Abstract: A hydraulic brake control device has a load sensing component connected through an electric circuit to a motorized proportioning valve which loads or unloads a resilient member therein to vary the split point of the proportioning valve. The electric circuit has an attitude cutoff switch and a speed cutoff switch which deactuate the electric circuit when the vehicle is pitched or rolled above a predetermined horizontal attitude and moving faster than a predetermined speed, respectively. The electric circuit can either actuate the motor to load the resilient member within proportioning valve, unload the resilient member within proportioning valve, or render the motor inactive and maintain the proportioning valve in a status quo condition.

Abstract: A hydraulic braking system is provided for vehicles which frequently experience variable loading conditions ranging from maximum to near minimum gross vehicle weights. The system comprises dual proportioning valves, hydraulically in series with one another, one valve includes a unique spring driven digital cam which, in response to compression of the vehicle suspension system, selects the desired master cylinder to brake pressure relationship for the vehicle load condition.

Abstract: A brake system for motor cycles is disclosed which includes a hydraulic master cylinder supplying a front brake and a rear brake and a pressure-regulating valve having a calibrating spring adapted to limit the maximum pressure on the rear brake to a predetermined value. The compression of the calibrating spring of the pressure-regulating valve is controlled by the relative motion of two distinct points on the rear shock spring.

Abstract: A power cylinder unit, adapted for use in truck mounted, self-aligning railway freight car tread brakes comprises a housing, a bulkhead which seals the housing, and a rigid, but moveable piston rod. The housing includes an annular bearing adapted to provide lateral support for piston rod and a spring which urges the piston toward the bulkhead. The combination of the housing, the bulkhead and the piston head define a gas-tight space to which the brake operating compressed air is passed. The piston head includes three circumferential grooves adapted to receive a bearing ring, a fluid sealing ring and a lubricating ring. The cylinder may be eccentrically mounted.

Abstract: Dual-circuit brake force control systems are known in which the initial preloading force is changeable dependent on the vehicle load. The initial preloading force is distributed to the control pistons by a lever. Due to manufacturing tolerances and erosion of the individual elements, considerable differences in pressure in both brake circuits may occur. Therefore, according to the instant invention a control lever is provided to directly actuate both control pistons and which is rotatable about an axis perpendicular to the axes of the control pistons and also rotatable about the longitudinal axis of the lever. A holding member shaped like a ball bearing enables the lever to rotate about these two axes. Adjustable stops are provided which cooperate with circular stop surfaces extending from the lever on opposite sides of the longitudinal axis with the center of the stop surfaces being disposed in a plane parallel to the longitudinal axes of the control piston and containing the axes of the control piston.

Abstract: A load-controlled brake pressure control unit for vehicle trailers including a load-weighing portion for operating a pressure control valve portion for effecting supply of brake-applying pressure via a relay valve according to vehicle load, a connection whereby brake-applying pressure is simultaneously supplied to the trailer brakes, and an emergency valve portion for effecting an emergency application in the event of separation or rupture of the trailer brake connecting line, all of the portions and components being housed in one casing.

Abstract: A load conscious control valve arrangement for modifying the pressure applied to the rear hydraulic brake of a motor cycle comprises a control valve rigidly mounted by a bracket on the frame of the motor cycle. The stem of the control valve is connected by a tension spring to an adjustable spring support of a combined spring/damper suspension strut. Deflection of the rear suspension as a result of increased loading causes an increased tension to be applied by the spring and thereby increases rear brake pressure. To compensate against the decrease in tension which would otherwise be applied to the valve stem when the adjustable stop is adjusted but there is no increase in the load on the motor cycle, an eccentric formed on the adjustable stop so that rotation of the stop may be provided to adjust the suspension strut causes a shift in the radial direction of the suspension strut of the point Z at which the spring is connected to the spring support.

Abstract: An empty and load brake device for a railroad vehicle air brake system includes an air pressure source, a control valve, a proportional valve and a brake cylinder all connected in series. A load sensor valve is in fluid communication with the line between the proportional valve and the brake cylinder. If the sensor valve senses an empty load condition, it actuates the proportional valve to decrease the air pressure supplied to the brake cylinder. The load sensor valve has a rock and roll spring which dampens movement caused by rough track conditions, thereby preventing erroneous indications of either an empty or loaded car.

