WO2014147897A1

WO2014147897A1 - Rotary valve device

Info

Publication number: WO2014147897A1
Application number: PCT/JP2013/082704
Authority: WO
Inventors: 裕正高田
Original assignee: 株式会社鷺宮製作所
Priority date: 2013-03-22
Filing date: 2013-12-05
Publication date: 2014-09-25
Also published as: JP2014185662A; JP5907506B2; CN105190136A; CN105190136B

Abstract

Provided is a rotary valve device that can suppress the force for pressing a valve member against a valve seat surface. In a two-way valve (1), the cylindrical section (31) of a valve member (30) has a small-diameter cylindrical portion (31a), a large-diameter cylindrical portion (31b), and a cylindrical portion step surface (31c) formed between the outer peripheral surface (31a1) of the small-diameter cylindrical portion (31a) and the outer peripheral surface (31b1) of the large-diameter cylindrical portion (31b). Also, a valve main body (10) has a valve member support section (15) provided with: a small-diameter hole section (15a) to which the small-diameter cylindrical portion (31a) can rotatably fit; a large-diameter hole section (15b) to which the large-diameter cylindrical portion (31b) can rotatably fit; and a support section step surface (15c) formed between the inner peripheral surface (15a1) of the small-diameter hole section (15a) and the inner peripheral surface (15b1) of the large-diameter hole section (15b). Also, an annular seal ring (38) is provided in the seal space (R) encircled by the outer peripheral surface (31a1) of the small-diameter cylindrical portion, the cylindrical portion step surface (31c), the inner peripheral surface (15b1) of the valve large-diameter hole section, and the support section step surface (15c).

Description

Rotary valve device

The present invention relates to a rotary valve device that switches a communication relationship of a plurality of valve ports determined according to a stop position of a valve member by rotation of the valve member.

As a conventional rotary valve device, for example, a four-way switching valve disclosed in Patent Document 1 is integrated with a large-diameter cylindrical valve case 811 and an upper end side of the valve case 811 as shown in FIG. A small-diameter cylindrical motor case 812 connected and closed at the upper end, a flat valve seat 813 attached to the valve case 811 so as to seal the opening at the other end of the valve case 811, and a valve seat 813 The rotary valve body 814 arranged to overlap the valve seat surface 813a facing the inside of the valve case 811 and the space inside the valve case 811 are partitioned in the vertical direction in the figure, and the pressure balance chamber 808 and the valve chamber 809 are formed. A partition 807 to be formed, a planetary gear speed reducer 815 installed in a pressure balance chamber 808 in the valve case 811, and a stepping motor 820 are provided.

The valve seat 813 is provided with a first switching port C1 (not shown) and a second switching port C2, and a first fixed port E1 and a second fixed port E2 that are reversibly communicated with the switching ports C1 and C2. It has been. The valve body 814 is accommodated in the valve case 811, and its columnar portion 814 a is rotatably supported by a through hole 807 a provided in the center of the partition wall 807, and a flange portion 814 b integrally connected to the columnar portion 814 a is provided. It is arranged so as to overlap the valve seat surface 813a. The flange portion 814b is provided with an airtight communication hole 814c that always communicates with the second fixed port E2. The valve body 814 is connected to the output shaft 815a of the planetary gear speed reducer 815, and is rotated along with the rotation of the output shaft 815a.

Rotation of the stepping motor 820 is transmitted to the valve body 814 via the planetary gear speed reducer 815, and the valve body 814 is rotated so as to switch the stop position. As a result, when the valve body 814 is in one stop position, the second fixed port E2 and the second switching port C2 are communicated with each other through the airtight communication hole 814c, and the first fixed port E1 and the first fixed port E1 are connected to the first fixed port E1. The switching port C1 is exposed to the valve chamber 809, and these ports are communicated and connected. Further, when the valve body 814 is in another stop position, the second fixed port E2 and the first switching port C1 are connected to each other through the airtight communication hole 814c, and the first fixed port E1 and the second switching port are connected. The port C2 is exposed to the valve chamber 809, and these ports are communicated and connected. In this way, the communication relationship of each port is switched.

Such a four-way switching valve 801 is used by being incorporated in, for example, a refrigerant circulation circuit that circulates refrigerant between an indoor unit and an outdoor unit of an air conditioner. In this case, the second fixed port E2 of the four-way switching valve 801 is connected to the suction side of the compressor. Therefore, since the flow direction of the fluid flowing through the second fixed port E2 is constant and the fluid pressure is also relatively small, the refrigerant pressure (fluid pressure) in the airtight communication hole 814c and the pressure balance chamber 808 does not fluctuate greatly. It is almost constant.

On the other hand, such a rotary valve device is also used in, for example, a circuit in which the fluid flow direction changes. The configuration of a two-way valve, which is an example of a rotary valve device used in a circuit or the like in which the fluid flow direction changes, is shown in FIGS. 19 and 20.

