall shield. These cables include four or more twisted pair media radially disposed about a “+”-shaped core. Each twisted pair nests between two fins of the “+”-shaped core, being separated from adjacent twisted pairs by the core. This helps reduce and stabilize crosstalk between the twisted pair media. U.S. Pat. No. 5,789,711 to Belden describes a “star” separator that accomplishes much of what has been described above and is also herein incorporated by reference.
However, these core types can add substantial cost to the cable, as well as material which forms a potential fire hazard, as explained below, while achieving a crosstalk reduction of typically 3 dB or more. This crosstalk value is based on a cable comprised of a fluorinated ethylene-propylene (FEP) conductors with PVC jackets as well as cables constructed of FEP jackets with FEP insulated conductors. Cables where no separation between pairs exist will exhibit smaller crosstalk values. When pairs are allowed to shift based on “free space” within the confines of the cable jacket, the fact that the pairs may “float” within a free space can reduce overall attenuation values due to the ability to use a larger conductor to maintain 100 ohm impedance. The trade-off with allowing the pairs to float is that the pair of conductors tend to separate slightly and randomly. This undesirable separation contributes to increased structural return loss (SRL) and more variation in impedance. One method to overcome this undesirable trait is to twist the conductor pairs with a very tight lay. This method has been proven impractical because such tight lays are expensive and greatly limits the cable manufacturer's throughput (yield). An improvement included by the present invention to structural return loss and improved attenuation is to provide grooves within channels for conductor pairs such that the pairs are fixedly adhered to the walls of these grooves or at least forced within a confined space to prevent floating simply by geometric configuration.
In building designs, many precautions are taken to resist the spread of flame and the generation of and spread of smoke throughout a building in case of an outbreak of fire. Clearly, the cable is designed to protect against loss of life and also minimize the costs of a fire due to the destruction of electrical and other equipment. Therefore, wires and cables for building installations are required to comply with the various flammability requirements of the National Electrical Code (NEC) in the U.S. as well as International Electrotechnical Commission (EIC) and/or the Canadian Electrical Code (CEC).
Cables intended for installation in the air handling spaces (i.e. plenums, ducts, etc.) of buildings are specifically required by NEC/CEC/IEC to pass the flame test specified by Underwriters Laboratories Inc. (UL), UL-910, or its Canadian Standards Association (CSA) equivalent, the FT6. The UL-910 and the FT6 represent the top of the fire rating hierarchy established by the NEC and CEC respectively. Also important are the UL 1666 Riser test and the IEC 60332-3C and D flammability criteria. Cables possessing these ratings, generically known as “plenum” or “plenum rated” or “riser” or “riser rated”, may be substituted for cables having a lower rating (i.e. CMR, CM, CMX, FT4, FTI or their equivalents), while lower rated cables may not be used where plenum or riser rated cables are required.
Cables conforming to NEC/CEC/IEC requirements are characterized as possessing superior resistance to ignitability, greater resistant to contribute to flame spread and generate lower levels of smoke during fires than cables having lower fire ratings. Often these properties can be anticipated by the use of measuring a Limiting Oxygen Index (LOI) for specific materials used to construct the cable. Conventional designs of data grade telecommunication cable for installations in plenum chambers have a low smoke generating jacket material, e.g. of a specially filled PVC formulation or a fluoropolymer material, surrounding a core of twisted conductor pairs, each conductor individually insulated with a fluorinated insulation layer. Cable produced as described above satisfies recognized plenum test requirements such as the “peak smoke” and “average smoke” requirements of the Underwriters Laboratories, Inc., UL910 Steiner tunnel test and/or Canadian Standards Association CSA-FT6 (Plenum Flame Test) while also achieving desired electrical performance in accordance with EIA/TIA-568A for high frequency signal transmission.
While the above described conventional cable, including the Belden 1711A cable design, due in part to their use of fluorinated polymers, meets all of the above design criteria, the use of fluorinated polymers is extremely expensive and may account for up to 60% of the cost of a cable designed for plenum usage. The solid core of these communications cables contribute a large volume of fuel to a potential cable fire. Forming the core of a fire resistant material, such as with FEP, is very costly due to the volume of material used in the core, but it should help reduce flame spread over the 20 minute test period.
Solid flame retardant/smoke suppressed polyolefins may also be used in connection with fluorinated polymers. Commercially available solid flame retardant/smoke suppressed polyolefin compounds all possess dielectric properties inferior to that of FEP and similar fluorinated polymers. In addition, they also exhibit inferior resistance to burning and generally produce more smoke than FEP under burning conditions.
A high performance communications data cable utilizing twisted pair technology must meet exacting specification with regard to data speed, electrical,as well as flammability and smoke characteristics. The electrical characteristics include specifically the ability to control impedance, near-end cross-talk (NEXT), ACR (attenuation cross-talk ratio) and shield transfer impedance. A method used for twisted pair data cables that has been tried to meet the electrical characteristics, such as controlled NEXT, is by utilizing individually shielded twisted pairs (ISTP). These shields insulate each pair from NEXT. Data cables have also used very complex lay techniques to cancel E and B (electric and magnetic fields ) to control NEXT. In addition, previously manufactured data cables have been designed to meet ACR requirements by utilizing very low dielectric constant insulation materials. Use of the above techniques to control electrical characteristics have inherent problems that have lead to various cable methods and designs to overcome these problems. Current designs must also meet the UL 910 flame and smoke criteria using both fluorinated and non-fluorinated jackets as well as fluorinated and non-fluorinated insulation materials for the conductors of these cable constructions. In Europe, the trend continues to be use of halogen free insulation for all components, which also must meet stringent flammability regulations.
Individual shielding is costly and complex to process. Individual shielding is highly susceptible to geometric instability during processing and use. In addition, the ground plane of individual shields, 360° in ISTP's—individually shielded twisted pairs is also an expensive process. Lay techniques and the associated multi-shaped anvils of the present invention to achieve such lay geometries are also complex, costly and susceptible to instability during processing and use. Another problem with many data cables is their susceptibility to deformation during manufacture and use. Deformation of the cable geometry, such as the shield, also potentially severely reduces the electrical and optical consistency.
Optical fiber cables exhibits a separate set of needs that include weight reduction (of the overall cable), optical functionality without change in optical properties and mechanical integrity to prevent damage to glass fibers. For multi-media cable, i.e. cable that contains both metal conductors and optical fibers, the set of criteria is often incompatible. The use of the present invention, however, renders these often divergent set of criteria compatible. Specifically, optical fibers must have sufficient volume in which the buffering and jacketing plenum materials (FEP and the like) covering the inner glass fibers can expand and contract over a broad temperature range without restriction, for example −40 C to 80 C experienced during shipping. It has been shown by Grune, et. al., among others, that cyclical compression and expansion directly contacting the buffered glass fiber causes excess attenuation light loss (as measured in dB) in the glass fiber. The design of the present invention allows for designation and placement of optical fibers in clearance channels provided by the support-separator, having multi-anvil shaped profiles. It would also be possible to place both glass fiber and metal conductors in the same designated clearance channel if such a design is required. In either case the forced spacing and separation from the cable jacket (or absence of a cable jacket) would eliminate the undesirable set of cyclical forces that cause excess attenuation light loss. In addition, fragile optical fibers are susceptible to mechanical damage without crush resistant members (in addition to conventional jacketing). The present invention also addresses this problem.
The need to improve the cable design, reduce costs, and improve both flammability and electrical properties continues to exist.
SUMMARY OF THE INVENTION
This invention provides a lower cost communications cable exhibiting improved electrical, flammability, and optionally, optical properties. The cable has an interior support extending along the longitudinal length of the communications cable. The interior support has a central region extending along the longitudinal length of the interior support. In the preferred configuration, the cable includes a geometrically symmetrical core support-separator with a plurality of either solid or foamed anvil-shaped sections that extend radially outward from the central region along the longitudinal or axial length of the cable's central region. The core support-separator is optionally foamed and has an optional hollow center. Each section is adjacent to each other with a minimum of two adjacent anvil-shaped sections. The anvil-shaped sections of the core support-separator may be helixed as the core extends along the length of the communications cable. Each of the adjacent anvil-shaped sections defines a clearance which extends along the longitudinal length of the multi-anvil shaped core support-separator. The clearance provides a channel for each of the conductors/optical fibers or conductor pairs used within the cable. The clearance channels formed by the multi-anvil shaped core support-separator extend along the same length of the central portion. The channels are either semi-circular or fully circular shaped cross-sections with completely closed surfaces in the radial direction toward the center portion of the core and optionally opened or closed surfaces at the outer radial portion of the same core. Adjacent channels are separated from each other to provide a chamber for at least a pair of conductors or an optical fiber or optical fibers.
The anvil-shaped core support-separator of this invention provides a superior crush resistance to the protrusions of the standard “X” or other similar supports. The superior crush resistance is obtained by the arch-like design of each clearance channel providing additional support to the outer section of the cable. The anvil-shaped core better preserves the geometry of the pairs relative to each other and of the pairs relative to the other parts of the cables, such as the possible use of a shield or optical fibers. In addition, the anvil-shape provides an exterior surface that essentially establishes the desired roundness for cable manufacturers. The exterior roundness ensures ease of die development and eventual extrusion. The rounded surface of the core also allows for easy accommodation of an overall external shield.
According to one embodiment, the cable includes a plurality of transmission media with metal and/or optical conductors that are individually disposed; and an optional outer jacket maintaining the plurality of data transmission media in proper position with respect to the core. The core is comprised of a support-separator having a multi-anvil shaped profile that defines a clearance to maintain a spacing between transmission media or transmission media pairs in the finished cable. The core may be formed of a conductive or insulative material to further reduce crosstalk, impedance and attenuation.
Accordingly, the present invention provides for a communications cable, with a multi-anvil shaped support-separator, that meets the exacting specifications of high performance data cables and/or fiber optics or the possibility of including both transmission media in one cable, has a superior resistance to deformation during manufacturing and use, allows for control of near-end cross-talk, controls electrical instability due to shielding, is capable of 200 and 600 MHz (Categories 6 and 7) transmission with a positive attenuation to cross-talk ratio (ACR ratio) of typically 3 to 10 dB.
Moreover, the present invention provides a separator so that the jacket material (which normally has inferior electrical properties as compared with the conductor material) is actually pushed away from the electrical conductor, thus acting to again improve electrical performance (ACR, etc.) over the life of the use of the cable. The anvil-shaped separator, by simple geometric considerations is also superior to the “X” type separator in that it increases the physical distance between the conductor pairs within the same cable configuration, as shown in FIGS. 2 and 3.
Additionally, it has been known that the conductor pair may actually have physical or chemical bonds that allow for the pair to remain intimately bound along the length of the cavity in which they lie. The present invention describes a means by which the conductor pairs are adhered to or forced along the cavity walls by the use of grooves. This again increases the distance, thereby increasing the volume of air or other dielectrically superior medium between conductors in separate cavities. As discussed above, spacing between pairs, spacing away from jackets, and balanced spacing all have an effect on final electrical cable performance.
It is an object of the invention to provide a data/multi-media cable that has a specially designed interior support that accommodates conductors with a variety of AWG's, impedances, improved crush resistance, controlled NEXT, controlled electrical instability due to shielding, increased breaking strength, and allows the conductors, such as twisted pairs, to be spaced in a manner to achieve positive ACR ratios.
It is still another object of the invention to provide a cable that does not require individual shielding and that allows for the precise spacing of conductors such as twisted pairs and/or fiber optics with relative ease. In the present invention, the cable would include individual glass fibers as well as conventional metal conductors as the transmission medium that would be either together or separated in clearance channel chambers provided by the anvil-shaped sections of the core support-separator.
Another embodiment of the invention includes having a multi-anvil shaped core support-separator with a central region that is either solid or partially solid. This includes the use of a foamed core and/or the use of a hollow center of the core, which in both cases significantly reduces the material required along the length of the finished cable. The effect of foaming and/or producing a support-separator with a hollow center portion should result in improved flammability of the overall cable by reducing the amount of material available as fuel for the UL 910 test, improved electrical properties for the individual non-optical conductors, and reduction of weight of the overall cable.
Another embodiment includes fully opened surface sections defining the core clearance channels which extend along the longitudinal length of the multi-anvil shaped core support-separator. This clearance provides half-circular channel walls for each of the conductors/optical fibers or conductor pairs used within the cable. A second version of this embodiment includes a semi-closed or semi-opened surface section defining the same core clearance channel walls. These channel walls would be semi-circular to the point that at least 200 degrees of the potential 360 degree wall enclosure exists. Typically, these channels walls would include and opening of 0.005 inches to 0.011 inches wide. A third version of this embodiment includes either a fully closed channel or an almost fully closed channel of the anvil-shaped core support-separator such that this version could include the use of a “flap-top” initially providing an opening for insertion of conductors or fibers and thereafter providing a covering for these same conductors or fibers in the same channel. The flap-top closure can be accomplished by a number of manufacturing methods including heat sealing during extrusion of the finished cable product. Other methods include a press-fit design, taping of the full assembly, or even a thin skin extrusion that would cover a portion of the multi-anvil shaped separator. All such designs could be substituted either in-lieu of a separate cable jacket or with a cable jacket, depending on the final property requirements.
Yet another embodiment of the invention allows for interior corrugated clearance channels provided by the anvil-shaped sections of the core support-separator. This corrugated internal section has internal axial grooves that allow for separation of conductor pairs from each other or even separation of single conductors from each other as well as separation of optical conductors from conventional metal conductors.
Alternatively, the edges of said grooves may allow for separation thus providing a method for uniformly locating or spacing the conductor pairs with respect to the channel walls instead of allowing for random floating of the conductor pairs.
Each groove can accommodate at least one twisted pair. In some instances, it may be beneficial to keep the two conductors in intimate contact with each other by providing grooves that ensure that the pairs are forced to contact a portion of the wall of the clearance channels. The interior support provides needed structural stability during manufacture and use. The grooves also improve NEXT control by allowing for the easy spacing of the twisted pairs. The easy spacing lessens the need for complex and hard to control lay procedures and individual shielding. Other significant advantageous results such as: improved impedance determination because of the ability to precisely place twisted pairs: the ability to meet a positive ACR value from twisted pair to twisted pair with a cable that is no larger than an ISTP cable; and an interior support which allows for a variety of twisted pair and optical fiber dimensions.
Yet another related embodiment includes the use of an exterior corrugated or convoluted design such that the outer surface of the support-separator has external radial grooves along the longitudinal length of the cable. This exterior surface can itself function as a jacket if the fully closed anvil-shaped version of the invention as described above is utilized. Additionally, the jacket may have a corrugated, smooth or ribbed surface depending on the nature of the installation requirements. In raceways or plenum areas that are new and no previous wire or cable has been installed, the use of corrugated surfaces can enhance flex and bending mechanical strength. For other installations, a smooth surface reduces the possibility of high friction when pulling cable into areas where it may contact surfaces other than the raceway or plenum. Mechanical integrity using an outer jacket such as depicted in FIGS. 2A, 2 B, or 2 C may be essential for installation purposes.
Alternatively, depending on manufacturing capabilities, the use of a tape or polymeric binding sheet may be necessary in lieu of extruded thermoplastic jacketing. Taping or other means may provide special properties of the cable construction such as reduced halogen content or cost and such a construction is found in FIG. 2 C.
Yet another related embodiment includes the use of a strength member together with, but outside of the multi-anvil shaped core support-separator running parallel in the longitudinal direction along the length of the communications cable. In a related embodiment, the strength member could be the core support-separator itself, or in an additional related embodiment, the strength member could be inserted in the hollow center-portion of the core.
According to another embodiment of the invention, the multi-anvil shaped core support-separator optionally includes a slotted section allowing for insertion of an earthing wire to ensure proper and sufficient electrical grounding preventing electrical drift.
Finally, it is possible to leave the multi-anvil shaped separator cavities empty in that the separator itself or within a jacket would be pulled into place and left for future “blown fiber” or other conductors along the length using compressed air or similar techniques such as use of a pulling tape or the like
It is understood that each of the embodiments above could include a flame-retarded, smoke suppressant version and that each could include the use of recycled or reground thermoplastics in an amount up to 100%.
A method of producing the communications cable, introducing an anvil-shaped core as described above, into the cable assembly, is described as first passing a plurality of transmission media and a core through a first die which aligns the plurality of transmission media with surface features of the core and prevents or intentionally allows twisting motion of the core. Next, the method bunches the aligned plurality of transmission media and core using a second die which forces each of the plurality of the transmission media into contact with the surface features of the core which maintain a spatial relationship between each of plurality of transmission media. Finally, the bunched plurality of transmission media and core are optionally twisted to close the cable, and the closed cable optionally jacketed.
Other desired embodiments, results, and novel features of the present invention will become more apparent from the following drawings and detailed description and the accompanying claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a top-right view of one embodiment of the cable and separator that includes solid or foamed polymeric smooth internal and external surfaces.
FIG. 1B is a top-right view of one embodiment of the cable and separator that includes solid or foamed polymeric grooved internal and external surfaces.
FIG. 1C is a top-right view of one embodiment of the cable and separator that includes solid or foamed polymeric corrugated internal and external surfaces.
FIG. 2A is a top-right view of one embodiment of the cable and separator that includes an anvil-shaped separator and a smooth/ribbed jacket.
FIG. 2B is a top-right view of another embodiment of the cable and separator that includes a ribbed, corrugated jacket.
FIG. 2C is a top-right view of another embodiment of the cable and separator that includes a taped or polymer binder sheet jacketing configuration.
FIG. 3A is a cross-section of the interior support or anvil-shaped separator taken along the horizontal plane of the interior support anvil-shaped separator.
FIG. 3B is a cross-section of the single flap, flap-top embodiment of the interior support or anvil-shaped separator taken along the horizontal plane of the interior support anvil-shaped separator when the flap is open.
FIG. 3C is a cross-section of the single flap, flap-top embodiment of the interior support or anvil-shaped separator taken along the horizontal plane of the interior support anvil-shaped separator when the flap is closed.
FIG. 3D is a cross -section version of the closed single-flap, flap-top embodiment of the anvil-shaped separator with flap-tops that are rounded at the tapered end.
FIG. 4A is a cross-section of the double flap, flap-top embodiment of the interior support or anvil-shaped separator taken along the horizontal plane of the interior support or anvil-shaped separator when the flaps are open.
FIG. 4B is a cross-section of the double flap, flap-top embodiment of the interior support or anvil-shaped separator taken along the horizontal plane of the interior support or anvil-shaped separator when the flaps are closed.
FIG. 4C is an enlarged detailed version of the closed double-flap, flap-top embodiment of the anvil-shaped separator.
FIG. 5 is a cross-section of a flap-top embodiment of the interior support anvil-shaped separator taken along the horizontal plane of the interior support anvil-shaped separator where the separator contains one fiber in each of four channels.
FIG. 6A is a cross-section of a cable containing four anvil-shaped separators taken along the horizontal plane of the cable.
FIGS. 6B and 6C illustrate an enlarged detailed version of the closed double-flap, flap-top embodiment of the anvil-shaped separator for the cross-section of a cable containing four anvil-shaped separators taken along the horizontal plane of the cable.
FIG. 7 is a cross-section of a cable containing six anvil-shaped separators taken along the horizontal plane of the cable.
FIG. 8A is a cross-section of an anvil-shaped separator where both outer sharp edged ends of the anvil have been replaced with rounded regions to reduce weight and provide a larger opening for each channel defined by the anvil-shaped separator.
FIG. 8B is also a cross-section of an anvil-shaped separator where both outer sharp edged ends of each anvil section are replaced with rounded regions and each anvil section includes a channel for a drain wire.
FIG. 9A is a cross-section of an anvil-shaped separator where dual lobed anvil sections are minimized in size to provide the greatest possible channel girth and opening while still maintaining an anvil-like shape.
FIG. 9B is also a cross-section of an anvil-shaped separator where dual lobed anvil sections are minimized in size and each dual lobed section includes a channel for a drain wire.
DETAILED DESCRIPTION
The following description will further help to explain the inventive features of the cable and the interior support portion of the cable.
FIG. 1A is a top-right view of one embodiment of this invention. The shown embodiment has an interior support shown as an anvil-shaped separator with flap-tops ( 110 ). The interior support anvil-shaped separator, shown in more detail in FIGS. 3 and 4, runs along the longitudinal length on the cable. The interior support anvil-shaped separator, hereinafter, in the detailed description, referred to as the “anvil-shaped separator”, has a central region ( 112 ) extending along the longitudinal length of the cable. The center region includes a cavity that runs the length of the separator in which a strength member ( 114 ) may be inserted. Channels 120 , 122 , 124 , and 126 extend along the length of the anvil-shaped separator and provide compartments for conductors ( 130 ).
A strength member may be added to the cable. The strength member ( 114 ) in the shown embodiment is located in the central region of the anvil-shaped separator. The strength member runs the longitudinal length of the anvil-shaped separator. The strength member is a solid polyethylene or other suitable plastic, textile (nylon, aramid, etc.), fiberglass flexible or rigid (FGE rod), or metallic material.
Conductors, such as the shown insulated twisted pairs, ( 130 ) are disposed in each channel. The pairs run the longitudinal length of the anvil-shaped separator. While this embodiment depicts one twisted pair per channel, there may be more than one pair per channel. The twisted pairs are insulated with a suitable polymer, copolymer, or dual extruded foamed insulation with solid skin surface. The conductors are those normally used for optical or conventional data transmission. The twisted pairs may be bonded such that the insulation of each conductor is physically or chemically bound in an adhesive fashion, or an external film could be wrapped around each conductor pair to provide the same effect. Although the embodiment utilizes twisted pairs, one could utilize various types of insulated conductors within the anvil-shaped separator channels or cavities.
FIG. 1B is another embodiment that includes grooves both on the exterior surface ( 150 ) of the separator and within the channels ( 152 ) of the separator. The,interior grooves within the channels of this embodiment are specifically designed so that at least a single conductor of a conductor pair can be forced along the inner wall of the groove, thereby allowing for specific spacing that improves electrical properties associated with the conductor or conductor pair.
FIG. 1C is yet another related embodiment that includes the use of an exterior corrugated design ( 160 ) such that the outer surface of the support-separator has external radial grooves along the longitudinal length of the cable. This exterior surface can itself function as a jacket if the fully closed anvil-shaped version of the invention as described above is utilized.
A metal drain wire may be inserted into a specially designated slot ( 140 ). The drain wire functions as a ground or earthing wire.
The anvil-shaped separator may be cabled with a helixed configuration. The helically twisted portions in turn define helically twisted conductor receiving grooves within the channels that accommodate the twisted pairs or individual optical fibers.
The cable ( 200 ), as shown in FIG. 2A is a high performance shielded cable capable of 600 MHz or greater transmission. The cable has an optional outer jacket ( 210 ) that can be polyvinyl chloride or neoprene or a fluoropolymer or a polyolefin with or without halogen free material as required by flammability and electrical specifications as detailed above. Additionally, the jacket may be either corrugated ( 220 ) or smooth/ribbed ( 210 ) depending on the nature of the installation requirements. Mechanical integrity using an outer jacket such as depicted in FIGS. 2A and 2B, may be essential for installation purposes.
FIG. 2B is another embodiment that includes grooves along the interior channels of the separator. The interior grooves within the channels of this embodiment are also specifically designed so that at least a single conductor of a conductor pair can be forced along the inner wall of the groove, thereby allowing for specific spacing that improves electrical properties associated with the conductor or conductor pair.
Over the anvil shaped separator an optional polymer binder sheet or tape ( 230 ) may be used as shown in FIG. 2 C. The binder is wrapped around the anvil shaped separator to enclose the twisted pairs or optical fiber bundles. The binder or tape may include an adhesive to hold an optional laterally wrapped shield. The electromagnetic interference and radio frequency (EMI-RFI) shield is a tape with a foil or metal surface facing towards the interior of the jacket that protects the signals carried by the twisted pairs or fiber cables from electromagnetic or radio frequency distortion. The shield may be composed of a foil and has a belt-like shield that can be forced into a round, smooth shape during manufacture. This taped embodiment with shield may be utilized to control electrical properties with extreme precision. A metal drain wire ( 240 ) may be inserted into a specially designated slot that then can be subsequently wrapped around the shield. The drain wire within the slot runs the length of the cable. The drain wire functions as a ground or earthing wire.
Use of the term “cable covering” refers to a means to insulate and protect the cable. The cable covering being exterior to said anvil member and insulated conductors disposed in grooves provided within the clearance channels. The outer jacket, shield, drain spiral and binder described in the shown embodiment provide an example of an acceptable cable covering. The cable covering, however, may simply include an outer jacket or may include just the exterior surface (corrugated or convoluted with ribbed or smooth surfaces) of the anvil shaped interior support member.
The cable covering may also include a gel filler to fill the void space ( 250 ) between the interior support, twisted pairs and a portion of the cable covering.
The clearance channels formed by the anvil shaped interior support member of the present inventive cable design allows for precise support and placement of the twisted pairs, individual conductors, and optical fibers. The anvil shaped separator will accommodate twisted pairs of varying AWG's and therefore of varying electrical impedance. The unique circular shape of the separator provides a geometry that does not easily crush and allows for maintenance of a cable appearing round in final construction.
The crush resistance of the inventive separator helps preserve the spacing of the twisted pairs, and control twisted pair geometry relative to other cable components. Further, adding a helical twist allows for improving overall electrical performance design capability while preserving the desired geometry.
The optional strength member located in the central region of the anvil shaped separator allows for the displacement of stress loads away from the pairs.
FIG. 3A is a horizontal cross-section of a preferred embodiment of the anvil-shaped separator with dual flaptops. The anvil-shaped separator can be typically approximately 0.210 inches in diameter. It includes four channels ( 300 , 302 , 304 , and 306 ) that are typically approximately 0.0638 to 0.0828 inches in diameter. The channel centers are 90 degrees apart relative to the center of the separator. Each channel is typically approximately 0.005 inches from the channel across from it, and each channel is approximately 0.005-0.011 inches apart from its two nearest-neighboring channels at their closest proximity. Inserted in the channels is one set of twisted pairs ( 310 , 312 , 314 , and 316 ) with the option for adding twisted pairs to each channel denoted by dashed circles. In a preferred embodiment, each channel has typically a 0.037-inch opening along its radial edge that allows for the insertion of the twisted pairs. This embodiment also includes a cavity in the center of the anvil-shaped separator for a strength member ( 320 ). Additionally, there is a slot for a drain or earthing wire ( 330 ).
FIG. 3B is another embodiment of the anvil-shaped separator. The anvil-shaped separator includes a single flap-top ( 340 , 342 , 344 , and 346 ) that is initially in an open position to allow the twisted pairs to be inserted into the channels. In FIG. 3C the flap-tops are in the closed position ( 350 , 352 , 354 , and 356 ) where the flap-top fits into a recessed portion of the separator for closure. The flap-tops are self-sealing when heat and/or pressure is applied, such that elements within the channels can no longer be removed from the separator and such that the channels containing the twisted pairs are enclosed.
FIG. 3D is another embodiment of the anvil-shaped separator. This anvil-shaped separator includes a single flap-top ( 380 , 382 , 384 , and 386 ) that is depicted in the closed position. When in the closed-position, the flap-top overlaps ( 390 ) the outer portion of the separator and has a rounded ending ( 395 ). The amount of overlap required will depend on several design and manufacturing factors and the shown embodiment is only intended as one example of the overlap required. The flap-tops are self-sealing when heat and/or pressure is applied, such that the elements within the channels can no longer be removed or displaced from the separator and such that the channels containing twisted pairs are enclosed.
Another embodiment of FIG. 3 includes all of the aforementioned features of FIG. 3 without the drain wire or drain wire slot, but includes the center hole for strength members. A further embodiment of FIG. 3 includes all the aforementioned features of FIG. 3 without the center hole for strength members and without the drain wire or drain wire slots.
FIG. 4A is another embodiment of the anvil-shaped separator. The anvil-shaped separator includes double flap-tops ( 440 , 442 , 444 , and 446 ) that are initially in an open position to allow the twisted pairs to be inserted into the channels. In FIG. 4B the flap-tops are in the closed position ( 450 , 452 , 454 , and 456 ). The flap-tops are again self-sealing in the presence of heat and/or pressure and the channels containing the twisted pairs are subsequently enclosed. The flap top is shown in more detail in FIG. 4 C. Another embodiment of FIG. 4 includes all of the aforementioned features of FIG. 4 without the drain wire or drain wire slot, but includes the center hole for strength members. A further embodiment of FIG. 4 includes all the aforementioned features of FIG. 4 without the center hole for strength members and without the drain wire or drain wire slot.
The single flap-tops of FIG. 3 ( 350 or 380 for example) and the double flap-top ( 440 ) enclose the wires or cables within channels created by the separator. During manufacturing, the flap-top is in the opened position and closes as either pressure or heat or both are applied (normally through a circular cavity during extrusion). Optionally, a second heating die may be used to ensure closure of the flap-top after initial extrusion of the separator or cable during manufacture. Another possibility is the use of a simple metal ring placed in a proper location that forces the flap-top down during final separator or cable assembly once the conductors have been properly inserted into the channels. The metal ring may be heated to induce proper closure. Other techniques may also be employed as the manufacturing process will vary based on separator and cable requirements (i.e. no. of conductors required, use of grounding wire, alignment within the channels, etc.). In one embodiment (FIG. 3C) the single flap-top ( 360 ) is secured to a recessed portion of one side of an opening of the cavity of the separator ( 365 ), and closure occurs when the unsecured, physically free end is adjoined to and adhered with the other end of the outer surface of the channel wall. In another embodiment the single flap-top ( 390 ) is secured by overlapping and adhering the unsecured end to the outer rounded end surface of the separator ( 395 ), thereby, enclosing the channel. The double-flap top arrangement requires that both flap-top ends physically meet and eventually touch to secure enclosure of the existing cavity ( 460 ) formed by the separator ( 470 ).
FIG. 5 is a cross-section of another embodiment of the flap-top anvil-shaped separator. Each channel is enclosed by double flaps that can be sealed via heat and/or pressure ( 510 , 512 , 514 , and 516 ). Each channel contains at least one fiber ( 520 , 522 , 524 , and 526 ) that runs the length of the cable. More than one fiber may be included in each channel if necessary. The separator also includes a slot for a drain or earthing wire ( 530 ).
FIG. 6A is a cross-section of a cable that contains four anvil-shaped separators ( 600 , 602 , 604 , and 606 ) within a larger anvil-shaped separator ( 610 ). The larger separator contains a cavity in the center of the separator for a strength member ( 620 ). Each of the smaller separators contained within the larger anvil-shaped separator has four channels ( 630 , 632 , 634 , and 636 ). As shown, each of these channels contains a twisted pair within this embodiment ( 640 , 642 , 644 , and 646 ). This embodiment allows for a total of sixteen twisted pairs to be included in one cable. FIGS. 6B and 6C illustrate an enlargement a flaptop configuration used for each of the smaller anvil-shaped separators.
FIG. 7A is a cross-section of a cable that contains six anvil-shaped separators ( 700 , 701 , 702 , 703 , 704 , and 705 ) within a larger anvil-shaped separator ( 710 ). The larger separator contains a cavity in the center of the separator for a strength member ( 720 ). Each of the smaller separators contained within the larger anvil-shaped separator has four channels ( 730 , 732 , 734 , and 736 ). Within each of these channels is one twisted pair ( 740 , 742 , 744 , and 746 ). This embodiment allows sixteen twisted pairs to be included in one cable. FIG. 7 a has the added feature of a wired slot ( 750 ) which can hold a 25-30 th conductor pair.
FIGS. 8A and 8B depict a cross-section and additional embodiment of an anvil-shaped separator which has been substantially trimmed such that the each edged end of each anvil is removed ( 800 and 802 ) to reduce weight resulting in enlarged channel openings ( 804 ). FIG. 8B depicts the cross-section with optional drain wires within each solid and trimmed anvil section ( 810 , 812 , 814 , and 816 ).
