摘要:
The present invention relates to a brake fluid pressure control apparatus in which a casing contains a pump communication port separately from a master cylinder communication port. A spool is also provided which limits the communication between the pump communication port and the master cylinder communication port in a manner such that the discharge pressure from the pump is not added directly to the master cylinder. Additionally, in the intake and discharge sides of the pump, a bypass channel is provided. In this bypass channel, a relief valve is provided which allows the escape of pressure force to the intake side of the pump in the case when the pressure force between the discharge side of the pump and the flow control increases to a high pressure. Furthermore, because the brake fluid is normally designed to be discharged from the pump to the flow control valve at approximately a fixed flow rate by means of the relief valve, there is no return of brake fluid to the master cylinder via the flow control valve, and stroke fluctuations of the master cylinder can be eliminated. Additionally, the necessity for providing an orifice between a pump communication port and the master cylinder communication port disappears.
摘要:
The present invention relates to a brake fluid pressure control apparatus in which a casing contains a pump communication port separately from a master cylinder communication port. A spool is also provided which limits the communication between the pump communication port and the master cylinder communication port in a manner such that the discharge pressure from the pump is not added directly to the master cylinder. Additionally, in the intake and discharge sides of the pump, a bypass channel is provided. In this bypass channel, a relief valve is provided which allows the escape of pressure force to the intake side of the pump in the case when the pressure force between the discharge side of the pump and the flow control valve increases to a high pressure. Furthermore, because the brake fluid is normally designed to be discharged from the pump to the flow control valve at approximately a fixed flow rate by means of the relief valve, there is no return of brake fluid to the master cylinder via the flow control valve, and stroke fluctuations of the master cylinder can be eliminated. Additionally, the necessity for providing an orifice between a pump communication port and the master cylinder communication port disappears.
摘要:
A dual function brake fluid control apparatus is presented for performing antiskid operation as well as another control operation involving control of the fluid pressure when the apparatus is not performing an antiskid operation. The apparatus is provided with a pressure relief valve having a valve body and a piston. The relief valve is forced closed by a biasing spring acting on a valve body, and when in the open state relieves the discharge pressure of a pump to the intake side of the pump. The piston closes the relief valve when the fluid pressure from the master cylinder exceeds a specific value. This configuration allows setting the discharge fluid pressure of the pump to apply fluid pressure to the wheel cylinders for non-antiskid control operations higher than that for the antiskid control operation. During an antiskid control operation, the fluid pressure relief valve also allows to maintain the discharge fluid pressure of the pump at the same value as or higher than the fluid pressure generated in the master cylinder.
摘要:
The present invention presents an economical fluid pressure control device particularly applicable to controlling the fluid pressure in the wheels of an automobile provided with an antiskid capability so that the unpleasant pedal kickbacks are prevented under various operating conditions of the wheels. This is achieved by providing at least two wheel cylinders for one pressure generation source, a reservoir and a pump. A flow valve provided on each of the wheel cylinders is provided with a simple flow switching device which control the position of a spool, disposed inside the flow valve, which assumes a stationary position for non-antiskid operation mode and a operation position for antiskid operation mode. When one of the wheels is in the antiskid operation mode, and the other wheel is in non-antiskid operation mode, the brake fluid discharged from the pump is not allowed to enter the flow valve disposed in the non-antiskid operation mode. Therefore, the fluid pressure pulsations generated in the fluid circuit in the antiskid operation mode are not transmitted back to the pressure generation source through the flow valve in the non-antiskid operation mode. Therefore, there in no transmission of unpleasant pedal kickbacks at the pressure generation source.
摘要:
A brake fluid pressure adjustment device is presented for controlling the wheel lock of a vehicle by controlling the flow of the brake fluid from the main fluid path to the bypass path by means of a pumping mechanism which is in constant operation. The pumping mechanism includes a suction valve which only allows a unidirectional flow of brake fluid from the pump, and a reservoir to the pump; an electromagnetic device which forces open the bypass path between the pump and the reservoir by attracting the bypass path control valve element in one direction; and a discharge valve which allows only the flow of brake fluid from the pump to the main fluid path. Therefore, by controlling the actions of the electromagnetic means, it is possible to control the decrease, holding and increase actions of the pressure adjustment device, without stopping and starting the pump. The device thereby provides a delicate and timely response to the brake pressure variation needs without being affected by the inertial effects of the pump.
