Abstract: A control system (10) for a spring applied, pressure released brake (16) is provided to control the pressure level in the brake (16) in response to operation of a control valve (22) to stage the pressure levels relative to the operating mode of the control valve. The control system (10) also provides two different fluid pathways (58,60) that are individually operational to lubricate a winch and draw-works mechanism (18) in response to the operating position of the control valve (22). This system improves the response time needed to gradually release the brake (18).

Abstract: This invention relates to a brake control system (10) for controlling engagement and disengagement of a spring applied pressure released brake (11) of a winch and includes an orifice (39) and a relief valve (37) connected in series to the outlet port of a metering pump (23) to relieve pressure in the outlet port at a lower than normal pressure level when the fluid flow therethrough is below a predetermined flow rate. Relieving the pressure at the outlet port of the metering pump reduces the pressure differential between the inlet port (24) and outlet port (26) of the metering pump and thereby drastically reduces the internal leakage within the metering pump so that the metering pump is operative to pump fluid from the actuating chamber (14) at the slow rotational speeds of the rotatable member (12).

Abstract: A brake control for a vehicle, especially a heavy work vehicle, having both service and emergency braking systems, each system having its own hydraulic actuator, having a fluid reservoir, a hydraulic pump and a manually actuable control valve wherein the control valve includes a variable pressure regulating portion having an inlet from the pump, an outlet to the service brakes and a spool controlling the outlet pressure to the service brakes. The control valve also has a three-way valve portion having an inlet from the pump and an outlet to the emergency brake actuators, preferably the pressure-release, spring-apply type, and an externally controlled valve stem with a wide groove which supplies pressure to the emergency brake actuators continually over much of its travel while operating the service brake portion through a compression spring disposed between the stem and the spool.

Abstract: An auxiliary release apparatus for use with a hydraulic pressure releasable brake having a principal source of hydraulic pressure which comprises an auxiliary source of hydraulic pressure selectively connectible to the brake for releasing the brake when the principal source of hydraulic pressure is not operating. The auxiliary release apparatus includes a manual pump device for interrupting communication between the normal pressure source and the pressure releasable brake when the pressure source, as a pump, is not operating, and for manually pumping through a by-pass circuit pressure fluid to the pressure releasable brake.

Abstract: A shut-off cylinder for use in a hydraulic braking system comprising a cylindrical housing, an inlet end cap and an outlet end cap received and secured in the open ends of the housing, the inlet end cap having an inlet port in fluid communication with the interior of the housing and connected to an inflow source of hydraulic fluid from a hydraulic reservoir of the braking system, the outlet end cap having an outlet port in fluid communication with the interior of the housing and connected at its output end to an outflow source of hydraulic fluid to the braking system, a piston slidably received in the interior of the housing between the inlet end cap and the outlet end cap, a coil spring received in the space between the piston and the outlet end cap biasing the movement of the piston under normal operating conditions against the pressure of the inflow source, a by-pass tube communicating with the inlet and outlet ports of the housing, a valve for opening and closing communication between the by-pass tube and

Abstract: A hydraulic emergency braking system for a vehicle also having service brakes wherein a hydraulic directional control valve provides input pressure to a dump valve having a pressure outlet to spring apply, pressure-release brake actuators and a dumping outlet to the hydraulic reservoir. Internal conduits in the dump valve housing assure continuous transmission of inlet pressure to the pressure outlet thereby releasing the pressure-release brakes, while preventing reverse flow with a check valve when the directional control valve dumps the inlet pressure to the reservoir to apply the brakes. In the absence of inlet pressure to the dump valve, a spring-biased spool valve connects the pressure outlet to the dumping outlet, thereby immediately dropping the pressure in the brake actuators to the value predetermined by the spring.

Abstract: An air brake system augments the braking force available while parking without interfering with the operation of the parking brakes. The brake system includes a service brake, a pilot check valve and, typically, a quick release valve. The quick release valve and pilot check valve are interconnected in two alternative ways among the service and spring brake lines and the service brake cylinder. When the spring brake line is pressurized the system acts normally. However, when the pressure on the spring brake line is eliminated the pilot check and quick release valves trap the pressurized air within the service brake. This keeps the service brake for each individual wheel actuated. Pressurizing the service brake line pressurizes the service brake regardless of the condition of the spring brake line. Safety valves can be incorporated in the brake systems to insure that the pressure within the service brake chamber does not exceed a predetermined value.