FIGS. 9A and 9B are cross-sections and additional embodiments of a separator where the dual lobed ends of the anvil are minimized ( 900 and 902 ) such that an even further reduction in weight, enlarged channel openings ( 904 ) and enlarged channel girth are provided. FIG. 9B includes earthing or drain wire slots ( 910 , 912 , 914 , and 916 ).
It will, of course, be appreciated that the embodiment which has just been described has been given simply by the way of illustration, and the invention is not limited to the precise embodiments described herein; various changes and modifications may be effected by one skilled in the art without departing from the scope or spirit of the invention as defined in the appended claims. | The present invention includes a high performance communications cable that includes core support-separators which define clearance channels to maintain spacing between transmission media or transmission media pairs. The core support-separator can be either interior to a cable jacket or be employed singularly without the benefit of a jacket and extends along the longitudinal length of the communications cable. Alternatively, with no jacket for cable completion, a thin layer of material along the exterior of the support-separator acts as a type of skin for mechanical protection. The core support-separator has a central region that includes flap-tops along the radial edge that are available for partial or complete sealing of the clearance channels during manufacturing operations. The central region may also include a hollow center portion. Each of the defined clearance channels allow for disposal therein of metal conductors and/or optical fibers. | 7 |
[0001] This application claims priority under 35 U.S.C. §119(e) of U.S. Provisional Application No. 60/367,630 entitled “Error Detection and Correction of Data Striped Over Multiple Serial Channels” filed on Mar. 25, 2002 which is herein incorporated by reference, but is not admitted to be prior art.
BACKGROUND
[0002] High-speed store-and-forward devices, such as switches and routers, used in today's communication networks have a large amount of data passing through them. These devices typically include a set of line cards, which perform various operations within the communication networks. Communication between these line cards usually takes place over a backplane, which provides connectivity among the line cards, e.g., via dedicated point-to-point or switched communication paths. With advances in serial communication technologies, the preferred choice for high-speed backplanes today is to use one or more high-speed serial links (channels). High-speed serial data can be carried over either electrical backplanes or optical backplanes. If an optical backplane is used, the transmitting line card must convert electrical signals to optical signals and send the optical signals over fiber, and the destination line card must receive the optical signals from the fiber and reconvert them to electrical signals. The backplane may be used to switch data between line cards or may transport the data without switching. Serializers and deserializers are used, in conjunction with an encoding scheme, such as 8-bit to 10-bit encoding, to create a self-clocked high-speed serial electrical data stream.
BRIEF DESCRIPTION OF THE DRAWINGS
[0003] [0003]FIG. 1 illustrates an exemplary system having multiple line cards connected through serial links over a point-to-point or switched backplane, according to one embodiment;
[0004] [0004]FIGS. 2A and B illustrate exemplary charts explaining how a frame is striped (interleaved) across data channels, according to one embodiment;
[0005] [0005]FIG. 3 illustrates an exemplary transmission module, according to one embodiment;
[0006] [0006]FIG. 4 illustrates an exemplary receiving module, according to one embodiment;
[0007] [0007]FIG. 5 illustrates an exemplary flowchart of the processing of a frame received over a plurality of channels, according to one embodiment;
[0008] [0008]FIG. 6 illustrates an exemplary parity byte calculation, according to one embodiment;
[0009] [0009]FIG. 7 illustrates an exemplary transmission module, according to one embodiment;
[0010] [0010]FIG. 8 illustrates an exemplary receiving module, according to one embodiment;
[0011] [0011]FIGS. 9A and B illustrate an exemplary flowchart of the processing of a frame received over a plurality of channels, according to one embodiment; and
[0012] [0012]FIG. 10 illustrates an exemplary frame and stripe format, according to one embodiment.
DETAILED DESCRIPTION
[0013] [0013]FIG. 1 illustrates an exemplary system 100 for transmitting data amongst various sources and destinations. The system may transmit the data using any number of protocols including Asynchronous Transfer Mode (ATM), Internet Protocol (IP), and Time Division Multiplexing (TDM). The data may be sent in variable length or fixed length blocks, such as cells, packets or frames. The communication lines used to transmit data may be fiber, copper, or other mediums. The system includes at least one store-and forward device 105 , such as a router or packet switch. The store-and-forward device 105 includes multiple line cards connected together through serial links over a point-to-point or switched backplane. A plurality of ingress modules 110 are connected through a backplane 120 to a plurality of egress modules 130 . The backplane 120 may be electrical or optical. The ingress modules 110 and the egress modules 130 are typically two sides of a line card. The line cards may be Ethernet (e.g., Gigabit, 10 Base T), ATM, Fibre channel, Synchronous Optical Network (SONET), and Synchronous Digital Hierarchy (SDH), amongst others. According to one embodiment, the data transmitted over the backplane is broken up into segments (e.g., frames). In a packet switch, the segment includes a single packet or a set of packets sent from a source line card to destination line card. Each segment has a defined maximum length which does not exceed a predetermined maximum length.
[0014] In order to meet bandwidth requirements the data (e.g., frames) being transmitted from one card to another card over the backplane is striped over multiple high-speed serial channels N between the cards. Striping is accomplished by breaking the data up and transmitting portions of the data over each of the N channels. For example, if the frame to be striped had W bytes, each channel would transmit W/N bytes. According to one embodiment, a first byte (e.g., byte 0) is transmitted over a first channel (e.g., channel 0), a second byte (e.g., byte 1) is transmitted over a second channel (e.g., channel 1), and so on until an N th byte (e.g., byte N−1) is transmitted over the N th channel (e.g., channel N−1). Once each channel has transmitted a byte, the next byte (e.g., byte N) is transmitted on the first channel (e.g., channel 0). The process is repeated until all W bytes in the frame are transmitted. One way to look at this is that the data is broken up into W/N groups, with each group having N bytes. One byte (of the N bytes) from each group is then transmitted to each data channel (of the N data channels). The bytes belonging to a frame that travel on one specific channel is called a stripe. For example, the sequence of bytes 0, N, 2N, 3N, etc. would make up stripe 0 (e.g., the part of the frame traveling on channel 0). Note that some channels may have less than W/N bytes (or may have no data) and that the last group may have less than N bytes.
[0015] [0015]FIG. 2A illustrates an exemplary chart explaining how a frame including W bytes is striped (interleaved) across N data channels. The first column lists the byte number (0 to W−1), the second column lists the data channel number (0 to N−1) and the third column the group number (0 to (W/N)−1). As illustrated, bytes 0 to N−1 are striped over data channels 0 to N−1 to form a first group (group 0); bytes N to 2N−1 are striped over data channels 0 to N−1 to form a second group (group 1); and so on until bytes ((W/N)−1)N to W−1 are striped over data channels 0 to N−1 to form a last group (group (W/N)−1).
[0016] [0016]FIG. 2B illustrates an exemplary chart explaining how a frame including 26 bytes is striped (interleaved) across 6 data channels. This example would create 4 groups having 6 bytes each and a fifth group having two bytes. As illustrated, the first six bytes (bytes 0 to 5) are striped over each data channel (channels 0 to 5) to form a first group (group 0); the next six bytes (bytes 6 to 11) are striped over each data channel (channels 0 to 5) to form a second group (group 1); and so on until the last two bytes (bytes 24-25) are striped over the first two data channels (channels 0 and 1) to form a last group (group 4).
[0017] The various embodiments are in no way intended to be limited to the striping assignments discussed above. Rather, the bytes can be transmitted over the channels in any order. For example, byte 0 could be assigned to channel (N−1), byte 1 could be assigned to channel (N−2) and so on. Moreover, the various embodiments are not limited to transmitting the data byte by byte. The data could be transmitted bit by bit, sector by sector, block of bytes by block of bytes, or block of bits by block of bits, where a block can be defined by a user. Furthermore, the various embodiments are not limited to receiving frames that are organized as W bytes. Rather the frames could be organized by bits, sectors, or other ways.
[0018] Before transmission, a cyclic redundancy code (CRC) is computed for the frame. The CRC is inserted at the end of the frame and is transmitted along with the frame (data). Also, a separate CRC is computed for each stripe and is sent as part of the stripe.
[0019] [0019]FIG. 3 illustrates an exemplary transmission module 300 , according to one embodiment. The transmission module 300 receives an input frame that is W bytes long at a CRC generator 310 that generates a CRC for the entire frame. The entire frame including the CRC is provided to a striper 320 . The striper 320 divides the W bytes into N groups and selects the channel for each group to be transmitted over. That is, one group will be transmitted over each of the N channels. A CRC is generated for each stripe and is inserted at the end of the stripe by a CRC module 330 . The stripe and the associated CRC for each channel are then provided to a transmitter 340 for transmitting over the backplane. There are a total of N transmitters 340 , one for each data channel. In the event of channel failures (discussed later) the transmission module can be reconfigured to stripe the data over fewer channels. Up to P channels can be configured out of the system so that the data can be striped over a minimum of N-P channels.
[0020] The data sent over each channel (stripe) is received and buffered and the frame is recreated. A CRC is computed for the entire received frame and compared to the CRC that was transmitted with the frame in order to check for errors in the received frame. In addition, a CRC is computed for each channel and compared to the transmitted CRC for the channel to check for errors in the strip. If the computed CRC does not match with the transmitted CRC at the end of the stripe, the data within the stripe is deemed to be in error. The CRC error indication for each channel is ORed with an error signal from a corresponding physical receiver device. The physical receiver device indicates errors such as loss of signal etc. The ORed error signal is referred to as a channel error. If there is an error for the overall frame and/or one or more channel errors the frame is discarded.
[0021] Each channel is provided with a channel-specific error counter and an associated threshold register. When any channel-specific error count exceeds the threshold, there is a provision for an interrupt to be issued to the processor (or custom hardware) controlling the system. The software (or custom hardware) would set the value of the threshold such that in a given interval, if the number of errors exceed the value specified in the threshold register, it is likely that the channel has a permanent hardware problem. The system may then be shut down to replace one or more components to restore full throughput. If the error count does not exceed the threshold in the specified interval, it is likely that any errors that occurred were random in nature and may be ignored. At the end of each specified interval, the channel-specific error counts are reset. Note that the software (or custom hardware), needs to keep a rolling average of the per-channel error count.
[0022] Fixing a channel may cause down time on the system. According to one embodiment, the CPU (custom hardware) may reconfigure the system to stripe the data over fewer channels (N−1 channels, N−2 channels, etc.). In general, the data can be striped over any number of channels in the range N-P (minimum) to N (maximum). This allows for P channels to fail, and still have data transmission over the backplane and through the switching chips to the destination line card, albeit at a reduced bandwidth. The value of P is determined by the reduction of throughput that can be tolerated.
[0023] [0023]FIG. 4 illustrates an exemplary receive module 400 , according to one embodiment. The receive module 400 includes N serial channel receivers 410 for receiving and buffering data over the N data channels. A CRC module 420 generates a CRC for each data channel (stripe). The stripes are provided to a destriper 430 that takes the N channels and converts it back into a W byte (or bit, etc.) frame. The destriper 430 forwards the frame to a CRC computation module 440 that computes the CRC for the entire frame and then compares the generated frame CRC to the transmitted frame CRC, and the generated stripe CRCs to the transmitted stripe CRCs to determine errors. Errors in any channel are recorded and compared to an error threshold. If the channel exceeds the error threshold it is configured out of the system until it can be repaired. Up to P channels can be configured out of the system so that the striped data can be transmitted using as little as N-P channels (minimum number of channels).
[0024] [0024]FIG. 5 illustrates an exemplary flowchart of the processing of a frame received over a plurality of channels. Initially, the received frame is checked for an error indicated by the frame-level CRC ( 500 ). If there is no error in the frame level CRC ( 500 No), then each individual stripe is checked for errors based on the CRC or an error indication from the physical receiver device ( 505 ). If there is no error in any channel ( 505 No), then the frame is declared good and is sent out for further processing ( 510 ). If there are one or more channels with errors ( 505 Yes), then the error is an uncorrectable error. The frame is discarded and the corresponding per-channel error counters are incremented ( 515 ).
[0025] If there was a frame level CRC error ( 500 Yes), then a determination is made as to whether there are any channel errors ( 520 ). If there are no channel errors ( 520 No), then the frame is discarded and the frame error count is incremented ( 525 ). If there were channel errors ( 520 Yes) then the frame is discarded, the frame error count is incremented, and the channel error count(s) are incremented ( 530 ). After any incrementing of channel errors ( 515 , 525 , 530 ) the error count of each channel is compared to error thresholds ( 535 ). If the threshold is not exceeded ( 535 No) for every channel then the process is complete. If the threshold is exceeded for at least one channel ( 535 Yes) an interrupt is issued to a CPU, or custom hardware ( 540 ). The CPU (custom hardware) receives the interrupt indicating that the threshold(s) has been exceeded, and makes a determination as to whether there are enough usable channels remaining to support the system ( 545 ). That is, if we take the faulty channel out of service are the number of channels remaining at least equal to the minimum number of channels (N-P) required to meet the bandwidth requirements of the system? If the number of channels remaining after deactivating the faulty channels is less than the minimum number of channels ( 545 No), then the system is shut down for servicing ( 550 ). If the number of channels remaining after deactivating the faulty channels is still at least equal to the minimum number of channels ( 545 Yes), then the system is reconfigured to utilize only working channels ( 555 ).
[0026] The exemplary process flow described above is not the only embodiment but is merely an example. Numerous modifications could be made to the process flow (e.g., the order could be rearranged and/or individual operations could be combined or split apart).
[0027] Discarding an entire frame because of a single channel failure is not desirable. This situation may be perpetuated if multiple channels continually fail at different times, with no channel failing enough to exceed the threshold. In this case numerous frames are discarded, but none of the channels is deactivated. According to one embodiment, the CPU (custom hardware) may switch from a graceful degradation mode (the mode described above where if a channel(s) has multiple errors that exceed a threshold they can be configured out of the system) to a single channel error correction mode. The single channel error correction mode allows a single channel error to be corrected.
[0028] In this embodiment, the N serial channels are divided into M data channels and K parity channels. The parity channels are used to send parity information associated with the data being sent. If the data is being striped by bytes then the parity will be transmitted by bytes as well. The parity bytes (or other grouping) are used for correction of errors. The M data channels are divided into groups and each group is associated with a parity channel. As there are K parity channels it follows that there will be K groups of data channels and each group will have M/K channels. For each byte within a group (e.g., M/K channels) there is an associated parity byte in the corresponding parity channel. In a preferred embodiment, each parity byte is generated by XORing (that is, computing the logical Exclusive-OR operation of) each bit of each associated byte in the data channels within the group. For example, bit 0 of the parity byte is the XOR of the bits in position zero of all the bytes in that group, bit 1 is the XOR of the bits in position one of all the bytes in that group, and so on.
[0029] [0029]FIG. 6 illustrates an exemplary parity byte calculation for a group of 3 data channels that are utilized to transmit a plurality of bytes. The parity byte is calculated by XORing each bit of the data bytes. The various embodiments are in no way intended to be limited to generating the parity data by XORing associated bits together. Rather, there are multiple methods for generating parity data (e.g., bits, bytes, etc.).
[0030] If there is channel error on only a single data channel (e.g., error is confined to a single stripe) associated with a group of channels, the data for that channel (stripe) can be recovered. The data for the channel is recovered by XORing the data from all the other channels (data and parity) in the group. The recovered data replaces the received data for that channel (stripe). Once the data is recovered for the errored channel (stripe), the frame is reassembled from all the received channels (stripes) and the corrected channel (stripe). A second CRC check is then performed on the frame. If this CRC check passes, the entire frame is deemed error-free and accepted by the receiver. An error count is incremented for the data channel having the failure. If the error count exceeds some predefined threshold, action may be taken to fix the channel (discussed later).
[0031] If there is only a single channel error on a parity channel associated with a group of channels, the received data within the group is processed normally (as if there were no error). An error count is incremented for the parity channel having the failure. If the error count exceeds some predefined threshold, action may be taken to fix the channel (discussed later).
[0032] It should be noted that if there is a channel error (data or parity as discussed above) that there should also be a frame level error. If there is a channel error but no frame level error the frame will be discarded and the channel error count is incremented.
[0033] If errors are detected in more than one channel (whether data or parity) in a group, the error is uncorrectable. The frame is discarded and a frame error counters are incremented. If the error count exceeds some predefined threshold, action may be taken to fix the channel.
[0034] If the frame level CRC indicates an error, but there are no channel errors detected in any group, then it is an uncorrectable error. The frame is discarded and a frame error counter is incremented.
[0035] The above descriptions apply for each group of channels. The actions in one group are independent of the actions required (or taken) in other groups.
[0036] [0036]FIG. 7 illustrates an exemplary transmission module 700 , according to one embodiment. The transmission module 700 is much like the transmission module 300 of FIG. 3 with the exception that the N serial channels are divided into M data channels and K parity channels. A CRC generator 710 receives a frame and generates a CRC for the entire frame. The entire frame including the CRC is provided to a striper 720 . The striper 720 divides the frame into M groups and selects the channel for each group to be transmitted over. A CRC is generated for each stripe and is inserted at the end of the stripe by a CRC module 730 . The stripe and the associated CRC for each channel are then provided to a transmitter 740 for transmitting over the backplane. Each parity channel is associated with a group of M/K data channels. The M/K data channels associated with each parity channel are provided to a parity generator 750 that generates the parity data associated with the group of data channels. As previously mentioned, if the data channels are transmitting data byte by byte the parity data will be a parity byte. In a preferred embodiment, the parity generator 750 is an XOR gate for each bit of the data being transmitted at a time. The XOR gate receives an associated bit from each of the group of M/K data channels. A CRC is generated for each parity channel stripe and is inserted at the end of the parity stripe by a CRC module 760 . The parity stripe and the associated CRC for each parity channel are then provided to a transmitter 770 for transmitting over the backplane.
[0037] It should be noted that the transmitters 740 and the transmitters 770 , as well as the CRC modules 730 and the CRC modules 760 , are illustrated separately for convenience of pointing out the difference between the parity channels and the data channels. However, it should in no way be construed to require different CRC modules and transmitters for parity channels and data channels. Rather, the CRC modules and the transmitters could be the same. In fact, according to one embodiment, the transmission module 700 can easily be reconfigured to have more data channels or more parity channels.
[0038] [0038]FIG. 8 illustrates an exemplary receive module 800 , according to one embodiment. The receive module 800 is much like the receive module 400 of FIG. 4 with the exception that parity bits are received and used for regeneration (correction) of errored stripes. The receive module 800 includes M serial channel receivers 810 for receiving and buffering data over the M data channels. A CRC module 820 generates a CRC for each data channel (stripe). The stripes are provided to a destriper 830 that takes the M channels and converts it back into a frame. The destriper 830 forwards the frame to a CRC computation module 840 that computes the CRC for the entire frame and then compares the generated frame CRC to the transmitted frame CRC, and the generated stripe CRCs to the transmitted stripe CRCs to determine errors. The receive module 800 also includes K serial channel receivers 850 for receiving parity data. A CRC module 860 generates a CRC for each parity channel (stripe). Each parity channel and the data channels that are associated with the parity channel as part of a group, are provided to error correction modules 870 . There is one error correction module 870 for each of the M/K groups. The error correction modules can recreate data lost on an individual channel within a group. As previously discussed, the data can be recreated by XORing all of the other channels (data and parity) within the group. Accordingly, in a preferred embodiment, the error correction modules 870 are XOR gates. The error correction modules 870 provide the corrected data channels to the destriper 830 .
[0039] It should be noted that the receivers 810 and the receivers 850 , as well as the CRC modules 820 and the CRC modules 860 , are illustrated separately for convenience of pointing out the difference between the parity channels and the data channels. However, it should in no way be construed to require different receivers and CRC modules for parity channels and data channels. Rather, the receivers and CRC modules could be the same type of receivers. In fact, according to one embodiment, the receiver module 800 can easily be reconfigured to have more data channels or more parity channels.
[0040] [0040]FIGS. 9A & B illustrate an exemplary flowchart of the processing of a frame received over a plurality of channels. The flowchart of FIGS. 9A & B is similar to the flowchart of FIG. 5 with the exception that a switch to the single channel error correction mode (described above) from the graceful degradation mode (described above) is possible. The mode of the system may be switched at any point in time either automatically or by an operator. One possible occasion for the switch in mode would be the case where the error threshold has not been exceeded for any particular channel but that there have been multiple single channel failures causing multiple frames to be discarded. In this case the system could reconfigure itself to include parity channels (thus reducing the bandwidth available for the data) so that the errors could be self-correcting.
[0041] As previously mentioned, errors within a single channel per group can be corrected in the single channel error correction mode. Thus, the process will require a determination of the mode of the system. Referring to FIGS. 9A and B, the channel error determination ( 520 ) is modified to be a determination as to whether there was a single channel error ( 900 ). If the errors were not limited to a single channel error ( 900 No), the frame is discarded ( 905 ). Also, the frame error count is incremented and the channel error counts for the errored channels are incremented ( 905 ). If the error was limited to a single channel error ( 900 Yes), a determination is made as to whether the system is in single-channel error correction mode ( 910 ). If it is determined that the system is not in single channel error correction mode ( 910 No) the frame is discarded, the frame error count is incremented and the channel error count for the errored channel is incremented ( 920 ). If the errors were limited to a single channel per group ( 910 Yes), a determination is made as to whether the channel having the error is the parity channel ( 930 ). If the channel error was not in the parity channel ( 930 No), the data is the channel is recreated (corrected) by XORing all the other stripes within that group, the frame is generated using the corrected stripe, the frame is sent out, and the channel error count for the errored channel is incremented ( 940 ). If the channel error was in the parity channel ( 930 Yes), the frame is sent out, and the parity channel error count is incremented ( 950 ).
[0042] After any incrementing of channel errors, whether the frames were discarded ( 920 , 940 ) or the frames were transmitted 950 , the error count is compared to the threshold ( 535 ) and if exceeded the CPU receives an interrupt. However, as the single channel error correction mode cannot deactivate and reconfigure channels a determination will have to be made as to which mode the system is in before proceeding. Accordingly, after the CPU (custom hardware) receives an interrupt ( 540 ) indicating that a threshold(s) has been exceeded a determination will be made as to whether the system is in graceful degradation mode ( 960 ). If the system is not in graceful degradation mode ( 960 No), the CPU (custom hardware) will perform the necessary actions ( 970 ). The necessary actions may be to shut down and repair the system now, tag the system for shut down/repair in the future, or switch to graceful degradation mode. If the system was in graceful degradation mode ( 960 Yes), the system proceeds to determine if the number of usable channels is sufficient 545 .
[0043] According to one embodiment, there is also a provision for test data to be sent over one or more channels. Errors detected on the received data are recorded per-channel. This can be used by the software (or custom hardware) to test individual channels before deciding the number of channels to use, or as a periodic self-diagnostic feature.
[0044] The exemplary process flow described above is not the only embodiment but is merely an example. Numerous modifications could be made to the process flow (e.g., the order could be rearranged and/or individual operations could be combined or split apart).
[0045] According to another embodiment, the system may act in both the single channel error correction mode and the graceful degradation mode at the same time. This embodiment is similar to the embodiment of FIGS. 9A and B with the exception that the graceful degradation determination 960 and associated perform action 970 , as well as single channel error correction determination 910 and associated discard frame 920 are no longer required. The system will utilize both data and parity channels so that single channel error corrections can be made. In the event that one or more of the channels exceed the associated thresholds 535 , the CPU (custom hardware) will make a determination if there are sufficient channels available to deactivate the channel or channels 545 . In this embodiment, the determination is not just made on data channels as in the embodiment of FIGS. 9A and B (at least N-P channels). In this embodiment, a determination will have to be made as to whether enough data channels are available with enough associated parity channels to be able to handle single channel error detection. Therefore a minimum number of data channels and associated parity channels need to be defined.
[0046] According to one embodiment, it would be possible to continue processing if there were channels to support the data but not the parity. However, the continued processing would be with limited or no single error correction. If the determination is that enough channels do not exist ( 545 No) then the system is shut down for servicing ( 550 ). If the determination is made that there are enough channels available, the system is reconfigured to use only the working channels ( 555 ).
[0047] [0047]FIG. 10 illustrates an exemplary frame and stripe format. In this example, high speed serial electrical channels are used over a backplane, and switched using a crossbar. There are total of eight serial channels with seven channels used for data and one channel used for parity. All seven data channels belong to one group so that only a single parity channel is required to provide error correction for the seven data channels. The encoding scheme used for framing is the industry-standard 8-bit to 10-bit encoding. It provides a “Start of Frame Delimiter” (SFD) symbol, an “End of Frame Delimiter” (EFD) symbol, and an “Idle Character” symbol. The input data 1000 is broken into frames, and each frame is appended with a frame-level CRC 1010 . The frame-level CRC 1010 is computed over all the data bytes (or bits, etc.) of the frame. The data is striped over the seven data channels 1020 , byte by byte. The data can be striped across the channels in other manners, such as bit by bit or group by group. A parity channel 1030 transmits parity data for the group which is the XOR of all the data from the seven data channels. According to a preferred embodiment, the parity data is derived by the bit-wise XOR of the corresponding bytes of each of the seven data channels.
[0048] Each of the channels initially transmits a first stripe for the frame 1040 that is the start of frame symbol. This is followed by the data stripe (data for the seven data channels 1020 and parity data for the parity channel 1030 ) 1050 . A last data stripe 1060 is the CRC computed for each stripe. A last stripe for the frame 1070 is the end of frame symbol. If only a single channel fails, the channel can be recreated (fixed) by XORing all the other channels in the group. If one of the channels records enough errors to cross the threshold level, the system could either shut down for servicing (now or later) or could reconfigure itself to a graceful degradation mode in which case that channel would be reconfigured out of the system and the data would be transmitted over the remaining channels.
[0049] According to an embodiment in which the system can be reconfigured between single channel error correction mode and graceful degradation mode, if a single channel failed once the system was reconfigured to remove the channel (whether a data channel or the parity channel) the data would continue be transmitted over seven channels but would have no parity channel and thus no error correction.
[0050] According to an embodiment in which the system supports both single channel error correction mode and graceful degradation mode, the system can continue to correct errors while at the same time reconfiguring to deactivate faulty channels. For example, if a data channel failed the data could be striped over the remaining six data channels and the parity channel could continue be used for error correction. However, if the system needed at least 6 data channels to meet bandwidth requirements if a second channel failed the parity channel would have to be deactivated which would eliminate the error correction capability at that point.
[0051] Although the detailed description has been illustrated by reference to specific embodiments, various changes and modifications may be made. Reference in the specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of the phrase “in one embodiment” appearing in various places throughout the specification are not necessarily all referring to the same embodiment.
[0052] Different implementations may feature different combinations of hardware, firmware, and/or software. For example, some implementations feature computer program products disposed on computer readable mediums. The programs include instructions for causing processors to perform techniques described above.
[0053] The various embodiments are intended to be protected broadly within the spirit and scope of the appended claims. | In general, in one aspect, the disclosure describes an apparatus that includes a transmission module to split a data segment into a plurality of data stripes and transmit each data strip over an associated serial channel, a reception module to receive the plurality of data stripes over the associated serial channels and track a number of errors per channel, and a controller to deactivate a serial channel and reconfigure said transmission module and said reception module to utilize remaining data channels for striping data if the number of errors in the serial channel exceeds a threshold. | 7 |
TO RELATED APPLICATION
Application Ser. No. 361,333, filed May 17, 1973, U.S. Pat. No. 3,956,167, entitled LIQUID CRYSTAL COMPOSITION AND DEVICES, Chan S. Oh.
Application Ser. No. 446,807 filed concurrently herewith, now abandoned, entitled FIELD EFFECT LIQUID CRYSTAL COMPOSITIONS, Chan S. Oh.
FIELD OF THE INVENTION
This invention relates to liquid crystalline materials of organic compounds, more specifically, nematic liquid crystals suitable for display device applications. Preferably, the display devices are operable within wide temperature range -- room temperature being in the middle of the range.
BACKGROUND OF THE INVENTION
There are two kinds of nematic liquid crystals; negative dielectric anisotropy nematic material and positive dielectric anisotropy nematic material. The former class of materials undergoes a dynamic scattering mode electro-optic phenomena above certain threshold voltage. In this class of material, the dielectric constant component parallel to the unique axis is smaller than the perpendicular component, thus its dielectric anisotropy is negative. In the second class of nematic liquid crystals, the dielectric constant component parallel to the unique axis is substantially larger than the perpendicular component, hence its dielectric anisotropy is positive. This latter class of materials does not undergo the dynamic scattering mode, instead will undergo dielectric realignment above a certain threshold electric or magnetic field. Thus the materials are field sensitive and its electro-optic phenomena is referred to as "Field Effect" phenomena.
The chemistry and certain of the physical and structural properties of liquid crystals have been studied (References 1-7).
Early liquid crystal chemists synthesized p-ethoxybenzylidene-p'-aminobenzonitrile. Castellano et al (Reference 10) continued the synthetic works on these compounds:
P-N-BUTOXYBENZYLIDENE-P'-AMINOBENZONITRILE,
P-N-HEXOXYBENZYLIDENE-P'-AMINOBENZONITRILE
P-N-HEXANOYLOXYBENZYLIDENE-P'-AMINOBENZONITRILE, AND
P-N-OCTANOYLOXYBENZYLIDENE-P'-AMINOBENZONITRILE.
All of these compounds exist as liquid crystals only at elevated temperatures and exhibit positive dielectric anistropy. Castellano et al found that some ternary mixtures among those compounds gave mixed liquid crystal which is stable at room temperature for extended periods of time. Some pleochroic dyes dissolved in those mixtures exhibited field tunable optical color filters.
Helfrich published a new electro-optic effect, commonly referred to as twisted nematics. He utilized a positive dielectric anisotropy nematic material, and as an example, he utilized a ternary mixture of Castellano's material. The most significant point of his experiment was that the display device can be operated at relatively lower voltages, e.g., 2-7 volts AC or DC. The electro-optic effect is based on the dielectric realignment, thus no dopants are necessary and high purity liquid crystal can be utilized, which is desirable and which will ensure the longevity of the operational life of the display. In addition, electric current flow is minimal (2-3 orders of magnitude lower than those commonly found in dynamic scattering mode), which minimizes any adverse electro-chemical reaction at the liquid crystal-electrode interface. He took advantage of another unique physical characteristic of nematic liquid crystal; due to the crystalline properties of liquid crystal, the molecules tend to associate into a directional pattern on a given substrate. This phenomena has been called "alignment". It was earlier found that if a pair of clear substrates, such as a microscope slide glass, are "rubbed" with dry cotton swab unidirectionally, and a few drops of liquid crystal is enclosed between thus prepared glass plates with their rubbed surfaces in direct contact with liquid crystal, the resultant thin film of liquid crystal exhibited so called "homogeneous" alignment. Under this condition, the rod-shaped liquid crystal molecules laid down on the surface with their major molecular axes parallel to the rubbing direction. The liquid crystal molecules in the bulk also followed parallel to those at the surface by their lateral attraction. The thus obtained liquid crystal medium behaves like a giant single crystal with its unique crystal axis parallel to the rubbing direction, and many physical and optical properties parallel and perpendicular to this unique axis were different.
Now, if the two glass plates are at right angle (90°) to each other so that the rubbed direction at the inner surface of the top plate and the rubbed direction of the bottom plate makes right angle; and if a nematic liquid crystal is introduced in the thus prepared cell, a unique optical medium is obtained.
(Since this original work, many new techniques have been developed in obtaining the "Rubbing Effects", which are more amenable to manufacturing processes. Other cellulosics, synthetic or natural products, can be used instead of cotton swab. Permanently etched "micro-grooves", either by fine powder of abrasive materials, like diamond dust, or by photoetching, of the substrate give the same rubbing effects. More recently, some inorganic materials have been vacuum deposited at an oblique angle on the substrate, and have yielded excellent homogeneous alignment.)
