JPH10325476A - Selector valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent leakage of fluid at a selecting by cut-off part for a valve flow passage, in a multiport selector valve. SOLUTION: A selector valve comprises a valve housing 1; a valve element 2; and a floating ring member 3. A valve element in the outer periphery surface of which a floating ring member is axially movably fitted is axially movably fitted together with a floating ring member. Contact parts 17 and 19 making contact with the inner peripheral area of the end face of a floating ring member are arranged in a manner to regulate the axial relative movement range of the valve element to the floating ring member are arranged at the valve element. A contact part with which the outer peripheral area of the end face of a floating ring member makes contact to regulate the axial movement range of a floating ring member through axial movement of the valve element is arranged on the inner peripheral surface of a valve housing. An inner valve passage is switched through contact and separation between the contact part of the valve element and the inner peripheral of the end face of the floating ring member through axial movement operation of the valve element and through contact and separation between the contact part of the valve housing and the inner peripheral area of the end face of the floating ring member.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a switching valve used in a hydraulic circuit for oil, air, or the like.

[0002]

2. Description of the Related Art A switching valve is used for switching the circuit configuration of a fluid circuit such as oil or air. The switching valve includes a valve housing to which a plurality of fluid conduits / passages (hereinafter, referred to as a fluid passage) are connected, and a valve shaft member fitted in the valve housing so as to be movable in an axial direction. By changing the axial position of the valve shaft member with respect to the valve housing according to the relationship between the outer peripheral shape of the member and the inner peripheral shape of the valve housing, the conduction relationship between the plurality of fluid flow paths introduced into the valve housing changes. This valve shaft member is operated by means of operating means (for example, changing the axial position with respect to the valve housing by using a solenoid of a solenoid valve, a lever or button of a manually operated valve, a cam or a link mechanism of a mechanically operated valve). Thus, the switching control of the intended circuit configuration is realized.

[0003] As a basic structural principle of a switching valve for switching a circuit configuration according to the axial position of the valve shaft member, a "poppet valve type" and a "spool valve type" are known. FIG. 6 shows a structure of a spool valve type 2-position 4-port switching valve. The spool valve 100 has four ports 13
Valve housing 11 with 1,132,133,134
0, and a spool 150 that slides in a fluid passage 120 in the valve housing 110. The spool 150 has two land portions 151 and 152 and land portions 151 and 152.
Has annular groove portions 153, 154, 155 arranged on both sides of the. In the state of FIG. 4, the port 131 and the port 134 are connected, and the port 132 and the port 133 are connected. When the spool 150 is moved in the direction of arrow R in the figure, the land 151 closes the inner peripheral portion 122 of the fluid passage 120. By this operation, the port 131 communicates with the port 133, and the port 132 communicates with the port 134.

FIG. 7 shows the structure of a poppet type two-position three-port switching valve. The poppet valve 200 has three ports 2
A housing 210 having 11, 212, 213 and a spool 25 sliding within a fluid passage 220 in the housing
0 is provided. The spool 250 has a land portion 251,
The land portion 251 is connected to the fluid passage 220 of the housing 210.
Are selectively brought into contact with the wall surfaces 221 and 222 for partitioning.

In the state shown in FIG. 7, the ports 211 and 213 communicate with each other. In FIG. 6, the spool 250
Is moved in the direction of arrow L, the land 251 is moved to the wall surface 221.
And the port 212 and the port 213 are communicated. In this poppet valve, the shut-off mechanism between the fluid circuits is added to the axial contact between the members by the operating means of the valve shaft member, and in some cases, the pressure of the fluid is applied to the contact between the members so that the contact force is increased. The self-sealing effect that strengthens
There is an advantage that a substantially complete shut-off state can be configured. This type of poppet valve is disclosed, for example, in Japanese Patent Application Laid-Open No. 60-196471.

[0006]

In the above "spool valve type" switching valve, the number of ports is not limited.
It is possible to realize a conductive relationship between various fluid flow paths. For example, as shown in FIG. 5, even in a hydraulic circuit, a two-position four-port switching exemplified in FIG. 6 which is a typical spool valve type switching valve By using one valve, the flow path of the hydraulic circuit can be easily controlled. However, in the spool valve type, each fluid circuit is separated from each other by a fitting area of a land portion between the inner peripheral surface of the valve housing and the outer peripheral surface of the valve shaft member, which are present between the annular grooves. The diameter of the part requires a minimum clearance to allow axial sliding of the valve stem relative to the valve housing.

