Brake device for vehicle

Patent metadata

Field	Value
Publication number	US-9533665-B2
Application number	US-201314889737-A
Country	US
Kind code	B2
Filing date	May 8, 2013
Priority date	May 8, 2013
Publication date	Jan 3, 2017
Grant date	Jan 3, 2017

Abstract

A master cylinder includes pressurizing chambers and atmospheric pressure chambers which are in communication with a reservoir provided upstream. The pressurizing chambers of the master cylinder are connected to a brake fluid pressure control valve device through master pressure pipes provided with master cut valves. The atmospheric pressure chambers of the master cylinder bypass the master cut valves and are connected to the brake fluid pressure control valve device through bypass pipes provided with check valves. A pump constituting a brake fluid pressurizing section of the brake hydraulic control valve device suctions the brake fluid from the reservoir preferentially through the bypass pipes provided with the check valves and pressurizes the brake fluid to supply a brake fluid pressure to brake fluid pressure adjust sections.

First claim

The invention claimed is:

1. A brake device for a vehicle, comprising:
a reservoir for reserving operation fluid;
wheel cylinders for applying braking force to respective vehicle wheels of the vehicle by a pressure of the operation fluid;
a fluid pressure control valve mechanism for independently controlling the pressure of the operation fluid supplied to the respective wheel cylinders;
a master cylinder for generating the pressure of the operation fluid depending on an operation of a brake pedal;
at least one connection passage for connecting the master cylinder to the fluid pressure control valve mechanism;
at least one shut-off valve provided in the at least one connection passage;
at least one bypass passage which bypasses the at least one shutoff valve and cause the fluid pressure control valve mechanism to be in communication with the reservoir;
at least one one-way valve provided in the at least one bypass passage, the at least one one-way valve allowing only a flow of the operation fluid from the reservoir to the fluid pressure control valve mechanism;
a power-driven type fluid pressure source driven by a predetermined power to supply, to the fluid pressure control valve mechanism, the operation fluid having the pressure depending on the operation of the brake pedal; and
an electronic control unit for controlling an operation of the fluid pressure control valve mechanism and an operation of the power-driven type fluid pressure source,
the electronic control unit is programmed:
to maintain a state of the at least one shut-off valve at a state for shutting off a flow of the operation fluid from the master cylinder to the fluid pressure control valve mechanism when the brake pedal is operated; and
to maintain the state of the at least one shut-off valve at a state for allowing the flow of the operation fluid from the master cylinder to the fluid pressure control valve mechanism when the brake pedal is not operated,
wherein the master cylinder includes:
at least one pressurizing chamber in which the operation fluid is pressurized by at least one pressurizing piston which moves in conjunction with the operation of the brake pedal; and
at least one atmospheric pressure chamber for maintaining the pressure of the operation fluid at the atmospheric pressure,
the at least one pressurizing chamber becomes in communication with the reservoir when the brake pedal is not operated,
the at least one atmospheric pressure chamber is in communication with the reservoir regardless of whether the brake pedal is operated,
the at least one connection passage includes the at least one pressurizing chamber, and
the at least one bypass passage includes the at least one atmospheric chamber.

2. The brake device for the vehicle according to claim 1 , wherein the power-driven type fluid pressure source is connected to a recirculation passage for recirculating the operation fluid to the reservoir in order to supply, to the fluid pressure control valve mechanism, the operation fluid having a pressure depending on the operation of the brake pedal, and
the at least one bypass passage includes the recirculation passage.

3. The brake device for the vehicle according to claim 2 , wherein the reservoir includes fluid chambers defined by a partition wall, and the recirculation passage is in communication with one of the fluid chambers.

4. The brake device for the vehicle according to claim 1 , wherein the brake device comprises brake systems for supplying the operation fluid to the respective wheel cylinders,
the at least one connection passage comprises a plurality of connection passages,
the connection passages are provided corresponding to the respective brake systems,
the reservoir includes fluid chambers defined by a partition wall,
the at least one bypass passage comprises a plurality of bypass passages, and
the bypass passages are provided corresponding to the respective connection passages and are in communication with the respective fluid chambers of the reservoir.

5. The brake device for the vehicle according to claim 1 , wherein the at least one one-way valve includes a spherical valve body and a valve seat,
the at least one one-way valve is closed by the valve body seating on the valve seat and is opened by the valve body moving away from the valve seat, and
the at least one one-way valve is provided in the at least one bypass passage such that the valve body is caused to seat on the valve seat by the gravity.

6. A brake device for a vehicle, comprising:
a reservoir for reserving operation fluid;
wheel cylinders for applying braking force to respective vehicle wheels of the vehicle by a pressure of the operation fluid;
a fluid pressure control valve mechanism for independently controlling the pressure of the operation fluid supplied to the wheel cylinders;
a master cylinder for generating the pressure of the operation fluid depending on an operation of a brake pedal;
at least one connection passage for connecting the master cylinder to the fluid pressure control valve mechanism;
at least one shut-off valve provided in the at least one connection passage;
at least one bypass passage which bypasses the at least one shutoff valve and cause the fluid pressure control valve mechanism to be in communication with the reservoir;
at least one one-way valve provided in the at least one bypass passage, the at least one one-way valve allowing only a flow of the operation fluid from the reservoir to the fluid pressure control valve mechanism;
a power-driven type fluid pressure source driven by a predetermined power to supply, to the fluid pressure control valve mechanism, the operation fluid having the pressure depending on the operation of the brake pedal; and
an electronic control unit for controlling an operation of the fluid pressure control valve mechanism and an operation of the power-driven type fluid pressure source,
the electronic control unit is programmed:
to maintain a state of the at least one shut-off valve at a state for shutting off a flow of the operation fluid from the master cylinder to the fluid pressure control valve mechanism when the brake pedal is operated; and
to maintain the state of the at least one shut-off valve to a state for allowing the flow of the operation fluid from the master cylinder to the fluid pressure control valve mechanism when the brake pedal is not operated,
wherein the power-driven type fluid pressure source is connected to a recirculation passage for recirculating the operation fluid to the reservoir in order to supply, to the fluid pressure control valve mechanism, the operation fluid having a pressure depending on the operation of the brake pedal, and
the at least one bypass passage includes the recirculation passage.

7. The brake device for the vehicle according to claim 6 , wherein the brake device comprises brake systems for supplying the operation fluid to the respective wheel cylinders,
the at least one connection passage comprises a plurality of connection passages,
the connection passages are provided corresponding to the respective brake systems,
the reservoir includes fluid chambers defined by a partition wall,
the at least one bypass passage comprises a plurality of bypass passages, and
the bypass passages are provided corresponding to the respective connection passages and are in communication with the respective fluid chambers of the reservoir.

8. The brake device for the vehicle according to claim 6 , wherein the reservoir includes fluid chambers defined by a partition wall, and the recirculation passage is in communication with one of the fluid chambers.

9. The brake device for the vehicle according to claim 6 , wherein the at least one on

Assignees

• Nimura Kazunori
• Nakaoka Hiroshi
• Toyota Motor Co Ltd

Inventors

• Nimura Kazunori
• Nakaoka Hiroshi

Classifications

• B60T7/042

  by electrical means, e.g. using travel or force sensors · CPC title

• B60T13/686 Primary

  in hydraulic systems or parts thereof · CPC title

• B60T8/38

  including valve means of the relay or driver controlled type · CPC title

• B60T13/58

  Combined or convertible systems · CPC title

• B60T2270/604

  Merging friction therewith; Adjusting their repartition · CPC title