Abstract: A control valve is provided for use in brake applications in air-spring equipped railroad and highway vehicles, particularly convertible rail-highway semi-trailers. Such vehicles usually employ pneumatic brake cylinders. The control valve combines the functions of a relay valve with two distinct output limiting characteristics, namely, service and emergency, which output limiting characteristics depend upon vehicle weight is indicated by air spring pressure. The control valve also produces an automatic minimum output to prevent total loss of braking should air spring pressure be lost due to failure.

Abstract: Empty/load control valve apparatus is proposed for use with direct release triple valves which operate by switching in an extra volume with the brake cylinder for empty loaded conditions. This improvement provides a valve operated in response to leakage away of brake cylinder pressure to enable dissipation also of the extra volume pressure to prevent brake cylinder isolation resulting from the extra volume pressure.

Abstract: Twin brake force control units, for a two circuit brake system are known in which the initial control force is changeable dependent on the vehicle load. The control force is distributed to the control pistons by a lever. Due to tolerances and erosion of the individual elements considerable differences in pressure in both brake circuits may occur. This is overcome according to the present invention by providing a lever which directly operates upon both control pistons and which is rotatable about an axis perpendicular to the shifting movement of the control pistons and which is additionally rotatable about its longitudinal axis. This double rotation of the lever is accomplished by supporting the lever in a spherical joint.

Abstract: A vehicle load sensing arrangement comprises an input arrangement to which is applied the force of a road spring and a control valve which may, for example, be a pressure reducing valve, having a movable valve member. A control spring acts in opposition to the road spring and together with a force-reduction arrangement serves to reduce the road spring force so that only a proportion of the road spring force is applied to the valve member the remainder being applied to the sprung part of the vehicle. To reduce the load and size of the control spring, and to thereby reduce the required installation space, the control spring is arranged between the valve member and the force-reduction arrangement and acts against the force transmitted by the force-reduction arrangement, so that the effective force acting on the valve member is the difference between the proportion of the road spring force transmitted by the force-reduction arrangement and the force of the control spring.

Abstract: This invention relates to a change-over valve (or a so called empty-load valve), preferably for a railway vehicle, having a valve device opening or closing a pneumatic passageway depending on the position of a mechanical operating system or in other words the load on the vehicle.In order to improve the working range of the external operating arm and the exactness of the change-over point the operating system comprises a force transmitting chain from said operating arm to the valve device via a spring, a knee lever, and a valve operating rod structured in such a geometrical way that the axis of the spring is substantially perpendicular to the valve operating rod.

Abstract: In a variable load valve device of the type employing a walking beam type lever arrangement via which the control and compensating pistons are interconnected to obtain load-dependent control of the brake pressure, there is provided a screw adjustment that acts through an auxiliary piston to vary the tension of a bias spring acting on one of the levers of the lever arrangement to bias the compensating piston in order to withhold the load-dependent brake control until a predetermined level of brake pressure is developed. The auxiliary piston is subject to brake control pressure supplied to the variable load valve inlet and in one embodiment of the invention, the auxiliary piston is formed to urge the piston in a direction to counteract the spring force and in another embodiment, to urge the piston in a direction to supplement the spring force.

Abstract: A control mechanism is provided for a vehicle braking system of the kind in which a pair of pressure modulating valves have their performance modified during vehicle cornering only so that the brake on the inboard wheel receives less pressure than the brake on the outboard wheel. The control mechanism comprises a member which has four points forming the corners of a trapezium. The first two points, which are at the ends of one of the parallel sides of the trapezium, are connected to the suspension, the third point is connected to the valves, while the fourth point is constrained from vertical movement. During normal travel the member rotates freely about the third and fourth points so that there is no input to the valves. However, in cornering the vehicle roll causes the first and second points to move differently so that the third point also tends to move so altering the performance of the valves.

Abstract: The invention relates principally to vehicle fluid pressure braking systems in which valve devices controlled by the vehicle suspension system operate only during vehicle concerning to reduce pressure to the brake which is on a wheel which is on the inside of the corner.The braking system uses a variable ratio lever mechanism to balance the loadings due to pressure in two valve devices. The lever mechanism includes levers, control links, balance beam and a reaction link. A control mechanism, which can be of a known kind, moves the reaction link during vehicle cornering and thus alters the angle which each control link makes with a line joining the axes of the lever pivots and the link pivots.

Abstract: A vehicle drum brake has a shoe mounted on a back plate, one end of the shoe engaging an actuator and the other end engaging an abutment. To avoid the use of a fluid pressure control valve to vary the braking effort of the brake in dependence upon vehicle loading, the abutment is in the form of a roller which engages an arcuate member on the shoe, the roller being movable laterally of the shoe to vary the braking effort for a given actuating force. The roller may be connected to a pivoted lever which is rotatably mounted in the back plate and which is connected to a sprung part of the vehicle by a linkage. Movement of the sprung part due to changes in vehicle loading rotates the lever and moves the roller.

