Hydraulic braking device

Patent metadata

Field	Value
Publication number	US-2017203740-A1
Application number	US-201515326153-A
Country	US
Kind code	A1
Filing date	Jul 14, 2015
Priority date	Jul 15, 2014
Publication date	Jul 20, 2017
Grant date	—

Abstract

This hydraulic braking device is provided with: a tubular cylinder; an assisting piston, which is housed in the cylinder so as to be able to move reciprocally, faces a reservoir formed inside the cylinder, and assists a master piston, in a master cylinder, that generates hydraulic pressure for generating a braking force by reciprocally moving from one side to the other as a result of a fluid flowing into the reservoir from a supply source; and a seal member, which is elastically deformable and which seals the reservoir. When the assisting piston is at a location on one side, the reservoir is compartmentalized into a first chamber that communicates with the supply source, and a second chamber that communicates with the first chamber through a restricting flow passage, and the seal member seals the second chamber.

First claim

1 . A hydraulic braking device comprising:
a tubular cylinder; an assisting piston housed in the cylinder so as to be movable reciprocally, the assisting piston facing a fluid chamber formed in the cylinder, the assisting piston assisting a master piston of a master cylinder generating a hydraulic pressure for generating a braking force when moved from a location on one side to another side in a reciprocal movement direction by a fluid flowing into the reservoir from a supply source; and an elastically deformable seal member sealing the fluid chamber, wherein, when the assisting piston is present at the location on the one side, the fluid chamber is partitioned into a first chamber and a second chamber, the first chamber communicating with the supply source, the second chamber communicating with the first chamber via a restricting flow path, and the seal member seals the second chamber.

2 . The hydraulic braking device according to claim 1 ,
wherein, when the assisting piston is present at the location on the one side and the fluid is flowing from the first chamber to the second chamber via the restricting flow path in response to elastic deformation of the seal member, the assisting piston starts moving from the location on the one side to the other side.

3 . The hydraulic braking device according to claim 1 ,
wherein, when the assisting piston is present at the location on the one side, the restricting flow path is formed between an end portion of the assisting piston and an end surface on the one side of the cylinder, the end surface facing the end portion.

4 . The hydraulic braking device according to claim 1 ,
wherein the seal member is annular and provided with a groove, the groove being opened to a side surface in contact with the fluid, the groove extending in a circumferential direction.

5 . The hydraulic braking device according to claim 1 ,
wherein the cylinder includes a tubular cylinder member and a plug, at least a part of the plug being housed in a tube of the cylinder member, at least a part of a cylindrical inner surface of the cylinder member faces the second chamber, and the seal member seals a gap between the cylinder member and the plug.

Assignees

• Advics Co Ltd

Inventors

• Yamaguchi Tomoyuki

Classifications

• B60T11/236

  Piston sealing arrangements · CPC title

• B60T13/745

  acting on a hydraulic system, e.g. a master cylinder · CPC title

• B60T13/686

  in hydraulic systems or parts thereof · CPC title

• B60T13/147

  In combination with distributor valve · CPC title

• B60T13/146

  Part of the system directly actuated by booster pressure · CPC title