Abstract: The invention relates to a hydrostatic steering device having a servomotor connectable to wheels to be steered. The travel limits of the servomotor are sensed with position sensors which function to operate a locking apparatus which mechanically prevents further turning of the steering wheel upon a travel limit being reached in either direction.

Abstract: Highway trailer for hauling cargo has air actuated brakes. Valve mounted on the trailer connected in the air line maintains brake-on air pressure in the line while trailer is parked. Valve has locking handle to inhibit trailer theft.

Abstract: A brake cylinder comprises a brake actuator device having a fluid operable piston and a coaxial adjoining hand brake operable device for axial actuation of a coaxial tubular push rod, there being a slack adjuster for selectively adjusting the retraction of the push rod. An actuating rod is connected to the piston and the actuating rod is selectively connected and disconnected from the internal periphery of the push rod by locking rollers selectively cooperating with a wedge shaped annulus disposed between the actuator rod and the inner periphery of the push rod. Slack adjustment is permitted by axial travel of the push rod beyond free travel limits as permitted by a friction sleeve connection between the outer periphery of the push rod and the brake cylinder housing. In a modification, the locking device is provided for a fluid spread brake cylinder that is adapted by levers to be connected to a conventional freight brake rigging to be used, for example, for hand brake applications.

Abstract: An anti-theft device, having application for preventing unauthorized operation of a vehicle, includes a moveable lock member biased toward the actuating member for the vehicle's parking brakes. An electric solenoid is energized along with the ignition system to retract the lock member and allow the parking brakes to be released. The preferred device also includes a timer apparatus that requires the parking brakes to be released according to a predetermined timing sequence in order to substantially prevent theft of the vehicle.

Abstract: This invention relates to a selectively operable control system for use on an automotive vehicle to insure that the brakes of the vehicle will be locked after the engine has been turned off so as to prevent the vehicle from being stolen. The system includes a valve with a bidirectional motor and a control circuit for bidirectionally energizing the motor. The valve is established in an open position for normal braking only when an electronic key is inserted in a receptacle, and in a closed anti-theft position having check valve characteristics when the key is not inserted.

Abstract: An anti-theft apparatus for vehicles includes a permanent magnetic attraction and retention element joined to a valve incorporated in the hydraulic return circuit of the braking system of an automobile. The magnetic attraction and retention element is controlled by a dual effect coil activated only by an electronic circuit set off by specific voltages acting as an electronic code. A valve, a seal, the magnetic retention element, the dual effect coil, and the electronic circuit are housed in a tamperproof container.

Abstract: An air brake safety and parking mechanism is provided in the form of an emergency braking system which operates automatically to set and latch the air brakes of a vehicle in a braking position whenever the air pressure of the service braking system of the vehicle drops below a predetermined threshold, and which may be set and released mechanically for parking purposes. The air brake safety mechanism of the invention includes an antifriction ball screw coupled to the air brake piston in the air brake chamber of the vehicle braking system, and extending along a selected axis into an air-tight housing which is mounted adjacent to the brake chamber. A ball nut is rotatably mounted in the housing in threaded relationship with the screw to permit linear movement of the screw in both directions along the selected axis so long as the nut is freely rotatable.

Abstract: An air brake safety and parking mechanism is provided in the form of an emergency braking system which operates automatically to set and latch the air brakes of a vehicle in a braking position whenever the air pressure of the service braking system of the vehicle drops below a pre-selected threshold, and which also can be set and released mechanically for parking purposes. The mechanism includes an aperatured latch through which an actuating rod for the air brakes of the vehicle extends and is freely slidable so long as the latch is in a first angular position, but which is engaged by the latch when the latch is in a second angular position to prevent movement of the rod in a direction which would release the brakes of the vehicle. A feature of the mechanism is that it can subsequently be released and then re-set so that the brake can be used for parking purposes, for example, for a trailer.

Abstract: When the ignition key of a vehicle is turned to the off position an electric motor drives a pump to pressurize the hydraulic brake system of the automobile and thereby automatically apply the brakes. When the ignition switch is later turned to another position the electric motor again drives the pump to release the pressure in the brake lines. Pressure sensitive switches close check valves and turn the pump motor off once the brake system has been engaged or disengaged.