Abstract: A vehicle braking system includes a pair of valve devices which compensate for variations in wheel load for each of the rear brakes. The valve devices are controlled by suspension travel through a resilient linkage assembly, but because the suspension is stiffer in roll than in bounce, the linkage is desirably more sensitive in roll. The resilient linkage includes a pair of torsion bars, each of which has a crank arm at one end and a bearing support adjacent to the crank arm. Each crank arm is connected to a respective suspension component, the torsion bars being arranged so that the reaction at the bearing support provides the main control force for the respective valve while the other end of the torsion bar is connected to the other valve to provide a compensating force which is subtractive in the bounce mode but additive in the roll mode.

Abstract: An empty and load brake device for a railroad vehicle air brake system for controlling brake application pressure comprises a housing having an inlet connected to a pressure source and an outlet connected to an air brake cylinder. A valve is positioned within the housing to control communication between said inlet and outlet. A pressure proportional piston is movable within the housing and is positioned to open and close the valve. A latch is positioned within the housing and cooperates with the piston to lock the piston in a position in which said valve is held in an open position providing full communication between said inlet and outlet. Release of the latch permits the pressure proportional piston to throttle the flow of air through said valve to provide reduced pressure at the outlet. A load sensing arm is movably attached to the housing and controls operation of the latch.

Abstract: A vehicle load-sensing assembly for use with a vehicle fluid-pressure braking system comprises an input member subjected to a force in a road spring and a valve which has a movable valve member for controlling the flow of fluid through the valve. A thrust transmitting mechanism is located between the input member and the valve member. The thrust transmitting mechanism comprises relatively movable parts, and a camming device is disposed between the parts to transmit movement between the parts to control operation of the valve member.

Abstract: A brake control apparatus for railway cars having sprung and unsprung portions is interposed between a brake pressure supply line and a brake cylinder line. A first chamber is connected to the brake pressure supply line and a second chamber is connected to the brake cylinder line. The chambers are abutted by surfaces having different cross-sectional areas of a diaphragm which is biased. A first valve responsive to positioning of the diaphragm, and a second valve responsive to positioning of a strut in a strut cylinder, effect first and second predetermined relationships between pressure drop in the brake pressure supply line and pressure drop in the brake cylinder line. The strut cylinder, mounted between the sprung and unsprung portions of the railway car, may be adapted to sense partially loaded as well as fully loaded or unloaded conditions.

Abstract: A hydraulic pressure control valve for a vehicle hydraulic braking system and of the type that is normally interposed between the brake master cylinder and the rear brakes so as to ensure that after a predetermined pressure is reached in the system a further pressure increase in the master cylinder produces a lesser increase in the rear brakes than in the front brakes. The predetermined pressure at which the valve begins to operate is controlled according to the load on the vehicle suspension, by a lever and control springs which are operated by changes in height of the vehicle chassis relative to the unsprung portion of the vehicle. The pressure control valve is made compact by having a control spring co-extensive with a part of the lever.

Abstract: A brake control apparatus for railway cars having sprung and unsprung portions is interposed between a brake pressure supply line and a brake cylinder line. A first chamber is connected to the brake pressure supply line and a second chamber is connected to the brake cylinder line. The chambers are abutted by surfaces having different cross-sectional areas of a diaphragm which is biased. A first valve responsive to positioning of the diaphragm, and a second valve responsive to positioning of a strut in a strut cylinder, effect first and second predetermined relationships between pressure drop in the brake pressure supply line and pressure drop in the brake cylinder line. The strut cylinder, mounted between the sprung and unsprung portions of the railway car, may be adapted to sense partially loaded as well as fully loaded or unloaded conditions.

Abstract: A load-responsive brake-force regulator for a vehicular hydraulic brake system includes a balance beam having a variable point of support to determine the transmission ratio for the brake pressure, two rollers disposed in a cage to support the balance beam, an actuating tongue disposed between the two rollers and two compression springs between which the cage is disposed such that the cage is centered into the position determined by the actuating tongue.

