Provided is a master cylinder unit including a simulator pressure chamber which communicates with a pressure chamber of a master cylinder and moves a simulator piston by means of an introduced fluid pressure; a biasing chamber in which a biasing mechanism biasing the simulator piston against a fluid pressure introduced into the simulator pressure chamber is disposed; a first seal member which partitions a simulator supply chamber, the simulator supply chamber, and the simulator pressure chamber communicating with a master supply chamber; and a second seal member which partitions the simulator supply chamber and the biasing chamber and allows a brake fluid to flow from the simulator supply chamber to the biasing chamber when a pressure difference occurs between the simulator supply chamber and the biasing chamber.

Provided is a master cylinder unit including a simulator pressure chamber which communicates with a pressure chamber of a master cylinder and moves a simulator piston by means of an introduced fluid pressure; a biasing chamber in which a biasing mechanism biasing the simulator piston against a fluid pressure introduced into the simulator pressure chamber is disposed; a first seal member which partitions a simulator supply chamber, the simulator supply chamber, and the simulator pressure chamber communicating with a master supply chamber; and a second seal member which partitions the simulator supply chamber and the biasing chamber and allows a brake fluid to flow from the simulator supply chamber to the biasing chamber when a pressure difference occurs between the simulator supply chamber and the biasing chamber.

A brake retarder valve for a tractor-trailer combination includes a valve housing and a valve assembly. The valve assembly includes a poppet valve biased by a spring and a gravity spool. The valve assembly is selectively operable between the operative closed configuration and an open configuration in response to a resultant of the fluid pressure between a trailer axle brake and a tractor axle brake. The tractor axle brake is actuated with a time delay from actuation of the trailer axle brake. This delay is actuation of the tractor axle brake prevents jack knifing of the trailer onto the tractor in a tractor-trailer combination, thereby ensuring safety during operation of a tractor-trailer combination.

A brake retarder valve for a tractor-trailer combination includes a valve housing and a valve assembly. The valve assembly includes a poppet valve biased by a spring and a gravity spool. The valve assembly is selectively operable between the operative closed configuration and an open configuration in response to a resultant of the fluid pressure between a trailer axle brake and a tractor axle brake. The tractor axle brake is actuated with a time delay from actuation of the trailer axle brake. This delay is actuation of the tractor axle brake prevents jack knifing of the trailer onto the tractor in a tractor-trailer combination, thereby ensuring safety during operation of a tractor-trailer combination.

Disclosed herein is a hydraulic unit of a brake system. According to one embodiment of the present invention, the hydraulic unit of a brake system includes a master cylinder configured to generate a hydraulic pressure to supply a braking hydraulic pressure to a wheel cylinder of a vehicle, a valve block coupled with the master cylinder to transmit the braking hydraulic pressure to the wheel cylinder and having a plurality of valves and borers, and an electronic control unit (ECU) installed at the valve block to control the plurality of valves, wherein a plurality of oil passages configured to connect the bores with hydraulic ports formed at the master cylinder are formed on a surface of the valve block to have straight lines and curved lines, and the plurality of oil passages are engraved on the surface of the valve block.

Disclosed herein is a hydraulic unit of a brake system. According to one embodiment of the present invention, the hydraulic unit of a brake system includes a master cylinder configured to generate a hydraulic pressure to supply a braking hydraulic pressure to a wheel cylinder of a vehicle, a valve block coupled with the master cylinder to transmit the braking hydraulic pressure to the wheel cylinder and having a plurality of valves and borers, and an electronic control unit (ECU) installed at the valve block to control the plurality of valves, wherein a plurality of oil passages configured to connect the bores with hydraulic ports formed at the master cylinder are formed on a surface of the valve block to have straight lines and curved lines, and the plurality of oil passages are engraved on the surface of the valve block.

A rotating pumping apparatus is provided which may be employed in an automotive brake system. The rotating pumping apparatus includes a sealing member and a pressure member. The sealing member is disposed around a pump drive shaft. The pressure member includes a plate spring, a first rotation stopper, and a second rotation stopper. The first rotation stopper serves to stop the pressure member from rotating following rotation of the pump drive shaft. The second rotation stopper engages the seal ring to stop the sealing member from rotating following the rotation of the pump drive shaft. The plate spring works to elastically press the sealing member against a stopper wall of a pump casing to stop the sealing member from moving in an axial direction of the pump drive shaft.

A rotating pumping apparatus is provided which may be employed in an automotive brake system. The rotating pumping apparatus includes a sealing member and a pressure member. The sealing member is disposed around a pump drive shaft. The pressure member includes a plate spring, a first rotation stopper, and a second rotation stopper. The first rotation stopper serves to stop the pressure member from rotating following rotation of the pump drive shaft. The second rotation stopper engages the seal ring to stop the sealing member from rotating following the rotation of the pump drive shaft. The plate spring works to elastically press the sealing member against a stopper wall of a pump casing to stop the sealing member from moving in an axial direction of the pump drive shaft.

A brake control device includes: a liquid pressure line provided for each vehicle wheel and supplied with a brake liquid pressure; a pressurization unit configured to supply a pressurization brake liquid pressure to the liquid pressure line; an abnormality detection unit configured to detect an abnormality of the liquid pressure line at a time the brake liquid pressure of the liquid pressure line is not greater than a threshold value; and a pressurization adjustment unit configured to continuously supply the pressurization brake liquid pressure to the liquid pressure line of the normal vehicle wheel having a low abnormality occurrence risk and suppress the supply pressure of the pressurization brake liquid pressure to the liquid pressure line of the vehicle wheel having a high abnormality occurrence risk until the abnormality of the liquid pressure line is detected by the abnormality detection unit.

A brake control device includes: a liquid pressure line provided for each vehicle wheel and supplied with a brake liquid pressure; a pressurization unit configured to supply a pressurization brake liquid pressure to the liquid pressure line; an abnormality detection unit configured to detect an abnormality of the liquid pressure line at a time the brake liquid pressure of the liquid pressure line is not greater than a threshold value; and a pressurization adjustment unit configured to continuously supply the pressurization brake liquid pressure to the liquid pressure line of the normal vehicle wheel having a low abnormality occurrence risk and suppress the supply pressure of the pressurization brake liquid pressure to the liquid pressure line of the vehicle wheel having a high abnormality occurrence risk until the abnormality of the liquid pressure line is detected by the abnormality detection unit.