The detailed electro-optical effects of the above "Twisted" optical medium, occurred in the following manner. As usual, the molecules at the immediate surfaces of the top and bottom plates will lie down with their major molecular axes parallel to the respective rubbing directions; however, since these directions are at 90°, with respect to each other the liquid crystal molecules in the bulk will tend, through their lateral interactions, to be conformed to the given environment. Thus the major molecular axis of the liquid crystal molecules will assume a helicoidal configuration between the top and bottom plates.
One of the most important physical properties of the above described optical medium is its ability to rotate plane polarized light by 90° as the polarized light traverses through the medium. Of course, if the imposed angle is other than 90°, the angle of rotation of the plane polarized light will vary accordingly and angles other than 90° are also found to be useful for display device fabrications.
If a linear polarizer is placed under the bottom plate, holding the direction of the polarization parallel to the rubbing direction of the bottom plate, and a flux of white light hits the bottom polarizer and is linearly polarized, it enters the liquid crystal medium without attenuation. But as the light wave front traverses the "twisted" liquid crystal medium, it follows the "directors" of the helically arranged nematic molecules and the emerging light is polarized perpendicularly with respect to the direction of polarization of the entering light. If a second polarizer is placed on top of the top plate of the cell, with its polarizing direction parallel to that of the polarizer placed at the bottom of the cell, the emerging light will be completely "extinguished". (Cells of this type have been described, see References 8-14.)
Electro-optic cells can be fabricated using a pair of glass plates with inner surfaces coated with transparent conductive film and filling the cell with a positive dielectric anisotropy nematic liquid crystal after proper surface treatment. In its quiescent state ("OFF" state), without electric power, the display appears dark in color. If an electric power of few volts (AC or DC) is applied across the two plates, the cell will appear transparent; in other words, the liquid crystal medium has lost its polarizing effect completely, thus the linearly polarized light from the bottom polarizer travels straight through the liquid crystal medium and the top polarizer without attenuation. The liquid crystal molecules undergo the dielectric realignment under the influence of the applied electric field, all the dipoles being aligned along with the field direction, which effectively destroys the quiescent helicoidal molecular arrangements. The liquid crystal layer now is called "uniaxial negative" and its optic axis (unique axis) is perpendicular to the cell surfaces. If the imposed electric potential is removed, the liquid crystal relaxes back to its helicoidal arrangement and its polarizing ability is attained quickly. Thus, the liquid crystal medium behaves like an electric controlled "light valve".
It is possible to fabricate various kinds of display devices, transmissive and reflective types. In the former case, the active segments appear clear on black background if the two polaroids are parallel and black segments on white background can be obtained with perpendicularly positioned polaroids. Ambient light source is enough to visualize, but back-lighting may be added to the display device to enhance the viewability. Reflective type displays, such as minimum power draining wrist watch displays, can utilize diffusive reflectors at the bottom of the display. The active segments will appear similar to those of transmissive mode displays, depending upon the relative position of the two polaroids. (See references 8-14 for descriptions of various liquid crystal devices of the type in which the materials of this invention are useful.)
There are several positive dielectric anisotropy nematic materials potentially useful for display devices. Castellano, Reference 13, described a homologous series of p-alkoxy and p-acyloxy-benzylidene-p'-amino-benzonitriles. These materials were used only for the electric field induced color filters but twisted nematics for field effect display devices have been described using positive dielectric anisotropy nematic materials as shown below: ##STR1## The binary mixtures A+B and C+D yield mixed nematic liquid crystals which are suitable for field effect display elements. Threshold voltage of 0.9V was obtained in the case of mixture A+B. The mixture A+B has another advantage; that is, this mixture is resistant to the chemical degradation due to moisture and is colorless, while the mixture C+D, and any other Schiff base materials, are very slightly yellow and sensitive to moisture contamination. More recently, another class of non-Schiff Base nematic materials, biphenyl derivatives, and mixtures of them were found to be useful as field effect display element.
In spite of the number of materials described, there are some more desirable material characteristics to be improved. These desirable properties include:
1. The nematic liquid crystal or mixtures should have wide nematic temperature range, including room temperature, preferably with room temperature in the middle of the range.
2. The nematic crystal or mixtures should have positive dielectric anisotropy of substantial magnitude, such that the resultant twisted nematic display device can be operated at commonly available driving voltages.
3. The electro-optic effect should start to appear at a definite voltage (Vth, threshold voltage) and reach its maximum at a slightly higher voltage (Vsat, saturation voltage) then the threshold value. Depending upon material system, Vth and Vsat change with different magnitudes by temperature changes of the surrounding environments, but these changes of Vth and Vsat should be minimal.
4. V - Vsat - Vth values for different materials indicate the sensitivity with which the materials respond to the applied voltage change. In order to obtain clear-cut electro-optic effect, which maximizes the multiplex capability of the display device, V should be minimum.
5. The materials should be chemically resistant to oxygen, moisture, ultraviolet light or electric current.
In addition, it has now been discovered that potentially serious shortcomings are inherent in the use of Schiff base materials as nematic liquid crystals. Such materials have very desirable electro-optic characteristics; however, they tend to be unstable under some conditions. Extreme care to avoid oxygen and moisture are required to obtain long term high stability liquid crystal components, and even the best practical care may not ensure a long life component. Schiff bases tend to decompose irreversibly and lose their electro-optic characteristics and, consequently, are not satisfactory materials in some liquid crystal devices. It is, therefore, desirable to provide liquid crystal materials which are less sensitive to degradation and which can be restored to a good nematic liquid crystal condition.
DESCRIPTION OF THE INVENTION
The nematic materials basically consist of single, binary, or ternary mixtures of non-Schiff base positive dielectric anisotropy material(s) and a suitable non-Schiff base negative dielectric anisotropy nematic material, which may also be of multiple components which serves as solvent. The latter materials have wide nematic temperature range including room temperature in the middle of the range, have low viscosity, and are preferably chemically stable.
It has been found that these non-Schiff base nematic solvent materials may be negative dielectric anisotropy materials and can be used without sacrificing the positive dielectric anisotropy materials and can be used without sacrificing the positive dielectric anisotropy of the solute materials to a substantial degree, in such a manner that the resultant mixtures exhibited excellent electro-optic effect as twisted nematic display element.
Many positive dielectric anisotropy materials may be used as solute material. They may be enantiotropic (or monotropic) liquid crystals or molecules structurally and chemically compatible with the solvent nematic liquid crystal. Some structurally compatible molecules readily dissolve into nematic liquid crystal without destroying nematic phase; that is, without lowering the nematicisotropic transition temperature of the solvent nematic liquid crystal substantially, but these solute molecules can modify the physical properties of the solvent nematic material. The preferred solute materials contain a cyano functional group directly linked to aromatic ring, and at least two benzene rings which are connected by a double bond. These molecules are essentially rod shaped, relatively rigid, and compatible with the preferred solvent nematic materials, which will be elaborated in detail in the following paragraphs. The cyano functional groups render these types of molecules with positive dielectric anisotropy. These non-Schiff base materials can be intermixed among them without adverse chemical reactions or loss of dielectric anistropy. Thus, these solute molecules of enantiotropic, monotropic liquid crystals or nonliquid crystalline nature, or intermixtures between them, can be dissolved in appropriate nematic solvents and the resultant mixture still has useful nematic temperature ranges and desired positive dielectric anisotropy suitable as display device elements. All the known positive dielectric anisotropy nematic liquid crystals, including the above listed materials and intermixtures thereof, do not have desirable nematic temperature ranges. Thus, the nematic solvents are utilized mainly to reduce the crystal (or solid) nematic transition temperature, and to reduce the viscosity, which will modify the response times.
Many negative nematic liquid crystals can be used as nematic solvents. Unfortunately, many of the well known nematic liquid crystals or mixtures with desirable temperature range are negative dielectric anistropy materials. As it was discussed in the introductory part, oriented liquid crystal materials, e.g., uniformly oriented nematic film being a single giant crystal, have two dielectric constants which are different in magnitude depending upon different materials. The dielectric constant perpendicular to the unique axis of the nematic crystal film (usually the unique axis is almost parallel to the longer axis of the aligned nematic molecules) is designated ε.sub.|, and ε.sub.∥ designates the dielectric constant parallel to the unique axis. In a given nematic material, if its Δε = ε.sub.∥ - ε.sub.|< 0, this material is characterized as negative dielectric anisotropy material. The magnitude of Δε for most of the known negative dielectric anisotropy nematic materials are relatively small, e.g., -0.5 to -2.0. On the other hand, if Δε>0, the material is a positive dielectric anisotropy material and many of the positive dielectric anisotropy materials had high values, e.g., +10 to +20. Theoretically, it has been predicted that materials with positive Δε would give rise to the field induced dielectric realignment; in other words, be useful as display elements in twisted nematic field effect display devices. The threshold voltage dependence on Δε is shown in the following equation: ##EQU1##
k 11 , k 22 , k 33 are materials elastic constants
V c = threshold voltage
Thus, in order to have the threshold voltage in the commonly accessible range (e.g., 1 to 10V rms), (the required cell thickness would be in the 6 to 25 micron thick range), the value of Δε must be at least in the range of 10 to 1, provided that all the other physical constants do not vary considerably. Thus, it is conveivable to make mixtures between "strongly" positive and "weakly" negative dielectric anisotropy materials. Since the magnitude of Δε of the solute (positive dielectric anisotropy) is far greater than that of the solvents (negative dielectric anisotropy), less solute material (2 to 35%) can be utilized in order to obtain acceptable averaged Δε value which is yet within the desirable range. By proper choice of solute and solvent combination, many positive dielectric anisotropy nematic mixtures with desirable nematic temperature range, desired Δε value (or threshold voltage), and low viscosity, which will reduce the ΔV - Vsat - Vth value, can be obtained, according to the principles of this invention.
SOLVENTS
Solvents suitable for use in preparing the nematic liquid crystals of this invention are those materials classed as weakly negative dielectric anisotropy nematic non-Schiff base materials.
The preferred solvents include the following compositions:
1. Compounds selected from the group of compounds having the general formula: ##STR2## in eutectic mixture with corresponding compounds having the general formula: ##STR3## wherein, in each class of compounds R and R' are lower alkyl groups having from 1 to 4 carbon atoms, corresponding compounds being those compounds in which R is the same in both compounds and R' is the same in both compounds.
2. Combinations of two eutectic mixtures as set forth in Paragraph 1 above, R and R' in one such eutectic mixture being different from R and R' in the other of said eutectic mixture in combination.
3. Compounds selected from the group having the general formula: ##STR4## wherein R is lower alkyl group having from 1 to 7 carbon atoms when R' is a lower alkoxy group having from 1 to 7 carbon atoms and wherein R is a lower alkoxy group having from 1 to 7 carbon atoms when R' is a lower alkyl group having from 1 to 7 carbon atoms.
4. Compounds selected from the group having the general formula: ##STR5## wherein R and R' are lower alkyl groups having from 1 to 7 carbon atoms and a and b may both be H- either a or b may be Cl-.
SOLUTES
Solutes suitable for use in preparing the nematic liquid crystals of this invention are those materials classed as strongly positive dielectric anisotropy nematic non-Schiff base materials.
Specific solutes include the following compositions:
1. Compounds selected from the group having the general formula: ##STR6## wherein R is a lower alkyl group or lower alkoxy group having from 1 to 7 carbon atoms and mixtures of two or more compounds selected from said group having differing alkyl or alkoxy chain lengths.
2. Compounds selected from the group having the general formula: ##STR7## wherein R is a lower alkyl group or lower alkoxy group having from 1 to 7 carbon atoms and mixtures of two or more compounds selected from said group having differing alkyl or alkoxy chain lengths.
3. Compounds selected from the group having the general formula: ##STR8## wherein R is a lower alkyl group or lower alkoxy group having from 1 to 7 carbon atoms and mixtures of two or more compounds selected from said group having differing alkyl or alkoxy chain lengths.
SPECIFIC EXAMPLES
The following examples illustrate various specific compositions but do not comprehend the numberless combinations which are within the scope of the invention.
EXAMPLE 1
Very attractive solute compositions are prepared by mixing in the 40:60 percent to 60:40 percent range two members of the class of compounds having the general formula: ##STR9## wherein R is a lower alkyl group having from 1 to 7 carbon atoms Examplary of such compositions are 40:60 and 60:40 mixtures of such compound wherein R = 3 or R = 4 with such compound wherein R = 7. Either of these solute compositions gives an excellent nematic liquid crystal material when dissolved in the 3 percent to 35 percent range in one of the solvents non-Schiff base described herein. Such liquid crystal materials are stable for an indefinite period of time of as yet unknown duration which greatly exceeds the normal effective life of Schiff base liquid crystals.
EXAMPLE 2
Equal amounts of p'-cyanophenyl-p-n-heptylbenzoate and p'-cyanophenyl-p-n-butylbenzoate mixed to form a solute in 20 percent concentration, by weight, in a solvent made up of a eutectic mixture of ##STR10## combined with a eutectic mixture of ##STR11## (E. Merck's Licrystal Nematic Phase 5) resulted in an excellent nematic liquid crystal material which has a long term stability of indefinite duration.
The electro-optical properties of the above mixture is shown below. (3 sq. cm. area, 12.5 micron thick.) All the data were taken at room temperature (25° C.).
__________________________________________________________________________ Capacitance.sup.1Bulk (pf) Vth.sup.2 Vsat.sup.3 Response Times.sup.4Resistivity C.sub.∥ (V rms (milliseconds)(ohms cm.) C.sub.795 60 Hz AC) Delay Rise Decay__________________________________________________________________________3.7 × 10.sup.11 3250/5000 1.6 2.4 60 40 200__________________________________________________________________________ Notes: .sup.1 C.sub.11 indicates the capacitance measured when the device is fully activated; e.g., above its Vsat. C⊥ indicates the capacitance measured below its Vth. .sup.2 Vth: Threshold voltage; voltage at which the photomultiplier reading reaches 5% transmittancy when viewed at normal angle. .sup.3 Vsat: Saturation voltage; voltage at which the photomultiplier reading is 95% from its "steady-state" value. .sup.4 Delay Time: The time span between the signal "on" and the time at which the photomultiplier reaches 5%. Rise Time: The time span between 5% to 95% changes of the photomultiplier readings. Decay Time: The time span between 95% to 5% changes of the photomultiplier readings.
EXAMPLE 3
Suitable nematic, either monotropic or enantio-thermotropic, solvent materials have been chosen from the homologous series of the formula ##STR12## It was found those compounds with A = n--C 7 H 15 , B = --OCH 3 ; A = n--C 3 H 13 --O--, B = --n--C 4 H 9 ; A = n--C 6 H 13 --O--, B = --n--C 5 H 11 ; A = n--C 4 H 9 , B = O-n-C 6 H 13 , were suitable. This series of compounds were reported for the first time, by M. E. Neubert, L. T. Carlino, R. D. 'Sidocky and D. L. Fishel at Kent State University to an NSF Grant No. GH-34164-X.
As another component of the solvent nematic material, one of the following three compounds were used with equally good results: ##STR13## These three compounds have extremely wide nematic temperature ranges and hence used in this system mainly to improve the operational temperature ranges of the display devices. This will obviously also improve the storage temperature ranges of the product. These three compounds were published in Eastman Organic Chemical Bulletin, Vol. 45, No. 1, 1973.
EXAMPLE 5
Non-Schiff base solute materials were added to the solvent compositions of Examples 3 and 4. One such material is the compound ##STR14## in the 3 to 50 percent, and preferrably in the 3 to 20 percent range of concentration. These compositions had good electrooptical characteristics in the desired liquid nematic temperature range.
EXAMPLE 6
One material consisting of 0.2762 part of 4'-n-butylphenyl-4-n-hexyloxybezoate, 0.2762 part of 4'-methoxyphenyl-4-n-heptylbenzoate, 0.2762 part of 4'-pentylphenyl-4-n-hexyloxybenzoate, 0.1382 part of 4'-n-pentylphenyl-3-chloro-4-(4'-n-pentylbenzoyloxy)-benzoate and 0.0332 part of 4'-cyanophenyl-4-n-heptylbenzoate, exhibited suitable electro-optical characteristics to be used in any twisted nematic field effect display devices.
The electrical resistivities of the display cells made of the above formula did not deteriorate substantially over a prolonged period of time, even with organic plastic peripheral sealing display device cells. Under extremely high humidity ambient, the electrical resistivities decreased at much slower rate as compared with those cells made of Schiff base materials, however, the process was reversed as soon as the cells were stored at normal ambient conditions and reversed at a much faster rate in slightly heated dry atmosphere. On the contrary, those devices constructed from Schiff base material, under identical test conditions, never exhibited these resistivly reversal processes.
In general solute concentrations from about 3 percent to about 50 percent were suitable, with the 3 to 35 percent range being most usable and the 3 to 20 percent concentration range giving the best results in terms of both liquid nematic temperature range and electro-optic characteristics.
The foregoing examples illustrate the great advantage of using the compositions of the invention and it will be apparent that within the materials available and the concentration ranges suitable an almost infinite variety of liquid crystal compositions can be formulated by blending solute and/or solvent constituents and varying the concentrations of the individual components in the compositions.
In its broader aspects, the present invention contemplates all compositions which include a solute which comprises a strongly positive dielectric anisotropy nematic liquid crystal material in concentrations of from about 3 percent to about 50 percent, and preferrably in about the 3 to 35 percent concentration range, in a solvent which comprises a weakly negative dielectric anisotropy nematic liquid crystal material which combination has the following properties:
1. The compositions exhibit nematic characteristics in the normal room temperature range and the nematic condition extends above and below that range far enough to encompass normal ambiant conditions for conventional use in display units. Typically this would include temperatures as low as perhaps 15° or 20° C. to as high as perhaps 35° or 40° C., although a somewhat narrower range would be quite satisfactory if the center of the range approximates normal room temperature.
2. The solute must exhibit strongly positive dielectric anisotropy; i.e., the positive dielectric anisotropy of the solute must be strong enough to give the final composition a positive dielectric anisotropy when the solute constitutes less than half of the total composition, and preferrably when the solute constitutes only about 1/50 to 1/3 the total composition, on a molar basis.
3. Within its nematic temperature range, the composition must exhibit electro-optic behavior in conventional display devices, e.g. of the type disclosed in references 8 through 14 when voltages achievable in and compatible with solid state electronic devices. This would generally encompass voltages from a fraction of a volt, e.g., as low as 0.1 volt to as high as 20 volts, although higher voltages could be used. D.C. voltages or A.C. voltages up to 10 kilohertz would conventionally be used.
Without limiting the operating range or the types of devices in which the compositions of this invention may be used, a typical device might be one of those devices described in U.S. Pat. Nos. 3,731,986, or 3,322,485, just to select examples, in which the thickness of the nematic liquid crystal material might be from less than 6 μ to somewhat greater than 25 μ and which might exhibit electro-optic properties under applied threshold voltages of from as low as 0.2 volts to as high as perhaps 7 or 8 volts.
Included within the invention are the specific materials, and their equivalents, and the various combinations and mixtures of these materials which would fall within the scope of the claims as set forth hereinafter.
REFERENCES CITED IN THE SPECIFICATION
The following patents and publications are incorporated herein as background material and no representation is made respecting pertinence or completeness:
1. Brown, G. H., CHEMISTRY, 40, 10 1967.
2. brown, G. H., ANAL. CHEM., 41, 26A 1969
3. brown, G. H., Shaw, W. G., CHEM. REV., 57, 1049, 1957.
4. american chemical society. ordered fluids & liquid crystals. (advances in Chemistry. Ser., No. 63) 1967. 11.50 (ISBN 0-8412-0064-5) Am. Chemical.
5. Brown, G., et al. LIQUID CRYSTALS PROCEEDINGS OF 1965 CONFERENCE, 1967 30.00 Gordon.
6. Gray, G. W., MOLECULAR STRUCTURE & THE PROPERTIES OF LIQUID CRYSTALS. 1962 11.00 (SBN 0-12-296556.6) Acad. Pr.
7. Schuele, Donald E., ed. A REVIEW OF THE STRUCTURE & PHYSICAL PROPERTIES OF LIQUID CRYSTALS. 11.50 Chem. Rubber.
8. U.S. Pat. No. 3,322,485 R. Williams - May 30, 1967
9. U.S. Pat. No. 3,540,796, J. E. Goldmacher et al, Nov. 17, 1970
10. U.S. Pat. No. 3,597,044, J. A. Castellano, Aug. 3, 1971
11. U.S. Pat. No. 3,656,834, I. Haller, et al, April 18, 1972
12. U.S. Pat. No. 3,675,987, M. J. Rafuse, July 11, 1972
13. U.S. Pat. No. 3,703,329, J. A. Castellano, Nov. 21, 1972.
14. U.S. Pat. No. 3,731,986, J. L. Fergason, May 8, 1973. | Nematic liquid crystal materials suitable for use in displays and in other liquid crystal applications comprising particular combinations of positive and negative dielectric anisotropy nematic materials are disclosed. | 2 |
RELATED APPLICATIONS
This is a division of application Ser. No. 09/146,318 filed Sep. 3, 1998, now U.S. Pat. No. 6,187,284, which claims the benefit of U.S. Provisional application Serial No. 60/057,485, filed Sep. 3, 1997.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention concerns methods for radiolabeling proteins and peptides with fluorine-18 (F-18). More particularly, these proteins and peptides are radiolabeled with F-18 by reacting a thiol group contained therein with an F-18-bound labeling reagent which also has a group that is reactive with thiols. The resulting F-18-labeled proteins and peptides are useful in imaging targeted tissue by clinical positron emission tomography.
2. Description of the Related Art
Positron emission tomography (PET) is a high resolution, non-invasive, imaging technique for the visualization of human disease. In PET, 511 keV gamma photons produced during positron annihilation decay are detected. In the clinical setting, fluorine-18 (F-18) is one of the most widely used positron-emitting nuclides. F-18 has a half-life (t½) of 110 minutes, and emits β+particles at an energy of 635 keV. It is 97% abundant.
The short half-life of F-18 has limited or precluded its use with longer-lived specific targeting vectors such as antibodies, antibody fragments, recombinant antibody constructs and longer-lived receptor-targeted peptides. In addition, complicated chemistry has been required to link the inorganic fluoride species to such organic targeting vectors. In typical synthesis methods, an intermediate is radiofluorinated, and the F-18-labeled intermediate is purified for coupling to protein amino groups. See, e.g., Lang et al., Appl. Radiat. Isol ., 45 (12): 1155-63 (1994); Vaidyanathan et al., Bioconj. Chem ., 5: 352-56 (1994).
These methods are tedious to perform and require the efforts of specialized professional chemists. They are not amenable to kit formulations for use in a clinical setting. Multiple purifications of intermediates are commonly required, and the final step, involving linkage to protein lysine residues, usually results in 30-60% yields, necessitating a further purification step prior to patient administration. In addition, these methods result in fluorinated targeting species which accumulate in the kidney, somewhat like radiometals.
It was recently reported that 18 F-fluoroiodomethane ( 18 FCH 2 I) is a useful intermediate for the fluorination of organic intermediates. Zheng et al., J. Nucl. Med ., 38: 177P (Abs. 761) (1997). In this process, diiodomethane is fluorinated with the F-18 ion by a room temperature reaction in acetonitrile solvent, resulting in up to a 40% yield. The 18 FCH 2 I is then distilled into reaction vials containing various strong nucleophiles in anhydrous acetonitrile and allowed to react at 80° C. for fifteen minutes. Nucleophilic attack by carboxylates, thiolates, phenolates, and amines in particular, replaces the remaining iodine of 18 FCH 2 I, with overall yields of 10 to 35%. The reaction products can be purified by reverse-phase HPLC. Fluoromethyl diethylamine, fluoromethyl benzoate, fluoromethyl benzyl thioether and fluoromethyl 4-(2-hydroxy-3-aminopropoxy)-carbazole have been made by this method.
As discussed above, the currently available methods for labelling protein-based targeting vectors with F-18 are unsuitable. There is a need, therefore, for a simple, efficient method for incorporating the F-18 radionuclide into peptide-containing targeting vectors, such as proteins, antibodies, antibody fragments, and receptor-targeted peptides, to allow the use of such targeting vectors in routine clinical positron emission tomography.
SUMMARY OF THE INVENTION
The present invention provides methods for incorporating the F-18 radionuclide into peptide-containing targeting vectors.
In accordance with one embodiment of the invention there is provided a method for radiolabeling thiol-containing peptides with fluorine-18 (F-18), comprising reacting a peptide comprising a free thiol group with a labelling reagent having the general formula 18 F—(CH 2 ) m —CR 1 R 2 —(CH 2 ) n —X, wherein:
n is 0, 1 or 2;
m is 0, 1 or 2;
and n+m is 0, 1, or 2;
X is selected from the group consisting of iodide, bromide, chloride, azide, tosylate, mesylate, nosylate, triflate, unsubstituted maleimide, maleimide substituted with one or two alkyl groups, and maleimide substituted with a sulfonate group; and
R 1 and R 2 are the same or different and are selected from the group consisting of iodide, bromide, chloride, azide, tosylate, mesylate, nosylate, triflate, hydrogen, —CONH 2 , carboxyl, hydroxyl, sulfonic acid, tertiary amine, quaternary ammoniumun, unsubstituted alkyl, substituted alkyl, —COOR′, —CONR′ 2 , or COR′, wherein the substituents of the substituted alkyl groups are selected from the group consisting of —CONH 2 , carboxyl, hydroxyl, sulfonic acid, tertiary amine and quaternary ammonium and wherein R′ is a C 1 -C 6 alkyl or phenyl.
In accordance with another embodiment, there is provided a method for radiolabeling thiol-containing peptides with F-18, comprising reacting a peptide comprising a free thiol group with a F-18 fluorinated alkene, wherein at least one of the two double-bonded carbon atoms bears at least one leaving group selected from the group consisting of iodide, bromide, chloride, azide, tosylate, mesylate, nosylate and triflate.
In accordance with another embodiment of the invention, a peptide that has been radiolabeled with F-18 as described above is delivered to a targeted tissue using a bispecific antibody (bsMAb) or a bispecific antibody fragment (bsFab) containing at least one arm that is specific to the targeted tissue and at least one other arm that is specific to the F-18-labeled peptide or a low molecular weight hapten conjugated to the F-18-labeled peptide.
In this methodology, the bsMAb or the bsFab is administered to a patient and allowed to localize to the targeted tissue. Some time later (after the unbound bsMAb or the unbound bsFab is allowed to clear), the F-18-labeled peptide or the hapten conjugate thereof is administered to the patient. Since at least one of the arms of the bsMAb or the bsFab is specific to the F-18-labeled peptide or the hapten conjugated to the F-18-labeled peptide, the F-18-labeled peptide is also localized to the target. After the unbound F-18-labeled peptide or the unbound hapten conjugate thereof is allowed to clear, the target is then visualized by routine clinical positron emission tomography.
The bsMAb or bsFab is ideally monoclonal and humanized. Preferably, the F-18-labeled peptide contains a thiol group. Examples of suitable peptides are X-Gly-D-Tyr-D-Trp-Gly-D-Lys(X)-Gly-D-Tyr-D-Trp-OH wherein X represents a free or protected amino acid group, Ac-Cys(Y)-D-Tyr-D-Trp-Gly-D—Cys(Y)-Gly-D-Tyr-D-Trp-OH wherein Y represents a free or protected thiol group, and Ac-Gly-D-iodo-Tyr-D-Trp-Gly-D-Lys(Ac)-Gly-D-iodo-Tyr-D-Trp-OH. The hapten can be a metal chelate complex comprising, for example, manganese, iron, or gadolinium which are useful in magnetic resonance imaging (MRI).
The bsMAb, bsFab, and associated methodologies described above are disclosed in U.S. Provisional Application Serial No. 60/090,142 (entitled “Production and use of novel peptide-based agents for use with bispecific antibodies” and filed Jun. 22, 1998), the entire contents of which are herein incorporated by reference.
These and other objects and aspects of the invention will become apparent to the skilled artisan in view of the teachings contained herein.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides simple and efficient methods for incorporating the F-18 radionuclide into peptide-containing targeting vectors, such as proteins, antibodies, antibody fragments and receptor-targeted peptides. For convenience, the term “peptide” is used below and in the claims to refer to proteins, antibodies, antibody fragments and receptor-targeted peptides. The methods of the present invention makes such targeting vectors available for routine clinical positron emission tomography.
Of all nucleophiles present on peptides, only the free thiol group can be rapidly alkylated at neutral pH and moderate temperature. The present invention takes advantage of this unique property of free thiol groups, and provides methods for labelling thiol-containing peptides with F-18.
In accordance with one embodiment, the method of the present invention comprises the following reaction:
wherein n is 0, 1 or 2, m is 0, 1 or 2, and n+m is 0, 1, or 2, and X is a substitutable leaving group such as iodide, bromide, chloride, azide, tosylate, mesylate, nosylate, triflate and the like. Alternatively, X is maleimide or a substituted maleimide, substituted, for example with one or two alkyl groups or a sulfonate group. Examples of suitable substituted maleimides include 3-methylmaleimide, 3,4-dimethylmaleimide and 3-sulfo-maleimide. R 1 and R 2 can be the same or different and, as discussed in more detail below, are chosen for the desirable physical properties they bring to the reagent. In general, R 1 and R 2 can be selected from the same groups as X, and can be the same as or different from X. Alternatively, R 1 and R 2 each independently can be hydrogen, a substituted or unsubstituted linear or branched alkyl group, or a carbonyl function such as an ester, amide or ketone, for example, —COOR′, —CONR′ 2 , or COR′, where R′ is a C 1 -C 6 alkyl or phenyl. Examples of suitable R 1 and R 2 groups or substituents thereon also include groups which impart aqueous solubility, such as —CONH 2 , carboxyl, hydroxyl, sulfonic acid and tertiary amine or quaternary ammonium.
In accordance with another embodiment of the invention, the peptide is labeled with an F-18 fluorinated alkene, wherein at least one of the two double-bonded carbon atoms bears at least one leaving group selected from the group consisting of iodide, bromide, chloride, azide, tosylate, mesylate, nosylate and triflate. Examples of suitable fluorinated alkenes include 18 F—CH═CI 2 , 18 F—CI═CH 2 , or 18 F—CI═CI 2 . The labeling reaction is analogous to the one described above.
The methods of present invention can be used to label any thiol-containing peptide. Of particular interest are peptides useful as targeting vectors. Examples of such targeting vectors include antibodies, F(ab′) 2 , F(ab) 2 , Fab′ and Fab fragments, single-chain sub-fragments such as sFvs, divalent constructs such as dsFvs, and polypeptides containing one or more free thiol groups. See Choi et al., Cancer Res ., 55: 5323-29 (1995). Further examples include antibody constructs such as antibodies comprising IgG 3 or IgG 3 -F(ab′) 2 frameworks. IgG 3 's have multiple hinge-region disulfide groups which can be reduced to generate multiple free thiol groups.
Peptides that originally do not comprise a free thiol group can be labelled in accordance with the present invention by first modifying the peptide to add a free thiol group by methods known to those skilled in the art. For example, the peptide can be thiolated with reagents such as 2-iminothiolane, or intrinsic disulfide bonds such as cystine residues can be reduced. A combination of both modifications also can be performed, such as the acylation of lysine residues with N-succinimidyl-3-(2-pyridylthio)-propionate (SPDP) followed by the controlled reduction of the appended disulfide bond.
In one embodiment of the present invention, the peptide is a Fab or Fab′ fragment. These peptides have free thiol groups in their hinge-region, a site which is both specific and remote from the antigen-targeting sites.
