Vehicular hydraulic-pressure-generation device and vehicular braking-force generation device

摘要

A vehicular hydraulic-pressure-generation device wherein a first bush compressively deforms due to pressure from a simulator piston that moves when hydraulic pressure produced when a brake pedal is depressed is transmitted into a cylinder part. Said vehicular hydraulic-pressure-generation device thus creates artificial reaction-force characteristics with respect to the position of the brake pedal. The aforementioned first bush has a third elastic modulus, which is smaller than a second elastic modulus, and is provided in parallel with a first return spring. The compressive deformation of the first bush occurs over a second region that overlaps a first region in which compressive deformation of the return spring primarily occurs. This makes the brake pedal move more smoothly, reducing the feeling of incongruity resulting from a V-shaped singularity in the reaction-force characteristics with respect to brake pedal position.

主权项

1. A vehicular braking-force generation device, comprising:
a hydraulic pressure generation section for generating a hydraulic pressure corresponding to an operation amount of a brake operation member by a driver; and a reaction force generation section communicated with the hydraulic pressure generation section to generate, against the driver, a reaction force corresponding to the operation amount of the brake operation member, wherein the reaction force generation section includes a simulator piston that is operated to move in a forward direction or in a backward direction, corresponding to the hydraulic pressure generated by the hydraulic pressure generation section, the simulator piston being housed in a simulator housing, wherein the hydraulic pressure generation section includes: a first piston and a second piston provided to be forward and backward movable in a master cylinder, in association with the brake operation member; a first hydraulic chamber partitioned by an inner wall portion of the master cylinder, the first piston, and the second piston; and a second hydraulic chamber partitioned by the inner wall portion of the master cylinder and the second piston, the second hydraulic chamber being communicated with the reaction force generation section, wherein a maximum value of hydraulic pressure generated in the second hydraulic chamber is set smaller than a maximum value of hydraulic pressure generated in the first hydraulic chamber, and wherein, when the second piston reaches a bottom of the master cylinder by an operation of the driver, the simulator piston does not yet reach a bottom of the simulator housing.