Abstract:
A brake fluid pressure retaining unit for a vehicle comprises a solenoid valve SV arranged in a brake fluid passage FP between a master cylinder MC and a wheel cylinder WC so as to shut off or communicate the brake fluid passage FP. In the case that a transmission of the vehicle is shifted to a driving position, the solenoid valve SV is switched to a shut-off position when the vehicle stops with a brake pedal BP depressed. The solenoid valve SV is switched to a communicating position when driving force is exerted on the vehicle. Brake fluid pressure is retained within the wheel cylinder WC when the solenoid valve SV is in the shut-off position. The brake fluid pressure within the wheel cylinder is retained after releasing the brake pedal so that braking force continues to act on the vehicle. The brake fluid pressure retaining unit comprises control means CU such that when the solenoid valve is in the shut-off position and the transmission is shifted to a non-driving position, the solenoid valve SV is returned to the communicating position on condition that depression of the brake pedal BP is released.
Abstract:
A motorcycle rear wheel brake functions to allow the driver to lock the rear wheel on an upward incline. This prevents the motorcycle from rolling backwards while freeing the driver's hands and feet. A simple hinge arrangement wedges the rear wheel and the hinge into the rear fork. A solenoid activates the hinge. An alternate embodiment uses a mechanical cable to move the hinge.
Abstract:
The invention covers a brake-booster of the partial vacuum type comprising a direct braking control mechanism (hill-holder or traction control). In order to implement these functions, the piston (20, 22) of the booster is "double" through a partition (52) which is attached securely to the piston and defines with the piston a third chamber (50). This chamber is connected by a flexible pipe (66) and a double valve (72) either to partial vacuum (78) or to atmospheric pressure (76).
Abstract:
An hydraulic braking system includes a primary pressure source connected to a brake actuator and operable by a force input device, a fluid displacer actuated by an electrical stepper motor operated by a controller in response to action of the force input device, as sensed by a sensor, whereby fluid displaced from the displacer is added to that displaced from the primary pressure source for application to the brake actuator. By suitable programming of the controller, servo-assistance and/or quick-fill modes can be produced by the displacer and wheel-slip correction and anti-skid facility can be provided.
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:
A wheel chair (A) has at least one wheel (50) rotatably mounted to a side frame (14). A combined wheel lock and hill holder assembly (D) is mounted adjacent an outermost peripheral surface of a tire (60) mounted to a rim (58) of the wheel. The wheel lock and hill holder assembly has a linkage including a handle member (74) and a brake lever (80) both pivotally connected to the base. A link (84) is pivotally connected in between. Shifting the handle member causes the brake lever to move an axle (90) toward and away from the peripheral surface of the tire. A cam surface (94) having a plurality of projections (102) is rotatably mounted on the axle. In a first mode (FIG. 3), the wheel is free rolling. In a second mode (FIG. 4), the cam surface is moved by the handle into firm friction engagement with the tire peripheral surface to lock the wheel against any rotation. In a third mode (FIG. 5), the cam surface is spring biased into engagement with the wheel such that rotation in one direction is permitted but rotation in the opposite direction causes increasing engagement between the cam and the tire peripheral surface locking the wheel against rotation in that direction.
Abstract:
A brake booster (10, 210, 310) connected to a control circuit (120) provides a system for the continued braking of a vehicle when the vehicle is situated on an incline and the brake pedal (92) is released by the operator. Continued brake application is accomplished by utilizing a control circuit (120) responsive to vehicular attitude, clutch pedal position, ignition status, vehicular speed, and vehicular direction. The control circuit (120) is connected to the combination of a check valve and three-way solenoid valve (100, 200, 300) connected to a movable wall brake booster (10, 210, 310). The combination valve (100) is connected to a flexible hose (110) disposed interiorily of the booster (10), the other end of the flexible hose (110) connected to the input opening (32) of a three-way poppet valve (70) located at the central hub (30) of the booster (10). When the control circuit (120) senses that the vehicle is on an incline, the clutch pedal depressed, the ignition "on", the speed is zero, and the vehicle not backing up, it actuates the three-way solenoid of valve (100) which continues to supply a first fluid pressure to the front booster chamber (40) while supplying a second fluid pressure for the rear booster chamber (50) via the flexible hose (110) and poppet valve (70). The vehicle operator may release the brake pedal (92) which returns slightly toward an inactive position and which opens slightly valve (70), with the brakes remaining activated because the second fluid pressure is provided to the rear chamber (50) via the hose connection (110) and valve (70) to maintain the axially displaced position of the movable wall (24).
Abstract:
The improved release mechanism comprises a load sensor (50, 51, 150, 250, 350, 450) connected with a wheel brake (10, 110) to sense a change in wheel braking torque and communicate responsively with a mechanical brake control device (200) or a braking assistance servo-motor system (310, 320; 410, 420) which releases the brakes when the vehicle commences acceleration along an incline.
Abstract:
A brake pedal contacts a pin holding the push rod for the master cylinder, applying the hydraulic service brakes in the normal manner when the pedal is depressed. When the transmission lever is shifted into the park position a solenoid type servo is energized, engaging a pawl, mounted on the brake pedal, with a gear sector pivoted about the pivot point of the brake pedal. A one-way spring clutch is energized to hold the link in which the push rod pin is installed in the applied position during parking brake apply, retaining hydraulic brake pressure during that operation. When shifting to park, the brake pedal is raised by a vacuum servo so that the pedal can be actuated to apply the parking brake without contacting the push rod pin, and therefore without hydraulic pressure resistance. Movement of the pedal with the pawl engaged exerts tension on the parking brake cable through the gear sector to apply to parking the brake. When the ignition key is turned off, the spring clutch is released and the hydraulic service brakes are released. The pawl is retracted when the ignition key is turned off, and another spring clutch prevents release of the parking brake. This clutch is released upon shifting the transmission lever from park. A circuit is provided which prevents reengagement of the pawl until the transmission lever is shifted out of and then back into park.
Abstract:
A tow vehicle adapted to be guided for movement along a slot is provided with swivel castor wheels at the front end of the vehicle. The front castor wheels are provided with roller clutch bearings which act as a brake to prevent the vehicle from being moved in a rearward direction.