초록 ▼

In a brake oil pressure controlling valve device for vehicles of the type wherein a reducing valve adapted to proportionally reduce output oil pressure from a master cylinder to transmit it to a rear wheel brake and a pressure adjusting spring for urging the reducing valve in the valve opening direc

In a brake oil pressure controlling valve device for vehicles of the type wherein a reducing valve adapted to proportionally reduce output oil pressure from a master cylinder to transmit it to a rear wheel brake and a pressure adjusting spring for urging the reducing valve in the valve opening direction and determining the reduction starting pressure thereof, are interposed in an oil path connecting between an output port of the master cylinder and the rear wheel brake, the disclosed valve device is further provided with: a pressure reducing piston which is normally held by virtue of resilient force of a set spring at its advanced limit position where the reducing valve is made open and which is retreated to close the reducing valve and to reduce oil pressure on the output side of the reducing valve when the resilient force of the set spring is released; a controlling oil pressure chamber supplied with oil pressure from an oil pressure source when a rear wheel is about to come into a locked state; and a controlling piston operable with oil pressure within the controlling oil pressure chamber so as to release the resilient force of the set spring from the pressure reducing piston.

대표청구항 ▼

In an improved brake oil pressure controlling valve device for vehicles of the type wherein a valve housing is interposed in an oil path connecting an output port of a master cylinder and a rear wheel brake, said valve housing being provided therein with a reducing valve adapted to proportionally re

In an improved brake oil pressure controlling valve device for vehicles of the type wherein a valve housing is interposed in an oil path connecting an output port of a master cylinder and a rear wheel brake, said valve housing being provided therein with a reducing valve adapted to proportionally reduce output oil pressure from said output port to transmit the thus reduced oil pressure to said rear wheel brake, and with a pressure adjusting spring for urging said reducing valve in the valve opening direction and determining a reduction starting pressure thereof, the improvement wherein said valve housing is further provided therein with: a pressure reducing piston which is normally held by virtue of resilient force of a set spring at its advanced limit position where said reducing valve is made open and which is retreated, when the resilient force of said set spring is released, to close said reducing valve and reduce pressure on the output side of said reducing valve; a controlling oil pressure chamber supplied with oil pressure from on oil pressure source when a rear wheel is about to come into a locked state; a controlling piston operable with oil pressure within said controlling oil pressure chamber to allow said reducing valve to be released from the resilient force of said set spring; and wherein said output port of the master cylinder is composed of a first output port and a second output port, said rear wheel brake is composed of a right rear wheel brake and a left rear wheel brake, said oil path is composed of a first oil path connecting said first output port with said right rear wheel brake and a second oil path connecting said second output port with said left rear wheel brake, said reducing valve is composed of a pair of first and second reducing valves which are provided on the right and left side portions of said valve housing, respectively, said first reducing valve is interposed in said first oil path, said second reducing valve is interposed in said second oil path, a left front wheel brake is connected to said first oil path on the upstream side of said first reducing valve, and a right front wheel brake is connected to said second oil path on the upstream side of said second reducing valve.