To optimize the reaction with the thiol-containing peptides, the labelling reagent preferably has the following physical and chemical properties:
(1) The reagent is readily and rapidly synthesized from F-18.
(2) The reagent has adequate aqueous solubility in the neutral (4-8) pH range. By “adequate aqueous solubility” is meant that the reagent readily dissolves at up to a concentration comparable to a stoichiometric amount of the thiol-containing peptide used. If, for example, an antibody is being labeled, a typical antibody concentration is about 50 mg/mL, which corresponds to a molar concentration of about 3×10 −4 M. In this example, the reagent should be soluble at a concentration of about 3×10 −4 M. With lower molecular weight peptide species, more peptide will dissolve without precipitation, and more reagent can be used. Because F-18 is carrier-free, lower concentrations of fluorination agents also might be effective.
(3) The active halides of the reagent are not immediately hydrolyzed by water at neutral pH (pH 4-8). Thus, the halides should react more readily with SH or S − than with H 2 O. As long as the reagent is not immediately hydrolyzed by water (or by neutral buffer solutions), the selectivity and reactivity of the thiol group ensures an efficient peptide labeling reaction.
(4) The leaving group X can be displaced rapidly, specifically, and near-quantitatively by free thiol moieties. A carbo-cationic center can be developed at the carbon atom which is attacked by the nucleophile, for example, R 1 and R 2 can be electron-withdrawing groups. The presence of electron-withdrawing groups alpha to the —C—X functional group also facilitates fast displacement of the X moiety. Examples of useful electron-withdrawing groups include —COR′, —CONR′, —CO 2 R′, —COOH, —CONH 2 , and —SO 3 H, where R′ is a C 1 -C 6 alkyl or phenyl.
In addition, the presence of more than one leaving group in the labelling reagent can be advantageous. Multiple leaving groups, such as iodo groups, attached to the same carbon atom produce steric strain. When a reaction comprises the departure of a single leaving group, this steric strain is relieved, imparting faster reaction kinetics to the thiol displacement of the X group. Thus, in accordance with one embodiment of the invention, the labeling reagent comprises at least two leaving groups, such as two iodo groups.
In accordance with one embodiment of the present invention, the peptide is labeled with a labelling reagent of the general formula 18 F—(CH 2 ) m —CR 1 R 2 —(CH 2 ) n —X, wherein n is 0, 1 or 2, m is 0, 1 or 2, and n+m is 0, 1, or 2, and X is a substitutable leaving group such as iodide, bromide, chloride, azide, tosylate, mesylate, nosylate, triflate, and the like. Alternatively, X is maleimide or a substituted maleimide, substituted, for example with one or two alkyl groups. Examples of suitable substituted maleimides include 3-methylmaleimide, 3,4dimethylmaleimide and 3-sulfo-maleimide. R 1 and R 2 can be the same or different and, as discussed above, are chosen for the desirable physical properties they bring to the reagent. In general, R 1 and R 2 can be selected from the same groups as X, and can be the same as or different from X. Alternatively, R 1 and R 2 each independently can be hydrogen, a substituted or unsubstituted linear or branched alkyl group, or a carbonyl function such as an ester, amide or ketone, for example, —COOR′, —CONR′ 2 , or COR′, where R′ is a C 1 -C 6 alkyl or phenyl. Examples of suitable R 1 and R 2 groups or substituents thereon also include those which impart aqueous solubility, such as —CONH 2 , carboxyl, hydroxyl, sulfonic acid and tertiary amine or quaternary ammonium.
Examples of suitable labelling reagents include 18 F—CI 3 ; 18 F—CHI 2 ; 18 F—CI 2 COOH; 18 F—CI 2 COOCH 3 ; 18 F—CI 2 CH 2 OH; 18 F—CHICH 2 OH; 18 F—CHICOOCH 3 ; 18 F—CI 2 CH 2 COOH; 18 F—CI 2 CH 2 N + (CH 3 ) 3 ; 18 F—CI 2 CH 2 -maleimide; 18 F—CI 2 —CONH 2 ; 18 F—CI 2 —CO 2 CH 3 ; 18 F—CHBr 2 ; 18 F—CBr 2 CH 2 CH 2 —SO 3 H; 18 F—CH 2 CI 2 COOH; 18 F—CH 2 CI 2 CONH 2 ; 18 F—CHICO 2 CH 3 ; 18 F—CI 2 CONH 2 ; 18 F—CHICONH 2 ; 18 F—CBr 2 CH 20 H; CF 3 COCI 2 — 18 F; CH 3 COCBr 2 — 18 F; 18 F—CHBrCN; 18 F—CI 2 CHCN; CBrF 2 — 18 F; 18 F—CBr(CONH 2 ) 2 , and C 6 H 5 —COCBr 2 — 18 F. Other suitable labeling reagents will be apparent to those skilled in the art.
The labeling reagent can be made by the F-18 fluorination of a corresponding compound. The following are examples of compounds which can be fluorinated to make the labeling reagents set forth above: CI 4 ; CHI 3 ; CHI 2 COOCH 3 ; CI 3 COOH; CI 3 COOCH 3 ; CI 3 CH 2 OH; CHI 2 CH 2 OH; CI 3 CH 2 COOH; CI 3 CH 2 N + (CH 3 ) 3 ; CI 3 CH 2 -maleimide; CI 3 —CONH 2 ; CI 3 —CO 2 CH 3 ; CHIBr 2 ; CIBr 2 CH 2 CH 2 —SO 3 H; CH 2 CI 3 COOH; CH 2 CI 3 CONH 2 ; CHI 2 CO 2 CH 3 ; CI 3 CONH 2 ; CHI 2 CONH 2 ; CBr 3 CH 2 OH; CF 3 COCI 3 ; CH 3 COCBr 3 ; Br 2 CHCN; CI 3 CHCN; CBr 2 F 2 ; CBr 2 (CONH 2 ) 2 and C 6 H 5 —COCBr 3 . Other suitable compounds will be apparent to those skilled in the art.
In accordance with another embodiment of the invention, the labeling reagent is an F-18 fluorinated alkene, wherein at least one of the two double-bonded carbon atoms bears at least one leaving group selected from the group consisting of iodide, bromide, chloride, azide, tosylate, mesylate, nosylate and triflate. Examples of suitable fluorinated alkenes include 18 F—CH═CI 2 , 18 F—CI═CH 2 , and 18 F—CI═CI 2 . These labeling reagents can be made by the F-18 fluorination of corresponding compounds, such as ICH═CI 2 ; CI 2 ═CH 2 ; CI 2 ═CI 2 . Other fluorinated alkenes useful in accordance with the present invention will be apparent to those skilled in the art.
F-18 can be obtained from cyclotrons after bombardment of O-18-enriched water with protons. The enriched water containing H— 18 F can be neutralized with a base having a counter-ion that is any alkali metal (M), such as potassium or another monovalent ion, and the water can be evaporated off to give a residue of M— 18 F, which can be taken up in an organic solvent for further use. In general, the counter-ion is selected to enable the fluoride ion to react rapidly in an organic phase with a halogen. Potassium is generally used as a counter-ion because it is cheaper than cesium. However, with carrier-free F-18, trivial amounts of counter-ion are required, and counter-ion cost largely can be ignored.
Although potassium is useful as a counter-ion in accordance with the present invention, cesium is preferred to potassium because cesium is a larger ion with a more diffuse charge. Accordingly, cesium has looser ionic interactions with the small fluoride atom, and therefore does not interfere with the nucleophilic properties of the fluoride ion. For similar reasons, potassium is preferred to sodium, and, in general, the suitability of a Ia metal as a counter-ion in accordance with the present invention increases as you go down the periodic table. Group Ib reagents, such as silver, also are useful as counter-ions in accordance with the present invention. Further, organic phase transfer-type ions, such as tetraalkylammonium salts, also can be used as counter-ions.
Because fluoride is the most electronegative element, it has a tendency to become hydrated and lose its nucleophilic character. To minimize this, the labeling reaction is preferably performed under anhydrous conditions. For example, fluoride (as potassium fluoride or as a complex with any of the other counter-ions discussed above) can be placed in organic solvents, such as acetonitrile or THF. With the help of agents which bind to the counter-ion, such as Kryptofix 2.2.2 (4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8.8.8]-hexacosane), the fluoride ion is very nucleophilic in these solvents.
As discussed above, the labeling reagent is used to label targeting vectors comprising a thiol-containing peptide with F-18 according to the following reaction:
Alternatively, the labeling reagent is a F-18 fluorinated alkene, wherein at least one of the two double-bonded carbon atoms bears at least one leaving group selected from the group consisting of iodide, bromide, chloride, azide, tosylate, mesylate, nosylate and triflate. This F-18 fluorinated alkene labels targeting vectors in an analogous manner to the reaction set forth above.
Directing the reaction of the fluorinated labeling reagent towards free thiol groups on the targeting vector allows near-quantitative incorporation of F-18 into the targeting vector within a short time period. Generally, the reaction will be completed within a few minutes at room temperature, and complicated purification steps will not be necessary. Given the very short half-life of F-18, the speed of the reaction is very important. Moreover, because free F-18 exchanges readily with hydroxyl ions in hydroxyapatite crystals in bone, and, therefore, is a bone-seeking agent, the reduced amount of free fluoride remaining in the final product also is an important advantage of the present invention.
The embodiments of the invention are further illustrated through examples which show aspects of the invention in detail. These examples illustrate specific elements of the invention and are not to be construed as limiting the scope thereof.
EXAMPLES
Fluorodiiodoacetic acid ( 18 F—CI 2 COOH)
100 mCi of F-18 fluoride (obtained from bombardment of O-18-enriched water) in dry tetrahydrofuran containing Kryptofix 2.2.2 (4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane) and a slurry of potassium carbonate is treated with triiodoacetic acid. After a 30 minute reaction at room temperature, the desired labelling reagent, 18 F—CI 2 COOH, is obtained and purified by reverse-phase column chromatography. This labelling reagent is then used to label a variety of thiol-containing targeting vectors, or is shipped to clinical sites for the same usage.
F-18-Labeled Fab′-SH Fragment
A 1 mg vial of lyophilized Fab′-SH-NP4 (an anti-carcinoembryonic antigen antibody fragment) is reconstituted with 1 mL of a solution of 18 F—CI 2 COOH in 0.1 M sodium acetate buffer at pH 6. The reaction is allowed to proceed for 30 minutes at room temperature.
An aliquot of the mixture is removed for analysis by HPLC using a size-exclusion sizing column and by ITLC (instant thin-layer chromatography) using silica gel-impregnated glass-fiber strips (Gelman Sciences). This analysis reveals that the antibody fragment's hinge-region thiol groups effect nucleophilic displacement of both iodine atoms of 18 F—CI 2 COOH, and that this reaction proceeds in near-quantitative yield. The F-18-labeled Fab′ fragment is therefore ready for injection.
Fluorodiiodomethane ( 18 F—CHI 2 )
A sample of 100 mCi of F-18 fluoride (obtained from bombardment of 0-18-enriched water) in dry acetonitrile containing Kryptofix 222 and a slurry of potassium carbonate is treated with triiodomethane. After a 30 minute reaction at room temperature the labelling reagent 18 F—CHI 2 is obtained and purified by reverse-phase column chromatography. The labelling reagent is then used to label a variety of thiol-containing targeting vectors, or is shipped to clinical sites for the same usage.
F-18-Labeled Octreotide
A 1 mg vial of lyophilized, reduced octreotide (D-Phe-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-ol) is reconstituted with 1 mL of a solution of 18 F—CHI 2 (made up first in DMSO) in 0.1 M sodium acetate buffer at pH 6, containing 20% DMSO. The reaction is allowed to proceed for 30 minutes at room temperature. Alternatively, can be effected at elevated temperatures, and in non-aqueous solvents, e.g., DMSO, and later cooled and/or diluted for injection.
An aliquot of the labeling mixture is removed for analysis by HPLC using a size-exclusion sizing column and ITLC (instant thin-layer chromatography) using silica gel-impregnated glass-fiber strips (Gelman Sciences). This analysis reveals that the two cysteinyl thiol groups of octreotide effect the nucleophilic displacement of both iodo atoms of 18 F—CHI 2 , and that this reaction proceeds in near-quantitative yield. The F-18-labeled, recyclized (linkage: —S—CH— 18 F—S—) octreotide peptide is therefore ready for injection.
Fluorodiiodoacetamide ( 18 F—CI 2 CONH 2 )
100 mCi of F-18 fluoride (obtained from bombardment of O-18-enriched water) in dry tetrahydrofuran containing Kryptofix 2.2.2 (4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane) and a slurry of potassium carbonate is treated with triiodoacetamide. After a 30 minute reaction at room temperature, the desired labelling reagent, 18 F—CI 2 CONH 2 , is obtained and purified by reverse-phase column chromatography. This labelling reagent is then used to label a variety of thiol-containing targeting vectors, or is shipped to clinical sites for the same usage.
F-18-Labeled Cys-LHRH
A 1 mg vial of lyophilized Cys-LHRH (LHRH whose amine terminus bears an appended cysteine, in reduced, thiol, form) reconstituted with 1 mL of a solution of 18 F—CHICONH 2 in 0.1 M sodium acetate buffer at pH 6. The reaction is allowed to proceed for 2 hours at 50° C. The antibody modified peptide's thiol group effects nucleophilic displacement of the iodo atom of 18 F—CIHCONH 2 , and the reaction proceeds in near-quantitative yield. The F-18-labeled peptide is ready for injection.
It will be apparent to those skilled in the art that various modifications and variations can be made to this invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the claims and their equivalents. | Thiol-containing peptides can be radiolabeled with fluorine-18 (F-18) by reacting a peptide comprising a free thiol group with an F-18-bound labelling reagent which also has a group that is reactive with thiols. The resulting F-18-labeled peptides may be targeted to a tissue of interest using bispecific antibodies or bispecific antibody fragments having one arm specific for the F-18-labeled peptide or a low molecular weight hapten conjugated to the F-18-labeled peptide, and another arm specific to the targeted tissue. The targeted tissue is subsequently visualized by clinical positron emission tomography. | 0 |
TECHNICAL FIELD
This invention relates to sealing gaskets and, more particularly, to gaskets for sealing one end of filter tube assemblies within a pressure vessel assembly.
BACKGROUND ART
Many applications exist where an interface separates two fluids having different properties. It is often necessary to provide a seal at the interface to prevent mixing of the fluids or the transfer of one fluid into a volume occupied by a second fluid. Typically, seals may take the form of compression seals at abutting surfaces, wipers at sliding surfaces and gland-type seals for concentric surfaces.
Compression seals between abutting surfaces are frequently used where the abutting surfaces must be assembled and disassembled. However, the abutting surfaces compressing the seal generally have manufacturing tolerances which effect the parallelism between the surfaces. Further, the structures forming the abutting surfaces may not always be axially aligned so that, again, the surfaces are not parallel. Frequently, both of these conditions exist, requiring that the compression seal accommodate a range of displacements between the abutting surfaces.
Typically, a pressure differential exists across the interface and the seal must exert sufficient sealing force to overcome the forcing effect of the differential pressure. The sealing force is a function of the elasticity of the sealing material, the seal dimensions and the actual displacement to be occupied by the seal. No sealing exists where the displacement is greater than the seal dimensions can occupy. On the other hand, seal removal and installation will be increasingly difficult as seal compression requirements increase.
Thus, it would be desirable for a seal or gasket to retain sealing capability over a wide range of adjoining surface displacements while permitting the surfaces to be assembled or disassembled with a minimum effort. These, and other problems in the prior art, are overcome by the present invention wherein an improved gasket provides a compression seal including both a wiper seal configuration and an axial compression seal configuration.
SUMMARY OF THE INVENTION
A gasket is provided for sealing between an inlet tube and a nested support tube having a seat ring. The gasket has a first surface for axially sealing against the seat ring. A lip member is provided parallel with the first surface for laterally sealing against the support tube. The two sealing actions are, thus, independent from one another while provided by a single gasket member.
In one embodiment, an "O" ring portion defining a circumferential axial slot is provided for fixing to the end portion of the inlet tube. An "L" seal ring portion is then provided for fixing within the axial slot to form both the first sealing surface and the lip member.
A filter tube assembly is provided for mating and sealing with a nested support tube having a depending sealing ring surface formed thereabout. A conventional filter tube having a front and a rear end is provided. A cap may be provided for the front end which seals with the front end and serves to support the front end within a flow vessel. An urging means, such as a spring, may then be provided for bearing against the cap and biasing the rear end of the filter tube toward the support tube sealing ring surface. The rear end of the filter tube includes a gasket having a first portion molded directly to the filter tube rear end and a second portion which has a first sealing surface in facing relationship with the sealing ring surface. The second portion terminates in an extending lip which can sealingly engage the nested support tube.
It is an object of the present invention to maintain a seal in the area adjoining the filter tube and the support tube.
It is another feature of the present invention to enable the filter tube assembly to be removed and replaced on the nested support tube without the need for substantial force to obtain a sealing relationship.
One other feature is to enable the gasket assembly to be conventionally molded with the filter tube assembly.
These and other features and advantages of the present invention will become apparent from the following detailed description, wherein reference is made to the figures in the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a simplified cross sectional view of a filter tube assembly installed on a support tube in accordance with one embodiment of the present invention.
FIG. 2 is a cross-sectional representation of a gasket according to one embodiment of the present invention.
DETAILED DESCRIPTION
Referring now to FIG. 1, there may be seen in partial cross section a filter tube assembly having a sealing gasket in accordance with one embodiment of the present invention. While many applications exist for the gasket herein described, the filter tube assembly depicted in FIG. 1 is a preferred application. The gasket design is particularly suitable for the pressure differentials which exist across a filter element tending to promote fluid interchange at nonsealed interfaces and for ease of assembly at areas which are difficult to access.
The filter tube assembly of FIG. 1 includes filter tube element 10, conventionally formed to separate portions of a fluid external to filter tube 10 from fluid passing to the interior of filter tube 10. The removed material may be solids in a gas or in a liquid, liquid in a gas or the like. Filter tube 10 may have an open front end and an open rear end.
The front end may be sealingly closed by a cap 22. A preferred cap with support assembly is described in U.S. Pat. No. 4,407,664 to Sillers, which disclosure is incorporated herein by reference. Cap 22 may engage in and be supported by support bracket 24 with urging means 26 therebetween for engaging cap 22, similar to the structure depicted in the Sillers' patent.
The rear end of filter tube 10 generally engages an assembly for exiting the material entering the interior of filter tube 10. As shown in FIG. 1, pipe 12 provides support for the filter tube and functions as an outlet pipe for the interior fluid. A sealing surface is generally provided adjacent pipe 12. The sealing surface may be seat ring 14, depicted herein and circumferentially depending from pipe 12, or may be a portion of a bulkhead assembly supporting a plurality of pipes 12. In any event, the sealing surface is generally perpendicular to the axis of pipe 12 and filter tube 10.
As may be seen from FIG. 1, a variety of conditions may exist which affect the ability of any gasket to seal the rear end of filter tube 10 with seat ring 14, or an equivalent bulkhead, and adjacent pipe 12. Seat ring 14, or a corresponding bulkhead, is subject to manufacturing tolerances and to distortions resulting from various thermal and stress gradients. Likewise, the axial alignment between pipe 12 and the support of cap 22 may vary as a result of manufacturing tolerances, installation technique and operating shifts. These conditions, either singly or in combination, tend to provide a variety of interface conditions at the rear end of filter tube 10 which a gasket must accommodate.
Again referring to FIG. 1, a gasket according to the present invention is provided which accommodates the various sealing gap configurations which can arise as a result of manufacturing and operational mismatch conditions. Gasket 16 is placed at the rear end of filter tube 10 and may be fixed thereto to preclude ingestion by the system at various operating pressures. Gasket 16 provides a first sealing surface 18 responsive to axial movement of filter tube 10, compressing a portion of gasket 16 against axial sealing surface 18.
A backup seal, however, is now provided by an extending lip portion 20 forming a lateral sealing surface for engaging the outer diameter of pipe 12. Thus, a first seal is provided responsive to axial conditions and a second seal is provided responsive to lateral conditions. In a preferred embodiment, each seal surface is effective to permit only a maximum effective leakage flow at expected operating and manufacturing mismatch conditions.
As shown in FIG. 1, a single gasket 16 may be provided having two arms in substantially perpendicular relationship. For manufacturing purposes, it may be desirable to form gasket 16 from two distinct pieces, as depicted in FIG. 2. Thus, an "O" ring portion 34 may be provided for fixing to filter tube 10 (FIG. 1). "O" ring 34 may be glued or molded to filter tube 10. A conventional "O" ring is typically used to form the seal herein discussed, responsive only to axial compression to maintain the seal. However, the "O" ring may be bonded to filter tube 10 using conventional manufacturing techniques and a standard autoclave since "O" ring 34 is concentric with filter tube 10.
Thus, where "O" ring 34 is provided for assembly with conventional techniques, circumferential axial slot 38 is formed. Slot 38 functions in cooperation with a "L"-shaped lateral seal ring 36 to form the gasket assembly. A first arm 39 is provided for engaging receiving slot 38. First arm 39 may be suitably fixed within slot 38 by friction and compression forces in some applications or an adhesive or other means may be required to suitably join first arm 39 within slot 38.
Second arm 44 is now provided to obtain the sealing functions. Axial sealing surface 40 is provided for compression engagement with seat ring 14 (FIG. 1), or an equivalent bulkhead. Second arm 44 terminates in lateral sealing surface 42 for sealing against pipe 12 (FIG. 1).
Generally, "O" ring portion 34 and "L" seal ring 36 portion may be formed of the same resilient material. However, it will be appreciated that "O" ring portion 34 may be selected for bonding with filter element 10 and "L" seal ring 36 may be selected for sealing properties. The performance characteristics of a gasket as depicted in FIG. 2 and having an inner diameter "A" for the lateral sealing surface 42 is shown in Table A, below. The filter tube assembly was installed on a support pipe 12 (FIG. 1) having a nominal outside diameter of 4 3/16". Typical dimensions of the gasket components depicted in FIG. 2 are the following:
______________________________________DESCRIPTION FRACTIONS______________________________________"O" ring inner diameter 41/2""O" ring 34 outer diameter 51/8"second arm 44 thickness 1/16"______________________________________
The Durometer reading is a measure of the resilience of the material according to ASTM Standard No. D2240-75. The higher the Durometer value the harder or stiffer the material. Table A is based solely on the performance of lateral sealing surface 42 at a variety of differential pressure conditions. The leakage flow through the seal is indicated and the maximum differential pressure which the seal withstood without opening is illustrated. The chart further indicates the relative difficulty of installing the seal over a standpipe.
TABLE A______________________________________ Seal Leakage Break Instal- (SCFH) Seal @ 7.4 psiDIA. A. Duro- lation 0.5 0.25 Break [max.(in.) meter Difficulty psi psi @ 0.5/0.25 W p psi]______________________________________4 1/16 U-40 No 15.5 20 No [2.5]4 1/16 U-60 No 13 17 No [4.4]4 1/16 U-80 No 16 20 No No4 U-40 No 23 33 No [2.5]4 U-60 No 26.5 36 No [4.9]4 U-80 Some 20 31 No No3 15/16 U-40 No 10 12 No [6.4]3 15/16 U-60 Some 8 9 Yes @ 0.5 [4.9]3 15/16 U-80 Some 10.5 13 No [4.7]______________________________________
As shown in Table A, a variety of acceptable conditions exist with particular reference to the performance parameters of installation difficulty and the seal integrity up to 0.5 psi differential pressure. A preferred configuration for use with a pipe having a nominal 4 3/16" outer diameter includes a lateral seal inner diameter of 4 1/16" with a material having a Durometer reading of 80. This configuration produced an acceptably low leakage rate and ease of installation.
Typically, elastomeric materials are used to form the gaskets depicted in FIGS. 1 and 2. A preferred material is a nitrile rubber and, more particularly, Buna-N, an acrylonitrile-butadienne copolymer. Suitable alternate materials include fluorinated elastomers, such as sold under the trademark VITON, and silicon elastomers.
It is therefore apparent that the present invention is one well adapted to attain all of the objects and advantages hereinabove set forth together with other advantages which will become obvious and inherent from a description of the apparatus itself. It will be understood that certain combinations and subcombinations are of utility and may be obtained without reference to other features and subcombinations. This is contemplated by and is within the scope of the present invention.
As many possible embodiments may be made of this invention without departing from the spirit or scope thereof, it is to be understood that all matters herein set forth in the accompanying drawings are to be interpreted as illustrative and not in any limiting sense. | A gasket (16) for sealing between a filter (10) and a support tube (12) adjacent a seat ring (14). A first sealing surface (18) is provided on the gasket (16) for sealing axially against the seat ring (14). A second sealing surface (20) on the same gasket (16) for lateral sealing against the support tube (12) to maintain a sealed condition when axial sealing cannot be sustained. | 5 |
The application claims the benefit of U.S. Provisional Application No. 60/297,482, filed Jun. 13, 2001, and claims the right to priority based on French Patent Application No. 0106330, filed May 14, 2001, and the contents of both applications are incorporated herein by reference.
BACKGROUND OF THE INVENTION
The present invention relates to novel compounds which make it possible to transfer nucleic acids into cells. More precisely, these novel compounds are lipid derivatives of polythiourea. They are useful for the in vitro, ex vivo or in vivo transfection of nucleic acids into various cell types.
With the development of biotechnology, the possibility of effectively transferring nucleic acids into cells has become a necessity. It may involve the transfer of nucleic acids into cells in vitro, for example, for the production of recombinant proteins, or in the laboratory for studying the regulation of the expression of genes, the cloning of genes, or any other manipulation involving DNA. It may also involve the transfer of nucleic acids into cells in vivo, for example for the creation of transgenic animals, the production of vaccines, labeling studies or also therapeutic approaches. It may also involve the transfer of nucleic acids into cells ex vivo, in approaches including bone marrow transplants, immunotherapy or other methods involving the transfer of genes into cells collected from an organism for the purpose of their subsequent readministration.
Several methods have been proposed for the intracellular delivery of exogenous genetic material. One of them, in particular, is based on the use of nonviral vectors which constitute a highly advantageous alternative to the viral methods which are not completely risk free. These synthetic vectors have two main functions: to complex and to compact the nucleic acid to be transfected, and to promote its passage across the plasma membrane and possibly across the nuclear envelope.
Several families of synthetic vectors have thus been developed, such as for example polymers or alternatively biochemical vectors (consisting of a cationic protein combined with a cellular receptor ligand), but a major advance has in particular been made with the development of lipofectants and more particularly of cationic lipids. It has thus been demonstrated that cationic lipids, because of their overall positive charge, spontaneously interfere with DNA which is globally negative, forming nucleolipid complexes capable both of protecting the DNA against nucleases and of binding to the cellular membranes for intracellular release of the DNA.
Various types of cationic lipids have been synthesized to date: lipids comprising a quaternal ammonium group (for example DOTMA, DOTAP, DMRIE, DLRIE, and the like), lipopolyamines such as for example DOGS, DC-Chol or alternatively the lipopolyamines disclosed in Patent Application WO 97/18185, lipids combining both a quaternary ammonium group and a polyamine such as DOSPA, or alternatively lipids comprising various other cationic entities, in particular amidinium groups (for example ADPDE, ADODE or the lipids of patent application WO 97/31935).
However, the use of these cationic lipids as transfection agent still poses numerous problems, and their efficiency remains to be improved. In particular, it has been observed that to obtain efficient and stable nucleolipid complexes, it is in general necessary for these complexes to be highly cationic. However, it would be desirable to be able to have available vectors which are not cationic so as to form, with the nucleic acid, particles which are globally neutral or negative. Indeed, it has been observed that the globally cationic complexes formed between the nucleic acid and the cationic lipids tend to be captured by the reticuloendothelial system, which induces their elimination. In addition, the plasma proteins tend to become adsorbed at their surface because of the overall positive charge of the complexes formed, and this results in a loss of the transfection power. Furthermore, in a context of local injection, the presence of a large overall positive charge prevents the diffusion of the nucleic acid complexes away from the site of administration because the complexes become adsorbed onto the extracellular matrices; the complexes can therefore no longer reach the target cells, which consequently causes, a decrease in the transfer efficiency in relation to the injected quantity of complexes. Finally, it has also been observed, in many instances, that cationic lipids have an inflammatory effect.
BRIEF SUMMARY OF THE INVENTION
The object of the present invention is precisely to provide novel transfecting compounds which are innovative by virtue of their polythiourea functional group and which are capable of being efficiently used for the in vitro, ex vivo or in vivo transfection of nucleic acids. These novel compounds are particularly advantageous because:
the absence of positive charges from their structure makes it possible to solve the many problems raised by the use of cationic vectors discussed above,
just like cationic lipids, they are capable of complexing and compacting nucleic acids and of promoting their transfection.
A first subject of the present invention is thus transfecting compounds characterized in that they consist of a polythiourea part linked to a lipid via a spacer.
In particular, the subject of the present invention is transfecting compounds of general formula (I):
in which:
l is an integer chosen from 0 and 1,
n is an integer chosen from 1, 2, 3, 4, 5 and 6,
m is an integer chosen from 2, 3 and 4, it being possible for m to take different values within the different groups —[NH—CS—NH—(CH) m ]—,
R′ represents a group of general formula (II):
in which q is an integer chosen from 1, 2, 3, 4, 5 and 6, and p is an integer chosen from 2, 3 and 4, it being possible for p to take different values within the different groups —[(CH 2 ) p —NH—CS—NH]—,
R represents either a hydrogen atom or a group of general formula (II) as defined above, it being understood that when n is 1 and l is 0, then at least one group R is of formula (II),
X, in the formulae (I) and (II), represents a saturated or unsaturated, linear or cyclic aliphatic group, comprising 1 to 8 carbon atoms, a mercaptomethyl (—CH 2 SH) group, or alternatively a hydrophilic chain chosen from the groups:
—(CH 2 ) x —(CHOH) u —H with x an integer chosen from 1 to 10 and u an integer chosen from 1, 2, 3, 4, 5 and 6, or alternatively,
—(OCH 2 CH 2 O) v —H with v an integer chosen from 1, 2 and 3, it being understood that no more than one substituent X, both in the formulae (I) and (II), represents a hydrophilic chain,
Y represents a spacer,
and L represents:
either a group —N(R 1 )R 2 with R 1 and R 2 which represent, independently of each other, a hydrogen atom or alternatively a fatty aliphatic chain, or alternatively a group of formula —(CH 2 ) t —OZ with t representing an integer chosen from 11, 12, 13, 14 or 15 and Z represents a sugar, a polyol or a PEG, it being understood that at least one of R 1 and R 2 is different from hydrogen,
or a group —OR 3 , with R 3 which represents a steroid derivative.
According to the present invention, the term “spacer” is understood to mean any chemical group which makes it possible both to provide the linkage between the polythiourea part and the lipid part of the molecule, and to keep these two parts apart so as to attenuate any undesirable interruption between them. Preferred spacers may for example consist of one or more chemical functional groups chosen from alkyls having 1 to 6 carbon atoms, ketone, ester, ether, amide, amidine, carbamate or thiocarbamate functional groups, glycerol, urea, thiourea, or else aromatic rings. For example, the spacer may be chosen from the groups of formula:
—NH—C(O)—CH 2 —CH 2 —
or:
—(CH 2 —) i —W—(CH 2 ) j —
in which i and j are integers chosen between 1 and 6 inclusive and W is a group chosen from ketone, ester, ether, amide, amidine, carbamate or thiocarbamate functional groups, glycerol, urea, thiourea, or alternatively aromatic rings.
