Hydraulic booster with brake pressure retaining function

Abstract

Abstract PURPOSE:To make it possible to retain the brake pressure commonly to each wheel of a four-wheeled vehicle with a single solenoid valve by connecting a control pressure chamber with a hold oil chamber via a solenoid valve device opened by brake pressure retention command. CONSTITUTION:At the bottom of an inner cylinder 36a of a boost piston 33 is formed a hold oil chamber D2 faced by a stepped shoulder section of the boost piston 33. And an oil chamber D is connected via a radial flow passage 36b of a stopper ring 36, a port 42 and further a solenoid valve device 44 to a control pressure chamber C. The solenoid valve device 44 consists of a normally closed type solenoid valve 45 and a return valve 46 which allows only the flow of pressure oil of both the hold oil chamber D and the control pressure chamber C, with the both valves connected in parallel so that the pressure oil in the control pressure chamber C can be introduced into the hold oil chamber D only when the solenoid valve 45 opens its passage.

Inventors

• 👤 Naoji Iwamoto
• 👤 岩本　直司

Bibliographic Details