Abstract: A proximity switch assembly (10) for signaling the location of a movable member (36) at either of opposite end limits of movement relative to a stationary frame (44, 46) includes a compact elongate housing (58) adapted to be mounted on the frame to extend along the path of movement of a power driven member (32), such as the piston rod of a hydraulic cylinder, which shifts the movable member between its end limits. The proximity switch is fixedly mounted in the housing and carries a switch actuating member (68) mounted for sliding movement over a relatively short distance sufficient to move an actuating target (74) into and out of actuating proximity of an air core proximity sensing coil (120) within the housing. Lost motion abutment shoulders (70, 72) on the switch actuation member and power driven member (54) move into engagement with each other as a power driven member approaches each end of its stroke.

Abstract: A process for making silicon nitride articles of manufacture such as an internal combustion engine valve (2) by providing a homogeneous water-base slurry of silicon nitride powder and at least one nitriding agent and permitting the slurry to age for a time effective to enable a chemical reaction to occur and then reducing the water content sufficiently to form the article and thence forming and nitriding the article using a compound nitriding cycle.

Abstract: A vehicle engine throttle valve control device (10) 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 an assembly of half levers (21,23) with accelerator and throttle. The half levers rotate upon a pivot (20) which is selectively displacable to effectively shorten or lengthen the linkage in response to an operator independent signal from a control circuit (42). A half lever stop (27) fixes the relative positions of the half levers whenever the throttle body is in an off-idle position.

Abstract: A tachometer sensor adapted for measuring the rotation of a gear or spline shaft target within a high pressure environment includes an integrally formed housing having a generally tubular elongate probe defining a sealed interior cavity receiving an annular permanent magnet at the sensing end thereof, field focusing means such as a ferrous pin disposed concentrically with the permanent magnet to shape the field established thereby, at least one magnetoresistive transducer concentrically disposed with the magnet to detect distortions of the magnetic field effected by passage of the target and means in-circuit with the transducer which generates a usable output signals as a function of sensed magnet field distortion.

Abstract: A proximity switch assembly (10) for signaling the location of a movable member (36) at either of opposite end limits of movement relative to a stationary frame (44,46) includes a compact elongate housing (58) adapted to be mounted on the frame to extend along the path of movement of a power driven member (32), such as the piston rod of a hydraulic cylinder, which shifts the movable member between its end limits. The proximity switch is fixedly mounted in the housing and carries a switch actuating member (74) mounted for sliding movement over a relatively short distance sufficient to move two actuating targets (104,106) into an out of actuating proximity of respective air core proximity sensing coils (132,134) within the housing. Lost motion abutment structure (76,78) on the switch actuation member and power driven member (54) move into engagement with each other as a power driven member approaches each end of its stroke.

Abstract: The present invention is a shaft position sensor for detection of the position of a multiturn shaft. The rotation of the multiturn shaft is converted into a linear motion via a multiturn screw and two axially spaced non-rotating nuts which are oppositely continuously axially biased by intermediate compressed springs. A magnet is mounted on one of the nonrotating nuts. The linear movement of the magnet is converted into an electrical signal using a magneto resistive structure. A pair of flux plates is disposed on either side of the linear path of the magnet with a narrow gap opposite one end of the linear path of the magnet. The magneto resistive structure is disposed in the narrow gap. An electrical circuit measures the resistance of the magneto resistive structure, this resistance varying with magnetic flux, and generates an electrical position signal which indicates the rotary position of the multiturn shaft.

Abstract: A system (20) for linearizing a non-linear transducer output signal (s.sub.2) which may be amplified to a non-linear output signal (s.sub.2) by suitable amplifier means (2) by providing signal (s.sub.2) to both a summing or linearization means (6) and an analog to digital converter which provides a signal (s.sub.3) to a storage means (4) which selectively provides a predetermined correction signal (s.sub.4) which is received by a digital to analog converter (5) to provide a signal (s.sub.5) to linearization means (6) for combination with signal (s.sub.2) to provide a linearized output signal (s.sub.6).