Abstract: A brake control valve for an automobile includes a main body having first and second bores intersecting with each other; a ball valve member arranged in the first bore, and rolled by its weight when the automobile is facing upwardly on an inclined road-way; a valve seat arranged in the first bore, and engageable with the ball valve member to check brake fluid flow between a master cylinder and a wheel cylinder; and a cam shaft slidably fitted into the second bore and inter-connected to a clutch pedal, having a cam portion in a brake fluid passage. Areas of the cam shaft at both sides of the cam portion receiving fluid pressure are substantially equal to each other. The cam shaft is rotated round its axis with actuation of the clutch pedal to displace the ball valve member through the cam portion for opening and closing the valve seat when the automobile is facing upwardly on the inclined roadway.

Abstract: A combined fluid pressure operable running and parking vehicle brake device including an application piston responsive to fluid pressure for exerting a brake-applying force on a vehicle wheel through a brake shoe for effecting either a service or emergency application, a locking piston responsive to fluid pressure independently of the application piston, for locking the brake device in an application disposition when the vehicle is parked, and compressible springs placed under compression by actuation of the application piston for storing a compressive force available for providing the brake-applying force in the event of failure of fluid pressure when the vehicle is parked.

Abstract: A piston braking device for a hydraulic or pneumatic cylinder, employing an annular braking plate loosely fitted on the piston rod of the cylinder and rockable into a tilted position relative to the piston rod upon actuation by a plate drive means, and a brake control mechanism operative to apply a counter pressure on the braking plate to maintain or reset the braking plate in a normal right angle position, the braking plate having braking portions on its inner periphery which braking portions are pressed against the circumference of the piston rod to apply friction brakes thereto in a manner which increases the braking force in proportion to the propelling force of the piston rod.

Abstract: A vehicle anti-theft device which is mounted on or in the instrument panel of said vehicle and which is connected into the brake fluid line that extends from the master cylinder to the brake wheel cylinders. By closing the valve while the vehicle brake pedal is depressed, fluid under pressure is trapped between the anti-theft device and the wheel brake cylinders, locking the wheels. The closed valve prevents reverse flow of the pressurized braking fluid until an authorized person in possession of the proper dial symbol to reference mark combination once again manually reorientates the set of dials that are attached to a plurality of cylinder valve port tubes and one spool that are rotated in proper sequence to bring all the tube ports in alignment with the casing ports.

Abstract: A parking brake for use primarily on railway vehicles of the mass transit type in conjunction with the service brake apparatus but operable independently thereof. A parking brake hydraulic cylinder is mechanically connected to the brake shoe hanger of the brake unit. After the vehicle has been brought to a stop, a parking brake application may be made by supplying pressure, by a handpump, to the hydraulic cylinder which also includes a lock-nut actuable by the pressure, in excess of a certain pressure for locking the parking brake hydraulic cylinder in its applied position. A relief valve is provided for relieving the hydraulic cylinder of hydraulic pressure when the application is to be released.

Abstract: A hydraulic handbrake control system for vehicles has a hand operable reversible fluid pump and a shuttle valve operable to circulate fluid in one direction for applying vehicle handbrakes, and in another direction for releasing vehicle handbrakes by governing flow of fluid alternately in application and release directions over application and lock release passages connected to a plurality of hydraulic handbrake cylinders. An improved lock control mechanism is associated with each of the cylinders having a check valve permitting passage of fluid from the application passage to the associated brake cylinder, but preventing release of fluid when handbrakes are applied.

Abstract: A brake cylinder device including a brake piston operable by a spring force to an application position and to a release position in response to an opposing fluid pressure force, and a fluid pressure operable locking device operable responsively to release pressure for locking the piston in the release position and for delaying such locking of the piston in the release position during normal operations to prevent untimely locking-up of the piston.

Abstract: A vehicle anti-theft device which maintains the braking function of the braking fluid by preventing reverse flow thereof from the wheel cylinder back to the master cylinder until, following an authorized procedure, an interconnecting fluid passage is moved into a strategic position which allows this reverse flow. As an improvement over the prior art, the direction of application of the braking fluid is arranged to assist, rather than impede, the strategic positioning of the aforesaid interconnecting fluid passages as well as contribute to other noteworthy advantages in the operation of the within device.

Abstract: A vehicle anti-theft device which maintains the braking function of the braking fluid by preventing reverse flow thereof through a closed main valve opening from the wheel cylinder back to the master cylinder until, following an authorized procedure, the main valve opening is cleared. As an improvement over the prior art, the main valve opening is closed manually by a member being seated therein, and this member is then held in place under pressure, the member, however, having an internal pressure-releasing valve for releasing the "holding pressure" when it is necessary to move the member into a clearance position off of the valve opening.