For the purposes of the present invention, the expression “fatty aliphatic chains” is understood to mean alkyl groups containing 10 to 22 carbon atoms which are saturated or unsaturated and optionally containing one or more heteroatoms, provided that said fatty aliphatic chains exhibit lipid properties. Preferably, they are linear or branched alkyl groups containing 10 to 22 carbon atoms and 1, 2 or 3 unsaturations. Preferably, said alkyl groups comprise 10, 12, 14, 16, 18, 20 or 22 carbon atoms. There may be mentioned more particularly the aliphatic groups —(CH 2 ) 11 CH 3 , —(CH 2 ) 13 CH 3 , (CH 2 ) 15 CH 3 and —(CH 2 ) 17 CH 3 .
The term “sugar” is understood to mean, for the purposes of the invention, any molecule consisting of one or more saccharides. There may be mentioned, by way of example, sugars such as pyranoses and furanoses, for example glucose, mannose, rhamnose, galactose, fructose or alternatively maltose, lactose, saccharose, sucrose, fucose, cellobiose, allose, laminarabiose, gentiobiose, sophorose, melibiose, and the like. Preferably, the sugar(s) are chosen from glucose, mannose, rhamnose, galactose, fructose, lactose, saccharose and cellobiose. Furthermore, it may also involve so-called “complex” sugars, that is to say several sugars which are covalently coupled to each other, each sugar being preferably chosen from the list cited above. As suitable polysaccharides, there may be mentioned dextran, α-amylose, amylopectin, fructans, mannans, xylans and arabinans. Some preferred sugars may in addition interact with the cell receptors, such as for example certain types of lectin.
According to the invention, the term “polyol” is also understood to mean any linear, branched or cyclic hydrocarbon molecule comprising at least two hydroxyl functional groups. There may be mentioned by way of example glycerol, ethylene glycol, propylene glycol, tetritols, pentitols, cyclic pentitols (or quercitols), hexitols such as mannitol, sorbitol, dulcitols, cyclic hexitols or inositols, and the like (Stanek et al., The Monosaccharides Academic Press, pp. 621-655 and pp. 778-855). According to a preferred aspect; the polyols are chosen from the alcohols of general formula:
for which s is chosen from 2, 3, 4, 5 and 6.
When the compounds of general formula (I) according to the invention contain a polyethylene glycol (PEG) group, the latter generally comprises between 2 and 120 —OCH 2 CH 2 O— units, and preferably between 2 and 80 —OCH 2 CH 2 O— units. This may include simple PEGs, that is to say whose chain ending ends with a hydroxyl group, or else PEG whose terminal group is chosen from alkyls, for example methyl.
For the purposes of the present invention, the expression “steroid derivatives” is understood to mean polycyclic compounds of the cholestane type. These compounds may be natural or otherwise and are more preferably chosen from cholesterol, cholestanol, 3-α-5-cyclo-5-α-cholestan-6-β-ol, cholic acid, cholesteryl formate, chotestanyl formate, 3α,5-cyclo-5α-cholestan-6β-yl formate, cholesterylamine, 6-(1,5-dimethylhexyl)-3a,5a-dimethylhexadecahydrocyclopenta[a]cyclopropa[2,3]cyclopenta[1,2-f]naphthalen-10-ylamine, or cholestanylamine.
According to a preferred variant of the invention, the transfecting compounds have the general formula (lII):
in which X, m, n and Y are as defined above in general formula (I), with the exception of n which is different from 1, and R 1 and R 2 represent, independently of each other, a hydrogen atom or else a fatty aliphatic chain, it being understood that at least one of R 1 and R 2 is different from hydrogen.
More preferably still, the transfecting compounds of the invention have the general formula (IV):
in which m, n and Y are as defined above in general formula (I), with the exception of n which is different from 1, and R 1 and R 2 represent, independently of each other, a hydrogen atom or else a fatty aliphatic chain, it being understood that at least one of R 1 and R 2 is different from hydrogen.
It is understood that the present invention also relates to the isomers of the products of general formula (I) when they exist, as well as mixtures thereof.
The preparation of the compounds of general formula (I) according to the present invention is carried out using the following steps, in the order presented or according to any other known and equally suitable variant, using conventional organic synthesis techniques, in solution or on solid supports, which are well known to a person skilled in the art:
1) Production of the Lipid Part L
When the lipid part L of the compounds of general formula (I) is represented by a group —N(R 1 )R 2 with R 1 and/or R 2 which represent a fatty aliphatic chain, the amine of formula HN(R 1 )R 2 is first of all formed. Said amine may be obtained by condensing a carboxylic acid and an amine, one containing the substituent R 1 and the other the substituent R 2 , to form the corresponding amide, followed by reduction of said amide thus obtained.
Amide formation is advantageously carried out by mixing constituents and melting, by heating at a temperature of greater than the melting point of the substances involved, in general between 20° C. and 200° C., followed by elimination of the water produced by dehydrating the medium; or more advantageously in the presence of a desiccating agent such as for example phosphorus pentoxide or any other substance which can absorb water. The formation of this intermediate amide may also be carried out using a variant of this method or another method for forming an amide (such as for example peptide-coupling type) involving carboxylic acids or derivatives thereof, and varying conditions and reagents [R. C. Larock, Comprehensive Organic Transformations, VCH Publishers] well known to a person skilled in the art.
The reduction of the amide previously obtained to an amine of formula HN(R 1 )R 2 may be carried out for example using a reducing agent such as lithium aluminum hydride, or any other hydride or reducing agent effective in this case. The procedure is then preferably carried out in an aprotic solvent (for example tetrahydrofuran or ethers) at a temperature below the boiling point of the solvent or under a dry and/or inert atmosphere.
According to another variant, the lipid part designated as HN(R 1 )R 2 may be commercially available.
When R 1 and/or R 2 represent(s) a group of formula —(CH 2 ) t —OZ, the procedure is carried out as described above for forming the alkyl part, followed by simple coupling with a commercial PEG, polyol or sugar according to conventional techniques known to a person skilled in the art.
When the lipid part L of the compounds of the general formula (I) is represented by a group —OR 3 , the latter is preferably chosen from commercially available products.
2) Grafting of the Spacer Y
The spacer Y is then attached to the lipid part L obtained in the preceding stage according to conventional techniques known to a person skilled in the art. According to a preferred variant, an amide bond is made by N-acylation of the lipid part L in an appropriate solvent such as dichloromethane, chloroform, tetrahydrofuran, or any other ether, at a temperature below the boiling point of the solvent, and under a dry and/or inert atmosphere. This reaction is preferably carried out in the presence of an amine-containing base such as N,N-dimethylaminopyridine, or in the presence of this base mixed with non-nucleophilic amine-containing bases such as triethylamine or else ethyl diisopropylamine. Pyridine may also be used, alone or mixed with another base, diluted with one of the solvents mentioned or used itself as solvent.
3) Formation of the Polythiourea Chain
The third part of the synthesis of the compounds of general formula (I) consists in the successive introduction of the thiourea units. This will be carried out in a series of reactions which may be repeated as many times as necessary in order to obtain the desired polythiourea part. According to a preferred method, the procedure is carried out in the following manner:
A) There is first of all grafted onto the Y—C(O)—L obtained in the preceding stage the first part of the unit in the form of a member —HN—(CHR) m — group. For that, the procedure is advantageously carried out starting with a diamine-containing member of formula H 2 N—(CHR) m —NH 2 in the presence of a coupling agent, for example 1-benzotriazolyloxytris(pyrrolidino)phosphonium hexafluorophosphate (PyBOP), 1-benzotriazolyloxytris(dimethylamino)phosphonium hexafluorophosphate (BOP), O-(1H-benzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate or tetrafluoroborate (HBTU or TBTU), dicyclohexylcarbodiimide (DCC), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC), or else 1-(3-trimethylammoniopropyl)-3-ethylcarbodiimide iodide, supported or otherwise. This coupling is carried out in a suitable solvent, for example dichloromethane, chloroform, tetrahydrofuran or any other ether, at a temperature below the boiling point of a solvent, and under a dry and/or inert atmosphere. The procedure is also carried out in the presence of a non-nucleophilic amine-containing base, for example ethyldiisopropylamine, triethylamine or else triisopropylamine. If the nature of the lipid part and of the spacer is compatible, a sequence of the SCN—(CHR) m — type, or a precursor, may be grafted, thus making it possible to continue the synthesis through a stage such as that described below in C),
B) The product obtained in the preceding stage is then converted, according to a preferred technique, to isothiocyanate by treating with carbon disulfide (CS 2 ), or with any other reagent known to the person skilled in the art for obtaining such a functionality [H. Ulrich, Chemistry and Technology of Isocyanates, Wiley (1996). The Chemistry of Cyanates and their Thio Derivatives, S. Patai Ed., Wiley (1977). S. Ozaki, Recent Advances in Isocyanate Chemistry, Chem. Rev. 72, 457 (1972)]. The reaction is advantageously carried out in a solvent such as for example tetrahydrofuran, or any other compatible ether solvent, at a temperature varying between that of the cooling mixtures and about 20° C. The procedure is also carried out in the presence of an agent capable of promoting the reaction and/or of trapping the hydrogen sulfide released during the reaction, for example dicyclohexylcarbodiimide (DCC).
C) The thiourea unit is then formed from the isothiocyanate obtained in the preceding stage so as to allow, where appropriate, the introduction of another segment of formula —CHR) m —. Advantageously, a diamine of formula H 2 N—(CHR) m —NH 2 , optionally protected, is reacted, in its neutral form or in the form of an acid salt, with the isothiocyanate obtained in the preceding stage. This reaction is optionally carried out in the presence of a non-nucleophilic amine-containing base, for example triethylamine, ethyldiisopropylamine, triisopropylamine or else 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU). The procedure is preferably carried out in a suitable solvent such as dichloromethane, chloroform, tetrahydrofuran or any other compatible ether or solvent, at a temperature which may be between that of the cooling mixtures and the reflux temperature of the solvent.
Stages B) and C) described above are then repeated sequentially and in the required order until the desired structure is obtained, so as to introduce the desired unit in n copies. To obtain branched structures, the procedure is carried out in a similar manner by introducing, at the appropriate time, the molecule(s) required to obtain a substitution R as described by formula (II).
4) Ending of the Polythiourea Part by Introducing the Substituent X
The last stage allowing the ending of the polythiourea-type chain(s) consists in introducing the substituent X. For that, conventional grafting methods known to a person skilled in the art, chosen according to the nature of the substituent X, are used. For example, when X represents an alkyl, the procedure is carried out by reacting an alkyl isothiocyanate, in the presence, when necessary, of a non-nucleophilic amine-containing base such as for example triethylamine, ethyldiisopropylamine, triisopropylamine or else 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU). The reaction is performed in a suitable solvent, for example dichloromethane, chloroform, tetrahydrofuran or any other compatible ether, at a temperature between the temperature of the cooling mixtures and the reflux temperature of the solvent.
Naturally, when the various substituents can interfere with the reaction, it is preferable to protect them beforehand with compatible radicals which can be put in place and removed without affecting the remainder of the molecule. For that, the procedure is carried out according to conventional methods known to a person skilled in the art, and in particular according to the methods described in T. W. Greene, Protective Groups in Organic Synthesis, Wiley-lnterscience, in McOmie, Protective Groups in Organic Chemistry, Plenum Press, or in P. J. Kocienski, Protecting Groups, Thieme.
Moreover, each stage of the method of preparation may be followed, where appropriate, by stages for separating and purifying the compound obtained according to any method known to a person skilled in the art.
Preferred compounds according to the present invention are:
The 3-(2-{3-[2-(3-{2-[3-(ditetradecylcarbamoyl)propionylamino]ethyl}thioureido)ethyl]thioureido}ethyl)-1-methylthiourea, designated herein as DTTU or as DT-3TU, corresponds to the general formula (I), wherein X=—CH 3 ; m=2; R=H; n=3; l=0; Y=NH—CO—CH 2 —CH 2 ; and L=—N(R 1 )R 2 où R 1 =R 2 =C 14 H 29 . Designation of this compound as DT-3TU, refers to the three thiourea groups comprised therein; in addition, examples of this nomenclature include, DT-4TU comprising four thioureas, DT-2TU comprising two thioureas, etc.
The 3-(2-{3-[2-(3-{2-[3-(2-{3-[ditetradecyl-carbamoyl]propionylamino}-ethyl)-thioureido]-ethyl}-thioureido)-ethyl]-thioureido}-ethyl)-1-methylthiourea or DT-4TU is according to the general formula (I), wherein X=—CH3; m=2; R=H; n=4; and l==0; Y=NH—CO—CH 2 —CH 2 ; and L=—N(R 1 )R 2 where R 1 =R 2 =C 14 H 29 .
The DT-3TU diol or Synthesis of [2-(3-{2-[3-(2-{3-[2-(3-(ditetradecyl-carbamoyl)propionylamino)-ethyl]-thioureido}ethyl)-thioureido]-ethyl}-thioureido)-ethyl]-propane-1,2-diol, is according to the general formula (I), wherein:
m=2
R=H
n=3
l=0
Y=NH—CO—CH 2 —CH 2 ; and
L=—N(R 1 )R 2 where R 1 =R 2 =C 14 H 29 .
The DT-2TU diol or [2-(3-{2-[3-(ditetradecyl-carbamoyl)propionylamino]-ethyl}-thioureido)-ethyl]-propane-1,2-diol Where according to the general formula (I), wherein
m=2
R=H
n=2
l=0
Y=NH—CO—CH 2 —CH 2 ; and
L=—N(R 1 )R 2 where R 1 =R 2 =C 14 H 29
Another subject of the invention relates to the compositions comprising a transfecting compound according to the invention and a nucleic acid. The respective quantities of each component may be easily adjusted by a person skilled in the art according to the transfecting compound used, the nucleic acid and the desired applications (in particular the type of cells to be transfected).
For the purposes of the invention, the expression “nucleic acid” is understood to mean both a deoxyribonucleic acid and a ribonucleic acid. They may be natural or artificial sequences, and in particular genomic DNA (gDNA), complementary DNA (cDNA), messenger RNA (mRNA), transfer RNA (tRNA), ribosomal RNA (rRNA), hybrid sequences such as DNA/RNA chimeroplasts or synthetic or semisynthetic sequences, and oligonucleotides which are modified or otherwise. These nucleic acids may be of human, animal, plant, bacterial or viral origin and the like. They may be obtained by any technique known to persons skilled in the art, and in particular by the screening of libraries, by chemical synthesis or by mixed methods including the chemical or enzymatic modification of sequences obtained by the screening of libraries. They may be chemically modified. In general, they contain at least 10, 20, 50 or 100 consecutive nucleotides, and preferably at least 200 consecutive nucleotides. More preferably still, they contain at least 500 consecutive nucleotides.
As regards more particularly deoxyribonucleic acids, they may be single- or double-stranded, as well as short oligonucleotides or longer sequences. In particular, the nucleic acids advantageously consist of plasmids, vectors, episomes, expression cassettes and the like. These deoxyribonucleic acids may carry a prokaryotic or eukaryotic replication origin which is functional or otherwise in the target cell, one or more marker genes, sequences for regulating transcription or replication, genes of therapeutic interest, anti-sense sequences which are modified or otherwise, regions for binding to other cellular components, and the like.
Preferably, the nucleic acid comprises one or more genes of therapeutic interest under the control of regulatory sequences, for example one or more promoters and a transcriptional terminator which are active in the target cells.
For the purposes of the invention, the expression gene of therapeutic interest is understood to mean in particular any gene encoding a protein product having a therapeutic effect. The protein product thus encoded may in particular be a protein or a peptide. This protein product may be exogenous, homologous or endogenous in relation to the target cell, that is to say a product which is normally expressed in the target cell when the latter has no pathological condition. In this case, the expression of a protein makes it possible, for example, to palliate an insufficient expression in the cell or the expression of a protein which is inactive or weakly active because of a modification, or to overexpress said protein. The gene of therapeutic interest may also encode a mutant of a cellular protein, having increased stability, modified activity and the like. The protein product may also be heterologous in relation to the target cell. In this case, an expressed protein may, for example, supplement or provide an activity which is deficient in the cell, allowing it to combat a pathological condition, or to stimulate an immune response.
Among the therapeutic products for the purposes of the present invention, there may be mentioned more particularly enzymes, blood derivatives, hormones, lymphokines and cytokines as well as their inhibitors or their antagonists: interleukins, interferons, TNF, antagonists of interleukin 1, soluble receptors for interleukin 1 or TNFα, and the like (FR 92/03120), growth factors, neuro-transmitters or their precursors or synthesis enzymes, trophic factors (BDNF, CNTF, NGF, IGF, GMF, aFGF, bFGF, NT3, NT5, HARP/pleiotrophin and the like), apolipoproteins (ApoAI, ApoAIV, ApoE, and the like, FR 93/05125), dystrophin or a minidystrophin (FR 91/11947), the CFTR protein associated with cystic fibrosis, tumor suppressor genes (p53, Rb, Rap1A, DCC, k-rev, and the like, FR 93/04745), genes encoding factors involved in coagulation (Factors VII, VII, IX), the genes involved in DNA repair, suicide genes (thymidine kinase, cytosine deaminase), the genes for hemoglobin or other protein carriers, metabolic enzymes, catabolic enzymes and the like.
The nucleic acid of therapeutic interest may also be a gene or an anti-sense sequence or a DNA encoding an RNA with ribosome function, whose expression in the target cell makes it possible to control the expression of genes or the transcription of cellular mRNAs. Such sequences can, for example, be transcribed in the target cell into RNAs which are complementary to cellular mRNAs and thus block their translation to protein, according to the technique described in Patent EP 140 308. The therapeutic genes also comprise the sequences encoding ribozymes, which are capable of selectively destroying target RNAs (EP 321 201).
As indicated above, the nucleic acid may also comprise one or more genes encoding an antigenic peptide, which is capable of generating an immune response in humans or in animals. In this specific embodiment, the invention allows the production of vaccines or the carrying out of immunotherapeutic treatments applied to humans or to animals, in particular for treating or preventing infections, for example viral or bacterial infections, or cancerous states. They may be in particular antigenic peptides specific for the Epstein-Barr virus, the HIV virus, the hepatitis B virus (EP 185 573), the pseudo-rabies virus, the syncitia forming virus, other viruses, or antigenic peptides specific for tumors (EP 259 212).
Preferably, the nucleic acid also comprises sequences allowing the expression of the gene of therapeutic interest and/or the gene encoding the antigenic peptide in the desired cell or organ. They may be sequences which are naturally responsible for the expression of the gene considered when these sequences are capable of functioning in the infected cell. They may also be sequences of different origin (responsible for the expression of other proteins, or even synthetic). In particular, they may be promoter sequences of eukaryotic or viral genes. For example, they may be promoter sequences derived from the genome of the cell which it is desired to infect. Likewise, they may be promoter sequences derived from the genome of a virus. In this regard, there may be mentioned, for example, the promoters of the E1A, MLP, CMV and RSV genes, and the like. In addition, these expression sequences may be modified by the addition of activating or regulatory sequences, and the like. The promoter may also be inducible or repressible.
Moreover, the nucleic acid may also comprise, in particular upstream of the gene of therapeutic interest, a signal sequence directing the therapeutic product synthesized in the secretory pathways of the target cell. This signal sequence may be the natural signal sequence of the therapeutic product, but it may also be any other functional signal sequence, or an artificial signal sequence. The nucleic acid may also comprise a signal sequence directing the synthesized therapeutic product towards a particular compartment of the cell.
The compositions according to the invention may, in addition, comprise one or more adjuvants capable of combining with the transfecting compound/nucleic acid complexes and of improving the transfecting power thereof. In another embodiment, the present invention therefore relates to compositions comprising a nucleic acid, a transfecting compound as defined above and at least one adjuvant capable of combining with the transfecting compound/nucleic acid complexes and of improving the transfecting power thereof. The presence of this type of adjuvant (lipids, peptides, proteins or polymers for example) may make it possible advantageously to increase the transfecting power of the compounds. In this regard, the compositions of the invention may comprise, as adjuvant, one or more neutral lipids, which possess in particular the property of forming lipid aggregates. The term “lipid aggregate” is a generic term which includes liposomes of any type (both unilamellar and multilamellar) as well as micelles or else more amorphous aggregates.
More preferably, the neutral lipids used within the framework of the present invention are lipids containing two fatty chains. In a particularly advantageous manner, natural or synthetic lipids which are zwitterionic or lacking ionic charge under physiological conditions are used. They may be chosen more particularly from dioleoylphosphatidylethanolamine (DOPE), oteoylpalmitoyl-phosphatidylethanolamine (POPE), di-stearoyl, -palmitoyl, -myristoylphosphatidyl-ethanolamines as well as their derivatives which are N-methylated 1 to 3 times, phosphatidylglycerols, diacylglycerols, glycosyldiacylglycerols, cerebrosides (such as in particular galactocerebrosides), sphingolipids (such as in particular sphingomyelins) or asialogangliosides (such as in particular asialoGM1 and GM2). Advantageously, the lipid adjuvants used in the context of the present invention are chosen from DOPE, DOPC or cholesterol.
These different lipids may be obtained either by synthesis or by extraction from organs (for example the brain) or from eggs, by conventional techniques well known to persons skilled in the art. In particular, the extraction of the natural lipids may be carried out by means of organic solvents (see also Lehninger, Biochemistry).
Preferably, the compositions of the invention comprise from 0.01 to 20 equivalents of adjuvants for one equivalent of nucleic acid in mol/mol and, more preferably, from 0.5 to 5 molar equivalents.
According to another alternative, the adjuvants mentioned above making it possible to improve the transfecting power of the compositions according to the present invention, in particular the peptides, proteins or certain polymers, such as polyethylene glycol, may be conjugated with the transfecting compounds according to the invention, and not simply mixed. In this case, they are covalently linked either to the substituent X in the general formula (I), or to the end of the alkyl chain(s) R 1 and/or R 2 when the latter are fatty aliphatic chains. It is also advantageous to use as adjuvant, a polyethylene glycol covalently linked to cholesterol (chol-PEG). In effect, when such adjuvant is used with transfectant compositiosn according to the present invention, resulting particles have a smaller size, thereby decreasing aggregation thereof, and increasing their half-life in the blood circulation. Amount of transfectant DT-3TU used according to the present invention is such that particles have a size inferior to 500 nm. Preferred amount of DT-3TU used is at least equal to 40 nmol of lipids DT-3TU/μg of DNA (See Examples 11, 13, and 14 herein below).
According to a particularly advantageous embodiment, the compositions of the present invention comprise, in addition, a targeting element which makes it possible to orient the transfer of the nucleic acid. This targeting element may be an extracellular targeting element which makes it possible to orient the transfer of the nucleic acid toward certain cell types or certain desired tissues (tumor cells, hepatic cells, hematopoietic cells and the like). It may also be an intracellular targeting element which makes it possible to orient the transfer of the nucleic acid toward certain preferred cellular compartments (mitochondria, nucleus and the like). The targeting element may be mixed with the transfecting compounds according to the invention and with the nucleic acids, and in this case, the targeting element is preferably covalently linked to a fatty alkyl chain (at least 10 carbon atoms) or to a polyethylene glycol. According to another alternative, the targeting element is covalently linked to the transfecting compound according to the invention either at the level of the substituent X or on the spacer Y, or else at the end of R 1 and/or R 2 when the latter represent fatty aliphatic chains. Finally, the targeting element may also be linked to the nucleic acid as was specified above.
Among the targeting elements which may be used within the framework of the invention, there may be mentioned sugars, peptides, proteins, oligonucleotides, lipids, neuromediators, hormones, vitamins or derivatives thereof. Preferably, they are sugars, peptides, vitamins or proteins such as for example antibodies or antibody fragments, ligands of cell receptors or fragments thereof, receptors or receptor fragments. For example, they may be ligands of growth factor receptors, cytokine receptors, cellular lectin-type receptors, folate receptors, or RGD sequence-containing ligands with an affinity for the receptors for adhesion proteins such as the integrins. There may also be mentioned the receptors for transferin, HDLs and LDLs, or the folate transporter. The targeting element may also be a sugar which makes it possible to target lectins such as the receptors for asialoglycoproteins or for sialydes, such as the Sialyl Lewis X, or alternatively an Fab fragment of antibodies, or a single-chain antibody (ScFv).
The subject of the invention is also the use of the transfecting compounds as defined above for transferring nucleic acids into cells in vitro, in vivo or ex vivo. More precisely, the subject of the present invention is the use of the transfecting compounds according to the invention for the preparation of a medicament intended for treating diseases, in particular diseases resulting from a deficiency in a protein or nucleic product. The polynucleotide contained in said medicament encodes said protein or nucleic product, or constitutes said nucleic product, capable of correcting said diseases in vivo or ex vivo.
For uses in vivo, for example in therapy or for studying the regulation of genes or the creation of animal models of pathological conditions, the compositions according to the invention can be formulated for administration by the topical, cutaneous, oral, rectal, vaginal, parenteral, intranasal, intravenous, intra-muscular, subcutaneous, intraocular, transdermal, intratracheal or intraperitoneal route, and the like. Preferably, the compositions of the invention contain a vehicle which is pharmaceutically acceptable for an injectable formulation, in particular a direct injection into the desired organ, or for administration by the topical route (on the skin and/or the mucous membrane). They may be in particular isotonic sterile solutions, or dry, in particular freeze-dried, compositions which, upon addition, depending on the case, of sterilized water or of physiological saline, allow the constitution of injectable solutions. The nucleic acid doses used for the injection as well as the number of administrations may be adapted according to various parameters, and in particular according to the mode of administration used, the relevant pathological condition, the gene to be expressed, or the desired duration of treatment. As regards more particularly the mode of administration, it may be either a direct injection into the tissues, for example at the level of the tumors, or an injection into the circulatory system, or a treatment of cells in culture followed by their reimplantation in vivo by injection or transplantation. The relevant tissues within the framework of the present invention are, for example, the muscles, skin, brain, lungs, liver, spleen, bone marrow, thymus, heart, lymph, blood, bones, cartilages, pancreas, kidneys, bladder, stomach, intestines, testicles, ovaries, rectum, nervous system, eyes, glands, connective tissues, and the like.
Another subject of the present invention relates to a method of transferring nucleic acids into cells comprising the following steps:
(1) bringing the nucleic acid into contact with a transfecting compound according to the present invention, to form a complex, and
(2) bringing the cells into contact with the complex formed in (1).
The invention relates, in addition, to a method of treating the human or animal body comprising the following steps:
(1) bringing the nucleic acid into contact with a transfecting compound according to the present invention, to form a complex, and
(2) bringing the cells of the human or animal body into contact with the complex formed in (1).
The cells may be brought into contact with the complex by incubating the cells with said complex (for uses in vitro or ex vivo), or by injecting the complex into an organism (for uses in vivo). In general, the quantity of nucleic acid intended to be administered depends on numerous factors such as for example the disease to be treated or to be prevented, the actual nature of the nucleic acid, the strength of the promoter, the biological activity of the product expressed by the nucleic acid, the physical condition of the individual or of the animal (weight, age and the like), the mode of administration and the type of formulation. In general, the incubation is preferably carried out in the presence, for example, of 0.01 to 1000 μg of nucleic acid per 10 6 cells. For administration in vivo, nucleic acid doses ranging from 0.01 to 50 mg may for example be used. The administration may be carried out as a single dose or repeated at intervals.
In the case where the compositions of the invention contain, in addition, one or more adjuvants as defined above, the adjuvant(s) may be mixed beforehand with the transfecting compound according to the invention and/or the nucleic acid. Alternatively, the adjuvant(s) may be administered before the administration of the nucleolipid complexes.
According to another advantageous alternative, the tissues may be subjected to a chemical or physical treatment intended to improve the transfection. In the case of the physical treatment, the latter may use electrical pulses as in the case of electrotransfer, or else mechanical forces as in the case of sodoporation.
The present invention thus provides a particularly advantageous method for transferring nucleic acids in vivo, in particular for the treatment of diseases, comprising the in vivo or in vitro administration of a nucleic acid encoding a protein or which can be transcribed into a nucleic acid capable of correcting said disease, said nucleic acid being combined with a transfecting compound according to the invention under the conditions defined above.
The transfecting compounds of the invention are particularly useful for transferring nucleic acids into primary cells or into established lines. They may be fibroblast cells, muscle cells, nerve cells (neurons, astrocytes, glial cells), hepatic cells, hematopoietic cells (lymphocytes, CD34, dendritic cells, and the like), epithelial cells and the like, in differentiated or pluripotent form (precursors).
Another subject of the present invention also relates to the transfection kits which comprise one or more transfecting compounds according to the invention and/or mixtures thereof. Such kits may be provided in the form of a packaging which is compartmented so as to receive various containers such as for example vials or tubes. Each of these containers comprises the various elements necessary to carry out the transfection, individually or mixed: for example one or more transfecting compounds according to the invention, one or more nucleic acids, one or more adjuvants, cells, and the like.
In addition to the preceding arrangements, the present invention also comprises other characteristics and advantages which will emerge from the examples and figures below, which should be considered as illustrating the invention without limiting its scope. In particular, the applicant proposes, without limitation, an operating protocol as well as reaction intermediates which may be used to prepare the transfecting compounds according to the invention. Of course, it is within the capability of persons skilled in the art to draw inspiration from this protocol or intermediate products to develop similar methods so as to arrive at these same compounds.
ABBREVIATIONS USED
EtBr: ethidium bromide
DCC: dicyclohexylcarbodiimide
DPPC: 1,2-dipalmitoyl-sn-glycero-3-phosphocholine
DTTU: 3-(2-{3-[2-(3-{2-[3-(ditetradecylcarbamoyl)propionylamino]-ethyl}thioureido)ethyl]thioureido}ethyl)-1-methylthiourea (also designated DT-3TU)
EPC: L-α-phosphatidylcholine 95% (egg)
PyBOP: benzotriazol-1-yloxytripyrrolidinophosphonium hexafluorophosphate
TBE: tris-borate-EDTA
TFA: trifluoroacetic acid
THF: tetrahydrofuran
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 : Variation of the level of fluorescence (in %) as a function of the quantity of EPC/DTTU mixture (in nmol) per μg of nucleic acid and as a function of the quantity of EPC alone (in nmol) per μg of nucleic acid (control mixture).
FIG. 2 : Variation of the level of fluorescence (in %) as a function of the quantity of DPPC/DTTU mixture (in nmol) per μg of nucleic acid and as a function of the quantity of DPPC alone (in nmol) per μg of nucleic acid (control mixture).
FIG. 3 : Agarose gel (0.8%/TBE) showing the compaction of the plasmid pXL3031 (μg) as a function of the quantity of EPC/DTTU liposome (in nmol) used.
FIG. 4 : Zeta potential (in mV) corresponding to the potential at the surface of the DPPC/DTTU-DNA liposomes as a function of the quantity of lipid (nmol) per μg of nucleic acid.
FIG. 5 : Efficiency of in vitro transfection of HeLa cells with complexes formed between the DNA and the DTTU/DPPC (1:2) liposomes at various lipid/DNA ratios in nmol/μg, with or without serum.
The y-axis represents the expression of luciferase in RLU/μg of protein.
The x-axis indicates the quantity of DTUU (in nmol) per μg of DNA.
FIG. 6 : Level of proteins (as absorbance) of HeLa cells not treated or treated with EPC+DTTU/DNA liposomes at various lipid/DNA ratios in nmol/μg.
FIG. 7 : Schematic representation of the plasmid pXL3031.
FIG. 8 : Agarose gel (0.8%/TBE) showing the compaction of the plasmid pXL3031 (μg) as a function of the quantity of DT-3TU/DPPC nanoemulsions (nmol) used.
FIG. 9 : Agarose gel (0.8%/TBE) showing the compaction of the plasmid pXL3031 (μg) as a function of the quantity of DT-3TU/DPPC/chol-PEG nanoemulsions (nmol) used.