Abstract: A brake system for a vehicle having a pair of brakes each being spring-applied and hydraulically released. A two-position brake valve is disposed between a source of fluid and the brakes. At normal position, the brake valve allows to connect the brakes to a tank thereby applying the brakes while at an offset position fluid is introduced into the brakes so as to release them.The brake valve is operated either by an electric actuator such as stepping cylinder or introducing fluid into a pilot port through a solenoid-operated valve. The electric actuator is operated in accordance with a signal from a potentiometer which in turn is operated by the movement of a brake pedal. The solenoid-operated valve is actuated by a signal from a switch which is adapted to be switched on by a brake lever for parking and emergency braking.

Abstract: Apparatus (1) for automatically releasing a railroad car hand brake (HB) normally maintained in its applied position. An air pressure activated cylinder (9) acts on a hand brake release (5) to release the hand brake. An air line (13) directs pressurized air from a pressurized air source to the air cylinder. A valve (27) connected in the air line is responsive to the source air pressure. The valve is normally closed but opens when source air pressure reaches a level sufficient to release the air brakes on the car. A draft load sensor (29) is positioned in the air line between the valve and air cylinder. The sensor normally blocks the air line, but unblocks it when a sufficiently great draft load is sensed. The hand brake is released only if source air pressure is sufficiently high and the draft load on the railroad car is sufficiently great.

Abstract: Apparatus (1) for automatically releasing a railroad car hand brake (HB) normally maintained in its applied position. An air pressure activated piston (11) acts on a hand brake release (5) to release the hand brake. An air conduit (13) directs pressurized air from a pressurized air source to the air cylinder. A normally closed first valve (25) is connected in the air conduit between the source and the air cylinder. A normally closed second valve (29) is connected in the air conduit between the source and a control inlet of the first valve. A sensor (33) senses an inertial load on the car and opens the second valve when the inertial load sensed exceeds a predetermined acceleration factor. Air pressure directed to the control inlet of the first valve through the second valve, when it is open, opens the first valve if the air pressure level is sufficiently great to release the air brakes of the car.

Abstract: A standard motor vehicle having a pair of driving wheels (8), (9) powered by a drive shaft (10) through a differential (11) can experience difficulties when one of the two differentially driven wheels (8/9) loses traction. The differential (11) directs all of the power to the wheel that is slipping and the wheel with traction remains stationary. Various anti-spin devices have been developed but these often produce an abrupt transfer of all of the driving power to the wheel having traction. The anti-spin apparatus of this invention overcomes this problem and includes an electrical control circuit (24) and sensors (20), (21) for generating a slip signal representing the speed difference between the wheels (8), (9). The apparatus further includes a modulated hydraulic reducing valve (30), (110) for actuating the brake (15/15') on the faster rotating wheel (8/9) and a hydraulic modulating control valve (29) connected to the reducing valve (30), (110) and actuated by the slip signal.

Abstract: A vehicle brake system for operating a spring applied, fluid pressure released brake. In order to assure that the brake is fully released before the vehicle is operated, the system requires the operator to perform two operations. He must move a manually operated hydraulic valve to the brake release position and in addition must close a normally open, momentary contact switch which actuates a second solenoid operated valve in series with the first valve to the brake release position. When pressure has built up in the brake actuator sufficiently to assure that it is fully released, a pressure sensor causes a hold-in circuit for the solenoid operated valve to be energized whereupon the operator can then release the momentary contact switch.

Abstract: A braking system for a tractor-trailer combination vehicle having air brakes includes a two plunger control valve in which one of the plungers controls the brakes on the tractor and the other plunger controls the brakes on the trailer. However, the valve is designed such that actuation of the plunger controlling the brakes on the tractor to a condition effecting an application of the spring brakes on the tractor automatically actuates the other plunger to effect an automatic actuation of the spring brakes on the trailer. Operation of the plunger controlling the trailer brakes is independent of the plunger controlling the tractor brakes, so that application of the trailer spring brakes may be effected without applying the tractor spring brakes. The tractor spring brakes may be released with the trailer brakes applied to permit bobtail tractor operation or permit the trailer to be parked with the tractor spring brakes released.

