摘要:
In an anti-lock brake system, a differential pressure limiter (8) is connected in front of the inlet valve (6). This causes a defined pressure gradient to always prevail at the inlet valve (6), what appreciably reduces the noise emission of the valve during an anti-lock braking operation. Since the inlet valve (6) has a slight throttling effect in its opened position, it may occur that on brake operation with cold brake fluid a pressure gradient is generated at the inlet valve (6) which results in the differential pressure limiter closing. It is therefore suggested to arrange a bimetal spring (20) in parallel to the control spring (15) of the differential pressure limiter (8), which bimetal spring expands at low temperatures and cases a force in addition to the spring force of the control spring (15) to act on the control piston.
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:
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 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 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 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).
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:
The brake system includes a brake pressure generator with a master cylinder connected to wheel brake cylinders through master brake conduits; auxiliary pressure pumps having pump outlets in communication with the master brake conduits and pump inputs in communication with a pressure fluid reservoir through inlet conduits; wheel sensors and electronic circuits for determining the wheel rotating pattern and for generating electrical brake pressure control signals capable of controlling pressure fluid inlet and outlet valves disposed in the conduit system for slip control. The traction slip control system insures, with little effort involved, assembling and disassembling capabilities, and, in disassembled condition, complying with the control principle for a driven front axle and, in assembled condition, complying with the traction slip control mode for a driven rear axle in all speed ranges. The present invention provides an accumulator with a single connection in communication, with the master brake conduit, with an electromagnetic valve having a pressure monitoring switch coupled thereto and provided with a bypass enclosing a release valve located between the connection and the accumulator.
摘要:
The invention pertains to an electrohydraulic pressure control device, with electromagnetically actuated hydraulic valves, which are arranged on a valve-holding element, with coils which extend beyond the valve-holding element, whereby the coils are provided with electrical contact elements at their parts extending beyond the valve-holding element, with a cover which covers the extending coil parts and the contact element, with a support element to hold the coils, that are positioned within the cover, whereby the cover or a portion of the cover is designed as an electromagnetic controller or for holding the connecting parts of an electronic controller. An essentially plate-like carrier element facing the coils features several slots into which form- and/or pressure-locking closing devices are engaged projecting from the outer surface of the cover.