A vehicle brake hydraulic pressure control apparatus installed in a vehicle changing a drive torque transferred to a wheel during a halt, includes vehicle holding section for performing vehicle holding control that holds an actual brake hydraulic pressure applied to the wheel during a halt and storage section for storing a holdable hydraulic pressure capable of holding the halt state of the vehicle before and after the drive torque changes during a halt, in which when determining that the actual brake hydraulic pressure is less than the holdable hydraulic pressure (first hydraulic pressure P1) at a start (time t1) of the vehicle holding control, the vehicle holding section increases the actual brake hydraulic pressure to the holdable hydraulic pressure and holds the holdable hydraulic pressure.

A brake control system of a vehicle, including a first electric motor, a second electric motor, a first piston cylinder and a second piston cylinder. Each piston cylinder includes a hydraulic chamber and a piston, where the position of the piston defines the volume of the hydraulic chamber. The system includes a plurality of wheel cylinders and a hydraulic control unit which includes two sets of electromagnetic valves. Each of electric motors are mechanically connected to the piston of respective piston cylinder via a motion converter that converts rotational motion of the electric motor to linear motion of the piston, thus changing the pressure of the hydraulic chamber. The hydraulic chambers are hydraulically connected with the respective set of the electromagnetic valves, further connecting to corresponding wheel cylinders.

A hydraulic pressure control unit capable of suppressing application of an external force thereto in comparison with the related art at the time when mounted to a straddle-type vehicle is obtained. A hydraulic pressure control unit (1) includes a base body (10) that is formed with a master cylinder port (11), a wheel cylinder port (12), and an internal channel (13) communicating the master cylinder port (11) and the wheel cylinder port (12) with each other. The master cylinder port (11) is formed in an upper surface (25) of the base body (10), and the wheel cylinder port (12) is formed in a lower surface (26) of the base body (10), the lower surface (26) opposing the upper surface (25). The internal channel (13) is configured not to be able to return a brake fluid in an accumulator (33) to the master cylinder port (11) without interposing an outlet valve (32). An inlet valve recess (18) and an outlet valve recess (19) are aligned in a direction in which the upper surface (25) and the lower surface (26) are aligned.

A cuboidal housing block, particularly for a hydraulic modulator to generate, control or regulate a hydraulic pressure in a brake circuit of an electronically controllable power-brake system. Housing blocks have, inter alia, a mounting side which is provided for mounting an electronic control unit. To save on weight and material, a recess is provided on one long side of the housing block, the recess being in the form of a groove that is closed on the sides and otherwise open toward the surroundings of the housing block. The recess is bounded lengthwise by bars, an outer flank of these bars transitioning seamlessly into the mounting side and enlarging its area.

A vehicle braking device includes: a first hydraulic pressure output unit that is connected to a master chamber through a first liquid passage and outputs hydraulic pressure to first wheel cylinders based on a hydraulic pressure of the first liquid passage; a hydraulic pressure generating unit that generates hydraulic pressure independently of a master cylinder; a second hydraulic pressure output unit that is connected to the hydraulic pressure generating unit through a second liquid passage and outputs hydraulic pressure to second wheel cylinders based on a hydraulic pressure of the second liquid passage; a normally closed communication control valve that is provided in a communication passage connecting the first liquid passage and the second liquid passage and opens and closes the communication passage; and a normally open master cut valve in the first liquid passage on the master cylinder side relative to a connection portion with the communication passage.

A vehicle braking device includes: a first hydraulic pressure output unit that is connected to a master chamber through a first liquid passage and outputs hydraulic pressure to first wheel cylinders based on a hydraulic pressure of the first liquid passage; a hydraulic pressure generating unit that generates hydraulic pressure independently of a master cylinder; a second hydraulic pressure output unit that is connected to the hydraulic pressure generating unit through a second liquid passage and outputs hydraulic pressure to second wheel cylinders based on a hydraulic pressure of the second liquid passage; a normally closed communication control valve that is provided in a communication passage connecting the first liquid passage and the second liquid passage and opens and closes the communication passage; and a normally open master cut valve in the first liquid passage on the master cylinder side relative to a connection portion with the communication passage.

A valve unit for an anti-lock braking system has a valve body, a piston, and an elastic element acting on the piston. The valve body has an outlet port, an inlet port, a primary chamber communicating with the outlet port, an expansion chamber with an outflow passage establishing fluid communication between the primary chamber and the expansion chamber, and a bypass passage between the inlet port and the outlet port. The piston is movable in the primary chamber and has a longitudinal through cavity, a first transversal surface facing the outlet port, and a second transversal surface facing away from the outlet port. The first transversal surface has an area smaller than the area of the second transversal surface. The elastic element exerts an elastic force to move the piston away from the outlet port. The valve unit is activatable by pressure of a brake fluid in the primary chamber.