Abstract: A braking system for applying a controllable braking force to the support shaft of a film supply roll, wherein the braking force is proportional to the weight of film remaining upon the supply roll, and wherein the braking force decreases as the supply of film remaining on the supply roll decreases. The system utilizes a pair of brake yokes which are mounted on opposed sides of the frame of an unwind stand, with each brake yoke having a generally "U" configuration, and with the support shaft for the film supply roll being received within the "U" shaped member. The yokes are mounted upon rams which are controllably elevated, and when elevated, a friction pad which lines the inner periphery of the yoke makes contact with the support shaft. The rams are arranged to reciprocatorily raise and lower the yokes for bringing the friction material into and out of contact with the support shaft so as to provide controlled braking when required.

Abstract: In a system and apparatus for railway car brake control, a brake control apparatus for cars having sprung and unsprung portions is interposed between a train brake valve in a brake pressure supply line and a brake cylinder line of each railway car. A supply chamber is connected to the brake pressure supply line and a control chamber is connected to the brake cylinder line. The chambers are abutted by surfaces of a spring biased diaphragm having different cross-sectional areas. A first valve is responsive to positioning of the diaphragm, which is also selectively fluid biased by a strut cylinder mounted between the sprung and unsprung portions of the railway car, to effect predetermined relationships between pressure drop in the brake pressure supply line and pressure drop in the brake cylinder line. When the particular car is loaded, the brake cylinder line experiences a pressure drop substantially equal to that effected in the brake pressure supply line by the train brake valve.

Abstract: A brake assembly for maintaining uniform tension in plastic sheet material being unwound from a supply roll supported on a rotatable shaft. The brake assembly includes a pair of rollers which rotatably support the shaft. One roller is vertically displaceable relative to the other for controlling the movement of a linkage connected to a brake shoe in contact with the shaft. The surface area of brake lining in contact with the shaft is reduced in a proportion relative to the depletion of material from the supply roll.

Abstract: A load-sensing valve for an air pressure braking system comprises a diaphragm responsive to a signal pressure, as from a brake valve, and actuating through a rockable beam a two stage valve for controlling flow of pressure air to the brakes, the beam fulcrum being displaceable in accordance with vehicle load, and a further diaphragm having operable connection with the two-stage valve and responsive to delivery pressure, the two-stage valve consisting of a pilot valve operable alone where air usage is small to provide high sensitivity and a main inlet valve which is brought into operation with increased inlet pressure and larger air flow.

Abstract: A braking system for the front wheels of a motor vehicle. A first reducing valve is interposed between the driver's master cylinder and the brake acting on the front wheel on one side and a second reducing valve is interposed between the master cylinder and the brake acting on the front wheel on the other side. The valves are arranged so that they do not restrict braking in a straight line but a resilient linkage connected to the vehicle suspension controls braking during cornering so that the pressure to the brake on the inboard wheel is reduced. The valves give improved braking to cornering characteristics compared with previously proposed systems.

Abstract: In a method and apparatus for railway car brake control, a brake control apparatus for cars having sprung and unsprung portions is interposed between a brake valve in a brake pressure supply line and a brake cylinder line. A first chamber is connected to the brake pressure supply line and a second chamber is connected to the brake cylinder line. The chambers are abutted by surfaces having different cross-sectional areas of a diaphragm which is biased. A first valve is responsive to positioning of the diaphragm, which is fluidly biased by a strut cylinder mounted between sprung and unsprung portions of the railway car, to effect predetermined relationships between pressure drop in the brake pressure supply line and pressure drop in the brake cylinder line. The strut cylinder can be adapted to sense partially loaded as well as fully loaded or empty car conditions.

Abstract: A load-dependent four-circuit brake system is equipped with a hydropneumatic spring system, in which each spring leg includes a connection to a brake pressure regulating valve. In addition to the pressure applied by the brake pedal to the brake pressure regulating valve, also a part of the pressure prevailing in the spring leg is applied to the brake pressure regulating valve and the spring leg pressure acts, with a predetermined position of a relief valve slide member, on the brake cylinder corresponding to the respective position of the brake pedal.

Abstract: Three forms of control mechanism are disclosed for controlling the biassing load exerted on the valve members of each pressure regulator of a liquid pressure braking system which includes one such pressure regulator for controlling the brake pressure on a rear wheel on one side of the vehicle and another such pressure regulator for controlling the brake pressure on the other side of the vehicle.

Abstract: A liquid pressure braking system for a vehicle has a master cylinder which is connected to the brake operating motor cylinder on each wheel of the vehicle through a respective pressure control valve. Each pressure control valve is operated by a plunger which is linked to the suspension of the respective wheel by a respective torsion bar. Each torsion bar exerts a biassing load on the respective plunger which varies with the load supported by the respective wheel and which acts upon that plunger to open that valve. The action of the biassing load on each plunger is opposed by the loading on that plunger due to liquid pressure in the respective motor cylinder. A compression spring acts on the plunger of each pressure control valve which controls liquid pressure fed to the motor cylinders that operate the front wheel brakes so that those two valves are held open for all straight ahead braking.