For this reason, it is impossible to completely shut off the electrical connection between the fluid flow paths. In particular, when the pressure difference between the adjacent fluid flow paths is large, these fluid flow paths are separated from each other. There is a disadvantage that the fluid leaks from the high pressure side to the low pressure side through the gap in the fitting area of the land. Therefore, in a system that does not like the leakage flow between the fluid flow paths, the spool valve type cannot be adopted, and it is necessary to use a poppet valve type. That is, when a two-position three-port switching valve exemplified in FIG. 7 which is a typical poppet valve type switching valve is used, the cutoff state of the fluid connection between the fluid flow paths is determined in the axial direction between the valve shaft member and the valve housing. (At the opening surface of the fluid flow path), a complete shut-off state is realized.

However, due to the principle that the shut-off state is constituted by the axial contact between the valve members, the structure in which two or more contact portions in the axial direction of both valve members are completely brought into contact at the same time is a structure of the valve member. It is difficult to work, and even if it is realized, the productivity is low and the production cost increases,
As shown in FIG. 7, the number of ports of the fluid flow path that can be switched by the movement of one valve shaft member is limited to three ports. If a plurality of contact portions of both valve members are not completely brought into contact at the same time, there is no advantage over the spool valve type.

However, if there are three ports, for example, FIG.
As shown in FIG. 7, also in the hydraulic circuit, it is necessary to use two two-position three-port switching valves exemplified in FIG. 7, and the hydraulic circuit itself becomes complicated, so that the production cost and the number of maintenance and inspection are required as compared with the case of the spool valve type. Leads to an increase in SUMMARY OF THE INVENTION An object of the present invention is to provide a switching valve in which the disadvantages of the spool valve type and the poppet valve type as described above in the switching valve are eliminated at once.

[0010]

The gist of the present invention is that a valve shaft member having a floating ring member fitted on its outer peripheral surface so as to be movable in the axial direction is shared with the floating ring member so as to be movable in the axial direction within the valve housing. It is at the point of fitting. That is, the switching valve of the present invention includes, as basic means, a housing member, a valve shaft member movable in the axial direction within a housing member provided inside the housing member, and a valve shaft member movable in the axial direction. A floating ring-shaped member fitted outside, a main valve chamber and a sub-valve chamber inside the housing member and partitioned by a partition, and first and second chambers at both ends in the main valve chamber and partitioned by a valve shaft member. A third chamber and a second chamber at an intermediate portion, a pressure fluid supply port formed on a wall of the housing member of the second chamber, a first circulation port formed on a wall of the housing member of the first chamber, and a housing of the third chamber. A second communication port formed in the member wall surface, a discharge port formed in the housing member wall surface of the sub-valve chamber, and a passage communicating the main valve chamber and the sub-valve chamber formed in the valve shaft member are provided. Then, by the axial movement of the valve shaft member and the floating ring member, one of the first or second flow ports is switched to a position communicating with the pressure fluid supply port and the other is communicated with the discharge port.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A switching valve according to an embodiment of the present invention will be described with reference to the drawings. The up, down, left, and right directions in the following description are directions in each drawing. The switching valve according to the embodiment of the present invention is a poppet valve type 2 position 4
The working fluid to be controlled by the port switching valve is a gas or a fluid, and will be described as oil in the following description.
The switching valve is used, for example, in a fluid pressure circuit shown in FIG. In the hydraulic circuit shown in FIG. 5, a poppet valve type two-position four-port switching valve V includes a double-acting cylinder A as an actuator and a pump P ·
It is connected to the oil tank T by pipelines L1 to L4.

A two-position four-port switching valve according to a first embodiment shown in FIGS. 1 and 2 includes a valve housing 1, a valve body 2 slidably fitted in the valve housing 1, and a valve body 2. And a floating ring member 3 which is slidably fitted on the outer peripheral surface. The valve housing 1 is formed with a hollow hole surrounded by a peripheral wall portion 4 and end wall portions 5 and 5 at both ends, and the valve chamber is divided into a main valve chamber and a sub-valve chamber 8 blocked by an intermediate wall section 6. The main valve chamber is divided into a first chamber 9 on the side of the end wall 5, a third chamber 10 on the side of the intermediate wall 6, and a second chamber 11 in the middle.

The peripheral wall portion 4 has a first communication port 12 communicating from the outside with the first chamber, a second communication port 13 also communicating with the third chamber 10, and a pressure fluid supply port 14 communicating with the second chamber 11. The peripheral wall portion 4 further penetrates a discharge port 15 that communicates with the auxiliary valve chamber 8 from outside.

