Abstract: A method and apparatus for verifying proper operation of a vehicle anti-lock braking system includes pressure measuring devices which are releasably attached to an exterior surface portion of the flexible wheel brake hoses. Each measuring device senses changes in the external diameter of the associated hose, which changes are representative of fluid pressure changes within the hose. The valving in the braking system is tested by applying fluid pressure to the system, operating the associated valves in a predetermined sequence, and monitoring the pressure changes in the associated wheel brake hoses to determine whether the valving is operating properly.

Abstract: An efficiency monitor circuit for an antiskid system is provided. The efficiency of the antiskid system is determined by monitoring the antiskid signal as to peak positive and peak negative moves thereof. The difference in these two signals corresponds to the efficiency of the antiskid system. This difference signal is compared to a threshold signal for comparison of the efficiency to a signal corresponding to an acceptable minimum value. Should the efficiency of the antiskid system fail to meet the minimum value, an alarm is activated.

Abstract: A device for testing the correct functioning of a slip-controlled brake system is connected to the electric signal and control lines of the brake system by means of a multiconductor plug (2) instead of a central electronic controller pertaining to the brake system. The individual testing operations are initiated one after the other from a control panel or manual control unit (1) by means of a test step switch (11). Disposed in immediate proximity to the multiconductor plug (2) or combined with the latter in a single unit is a shell (3) containing electric or electronic switches or circuits (5,6,7) which can be switched over by means of signals triggered from the control unit (1) for carrying out the testing operations.

Abstract: A vehicle monitoring device 10 consists of a damped-pendulum transducer 12 coupled to a potentiometer 14. The analog output of the potentiometer 14, following a braking test with the vehicle concerned, is sampled in a peak/trough detector 16. A microprocessor 18 comprising signal processing unit 20 and arithmetic unit 22 controls the sampling and sums, averages and displays the output of microprocessor 18 on a digital display 24. If desired, a suitably programmed small computer may be used in place of microprocessor 18. According to one aspect of the invention, the device 10 is adapted to serve as a brake-efficiency meter. In this case, the display 24 will be arranged to display the average, or currently-measured, deceleration, as the case may be. In an alternative application, the device 10 is adapted to serve as a safe-slope meter.

Abstract: A relatively small portable tester to test operative electric and pneumatic systems of vehicular trailers without use of an associated truck tractor. The tester provides a separated radio operated control module that allows visual inspection of the various electric and pneumatic systems by an operator while such systems are operated. The invention is interconnected to a trailer's systems by existing connectors without any required modification and provides self-contained pneumatic and electrical powering devices.

Abstract: An anti-block control system has four identically designed control channels. Safety circuits (8, 8') are also provided for monitoring the system, as are devices for testing the operability of the system. In this test, performed while the vehicle is stopped or when it is started, a test signal is fed into the channels and the effects of this signal are compared, in pairs, at locations of the controller corresponding to one another. A signal train is formed when the comparison is made. In accordance with the invention, two safety circuits (8, 8') are provided, each associated with a pair of channels, and the signals from all the channels are supplied, in pairs, to the safety circuits. The safety circuits include timing elements. During a test cycle, the signal trains in the two channel pairs generated by using the test signal are compared with one another by use of two comparator circuits (23, 23'), and in the case of non-agreement, a warning or switching signal (18, 18', 31) is generated.

Abstract: A device for testing an air brake system of a locomotive, an air brake system having a compressed air source, a conduit for the ingress and egress of compressed air and a brake valve which is communicatively connected to both the compressed air source and the ingress/egress conduit. The device is particularly for testing the functionality of the brake valve of the air brake system. The testing device includes a trackside stand for placement in proximity to a locomotive servicing site, and a storage reservoir for holding a predetermined volume of compressed air. The trackside stand is further comprised of a conduit having one end for communicative connection to the storage reservoir and an opposite end for communicative connection to the ingress and egress conduit of the locomotive air brake system.

Abstract: Apparatus for sensing the force necessary to pull the lever arm of an automobile parking brake to a predetermined position. An elongated body includes a cavity for receiving the lever arm of the parking brake assembly. The body includes a switch arranged to come into contact with portions of the parking brake assembly when the lever arm is lifted to a predetermined position. A transducer is operative to measure the amount of force required to lift the lever arm to the position at which the switch contacts the parking brake assembly.

Abstract: A device for testing a hydraulic circuit including the actuating cylinder and piston therefor. The testing device comprises a unitary assembly which is adapted to be clamped to the cylinder to be tested and which actuates the piston for pressurizing the associated hydraulic circuit. Sensing elements are incorporated for sensing the pressure applied to the hydraulic circuit and for sensing the amount of travel of the piston of the actuator during a given time period. In this way leaks or flaws in the hydraulic system may be readily detected.

