Abstract: A foldable brake pedal device for an autonomous vehicle is provided. In a manual driving mode, in which a driver directly operates a vehicle, the lower end of a brake pedal is popped up and exposed to the interior allowing the driver to manipulate the brake pedal. In an autonomous driving mode, in which the driver does not directly operate the vehicle, an actuator operates, and the brake pedal rotates causing the lower end thereof to move forward, and enter a hidden state to be prevented from being manipulated by the driver.

Abstract: A system for evacuating gas from a brake booster of a motor vehicle includes: a first conduit adapted to be connected fluidly to the brake booster; an electric pump connected fluidly to the first conduit, and controllable to evacuate gas from the brake booster via the first conduit; a second conduit; an electric valve fluidly connecting the first and second conduits to each other; a mechanical pump connected fluidly to the second conduit, and adapted to be driven by a vehicle drive unit of the motor vehicle to evacuate gas from the brake booster via the first conduit, the electric valve, and the second conduit; and a control unit operatively associated with the electric pump and the electric valve, and configured to control operations of the electric pump and the electric valve according to a working state of the mechanical pump.

Abstract: To provide a vehicle provided with a valve-stop-mechanism-equipped internal combustion engine capable of ensuring a negative pressure in a brake booster while preventing with reliability fresh air from flowing into a catalyst during a valve stop control. An internal combustion engine provided with a valve stop mechanism capable of changing the operational state of an intake valve between a valve operating state and a valve closed/stopped state is provided. A brake booster is provided capable of assisting operation of a brake pedal of the vehicle. Exhaust side negative pressure passages are provided as communication passages that are configured to be in communication with each branch pipe section of an exhaust manifold in a period in which a negative pressure is generated in the case where the intake valve is in the valve closed/stopped state while an exhaust valve is allowed to open and close. The remaining end of the second exhaust side negative pressure passage is connected to the brake booster.

Abstract: The invention relates to a braking control system for automotive vehicles comprising a braking control member (1), a brake booster (4) and a brake master cylinder (5). The system of the invention further comprises a simulator (3) coupled pneumatically to the piston (42) of the brake booster (4). Said simulator (3) receives at least one braking command from the braking control member (1) and makes it possible to establish, in return, a difference in pressure between the front chamber (40) and the rear chamber (41) of the brake booster so as to control the displacement of the piston (42). Application: Brakes for automotive vehicles.

Abstract: An apparatus and method for providing enhanced vacuum to a brake booster of a braking system under certain operational conditions. Vacuum is stored in a reservoir and is controllably released to the brake booster to provide a brake booster vacuum level of at least a predetermined vacuum level threshold in order to avoid brake pedal performance issues being perceived by the driver of motor vehicles utilizing engines utilizing a supplemental brake assist system under conditions where the brake booster vacuum level is less than the predetermined vacuum level threshold.

Abstract: A vacuum pressure booster has a booster shell; a booster piston; a valve cylinder including: a valve piston; an input rod; a control valve; and an input return spring, and the control valve including: an annular vacuum pressure introducing valve seat; an atmosphere introducing valve seat; a valve body including: an annular attaching bead portion; an expansion cylinder portion; and an annular valve portion; and a valve spring, wherein the attaching bead portion is tightly held by a pair of cylindrical holding portions formed in a pair of valve holders attached to the valve cylinder, and the diameter of the holding portion is smaller than the inner diameter of the valve cylinder.

Abstract: Master cylinder assembly (1) for hydraulic control includes a master cylinder body (2) having a longitudinal bore (3). A piston (6) is arranged in the said bore and includes a seal packing (15) separating two chambers (16, 29) adapted to contain a liquid. The piston also includes a recovery conduit (36) connecting the chambers and by-passes the seal packing, and a valve (38). When the piston is in a rest position, an actuator (54) adjusts the position of the valve between an open position opening the recovery conduit and a closed position closing the recovery conduit.

Abstract: A braking device for a motor vehicle having a first brake circuit (10) with a master cylinder (11) controlled by a brake pedal (12), a second brake circuit (20) with at least one pump (27) that is controlled by a computer (C), and a pedal travel simulation mechanism (40). The simulation mechanism (40) includes a solenoid valve (41) that is mounted in a pipe (42) connected to a hydraulic fluid storage chamber (43) and controlled by the computer (C) so as to allow the brake fluid to flow toward the chamber (43) when the second brake circuit (20) is active and when the driver presses on the brake pedal. The pipe (42) is also connected to another pipe (44) in which hydraulic fluid is displaced by a first part (45) of a control rod connected to the brake pedal (12) and second part (46) associated with the master cylinder (11).