The pressure fluid supply port 14 is provided with a pipeline L from a pump P which is a hydraulic oil supply source of a hydraulic circuit shown in FIG.
1 is connected, and the outlet 15 is also connected to a pipeline L2 to the oil tank T. Further, a pipe L3 from one port a of a double-acting cylinder A which is an actuator of a hydraulic circuit shown in FIG.
The second distribution port 13 also has a pipe L from the other port b.
4 are connected.

The valve stem member 2 comprises a first valve stem 16, a first flange 17, a cylindrical intermediate portion 18, a second flange 19, and a second valve stem 20, and a first chamber 9 and a second valve stem 20. The first flange portion 17 and the second flange portion 19 having a smaller diameter than the third chamber 10 are located in the main valve chamber, and the first valve stem 16 is slidably and oil-tight in the end wall 5 of the valve housing 1. And the second valve stem 20 projects through the intermediate wall 6 and the end wall 5 of the valve housing 1 in a slidable and oil-tight manner.
Operating means, for example, a solenoid of an electromagnetic valve (see FIG. 5), a lever of a manually operated valve, a cam for mechanical operation, a link mechanism, and the like are connected to the first valve stem 16.

A first annular groove 21 and a second annular groove 22 are formed on both ends of the intermediate portion 18 of the valve shaft member 2, and the center axis of the valve shaft member 2 is located on the end side of the second valve stem 20. Is formed to reach the first annular groove 21 from the center hole 23.
The opening end on the side of the second valve stem 20 is closed. In addition, a first communication hole 24 and a second communication hole 25 which respectively communicate the center hole 23 with the first annular groove 21 and the second annular groove 22 are formed, and the center hole 23 and the sub-valve chamber 8 are connected to each other. A third communication hole 26 that is always in communication is formed.

A floating ring member 3 shorter than the intermediate portion 18 is slidably fitted on the outer peripheral surface of the intermediate portion 18 of the valve shaft member 2, and the length of the floating ring member 3 is set at both ends of the intermediate portion 18. When it is located at the position, the length is such that it does not cover the first annular groove 21 or the second annular groove 22. Floating ring member 3
Is larger in diameter than the first and third chambers 10 by an appropriate amount, and is smaller in diameter by an appropriate gap 27 from the second chamber 11. Therefore, both end surfaces of the floating ring member 3 and both end surfaces of the second chamber 11 are formed with appropriate contact surfaces so that they can contact each other.

The operation of the two-position four-port switching valve of the first embodiment will be described. The valve shaft member 2 is configured such that the first valve rod 16 is operated by operating means, for example, a solenoid of a solenoid valve (see FIG. 5). The position is switched to the position shown in FIG. 1 and the position shown in FIG. When the valve stem member 2 moves leftward to the position shown in FIG. 1, the floating ring member 3 is pushed leftward by the second flange portion 19, and the outer peripheral area of the left end face of the floating ring member 3 becomes the second chamber 1.
1, while the inner peripheral area of the right end face is closely attached to the outer peripheral area of the left side face of the second flange portion 19,
The outer peripheral region of the right end surface of the floating ring member 3 is separated from the inner peripheral region of the right end surface of the second chamber 11, and the first flange portion 17 is
Move away from

As a result, the first chamber is cut off from the second chamber 11 by the floating ring member 3 and communicates with the first annular groove 21. Further, the second chamber 11 is shut off from the second annular groove 22 by the floating ring member 3 and the second flange 19. That is, in the position state of the valve body (see FIG. 1), the pressure fluid supply 14
Is the second through the gap 27, the second chamber 11 and the third chamber 10.
The communication port 13 is connected to the first communication port 12.
The outlet 15 is provided through the first chamber, the first annular groove 21, the first communication hole 24, the center hole 23, the third communication hole 26, and the auxiliary valve chamber 8.
Connected to

Thus, the hydraulic oil supplied from the hydraulic oil supply source of the hydraulic circuit (for example, the pump P in FIG. 5) via the line L1 flows in from the pressurized fluid supply 14 and the second flow port 13
Hydraulic oil that flows out of the hydraulic circuit and is supplied to the port b of the double-acting cylinder A, which is an actuator in the hydraulic circuit, through the pipe L4, and flows out of the port a of the double-acting cylinder A through the pipe L3. It flows in from one circulation port 12 and is discharged from the discharge port 15 to the oil tank T via the pipe line L2.
Thereby, one operation of the double-acting cylinder A is performed.