Abstract: A vehicle (10) having an operator's cab (12) which may be tilted to gain access to parts of the vehicle located beneath the cab, has a braking mechanism which automatically brakes the vehicle (10) when the cab (12) is tilted so that maintenance and tests may be conveniently performed on the components under the cab (12) while the engine is running. The mechanism consists of a pedal (34) and a linkage (40,44,48) carried by the cab (12). The linkage includes a lever arm (40), a rod (44) and a lever arm (48) connected to a brake actuating assembly. The pedal (34) and linkage are operated to activate the brake actuating assembly for conventional braking and are carried with the cab (12) during tilting of the cab to automatically activate the brake actuating assembly to set the brakes.

Abstract: An emergency brake system for mine shuttle cars and the like wherein the brakes are applied by spring pressure and are normally released only when the hydraulic system for the shuttle car is activated. In the present invention, a hand pump is provided for releasing the brakes when the normal hydraulic system is not activated. This facilitates moving the shuttle car when it is not connected to a source of power. When the car is again connected to a power source and its hydraulic system activated, a shuttle valve initially releases the pressure produced by the hand pump and then returns the system to normal operation.

Abstract: A brake system for a vehicle having spring applied, pressure releasable brakes (10) including a manual pump (28), a terminal board (14) having ports (16,18,20) terminating the system fluid pressure line (22), the brake pressure line (12) and the pump pressure line (76), and a U-tube (120) connecting two of the ports on the terminal board. In the alternative embodiment, an emergency brake release system for a vehicle having spring applied, pressure releasable brake (130) including a pump (166), and a control valve (140) for selectively connecting the pump (166) to the brakes (130) while connecting the fluid pressure supply line (133) to a reservoir return line (136). The valve (140) includes modes for connecting the brakes (130) to the supply line (134) through an orifice (192), and a brake outlet line (138) to the reservoir return line (136) for bleeding the brakes (130), and for isolating the supply line (134) while venting the brake line (133), for checking system pressure.

Abstract: Three embodiments of a hydraulic braking system are shown and described. Each embodiment provides a precisely controlled hydraulic braking system for a railway vehicle, which features a pilot pressure controlled brake control valve. The pilot pressure is selectively varied by operation of pressure control and flow control valves so that the power requirements for the hydraulic braking system are minimized. The braking system can be used with either spring-apply, pressure-release or pressure-apply, spring-release braking actuators. An auxiliary hydraulic system is provided to operate the brakes if the primary hydraulic system should fail. The pilot pressure fluid which operates the brake control valve can be either hydraulic or pneumatic. The brake control valve can be provided with a pneumatic emergency brake override control.

Abstract: The present invention is a pulse valve which imparts a force to a piston means for a limited duration of time or over a given distance. This pulse valve can be incorporated into a manual control valve. The manual control valve is particularly useful in an air parking brake control system for an air parking brake system.

Abstract: PCT No. PCT/US79/00597 Sec. 371 Date Aug. 13, 1979 Sec. 102(e) Date Aug. 13, 1979 PCT Filed Aug. 13, 1979 PCT Pub. No. WO81/00384 PCT Pub. Date Feb. 19, 1981A hydraulic fluid brake system having a differential lock causes all of the torque from the engine to be delivered to the non-spinning wheel resulting in overloading of the components. By providing a non-locking differential (54) and a hydraulic fluid brake system (10), a controlled braking of the spinning wheel will provide a torque to the non-spinning wheel substantially equal to the torque from the braking of the spinning wheel and not allow the spinning wheel to be fully braked. The operator can selectively move a valve member (26) and maintain a modulated source of pressure (20) to the non-spinning wheel and controllably modulate the fluid pressure at the spinning wheel, thus controlling the braking effect of the brake on the spinning wheel. This arrangement controls the torque and eliminates harsh braking of an individual wheel.

Abstract: A braking apparatus for vehicles has a switching device which controls the admission of pressure fluid to the braking cylinder of a service brake and is operated by a reaction force acting upon a coupling or bearing support between the switching device and a lever operatively connected to a parking or locking brake. When this reaction force exceeds a predetermined limit upon operation of the parking brake, the switching device is actuated to release the service brake. The service brake is released at that time when the parking brake already applies a braking force and the short period of time between the parking brake being locked and prior to release of the service brake is so short that the brake linkage of the service brake is not subjected to any damaging effects.

Abstract: A control for a spring-apply, pressure release brake system having a pilot signal-generating valve and a slave brake valve interconnected by a pilot signal line. Hydraulic pressure is directed to both the pilot valve and the slave valve. Manual stroking of the pilot valve modulates the pressure to the signal line. A spool within the slave valve senses both the signal pressure and the brake pressure and moves to an equilibrium position to equalize the signal and brake pressures.