Abstract: A testing apparatus for an anti-lock control system for vehicle brakes for testing the correct functioning of the control system. In one embodiment, the apparatus establishes a predetermined speed and compares this predetermined speed to the speed sensed by the sensing portion of the control system. When the predetermined speed is exceeded by the moving vehicle a testing apparatus is triggered which initiates a test procedure for the control system. The apparatus includes a switching device to insure that a test procedure is initiated only after the vehicle ignition switch is actuated. In another embodiment, the apparatus employs a temperature sensor and/or the control system output for initiating a test procedure, but not during a deceleration of the vehicle. In a further variant, two threshold levels are established, each of which must be encountered before the test procedure is initiated.

Abstract: A method for locating defects in a hydraulic brake system, in which a master cylinder is in communication with the outlet port of a compensating reservoir, which includes the steps of placing a measuring burette on the compensating reservoir's outlet port and operating the brakes to measure and determine the volume of brake fluid that flows from the master cylinder to the compensating reservoir when the brake is applied. A compensating reservoir making use of the method includes a measuring opening adapted to be closed by a measuring burette positioned above the outlet port of a compensating reservoir which outlet port is in communication with the master cylinder. Where the compensating reservoir includes a float acting as a level indicator, which is connected by a rod to a circuit operating contact piece or member, the rod is hollow and is arranged to pass through the float and the contact piece.

Abstract: The invention relates to improvements in testing apparatus for brake systems including a diagnostic unit provided with a brake cylinder having a selectively switchable magnetic valve adapted for assembly with an outlet line leading to said cylinder. The magnetic valve actuates a double-acting valve that controls the outlet line and a return line and a sensor associated with said magnetic valve is arranged to operate the same under varying pressure conditions.

Abstract: The time duration of output pulses from the transducer, including wave-shaping circuits, if used, is measured and compared with respect to predetermined time limits. Two sequential pulses are measured and stored. If both pulses are shorter than a predetermined time interval, no alarm signal is generated; if the first pulse is longer than a predetermined time interval and the second also longer than a predetermined time interval, an alarm signal generation circuit, otherwise activated by the second, longer signal, is inhibited (since acceleration or deceleration of the wheel is indicated); if, however, the time duration of the second sequential pulse is longer than a predetermined time interval, but the time duration of the preceding pulse is shorter than its time duration threshold value, the malfunction signal is not inhibited, indicative of malfunction, loose contacts, or the like.

Abstract: Apparatus for the determination of the brake actuation and release time for pneumatic brake systems. The brake tester is pneumatically connected to both an external source of pressure and the vehicle reservoir with a solenoid valve disposed between the external source and the vehicle reservoir so that an operator may incrementally increase the pressure within the reservoir. The brake tester includes a timing circuit which begins to run upon movement of the vehicle brake pedal and stops upon the attainment of predetermined pressure value within the vehicle brake chambers. The timing circuit also includes memory means to store the results of the brake actuation test so that both a brake actuation and release test may be sequentially conducted without interruption.

Abstract: Disclosed herein is a manually operated control valve wherein a pressure regulating valve and exhaust valve are contained in the same housing with intercommunicating passages, both valves having actuating plungers which are operated by a single manual operating means, such as a lever. The invention includes apparatus for testing vehicle pneumatic braking systems wherein the manually operated control valve is used in conjunction with a pressure gauge to test the system by controlling the supply and exhaust of air to and from the vehicle braking system and observing accompanying variations in pressure.

Abstract: The brake block has incorporated means such as strain gauges for measuring dynamic brake forces in two normal coordinate directions.

Abstract: A housing of the apparatus has a device for connection to a source of pressurized air, and is provided with first and second connectors for connection to brake system lines. A compressed air tank is located in the housing, and at least three double manometers are provided. Fluid couplings are connected with the manometers. A first fluid line connects the air tank with the device and has a one-way valve and an adjustable pressure regulator interposed in it, a second fluid line connects the air tank with the first connector, and a third fluid line connects the air tank with the second connector and has a one-way valve interposed in it. A multi-position manually operable air spring regulating valve is interposed in the second line and has a valve body, an operating handle for moving the valve body between two operative end positions and a centering-spring arrangement for centering the handle in a rest position in which the valve body is in an intermediate blocking position.

Abstract: Integrity checking apparatus including an indicator lamp on each car of a transit train equipped with electropneumatically controlled brakes, said lamp being illuminated when the application magnet valve operates to effect a brake application and remaining illuminated until a stick circuit, which is closed by the brake application operation to keep said lamp illuminated, is interrupted by operation of the release magnet valve in releasing the brakes, thus providing a positive means of monitoring the integrity of both the application and release magnet valves during a terminal test of the brake system.