The hydraulic oil flowing from the above-described pressure fluid supply 14 flows into the third chamber 10 and faces the double-acting cylinder A. The hydraulic oil flowing from the first flow port 12 flows into the first chamber,
The third chamber 10 is on the high pressure side and the first chamber is on the low pressure side, and the differential pressure is applied to the second flange 19 and the floating ring member 3 to move the floating ring member 3 to the second chamber. 11
Of the floating ring member 3 as well as a pressing force for pressing the left end surface of the floating ring member 3.

Therefore, the pressing force for pressing the floating ring member 3 against the left end surface of the second chamber 11 and the pressing force for pressing the second flange portion 19 against the right end surface of the floating ring member are controlled by the valve shaft member 2 by the operating means. That is, the pressing force due to the above-described differential pressure is applied to the pressing force by the second flange portion 19, and the close contact between the outer peripheral area of the left end face of the floating ring member 3 and the inner peripheral area of the left end face of the second chamber 11 and the floating ring The close contact between the inner peripheral area of the right end face of the member 3 and the outer peripheral area of the left side face of the second flange 19 is further strengthened.

When the valve stem 2 moves rightward from the position shown in FIG. 1 to the position shown in FIG. 2, the valve stem 2 slides rightward with respect to the floating ring member 3 in the stationary state, and eventually the first flange. The part 17 contacts the floating ring member 3 and presses the floating ring member 3 to the right. Then, the outer peripheral area of the left end face of the floating ring member 3 is separated from the inner peripheral area of the left end face of the second chamber 11, and the outer peripheral area of the right end face is in close contact with the inner peripheral area of the right end face of the second chamber 11. The outer peripheral area of the right side surface of the 1 flange portion 17 is the floating ring member 3.
And the second flange 19 is separated from the floating ring member 3.

As a result, the first chamber 9 communicates with the second chamber 11 and the first chamber 17 is moved by the first flange 17 and the floating ring member 3.
It is cut off from the annular groove 21. Further, the third chamber 10 is isolated from the second chamber 11 by the floating ring member 3 and communicates with the second annular groove 22. That is, in the position state of the valve element, the pressure fluid supply 14 is connected to the first flow port 12 via the gap 27, the second chamber 11, and the first chamber, and the second flow port 13 is The third chamber 10, the second annular groove 22, the second communication hole 25, the center hole 23, the third communication hole 26, and the auxiliary valve chamber 8 are connected to the discharge port 15.

Thus, the hydraulic oil supplied from the hydraulic oil supply source of the hydraulic circuit (for example, the pump P in FIG. 5) via the line L1 flows in from the pressure fluid supply 14 and the first flow port 12
Hydraulic oil flowing out of the hydraulic circuit and supplied to the port a of the double-acting cylinder A in the hydraulic circuit via the line L3 and flowing out of the port b of the double-acting cylinder A flows through the second flow port 13 through the line L4. And is discharged from the discharge port 15 to the oil tank T via the pipe line L2. Thereby, the other operation of the double-acting cylinder A is performed.

For the same reason as in the case of the valve shaft member 2 on the left, the first chamber on the high-pressure side and the third chamber 1 on the low-pressure side.
Due to the pressure difference between 0 and 0, the outer peripheral area of the right end face of the floating ring member 3 is closely contacted with the inner peripheral area of the right end face of the second chamber 11 and the first flange 1
The close contact between the outer peripheral region on the right side of the inner ring 7 and the inner peripheral region on the left end surface of the floating ring member 3 becomes strong.

FIG. 3 shows another embodiment of the present invention. The switching valve 1a has a housing 4a. The switching valve 1a has a front end projecting into the sub-valve chamber 8 without the front end of the valve shaft member 2a protruding from the end wall 5a.
Is applicable when the working fluid is a liquid and the discharge port 15 is substantially at atmospheric pressure.

FIG. 4 shows another embodiment of the present invention. The switching valve 1b has a housing 4b. This housing 4
b does not have an auxiliary valve chamber, and the tip of the valve shaft member 2b projects from the partition wall 6a. In this switching valve, the center hole 23 of the valve shaft member 2b serves as a discharge port. This switching valve is applicable when the working fluid is air.