Abstract: PCT No. PCT/US79/00598 Sec. 371 Date Aug. 13, 1979 Sec. 102(e) Date Aug. 13, 1979 PCT Filed Aug. 13, 1979Conventional fluid control circuits for brakes and the like normally comprise a control valve interconnected between a pressurized fluid source and the brakes for selectively actuating the same. A problem arises in that upon starting of the vehicle during cold weather conditions, the hydraulic fluid is not sufficiently warm to ensure efficient brake operation. This invention includes conduits (36) for sequentially communicating fluid from a fluid source (11), through an actuating chamber (14) of a brake (15), and to a control valve (25) in series when the brake (15) is either in its disengaged or engaged condition of operation. Furthermore, upon actuation of the valve (25), an operator is enabled to detect by "feel" the degree of brake engagement.

Abstract: A vehicle braking system incorporating two circuits serving driven and non-driven axles respectively and in which both air-actuated service brake units and spring brake units for parking are provided on both axles. The system includes relay valving which is operable upon failure of the service braking in either circuit and responsive to the service pressure in the other circuit to provide a graduated actuation of the spring brake units in the circuit where service braking has failed. The spring brake on the driven axle and/or the relay valving is so constructed as to attenuate the force applied by the spring brake units on the driven axle.

Abstract: A two knob control for tractor and trailer parking brakes providing single knob application of both tractor and trailer parking brakes. It also provides for maintaining the tractor parking brakes in the applied condition while charging the trailer brake air system and for applying the trailer brakes independently of the tractor brakes. Automatic application of trailer parking brakes is provided upon trailer breakaway or a significant reduction in tractor reservoir air pressure.

Abstract: In a hydraulic brake system which combines a spring actuated, hydraulically released parking brake system with a hydraulically actuated service brake system and in which the parking and service brake systems both operate through a common force-transmitting element on the brakes, and in which the fluids in the two brake systems are mutually incompatible, an anti-compounding valve limits the sum of the forces which can be transmitted by the common force-transmitting element when the service and parking brake systems are simultaneously applied and which maintains the fluid in the two brake systems isolated from each other.

Abstract: A fluid pressure braking system for the trailer portion of a tractor-trailer combination vehicle includes valving mechanism which permits the vehicle spring applied, fluid pressure released parking brakes to be released after a single brake system failure. The system requires a pair of fluid pressure reservoirs, and includes the necessary interlock to permit both of the reservoirs to be charged while protecting the reservoirs in case of a leak in the system. The system also permits the vehicle parking brakes to be charged with the fluid pressure stored in either of the reservoirs. Both of the reservoirs normally provide the fluid pressure to actuate the vehicle service brakes.

Abstract: A safety-brake control system for a vehicle for the automatic actuation of the parking-brake valve to the brake-applied position comprising a lever arm connected at one end to the actuator of the valve and at the other end to a flexible connector element which in turn is connected to the moving arm of a solenoid. Energization of the solenoid pulls the flexible connector element to move the lever arm to actuate the valve to the brake-applied position. The valve thereafter can be actuated to the brake-released position by manual movement of the valve actuator.

Abstract: A time division switching regulator wherein a single power source is connected to a plurality of inverters the outputs from which are rectified and smoothed and appear at respective output terminals, and the output voltages at said terminals are sequentially monitored and are compared with a reference voltage to generate an error signal in response to which the output from the corresponding inverter may be controlled or regulated.

Abstract: A fluid pressure braking system for an articulated vehicle includes a pair of manually operated, push-pull control valves and a pressure differential responsive dual supply valve. The inlet of one of the manually operated valves is connected to the fluid pressure source, and the outlet is connected to the parking brakes on the power portion of the articulated vehicle and also to one inlet of the dual supply valve. Another inlet of the dual supply valve is connected directly to the fluid pressure source. The outlet of the dual supply valve is connected to the inlet of the second manually operated control valve, the outlet of which is connected to the parking brakes on the towed or nonpowered portion of the articulated vehicle. Application of the spring brakes on both portions of the vehicle is effected by actuation of one of the valves, but release of the spring brakes on both portions of the vehicle requires actuation of both of the manually operated valves.

