Piston pump for brake system

Patent metadata

Field	Value
Publication number	US-11181102-B2
Application number	US-201816058357-A
Country	US
Kind code	B2
Filing date	Aug 8, 2018
Priority date	Aug 8, 2017
Publication date	Nov 23, 2021
Grant date	Nov 23, 2021

Abstract

Disclosed is a piston pump for a brake system installed in a bore of a modulator block communicating with an inlet port and a discharge port, wherein the piston pump includes: a cylinder unit provided to reciprocate within the bore; a piston unit having one end fixed and the other end dividing the inside of the cylinder unit into a first chamber and a second chamber and configured to expand or reduce the internal spaces of the first chamber and the second chamber by reciprocating movement of the cylinder unit; a first inlet valve installed in the cylinder unit to open and close an one-way flow of fluid from the inlet port to the first chamber; a second inlet valve installed in the cylinder unit to open and close an one-way flow of fluid from the inlet port to the second chamber; and an outlet valve to open and close an one-way flow of fluid from the first chamber or the second chamber to the discharge port.

First claim

What is claimed is:

1. A piston pump for a brake system installed in a bore of a modulator block communicating with an inlet port and a discharge port, the piston pump comprising:
a cylinder unit provided to reciprocate within the bore;
a piston unit having a first end fixed and a second end dividing an inside of the cylinder unit into a first chamber and a second chamber and configured to expand or reduce the internal spaces of the first chamber and the second chamber by reciprocating movement of the cylinder unit;
a first inlet valve installed in the cylinder unit to open and close a one-way flow of fluid from the inlet port to the first chamber;
a second inlet valve installed in the cylinder unit to open and close a one-way flow of fluid from the inlet port to the second chamber; and
an outlet valve to open and close a one-way flow of fluid from the first chamber or the second chamber to the discharge port,
wherein the piston unit includes:
a piston provided with a flow passage hole communicatively connected with a discharge chamber;
a piston seal configured to be movable together with the cylinder unit along an outer circumferential surface of the piston to selectively communicate the flow passage hole with one of the first chamber and the second chamber;
a piston head at the second end of the piston unit and a first discharge passage defined by the piston head and an inner surface of the cylinder unit; and
a piston guide guiding the movement of the cylinder unit along the outer circumferential surface of the piston and having a second discharge passage,

the piston seal is in contact with the outer circumferential surface of the piston, and
the piston seal is configured to be movable between the piston head and the piston guide.

2. The piston pump for a brake system according to claim 1 , wherein the piston unit further includes a stopper for preventing the separation of the piston guide.

3. The piston pump for a brake system according to claim 1 , wherein a first inflow passage is formed on a surface of the cylinder unit facing the inlet port, the first inlet valve provided with a power transmitting member receiving a forward or backward force by an eccentric spindle is coupled to an opening of one end of the cylinder unit, and the second inlet valve is coupled to an opening of the other end of the cylinder unit.

4. The piston pump for a brake system according to claim 1 ,
wherein the first inlet valve includes a power transmitting member receiving a forward force or a backward force by an eccentric spindle, and having a first inlet passage and a seat surface on which a first opening and closing member is seated, and a first elastic member supported at one end to a retainer fastened to the power transmitting member to provide an elastic force to the first opening and closing member.

5. The piston pump for a brake system according to claim 1 ,
wherein the second inlet valve includes a second elastic member supported at one end to the cylinder unit, a second opening and closing member pressed by the other end of the second elastic member, a second guide member guiding the piston unit and provided with a second inlet passage opened and closed by the second opening and closing member, and a second stopper member provided with a second inflow passage and preventing the second guide member from being separated.

6. The piston pump for a brake system according to claim 1 ,
wherein the outlet valve includes an outlet valve seat to which the piston unit is fixedly installed, an outlet cap coupled to the outlet valve seat to form a discharge chamber communicating with the discharge port, an outlet opening and closing member to press a flow passage of the outlet valve seat communicating with a flow passage hole of the piston unit, and an outlet elastic member supported to the outlet cap and providing an elastic force to the outlet opening and closing member.

7. The piston pump for a brake system according to claim 2 ,
wherein the stopper is coupled to the outer circumferential surface of the piston.

Assignees

• Mando Corp

Inventors

• Lee Chung Jae

Classifications

• F04B53/1002

  Ball valves · CPC title

• B60T8/4018

  Pump units characterised by their drive mechanisms (B60T8/4095 takes precedence) · CPC title

• B60T8/4031 Primary

  Pump units characterised by their construction or mounting (pump units in combination with valve blocks B60T8/36) · CPC title

• F04B1/02 Primary

  having two cylinders (in V-arrangement F04B1/04) · CPC title

• F04B1/0452

  Distribution members, e.g. valves (machines or pumps with cam-actuated distribution members at the outer ends of the cylinders F04B1/0472; machines or pumps with cam-actuated distribution members at the inner ends of the cylinders F04B1/0531; the piston-driving cams being provided with inlets and outlets F04B1/0535) · CPC title