[0029]

According to the switching valve of the present invention, the valve body having the floating ring member fitted on the outer peripheral surface so as to be movable in the axial direction is fitted together with the floating ring member in the valve housing so as to be movable in the axial direction. Thus, the advantages unique to the poppet valve type are provided, and the flow path switching in the fluid flow path in the valve is performed at the axial contact surface, so that the flow path switching is completely performed. Done in

In addition, there is no difficulty in machining accuracy due to simultaneous contact of a large number of places, and it is possible to switch between multiple ports, which is an advantage unique to the spool valve type. That is, according to the present invention, it is possible to obtain a switching valve having only the advantages of the poppet valve type and the spool valve type and eliminating the disadvantages of both.

In particular, in the two-position four-port switching valve according to the second aspect, the first ring is divided by a floating ring member in the hollow portion of the valve housing by flowing from the inflow hole and discharging from the outflow hole. One of the hollow portions is on the high pressure side, the other hollow region is on the low pressure side, and the differential pressure acts on the contact portion of the floating ring member and the valve body, and as a pressing force for pressing the floating ring member against the fixed contact portion. work. Therefore, the pressing force for pressing the floating ring member is such that the pressing force due to the above-described differential pressure is applied to the pressing force by the operating means, and the close contact between the floating ring member and each contact portion is further strengthened.

[Brief description of the drawings]

FIG. 1 is a sectional view of a two-position four-port switching valve according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a two-position four-port switching valve according to the first embodiment of the present invention.

FIG. 3 is a sectional view of a two-position four-port switching valve according to a second embodiment of the present invention.

FIG. 4 is a sectional view of a two-position four-port switching valve according to a third embodiment of the present invention.

FIG. 5 is a hydraulic circuit diagram to which the two-position four-port switching valve according to the embodiment of the present invention is applied.

FIG. 6 is a cross-sectional view of a two-position four-port switching valve (spool valve type) according to a conventional technique.

FIG. 7 is a cross-sectional view of a two-position three-port switching valve (poppet valve type) according to a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Valve housing 2 Valve body 3 Floating ring member 4 Peripheral wall part 5 End wall part 6 Intermediate wall part 8 Sub-valve room 9 First room 10 Third room 11 Second room 12 First flow port 13 Second flow port 14 Pressure fluid Supply port 15 Discharge port 16 First valve stem 17 First flange 18 Intermediate portion 19 Second flange 20 Second valve stem 21 First annular groove 22 Second annular groove 23 Center hole 24 First communication hole 25 2 communication holes 26 3rd communication hole P pump T oil tank A double acting cylinder (actuator) a, b ports L1 to L4

Claims (2)

[Claims] A housing member, a valve shaft member provided inside the housing member, the valve shaft member being axially movable in a housing member, a floating ring-shaped member externally fitted to the valve shaft member so as to be movable in the axial direction, A main valve chamber and a sub-valve chamber in the housing member, which are partitioned by a partition; a first chamber at both ends, a third chamber, and a second chamber at an intermediate portion which are partitioned by a valve shaft member in the main valve chamber; A pressure fluid supply port formed in the housing member wall surface of the second chamber; a first communication port formed in the housing member wall surface of the first chamber; and a second communication port formed in the housing member wall surface of the third chamber. A discharge port formed on the wall surface of the housing member of the sub-valve chamber; and a passage communicating the main valve chamber and the sub-valve chamber formed on the valve shaft member, wherein an axial direction of the valve shaft member and the floating ring member is provided. By movement
2. A method according to claim 1, wherein one of the first and second communication ports is switched to a position communicating with the pressure fluid supply port and the other is connected to a position communicating with the discharge port.
Position 4-port directional control valve. 2. A housing member, a valve shaft member provided in the housing member, the valve shaft member being axially movable in a housing member, a floating ring-shaped member externally fitted to the valve shaft member so as to be movable in the axial direction, A valve chamber in the housing member, which is partitioned by a partition, and first ends of both ends of the valve chamber, which are partitioned by the valve shaft member.
A second chamber in the chamber, the third chamber, and the intermediate portion; a pressure fluid supply port formed in the housing member wall surface of the second chamber; a first flow port formed in the housing member wall surface of the first chamber; A second flow port formed in the wall surface of the housing member of the chamber; and a passage having a function as a discharge port communicating the outside of the housing with the valve chamber formed in the valve shaft member. By axial movement,
2. A method according to claim 1, wherein one of the first and second communication ports is switched to a position communicating with the pressure fluid supply port and the other is connected to a position communicating with the discharge port.
Position 4-port directional control valve.