Lectron Products, Inc.

Eaton Corporation

Ford Motor Company Limited

Delphi Technologies, Inc.

The Bendix Corporation

Bendix Autolite Corporation

Paul A Michaels

Irvin B Rea

Harold R Macks

Henry J Ewald

Kenneth G Slotkowski

Joseph F Supinsky

James D Bode

William G Wolber

Thomas J Waraksa

David L Kaleita

James A Poirier

Charles J Ahern

Sherri A Slaughter

Robert F Spitz

Kevin I Young

Michael R Smith

A rotary transformer includes a resonant circuit and a coil drive circuit. The resonant circuit includes a resonating capacitor connected to a power MOS transistor, coupled across the primary coil of the transformer. The coil drive circuit includes a diode connected to a power MOS transistor coupled across the primary coil of the transformer. A microprocessor detects changes in the voltage across the primary coil. The resonant circuit is connected and disconnected from the transformer during a power transfer mode and a data transfer mode, respectively. During the power transfer mode, stored energy in the leakage inductance of the primary coil is used for power coupling, via the resonant circuit, instead of being dissipated as heat. The resonant circuit is disconnected from the rotary transformer during the data transfer mode to maximize bandwidth for two-way data transfer between the primary and secondary sides of the transformer. The transformer uses a synchronous mode of operation in which the power MOS transistor of the coil drive circuit is turned on when the voltage across the primary coil changes from a positive to a negative value during the power transfer mode. The synchronous mode of operation virtually eliminates a current spike through the diode of the coil drive circuit and provides the microprocessor an appropriate amount of time to recognize the voltage changes across the primary coil.

Rotary transformer with synchronized operation

A system for calibrating an electronic compass for a vehicle of the type employing a Forward and Lateral magnetoresistive magnetic field sensor. As the vehicle changes headings, the system periodically samples and digitally stores the peaks of the sensor outputs. When the stored peaks indicate a minimum change in the output of the sensors, the system microcomputer calculates a &ldquo;box&rdquo; surrounding the subscribed arc of heading changes and computes the center of the &ldquo;box&rdquo; as the center of the locus of anticipated peaks for all quadrants and shifts the locus (i.e., &ldquo;box&rdquo;) to be within the domain of the A/D converter to prevent saturation, which could otherwise occur in the presence of strong remnant magnetic fields in the vehicle. The &ldquo;box&rdquo; is updated with each sampling of sensor outputs until the vehicle is eventually headed through all four cardinal compass headings, and the compass is then considered to be fully modeled in the microcomputer.

Accelerated calibration for electronic compass module

A loosely coupled rotary transformer includes a resonant circuit, such as a resonating capacitor connected to a power MOS transistor, coupled across the primary coil of the transformer. The resonant circuit is connected and disconnected from the transformer during a power transfer mode and a data transfer mode, respectively. During the power transfer mode, stored energy in the leakage inductance of the primary coil is used for power coupling, via the resonant circuit, instead of being dissipated as heat. The resonant circuit is disconnected from the rotary transformer during the data transfer mode to maximize bandwidth for two-way data transfer between the primary and secondary sides of the transformer. Including the resonant circuit in the loosely coupled transformer optimizes data and power transfer without requiring the use of high-cost, high-efficiency magnetic structures in the core of the transformer.

Loosely coupled rotary transformer having resonant circuit

The disclosed invention comprises an electronic control circuit for transferring power and data signals between an electronic circuit associated with a vehicle steering column and an electronic circuit associated with a vehicle steering wheel. Communication between the column circuit and the wheel circuit is accomplished by a rotary transformer having a primary and a secondary magnetic coil, wherein the primary magnetic coil is associated with the steering column and the secondary magnetic coil is associated with the steering wheel. The column circuit and the wheel circuit both include data signals that are transferred to the other across the rotary transformer. The column circuit also includes a power supply which provides power to the wheel circuit across the rotary transformer. Power supplied to the wheel circuit is stored in at least one storage device in the wheel circuit, which then provides the power to the components of the wheel circuit, including an air bag squib driver circuit for firing air bag squibs.

Circuit and method for establishing two-way communication between the

An encryption process for a rolling code of a remote keyless entry system. The encryption process makes use of a command code shift register, a security code shift register, and a sequence code shift register in which the contents of these registers is transmitted from a portable transmitter to a receiver associated with the vehicle in order to perform a desirable function. The command code shift register provides the code of the function to be performed and the sequence code shift register provides a sequence code for updating the sequence of the receiver. The security code shift register includes a security code which is updated by a first and second pseudo random number generator after each transmission. Each of two pseudo random number generators include associated shift registers and exclusive NOR gates such that a first bit location and a tap bit location of each of the shift registers are exclusively NORed to provide a first bit location in the shift register. A series of the bit locations of the first and second shift registers are exclusively ORed together to set the bits of the security code register.

