摘要:
An anti-lock hydraulic brake system comprising a separating valve (14) and a regulating valve (19). A combined arrangement is provided wherein the valves are connected into each other. The movability (play s) of the piston (30) affords the event that a compensating volume for the control action in the event that the output of the pump is insufficient in specific situations requiring a large amount of fluid for control.
摘要:
An anti-lock hydraulic brake system is described wherein a throttle valve has a restrictive flow condition which becomes effective in the brake line in the event of brake slip control. Pumps for reapply pressure deliver fluid to the wheel brake via this restriction and regulating the pressure in the wheel brake is performed by control of an outlet valve. The throttle valve is operated hydraulically by various arrangements including the application of pump pressure, or by wheel brake pressure applied upon opening of the outlet valve at the start of an anti-lock control cycle.
摘要:
A brake system which can be employed both for brake slip control and for traction slip control, wherein the brake slip control is performed according to the return delivery principle, while an open-loop system is set up during traction slip control. In order to manage with the same pump (10) in both cases, a valve system composed of a first non-return valve (16) and a second non-return valve (17) is provided at the suction side of the pump. The opening pressure of the first non-return valve (16) is greater than that of the second non-return valve (17). Further, the initial pressure of a low-pressure accumulator (9) is in excess of the opening pressure of the first non-return valve (16). The first non-return valve (16) is operative during brake slip control, while the second non-return valve (17) is operative during traction slip control. Switch-over can be effected for instance by the master cylinder pressure via a control line (18).
摘要:
A hydraulic anti-locking brake unit is presented in which the brake line is shut off by an isolating valve (20) during a control action. For the reduction of the pressure, the outlet valve (7) is opened, so that the pump (14) delivers hydraulic fluid out of the wheel brake into the high-pressure accumulator (19). For a renewed pressure build up, the inlet valve (6) is opened, so that hydraulic fluid flow is directed out of the high-pressure accumulator (19) back to the wheel brake. In order to be able to utilize a high-pressure accumulator having a low receiving capacity, various valving arrangements are disclosed to direct excess flow from the pump either to the master cylinder or a low pressure accumulator.
摘要:
A hydraulic anti-locking brake unit is presented in which the brake line is shut off by an isolating valve 20 during a control action. For the reduction of the pressure, the outlet valve 7 is opened, so that the pump 14 delivers hydraulic fluid out of the wheel brake into the high-pressure accumulator 19. For a renewed pressure build-up, the inlet valve 6 is opened, so that hydraulic fluid flow is directed out of the high pressure accumulator 19 to the wheel brake. In order to be able to utilize a high pressure accumulator having a low receiving capacity, various valving arrangements are disclosed to direct excess flow from the pump either to the master cylinder or a low pressure accumulator.
摘要:
In an anti-lock brake control system having a vacuum brake power booster and a tandem master cylinder, in which the brake pedal is controlled to be positioned forwardly of the initial return position during the anti-lock control mode. This is achieved by variation of the rate of delivery of an auxiliary pump as by switching the pump motor on and off by a switch actuated by the diaphragm of the power booster to provide a signal of the pedal position at the start of an anti-lock control phase. Various switching arrangements described include a Bowden-cable pulled by the diaphragm, a mechanical or an optical switch actuated by the rolling lip of the diaphragm, or an approach switch detecting the approach of the diaphragm and cam-assembly. The core (53) of the Bowden cable (54) is connected with the diaphragm plate (52) of the vacuum brake power booster. The core (53) moves the trigger cam (64). The switch (18) is actuated by the movement of the trigger cam (64).
摘要:
A brake pressure control apparatus for automotive vehicles with an anti-locking control system (ABS) and/or with a traction slip control system (TSS) is presented. In the inlet line to the wheel cylinder an inlet valve is provided which affords a change-over from an orifice function into a flow limiting valve function at a predetermined wheel cylinder pressure. Flow is initially through an orifice (6) in a control slide valve piston (20), held in its initial position by a prestressing spring (23) acting through an auxiliary piston in engagement with control slide valve piston (20). An increase in pressure in the wheel cylinder (13), also exerted in the wheel cylinder pressure chamber (9), to a predetermined level, causes the auxiliary piston (27) to disengage from the control slide valve piston (20), preventing the force of the prestressing spring (23) from acting on the control slide valve piston (20). As a result, the control slide valve piston (20) is free to reach an equilibrium position corresponding to the magnitude of the remaining forces acting upon the piston (20 ). A control edge (33) on the piston (20) establishes a flow cross-sectional area (34) which, upon the filling of the wheel cylinder (13), leads to a constant nominal flow rate within the lines (19, 11, 12) to the wheel cylinder (13). The invention is distinguished in that precisely defined pressure gradients, a better adaptation to the volume accommodating curve of the wheel circuit and a better exploitation of the pump characteristic are achieved.
摘要:
A brake pressure control for use with an automotive anti-locking control system (ABS) and/or a traction slip control system (ARS) is provided. The control comprises a pressure modulator for varying the hydraulic pressure in the wheel cylinder (13) during the brake pressure control mode, with the pressure modulator exhibiting at least one inlet valve and at least one outlet valve (21) associated with the wheel cylinder (13), at least one motor-driven pump (6) for generating a hydraulic pressure, and an electronic controller. The inlet valve is pressure actuated and comprises a piston-cylinder assembly including a piston (7) forcing, upon application of the brake pressure, a filling volume (14) into the wheel cylinder (13), followed by a throttled rise in pressure caused by a throttling flow restriction (16) defined through the piston.
摘要:
A brake pressure control apparatus having a brake pressure master unit, a brake connected to the brake pressure master unit through a pressure line, a pressure-controlled inlet valve which is positioned in the pressure line and through which the brake pressure master unit is connected, in a first switching position, through a restrictor orifice to the brake and which is furnished with a control piston which in one direction is subject to the pressure in the pressure line and in the opposite direction is subject to the action of a spring and of the pressure in a return line which contains an outlet valve which is controllable by a control device, which blocks the return line in its position of rest and which releases the return line in its switching position. The inlet valve is provided with a valve element which interacts with the control piston and which, in the second switching position, blocks the pressure line and releases a valve seat formed by a longitudinal bore of the control piston making the brake pressure slave unit connectible to the return line.
摘要:
A brake pressure control apparatus for automotive vehicles with an anti-locking control system (ABS) and/or with a traction slip control system (TSS) is presented. In the inlet line to the wheel cylinder an inlet valve is provided which affords a change-over from an orifice function into a flow limiting valve function at a predetermined wheel cylinder pressure. Flow is initially through an orifice (6) in a control slide valve piston (20), held in its initial position by a prestressing spring (23) acting through an auxiliary piston in engagement with control slide valve piston (20). An increase in pressure in the wheel cylinder (13), also exerted in the wheel cylinder pressure chamber (9), to a predetermined level, causes the auxiliary piston (27) to disengage from the control slide valve piston (20), preventing the force of the prestressing spring (23) from acting on the control slide valve piston (20). As a result, the control slide valve piston (20) is free to reach an equilibrium position corresponding to the magnitude of the remaining forces acting upon the piston (20 ). A control edge (33) on the piston (20) establishes a flow-cross-sectional area (34) which, upon the filling of the wheel cylinder (13), leads to a constant nominal flow rate within the lines (19, 11, 12) to the wheel cylinder (13).