Abstract: A parking brake control valve for a vehicle fluid pressure braking system is actuable by the vehicle operator to control communication from a fluid pressure source to supply hold-off pressure to the vehicle parking brakes. The parking brakes are of the spring applied, fluid pressure released type, in which the spring actuator automatically effects a mechanical brake operation when hold-off pressure drops below a predetermined level. The parking brake control valve is responsive to a supply pressure below a predetermined level to automatically vent the hold-off pressure from the parking brakes, but this predetermined low pressure is less than the value of the spring brake hold-off pressure below which the brakes are gradually applied or "drag".

Abstract: A vehicle braking system has a spring engaged and fluid released drive line brake, a pair of fluid engaged and spring released service brakes, and a control circuit for applying only the service brakes over a preselected braking force range and for applying the service brakes and the drive line brake in response to a braking force greater than said preselected range. The control circuit preferably includes an inverter valve, and also an override valve for selectively applying the drive line brake independently of the operation of the service brakes.

Abstract: An auxiliary release apparatus for use with a hydraulic pressure releasable brake having a principal source of hydraulic pressure comprises an auxiliary source of hydraulic pressure selectively connectable to the brake for releasing the brake when the principal source of hydraulic pressure is not operating. The auxiliary release apparatus includes a shuttle valve and a relief valve for automatically disconnecting the auxiliary source and reconnecting the principal source of hydraulic pressure from the brake when the principal source of hydraulic pressure is operating. The auxiliary source of hydraulic pressure includes a cylinder, a hand pump comprising a handle and a piston connected to the handle and disposed in the cylinder, a fluid supply reservoir and suitable connection lines between the fluid supply and the cylinder. The relief valve also regulates the amount of pressure provided to the brake by the hand pump.

Abstract: An annular single piston brake arrangement is disclosed for selective holding engagement of a rotatable member of a drive train. The brake arrangement includes a support structure, an annular brake piston axially reciprocably and nonrotatably mounted within the support structure, a plurality of springs mounted intermediate the support structure and the brake piston for biasing it concentrically toward peripheral brake holding engagement of the rotatable member, a fluid retractor for holding the brake piston in a disengaged condition overcomingly against the action of the springs, and a fluid actuator for biasing the brake piston concentrically towards peripheral brake holding engagement of the rotatable member.

Abstract: A tractor-trailer parking control valve includes a spring-biased valve member movable within a chamber to control communication between a spring brake chamber port and an exhaust port and the spring brake chamber port and a source of fluid pressure. In a second chamber within the control valve housing is a two-way check valve which controls the supply of pressure from one of two reservoirs to the chamber of the spring-biased valve member.

Abstract: Back pressure from the hydraulic power brake assembly of a vehicle acts on brake actuators to hold off spring apply brake assemblies through a vehicle operator actuated control valve. When the parking brakes are to be actuated, the operator turns the control valve so that it vents the hydraulic hold-off chambers to the hydraulic power brake sump, permitting the springs to apply the parking brakes. The hydraulic service brake system includes pistons in the brake actuators for normally actuating the brakes under pressure generated by the hydraulic power brake assembly. The pistons are mechanically acted upon by the spring apply forces when the parking brakes are actuated. The parking brake mode therefore uses the same wheel brake elements as does the service brake mode.

Abstract: A valve for controlling the operation of spring brake chambers in spring brake actuators used in tractor-trailer combinations. The valve is adapted for use with two spring brake actuators and two sources of supply pressure and includes an integral check valve for permitting fluid to flow from either source into the valve but from neither source into the other source. The valve further includes apparatus for alternately providing communication between output port(s) to the spring brake actuators and the check valve or an exhaust port.

Abstract: A brake mechanism includes a body and a piston movable relative thereto in braking and brake-releasing directions. A spring is disposed within a chamber defined by the body and piston to urge the piston in a brake-applying direction, and pressurized air may be selectively directed to such chamber to the piston in a brake-applying direction.

Abstract: This invention relates to a vehicle brake apparatus wherein a service brake application is effected by a spring in response to the reduction of the pressure of fluid in a first chamber on one side of a brake-applying piston, and an emergency brake application is effected by the establishment of a fluid pressure in a second chamber on the other side of this piston whereby this other side of the piston is subject simultaneously to both the fluid pressure force thus established and the force of the above-mentioned spring.

Abstract: A valve for use in applying brake releasing pressure to brake chambers in a vehicle air brake system having reservoirs each containing air for either service or emergency use and having air pressure supply lines. The valve includes a housing. A chamber is formed in the housing. A port permits air communication between the valve and a supply line. A passage interconnects the port and the chamber. Reservoir ports interconnect through the passage. A first plurality of one-way check valves in the passage permit air to pass therethrough from the port to the reservoir ports. A second plurality of one-way check valves in the passage permit air to pass therethrough from the reservoir ports to the chamber.