Abstract: The invention relates to an automatic load-dependent brake power regulator for motor vehicles and trailers in which the regulator automatically assumes a condition to provide a braking force for a half-loaded vehicle in the event the regulator control linkage between the regulator and vehicle axle should break.

Abstract: A braking correction device comprises two correcting valves of which the inlets are separately connectible to two independent braking pressure sources and the outlets to two independent sets of vehicle brake actuators, each valve having a piston and being capable of controlling the pressures at its inlet and outlet in accordance with a predetermined relationship.

Abstract: A prior fifth-wheel braking control has a pair of links that support a trailer and rotate a small amount to operate brakes of the trailer to prevent overriding. A toggle or indexing action for stability is obtained by raising the fifth wheel and its load slightly to change positions of the links between a pulling condition and an overriding condition. The present improvement comprises adjustable stops positioned with respect to the links to determine the distance of their forward travel and therefore determine the amount of forward traction to be supplied by a tractor for changing position of the links as required for releasing the brakes of the trailer. The stops have different settings for substantially different weights of trailers to limit the amount of traction required to start the trailers.

Abstract: A skateboard having a flexible and resilient, generally planar chassis to which are affixed front and rear wheel assemblies. The skateboard includes a braking mechanism for controlling the speed of at least one of the wheel assemblies. Engagement and disengagement of the braking mechanism is controlled by and responsive to the amount and direction of the flexing of the skateboard chassis.

Abstract: A control valve assembly for a vehicle braking system comprises a control valve having a control valve operating member operable to control communication between an inlet and an outlet, a pivoted lever arrangement subjected to an input force applied by a spring and applying an output force to the valve operating member, and a device for varying the lever ratio of lever arrangement in dependence upon vehicle loading. The input force applied to the lever arrangement by the spring is substantially constant and independent of vehicle loading, variations in the lever ratio varying the load transmitted to the valve operating member.

Abstract: Empty-load fluid pressure brake equipment for a railroad car. An automatic changeover valve is operated by the pressure developed in the controlled outlet connection of a triple valve. In the empty position of the changeover valve, a volume reservoir is placed in communication with the outlet connection and the pressure developed in that connection is supplied to the brake cylinder through a proportioning valve so that a brake cylinder pressure is developed which is a predetermined fraction of the cylinder pressure developed by the same brake pipe pressure reduction in the load position. The ratio of cylinder pressure on an empty car to that on a loaded car is constant for all applications, and the volume reservoir is sized with regard to this ratio so that the equalization pressures are the same on an empty car as on a loaded car. An initial opening bias is exerted on the proportioning valve so as to prevent proportioning action during the initial stages of brake cylinder pressure development.

Abstract: A valve device for use in split liquid pressure vehicle braking systems to control rear brake pressure comprises a plunger assembly in a cavity in a housing, the cavity being closed at one end. The plunger assembly has a central land between two smaller end lands. The central land slides within a central portion of the cavity which is between two smaller portions of that cavity. The central portion and the closed end portion of the cavity are formed in a main valve body and the other cavity portion is formed in another body which is carried by the main valve body. The plunger assembly carries a bar which co-operates with the shoulder between the central portion and the closed end portion of the cavity and with a valve unseating pin to unseat a ball in a passage through the central land. A biasing spring urges the plunger assembly towards the closed end of the cavity against the action upon the plunger assembly of front brake pressure which acts between the plunger assembly and the closed end of the cavity.

Abstract: This invention relates to a transportation system comprising vehicles moved on a conveyor, guided and partly supported by wheels rolling on a guiding rail, and provided with at least one braked wheel coming into contact with braking ramps transferring the vehicles from the conveyor to stations, and with launching ramps transferring the vehicles from the station to the conveyor. A load carrying platform is connected at its corners by vertically elastic coupling members to an underframe wherein supporting and guiding members are fastened, transmitting its weight to a center of articulation where it leans on the underframe; and a braking assembly is located straight below the center of articulation in such a manner as to transmit the leaning reaction to braking members liable to come into contact with longitudinal track components.