Abstract: An electroviscous fan clutch (10) is employed as an accessory drive mechanism within a truck or automobile. A shaft (36), either driven by the engine or driving a load (31), carries a clutch member (14) arranged for fluid engagement with a body member (12) for the transmission of torque therebetween when electroviscous fluid is disposed in an operating chamber (45) defined by complimentary shear surfaces (40 and 44) in the clutch and body members. The clutch and body members are electrodes, connected to a source of high voltage potential (86), which establish an electrostatic field within the operating chamber to selectively vary the characteristic viscosity of fluid flowing therethrough.

Abstract: An electroviscous fan clutch (10) is employed as an accessory drive mechanism within a truck or automobile. A shaft (36), either driven by the engine or drivig a load (31), carries a clutch member (14) arranged for fluid engagement with a body member (12) for the transmission of torque therebetween when electroviscous fluid is disposed in an operating chamber (45) defined by complimentary shear surfaces (40 and 44) in the clutch and body members. The clutch and body members are electrodes, connected to a source of high voltage potential (86), which establish an electrostatic field within the operating chamber to selectively vary the characteristic viscosity of fliud flowing therethrough.

Abstract: A viscous fan clutch (10) is typically employed in a fan drive mechanism within a truck or automobile. A shaft (18), driven by the engine (12), rotates a clutch member (42) within the fan drive. The clutch member is arranged for fluid engagement with a body member (60) for the transmission of torque thereto when fluid is disposed in an operating chamber (106) defined by complimentary shear surfaces in the clutch and body members (48 and 98), respectively. A tether assembly (30) operates as an actuator to displace a valving element (196) within the clutch to control the torque transmission there through and thus the speed of the output shaft and fan (34) thereof. Fan speed is regulated by variable current signal applied to a coil (174) within assembly (30) to selectively variably frictionally engage valve element assembly (196) with a grounded thrust surface or reaction member (190) to effect limited displacement of a valve element (198) in response thereto.

Abstract: A proximity switch assembly (10) for signaling the location of a movable member (36) at either of opposite end limits of movement relative to a stationary frame (44,46) includes a compact elongate housing (58) adapted to be mounted on the frame to extend along the path of movement of a power driven member (32), such as the piston rod of a hydraulic cylinder, which shifts the movable member between its end limits. The proximity switch is fixedly mounted in the housing and carries a switch actuating member (68) mounted for sliding movement over a relatively short distance sufficient to move an actuating target (74) into and out of actuating proximity of an air core proximity sensing coil (120) within the housing. A circuit board holder (96) formed of dielectric plastic material nests within the housing to protect, electrically insulate and precisely position components (120, 100, 102) carried thereby.

Abstract: A torque motor and throttle body are integrated within a single assembly for application with an internal combustion engine charge air inlet. The butterfly valving element of the throttle body and rotor of the motor are mounted on a common shaft, the position of which is established by a fly-by-wire control circuit. The rotor is selectively affixed to the shaft through an intermediate coupling which is excessible externally of the motor's closed stator assembly.

Abstract: A viscous fan clutch (10) is typically employed in a fan drive mechanism within a truck or automobile. A shaft (18), driven by the engine (12), rotates a clutch member (42) within the fan drive. The clutch member is arranged for fluid engagement with a body member (60) for the transmission of torque thereto when fluid is disposed in an operating chamber (106) defined by complimentary shear surfaces in the clutch and body members (48 and 98), respectively. A tether assembly (30) operates as an actuator to displace a valving element (196) within the clutch to control the torque transmission there through and thus the speed of the output shaft and fan (34) thereof. Fan speed is regulated by variable current signal applied to a coil (174) within assembly (30) to selectively variably frictionally engage valve element assembly (196) with a grounded thrust surface or reaction member (190) to effect limited displacement of a valve element (198) in response thereto.