Abstract: A brake cylinder device including a conventional release piston spring-biased toward a full-application or emergency application position and operable responsively to fluid pressure applied thereto in opposing relation to the spring force acting thereon, to a brake release position, a conventional service application piston, both pistons being subjectable concurrently to fluid pressure for operating the release piston to its release position and the service piston to a service brake application position in accordance with the degree of fluid pressure acting thereon, and a locking mechanism for automatically locking the release piston in its release position upon attainment of a full service application and thereafter during service braking operation at less than full service level and while the vehicle is in motion, and being operable for unlocking the release piston upon stopping of the vehicle and withdrawal of service braking fluid pressure.

Abstract: For use, for example, in an anti-theft device having a lock, a piston moves in a cylinder having variant bores which provide upper and lower tapers. During factory assembly, a soft metal liner is deformed upon such tapers whereby to prevent, during later operational use, unwanted leakage of a pressure fluid either within or to the outside of the piston-cylinder assembly.

Abstract: A locking device for a reciprocating rod brake actuator movable between brake applying and brake releasing positions includes a pivoted pawl movable between locking and releasing positions for releasably locking the rod in its brake applying position. A spring normally biases the pawl to its locking position, and a fluid cylinder is operative when pressurized for moving the locking device to its releasing position. The rod is movable toward and away from the pawl, and is normally supported against movement away from the pawl by a releasable support. Release of the support frees the rod for free movement between its brake applying and releasing positions even though the pawl is in its locking position.

Abstract: A control valve for selectively establishing connections between the spring applied parking brake in an air braked vehicle and either the parking brake air reservoir or the exhaust port of the control valve, and incorporating a lock which enables the operator to secure the control valve in the position in which the parking brakes are applied.

Abstract: A disc or drum brake fluid pressure actuator incorporates a lock actuator strut acting on an inner part of a telescopic piston assembly, of which the inner and outer parts are normally rendered effectively unitary by pre-stressed spring which can, however, deflect under excess pressure to permit extension of the lock actuator strut when it is desired to operate the strut for parking purposes. An hydraulic control system for operating the actuator is also described and illustrated.

Abstract: A manually operable open-close valve remotely operated from the dashboard of a vehicle cooperates with the hydraulically controlled braking system of a vehicle having brakes on front and rear wheels to either block flow of hydraulic fluid to the front wheels or to permit normal flow.

Abstract: A motor vehicle security system for trucks, trailers and the like equipped with conventional fluid operated braking assemblies. The security system comprises a manually operable valve for controlling the application of fluid under pressure to the braking assemblies to manually set the vehicle brakes. The valve is arranged with a mechanical, key-operated lock for controlling and locking the valve in a selected position. When the valve is in a "locked" position it allows the brakes to be set and the vehicle maintained in situ to prevent the unauthorized movement thereof. The brake assemblies are also secured and locked to prevent the manual operation thereof by use of a conventional lockout tool.

Abstract: A hydraulic brake actuating and locking device is provided for applying brakes of a vehicle comprising an elongated brake cylinder having a tubular push rod axially operable therein for actuating the brakes and a hydraulically controlled locking device disposed within the tubular push rod and operable when rendered effective for acting on the inner periphery of the push rod to restrain the push rod against axial movement relative to the brake cylinder. The locking device is selectively actuated in accordance with the movement of a locking wedge within the push rod by a hydraulically operated locking piston.

Abstract: A brake system having spring applied fluid pressure released brakes is provided with an auxiliary source of pressure for release of the brakes and a valve that is locked into an inoperative position effective to thereby render it tamper-proof.

Abstract: A brake system for a wheeled carrier having manually operable apparatus for actuating and locking parking brakes at the wheels, the system including automatically operable apparatus for ensuring release of the manually operable parking brakes when it is desired to move the vehicle.

Abstract: A brake locking mechanism for heavy vehicles, adapted to be installed in existing braking systems without altering the normal operation thereof, functions to prevent involuntary movement of the vehicle, due to system failure such as air or hydraulic fluid leakage, while standing. The mechanism includes a spring biased pawl engageable with rack teeth formed on the diaphragm actuated brake rod, the pawl being operated by an air or hydraulically actuated piston associated therewith and connected into the vehicle air or hydraulic system.