Abstract: A remotely changeable thermostat for a refrigeration or air conditioning system and method and system employing same. The thermostat has a fluid filled capsule with a diaphragm movably responsive to fluid expansion and contraction for actuating, via lever means, a compressor power switch. The capsule senses temperature via a fluid filled capillary. A separate remote user activated switch energizes an electrical actuator for moving the fulcrum of the lever means to change the sensed temperature of the evaporator at which the power switch is actuated. The user activates a remote switch to energize an electrical heater coil for heating a bimetal strip which moves the fulcrum for the lever means between a high or low temperature setting for compressor power switch actuation in response to user opening or closing the remote heater switch.

Abstract: An electronic controller receives a suction pressure sensor signal and measures the time required for the evaporator to be heated from compressor clutch cut-out to compressor clutch "ON". Depending upon the elapsed time, the controller selects from a predetermined schedule, a new value CLHOFF of the suction pressure P.sub.s at which the compressor is next cut-out, raising CLHOFF for lighter thermal loading to prevent evaporator icing and freeze-up and lowering CLHOFF for heavy thermal loading to prevent unwanted compressor cycling.

Abstract: A vehicle engine throttle valve control device (10;121) is applied intermediate the vehicle operator's accelerator pedal (14) and the engine's throttle body (12) to selectively override or modify the operator's ability to control vehicle/engine speed and to assert independent control thereof as a function of various input parameters (49,50,52,54). Linkages (26,28) interconnect opposed ends of a lever (18;136) respectively, with accelerator and throttle. The lever rotates upon a pivot (20;126) which is selectively displaceable to effectively shorten or lengthen the linkage in response to an operator independent signal from a control circuit (42).

Abstract: A make-before-break pressure switch has a pair of snap-acting discs separated by a travelling spacer. At a low level switching pressure, the travelling spacer is moved by the pressure sensing diaphragm to snap one disc for moving a contact blade to close a pair of contacts. On increasing pressure, the second disc is snapped at a high level switching pressure to cause a blade spring to go over-center and effect snap actuation of the contact blade to re-open the contacts. Upon decreasing pressure reverse operation occurs; and, the over-center blade snaps the blade to close the contacts which remain closed until a low level opening pressure is reached.

Abstract: At least one pair of light emitting diodes (LEDs) is disposed to direct a beam of common discrete chromaticity each to a separate target area located at different distances from a centrally disposed photodetector. Upon pulsing of the diodes at a common time, the photodetector receives the sum of the diffused light reflected from a target disposed at a location between the separate target areas to substantially reduce the affects of variation in distance of a target from the photodetector. The photodetector output is corrected for the effects on the LEDs of variations in ambient temperature.

Abstract: A pilot operated electromagnetically actuated valve having a flexible diaphragm main valve operator with a rigid insert forming the pilot valve seat and passage. The pilot valving chamber cover serves as an armature pilot valve guide and also has plural spaced ribs engaging and guiding movement of the rigid insert and pilot valve seat. A separate inlet passage having an annular filter formed by circumferentially spaced grooves and a resilient flange provided on a disc member inserted in the valve inlet flow to a remote pilot bleed hole in the cover for supplying the pilot valving chamber.

Abstract: A thermistor is employed for sensing refrigerant temperature in a refrigeration system and an electronic controller continuously measures changes in resistance of the thermistor as an indication of refrigerant temperature for generating a control signal for controlling compressor clutch and condenser for the thermistor is calibrated at installation by flowing constant temperature air over the thermistor, measuring the resistance of the thermistor, comparing the measured value with a standard value and storing the comparison in the microcomputer non-volatile memory or externally such as non-volatile memory, diodes, program PINS, etc. as correction factor for operational use in controlling the system with refrigerant flowing over the thermistor.

Abstract: A servo-actuator has a motor driven input pinion engaging a driven gear clutched to an output pinion. The driven gear has an internally notched hub and the output pinion has a central core with a tapered pin slidable therein. Spherical cams are slidably received in a cross hole and are moved outward to lock the output pinions to the hub when a solenoid is energized, to move the tapered pin into contact with the cam members. The angle of the notch and the pin taper are chosen to effect a positive de-energization force on the pin for facilitating disengagement.

Abstract: A rotary actuator for an appliance having a shaft with a radially outwardly-extending boss with a cam surface thereon locked in an "OFF" position between a stop and a detent lug. The user is required to move (push) the shaft axially in order to enable the boss to clear the detent to permit rotary movement away from the "OFF" position stop for affecting a control function. As the boss is rotated past the detent to the desired "ON" position, and upon user release, the shaft is spring biased to return to its initial axial position. Upon return rotary movement of the shaft by the user, the cam automatically moves the shaft axially to enable the boss to pass by the detent to return to the "OFF" position against the stop.

Abstract: A microswitch is mounted between the sides of a U-shaped channel bracket. The sides of the bracket are pulled together to clamp the switch therein by a screw passing through a hole in the switch body. Tabs extending from the edge of the bracket sides move the switch by camming as the sides are pulled together to cause one side of the switch mounting hole to be registered against the screw to maintain the switch securely in one position on the bracket.