FIG. 10 : Variation of the percentage of DNA compacted as a function of the quantity of DT-4TU/DPPC mixture (in nmol) per μg of nucleic acid in comparison with various amount of DT-3TU/DPPC (in nmol) per μg of nucleic acid.
FIG. 11 : Agarose gel (0.8%/TBE) showing the protection by the DT-3TU/DPPC mixture of the plasmid pXL3031 (μg) against DNAses degradation.
FIG. 12 : Agarose gel (0.8%/TBE) showing the protection by the DT-3TU/DPPC mixture of the plasmid pXL3031 (μg) when placed in serum. Lane 1 corresponds to DNA; lanes 2 and 3 correspond to DNA alone or in presence of 10 nmol/μg of DT-3TU/DPPC nanoemulsions in 150 mM of NaCl, and in 20% of serum (lanes 4 and 5), and in 100% of serum (lanes 6 and 7).
FIG. 13 : Efficiency of in vivo muscle transfection by complexes of DNA and liposomes DT-3TU/DPPC, present in various amounts of lipids/DNA in nmol/μg with or without electrotransfert (e−/e+).
FIG. 14 : In vivo biodistribution of complexes DT-3TU/DPPC/DOPE-Rh/DNA in mouse, after 30 min, 1 h, and 6 h in blood, lungs and RES (liver and spleen). This figure shows that the particles have the property of being furtive: 50% of the complexes are retrieved in the blood circulation after 30 min.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is illustrated by the following nonlimiting examples.
EXAMPLES
Customary reagents and catalysts such as triethylamine, trifluoroacetic acid, p-toluenesulfonic acid, benzotriazol-1-yloxytripyrrolidinophosphonium hexafluorophosphate (PyBOP), dicyclohexylcarbodiimide (DCC), carbon disulfide, tetradecylamine, di-tert-butyl dicarbonate, 4-dimethylaminopyridine, or diisopropylethylamine were commercially available.
The proton nuclear magnetic resonance ( 1 H NMR) spectra were recorded on Bruker 300, 400 and 600 MHz spectrometers. The chemical shifts were expressed in ppm (parts per million) and the multiplicities by the customary abbreviations.
In the text which follows, the nucleic acid used was the plasmid pXL3031 described in the publication Gene Therapy (1999) 6, pp. 1482-1488, which contained the luc gene encoding luciferase under the control of the cytomegalovirus CMV E/P promoter. This plasmid is represented in FIG. 7 . Its size is 3671 bp. The plasmid solution used was diluted to 1.262 g/l in water for injection.
Example 1
Synthesis of DT-3TU
The 3-(2-{3-[2-(3-{2-[3-(ditetradecylcarbamoyl)propionylamino]ethyl}thioureido)ethyl]thioureido}ethyl)-1-methylthiourea, designated herein as DTTU, or DT-3TU, corresponds to the general formula (I), wherein X=—CH 3 ; m=2; R=H; n=3; l=0; Y=NH—CO—CH 2 —CH 2 ; and L=—N(R 1 )R 2 or R 1 =R 2 =C 14 H 29 .
a) Synthesis of ditetradecylamide (1)
131.6 mmol of tetradecanoic acid (30 g) and 140.8 mmol of tetradecylamine (30 g) were mixed in a round-bottomed flask equipped with a magnetic stirrer connected to a collecting flask containing a drying agent (P 2 O 5 ). The reaction mixture was then heated for 4 hours to 170° C. under reduced pressure (50 mmHg). The crude material was then solubilized in THF (700 ml; heated slightly in order to aid solubilization) and then 4 equivalents of Amberlyst-15 resin (8 g) were added in order to bind the excess amine. After stirring for 20 minutes, the solution was filtered and the filtrate was then concentrated to give 55.11 g of a white solid (yield: 99%).
1 H NMR (CDCl 3 ): δ (ppm) 0.88 (t, 6H, J=6.5 Hz, —CH 3 ), 1.25 (m, 42 H, —CH 2 —, 1.47 (m, 2H, CO—CH 2 —CH 2 ), 1.60 (m, 2H, N—CH 2 —CH 2 ), 2.15 (t, 2H, J=7.5 Hz, CO—CH 2 ), 3.23 (dt, 2H, J=7 Hz, N—CH 2 ), 5.50 (s, 1H, NH).
13 C NMR (CDCl 3 ): δ (ppm) 14.09 (C 14 -+C′ 13 ), 22.71 (C 13 +C′ 12 ), 25.90 (C′ 2 ), 26.99 (C 3 ), 29.69 (—CH 2 —), 31.96 (C 12 +C′ 11 ), 36.97 (C′ 1 ), 39.56 (C 1 ), 160 (CO).
b) Synthesis of ditetradecylamine (2)
47 mmol of ditetradecylamide (20 g) were dissolved in 700 ml of anhydrous THF, under nitrogen, in a round-bottomed flask equipped with a condenser and a drying tube. The mixture was cooled to 0° C. and then 89 mmol of lithium aluminum hydride LiAlH 4 (3.4 g) were added. After addition, the mixture was then heated under reflux for 5 hours, with vigorous stirring. Once the reaction was complete, the mixture was cooled to 0° C. in order to carry out the hydrolysis by successive addition of 3.4 ml of water, 6.8 ml of 1N sodium hydroxide and 3.4 ml of water. After stirring for 1 hour at room temperature, the crude reaction material was filtered on a Büchner funnel and the filtrate was concentrated. The product obtained was then purified on 1.5 equivalents of A-15 resin (15 g) in 300 ml of THF, with stirring for 30 minutes. The resin was filtered and redissolved in 300 ml of THF, with addition of 2 equivalents of triethylamine (19.2 ml). After stirring for 30 minutes, the solution was filtered and the filtrate was concentrated to give 17.72 g of a white solid (yield: 92%).
1 H NMR (CDCl 3 ): δ (ppm) 0.87 (t, 6H, J=6.5 Hz, —CH 3 ), 1.25 (m, 44 H, —CH 2 —), 1.46 (m, 4H, N—CH 2 —CH 2 ), 2.58 (t, 4H, J=7 Hz, N—CH 2 ).
13 C NMR (CDCl 3 ): δ (ppm) 14.06 (C 14 ), 22.69 (C 13 ), 27.48 (C 3 ), 28.29 (C 2 ), 29.69 (C 4 -C 11 ), 31.96 (C 12 ), 50.15 (C 1 ).
C) Synthesis of N,N-ditetradecylsuccinamic acid (3)
12.65 mmol of succinic anhydride (1.266 g), 12.65 mmol of 4-dimethylaminopyridine (1.546 g) and 10.75 mmol of ditetradecylamine (4.407 g) were successively added to 125 ml of dichloromethane in a round-bottomed flask. The reaction mixture was stirred for 18 hours at room temperature. Once the reaction was complete, the mixture was extracted with dichloromethane and hydrochloric acid (1N). The organic phase was then washed with brine and dried over magnesium sulfate, filtered and then concentrated to give 4.21 g of product (3) (yield: 66%).
1 H NMR (CDCl 3 ): δ (ppm) 0.85 (t, 6H, J=6.3 Hz, —CH 3 ), 1.23 (m, 44 H, —CH 2 —), 1.48 (m, 4H, N—CH 2 —CH 2 ), 2.64 (s, 4H, CO—CH 2 —CH 2 —CO), 3.22 (m, 4H, N—CH 2 ).
13 C NMR (CDCl 3 ): δ (ppm) 14.08 (C 14 ), 22.69 (C 13 ), 27.74 (C 3 ), 28.10 (CO—CH 2 —CH 2 —CO), 28.92 (C 2 ), 29.67 (C 4 -C 11 ), 30.07 (CO—CH 2 —CH 2 —CO), 31.95 (C 12 ), 46.21 and 47.98 (C 1 ), 4171.46 (CO—NHH(C 14 H 29 ) 2 ), 173.14 (NH—CO).
d) Synthesis of the tert-butyl ester of 2-aminoethylcarbamic acid (4)
18.6 mmol of di-tert-butyl dicarbonate (4 g) were added dropwise to 102.83 mmol of ethylenediamine (6.17 g) in solution in chloroform (20 ml), under nitrogen. The reaction mixture was then stirred for 18 hours at room temperature. Once the reaction was complete, the solution was concentrated. The resulting oil, dissolved in dichloromethane, was washed with a saturated aqueous sodium carbonate solution. The organic phase was then dried over magnesium sulfate, filtered and concentrated. The crude product was purified by flash chromatography (dichloromethane/methanol 9:1). 2.38 g of product (4) were thus obtained (yield: 80%).
1 H NMR (CDCl 3 ): δ (ppm) 1.40 (s, 9H, (CH 3 ) 3 ), 1.52 (s, 2H, NH 2 ), 2.59 (t, 2H, J=5.9 N—CH 2 ), 3.12 (q, 2H, 4 J=5.4 Hz, NHBoc-CH 2 ), 5.1 (s,1H, NHBoc)
— C NMR (CDCl 3 ): δ (ppm) 28.15 (CH 3 ) 3 , 41.67 (CH 2 —NHBoc), 43.46 (CH 2 —NH 2 ), 78.31 (C—(CH 3 ) 3 , 156.21 (C═O).
e) Synthesis of the tert-butyl ester of 2-[3-(ditetra-decylcarbamoyl)propionylamino]ethylcarbamic acid (5)
8.84 mmol of PyBOP (4.601 g), 9.72 mmol of the amine (4) obtained in the preceding stage (1.558 g) and 24.31 mmol of diisopropylethylamine (4.24 ml) were successively added to a solution of 8.84 mmol of the acid (3) obtained above (4.5 g) in 88 ml of dichloromethane. The solution was then stirred for 4 hours at room temperature. At the end of the reaction, the reaction mixture was filtered and then the product was purified by flash chromatography (heptane/ethyl acetate 5:5 and then heptane/ethyl acetate 2:8). 3.79 g of the ester (5) were thus obtained (yield: 66%).
1 H NMR (CDCl 3 ): δ (ppm) 0.87 (t, 6H, J=6.6 Hz, —CH 3 ), 1.25 (m, 44H, —CH 2 —), 1.43 (s, 9H, (CH 3 ) 3 ) 1.48 (m, 4H, N—CH 2 —CH 2 ), 2.56 (t, 2H, J=6.7 Hz, CH 2 3), 2.69 (t, 2H, J=6.2 Hz, CH 2 4), 3.28 (m, 4H, N—CH 2 ), 3.3 (m, 4H, CH 2 1+CH 2 2).
13 C NMR (CDCl 3 ): δ (ppm) 14.07 (C″ 14 ), 22.56 (C″ 13 ), 26.99 ((CH 3 ) 3 ), 27.73 (C″ 3 ), 28.29 (C′ 2 ), 28.59 (C″ 2 ), 29.27 (C″ 4 -C″ 11 ), 29.55 (C′ 3 ), 31.41 (C″ 12 ), 39.85 (C 2 ), 40.39 (C 1 ), 46.21 and 47.98 (C″ 1 ), 78.77 (C(IV)-Boc), 156.33 (CO-Boc), 171.46 (CO—NH(C 14 H 29 ) 2 ), 173.14 (C′ 1 ).
f) Synthesis of 2-[3-(ditetradecylcarbamoyl)propionylamino]ethylamine (6)
12.2 mmol of distilled TFA (0.94 ml) were added to 2.44 ml of the ester (5) obtained in the preceding stage (1.59 g). After two hours, the reaction was complete. The product was coevaporated twice with cyclohexane in a rotary evaporator in the cold state. The yield was quantitative.
1 H NMR (CDCl 3 ): δ (ppm) 0.91 (t, 6H, J=6.6 Hz, —CH 3 ), 1.29 (m, 44H, —CH 2 —), 1.51 (m, 4H, N—CH 2 —CH 2 ), 2.59 (t, 2H, J=6.7 Hz, H′ 3 ), 2.71 (t, 2H, J=6.2 Hz, H′ 3 ), 3.29 (m, 4H, N—CH 2 ), 3.31 (m, 4H, H 1 , H 2 ).
13 C NMR (CDCl 3 ): δ (ppm) 14.00 (C″ 14 ), 22.67 (C′ 13 ), 27.35 (C′ 3 ), 27.95 (C′ 2 ), 28.53 (C 2 ), 29.65 (C″ 4 -C″ 11 ), 30.70 (C′ 3 ), 31.94 (C″ 12 ), 37.83 (C 2 ), 40.08 (C 2 ), 47.85 and 49.42 (C″ 1 ), 171.72 (CO—NH(C 14 H 29 ) 2 ), 173.26 (C′ 1 ).
g) Synthesis of ((1,1-dimethylethoxycarbonyl)amino)ethylisothiocyanate (7)
43.69 mmol of DCC (9.015 g), 297.9 mmol of carbon disulfide (17.9 ml) in 27.5 ml of THF were successively added to a round-bottomed flask. The mixture was cooled to −7° C. with a bath of ice and ammonium chloride NH 4 Cl (4/1). 43.69 mmol of the amine (4) obtained above (7 g) dissolved in 20.5 ml of anhydrous THF were then added dropwise over 30 minutes. The mixture was allowed to return to room temperature and the mixture was kept stirring for 21 hours. After evaporation, diethyl ether was added to precipitate the dicyclohexylurea formed. The solution was filtered, the filtrate was concentrated and then purified by flash chromatography (heptane/ethyl/acetate 80:20) to give 6.357 g of desired product (7) (yield: 72%).
1 H NMR (CDCl 3 ): δ (ppm) 1.38 (s, 9H, (CH 3 ) 3 ), 3.31 (q, 2H, 4 J=5.8 Hz, NHBoc-CH 2 ), 3.59 (t, 2H, J=5.6 Hz, S═C═N—CH 2 ), 5.16 (s, 1H, NHBoc)
13 C NMR (CDCl 3 ): δ (ppm) 28.54 ((CH 3 ) 3 ), 41.03 (CH 2 )—NHBoc), 45.53 (CH 2 —N═C═S), 79.71 (C—(CH 3 ) 3 , 132.72 (C═S), 156.21 (C═O).
h) Synthesis of the tert-butyl ester of 2-(3-{2-[3-(ditetradecylcarbamoyl)propionylamino]ethyl}thioureido)ethylcarbamic acid (8)
9.76 mmol of triethylamine (1.36 ml) were directly added to 2.44 mmol of the amine (6) obtained above (1.62 g) and the mixture was kept stirring for 15 minutes. 24.4 ml of dichloromethane and 2.92 mmol of the isothiocyanate (7) obtained in the preceding stage (0.59 g) were then added. The reaction mixture was stirred at room temperature for 12 hours. The mixture was then evaporated and then purified by flash chromatography (ethyl acetate/heptane 6:4 and then 100% of ethyl acetate). 1.343 g of the desired ester (8) were thus obtained (yield: 73%).
1 H NMR (CDCl 3 ): δ (ppm) 0.67 (t, 6H, J=6.4 Hz, —CH 3 ), 1.05 (m, 44 H, —CH 2 —), 1.26 (s, 9H, CH 3 ) 3 ), 1.35 (m, 4H, N—CH 2 —CH 2 ), 2.31 (m, 2H, H 3 ′ 3 ), 2.49 (m, 2H, H 3 ′ 3 ), 3.06 (m, 4H, N—CH 2 ), 3.11 (m, 4H, H 1 , H″ 2 ), 3.47 (m, 4H, H 2 , H″ 1 ), 7.14 (2H, H thiourea).
13 C NMR (CDCl 3 ): δ (ppm) 13.95 (C 4 ′ 14 ), 22.57 (C 4 ′ 13 ), 26.92 ((CH 3 ) 3 ), 27.07 ( 4 ′C 3 ), 27.78 (C 3 ′ 2 ), 28.39 (C 4 ′2), 28.82 (C 3 ′ 3 ), 29.55 (C 4 ′4-C 4 ′11); 31.83 (C 4 ′12), 39.45 (C″ 2 ), 43.63 (C 2 and C″ 1 ), 46.39 and 48.16 (C 4 ′ 1 ), 79.24 (C(IV)-Boc), 156.53 (CO-Boc), 171.72 (CO—NH(C 14 H 29 ) 2 ), 173.71 (C 3 ′ 1 ), 182.97 (C═S).
i) Synthesis of 2-(3-{2-[3-(ditetradecylcarbamoyl)-propionylamino]ethyl}thioureido)ethylamine (9)
9.86 mmol of distilled TFA (0.76 ml) were added to 1.98 mmol of the product (8) obtained in the preceding stage (1.5 g). After 3 hours, the reaction was complete. The product was coevaporated twice with cyclohexane using a rotary evaporator in the cold state. The yield was quantitative.
1 H NMR (CDCl 3 ): δ (ppm) 0.67 (t, 6H, J=6.4 Hz, —CH 3 ), 1.05 (m, 44 H, —CH 2 —), 1.26 (s. 9H, CH 3 ) 3 ), 1.31 (m, 4H, N—CH 2 —CH 2 ), 2.31 (m, 2H, H 3 ′ 3 ), 2.49 (m, 2H, H 3 ′ 3 ), 3.06 (m, 4H, N—CH 2 ), 3.11 (m, 4H, H 1 , H″ 2 ), 3.44 (m, 4H, H 2 , H″ 1 ), 7.10, (2H, H thiourea).
13 C NMR (CDCl 3 ): δ (ppm) 13.85 (C 4 ′ 14 ), 22.49 (C 4 ′ 13 ), 27.01 (C 4 ′ 3 ), 27.72 (C 3 ′ 2 ), 28.29 (C 4 ′ 2 ), 28.79 (C 3 ′ 3 ), 29.49 (C 4 ′ 4 -C 4 ′ 11 ), 31.77 (C 4 ′ 12 ), 39.42 (C″ 2 ), 43.75 (C 2 and C″ 1 ), 46.29 and 48.09 (C 4 ′ 1 ), 171.72 (CO—NH(C 14 H 29 ) 2 ), 173.71 (C 3 ′ 1 ), 182.97 (C═S).
j) Synthesis of the tert-butyl ester of 2-{3-[2-(3-{2-[3-(ditetradecylcarbamoyl)propionylamino]ethyl}-thioureido)ethyl]thioureido}ethylcarbamic acid (10)
7.92 mmol of triethylamine (1.1 ml) were directly added to 1.98 mmol of the amine (9) obtained in the preceding stage (1.47 g) and the mixture was kept stirring for 15 minutes. 19.8 ml of dichloromethane and 2.38 mmol of the isothiocyanate (7) obtained above (0.461 g) were then added and the reaction was allowed to proceed at room temperature, with stirring, for 12 hours. The mixture was then evaporated and then purified by flash chromatography (ethyl acetate/heptane 6:4 and then ethyl acetate/methanol 98:2). 1.136 g of the desired product (10) were thus obtained (yield: 67%).
1 H NMR (CDCl 3 ): δ (ppm) 0.74 (t, 6H, J=6.6 Hz, —CH 3 ), 1.12 (m, 44 H, —CH 2 —), 1.30 (s, 9H, CH 3 ) 3 ), 1.45 (m, 4H, N—CH 2 —CH 2 ), 2.41 (m, 2H, H 5 ′ 2 ), 2.58 (m, 2H, H 5 ′ 2 ), 3.12 (m, 4H, N—CH 2 ), 3.25 (m, 4H, H 1 , H 4 ′ 2 ), 3.56 (m, 8H, H 2 , H″ 1 , H″ 2 , H 4 ′ 1 ), 7.14 (4H, H thiourea).
13 C NMR (CDCl 3 ): δ (ppm) 14.06 (C 6 ′ 14 ), 22.57 (C 6 ′ 13 ), 27.11 (C 6 ′ 3 ), 26.93 ((CH 3 ) 3 ), 27.79 (C 5 ′ 2 ), 28.38 (C 6 ′ 2 ), 28.81 (C 5 ′ 3 ), 29.56 (C 6 ′ 4 -C 6 ′ 11 ), 31.83 (C 6 ′ 12 ), 39.55 (C 4 ′ 2 ), 43.66 (C 2 , C″ 1 , C″ 2 , C 4 ′ 1 ), 46.49 and 48.23 (C 6 ′ 1 ) 79.28 (C(IV)-Boc), 156.61 (CO-Boc), 171.96 (CO—NH(C 14 H 29 ) 2 ), 173.72 (C 5 ′ 1 ), 182.93 (C═S).
k) Synthesis of 2-{3-[2-(3-{2-[3-(ditetradecyl-carbamoyl)propionylamino]ethyl}thioureido)ethyl]thioureido}ethylamine (11)
5.84 mmol of distilled TFA (0.45 ml) were added to 1.15 mmol of the product (10) obtained in the preceding stage (1 g). After 3 hours, the reaction was complete. The product was coevaporated twice with cyclohexane in a rotary evaporator in the cold state. The yield was quantitative.
1 H NMR (CDCl 3 ): δ (ppm) 0.85 (t, 6H, J=6.6 Hz, —CH 3 ), 1.25 (m, 40 H, —CH 2 —), 1.48 (m, 4H, N—CH 2 —CH 2 ), 1.52 (m, 4H, N—CH 2 —CH 2 —CH 2 ), 2.65 (m, 2H, H, H 5 ′ 2 ), 2.77 (m, 2H, H 5 ′ 3 ), 3.26 (m, 4H, N—CH 2 ), 3.43 (m, 4H, H 1 , H 4 ′ 2 ), 3.85 (m, 8H, H 2 , H″ 1 , H″ 2 , H 4 ′ 1 ), 7.44 (4H, H thiourea).
13 C NMR (CDCl 3 ): δ (ppm) 14.05 (C 6 ′ 14 ), 22.68 (C 6 ′ 13 ), 27.05 (C 6 ′ 3 ), 27.58 (C 5 ′ 2 ), 28.71 (C 6 ′ 2 ), 29.36 (C 5 ′ 3 ), 29.67 (C 6 ′ 4 -C 11 ), 31.94 (C 6 ′ 12 ), 40.49 (C 5 ′ 1 ), 43.49 (C in α of C═S), 47.40 and 49.07 (C 6 ′ 1 ), 172.16 (CO—NH(C 14 H 29 ) 2 ), 174.00 (NH—CO), 182.73 (C═S).
I) Synthesis of DT-3TU (12)
1.12 mmol of triethylamine (0.16 ml) were directly added to 0.28 mmol of the amine (11) obtained in the preceding stage (0.24 g) and the mixture was kept stirred for 15 minutes. 2.8 ml of dichloromethane and 0.34 mmol of methyl isothiocyanate (0.024 g) were then added and the reaction was allowed to proceed at room temperature, with stirring for 12 hours. The mixture was then evaporated and then purified by HPLC (high-performance liquid chromatography) on a C 4 column with the following gradient: initially a water/methanol 95:5 mixture up to 100% of methanol. The product obtained was again purified on a small silica column (ethyl acetate/heptane 80:20 and then 100% of ethyl acetate). 118 mg of DTTU were thus obtained (yield: 51%).
1 H NMR (CDCl 3 ): δ (ppm) 0.86 (t, 6H, J=6.7 Hz, —CH 3 —), 1.24 (m, 40 H, —CH 2 —), 1.44 (m, 4H, N—CH 2 —CH 2 ), 1.54 (m, 4H, N—CH 2 —CH 2 —CH 2 ), 2.52 (m, 2H, H 6 ′ 2 ), 2.67 (m, 2H, H 6 ′ 2 ), 3.05 (m, 3H, terminal —CH 3 ), 3.21 (m, 4H, N—CH 2 ), 3.32 (m, 2H, H 5 ′ 2 ), 3.75 (m, 10H, H′ 1 , H′ 2 , H 3 ′ 1 , H 3 ′ 2 , H 5 ′ 1 ), 7.14 (6H, H thiourea).
13 C NMR (CDCl 3 ): δ (ppm) 14.09 (C 7 ′ 14 ), 22.69 (C 7 ′ 13 ), 27.24 (C 7 ′ 3 ), 27.89 (C 6 ′ 2 ), 28.87 (C 7 ′ 2 ), 29.38 (C 6 ′ 3 ), 29.67 (C 7 ′ 4 -C 7 ′ 11 ), 31.26 (terminal —CH 3 ), 31.94 (C 7 ′ 12 ), 39.71 (C 5 ′ 2 ), 43.63 (C′ 1 , C′ 2 , C 3 ′ 1 , C 3 ′ 2 , C 5 ′ 1 ), 46.67 and 48.40 (C 7 ′ 1 ), 172. 16 (CO—NH(C 14 H 29 ) 2 ),174.00 (C 6 ′ 1 ), 182.73 (C═S).
Example 2
Synthesis of DT-4TU
The 3-(2-{3-[2-(3-{2-[3-(2-{3-[ditetradecyl-carbamoyl]propionylamino}ethyl)-thioureido]-ethyl}-thioureido)-ethyl]-thioureido}-ethyl)-1-methylthiourea or DT-4TU was according to the general formula (I), wherein X=—CH3; m=2; R=H; n=4; and l=0; Y=NH—CO—CH 2 —CH 2 ; and L=—N(R 1 )R 2 where R 1 =R 2 =C 14 H 29 .
For the synthesis of DT-4TU, amine (11) was used as the starting material.
a) Synthesis of the tert-butyl ester of 2-(3-{2-[3-(2-{3-[2-(3-(ditetradecyl-carbamoyl)propionylamino)-ethyl]-thioureido}-ethyl)-thioureido]-ethyl}-thioureido)ethyl carbamic acid (13)
Triethylamine (0.643 ml, 4.6 mmol) was added to the amine (11) (0.8 g, 0.92 mmol) and the mixture was kept under stirring for 15 minutes. Then, CH 2 Cl 2 (9.2 ml) was added to the mixture followed by the addition of isothionate (7) (0.224 g, 1.104 mmol) and the reaction mixture was left to react at room temperature under stirring for 20 hours. The mixture was then evaporated and purified on column chromatography (ethyl acetate/heptane 8:2 followed by ethyl acetate/methanol 90:10); 252 mg of the desired were obtained (46% yield).
1 H NMR (CDCl 3 ): δ (ppm) 0.86 (t, 6H, J=6 Hz, H-14′), 1.25 (m, 44 H, H-4′-H-11′), 1.42 (s, 9H, CH 3 ) 3 ), 1.45 (m, 4H, H-2′), 2.55 (m, 2H, H-2), 2.69 (m, 2H, H-3), 3.22 (m, 4H, H-1′), 3.31 (m, 4H, H-5 et H-15), 3.74 (m, 12H, H-6, H-8, H-9, H-11, H-12, H-14), 7.31 (6H, H thiourea).
13 C NMR (CDCl 3 ): δ (ppm) 14.06 (C-14′), 22.66 (C-13′), 27.21 (C-3′), 27.88 (C-2), 28.50 ((CH 3 ) 3 ), 28.87 (C-2′), 29.64 (C-4′-C-11′), 31.27 (C-3), 31.92 (C-12′), 39.639 (C-5), 40.44 (C-13), 43.73 (C-6, C-8, C-9, C-11, C-12, C-14), 46.64 et 48.38 (C-1′), 79.10 (C-17), 156.63 (C-16), 172.35 (C-1), 174.04 (C-4), 182.65 (C-7, C-10, C-13).
b) Synthesis of 2-(3-{2-[3-(2-{3-[2-(3-(ditetradecyl-carbamoyl)propionylamino)-ethyl]-thioureido}-ethyl)-thioureido]-ethyl}-thioureido)-ethyl amine (14)
Distilled TFA (0.142 ml, 1.84 mmol) was added to the amine boc (13) obtained in the preceding stage (0.22 g, 0.23 mmol). After 6 hours the reaction was complete. The product was coevaporated twice with cyclohexane using a rotary evaporator in the cold state. The product was placed on sodium hydroxide in a dessicator overnight. The yield was quantitative.
1 H NMR (CDCl 3 ): δ (ppm) 0.74 (t, 6H, J=6.6 Hz, H-14′), 1.12 (m, 44 H, H-4′-H-11′), 1.45 (m, 4H, H-2′), 2.41 (m, 2H, H-2), 2.58 (m, 2H, H-3), 3.12 (m, 4H, H-1′), 3.25 (m, 4H, H-5 et H-15), 3.56 (m, 12H, H-6, H-8, H-9, H-11, H-12, H-14), 7.14 (6H, H thiourea).
13 C NMR (CDCl 3 ): δ (ppm) 14.06 (C-14′), 22.57 (C-13′), 27.11 (C-3′), 27.79 (C-2), 28.38 (C-2′), 28.81 (C-4′-C-11′), 29.56 (C-3), 31.83 (C-12′), 39.55 (C-5, C-9), 43.66 (C-6, C-8, C-9, C-11, C-12, C-14), 46.49 et 48.23 (C-1′), 171.96 (C-1), 173.72 (C-4), 182.93 (C-7, C-10, C-13).
c) Synthesis of 3-(2-{3-[2-(3-{2-[3-(2-{3-[ditetradecyl-carbamoyl]propionylamino}-ethyl)-thioureido]-ethyl}-thioureido)-ethyl]-thioureido}-ethyl)-1-methylthiourea (DT-4TU) (15)
Triethylamine (1.38 mmol, 0.19 ml) was directly added to the amine (14) (0.23 mmol, 0.224 g) obtained in the preceding stage and the reaction mixture was kept under stirring for 15 minutes. Then, CH 2 Cl 2 (2.3 ml) and methylisothiocyanate (0.46 mmol, 0.034 g) were added and the reaction mixture was left at room temperature under stirring for 12 hours. The mixture was then evaporated and purified by flash chromatography (100% ethyl acetate followed by ethyl acetate/methanol 95:5). 109 mg of DT-4TU were thus obtained (yield: 51%).
1 H NMR (CDCl 3 ): δ (ppm) 0.88 (t, 6H, J=6.3 Hz, H-14′), 1.26 (m, 44 H, H-4′-H-11′), 1.45 1.45 (m, 4H, H-2′), 1.58 (m, 4H, H-3′), 2.57 (m, 2H, H-2), 2.73 (m, 2H, H-3), 3.03 (m, 3H, H-17), 3.23 (m, 4H, H-1′), 3.31 (m, 2H, H-5), 3.73 (m, 14H, H-6, H-8, H-9, H-11, H-12, H-14, H-15), 7.14 (8H, H thiourea).
13 C NMR (CDCl 3 ): δ (ppm) 14.09 (C-14′), 22.69 (C-13′), 27.24 (C-3′), 27.89 (C-2), 28.87 (C-2′), 29.38 (C-3), 29.67 (C-4′-C-11′), 31.26 (C-17), 31.94 (C-12′), 39.71 (C-5), 43.63 (C-6, C-8, C-9, C-11, C-12, C-14, C-15), 46.67 et 48.40 (C-1′), 172.16 (C-1), 174.00 (C-4), 182.73 (C-7, C-10, C-13, C-16).
Example 3
Synthesis of DT-2TU diol
The DT-2TU diol or [2-(3-{2-[3-(ditetradecyl-carbamoyl)propionylamino]-ethyl}-thioureido)-ethyl]-propane-1,2-diol is defined according to the general formula (I), wherein
m=2
R=H
n=2
l=0;
Y=NH—CO—CH 2 —CH 2 ;
L=—N(R 1 )R 2 where R 1 =R 2 =C 14 H 29
a) Synthesis of 4-isothiocyanatomethyl-2,2-dimethyl-[1,3]dioxalane (16)
DCC (3.146 g, 15.25 mmol) and carbon disulfide (6.253 ml, 104.005 mmol) in THF (9.6075 mL) were successively added to a round-bottomed flask. The mixture was cooled to −7° C. using an ice/NH 4 Cl (4:1) bath and 2,2-dimethyl-1,2-dioxalane-4-methanamine (2 g, 15.25 mmol) dissolved in anhydrous THF (7.1675 mL) was added dropwise over 30 minutes. The reaction mixture was allowed to return to room temperature and was kept under stirring for 21 hours. After evaporation, diethyl ether was added. The mixture was filtered, evaporated and purified by chromatography.
