Abstract: A hydraulic braking system for controlling the hydraulic pressure of the brake actuator and wheel cylinders includes a dynamic hydraulic pressure control system which transmits boosted hydraulic pressure in response to movement of a brake pedal. A master cylinder receives brake fluid pressure from a reservoir and transmits the fluid pressure from a pressure chamber in the master cylinder to a changeover valve. The changeover valve changes over the connection between wheel cylinders of the vehicle and the dynamic hydraulic pressure control system when the powered pressure which is transmitted from the dynamic hydraulic pressure control system is less than a predetermined pressure. A valve member of the changeover valve is movable between a first and second position so as to transmit the powered hydraulic fluid from the boost pressure chamber to the wheel cylinders of the rear wheels in a first position and block the transmission of the fluid in the second position.

Abstract: Flanged steel wheels remain in service on rail cars, locomotives, and other heavy rail guided machinery unitl they no longer maintain minimum specified rim or flange profile dimensions. If the rim or flange profile of the wheel cannot be returned to minimum specifications by surface machining operations, the wheel is condemned as being defective and is removed from service and scrapped. It is desirable to use an automated inspection device to determine if a wheel is approaching this condemning limit of profile wear. The invention automatically detects profile defects upon passing the wheel between rail mounted antennae which form a resonator cavity and transmit microwave radiation. When influenced by a wheel possessing condemnable rim thickness, flange thickness, or flange height profiles, the antennae cause a D.C. voltage to propagate at a microwave detector inserted into an interconnected comparison bridge network.

Abstract: Warning lights at a railroad grade crossing are energized at a predetermined flash rate when a train is approaching through the use of an essentially fail-safe solid state crossing controller employing circuitry that is active in creating an off condition of the warning lamps. A controller unit operates a pair of warning lamps alternately in synchronism with a warning rate (flash rate) signal having a predetermined repetition rate, such as 55 pulses per minute. When the crossing is safe, an RC circuit in the lamp driver responds to a 500 Hz safe status signal by providing continuous control excitation to a normally conductive lamp switching circuit to maintain the lamps deenergized. In a failure mode, the normal condition of the switching circuit maintains one lamp of each pair continuously energized.

Abstract: In an anti-lock automotive vehicle brake system comprising a vacuum brake power booster, a considerable reduction of manufacturing and assembling costs is obtained while the system's reliability in operation is simultaneously augmented by the incorporation into this brake system of a second movable wall arranged within the vacuum brake power booster to which a controllable pressure differential may be applied. The wall isolates two pneumatic working chambers and, in the case of slip control, is movable in a direction opposite to the actuating direction of the master brake cylinder by two compensating cylinders which are connected with the master brake cylinder pressure chambers. A hydraulic chamber which is normally in communication with an unpressurized pressure-fluid supply reservoir is sealed from the reservoir by a retention valve during slip control to hydraulically prevent brake petal induced pressure from being applied to the master cylinder.

Abstract: A control system and method for a brake system with anti-locking and/or traction slip control and sequential brake pressure modulation. A modulator pressure pattern is formed in a circuit (33) by measuring and evaluating variables determining the pressure in the control chamber of chambers (21) of a brake pressure modulator (4). The modulator pressure pattern represents, by approximation, the course of pressure in the modulator (4). This modulator pressure pattern is considered in the brake pressure control, that is in determining the excitation periods of the multi-way valves (13-16, 22, 23, 25) determining the pressure in a modulator chamber (21) of the brake pressure modulator (4) and in the wheel brakes (9-12). The pressure pattern is formed by integration of the valve excitation periods of the pressure increase and pressure decrease characteristics of the modulator (4) under consideration or of the entire system.

Abstract: A track clamp assembly for supporting or splicing tracks of I-shaped cross-section formed by a vertical web with horizontal parallel flanges at the opposite ends of the web and having a pair of oppositely facing grooves formed in the flanges on each side of the web. The track clamp assembly comprises upper and lower clamp members respectively having upper and lower edges insertable in a pair of track grooves, and having interengageable ramp surfaces disposed between the upper and lower edges and extending obliquely thereto. Outwardly projecting tabs on the clamp members are engageable by a connecting bolt which when tightened moves the ramp surfaces into interengagement, increasing the dimension between the upper and lower edges and forcing the clamp members into locking engagement with the track.

