Pressure regulator and hydraulic brake system for vehicle equipped with the same

Patent metadata

Field	Value
Publication number	US-9829114-B2
Application number	US-201514810976-A
Country	US
Kind code	B2
Filing date	Jul 28, 2015
Priority date	Aug 21, 2014
Publication date	Nov 28, 2017
Grant date	Nov 28, 2017

Abstract

A pressure regulator configured to regulate a pressure of a working fluid by two pilot pressures, including: a spool valve mechanism having a spool; a first biasing mechanism configured to bias the spool toward the other end of the pressure regulator in its axial direction by a first pilot pressure in a first-pilot-pressure chamber; a second biasing mechanism configured to bias the spool toward the other end of the pressure regulator by a second pilot pressure in a second-pilot-pressure chamber; and a counter biasing mechanism configured to bias the spool toward one end of the pressure regulator by a pressure of the working fluid in a regulated-pressure chamber, wherein the counter biasing mechanism has a counter biasing piston configured to push the spool toward the one end of the pressure regulator by the pressure of the working fluid in the regulated-pressure chamber applied to the counter biasing piston.

First claim

What is claimed is:

1. A pressure regulator configured to regulate a pressure of a working fluid supplied from a high-pressure source, to a regulated pressure by two pilot pressures and configured to supply the pressure-regulated working fluid, comprising:
a housing;
a high-pressure port to which is supplied the working fluid supplied from the high-pressure source, a low-pressure port which is to communicate with a low-pressure source, and a regulated-pressure port for supplying the pressure-regulated working fluid, the high-pressure port, the low-pressure port, and the regulated-pressure port being provided on the housing;
a spool valve mechanism provided in the housing and having a spool configured to be movable in an axial direction of the pressure regulator, the spool valve mechanism being configured such that, (i) when the spool is located at an end position in a movable range of the spool, the end position being nearer to one end of the pressure regulator in the axial direction, communication between the low-pressure port and the regulated-pressure port is allowed while communication between the high-pressure port and the regulated-pressure port is shut off, and (ii) when the spool is moved toward the other end of the pressure regulator in the axial direction, the communication between the low-pressure port and the regulated-pressure port is shut off while the communication between the high-pressure port and the regulated-pressure port is allowed;
a first biasing mechanism provided in the housing on one of opposite sides of the spool nearer to the one end of the pressure regulator and having a first-pilot-pressure chamber to which is introduced a working fluid having a first pilot pressure that is one of the two pilot pressures, the first biasing mechanism being configured to bias the spool toward the other end of the pressure regulator by the pressure of the working fluid in the first-pilot-pressure chamber;
a second biasing mechanism provided in the housing on the one of the opposite sides of the spool nearer to the one end of the pressure regulator and having a second-pilot-pressure chamber to which is introduced a working fluid having a second pilot pressure that is the other of the two pilot pressures, the second biasing mechanism being configured to bias the spool toward the other end of the pressure regulator by the pressure of the working fluid in the second-pilot-pressure chamber; and
a counter biasing mechanism provided in the housing on the other of the opposite sides of the spool nearer to the other end of the pressure regulator and having a regulated-pressure chamber which communicates with the regulated-pressure port and to which is introduced the working fluid having the regulated pressure, the counter biasing mechanism being configured to bias the spool toward the one end of the pressure regulator by the pressure of the working fluid in the regulated-pressure chamber,
wherein the counter biasing mechanism has a counter biasing piston provided on the other of the opposite sides of the spool and configured to push the spool toward the one end of the pressure regulator by the pressure of the working fluid in the regulated-pressure chamber applied to the counter biasing piston.

2. The pressure regulator according to claim 1 ,
wherein, when the first biasing mechanism biases the spool, the second biasing mechanism is prohibited from biasing the spool, and
wherein, when pressure regulation by the first pilot pressure is disabled from biasing the spool, the second biasing mechanism is allowed to bias the spool.

3. The pressure regulator according to claim 1 , wherein the first biasing mechanism and the second biasing mechanism are disposed in series, and the second biasing mechanism is configured to bias the spool toward the other end of the pressure regulator via a pilot piston of the first biasing mechanism.

4. The pressure regulator according to claim 1 , wherein the first biasing mechanism has a first pilot piston disposed on the one of opposite sides of the spool nearer to the one end of the pressure regulator, the first pilot piston being configured to push the spool toward the other end of the pressure regulator by the pressure of the working fluid in the first-pilot-pressure chamber applied to the first pilot piston.

5. The pressure regulator according to claim 4 ,
wherein the first pilot piston has a rod portion that extends toward the other end of the pressure regulator, and the spool has a blind hole that is open at one end portion thereof nearer to the one end of the pressure regulator, and
wherein the rod portion is configured such that a distal end thereof is to engage with the spool at a bottom wall of the blind hole.

6. The pressure regulator according to claim 5 , wherein the bottom wall of the blind hole has a tapered shape, and the distal end of the rod portion of the first pilot piston has a curved convex shape.

7. The pressure regulator according to claim 1 , further comprising a counter-biasing restraining mechanism having a restraining-pressure chamber which communicates with the first-pilot-pressure chamber and to which the working fluid having the first pilot pressure is introduced, the counter-biasing restraining mechanism being configured to restrain the counter biasing mechanism from biasing the spool toward the one end of the pressure regulator, by the pressure of the working fluid in the restraining-pressure chamber.

8. A hydraulic brake system for a vehicle, comprising:
a brake operation member;
a brake device provided for a wheel of the vehicle;
a master cylinder device to which is introduced the pressure-regulated working fluid, the master cylinder device being configured to pressurize a working fluid to a pressure in accordance with a pressure of the working fluid introduced thereto and configured to supply the pressurized working fluid to the brake device;
a high-pressure-source device, as the high-pressure source, configured to supply a working fluid having a high pressure;
a pressure adjusting device configured to be controlled so as to adjust a pressure of a working fluid to a given pressure; and
the pressure regulator defined according to claim 1 ,
wherein the working fluid whose pressure is adjusted by the pressure adjusting device is introduced to the first-pilot-pressure chamber of the pressure regulator as the working fluid having the first pilot pressure,
wherein one of a working fluid having a pressure in accordance with a brake operation force applied to the brake operation member and the working fluid supplied from the master cylinder device to the brake device is introduced to the second-pilot-pressure chamber of the pressure regulator as the working fluid having the second pilot pressure, and
wherein the working fluid whose pressure is regulated by the pressure regulator is introduced to the master cylinder device.

Assignees

• Toyota Motor Co Ltd

Inventors

• Isono Hiroshi

Classifications

• B60T13/146

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

• F16K11/06

  comprising only sliding valves {, i.e. sliding closure elements} · CPC title

• F16K17/0473 Primary

  Multiple-way safety valves · CPC title

• B60T13/167

  In combination with distributor valve · CPC title

• B60T13/686

  in hydraulic systems or parts thereof · CPC title