1 H NMR (CDCl 3 ): δ (ppm) 1.33 et 1.44 (s, 3H, H-5, H-6), 3.57 (dd, 1H, J=4.8 Hz, J=1.44 Hz, H-1), 3.69 (dd, 1H, J=4.9 Hz, J=1.44 Hz, H-1′), 3.80 (dd, 1H, J=5.4 Hz et J=8.7 Hz, H-3), 4.09 (dd, 1H, J=6.3 Hz, et J=8.7 Hz, H-3), 4.28 (m, 1H, H-2).
13 C NMR (CDCl 3 ): δ (ppm) 25.17, 26.77 (C-5, C-6), 47.49 (C-1), 66.55 (C-3), 73.70 (C-2), 110.29 (C-4), 132.76 (N═C═S).
b) Synthesis of 2-(3-{2-[3-(ditetradecyl-carbamoyl)propionylamino]-ethyl}-thioureido)-ethyl}-4-ylmethyl-2,2-dimethyl-[1,3]dioxalana (17)
Diisopropylethylamine (0.95 mmol, 0.165 ml) was directly added to the amine (9) (0.19 mmol, 0.146 g) obtained in the preceding stage and the reaction mixture was kept under stirring for 15 minutes. Then, CH 2 Cl 2 (1.9 ml) and isothiocyanate (16) (0.209 mmol, 0.027 g) were added and the reaction mixture was left to react at room temperature under stirring for 12 hours. The mixture was then evaporated and purified by reverse phase liquid chromatography C8 with a gradient from 100% water to 100% acetonitrile. Product (17) was obtained in 49% yield.
1 H NMR (CDCl 3 ): δ (ppm) 0.88 (t, 6H, J=6.3 Hz, H-14′), 1.25 (m, 44 H, H-4′-H-11′), 1,34 et 1.43 (s, 3H, H-15, H-16), 1.48 (m, 4H, H-2′), 1.56 (m, 4H, H-3′), 2.52 (m, 2H, H-2), 2.68 (m, 2H, H-3), 3.23 (m, 4H, H-1′), 3.37 (m, 2H, H-5), 3.73 (m, 8H, H-6, H-8, H-9, H-11), 4.05 (m, 2H, H-13), 4.33 (m, 1H, H-12), 7.14 (4H, H thiourea).
13 C NMR (CDCl 3 ): δ (ppm) 14.06 (C-14′), 22.67 (C-13′), 25.32 (C-3′), 27.00 et 27.17 (C-15, C-16), 27.80 (C-2), 28.56 (C-2′), 28.84 (C-3), 29.66 (C-4′-C-11′), 31.25 (C-17), 31.92 (C-12′), 39.78 (C-5), 43.66 (C-6, C-8, C-9), 44.53 (C-11), 46.73 et 47.13(C-1′), 66.87 (C-136), 74.62 (C-12), 109.05 (C-14), 172.21 (C-1), 174.14 (C-4), 183.32 (C-7, C-10, C-13, C-16).
c) Synthesis of [2-(3-{2-[3-(ditetradecyl-carbamoyl)propionylamino]-ethyl}-thioureido)-ethyl]-propane-1,2-diol (DT-2TUdiol) (18)
The protected diol (17) (0.05 g, 0.05 mmol) was dissolved in 1 mL of HCl 1N/THF (1/1) at room temperature and the reaction mixture was stirred for 18 hours. The reaction mixture was then extracted with dichloromethane (2×5 ml), the organic phases were mixed together and neutralised with sodium hydrogenocarbonate. The aqueous phases were extracted with dichloromethane. The organic phases were dried over magnesium sulphate and then the solvent was evaporated. The product obtained was purified by reverse phase liquid chromatography C8 with a gradient from 100% water to 100% acetonitrile. Product (18) was obtained in 49% yield.
1 H NMR (CDCl 3 ): δ (ppm) 0.88 (t, 6H, J=6.3 Hz, H-14′), 1.26 (m, 44 H, H-4′-H-11′), 1.43 (m, 4H, H-2′), 1.59 (m, 4H, H-3′), 1.79 (s, 2H, OH), 2.50 (m, 2H, H-2), 2.70 (m, 2H, H-3), 3.24 (m, 4H, H-1′), 3.39 (m, 2H, H-5), 3.72 (m, 6H, H-6, H-8, H-9), 3.9 (m, 2H, H-11), 4.22 (m, 2H, H-13), 4.58 (m, 1H, H-12), 7.14 (4H, H thiourea).
13 C NMR (CDCl 3 ): δ (ppm) 14.06 (C-14′), 22.67 (C-13′), 25.32 (C-3′), 27.80 (C-2), 28.56 (C-2′), 28.84 (C-3), 29.66 (C-4′-C-11′), 31.25 (C-17), 31.92 (C-12′), 39.78 (C-5), 43.66 (C-6, C-8, C-9), 45.86 (C-11), 46.73 et 47.13 (C-1′), 63.54 (C-13), 70.97 (C-12), 172.21 (C-1), 174.14 (C-4), 183.32 (C-7, C-10).
Example 4
Synthesis of DT-3TU diol
For the synthesis of DT-3TUdiol, amine (11) was used as the starting material.
The DT-3TU diol or Synthesis of {3-[2-(3-{2-[3-(2-{3-[2-(3-(ditetradecyl-carbamoyl)propionylamino)-ethyl]-thioureidoethyl}-thioureido]-ethyl}-thioureido)-ethyl}-propane-1,2-diol, is according to the general formula (I), wherein:
m=2
R=H
n=3
l=0;
Y=NH—CO—CH 2 —CH 2 ; and
L=—N(R 1 )R 2 where R 1 =R 2 =C 14 H 29
a) Synthesis of 2-(3-{2-[3-(2-{3-[2-(3-(ditetradecyl-carbamoyl)propionylamino)-ethyl]-thioureido}-ethyl)-thioureido]-ethyl}-thioureido)-ethyl-4-ylmethyl-2,2-dimethyl-1,3]dioxalana (19)
Diisopropylethylamine (0.95 mmol, 0.165 ml) was directly added to the amine (11) (0.19 mmol, 0.165 g) obtained in the preceding stage and the reaction mixture was kept under stirring for 15 minutes. Then, CH 2 Cl 2 (1.9 ml) and isothiocyanate (16) (0.209 mmol, 0.027 g) were added and the reaction mixture was left to react at room temperature under stirring for 12 hours. The mixture was then evaporated and purified by reverse phase liquid chromatography C8 with a gradient from 100% water to 100% acetonitrile. Product (19) was obtained in 49% yield.
1 H NMR (CDCl 3 ): δ (ppm) 0.88 (t, 6H, J=6.3 Hz, H-14′), 1.25 (m, 44 H, H-4′-H-11′), 1.34 et 1.43 (s, 3H, H-18, H-19), 1.48 (m, 4H, H-2′), 1.56 (m, 4H, H-3′), 2.52 (m, 2H, H-2), 2.68 (m, 2H, H-3), 3.23 (m, 4H, H-1′), 3.37 (m, 2H, H-5), 3.73 (m, 12H, H-6, H-8, H-9, H-11, H-12, H-14), 4.05 (m, 2H, H-16), 4.33 (m, 1H, H-15), 7.14 (6H, H thiourea).
13 C NMR (CDCl 3 ): δ (ppm) 14.06 (C-14′), 22.67 (C-13′), 25.32 (C-3′),27.00 et 27.17 (C-18, C-19), 27.80 (C-2), 28.56 (C-2′), 28.84 (C-3), 29.66 (C4′-C-11′), 31.25 (C-17), 31.92 (C-12′), 39.78 (C-5), 43.66 (C-6, C-8, C-9, C-11), 44.53 (C-14), 47.73 et 47.13(C-1′), 66.87 (C-16), 74.62 (C-15), 109.05 (C-17), 172.21 (C-1), 174.14 (C-4), 183.32 (C-7, C-10, C-13, C-16).
b) Synthesis of {3-[2-(3-{2-[3-(2-{3-[2-(3-(ditetradecyl-carbamoyl)propionylamino)-ethyl]-thioureido}ethyl)-thioureido]-ethyl}-thioureido)-ethyl}-propane-1,2-diol (DT-3TU diol) (20)
The protected diol (19) (0.05 g, 0.05 mmol) was dissolved in 1 mL of HCl 1N/THF (1/1) at room temperature and the reaction mixture was stirred for 18 hours. The reaction mixture was then extracted with dichloromethane (2×5 ml), the organic phases were mixed together and neutralised with sodium hydrogenocarbonate. The aqueous phases were extracted with dichloromethane. The organic phases were dried over magnesium sulphate and then the solvent was evaporated. The product obtained was purified by reverse phase liquid chromatography C8 with a gradient from 100% water to 100% acetonitrile. Product (18) was obtained in 55% yield.
1 H RMN (CDCl 3 ): δ (ppm) 0.88 (t, 6H, J=6.3 Hz, H-14′), 1.26 (m, 44 H, H-4′-H-11′), 1.43 (m, 4H, H-2′), 1.59 (m, 4H, H-3′), 1.79 (s, 2H, OH), 2.50 (m, 2H, H-2), 2.70 (m, 2H, H-3), 3.24 (m, 4H, H-1′), 3.39 (m, 2H, H-5), 3.72 (m, 10H, H-6, H-8, H-9, H-11, H-12), 3.9 (m, 2H, H-14), 4.22 (m, 2H, H-16), 4.58 (m, 1H, H-15), 7.14 (6H, H thiourea).
13 C RMN (CDCl 3 ): δ (ppm) 14.06 (C-14′), 22.67 (C-13′), 25.32 (C-3′), 27.80 (C-2), 28.56 (C-2′), 28.84 (C-3), 29.66 (C4′-C-11′), 31.25 (C-17), 31.92 (C-12′), 3.78 (C-5), 43.66 (C-6, C-8, C-9, C-11), 44.53 (C-14), 46.73 et 47.13(C-1′), 63.54 (C-16), 70.97 (C-15), 109.05 (C-17), 172.21 (C-1), 174.14 (C-4), 183.32 (C-7, C-10, C-13, C-16).
Example 5
Compaction of the Nucleic Acid in the Presence of DT-3TU (12)
The aim of this example is to illustrate the capacity of the transfecting compounds according to the invention to combine with the nucleic acids.
This can be easily demonstrated by a fluorescence test with ethidium bromide: the absence of fluorescence indicates the absence of free nucleic acid, which means that the nucleic acid was compacted by the transfecting compound.
The nucleic acid was brought into contact with increasing quantities of DT-3TU (12), by equivolumetric mixing of lipid solutions of various titers in the solutions of nucleic acid. Samples of 800 μl of nucleic acid complexes with a concentration of 0.01 μg/ml were thus prepared in a 150 mM sodium chloride solution with increasing quantities of DT-3TU (12).
In the same manner, a control was prepared by bringing the nucleic acid into contact with increasing quantities of EPC (see FIG. 1) or of DPPC (see FIG. 2 ), by equivolumetric mixing of lipid solutions of various titers in the solutions of nucleic acid. Samples of 800 μl of nucleic acid complexes with a concentration of 0.01 μg/mm were thus prepared in a 150 mM sodium chloride solution with increasing quantities of EPC or of DPPC (FIGS. 1 and 2 respectively).
The ethidium bromide fluorescence was measured over time (measured at 20° C.) using a FluoroMax-2 (Jobin Yvon-Spex) with excitation and emission wavelengths of 260 nm and 590 nm respectively. The slit widths for excitation and emission were set at 5 nm. The fluorescence value was recorded after addition of 3 μl of ethidium bromide to 1 g/l per ml of DNA/lipid solution (at 0.01 mg of DNA/ml).
The results were summarized in FIGS. 1 and 2.
In FIG. 1, the curve with squares shows that the addition of an increasing quantity of DT-3TU/EPC lipid mixture (0.75 to 20 nmol of DT-3TU) relative to a fixed quantity of nucleic acid (8 μg) induces a reduction in fluorescence linked to the reduction in the insertion of ethidium bromide between the base pairs of the DNA. This indicates that the combination between the DT-3TU/EPC liposomes and the DNA was sufficiently strong to exclude the ethidium bromide from the complexes. We were thus able to obtain up to 90% exclusion of fluorescence, that was 90% DNA-DT-3TU/EPC lipid combination. To show the active role of the DT-3TU lipid in this lipid/DNA combination, a control was prepared. It consists in observing the interaction between the EPC lipid and the DNA, this is represented by the curve with the diamonds. When the EPC was brought into contact with the DNA under conditions identical to those used for the study of the DT-3TU/EPC-DNA complexes, only a weak decrease in fluorescence was observed (about 5%), which may be attributed to the increase in the turbidity of the mixture. This control therefore reflects the absence of combination of EPC alone with the DNA under the abovementioned experimental conditions.
This example thus illustrates the capacity of the DT-3TU lipid to combine with the nucleic acid.
In the same manner, in FIG. 2, the curve with squares shows that the addition of an increasing quantity of DT-3TU/DPPC lipid mixture (0.75 to 20 nmol of DTTU) relative to a fixed quantity of nucleic acid (8 μg) induces a reduction in fluorescence when an identical quantity of ethidium bromide was added to the various samples. This indicates that the combination between the DT-3TU/DPPC liposomes and the DNA was sufficiently strong to exclude the ethidium bromide from the complexes. We were thus able to obtain up to 90% exclusion of fluorescence, that was 90% DNA-DTTU/DPPC combination. To show the active role of the DTTU lipid in this lipid/DNA combination, a control was prepared. It consists in observing the interaction between the DPPC lipid and the DNA, this is represented by the curve with the diamonds. When the DPPC was brought into contact with the DNA under conditions identical to those used for the study of the DT-3TU/DPPC-DNA complexes, only a weak decrease in fluorescence was observed (about 5%). This control therefore reflects the absence of the combination of DPPC alone with DNA under the abovementioned experimental conditions.
This example thus illustrates the capacity of the DT3-TU lipid to combine with the nucleic acid.
Example 6
Compaction of the DNA by DT-3TU/EPC Complexes
The aim of this example is to illustrate the capacity of the transfecting compounds according to the invention to compact the nucleic acids.
This may be easily demonstrated by a test of electrophoretic retardation on agarose gel of the DNA visualized by the use of ethidium bromide (EtBr): the absence of migration of the nucleic acid on the gel indicates the compaction of the nucleic acid. The free nucleic acid, for its part, was not subject to gel retardation.
Various DNA/DT-3TU samples comprising increasing quantities of DTTU lipid relative to the DNA were deposited on an agarose gel (0.8% agarose in 1N TBE). The gel was subjected to an electric current for one and a half hours at 70 V and 70 mA in order to cause the DNA to migrate by electrophoresis. The bands were revealed with EtBr and by absorption under a UV lamp. The results were represented in FIG. 3 .
The gel shows the electrophoretic migration of the DNA when it was not combined with the lipids (well 1), and then its difference in retention when it was combined with the lipids. Wells 2 to 6 represent the DNA (0.01 g/l) combined with increasing quantities of DTTU/EPC liposomes: 0.75 then 5 then 10 then 15 and finally 20 nmol of DTTU lipid. Comparison between well 1 and the other wells indicates that the higher the increase in the quantity of DT-3TU lipid, the more DNA was retained on the gel which was completely retarded from 3 nmol of DTTU/μg of DNA, zone of aggregation of the complexes. Wells 8 to 13 correspond respectively to the DNA alone (0.1 g/l, 1 μg for the gel), the lipoplexes formed at the concentration of 0.1 g/l of DNA at the lipid/DNA ratios: 0.75 or 5 or 10 or 15 and finally 20 nmol/μg of DNA. In the same manner, it can be observed that at this concentration of DNA compatible with in vivo experiments, the DNA was compacted from ratios of 5 nmol lipid/μg of DNA.
This example thus illustrates the capacity of the DT-3TU lipid to compact the nucleic acid.
Example 7
Measurement of the Zeta Potential of the DT-3TU/DNA Compositions
The aim of this example is to illustrate the capacity of the transfecting compounds according to the invention to compact the nucleic acids while preserving a globally anionic, neutral or very weakly cationic structure.
This may be demonstrated by a measurement of the Zeta potential; the measurement given in mV indicates the surface charge of the particle relative to the electrophoretic mobility of the sample.
The nucleic acid was brought into contact with increasing quantities of the DT-3TU/EPC lipid mixture by equivolumetric mixing of lipid solutions of various titers in the solutions of nucleic acid. Samples of 2 ml of nucleic acid complexes with a concentration of 0.01 g/l were thus prepared in a 20 mM sodium chloride solution with increasing quantities of DT-3TU.
The measurement of the Zeta potential (mV) was carried out using a zetasizer 3000 Hsa (Malvern). The value of the potential was determined 3 times in succession on 2 ml of DT-3TU/EPC-DNA sample. The results were summarized in FIG. 4 .
The DTTU/EPC liposomes were added to the DNA in a zone ranging from 0.75 nmol to 20 nmol of lipids per μg of DNA. In this zone of variation of the quantity of lipid, the Zeta potential varies from −35 mV to +15 mV. The negative part corresponds to what is shown in FIGS. 1, 2 and 3 , namely that the Zeta potential was negative when the DNA was not completely compacted. The more lipid added, the more the DNA was compacted and the more the Zeta potential approaches zero, the lipoplexes then exhibit a practically zero surface potential. The Zeta potential then becomes slightly positive toward 8 nmol of lipid/μg of DNA. The relativity of this measurement should take into account the comparison of the various samples during the same experiment. It is thus important to note the evolution of the Zeta potential as a function of the increase in the quantity of lipid up to a weakly positive value.
This example thus confirms the compaction of the DNA by the transfecting compounds according to the invention, in particular DT-3TU, and show that the lipoplexes formed exhibit a surface potential close to neutrality.
Example 8
In vitro Transfection of the DT-3TU/DNA Compositions
The aim of this example is to illustrate the capacity of the transfecting compounds according to the invention to transfect cells in vitro.
This study was carried out for lipoplexes comprising various quantities of DT-3TU: 1.5 or 5 or 10 or 15 or 20 nmol of DT-3TU/μg of DNA. Each of these conditions was tested with and without fetal calf serum (“+Serum” or “−Serum”).
The cell culture:
HeLa cells (American type Culture Collection (ATCC) Rockville, Md., USA) derived from a carcinoma of human cervical epithelium, were cultured in the presence of an MEM (“minimum essential medium”) type medium with addition of 2 mM L-glutamine, 50 units/ml of penicillin and 50 units/ml of streptomycin. The medium and the additives were from Gibco-BRL Life Technologies (Gaithersburg, Md., USA). The cells were cultured in flasks at 37° C. and at 5% carbon dioxide in an incubator.
Transfection:
one day before the transfection, the HeLa cells were transferred into 240-well plates with a cell number of 30,000 to 50,000 per well. These dilutions represent approximately 80% confluence after 24 hours. For the transfection, the cells were washed twice and incubated at 37° C. with 500 μl of medium with serum (10% FCS v/v) or without serum. 50 μl of complexes containing 0.5 μg of plasmid DNA were added to each well (the complexes were prepared at least 30 minutes before addition to the wells). After 2 hours at 37° C., the plates without serum were supplemented with 10% (v/v) FCS (“Fetal Calf Serum”).
All the plates were placed for 24 hours at 37° C. and at 5% carbon dioxide.
Determination of luciferase activity:
Briefly, the transfected cells were washed twice with 500 μl of PBS (phosphate buffer) and then lysed with 250 μl of reagent (Promega cell culture lysis reagent, of the Luciferase Assay System kit). An aliquot of 10 μl of supernatant of the lysate centrifuged (12,000×g) for 5 minutes at 4° C. was measured with a Wallace Victor 2 luminometer (1420 Multilabel couter). The luciferase activity was assayed by the light emission in the presence of luciferin, coenzyme A and ATP for 10 seconds and expressed relative to 2000 treated cells. The luciferase activity was then expressed in relative light units (RLU) and normalized with the concentration of proteins in the sample obtained using a Pierce BCA kit (Rockford, Ill., USA).
The results summarized in FIG. 5 show an optimum transfection efficiency for the lipoplexes comprising 5 or 10 nmol of DT-3TU per μg of DNA. The presence of serum induces a weak inhibition of transfection in all cases.
Example 9
Determination of the Toxicity of the DTTU/DNA Lipoplexes Toward the Cells
The aim of this example is to illustrate the absence of toxicity of the transfecting compounds according to the invention.
The protein level was measured after transfection. The transfection protocol was identical to that described in Example 8.
Determination of the protein level:
Briefly, the transfected cells were washed twice with 500 μl of PBS (phosphate buffer) and then lysed with 250 μl of reagent (Promega cell culture lysis reagent, of the Luciferase Assay System kit). An aliquot of 50 μl of supernatant of the lysate centrifuged (12,000×g) for 5 minutes at 4° C. was transferred into a tube in the presence of 50 μl of 0.1 M iodoacetamide, 0.1 M hydrochloric acid tris at pH 8.2 and left for 1 hour at 37° C. 20 μl of the preceding solutions were deposited in a 96-well plate and 200 μl of “BCA protein assay” reagent (Pierce, Montluson, France) were added. The plate was then centrifuged at 2500 revolutions/min and then incubated at 37° C. for 30 minutes. In parallel, a bovine serum albumin (BSA) range was prepared in order to correlate the absorbance value obtained for the samples with a quantity of protein present in the sample.
The results summarized in FIG. 6 show a similar protein level regardless of the condition used, the lipoplexes comprising 0.75 or 5 or 10 or 15 or 20 nmol of DT-3TU per μg of DNA. The presence of DTTU lipid does not therefore adversely affect the cell and no toxicity was observed under the conditions used.
This example therefore illustrates one of the major advantages of the transfecting compounds according to the invention, namely their very low toxicity probably linked to the absence of positive charges in their structure.
Example 10
Compaction of the Nucleic Acid by DT-3TU/DPPC Nanoemulsions
The aim of this example is to illustrate the capacity of the transfecting compounds according to the invention to combine with the nucleic acids.
This may be easily demonstrated by a test of electrophoretic retardation on agarose gel of the DNA visualised by the use of ethidium bromide (EtBr): the absence of migration of the nucleic acid on the gel indicates the compaction of the nucleic acid. The free nucleic acid, for its part, is not subject to gel retardation.
Various DNA/DT-3TU samples comprising different formulations of DT-3TU lipid relative to the DNA were placed on an agarose gel (0.8% agarose in 1 N TBE). The gel is subjected to an electric current for one and a halt hours at 70V and 40 mA in order to cause the DNA to migrate by electrophoresis. The bands were revealed with TBE and by absorption under a UV lamp. The results were presented in FIG. 8 .
In the same way, the capacity of the DT-3TU diol compound to compact the DNA is shown by using an agarose gel (0.8% agarose in 1 N TBE), on which different samples of DNA/DT-3TU diol comprising different formulations of DT-3TUdiol lipid relative to the DNA were placed. The gel is subjected to an electric current for one and a half hours at 70V and 40 mA in order to cause the DNA to migrate by electrophoresis. The bands were revealed with ethidium bromide and by absorption under a UV lamp.
The gel shows the electrophoretic migration of the DNA when it is not combined with the lipids (well 1), and then its difference in retention when it is combined with the lipids. Wells 2 to 5 represent the DNA (0.01 g/l) combined with DT-3TU/DPPC (60 nmol DT-3TU/μg of DNA) nanoemulsions containing or not calcium and ethanol. Well 2 represents 60 nmol/μg of DNA without Ca 2+ and ethanol. In well 3, 2% of EtOH was added. In well 4, 60 eq. of Ca 2+ /PO − DNA. In well 5, 2% of EtOH and 60 eq. of Ca 2+ . Comparison between well 1 and the other wells indicates that the different DT-3TU formulations that were studied retard the DNA migration on the gel. The same result was observed after dialysis of Ca 2+ and EtOH.
This example illustrates thus the capacity of the DT-3TU lipid incorporated in different formulations to compact the nucleic acid.
Example 11
Compaction of the Nucleic Acid by Stabilised DT-3TU/DPPC Complexes
The aim of this example is to illustrate the capacity of the transfecting compounds according to the invention to combine with the nucleic acids.
This may be easily demonstrated by a test of electrophoretic retardation on agarose gel of the DNA visualised by the use of ethidium bromide (EtBr): the absence of migration of the nucleic acid on the gel indicates the compaction of the nucleic acid. The free nucleic acid, for its part, is not subject to gel retardation.
Various DNA/DT-3TU/DPPC and DNA/DT-3TUdiol/DPPC samples comprising increasing quantities of DT-3TU lipid relative to the DNA combined or not to the cholesterol-PEG were placed on an agarose gel (0.8% agarose in 1 N TBE). The gel was subjected to an electric current for one and a half hours at 70V and 40 mA in order to cause the DNA to migrate by electrophoresis. The bands were revealed with ethidium bromide and by absorption under a UV lamp. The results are shown in FIG. 9 .
The use of cholesterol-PEG in the DT-3TU/DPPC formulations has the advantage of permitting the reduction of the particles to such a quantity of lipid that, in the case of the absence of lipid-PEG, would lead to aggregation. The interest in this result is to optimise the quantities of the transfecting compounds injected in vivo. In fact, the required size of the particles to have furtive objects towards the serum proteins should be manly inferior to 500 nm in order to have their half-life time increased in the blood stream. In order to obtain particles of this size it is necessary to use at least 40 nmol of the lipid DT-3TU/μg of DNA. Thus, the use of lipid-PEG in the formulations of the lipid DT-3TU has the advantage of reducing the quantity of DT-3TU necessary to compact the DNA and form particles whose size is smaller than 500 nm
The gel shows the electrophoretic migration of the DNA when it is not combined with the lipids (well 1), and then its difference in retention when it is combined with the lipids. Wells 2 to 5 represent the DNA (0.01 g/l) combined with increased quantities of DT-3TU/DPPC nanoemulsions containing or not cholesterol-PEG (20 unites of ethylene glycol) as stabilising agent for the particles. Well 2 A represent 20 nmol/μg of DNA+15% of cholesterol-PEG. Well 3 contains 20 nmol/μg of DNA+20% of cholesterol-PEG. Well 4 represents 30 nmol/μg of DNA+15% of cholesterol-PEG and well 5 represents 20 nmol/μg of DNA+20% of cholesterol-PEG. Comparison between well 1 and the other wells indicates that the different DT-3TU formulations studied retard the DNA migration on the gel, showing the possibility of incorporating polymers of polyethylene glycol in these formulations without breaking free the DNA from the complexes and thus, without destabilising them.
This example illustrates thus the capacity of the DT-3TU lipid in the form of stabilised particles to compact the nucleic acid.
Example 12
Compaction of the Nucleic Acid in the Presence of DT-4TU (15)
The aim of this example is to illustrate the capacity of the transfecting compounds according to the invention to combine With the nucleic acids.
This can be easily demonstrated by a fluorescence test with ethidium bromide: the absence of fluorescence indicates the absence of free nucleic acid, which means that the nucleic acid was compacted by the transfecting compound.
The nucleic acid was brought into contact with increasing quantities of DT-4TU, by equivolumetric mixing of lipid solutions of various titers in the solutions of nucleic acid. Samples of 800 μl of nucleic acid complexes with a concentration of 0.01 μg/ml are thus prepared in a 150 mM solution of sodium chloride with increasing quantities of DT-4TU (15).
In the same manner, a control was prepared by bringing the nucleic acid into contact with increasing quantities of DT-3TU (12) by equivolumetric mixing of lipid solutions of different titers in the solutions of nucleic acid, to compare the efficiency of the complexion of a lipid containing 3 thioureas (see FIG. 2) with a lipid containing 4 thioureas. Samples of 800 μl of nucleic acid complexes with a concentration of 0.01 μg/ml are thus prepared in a solution of 5% glucose with increasing quantities of DPPC.
The ethidium bromide fluorescence was measured using a FluoroMax-2 (Jobin Yvon-Spex) with excitation and emission wavelengths of 260 nm and 590 nm respectively. The slit widths for excitation and emission are set at 5 nm. The fluorescence value was recorded after addition of 3 μl of ethidium bromide (1 g/l) per ml of DNA/lipid solution (0.01 g/l of DNA). The results are summarised in FIG. 10 .
The curve with squares shows that the addition of an increasing quantity of DT-3TU/DPPC lipid mixture (0.75 to 30 nmoles of DT-3TU) relative to a fixed quantity of nucleic acid (8 μg) induces a reduction in fluorescence linked to the reduction of insertion of ethidium bromide between the base pairs of the DNA. This indicates that the combination between the liposomes DT-3TU/DPPC and the DNA was sufficiently strong to exclude the ethidium bromide from the complexes. We were thus able to obta 0 in 70% of the DNA compaction using 30 nmol of DT-3TU/DPPC lipids per μg of DNA. The active role of the DT-3TU in this lipids/DNA combination is shown in FIGS. 1 and 2. In the same manner, increasing quantities of DT4-TU/DPPC lipid mixture (0.75 to 30 nmoles of DT-3TU) were added to a fixed quantity of nucleic acid (8 μg). This combination induces a reduction in fluorescence linked to the reduction of insertion of ethidium bromide between the base pairs of the DNA. This indicates that the combination between the liposomes DT-4TU/DPPC and the DNA was sufficiently strong to exclude the ethidium bromide from the complexes. We were thus able to obtain 60% of the DNA compaction for 30 nmoles of lipid per μg of DNA (FIG. 10, curve with circles), which was similar to the efficiency of the DT-3TU complexion using the same conditions.
This example illustrates thus the capacity of the DT-4TU lipid to combine with the nucleic acid.
Example 13
Protection of the DNA from the DNAses by DT-3TU/DPPC Complexes
The aim of this example is to illustrate the capacity of the transfecting compounds according to the invention to protect the nucleic acids from enzymatic hydrolysis, namely the DNAses.
This may be easily demonstrated by a test of electrophoretic retardation on agarose gel of the DNA visualised by the use of ethidium bromide (EtBr). The free DNA or the DNA complexed with the lipid was treated with the right quantity of DNAse. The DNA was extracted from the enzymatic digestion mixture and was placed on an agarose gel. Its integrity was verified by comparison of its migration with that of the nucleic acid that had not been treated.
Various DNA samples, previously treated with 2.10 −4 M of DNAse (Sigma), were placed on an agarose gel (0.8% agarose in 1 N TBE). Treatment with the DNAse was carried out on the free DNA and on the DNA complexed with increasing quantities of the DT-3TU lipid when compared with the DNA. The gel was subjected to an electric current for one and a half hours at 70V and 40 mA in order to cause the DNA to migrate by electrophoresis. The bands were revealed with ethidium bromide and by absorption under a UV lamp. The results are shown in FIG. 11 .
The gel shows the electrophoretic migration of the DNA when it was not treated with the DNAse (well 1), and then its difference in retention after treatment. Well 2 represents the same quantity of DNA (3 μg) when treated with 2.10 −4 M of DNAse. Following this treatment (2.10 −4 M of DNAse, 30 min. 37° C.), the corresponding band was not revealed, which indicates a degradation of the DNA. The nucleic acid complexed with 30 and 40 nmol of DT-3TU lipid per μg of DNA and with 40 nmol of DT-3TU lipid+6% of Chol-PEG was treated with 2.10 −4 M of DNAse. After extraction of the DNA using a mixture of phenol/chloroform and its precipitation, the nucleic acid was placed on the agarose gel, respectively in wells 3, 4, and 5. The migration of the DNA was similar to the migration of the DNA that had not been treated previously with the DNAse. This indicates that the DNA was intact, that it has not been damaged by the treatment with DNAse and thus the DT-3TU lipid has protected it. The DNA in the DT-3TU lipid complexes was thus not accessible to the enzymatic hydrolysis, the nucleic acid was protected from the hydrolysis of the DNAses.
This example illustrates thus the capacity of the DT-3TU lipid to protect the nucleic acid from the enzymatic hydrolysis.
