Brake master cylinder device

Abstract

Abstract PURPOSE: To dispense with large tread force by providing a unidirectional valve and an accumulator and also a valve which opens the outlet passage of a resevoir only when the piston is located in the returned position in the cylinder on one side of pistons in a cylinder equipped with large and small bores. CONSTITUTION: The first and second pistons 7, 9 equipped with lands 5, 6, 9' respectively engaged with its large and small diametral bores 3, 4 are housed in a cylinder member 1. The piston 7 provides a ring-shaped seal member 31 which functions as a unidirectional valve to allow only passage of fluid pressure from a chamber 10 to a chamber 11, moves to the right against a spring 38 when the fluid pressure in the chamber 10 becomes more than a settled value, and provides an accumlator piston 34 to accumulate fluid pressure in an accumulator chamber 35. Besides, a valve 25 to open a passage 23 is installed in the cylinder member 1 so that only when the piston 7 is located at the returned position, it is actuated through a rod 26 by the land 6. COPYRIGHT: (C)1981,JPO&Japio

Inventors

• 👤 Yutaka Kawaguchi

Bibliographic Details