摘要:
A solenoid valve includes a valve housing having first, second, and third valve ports, an actuation rod, a first tip valve actuated by the first end of the actuation rod to allow or block fluid passage through the first valve port, and a second tip valve actuated by the second end of the actuation rod to allow or block passage through the second valve port. A vacuum booster diaphragm subassembly includes a vacuum booster diaphragm and a grommet attached to the vacuum booster diaphragm. A vacuum booster assembly includes the above-described solenoid valve, includes primary and secondary diaphragms, and includes the above-described grommet attached to the secondary diaphragm, wherein the secondary diaphragm is the above-described vacuum booster diaphragm.
摘要:
A hybrid brake apparatus for a vehicle includes a hydraulic brake circuit having a first fluid circuit and a second fluid circuit connected to a master cylinder for generating hydraulic pressure in the first and a second fluid circuits, and electrically actuated brake elements controllable as a function of the hydraulic pressure in one or the other of the first and second fluid circuits. The apparatus may include a pedal feel emulator in one of the fluid circuits. The apparatus may also include a booster for amplifying pressure in the fluid circuits, a sensor for determining that the booster has failed, and control elements providing compensation for the failed booster during operation of the electrically actuated brakes while the booster is inoperative.
摘要:
A brake booster provides additional boost capacity without unduly increasing booster size and weight by providing a vacuum pump connected so as to add its additional vacuum capacity to that of the normal vacuum source when activated in response to sensed approaching run-out. The additional vacuum is provided by connecting the vacuum pump in a second conduit between the vacuum source and the booster vacuum chamber in parallel with a first conduit connecting the vacuum source directly with the booster vacuum chamber, with check valve means in the first and second conduits preventing substantial vacuum loss from the vacuum chamber. Approaching run-out is signaled by a sensor responsive to a vacuum level in the working chamber; and control means are responsive to a predetermined low value of the sensed vacuum level in the working chamber to activate the vacuum pump and thus increase the vacuum level in the vacuum chamber over that produced by the vacuum source, whereby a greater pressure differential is available across the booster diaphragm before run-out is encountered. An optional sensor responsive to vacuum level in the vacuum chamber enables the vacuum pump to be additionally used for backup of the vacuum source while still providing the functionality of the invention in most cases. The venting of the vacuum pump to the vacuum source reduces released noise which might otherwise require bulky noise filter apparatus.
摘要:
A self contained, supplemental vacuum assist unit is provided for use with a vacuum brake booster and a source of vacuum in a motor vehicle. The unit includes, within a single housing, an electric motor, an air pump driven by the motor, a manifold defining air exhaust and assist vacuum chambers, a pair of check valves permitting air flow from the pump outlet and the assist vacuum chamber to the air exhaust chamber, an outlet from the air exhaust chamber with a fitting for connection to the vacuum source, an opening from the assist vacuum chamber with a fitting providing communication directly to the interior of the vacuum chamber of the booster, and a pressure sensor including a diaphragm, plunger, magnet with a Hall effect sensor and motor control circuitry on a circuit board within the assist vacuum chamber. The unit is compact, light weight and efficient and is designed for attachment directly to the booster with no intervening vacuum hose therebetween.