Example 14
Protection of the DNA from the Serum by the DT-3TU/DPPC Complexes
The aim of this example is to illustrate the capacity of the transfecting compounds according to the invention to protect the nucleic acids from degradation in the serum.
This may be easily demonstrated by a test of electrophoretic retardation on agarose gel of the DNA visualised by the use of ethidium bromide (EtBr). The free DNA or the DNA complexed with the lipid was incubated with different quantities of serum at 37° C. After its extraction from the serum, the DNA was placed on an agarose gel and its integrity was verified by comparison of its migration with that of the nucleic acid that had not been incubated.
Various DNA samples, previously incubated in 150 mM of NaCl, 20% and 100% of serum, were placed on an agarose gel (0.8% agarose in 1 N TBE). The saline and serum treatments were carried out with the free DNA and with the complexed DNA with increasing quantities of DT-3TU when compared with the DNA. The gel was subjected to an electric current for one and a half hours at 70V and 40 mA in order to cause the DNA to migrate by electrophoresis. The bands were revealed with ethidium bromide and by absorption under a UV lamp. The results are shown in FIG. 12 .
The gel shows the electrophoretic migration of the DNA that was not treated (the blank) (well 1), then its difference in retention when the free DNA was treated in a saline solution (150 mM of NaCl) (well 2), when the DNA was complexed with 40 nmol of DT-3TU lipid per μg of DNA (well 3). The migration of the DNA extracted from the saline solution was similar in both wells. This indicates that the DNA was kept intact under these conditions. The following wells show in the same order the DNA (wells 4 and 6), the DNA+40 nmol of DT-3TU lipid (wells 5 and 7)in two different serum conditions: 20% of serum for the case of wells 4 to 5 and 100% of serum for the wells 6 to 7. When the DNA was free, the nucleic acid was completely degraded after 30 minutes at 37° C. (wells 4 and 6) under both the serum conditions mentioned previously. On the other hand, the DNA complexion with DT-3TU/DPPC nanoemulsions induces the protection of the nucleic acid since the migration band corresponding to the DNA was revealed (wells 5 and 7). The DNA in the DT-3TU lipid complexes was thus protected in the serum from degradation when compared with the free DNA.
This example illustrates thus the capacity of the DT-3TU lipid to protect the nucleic acid from degradation in the serum.
Example 15
In vivo Transfection of the DT-3TU/DNA Compositions
The aim of this example is to illustrate the capacity of the transfecting compounds according to the invention to transfect biological tissues in vivo.
This may be demonstrated by the intramuscular injection of the coding DNA complexes for the luciferase. Muscles samples were taken 96 hours after the injection and the level of expression for luciferase was measured using a luminometer (wallace).
Complexes containing increasing quantities of DT-3TU lipid per μg of DNA were injected in both tibial and cranial muscles of the mice, to which electric pulsations were or were not applied (Bureau, M et al, BBA 2000).
Complexes with increasing quantities of 40 and 60 mmol of DT-3TU lipid per μg of DNA were injected in a volume of 30 μL containing 3 μg of DNA per animal in both tibial and cranial muscles. The mice C57bl/6 had undergone previously anaesthetic with a mixture of Ketamin/Xylazine. The injection was or was not followed by the application of transcutaneous electric pulsations using electrodes placed in both ends of the muscle (Bureau, M et al, BBA 2000).
96 hours after the injection, the mice underwent euthanasia, muscles samples were taken and ground in 1 ml buffer lyse solution. After centrifugation (10 min., 12000 rpm, 4° C.), supernatant (10 μl) was taken and placed in a 96 well plate to read the luciferase after adding 50 μl of luciferase substrate. The level of luminescence was read in the supernatant using a luminometer (Wallace, Victor).
The results obtained are shown in FIG. 13 . They represent the level of expression relative to the quantity of lipid combined with the nucleic acid, 20 and 40 nmol of DT-3TU lipid per μg of DNA. The different levels of expression that were obtained were significant and they were superior to the background noise that was obtained when the muscle was taken as a control (5.0×10 4 ). The DNA complexed with different quantities of DT-3TU lipid was thus able to transfect the muscle tissues with a significant level of transfection.
This example illustrates the capacity of the transfecting compounds according to the invention to transfect tissues in vivo.
Example 16
In vivo Biodistribution of the DT-3TU/DPPC/DNA Complexes
The aim of this example is to illustrate the capacity of the transfecting compounds according to the invention to stay longer periods of time in the bloodstream in vivo due to their neutral character.
This may be demonstrated by the injection of the DNA complexes containing a fluorescent lipid in the mouse bloodstream. Blood samples were then taken at different times after the injection and the level of fluorescence in the bloodstream was measured using a FluoroMax-2 (Jobin Yvon-Spex).
Complexes containing 40 nmol of DT-3TU lipid per μg of DNA, 1 molar equivalent of DPPC/DT-3TU lipid and 0.7% of lipid-rhodamine (of the total amount of lipids) were injected in a volume of 200 μl containing 11 μg of DNA per animal in the caudal vein. The mice C57bl/6 had undergone anaesthetic with a mixture of Ketamin/Xylazine.
After the injection, blood samples were taken at 30 minutes, 1 hour and 6 hours by intracardiac puncture while the mice were anaesthetic. After euthanasia of the mice, the liver, the spleen and lungs were immediately extracted, weighed and homogenised in PBS (5 μl per mg of tissue). The lipids were extracted from 100 μL of blood and homogenised organs using 3 ml of chloroform/methanol mixture (1/1), by vigorously stirring for 30 minutes and then by centrifuge. The fluorescence in the supernatant was measured using a FluoroMax-2 (Jobin Yvon-Spex), with excitation and emission wavelengths of 550 nm and 590 nm respectively. The slit widths for excitation and emission were set at 5 nm.
The results are summarised in FIG. 14 . They represent the percentage of the dose injected obtained from the blood, lungs and the reticulo endothelial system (liver and spleen together) 30 minutes, 1 hour and 6 hours after injection. The measure of the fluorescence in the blood after 30 minutes represent 50% of the dose injected, which was much superior to what can be obtained with the DNA surfactant of the cationic type. After 1 hour, 17% of the dose injected could be detected, which still represents a remarkable improvement when compared with cationic complexes. The neutral character of these lipid/DNA complexes (zeta potential was very weakly positive: FIG. 4) represents thus a real advantage to obtain furtive particles towards the serum proteins. The neutral character should also restrict their interactions with the macrophages and the kupffer cells of the liver and spleen and this might explain the quantity of liposome found in the blood 30 minutes and 1 hour after the injection.
The quantity of lipoplexe found in the lungs was low compared with the quantity found when cationic lipoplexes were used. The neutrality of the liposomes should also decrease the non-specific interactions with the negative endothelium of the lungs.
This example illustrates the capacity of the transfecting compounds according to the invention to be furtive towards serum proteins. | The present invention relates to novel compounds which make it possible to transfer nucleic acids into cells. These novel compounds are lipid derivatives of polythiourea. They are useful for the in vitro, ex vivo or in vivo transfection of nucleic acids into various cell types. | 0 |
This is a continuation of application Ser. No. 87,337, filed Oct. 23, 1979, now abandoned.
DESCRIPTION
This invention relates to sealing articles and their use in the insulation and protection of substrates such as supply lines.
Heat-recoverable articles, especially heat-shrinkable articles, are now widely used in many areas where insulation, sealing and encapsulation are required. Usually these articles recover, on heating, towards an original shape from which they have previously been deformed, but the term "heat-recoverable", as used herein, also includes an article which, on heating, adopts a new configuration, even if it has not been previously deformed.
In their most common form, such articles comprise a heat-shrinkable sleeve made from a polymeric material exhibiting the property of elastic or plastic memory as described, for example, in U.S. Pat. Nos. 2,027,962; 3,086,242 and 3,957,372. As is made clear in, for example, U.S. Pat. No. 2,027,962, the original dimensionally heat-stable form may be a transient form in a continuous process in which, for example, an extruded tube is expanded, whilst hot, to a dimensionally heat-unstable form but, in other applications, a preformed dimensionally heat-stable article is deformed to a dimensionally heat unstable form in a separate stage.
In other articles, as described, for example, in British Pat. No. 1,440,524, an elastomeric member such as an outer tubular member is held in a stretched state by a second member, such as an inner tubular member, which, upon heating, weakens and thus allows the elastomeric member to recover.
Heat-shrinkable sleeves find many applications, especially in the connection and termination of wires, cables and pipes. However, there are other applications where it is desirable to provide a connecting, insulating or protective heat-recoverable member for elongate objects such as cables and pipes where the ends are not accessible or, if they are accessible, where it is undesirable to disconnect or otherwise displace them. For such applications so-called "wrap-around" sleeves have been developed. Basically these are heat-recoverable sheets which can be wrapped round the substrate to form a generally tubular shape and which, in general, are provided with fastening means for holding them in the wrapped-up configuration during recovery. Typically such fastening means are mechanical in nature and comprise, for example, rigid clamps, pins or channel members which co-operate with suitably shaped moulded or extruded protuberances adjacent to the overlapping edges of the heat-recoverable sheet. Various types of fastening means are described, for example, in U.S. Pat. No. 3,379,218 and British Pat. Nos. 1,155,470; 1,211,988 and 1,346,479. In other applications, however, the sheet may be held in the wrapped-up configuration during recovery by means of an adhesive which may, in some cases, be applied on site.
Heat-recoverable sleeves and wrap-around sleeve have been successfully employed in many fields of application. One particularly important field in which they are employed is in the protection of communication system cables. Such cables must periodically be spliced to connect successive portions and to provide access for branch cables and terminals. At the splices so effected the protected sheaths must be disturbed thus providing an opportunity for moisture and other contaminants to reach and damage or destroy the unprotected conductors and the splice. For this reason splice cases have been developed to protect and seal the splice and the cable ends. Especially useful splice cases and materials and components for use therein are described, for example, in German OS Nos. 2,543,338, 2,543,314, 2,543,346, 2,635,000 and 2,539,275. Another important type of splice case is described and claimed in U.S. Pat. No. 4,142,592, the disclosure of which is incorporated herein by reference.
The splice cases mentioned above have proved extremely successful in practice in many types of cables including, especially, pressurised cables, i.e. those in which a small pressure of, for example, up to about 2 kg/cm 2 , typically about 0.5 kg/cm 2 , is maintained in order to prevent the ingress of water through a damaged cable jacket. The application of splice cases to such pressurised cables is discussed in the Patents mentioned above and also in U.S. Pat. No. 4,268,329, the disclosure of which is incorporated herein by reference, and in German OS No. 2,638,448.
Such splice cases are provided with outer heat-recoverable sleeves which are shrunk down over the splice when the latter has been completed. It will be appreciated that the ends of the heat-shrinkable sleeve, which may be a wrap-around sleeve, are shrunk down firmly over the cables forming the splice and, for this purpose, they are generally provided with a heat activatable adhesive to provide a good seal to the cables. However, the presence of the splice case itself precludes the central portion of the heat-recoverable sleeve from complete recovery and, therefore, in a pressurized cable the pressure within the splice case tends to force the heat-recoverable sleeve away from the cables and, in particular, puts the adhesive layer in the region at which the heat-recoverable sleeve first contacts the cable under considerable strain, rendering it liable to failure by peel. A further complication is that the counteracting recovery force of the heat-recoverable sleeve tends to relax with time down to some limit value. Failure can, in general, be avoided by, for example, ensuring that a sufficient length of heat-recoverable sleeve is shrunk down on each cable and by other measures such as solvent cleaning of the cable jackets, abrasion of the jacket surfaces and flame brushing and, at the relatively low pressures employed to date the splices have readily met the test requirements of the users. However, at slightly higher pressures, which are now proposed for use in pressurised cables, the problem becomes more severe, especially bearing in mind that the expected life time of the joints is from 20 to 30 years and in view of the fact that, in practice, cable preparation is dependent upon the skill of the operator. It will, in any case, be appreciated that similar problems may arise in other applications in which external or internal forces may tend to cause the sleeve to come out of contact with the substrate.
The present invention provides a method of recovering a heat-recoverable article on or about a substrate, wherein there is interposed between the article and the substrate at least one flexible auxiliary member which is adapted to eliminate or to reduce the effect of a force tending to cause the heat-recoverable article to be brought out of contact with said substrate.
By "flexible" we mean able to be deformed by a force which will, in the absence of the member, lead to the article being brought out of contact with the substrate. In general, therefore, the article will be deformed to enhance the contact of its surfaces with the member and the substrate. Accordingly, while the member is to be responsive to such forces it should not itself be rupturable or caused to flow thereby at least when interposed between the article and the substrate.
As will be appreciated that the following discussion, the invention is generally applicable to any use of heat-recoverable articles including, for example, those in which the article is a heat-expansible article which is adapted to contact the inner surface of a utility line such as a duct. Reference is made in this respect to British Patent No. 1,245,119. Reference is also made to U.S. Pat. Nos. 4,194,750 and 4,268,041, the disclosures of which are also incorporated herein by reference. It will also be appreciated that the concept of the present invention may be applicable to situations in which no heat-recoverable article is used but in which, nonetheless, forces derived from internal pressure or some other cause tend to put an interface in danger of failure by peel.
However, for convenience, the invention will now be described in more detail with reference to the use of heat-shrinkable sleeves in the protection of splices in pressurised cables.
Accordingly, the essence of one aspect of the present invention is to provide one or more auxiliary members which isolate the interface region from the forces which would otherwise tend to cause peel at the interface and which, preferably, do so by themselves accommodating those forces. In one embodiment of the present invention the auxiliary member presents to such forces a re-entrant or concave surface, and preferably the member comprises a strip of generally U- or V-shaped cross-section, the base of which lies at or adjacent the interface between the heat-shrinkable sleeve and the cable and the arms of which are attached, e.g. by adhesive, to the heat-shrinkable sleeve and the cable jacket, respectively, in the direction of the splice. The strip is preferably flexible at least insofar that it is able to respond to pressure by opening out, so as to enlarge the U or V. Thus the strip may, for example, be made from a flexible polymeric material, cross-linked polyethylene being especially preferred or may, in some applications, be hinged at its base, this being achieved for example by the provision of a relatively flexible region at the base of an otherwise relatively rigid strip. If desired the strip may be reinforced along its length so as to provide it with some structural strength and, in certain applications it may be desirable to provide it with further reinforcement at spaced apart regions along its length.
The strip may be provided as a continuous length which is cut to size and wrapped around the circumference of the cable or may be provided as standard size lengths for this purpose; for large diameter cables it may be appropriate to use two or more of such standard size lengths. In other embodiments it may be appropriate to provide the U- or V-shaped strip as a continuous annular member which is positioned around the cable. The strip may, for example, be moulded or extruded. In all cases the strip can, if desired, itself be heat-recoverable so that it can be caused to recover and firmly grip the cable. The material of the strip should preferably be non-meltable below about 180° C. and should be capable of adhering to the hot melt or other adhesives commonly employed in splicing. It should also be sufficiently thick that it does not tear or crack under the strains and pressures involved. Cross-linked flat polyethylene sheet having a thickness of 0.3 to 0.5 mm is particularly suitable.
In those applications where the strip is to be wrapped around the cable it will be necessary for the ends to overlap and the length of the strip is, therefore, preferably, from 1.25 to 1.75 times that of the circumference of the cable jacket. In order properly to secure the overlapping ends of the strip to each other, the side walls of each end of the strip are preferably bonded together, for example, by peroxide so as to provide flat end portions which are themselves bonded to each other in the overlapping region. As mentioned above, in some cases, it may be desirable to use two lengths of strip in order to form an annular member about the circumference of the cable. Once again, the overlapping ends of the strips will preferably be flattened to facilitate bonding. In all embodiments it will be advantageous to mark the strips so as to indicate to the operator where the minimum region of overlap should occur. The strip may, for example, be provided with a coloured region where overlap is to occur. In some embodiments the strip may form part of the heat-recoverable sleeve itself, i.e. it may be an integral moulded part of the heat-recoverable sleeve or may be attached to the inner surface thereof prior to recovery. However, in presently preferred embodiments the strip is provided as a separate member which becomes attached to the inside of the heat-recoverable sleeve by adhesion with the hot melt or other adhesive provided on the inner surface thereof. The other side of the strip is itself preferably provided with an outer layer of the same or a similar adhesive for adhesion to the cable. In some cases it may be preferable to use a mastic which may give better wetting and sealing at low temperatures and allow less cable preparation.
It will be preferable to provide means for maintaining the strip in the desired position during recovery. In this respect it may be possible, as mentioned above, to provide a heat-recoverable strip which is initially shrunk onto the cable. In other embodiments the strip may itself be resilient, e.g. made from a natural or synthetic elastomer or may be provided with a resilient component such as a coil spring in order to grip the cable. However, the strip may advantageously be retained in position by providing a material coated with a contact adhesive which adheres to the side of the U- or V-shaped strip adjacent the cable and to the cable itself. Such a material may, for example, be a tape of thin foil provided on its upper surface with a release agent (in order to prevent the two sides of the U- or V-shaped strip from sticking together) and on its lower side with a contact adhesive.
In all embodiments of the present invention it will be preferred to provide some means to ensure that the sides of the U- or V-shaped strip do not stick together and, in this respect, it may be appropriate to provide a release foil as an insert between the said sides. It may also be desirable for the release foil to extend some distance, for example about 15 mm, from the edge of the strip towards the splice, in order to prevent the sleeve from sticking to the cable jacket between the strip and the splice.
It will be appreciated that the present invention may be used in many applications and, in particular, is not limited to applications in which the heat-recoverable article is a simple heat-shrinkable tubular sleeve. Thus it may, for example, be used where branch-off connections are being made, and in this respect, is suitable for use together with the clips and fork members described and claimed in U.S. Pat. Nos. 4,298,415 and 4,246,687, respectively, the disclosures of which are incorporated herein by reference.
Suitable materials and adhesives for use in the method of the present invention are described in the various Patents referred to herein and will, in any case, be known to those skilled in the art.
The present invention also provides auxiliary members, especially the above described U- or V-shaped strips, for use in the method of the present invention. For example, the invention provides a flexible auxiliary member for use in recovering a heat-recoverable article on or about a substrate, said member being adapted to be interposed between the article and the substrate and comprising a strip of generally U- or V-shaped cross-section coated on at least one exterior surface by an adhesive or a mastic.
In another aspect, the invention also provides a splice in a pressurised cable or a joint in a pressurised supply line protected by a sleeve provided with one or more flexible auxiliary members interposed between the sleeve and the cable or supply line and so positioned as to present a re-entrant or concave surface to the forces generated by the internal pressure of the cable or supply line such that the forces which would otherwise tend to cause peel at an interface between the sleeve and the cable or supply line are reduced or eliminated. The invention also provides a kit of parts comprising a sleeve and an auxiliary member as aforesaid for protecting a splice in a pressurised cable or a joint in a pressurised supply line.
Various embodiments in accordance with the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:
FIG. 1 is a longitudinal cross-section through one end of a conventional cable splice;
FIG. 2 is a longitudinal cross-section through one end of a protected cable splice;
FIG. 3 shows a V-strip as used in the arrangement shown in FIG. 2;
FIG. 4 is a cross-section along the line α--α of FIG. 3;
FIG. 5 shows the application of the V-strip of FIGS. 3 and 4 to a cable;
FIG. 6 is a transverse cross-section along the line β--β of FIG. 2;
FIG. 7 is a similar cross-section to that shown in FIG. 6;
FIG. 8 is a transverse cross-section taken through a break-out splice;
FIG. 9 shows an application for a tubular V-strip; and
FIG. 10 shows a further form of V-strip provided with a spring component.
Referring now to the drawings, in FIG. 1 there is shown an end portion of a protected splice made by a conventional method such as, for example, one of those described in the patents referred to above. As can be seen, the splice 1 (which is not shown in detail) is protected by a heat-recoverable sleeve 2 which is shrunk, at the end shown, about cable 3. The pressure within the cable indicated by the arrows tends to cause failure of the bond between the sleeve 2 and the cable 3, especially at interface 4. A hot melt adhesive 5 is typically provided on the inner surface of the sleeve 2 at least in those regions in which it contacts the cable 3.
In FIG. 2 there is shown an arrangement in accordance with the present invention in which a V-strip 6 made from cross-linked polyethylene is positioned between the sleeve 2 and the cable 3 so that the base thereof lies at or adjacent the interface 4.
As is shown more clearly in FIGS. 3 and 4 the V-strip 6 is provided on its lower side with a layer of hot melt adhesive or mastic 7 and on its upper side is contacted by the hot melt adhesive layer 5 provided on the inner surface of the sleeve 2. In order to secure the V-strip in position prior to recovery it is also provided on the upper surface of its lower side with a silicone foil tape 8 which is itself provided with a lower layer of contact adhesive 9. As is shown most clearly in FIG. 3 the ends of the V-strip 10 and 11 are closed, for example by bonding with a peroxide and, as is shown most clearly in FIG. 6 the overlapping ends are secured together so as to give a degree of overlap.
FIG. 5 shows the instalment of the V-strip 6 prior to recovery. As shown, the cable 3 is preferably provided with a suitable marking line 12 at a predetermined distance from another line 13 which represents the position of the end of the heat-recoverable sleeve 2 (FIG. 2). Preferably the distance between lines 12 and 13 is from 1 to 3 times the width of the V-strip. The V-strip 6 is itself preferably marked at 14 so as to indicate the necessary degree of overlap. The zone 14 may, for example, be coloured.
The width of the V-strip 6 is typically from 30 to 60 mm and the siliconed foil 8 preferably projects a further 20 to 40 mm beyond the lower edge thereof.
FIG. 6 shows the position of a single V-strip in cross-section on the line β--β of FIG. 2, and in FIG. 7 there is shown how, for a large diameter cable, there may be employed two V-strips 15 and 16 which overlap in areas 17 and 18.
FIG. 8 shows how the V-strip may be employed at a branch-off cable termination employing a clip 19 in accordance with the teachings of British Patent Applications Nos. 79.11713 and 79.11714. As can be seen the smaller branch-off cable 20 is provided with a single V-strip 21 whereas the larger main cable 22 is provided with two overlapping V-strips 23 and 24.
FIG. 9 shows how a pre-installed tubular V-strip 25 may be used in conjunction with a valve member 26. This valve member may, for example, be that used to pressurise the splice case.
FIG. 10 shows a further form of V-strip 27 which in this case is provided at its base 28 with a spring component 29 which is pre-installed, preferably with an overlap of 0.75 turns, and which operates to grip the V-strip firmly in place on a substrate such as a cable prior to recovery. | A heat-recoverable sleeve for enclosing splices or joints in pressurized cables or supply lines is given increased resistance to peeling away from the cable or line by insertion of auxiliary means, preferably a U- or V-shaped flexible strip, which may be heat-recoverable, between the sleeve and the cable or supply line. The ends of the strip are preferably closed and are preferably overlapped and bonded to each other when the strip is placed around the cable or supply line. A release foil may be positioned inside the U- or V-shape of the strip to resist bonding together of the opposed arms thereof, and the foil may carry adhesive to bond it to one of the arms and may protrude beyond the ends of the arms so that the foil adhesive can help to locate the strip on the cable or supply line. | 8 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention generally relates to electronic circuits and, more specifically, to microcontrollers of execution of instruction sequences, for example, integrated in devices of smart card type.
[0003] FIG. 1 very schematically shows in the form of blocks an example of an integrated circuit 1 of the type to which the present invention applies.
[0004] Such a circuit comprises at least a central processing unit 2 (CPU), one or several memories 3 (MEM) among which generally at least a non-volatile memory (for example, a ROM) for storing programs and a RAM for containing the data during execution thereof, and an input/output element 4 (I/O) for communicating with or without contact with the outside of circuit 1 . The different elements contained in circuit 1 communicate over one or several internal data, address, and control buses 5 , and other circuits (for example, sensors) may be integrated to circuit 1 .
[0005] The present invention more specifically relates to the protection of the execution of programs handling digital values supposed to remain within integrated circuit 1 against possible hacking attempts by fault injection in the program flow.
[0006] 2. Discussion of the Related Art
[0007] Integrated circuits containing digital values supposed to remain unknown from the outside (for example, keys used by cryptography mechanisms) are likely to be hacked by persons attempting to fraudulently implement methods for creating traps in the correct execution of programs. Such methods comprise the disturbing of the circuit operation during the execution of a program (for example, by a disturbance introduced on its clock) to cause an incidental jump from the program to another instruction than that normally expected. Such a jump may enable exiting a control loop, an endless loop following an authentication error, etc. and more generally may enable interpreting the consequences of this jump to discover, even partially, the secret quantities.
[0008] There exist different mechanisms to control the flow of programs executed by electronic circuits.
[0009] A known solution comprises the performing of a so-called signature calculation during the execution of a program to be sure that all instructions have been executed.
[0010] Another known solution comprises the execution of the same program several times in parallel and the checking of the coherence of the results obtained by these multiple executions.
[0011] A disadvantage of known solutions is that the very existence of a mechanism for protecting the program execution is not transparent for the user.
[0012] Another disadvantage is that these are mechanisms of detection of a trap attempt on a program which require, in case of a detection, for specific measures to be taken, and thus another program to manage possible fraud detections.
SUMMARY OF THE INVENTION
[0013] The present invention aims at overcoming all or part of the disadvantages of known solutions for protecting programs against possible traps.
[0014] The present invention more specifically aims at providing a solution avoiding the addition, to a trap attempt detection mechanism, of a mechanism for interpreting and processing this detection.
[0015] The present invention also aims at providing a solution which requires little resources and particularly easy to implement in a microcontroller of smart card type.
[0016] The present invention also aims at providing a solution which is not detectable by a possible hacker.
[0017] To achieve all or part of these objects as well as others, the present invention provides a method for protecting the execution of a main program against possible traps, comprising the steps of:
[0018] on occurrence of an instruction from the main program, starting a time counter of a given count according to next instructions of the main program; and
[0019] executing, once the counter has reached its count, at least one instruction of a secondary program from which the result of the main program depends.
[0020] According to an embodiment of the present invention, an instruction of the main program following a part of it the normal execution time of which corresponds to said count, provides a result which depends on at least one instruction of the secondary program and which is incorrect if said instruction of the secondary program is executed at a wrong time.
[0021] According to an embodiment of the present invention, the result of the main program is an arithmetical result.
[0022] According to an embodiment of the present invention, the result of the main program is the starting of a process.
[0023] According to an embodiment of the present invention, the counter is a cycle counter.
[0024] According to an embodiment of the present invention, the counter is an instruction counter.
[0025] The present invention also provides an integrated circuit comprising at least one central processing unit and memories, as well as means for implementing the protection method.
[0026] The foregoing and other objects, features, and advantages of the present invention will be discussed in detail in the following non-limiting description of specific embodiments in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] FIG. 1 , previously described, very schematically shows in the form of blocks an example of an electronic circuit of the type to which the present invention applies; and
[0028] FIG. 2 illustrates an embodiment of a mechanism for protecting the flow of a program according to the present invention.
DETAILED DESCRIPTION
[0029] For clarity, only those method steps and elements which are useful to the understanding of the present invention have been shown in the drawings and will be described hereafter. In particular, the content of the programs protected by the present invention has not been described in detail, the present invention being compatible with any program currently executed by a microcontroller.
[0030] A feature of an embodiment of the present invention is to provide, at a time of the execution of a main program to be protected, the starting of a counter which, when a given count will have been reached, will execute an instruction useful for the main program but within the framework of a secondary program. Another feature of this embodiment is to carry on with the execution of the main program during the counting and to provide the time of execution of the secondary instruction so that, in a normal operation of the main program, it occurs at an expected time.
[0031] In other words, the present invention provides transferring, to the execution of a secondary program, one or several instructions necessary to the obtaining of a correct result by the main program and causing the execution of these instructions independently from the flow of the main program after starting of a counter. Thus, in case of a trap on the main program, the instruction or the group of instructions of the secondary program will not be executed or will be executed at a wrong time, so that the results of the main program will be incorrect.
[0032] The instruction or the group of instructions executed in the secondary program are preferably instructions necessary to the main program to obtain the expected results. For example, this may be a step of an arithmetical calculation, the non-execution of which results in that the output result is not correct. According to another example, the non-execution of a step of the secondary program blocks a function of the main program, and thus the provided result (in a broad sense) is not correct. The result can thus be either the starting of any other process, or an arithmetical result.
[0033] FIG. 2 illustrates, in a very simplified view, an embodiment of the present invention.
[0034] The execution of a main program Pg comprising instructions INSTR and, within this program, a portion (PROTECTED), the execution of which is desired to be protected against possible traps, is assumed. Indeed, the entire program not necessarily requires protection but, most often, only phases implementing digital values supposed to remain within the circuits. In this example, the instructions which are desired to be protected range from instruction INSTRi+1 to INSTRi+k.
[0035] At the beginning of the area to be protected, instruction INSTRi starts a counter (TIMERj) by setting it to a value j=k. A time counter is here assumed (for example, a cycle counter), but any other adapted counter (for example, an instruction counter) may be appropriate if the number of increments/decrements to be brought thereto in a normal execution of the area to be protected of the main program can be determined. However, the incrementing/decrementing of the counter is independent from the execution of the program to be protected.
[0036] The main program continues its execution normally until instruction INSTRi+k.
[0037] According to this embodiment of the present invention, the instruction which follows instruction INSTRi+k in the main program is an instruction INSTRi+k+2, a correct result of which is conditioned by the execution of an instruction INSTRi+k+1 in a secondary program SecPg. Instruction INSTRi+k+1 is executed independently from the main program once counter TIMER has reached a value j=0.
[0038] The selection of instruction INSTRi+k+1 is decided on design to be necessary to the provision of a correct result by the main program or to a normal continuation of its operation after instruction INSTRi+k, without for all this being required between the instructions of rank i+1 to i+k of the main program.
[0039] In the case where a trap of the main program occurs in the protected area, this results in a jump. Such a jump, be it while remaining in the protected area or coming out of this area, modifies the time required to reach instruction INSTRi+k. Accordingly, instruction INSTRi+k+1 will not be executed at the right time and the result provided by the main program will be erroneous.
[0040] It should be noted that the main program does not wait for the execution of the instruction of the secondary program, but uses it (for example, an operation result not linked to the values of instructions INSTRi+1 to INSTRi+k) to carry on with its own execution. Thus, the present invention provides no waiting loop.
[0041] An advantage of the present invention is that the protection of the execution of the main program comes along with no interpretation after a fraud attempt detection. Indeed, the only consequence is the incorrect execution of this program. Thus, the protection performed by the present invention is transparent for the possible hacker who does not realize that the result which is output to him is erroneous.
[0042] According to a variation, several instructions may be called for by the secondary program.
[0043] According to another variation, several secondary counters and loops are provided either in parallel or in random selection by the main program.
[0044] Of course, the present invention is likely to have various alterations, improvements, and modifications which will readily occur to those skilled in the art. In particular, the selection of the instructions to be transferred from a main program to be protected to a secondary program is within the abilities of those skilled in the art according to the application. In particular, the practical implementation of the counter so that, for example, it counts to a value compared with the current value or until an overflow, is within the abilities of those skilled in the art. Further, the practical implementation of the present invention based on the functional indications given hereabove is within the abilities of those skilled in the art, using hardware tools or conventional programmings.
[0045] Such alterations, modifications, and improvements are intended to be part of this disclosure, and are intended to be within the spirit and the scope of the present invention. Accordingly, the foregoing description is by way of example only and is not intended to be limiting. The present invention is limited only as defined in the following claims and the equivalents thereto. | A method for protecting the execution of a main program against possible traps, including, on occurrence of an instruction from the main program, starting a time counter of a given count according to next instructions of the main program, and executing, once the counter has reached its count, at least one instruction of a secondary program from which the result of the main program depends. | 6 |
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