A hydraulic dual circuit vehicle brake system includes a slip control member and a piston/cylinder unit between pressure sides of two piston pumps for a more homogeneous brake fluid delivery. The piston of the piston/cylinder unit is clamped in elastically between two elastic and annular displacement bodies.

A guide ring for a piston pump of a vehicle brake system includes a body and a seal. The body is configured to movably support a piston of the piston pump in a cylinder liner. The seal is held on the guide ring and configured to inhibit passage of air between the piston and the guide ring during movement of the piston.

Disclosed is a hydraulic control apparatus of a brake system including a modulator block having a motor bore, and a motor including a cover that covers an opening of a case accommodating a stator and a rotor and is supported on one side of the modulator block, wherein a vent hole for air flow between the inside and the outside of the motor is formed on the cover and a communication passage for communicating the motor bore and the vent hole is formed in the modulator block.

A device for choking a fluid flow includes a pot-like base body, in the base of which a first passage opening is arranged, and a closing body guided axially moveably in the pot-like base body against a spring force of a spring element and having a second passage opening that forms a static choke point with a predefined fixed opening cross section. The closing body in combination with the spring element and the first passage opening forms a dynamic choke point with a dynamic opening cross section that is variably adjustable depending on a pressure difference.

Provided is a plunger pump where quietness can be ensured. A plunger pump includes a cylinder, a piston, a discharge valve, and a plug member. The plug member includes: a recessed portion formed on a circumferential wall of a discharge chamber opposing an outer periphery of the discharge valve in a radial direction; and a discharge passage disposed at a position different from the recessed portion, formed on the circumferential wall of the discharge chamber opposing the outer periphery of the discharge valve in the radial direction, and connecting the discharge chamber and the outside with each other.

A plunger pump having improved durability without leading to a reduction in productivity is provided. A pump apparatus includes a sliding portion provided between a stopper portion and an eccentric cam in a direction of an eccentric central axis and having a lower frictional coefficient between the sliding portion and the eccentric cam than a frictional coefficient between the stopper portion and the eccentric cam.

Example hydraulic brake actuators and related methods are disclosed herein. An example hydraulic brake actuator includes a rotary valve disposed in a bore of a housing. The rotary valve includes a shaft rotatably disposed within a sleeve. The sleeve and the shaft have ports that align at certain rotational positions to create a flow path between the bore and an inner chamber of the shaft. The example hydraulic brake actuator also includes a pump coupled to the shaft to increase and decrease a pressure within the inner chamber of the shaft.

A plunger pump is provided which comprises: a pump body having a cylinder hole with an expanded diameter section; a plunger defining, together with the lid member, a pump chamber; and a coiled spring disposed within the expanded diameter section. The coiled spring includes: an effective winding section; a lid-side seat winding section; and a plunger-side seat winding section. The lid-side seat winding section has an outer diameter larger than an outer diameter of the effective winding section, and the plunger-side seat winding section has an outer diameter smaller than an outer diameter of the plunger. With this configuration, the coiled spring within the pump chamber can have increased stability, and can be located in the center of the pump chamber.

A fluid filter for a fluid device with one or more of a pump element and a solenoid valve in a motor vehicle, in particular for an ESP system. The fluid filter is formed by direct injection molding and has at least one filter connecting piece. The filter connecting piece has an outer section, a middle section, and an inner section. The outer section is in the form of a projection that is directed outwards with respect to the fluid filter. The inner section is in the form of a projection that is directed inwards with respect to the fluid filter.

A brake system for a vehicle, may include a brake input device to apply a brake input of a driver; a brake actuator generating braking hydraulic pressure; wheel cylinders generating braking force for each vehicle wheel by the braking hydraulic pressure generated by the brake actuator; and a hydraulic pressure supply line connecting the brake actuator and the wheel cylinders, wherein the brake actuator includes a main pump device by which braking force is applied, and a sub control device configured for adjusting the braking force applied by the main pump device.