摘要:
The present invention relates to a brake fluid pressure control apparatus provided with a flow valve which, during the normal operation, when a spool is in the stationary position, a master cylinder communication port is communicated with a wheel cylinder communication port while the pump communication port is closed, and during an antiskid control operation, a pump communication port and a wheel cylinder communication port are communicated, as well as a switching device to switch between the first and the second conditions. In the first condition, a master cylinder communication port is communicated with the output fluid passage of the master cylinder while the communication between the pump communication port and the master cylinder communication port is shut off. In the second condition, the communication between the master cylinder communication port and the output fluid passage of the master cylinder is shut off while the pump communication port and the master cylinder communication port are communicated. Therefore, when two functions, antiskid and traction controls, are to be provided to a brake fluid pressure control apparatus having an antiskid control capability, there is no need to change the flow valve itself, in particular the spool, to provide the two functions.
摘要:
An anti-skid device for use in a vehicle hydraulic brake system comprising a hydraulic pressure generating device for generating hydraulic pressure in response to actuation of a brake pedal, a brake cylinder for receiving the hydraulic pressure from the hydraulic pressure generating device and for applying brake force to a wheel of the vehicle, a passage through which the hydraulic pressure is adapted to be transmitted from the hydraulic pressure generating device to the brake cylinder, lock detecting device for detecting that a wheel is locked and a damping valve designed to function to interrupt the transmission of the hydraulic pressure from the hydraulic pressure generating device to the brake cylinder and to further reduce the pressure in the brake cylinder when the lock detecting mechanism detects that wheel is locked so that the wheel-lock may be released. The damping valve comprises a plunger movable such as to open and close a valve seat and a diaphragm for movably supporting the plunger and for liquid-tightly sealing a valve chamber defined around the valve seat. The plunger is integrated with the diaphragm by bonding and is provided at one end thereof with a valve body having a spherical surface portion for contacting the valve seat.
摘要:
The present invention relates to a brake fluid pressure control apparatus in which a casing contains a pump communication port separately from a master cylinder communication port. A spool is also provided which limits the communication between the pump communication port and the master cylinder communication port in a manner such that the discharge pressure from the pump is not added directly to the master cylinder. Additionally, in the intake and discharge sides of the pump, a bypass channel is provided. In this bypass channel, a relief valve is provided which allows the escape of pressure force to the intake side of the pump in the case when the pressure force between the discharge side of the pump and the flow control increases to a high pressure. Furthermore, because the brake fluid is normally designed to be discharged from the pump to the flow control valve at approximately a fixed flow rate by means of the relief valve, there is no return of brake fluid to the master cylinder via the flow control valve, and stroke fluctuations of the master cylinder can be eliminated. Additionally, the necessity for providing an orifice between a pump communication port and the master cylinder communication port disappears.
摘要:
A master cylinder of the invention supplies a brake fluid from a large diameter pressurizing chamber 56 to a small diameter hydraulic chamber 49 by opening a reverse flow checking opening and closing portion 61 by sliding movement of a stepped piston 16 forwardly, that is, fast fill and when the hydraulic pressure of the large diameter pressurizing chamber 56 rises, a control valve 86 escapes the hydraulic pressure of the large diameter pressurizing chamber 56 to a reservoir 12 to gradually lower in accordance with rise of the hydraulic pressure of the small diameter hydraulic chamber 49, thereby capable of reducing a strange feeling in a pedal feeling caused by sudden pressure release of the large diameter pressurizing chamber 56.
摘要:
A master cylinder of the invention supplies a brake fluid from a large diameter pressurizing chamber 56 to a small diameter hydraulic chamber 49 by opening a reverse flow checking opening and closing portion 61 by sliding movement of a stepped piston 16 forwardly, that is, fast fill and when the hydraulic pressure of the large diameter pressurizing chamber 56 rises, a control valve 86 escapes the hydraulic pressure of the large diameter pressurizing chamber 56 to a reservoir 12 to gradually lower in accordance with rise of the hydraulic pressure of the small diameter hydraulic chamber 49, thereby capable of reducing a strange feeling in a pedal feeling caused by sudden pressure release of the large diameter pressuring chamber 56.