A brake (10) capable of functioning as a disk brake and parking brake having engaged and disengaged modes of operation comprising: a piston rod (30) movable with the disk brake piston (14) having a threaded portion (40), a nut (60) rotatably movable on the threaded portion (40) relative to a first stop (52); a pressurizing device (80, 82, 84; 92) for pressurizing the fluid chamber (20) to move the piston (14) and piston rod (30) to respective engaged positions, and a motor (66, 68) for rotating the nut (60) in one of a) synchronism with pressurizing the fluid chamber and b) subsequent thereto so that the nut moves along the threaded portion (40) into a contracting position with the first stop (52) for preventing the piston rod (30) from moving from its engaged position to achieve the parking brake function.

Disk brake/parking brake with threaded piston rod and motor

A pneumatic pressure control arrangement for controlling the brakes of railway vehicles. A manual brake command controller converts a selected brake position into a corresponding electrical signal. An application magnet valve is connectable to a source of air pressure and to a storage device. A release magnet valve is connectable to atmosphere and to the storage device. An electropneumatic transducer senses the pressure in the storage device and provides a feedback signal. A microprocessor receives and compares the electrical signal with the feedback signal to develop an error signal which initially energizes the application magnet valve and the release magnet valve upon request of braking effort, and which subsequently pulses the application magnet valve when the pressure in the storage device is within a preselected control range, and which finally deenergizes the application magnet valve when the pressure in the storage device is within a preselected deadband range to cause a lap condition.

Digital air brake control system

A brake pedal actuation sensor includes an optical coupler. In a preferred embodiment: the optical sensor is carried by a housing; a shutter is provided to interrupt the optical coupling according to the distance between the housing and a bearing; the shutter is carried by the bearing; and the distance between the housing and the bearing is dependent upon the force applied to the brake. Additionally, a circuit responsive to an output of the optical coupler is provided for generating an electrical output signal indicating brake pedal actuation.

Pressure sensitive signal device for vehicle brake pedal

A braking system (8) comprising: a master cylinder (10); rear brakes (12a,b) communicated to the master cylinder (10); front brakes (14a,b) hydraulically isolated from the rear brakes; an isolation valve (16; 16') interposing the master cylinder (10) and the front brakes (14a,b) having a first state communicating the master cylinder to the front brakes and a second state isolating the master from the front brakes and connecting a pump (42) to the front brakes; a motor (44) for powering the pump (42); a reservoir (54) communicated to an inlet of the pump (42); a control unit (40) for causing front brake pressure to follow rear brake pressure comprising: a first pressure sensor (30) for generating a signal indicative of rear brake pressure; electric proportioning device (94) for generating a commanded front brake pressure signal (P C ); a second pressure sensor (32) for generating a signal of actual front brake pressure (P A ); a comparator (96) for comparing the command brake pressure signal to the actual brake pressure signal and for generating an error signal (P E ); a motor control circuit responsive to an error signal for activating the motor and for powering the pump (42).

Electro-hydraulic braking system

A vehicular brake lever arrangement is shown as having a brake lever pivotally supported at one end and a swingable other end provided with a pad for the application of a braking force thereto; a brake rod linkage leading to the vehicular braking system is pivotally connected to the brake lever as to have a slight translational movement relative to the brake lever; and a force sensitive resistor is placed as to experience a force thereagainst as such translational movement occurs between the brake lever and brake rod linkage.

Signal mechanism responsive to force applied to vehicular brake pedal and the like

A control system operates electro-pneumatic braking apparatus on a vehicle and includes an actuator for producing a signal proportional to desired braking effort from full release mode to a maximum. Sensor apparatus is responsive to a pneumatic parameter of the braking system for producing a signal indicative of the actual brake pressure while summing apparatus is responsive to the actuator apparatus and the sensor apparatus for producing outputs effective to operate the braking apparatus to release, apply, and lap modes in accordance with a selected difference in magnitude between the actuator apparatus and sensor apparatus signals.

W Matthews

Papers

Electronic brake control system