Rolling code encryption process for remote keyless entry system

A passive keyless entry system is specifically adapted for use with automotive vehicles. The system includes a portable beacon that is carried by a vehicle operator, a receiver/controller located in the vehicle, and an antenna connected to the receiver/controller for receiving an encoded transmission from the beacon. The system is designed to automatically unlock the vehicle as the operator approaches the vehicle. The system is further designed to automatically lock the vehicle as the operator, carrying the beacon, moves away from the vehicle. The beacon includes a motion sensor to conserve battery life when the beacon is stationary. Transmission between the beacon and the receiver/controller is characterized by a magnetically coupled radio frequency signal embodying differential phase encoded data with error correction coding of the data to enhance noise immunity and signal discrimination. In addition, the transmitted signal between the beacon and the receiver is continually changing in order to deter theft. A clock in the receiver/controller is automatically reset to a clock code of the encoded transmission if the transmitted signal is valid.

Rolling code for a keyless entry system

A vehicle compass system that is adapted to be calibrated in the assembly plant during final assembly of the vehicle. In particular, two factory calibration modes are disclosed: an automatic factory calibration mode wherein the calibration sequence is automatically initiated upon the occurrence of a uniquely definable event on the assembly line, and a manual factor calibration mode wherein a calibration button sequence is actuated at a specified location on the assembly line. In addition, an automatic adaptive calibration process is disclosed which continuously updates the calibration constants each time valid new heading data is obtained. In particular, heading vectors for the four main N, S, E, and W heading directions are calculated and stored in memory when the system is initially calibrated. Thereafter, whenever new heading direction data is obtained, the value of the new heading vector is used to update the value of the closest of the four main heading vectors. A new center calculation is also performed using the updated values and if the result is outside a tolerance window, the calibration constants are changed accordingly.

Method and apparatus for calibrating a vehicle compass system

An automatic headlamp dimmer system for switching a vehicle's headlamps from high beam to low beam when lights from another vehicle are detected in front of the vehicle. To prevent spurious responses to reflected light from signs and other sources, the dimmer system includes a light detector which is responsive only to infrared light. Also, unwanted responses to flashing lights are avoided by detecting the presence of a periodically varying light signal, and inhibiting switching between high and low beams in response thereto. The system is also capable of sensing the activation of windshield wipers and preventing headlamp switching caused by interruption of light to the system's light sensor by action of the wiper blades.

Automatic headlamp dimmer having improved signal discrimination and

Automatic headlamp dimmer

A vehicle light sensor for controlling light responsive systems such as an automatic headlamp dimmer. The sensor includes an enclosure containing a lens and a photo responsive detector. An optical chamber within the enclosure permits unwanted light from reaching the detector. A series of baffles within the chamber prevent light from outside a desired entrance angle from reaching the detector. A thin-film aperture is attached to the detector for controlling the size and shape of the detector's field of view. Gray scale shading may also be incorporated into the aperture to reduce the intensity of incoming light in selected portions of the field of view. An adjustment mechanism provides very fine angular view adjustments, beyond what is practical by simple assembly of molded parts.

Automatic headlamp dimmer with optical baffle

An improved electronic controller for an automobile power seat system is disclosed. The electronic controller features a microcomputer which receives command signals from a first and second group of operator actuable switches, present position signals from a monitoring circuit, and stored position signals from a memory circuit for generating control signals for directing a motive power means to adjust the position of an automobile seat. The monitoring circuit includes transducer means for sensing the current draw from the d.c. power source, and differentiating means connected to the transducer means for generating a pulse concomitantly with each commutation of the motor from the motive power means. These pulse position signals are sent to the microcomputer and then counted by an internal timer for determining the present position of the automotive seat. These pulse position signals are used to determine a 'stall' condition which occurs when the rack mechanism has encountered a mechanical stop, such as when the seat reaches its full forward position. The time between these pulses is monitored and a stall condition is determined when the time between these pulses exceeds a predetermined period.

Memory power seat controller

A surface acoustic wave convolver (10) with parabolic horns (16, 18), a typical horn (16) having a compensating stub (16a) at the horn input end (16b) disposed centrally on the horn longitudinal axis (19) to maintain the phase coherence at the horn output end Z(16c) of a wave traversing said horn (16).

Surface acoustic wave convolver having a horn central ray transit time

A wide range combustion mixture air/fuel ratio sensor in which an electrochemical cell supplies hydrogen gas to a palladium sensor element at a rate regulated by the output of a Wheatstone bridge circuit incorporating the sensor element. This generated hydrogen gas combines with any oxygen present in the exhaust gas through catalytic action and also maintains the level of absorbed hydrogen, and therefore the electrical resistance of the palladium sensor element, at a preselected value. The magnitude of the current applied to the electrochemical cell necessary to maintain this balance is a measure of the combustion mixture air/fuel ratio.

Growing community of inventors

Livonia, MI, United States of America

Paul A Michaels