Abstract: A release mechanism for a normally applied, spring-loaded brake includes a valve manually operable by a control cable to direct pressurized fluid from a residual source to the brake to release it. The valve includes pump device whereby further operation of the control cable will pressurize residual fluid in the valve to release the brake if system fluid pressure is lost. The valve is below sump oil level so that it is always flooded with oil. This supplies fluid to the valve pump device during loss of system pressure and also allows for bleeding the brake release mechanism by siphoning action whenever the valve is operated.

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: A brake pressure modulating control valve for a hydraulically operated brake system. The control valve includes a spool associated with an air spring chamber. The system includes equipment for modulating the air pressure in the air chamber for constantly and concurrently modulating the pressure of the hydraulic fluid in the brake system.

Abstract: A fluid pressure braking system for a vehicle having brake actuators which may be mechanically held in the brake-applied position when the vehicle is parked and which may be actuated from either service or emergency actuating systems, is provided with a fluid communication limiting valve which limits fluid communication through the service actuating system to the brake actuators when the actuators have been actuated by the emergency system, thereby providing an "anti-compounding" capability so that the brake actuators cannot be actuated by the combined full capacities of both actuating systems. The system further includes a standby valve which is responsive to a normal brake application to communicate fluid pressure to the actuators through the emergency system when the failure of the primary fluid pressure system prevents communication to the actuators through the service system.

Abstract: A trailer air distribution valve has a housing, a chamber in the housing and an air inlet port, an exhaust port, at least one service tank port, an emergency tank port and at least one brake chamber port, all in communication with the chamber. A shuttle is movable within the chamber to control communication between the ports and includes a pair of spring biased valves functioning as check valves to control communication between the inlet port and service tank port and the emergency tank port.

Abstract: A fluid pressure braking system for an articulated vehicle wherein the system includes a supply line and a service brake line interconnecting the tractor and trailer portions of the vehicle. A trailer control valve controls communication through the service brake line. A throttle valve is located in the supply line, and is adapted to restrict communication therethrough when the pressure differential across the trailer control valve exceeds a predetermined level during a brake application.

Abstract: An emergency brake system is provided for a vehicle having separate fluid operated front and rear wheel service brakes and a control system with separate front and rear fluid conduits for individually conducting pressurized fluid to effect the application of the service brakes. The emergency brake system includes an emergency brake and a pressure differential detecting device connected to each of the fluid conduits for detecting a difference in the fluid pressures of the conduits. The detecting device is connected through apparatus to the emergency brake to effect the automatic application of the emergency brake when the service brakes are applied and the difference in the pressures of the conduits is beyond a predetermined value.

Abstract: A velocity rate change sensitive fluid valve wherein the valve is comprised of a pendulum member pivotally supported in a reservoir of fluid. The pendulum member is arranged to intercommunicate an input port and an output port with the fluid reservoir upon pendulous movement. The pendulum is supported by a fixed shaft which is ported along its axis to define fluid input and output passages. The pendulum member includes an intercommunicating passage which, upon displacement of the pendulum by a predetermined amount of rotation, as for example by an acceleration or deceleration, will intercommunicate the input and output passages of the support shaft. Fluid flow or fluid pressure may then be communicated through the valve as an acceleration or deceleration indicative signal.

Abstract: A braking system for the brake of a fluid motor including a jack for releasing the brake and two selectors for controlling the flow of working fluid to the jack. The first selector is responsive to the supply of fluid to the motor to place the jack in communication with a supply pipe and the second selector is responsive to pressure in a bleed pipe connected to the fluid supply to the motor to place the supply pipe in communication with a supply of working fluid under pressure.

Abstract: Braking system for use in track-type vehicles. The system includes a steering brake, a brake cylinder in which an emergency brake piston and a spring for biassing the emergency brake piston to its braking position are provided. The emergency brake piston is operatively connected to the steering brake through a link mechanism and defines with the braking cylinder a hydraulic pressure receiving chamber connected to a hydraulic fluid supply source to maintain the emergency brake piston in its non-braking position against a biassing action of the spring in case of the normal condition of the vehicle. The link mechanism comes into contact with an auxiliary lever serving to move the emergency brake piston to its non-braking position.

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.