Abstract: A brake pedal feel simulator is provided which reduces the simulation force provided to the brake pedal during emergency or failed conditions. The simulator generally comprises a first spring having a first spring rate and a second spring having a second spring rate. The second spring rate is selected to be lower than the first spring rate. When a predetermined force level is achieved at the brake pedal and simulator, the spring rate provided by the simulator shifts to the second spring rate. In this manner, the rate resistance to translation of the brake pedal is reduced, thereby improving the operator's ability to brake the vehicle.

Abstract: It is aimed to improve brake feeling of a negative pressure type brake hydraulic pressure generating device in which the stroke on the operating side can be set independently of the stroke on the output side. A spring for setting the stroke on the operating side is formed of coil springs arranged in series to impart the spring nonlinear characteristics, thereby biasing a piston, which can be moved axially relative to a power plate and includes a control valve for introducing atmospheric air, in the return direction.

Abstract: A vacuum booster apparatus used for a brake apparatus positively decreases a degree of opening of a throttle valve when it is required while an unnecessary decrease in the degree of opening of the throttle valve is positively prevented. A first pressure chamber of a vacuum booster is connected to an intake pipe of the engine on a downstream side of a throttle valve. A second pressure chamber of the vacuum booster is selectively connectable to one of the first pressure chamber and atmosphere. The vacuum booster boosts an operating force applied to a brake operating member based on a pressure difference between the first pressure chamber and the second pressure chamber. A throttle-opening-degree control device controls a negative pressure in the first pressure chamber by controlling the degree of opening of the throttle valve.

Abstract: A hydraulic brake device for a vehicle includes an auxiliary piston having an effective cross-sectional area larger than that of a master piston, and a pressure transmitting chamber provided between the large diameter portion and the master piston. The auxiliary piston is operatively associated with the assisting operation of an assisting device. A valve mechanism hydraulically closes the pressure transmitting chamber when the actuation of the master piston is assisted by the assisting device through the auxiliary piston and establishes hydraulic communication between the pressure transmitting chamber and a reservoir of the master cylinder when the master piston is not actuated by the assisting device.

Abstract: Braking device comprising a master cylinder (2), a primary piston (3), a manual control member (4), a booster (6) coupled to the manual control member (4) and an emergency assist valve (VA) comprising a reaction piston (17) through which there passes a ratio control (T) having a head (26a) situated in a chamber (35) lying between the reaction piston (17) and a bushing (36) located further forward in a bore (18) in the primary piston, this bushing (36) having a bore (37) in which there can slide a rapid piston (38), the rear end (45) of which forms, with the head (26a) of the ratio control, a valve (C) capable of closing the inlet to a passage (39) in the rapid piston against the action of a spring (41). The device comprises a means (26, 27, 30) for preventing a sharp retreat of the reaction piston (17) when the manual control member (4) is released after slow braking.

Abstract: The invention relates to a pneumatic brake-booster comprising a casing (10), inside which is situated a piston (20) consisting of a rear tubular part (22) which supports a skirt (14) and which with the aid of an unwinding diaphragm (12) defines a front chamber (16) permanently connected to a vacuum source and a rear chamber (18) selectively connected to the front chamber (16) or to the atmosphere by a valve mechanism (20a,32a, 40) actuated by a control rod (34) adapted to bear, by way of a plunger (32), against one face of a reaction disk (58) fastened to a push rod (56), the valve mechanism (20a, 32a, 40) comprising a valve closure member (40) cooperating with a first valve seat (32a) formed on the plunger (32) and with a second valve seat (20a) formed on the piston (20). According to the invention, the plunger (32) and the piston ( 20) are provided with a second valve mechanism (65, 70).

Abstract: A vacuum brake booster includes a secured arrangement for securing a flange portion of a control valve element to a cylindrical portion of the power piston so as to prevent relative movement between the flange portion of the control valve element and the power piston. Thereby, the seal surface of the control valve element is not urged toward the valve seat of the power piston by a pressure differential applied to the flange portion. The urging force of a second coil spring arrangement which urges the control valve element to separate from the valve seat in the non-operating condition of the vacuum brake booster is positively decreased without exerting an adverse influence to the control of the braking force of the vacuum brake booster (10). Accordingly, the input load of the vacuum brake booster is decreased and the operational feeling of the braking action is improved.

Abstract: A pneumatic brake booster (10) capable of operating without being actuated by a pedal (14), possesses at least one fixed part (36) and a control rod (12) with which the pedal cooperates (14). A sleeve (30) bears against the pedal (14) and partially surrounds the control rod (12), the control rod (12) possesses a shoulder (32) forming a stop cooperating with the sleeve (30) at rest and when the brake booster is actuated by the pedal (14), and the sleeve (30) is loaded by a spring (34) maintaining the pedal (14) at a given distance from the fixed part (36) of the brake booster (10) while the pedal (14) is not actuated.

