Abstract: An axle assembly includes an axle defining an axis, a wheel assembly rotatably supported on the axle for rotating relative to the axle axis, a magnet, a sensor responsive to the magnet for producing a count signal, and a microprocessor for receiving count signal data, calculating the distance the wheel assembly has traveled, and transmitting distance data to an output device. The sensor is mounted to rotate with the wheel assembly and the magnet is mounted to the axle, at a position eccentric to or radially offset from the axle axis. The sensor is mounted to the wheel assembly in radial alignment with the magnet such that rotation of the wheel assembly aligns the sensor for magnetic interaction with or responsiveness to the magnet once per revolution of the wheel assembly.

Abstract: A method and system for detecting wheel slippage uses a turn sensor to detect a vehicle turning radius in order to predict the difference in wheel speed between wheels on the outside of the turning radius and wheels on the inside of the turning radius. The turn sensor detects the turning radius of the vehicle and signals a controller. The controller utilizes the signal from the turn sensor to predict a difference in wheel speeds between the wheel to the inside of the turn and the wheel to the outside of the turn. One of the driven axles includes wheel speed sensors mounted at opposite ends of the axle. The controller receives signals from each of the wheel speed sensors to determine an actual differential wheel speed. The predicted speed differential is compared to the actual speed differential and any difference between the two indicates wheel is slippage.

Abstract: A system for determining the amount of material in a brake lining includes a frictional brake surface and a brake lining having a sensor for producing an output signal indicating the temperature of the sensor. A brake actuation system actuates the brake lining against the frictional brake surface and, thereafter, releases the brake lining from the frictional brake surface. A timer measures a time period beginning when the brake lining is released from the frictional brake surface and ending when the sensor output signal reaches a return point indicative of the brake lining having cooled. A controller compares the measured time period to electronically stored predetermined values to determine the thickness of the brake lining. The invention further includes a method for determining the amount of brake lining material based upon this structure.

Abstract: A brake shoe assembly includes a brake lining and a housing. The brake lining has a predetermined thickness which gradually wears away and increases in temperature during a vehicle braking application. The housing is positioned to wear away and increase in temperature concurrently with the brake lining. An electrical wear loop circuit is encapsulated in the housing for directing power from a power source to a remote indicator in response to a wear opening in the loop circuit. A thermally sensitive switching element is encapsulated in the housing and connected in electrical series with the wear loop circuit for directing power from the power source to the remote indicator in response to the temperature of the housing exceeding a predetermined temperature threshold.

Abstract: An axle assembly includes an axle, a tire having a predetermined air inflation pressure rotatably supported on the axle, and a tire inflation system for detecting an actual tire inflation pressure less than the predetermined air inflation pressure, replenishing the tire with air, and producing an inflation signal. An inventive electronic recorder receives the inflation signal, increments a count register, and transmits count register data to an output device. In a first embodiment of this invention, the electronic recorder is mounted at an easily accessible location on a vehicle which includes the axle assembly. In a second embodiment of this invention, the tire is mounted to a wheel assembly and the axle assembly further includes an electronic hub odometer for detecting a revolution of the wheel assembly and producing an odometer signal.

Abstract: A two buss system to accomplish; 1) communication from contact pairs located at vehicle access points such as a vehicle door or trunk to a central controller; and 2) transmitting current for energization of actuators to implement respective commands such as normal lock or super lock. The contact pairs function to provide entry ports for commands as well as providing status signals of various points of interest. The contact pairs are connected to individual output ports of a counter. Each contact pair is sequentially pulsed by a single pulse of a pulse train provided by the central controller. If a contact pair is engaged or closed when pulsed, the pulse will cause a coincident buss loading to occur. The central controller monitors buss loading and is appraised of the contact status by the coincidence (or lack thereof) of a pulse and a respectively loaded buss.

Abstract: A light curtain system having a series of light emitting diodes is arranged to produce a beam of light which is modulated at about 40 KHz. The light is broadcast across a physical space in which intrusion detection is desired and received by respectively arranged photo diodes. Each of the light emitting diodes is connected in parallel to a single modulated power supply. Each photo diode produces an electrical signal having a magnitude which is proportional to the amount of light incident thereon. The signal produced by each photo diode is sequentially sampled and then compared to a reference value. If an intrusion in the respective region of the light curtain has occurred, the magnitude of the sampled signal will be less than the reference value providing indicia of an intrusion. Upon such a detection, the light curtain system provides indicia of the intrusion such that consequential remedial action in response thereto may be performed.

Abstract: A antilock brake system utilizes a microprocessor controller to monitor the rate of speed decay of a braked wheel of a vehicle and to cause release of braking force under incipient wheel lock-up conditions. The microprocessor receives a single digital wheel speed input signal and processes the latter in accordance with a program whereby a reference signal is generated and is periodically compared with the wheel speed signal to determine if a lock-up condition is in progress. The microprocessor compares the speed signal with the reference signal at frequent sampling intervals and when the wheel speed decreases at a rate exceeding a desired value, the reference signal is varied by the microprocessor to decrease at a predetermined first rate of decrement until the wheel speed signal and the reference signal correspond to each other, indicating that the wheel speed is dropping at a rate in excess of a desired rate of speed decay.