Abstract: In a hydraulic anti-lock braking system a modulator incorporates a solenoid-operated valve responsive to anti-lock signals, a re-application valve and an expansion chamber to which fluid relieved from the brake in an anti-lock mode. The solenoid-operated valve determines the pressure in a control chamber, a poppet valve controls communication between the master cylinder and the brake, and a restricted connection is provided between the master cylinder and the output from a re-application pump.

Abstract: A securing device for a railway rail includes a fixing rod having a first end in the form of a spring head which bears on the shoe of the rail. The rod extends through a shim and has a second end is configured like a hook and is held in an anchoring sheath embedded in a support. The anchoring sheath includes a shoulder for tensioning the spring head under the shoe of the rail after the rod has been rotated by a half turn. The tensioning of the rod also results from the slope of the upper surface of the shim which extends upwardly and continues the slope of the shoe of the rail.

Abstract: In a reversing device for movable parts of a railway switch within the deflection area of a railway switch, in particular tongue rails, monorail deflection device or movable stock rails, in which device the movable rails can be caused to contact rigid switch parts, the movable rails are supported in their contacting position by supporting rods extending in the longitudinal direction of the rail the supporting rods are slideably guided on the sleepers or, respectively, base plates in the longitudinal direction of the rails. In this case, the supporting rods are designed as adjusting members for the reversing operation and comprise thrust supports cooperating with thrust supports of the movable rails for shifting the rails. At least one of the mutually cooperating surfaces of the thrust supports of rail and/or of supporting rod is formed of a wedge surface passing over into a supporting surface extending in an essentially parallel relation to the longitudinal direction of the supporting rod.

Abstract: A brake system is provided so that the direction of delivery of a pump is reversible. This is advantageous in that, without any additional valves, the brake system can be used both for controlling a brake slip and for controlling a traction slip. The reversion of the direction of delivery of the pump can be achieved by changing the direction of rotation of the drive.

Abstract: An automatic method for preventing wheel skidding during braking and acceleration is disclosed, in which an instantaneous rotational wheel speed is sensed and an instantaneous absolute speed variation is calculated therefrom. During braking, the brake is released automatically when rotational speed either reduces so that speed variation is greater than a predetermined maximum permissible value, or when rotational speed approaches zero with the vehicle still moving. The brake is applied during braking when rotational speed increases to a predetermined time-varying value after brake release. During acceleration, the brake is applied when rotational speed increases so that speed variation is greater than the aforementioned maximum permissible value, and is released when rotational speed falls to a predetermined time-varying value after the brake application. The brake remains unaffected when speed variation is less than the maximum permissible value.

Abstract: The present invention relates to a brake corrector subject to the load of a vehicle despite the possible variation in the height of the seating of the latter. According to the invention, the corrector comprises a fluidic pressure sensor arranged between the vehicle chassis and the corresponding end of a suspension spring of the vehicle, a body (1) in which a slidably mounted at least one piston (2, 3) controlled by an actuating rod (10) and arranged so as to interact with a valve element in order to control a passage of the corrector, the body and the fluidic sensor being connected fluidically in such a way that a variation in pressure determines a first force exerted on the piston, and a sensor of the height of seating of the vehicle, the response of which determines a second force likewise exerted on the piston, the first and second forces combining to act on the piston (2, 3).

Abstract: An automobile brake system includes a master cylinder, a wheel cylinder and a solenoid actuated valve between the master cylinder and the wheel cylinder. The solenoid actuated valve is actuatable for maintaining high fluid pressure in the wheel cylinder after a brake pedal associated with the master cylinder has been released in order to prevent unwanted rearward rolling movement of a vehicle once it has stopped.