Abstract: A capacitive switch assembly formed on a glass substrate with one capacitive plate formed of a thin metal film deposited thereon covered by a dielectric spacer deposited thereover for spacing therefrom a second plate formed of conductive polymer paste screened on the dielectric spacer. Discontinuities are provided in the second plate which is brought in-circuit by a conductive elastomer shorting bar movable upon user actuation of the switch.

Abstract: Pivotal movement of a switch actuator drives a finger projecting from the actuator against a convexly bowed leaf spring, depressing an intermediate portion of the leaf spring to an unstable concave condition. The leaf spring resists the actuator movement, initially with an increasing force but changing to a decreasing force at a predictable point in actuator movement to provide tactile feedback at an operator affixed to the actuator. The leaf spring is a flat beam. The spring force and point of changeover can be readily and predictably varied during manufacture by selecting springs having different widths, thicknesses or other variable parameters. A modular block holds the spring in the bowed condition and is positioned relative to the actuator finger by a support plate. The actuator finger drives the spring against a conductive rubber block, compressing the block against spaced conductors on a printed circuit to complete the circuit.

Abstract: A system for controlling vehicle passenger compartment comfort. An electronic controller receives input from: (i) a thermistor array sensing blower plenum discharge temperature, (ii) a user movable Level Select Control (iii) a potentiometer sensing the position of a servo driven heater core water valve, (iv) an engine rpm tachometer generator and (v) a blower speed signal. The controller employs proportional-integral-derivative (PID) strategy in a microprocessor to generate a control signal for operating the heater core valve servo motor to maintain the plenum discharge air at a constant temperature irrespective of wide swings in engine rpm/water pump speed or user selector changes in blower speed.

Abstract: A pressure sensitive pad assembly for a brake pedal having in one embodiment a pair of plastic films with metallized surfaces spaced apart by apertured spaces and embedded in an elastomeric pad to be placed on a brake pedal. Application of a brake actuating force on the pad causes the elastomer to deform closing contact between the metallized surfaces for actuating a brake light. In another embodiment a pressure sensitive transducer pad assembly has embedded in elastomeric material, a plurality of piezoelectric strips which are deformed, upon application of a brake actuating force to the pad, for providing an electrical signal indicative of the magnitude of the brake actuating force. In another embodiment an elastomeric pad spans a shallow recess in a support with piezoelectric material provided on the spanning surface and deformation of the pad into the recess deforms the piezoelectric material to provide a brake actuating force signal.

Abstract: A programmer for an appliance having a line power switch and a plurality of program switches sequentially actuated by a cyclic cam mechanism. The program switches are latched to the actuated condition and uplatched independently of the cyclic mechanism by electrically energized release mechanisms, individually controlled by an electronic controller having a microcomputer which employs a user selected programmed sequence.

Abstract: A rotary adjustment device adapted for user rotation to adjust the position of an adjacent mechanism such as the linkage for actuating an electrical snap switch. The device has an outer annular cam with a central hub structure with a shaft defining surface adapted for being rotatably journalled. The hub is suspended from the cam by torsionally stiff web structure which is radially inner an outer pairs of oppositely disposed spokes which permit resilient deflection, when unwanted side loads are applied to the shaft for preventing disturbances of the cam once the user has selected a rotary position.

Abstract: A mechanical refrigerant thermal expansion valve has a sensing port sealed with a cupped shaped closure received therein and sealed about the cup rim. A cover assembly is removably attached to the valve over the cup with a thermistor extending into the cup which is filled with thermally conductive grease for thermal conductivity between the cup and the thermistor. The cover assembly has an electrical connector provided thereon. The thermistor is preferably mounted on printed circuit board potted in the cover which may include electronic signal logic and power switching circuitry.

Abstract: An indicator providing an electrical indication of the positions of a user movable mechanical selector. The indicator base has a plurality of spring biased contact pins slidably contacting patterned conductive regions on the surface of the selector for completing a circuit through, or between the pins for indicating selector positions. The indicator base cover is telescopically mounted on the base with conductive springs connecting terminals provided in the cover with the pins. One pin has a shorting bar for providing an auxiliary current path. An annular seal about the outer periphery of the telescoping cover provides sealing about external casing structure. The indicator base is adapted for mounting about a common point axis for the movable selector for accuracy of location.

Abstract: A one-way ratcheting clutch having a primary annular driving member with a plurality of circumferentially spaced radially inwardly extending lugs and a secondary annular member mounted on a common shaft has a plurality of resilient circumferentially spaced outwardly extending fingers for engaging the lugs configured to be compression loaded. At any relative rotational position at least one, and less than half, of the fingers is in the relaxed or undeflected state to minimize the effects of permanent set where both members are formed of plastic and exposed to service temperatures up to 85.degree. C.

Abstract: An automatic control system for regulating the temperature of blower air discharged over a heater core to a vehicle passenger compartment. A thermistor is disposed to sense discharge air adjacent the heater core and provide a temperature signal. An electrical indication is provided of the condition of a servomotor driven valve controlling water flow to the heater core. An electrical reference signal is provided indicative of a user selected relative change of flow discharge air temperature. A signal is provided indicating inlet pressure to the valve controlling flow of liquid to the heater core. The signals are summed; and, the valve servo driven until the sum is zero modulating the valve to maintain the sum at zero for regulating blower air discharge temperature at a constant level.