HYDRAULIC BRAKE SYSTEM

• US 20170096131A1
• Filed: 10/05/2016
• Published: 04/06/2017
• Est. Priority Date: 10/05/2015
• Status: Active Grant

• Current Assignee: HL Mando Corporation (Halla Holdings Corporation)
• Original Assignee: Mando Corporation
• Inventors: SONG, Min-Geun
• Granted Patent: US 9,969,372 B2
• Time in Patent Office: Days
• CPC Class Codes: B60T 8/4068 the additional fluid circuit comprising means for attenuating pressure pulsations
• CPC Class Codes: B60T 8/4872 pump-back systems

Abstract

Disclosed herein is a hydraulic brake system. The hydraulic brake system comprises a damping device configured to attenuate pressure pulsation of brake oil discharged according to a driving of a pump, wherein the damping device includes a sleeve fixed to a bore that is connected to a discharge end of the pump and having an opened one side, a damping piston slidably installed inside the sleeve, and an elastic member provided inside the sleeve and configured to elastically support the damping piston, and wherein a slot having a width which is varied is formed at an inner circumferential surface of the sleeve in a direction in which the brake oil flows so that a variable orifice is formed between the damping piston and the sleeve.

Claims

1. A hydraulic brake system comprising:

a damping device configured to attenuate pressure pulsation of brake oil discharged according to a driving of a pump,

wherein the damping device includes;

a sleeve fixed to a bore that is connected to a discharge end of the pump and having an opened one side;

a damping piston slidably installed inside the sleeve; and

an elastic member provided inside the sleeve and configured to elastically support the damping piston, and

wherein a slot having a width which is varied is formed at an inner circumferential surface of the sleeve in a direction in which the brake oil flows so that a variable orifice is formed between the damping piston and the sleeve.

2. The hydraulic brake system of claim 1, wherein a cross-sectional area of the variable orifice at which the brake oil passes through is gradually increased toward a direction in which the brake oil is discharged.

3. The hydraulic brake system of claim 1, wherein the damping piston is provided to be moved to pressurize the elastic member when hydraulic pressure of the brake oil discharged from the pump is equal to or greater than a predetermined pressure.

4. The hydraulic brake system of claim 1, wherein the damping piston includes a flange having an outer circumferential surface at one side thereof, which is moved along the inner circumferential surface of the sleeve.

5. The hydraulic brake system of claim 1, wherein the damping piston is provided in a cylindrical shape and with a flange protruding at one side of the cylindrical shape, and the elastic member is provided at an outward side of the cylindrical shape and one side of the elastic member is supported at the flange.

6. The hydraulic brake system of claim 1, wherein the elastic member is configured with a damping spring of a coil shape.

7. The hydraulic brake system of claim 1, wherein the elastic member is configured with a damping tube at which a damping space is formed thereinside.

8. The hydraulic brake system of claim 7, wherein the damping tube is configured with a rubber material to be elastically deformed by pressurization of the damping piston.

9. The hydraulic brake system of claim 1, further comprising a first stopper coupled to the opened one side of the sleeve and configured to support the elastic member and limit a movement distance of the damping piston.

10. The hydraulic brake system of claim 9, wherein a first coupling depression is formed at an outer circumferential surface of the sleeve, and

the first stopper includes:

a body configured to expose a portion of an opened aperture of the sleeve; and

a plurality of rods formed to be bended and to extend from the body to be coupled to the first coupling depression.

11. The hydraulic brake system of claim 10, wherein the first coupling depression is configured with a circular depression formed along the outer circumferential surface of the sleeve, and each of the plurality of rods is provided with a coupling protrusion that is bended toward the first coupling depression to be fit thereinto.

12. The hydraulic brake system of claim 5, further comprising:

a first stopper coupled to the opened one side of the sleeve to limit a movement distance of the damping piston,

wherein one side of the elastic member is supported at the flange and the other end of the elastic member is supported at the first stopper, and

an end portion of the cylindrical shape of the damping piston is disposed to be spaced apart from the first stopper.

13. The hydraulic brake system of claim 9, wherein the sleeve is provided to have an opened one side, and

the hydraulic brake system further includes:

a second stopper coupled to the other side of the sleeve and configured to support the damping piston and limit a movement distance thereof.

14. The hydraulic brake system of claim 13, wherein a second coupling depression is formed at an outer circumferential surface of the sleeve, and

the second stopper includes:

a body configured to expose a portion of an opened aperture of the sleeve; and

a plurality of rods formed to be bended and to extend from the body to be coupled to the second coupling depression.

15. A hydraulic brake system comprising:

a first hydraulic circuit configured to connect a first port of a master cylinder to a first wheel cylinder to control delivery of hydraulic pressure;

a second hydraulic circuit configured to connect a second port of the master cylinder to a second wheel cylinder to control delivery of hydraulic pressure;

a pump configured to suction brake oil from the master cylinder and pump the suctioned brake oil;

a main flow path configured to connect a discharge outlet of the pump to the master cylinder;

an auxiliary flow path configured to guide the brake oil to an inlet of the pump to enable the brake oil to be suctioned; and

a damping device installed at the main flow path and configured to attenuate pressure pulsation of the brake oil discharged according to a driving of the pump,

wherein the damping device includes;

a sleeve fixed to a bore that is connected to a discharge end of the pump and having an opened one side;

a damping piston slidably installed inside the sleeve; and

an elastic member provided inside the sleeve and configured to elastically support the damping piston, and

wherein a slot having a width that is varied in a direction in which the brake oil flows is formed at an inner circumferential surface of the sleeve to form a variable orifice between the damping piston and the sleeve.