Abstract: A brake pressure proportioner is mounted on a sprung portion of a vehicle and is attached to an unsprung portion by means of a modifying arm. The arm has ends pivoting on the unsprung portion and on a proportioner control arm so that the arm maintains a constant length during relative movements of the vehicle sprung and unsprung portions, modifying the action of the brake proportioner in accordance with such movements. The movements are proportional to vehicle load. The arm provides for compression or extension without affecting the proportioner when unsprung movements between gross vehicle curb weight (no load) and gross vehicle full weight (full load) positions are exceeded in either direction. The movement of the unsprung portion of the vehicle below the position for curb weight is known as rebound and above the curb weight position is known as jounce. The excess jounce travel beyond the gross vehicle full weight causes the arm to compress without further modifying the proportioner.

Abstract: The braking correcting device of the hydraulic type comprises a housing in which is defined a cavity. A stepped piston is disposed movable in the cavity and has one end which projects outwards from the housing, the piston having a head slidable in a bore formed in the cavity of the housing for separating the cavity into an inlet chamber which adjoins the piston end face having the smaller effective cross sectional area, and an outlet chamber which adjoins the piston end face having the larger effective cross sectional area. The piston head contains a peripheral groove which receives with axial and radial clearance a ring of elastomeric material capable of disconnecting the two chambers when the piston moves a predetermined distance from its idle position which is fixed relative to the housing, overcoming a return force. The bore comprises a first portion having a fluid tight side wall adjoining the inlet chamber, and a second portion contiguous to the first portion and adjoining the outlet chamber.

Abstract: A vehicle load responsive linking device for controlling operation of a brake pressure regulator in effecting supply of pressurized fluid to the brake system at a pressure commensurate with the prevailing vehicle load, and including a fulcrumed lever for actuating the brake pressure regulator according to a resultant force of a pair of opposing spring forces exerted thereon by respective tensionally opposingly disposed springs having adjacent ends secured to the lever and the opposite ends secured to sprung and unsprung portions, respectively, of the vehicle, the distance between the sprung and unsprung portions, as determined by the vehicle load, determining the tension of the springs, which tension acts to dampen and isolate axle vibrations from the pressure regulator device.

Abstract: Individual load-sensitive reducing valves for the rear wheels of a motor vehicle each have a spring connection to each rear wheel. The spring connection to the wheel whose braking is controlled by a particular valve provides an increase in biassing load on the valve which is at a high rate with respect to upward movement of that wheel relative to the vehicle body whereas the spring connection to the other wheel provides a decrease in biassing load which is at a low rate with respect to upward movement of that other wheel relative to the vehicle body. The arrangement compensates for differences between the bounce rates and roll rates of the rear suspension.

Abstract: An empty-load valve structure for a railroad air brake system include a load sensing valve for sensing the loaded condition of a railroad vehicle and a pressure control valve. In one position of the load sensing valve, full pressure is applied through the pressure control valve to the vehicle brakes. In a second position of the load sensing valve, less than full pressure is applied through the pressure control valve to the vehicle brakes. In all positions of the load sensing valve, a piston movable within the pressure control valve is balanced by opposing air pressure created forces.

Abstract: A change-over valve controls a source of fluid under pressure to signal at an outlet line one of two different pressures in response to applied forces such as load on a vehicle. The valve has a rotary lever load application arm receiving the applied forces to rotate it against the force of a return spring. In unloaded condition the return spring vents the outlet line to atmospheric pressure. A spring loaded valve controls the fluid pressure path to the outlet line and is operated as the applied load force increases to provide fluid under pressure to the outlet line.

Abstract: A fluid pressure operated vehicle braking system includes a control valve assembly comprising an inlet and outlet, a normally-open valve having a valve member movable in response to a predetermined inlet pressure to control the flow of pressure fluid between the inlet and the outlet, and a stepped piston subjected to a biasing force dependent upon the vehicle loading and operable in response to both the inlet pressure and the biasing force to reduce the outlet pressure after the predetermined inlet pressure is attained.

Abstract: A valve mechanism for proportioning the braking effect between the front and rear wheels of a vehicle in relation to the load carried; the valve mechanism comprising a plurality of proportioning valves which are controlled by an actuator operatively connected to the vehicle rear axle assembly, the valves being connected to the front and/or rear chambers of the master cylinder and having one of these chambers connected to the front wheel brakes.

Abstract: A braking pressure limiter device in which an inertia responsive valve normally closes under deceleration of the vehicle but has its closing action impeded by a linkage connected to an anti-roll bar so as to be responsive to the loading of the vehicle, for example the vehicle suspension to sense loading of the rear axle.