US 6,883,545 B2 · Three-way switching valve

Abstract

The object of the present invention is to provide a three-way switching valve having a valve mechanism compact in size, and capable of changing a flow of a high-pressure fluid, without internal leakage of the fluid. A compact pilot-operated three-way switching valve changes a flow of a fluid introduced into an inlet port such that the fluid is caused to flow into a first outlet port or a second outlet port. Pressures in pressure-regulating chambers above pistons are selectively guided into a passage by a pilot valve having a pilot valve element, plugs including respective valve seats, and a spring. The passage leads one of the pressures to the first outlet port or the second outlet port via a check valve having valve, and a valve element. The check valve causes a very small amount of fluid permitted to flow so as to keep main valves open and closed, respectively, to flow to the downstream side of an open one of the main valves, whereby internal leakage of fluid is prevented.

Drawings

Claims14

Dependent claims

A pilot-operated three-way switching valve for changing a flow of a fluid introduced into an inlet port such that the fluid is caused to flow into a first outlet port or a second outlet port,

characterized in that between a pilot valve for carrying out switching operation to cause one of respective pressure-regulating chambers for two pistons interlocked with two main valves to communicate with a low-pressure side, and the first outlet port and the second outlet port located on downstream sides of the main valves, there is provided a check valve that operates such that the pilot valve and a downstream side of an open one of the main valves are communicated with each other by a differential pressure between a pressure on a pilot valve side and a pressure on a downstream side of a closed one of the main valves.

A three-way switching valve for changing a flow of a fluid introduced into an inlet port such that the fluid is caused to flow into a first outlet port or a second outlet port,

characterized by comprising:
a first main valve disposed between the inlet port and the first outlet port, for opening and closing therebetween;
a second main valve disposed between the inlet port and the second outlet port, for opening and closing therebetween;
a first piston having a larger pressure-receiving area than that of a first main valve element of the first main valve, and operating in conjunction with the first main valve element in directions of opening and closing operations of the first main valve element;
a second piston having a larger pressure-receiving area than that of a second main valve element of the second main valve, and operating in conjunction with the second main valve element in directions of opening and closing operations of the second main valve element;
a check valve disposed between the first outlet port and the second outlet port, for operation such that a passage leading to a downstream side of a closed one of the first and second main valves is closed;
a pilot valve for carrying out switching operation to selectively communicate the check valve with respective pressure-regulating chambers for the first piston and the second piston;
and
a solenoid for actuating a pilot valve element of the pilot valve to switch the pilot valve.

6 more elements

Dependencies are inferred from the claim text.

Description6,380 words

Summary738 words

#This application claims priority of Japanese Application No. 2002-172823 filed on Jun. 13, 2002 and entitled “Three-Way Switching Valve”.

#(1) Field of the Invention

#This invention relates to a three-way switching valve, and more particularly to a pilot-operated three-way switching valve for switching a flow path of a fluid through electromagnetic operation.

Brief description of the drawings7 figures

#FIG. 1 is cross-sectional views showing the internal construction of a three-way switching valve according to a first embodiment of the invention, in a state with its solenoid being OFF.

#FIG. 2 is cross-sectional views showing the internal construction of the three-way switching valve according to the first embodiment, in a state with its solenoid being ON.

#FIG. 3 is a time chart showing operating conditions of the three-way switching valve according to the first embodiment.

Detailed description5,479 words

#Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

#FIG. 1 provides cross-sectional views showing the internal construction of a three-way switching valve according to a first embodiment, in a state with its solenoid being OFF. FIG. 2 provides cross-sectional views showing the internal construction of the three-way switching valve according to the first embodiment, in a state with its solenoid being ON. FIG. 3 is a time chart showing operating conditions of the three-way switching valve according to the first embodiment.

#The three-way switching valve has a body 1 through which two cylinder bores 2, 3 are formed for accommodating two main valves in parallel with each other on the left side and right side thereof as viewed in FIGS. 1 and 2. The body 1 has an inlet port T1 formed in the center thereof, for introducing a fluid such that the inlet port T1 communicates with both of the cylinder bores 2, 3. At respective locations downward of the cylinder bores 2, 3 are formed a first outlet port T2 and a second outlet port T3.

Facts

Application

10/457,540Filed 10 Jun 2003

Priority

JP 2002-17282313 Jun 2002

Published

US 2003/0230347 A118 Dec 2003

Granted

26 Apr 2005

Term ended

21 Oct 2023

Estimated · how

20 years from earliest known nonprovisional domestic filing plus recorded patent term adjustment, including 133 days of adjustment. Maintenance-fee lapses, terminal disclaimers and statutory extensions have not been checked. The continuity chain may be incomplete; this is not an enforceability determination.

Classification5 codes

F16K 31/42
Actuated by fluid: by means of electrically-actuated members in the supply or discharge conduits of the fluid motor
F16K 31/406
With electrically-actuated member in the discharge of the motor: acting on a piston
Y10T 137/87893
With flow control means for branched passages: with fluid actuator
F16K
Valves

Timeline

13 Jun 2002Priority claimedJP 2002-172823
10 Jun 2003Application filedUS 10/457,540
10 Jun 2003Assigned to Tgk Co., Ltd.assignment of assignor's interest
18 Dec 2003PublishedUS 2003/0230347 A1
26 Apr 2005GrantedUS 6,883,545 B2
21 Oct 2023Term endedEstimated, includes 133 days of adjustment

Three-way switching valve

Life of this patent

Three-way switching valve

Life of this patent

Life of this patent

Abstract

Drawings

Drawings

Claims14

Description6,380 words

Drawings

Classification5 codes

Life of this patent

Description6,380 words