Abstract: An anti-lock brake system for vehicles with an electronic system which regulates the braking pressure of a monitored wheel as a function of the wheel speed, so that locking is prevented. The system is designed so that each wheel has its own speed sensor, and both wheels of one axle are pressurized with pressure medium by means of a joint control valve controlled by the electronic system. This arrangement corresponds to that of a select-low regulation. To shorten the extended braking distance on roads with different traction on each side, which occurs with a select-low regulation, the control system is designed so that when a retard signal (-b) occurs, the electronic system does not switch as usual to "remove pressure", but, at least until the occurrence of a slip signal (.lambda.), the control valve is switched to the "maintain pressure" position.

Abstract: A hydraulic control valve for controlling the parking brakes of a vehicle hydraulic braking system having mechanically applied parking brakes which are released by hydraulic pressure includes a housing having a mechanically actuated control valve and a diverter assembly. When the vehicle is parked, the parking brakes are vented to reservoir and fluid from the vehicle hydraulic pump is communicated directly from the inlet of the valve to the return or drain port of the valve. When the brakes are released, communication between the spring brakes and reservoir pressure is cut off, and fluid communicated into the inlet is diverted to the diverter assembly, which builds pressure to a predetermined level which is communicated to the vehicle parking brakes to release the latter. When the predetermined pressure level is attained, the diverter assembly automatically opens to permit fluid to bypass the diverter assembly back to the return or drain port.

Abstract: A slip-controlled hydraulic brake system with improved operational reliability during the slip control phase of operation has a master cylinder having shortened overall axial length. The master cylinder includes a valve-opening mechanism of one central control valve supported on the bottom of the longitudinal bore of the master cylinder, and the valve-opening mechanism of another central control valve supported on the secondary piston wherein during a slip control action, in the presence of a predetermined travel of the pistons of the master cylinder, a force component is generated that increases the reliability of the opening of the central control valves.

Abstract: An anti-locking brake control system for a motor vehicle comprises wheel speed sensors for determining the speeds of the individual vehicle wheels, an evaluation circuit which receives the wheels speed signals and generates brake pressure control signals, and a brake pressure control device responsive to the brake pressure control signals for controlling the brake pressure applied to the wheels. The evaluation (processing) circuit includes a brake pressure control unit which operates in such a manner that, after brake pressure decays, the brake pressure is first increased in a timed build-up with reference to the brake pressure build-up in a preceding control cycle, and thereafter the brake pressure is further increased by a sequence of pulses until an instability is again detected.

Abstract: The invention relates to an outer point lock device for switchpoints, particularly on high-speed railways. This device comprises two point locks (1, 2) associated each with one of the blades (A1, A2) of the switchpoint. Each point lock comprises a box (3) secured to the corresponding stock-rail (C1, C2) and containing two slides (7, 8) parallel to each other. The slides are superposed on each other and slidably guided across the rails. The so-called lock-slide (8) is connected to the respective blade (A1, A2) and carries a lock member (17, 49) to become locked to the box (3) in the closed position of the blade (A1, A2). The lock slide is coupled to the other so-called drive-slide (7) through a coupling device (28, 29; 249, 307) automatically engageable or disengageable as a result of the overlap stroke of the drive-slide (7) with respect to the lock-slide (8). The drive-slides of the two point locks (1, 2) are connected to each other and to a drive or control rod (44).

Abstract: A modulator assembly for a vehicle braking system includes a valve means for isolating a master cylinder from a brake actuator when a wheel slip condition arises at a braked wheel. Pressure modifying means is provided in the form of a piston which is moved axially by rotation of a motor armature 11 via a screw threaded connection to modify the braking pressure to correct the slip condition. Axial movement of the armature 11 moves a valve stem axially to close the valve means.

Abstract: An anti-skid-controlled hydraulic brake system is described where the pressure medium, bled off from the wheel brakes for the purpose of pressure control, is replaced from a storage reservoir. The pressure medium will be delivered by a pump to the wheel brakes, and also into the master brake cylinder. As a result, during brake slip control, the volume requirements of the wheel brakes partially are met from the master brake cylinder. Directly involved is a pedal pulsation. So as to attenuate the pulsation, a throttling unit is inserted into the line between the pump and the master brake cylinder. A simple embodiment includes an orifice inserted between the pump and master brake cylinder.