Abstract: The present invention relates to a pneumatic brake booster assembly for a vehicle comprising a brake booster (10) formed from two shells (18; 37), a master-cylinder (14) mounted on the booster (10), a brake pedal (20) operatively linked to the booster (10) and mounted on a support bracket (22). According to the invention, one of the shells (18; 37) of the brake booster (10) is formed by a plate (26) upon which is mounted the support bracket (22), the plate (26) being destined to form a part of a firewall (12) of the vehicle.

Abstract: An actuating unit for anti-lock brake systems for automotive vehicles comprised of a vacuum brake power booster and a tandem master brake cylinder, wherein on failure of the primary pressure chamber a force is simulated which is opposed to the actuating force. For this purpose, a compression spring (28) is arranged in the booster housing (10) which is brought into force-transmitting engagement with the input member only after a predetermined distance of travel of the input member has occurred (3, 23).

Abstract: In the negative pressure booster equipment according to the present invention, a valve plunger 17 and an input shaft 18 are incorporated in a single member. Also, the axial length of the guide 17a of the valve plunger in relation to the valve body 4 is set to such size as to allow the angle of the maximum inclination of the input shaft 18 during operation. Further, a retainer 27 to support a spring 33 of a control valve 22 is removably mounted on the input shaft 18 from the atmospheric air inlet of the valve body 4. Accordingly, in the case of valve disc 24 is to be replaced, valve disc 24 and other rubber products can be readily replaced by removing the retainer 27 without disassembling the valve plunger 17 or the input shaft 18 from the valve body 4. Because the valve plunger 17 and the input shaft 18 are incorporated, the caulking process for the members 17 and 18 are not required.

Abstract: To substantially eliminate the noise arising upon actuation of a vacuum brake force booster caused by incoming air, the housing section confining the ventable working chamber and/or the intervals in the control valve housing are lined with an insulating composition for attenuating noise.

Abstract: An arrangement for mounting a brake power booster to a splash-board of a motor vehicle is proposed, which brake power booster is actuatable by means of an operating rod and is provided in a booster housing with at least a first evacuatable and a ventilatable second working chamber, the splash-board separating the motor vehicle's passenger compartment from a mounting compartment of the brake power booster, preferably the engine compartment.

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

Abstract: The vacuum chamber of the master booster is connected to a slave booster having a chamber also normally below atmospheric pressure. The variable pressure chamber of the master booster is connected to the other chamber of the slave booster through a check valve. The master booster operates a dual master cylinder with one pressurizing chamber connected to the rear brakes and the other pressurizing chamber connected to the master cylinder associated with the slave booster and then to the front brakes. In the first stage of actuation the master booster operates its master cylinder to pressurize the front and rear brakes equally. When a preselected boost level is reached, the pressure increase in the master booster variable pressure chamber will open the check valve and the pressure increase will be delivered to the slave booster.

Abstract: A vehicle brake having a vacuum suspended operating section. The assembly is arranged so that initial braking is accomplished by the operator admitting atmospheric pressure to the pressure side of a diaphragm that has a vacuum on its opposing side. The assembly is further arranged so that the wheel cylinder can be used to convert hydraulic pressure to air pressure. When the vehicle operator first applies a force to the brake pedal, a valve is actuated which allows vacuum and atmospheric pressure to impart sufficient force to provide initial braking. When greater brake pressures are required as indicated by increased brake pedal force exerted by the vehicle operator, a valve leading to atmospheric pressure closes, allowing the hydraulic pressure in the wheel cylinder to convert the trapped atmospheric pressure to air pressure.

Abstract: A multi-circuit brake installation for vehicles, in which two transmitter brake pistons which possess differently large effective brake pressure piston areas and which are hydraulically connected with each other, operate within a master brake cylinder actuatable at will by means of a servo-assist; these two transmitter brake pistons are connected into a respective brake circuit and are provided with corresponding means for limiting the relative movement with respect to one another, whereby control means are provided independent of the brake circuit for disengaging the hydraulic drive connection between the two transmitter pistons, which are displaced positively into the disengaging position exclusively upon the occurrence of a critical value of the servo-assist.

Abstract: A hold off valve for use in a two stage pressurizing mechanism to control the transition from a first operational condition to a second operational condition. A stepped piston in the pressurizing mechanism has a first diameter and a second diameter through which an input force sequentially operates a control valve to produce a first operational fluid force and a second operational fluid force in a pressurizing chamber. A relief chamber which is connected to the pressurizing chamber receives the first operational fluid force when the control valve is operated. The hold off valve retains the first operational fluid in the relief chamber until a predetermined pressure build up occurs after which the second diameter independently operates to produce the second operational fluid force.