Abstract: An anti-locking brake module comprises a housing having a first port coupled to a brake pipe, a second output port coupled to a brake cylinder, and a third port coupled to atmosphere. A blocking valve is in fluid communication with the first port and a vent valve is in fluid communication with the blocking valve, the second port and the third port. At least one sensor is coupled to an axle on the railcar. A microprocessor coupled to the blocking valve, the vent valve and the at least one sensor is configured to calculate one of a wheel speed of the railcar axle and a deceleration rate of the railcar axle based on signals received from the at least one sensor, and compare the calculated one of the wheel speed of the railcar axle and the deceleration rate of the railcar axle with a reference value. In response to the comparison, the blocking valve and the vent valve are activated to vent brake cylinder air pressure out of the third port. A power supply is operatively coupled to the microprocessor.

Abstract: In a vehicle braking system having a slack adjuster with an actuator and an electrically operable car control unit, an electrical switch is responsive the position of the actuator and is coupled to the car control unit to provide an indication of the condition of the vehicle brake shoes, i.e. whether or not the brake shoes are disengaged from the vehicle wheels.