Abstract: Automated manufacturing equipment (10) such as robot arms for performing a manufacturing operation on a work piece (12) have a relatively stationary host machine (14) with central programmable logic means (16) which receive various parametric inputs (26) and thereby control movement and operation of a machine element (18) suspended at the end of an articulated arm (20) for positioning with respect to the work piece in response to the control signals. A small programmable logic controller (30) disposed for movement with the machine element receives inputs and performs local AND/OR logic on a number of input signals from transducers (28) measuring various parameters associated with movable machine elements. The local I/O device then performs selective AND/OR ladder logic functions on the transducer output signals and outputs a single resultant signal as a function thereof in real-time to the central logic means.

Abstract: A current sensor (10) comprising spaced pole pieces (62, 64) and a magnetic shunt (80) bridging the pole pieces within an insulating housing assembly (12) which also contains a magnetoresistive transducer (90) and electronic circuitry (16) for sensing magnetic field intensity between the pole pieces and relating that intensity as electric signals provided at terminals (26) at the exterior of the housing. The transducer senses magnetic field intensity along a principal axis (88). Permanent magnets (94, 96) or induction coils (276, 278) are provided to establish a biasing component of magnetic field intensity along an axis (98) substantially normal to the principal axis to improve sensor sensitivity, range of operation and immunity to current overload.

Abstract: A viscous fan clutch (10) is typically employed in a fan drive mechanism within in a truck or or automobile. A shaft (18), driven by the engine (12), rotates a clutch member (42) within the fan drive. The clutch member is arranged for fluid engagement with a body member (60) for the transmission of torque thereto when fluid is disposed in an operating chamber (100) defined by complementary shear surfaces in the clutch and body members (48 and 98), respectively. A tether assembly (30) operates as an actuator to displace a valving member (158) within the clutch to control the torque transmission therethrough and thus the speed of the output shaft (and fan 34) thereof. Fan speed is regulated as a function of a sensed temperature of the host engine by a control circuit (176) which senses fan speed and coolant fluid temperature and generates a speed error signal as a function of temperature.

Abstract: A torque motor and throttle body are integrated within a single assembly for application with an internal combustion engine charge air inlet. The butterfly valving element of the throttle body and rotor of the motor are mounted on a common shaft, the position of which is established by a fly-by-wire control circuit. The control circuit includes a driver which selectively energizes the motor in response to the simultaneous receipt of both duty cycle and pulse with information. The control circuit further provides redundant outputs and transducers to enhance system failsafing.

Abstract: A system (20) for linearizing a non-linear transducer output signal (s.sub.2) which may be amplified to a non-linear output signal (s.sub.2) by suitable amplifier means (2) by providing signal (s.sub.2) to both a summing or linearization means (6) and an analog to digital converter which provides a signal (s.sub.3) to a storage means (4) which selectively provides a predetermined correction signal (s.sub.4) which is received by a digital to analog converter (5) to provide a signal (s.sub.5) to linearization means (6) for combination with signal (s.sub.2) to provide a linearized output signal (s.sub.6).

Abstract: A torque transducer (10) generates a signal representing torque applied to an input shaft (12) to the transducer. The input shaft is resiliently connected to an output shaft (14), permitting limited relative rotation between the two which is sensed by the selective shunting of an electromagnetic field. Multiple fields and shunting devices (76 and 78) are provided which coact complementarily (in shunting effect) to provide a usable signal throughout an entire range of operation. In application, the transducer is intended for electrically assisted vehicle power steering systems.

Abstract: An air throttle (10) for an internal combustion engine has a butterfly-vane (16) mounted for rotation in the engine charge air inlet (15). The butterfly-vane is mounted on a rigid tubular shaft (18) having an idle air bleed slot (22) therethrough with a tubular idle valve (24) slip fit within the shaft for concentric rotation therein. With the butterfly-vane closed for idle mode running, the idle valve is rotated between set limits established by abutment surfaces (26) and (36) defined by slot (25) to control idle air flow and idle speed. Upon rotation of the idle valve beyond the set limits, the butterfly-vane is progressively opened for off-idle mode running speed control.