19 includes a valve body 910 and a valve member 930 accommodated in the valve body 910. The valve member 930 includes a columnar portion 931 that is supported by the valve main body 910 so as to be rotatable about an axis, and a bowl-shaped valve body portion 933 that is integrally connected to the columnar portion 931. The valve member 930 is accommodated in the valve main body 910 to partition the space in the valve main body 910 into a valve chamber B and a back pressure chamber H. Further, a seal member 938 is provided between the cylindrical portion 931 and the valve main body 910, and the valve chamber B and the back pressure chamber H are sealed and separated from each other by the seal member 938. The valve member 930 is applied with a force to be pressed against the valve seat portion 920 provided integrally with the valve body 910 by the coil spring 963, and the lower end surface 933 a of the valve body portion 933 is the valve seat surface of the valve seat portion 920. It abuts on 922a. The lower end surface 933a of the valve body portion 933 is formed with a sealed recess 934 that extends to the valve body portion 933, and a sealed space G is formed between the sealed recess 934 and the valve seat surface 922a. Further, the valve member 930 is formed with a pressure equalizing hole 936 that communicates the sealed space G of the valve body portion 933 with the back pressure chamber H.

The valve seat portion 920 is formed with a first valve port P1 and a second valve port P2 that open to the valve seat surface 922a. Then, when the valve member 930 is rotated by the rotation drive unit 950 via the rotation shaft portion 940, at least one of the first valve port P1 and the second valve port P2 is opened and closed. Specifically, as shown in FIG. 20 (a), both the first valve port P1 and the second valve port P2 are exposed to the valve chamber B and fluid flow is allowed (valve open state). As shown in (b) and (c), one of the first valve port P1 and the second valve port P2 is covered with the valve body portion 933 of the valve member 930 (that is, exposed in the sealed space G). The fluid flow is restricted (valve closed state).

For example, when one of the first valve port P1 and the second valve port P2 is covered with the valve body portion 933 of the valve member 930 and the flow of the fluid is restricted, the flow direction of the fluid changes. Then, the fluid pressure in the valve chamber B and the fluid in the sealed space G and the back pressure chamber H (that is, one of the first valve port P1 and the second valve port P2 covered by the valve body portion 933). The relationship between the pressure and the pressure changes, and in some cases, a force that lifts the valve member 930 from the valve seat portion 920 by the fluid pressure acts.

Therefore, even if the relationship between the fluid pressure in the valve chamber B and the fluid pressure in the sealed space G and the back pressure chamber H changes, the coil spring 963 prevents the valve seat 920 from floating. A force for pressing the valve member 930 against the valve seat 920 is set.

JP 2001-141093 A

In the above-described two-way valve 901, the balance of force due to the fluid pressure applied to the valve member 930 changes due to various factors such as the shape tolerance of the valve member 930, for example. Therefore, even when the worst case is used, a force for pressing the valve member 930 by the coil spring 963 is set so that the valve member 930 does not float from the valve seat portion 920.

Hereinafter, specific examples of the setting of the coil spring 963 will be described with reference to FIGS.

For example, as shown in FIG. 21 (a), when the valve member 930 is pressed against the valve seat portion 920 by the coil spring 963, the outer peripheral edge 933a1 of the lower end surface 933a of the valve body portion 933 is changed to the valve seat due to the shape tolerance. It is conceivable that the inner peripheral edge 933a2 is separated from the valve seat surface 922a while being in contact with the surface 922a. In this case, the fluid pressure in the sealed space G is applied to the lower end surface 933a of the valve body portion 933. That is, as shown in FIG. 21B, the planar view area S1 of the portion where the fluid pressure in the sealed space G in the valve member 930 is applied is the area within the outer peripheral edge 933a1 of the lower end surface 933a of the valve body portion 933 ( (Hatched area). Hereinafter, this configuration is referred to as a “closed space maximum configuration”.

Further, as shown in FIG. 22A, when the valve member 930 is pressed against the valve seat portion 920 by the coil spring 963, the inner peripheral edge 933a2 of the lower end surface 933a of the valve body portion 933 becomes the valve seat due to the shape tolerance. It is conceivable that the outer peripheral edge 933a1 is in contact with the surface 922a and is separated from the valve seat surface 922a. In this case, the fluid pressure in the valve chamber B is applied to the lower end surface 933a of the valve body portion 933. That is, as shown in FIG. 22B, the planar view area S2 of the portion where the fluid pressure in the sealed space G in the valve member 930 is applied is the area within the inner peripheral edge 933a2 of the lower end surface 933a of the valve body portion 933 ( (Hatched area). Hereinafter, this configuration is referred to as a “closed space minimum configuration”.

And in each of these sealed space maximum configuration and sealed space minimum configuration, about the four cases when the fluid pressure in the sealed space G and the back pressure chamber H is higher and lower than the fluid pressure in the valve chamber B, An example of the force acting on the valve member 930 is shown below.

In the following description, the planar view area SH of the upper end surface 931a of the cylindrical portion 931 of the valve member 930 is 380 square millimeters (that is, the diameter D of the cylindrical portion 931 is 22 mm), and the planar view area S1 when the sealed space is the maximum configuration. (That is, the area in the outer peripheral edge 933a1 of the lower end surface 933a) is 385 square millimeters, and the planar view area S2 (that is, the area in the inner peripheral edge 933a2 of the lower end surface 933a) is 250 square millimeters, It is said.

Further, when the fluid pressure in the sealed space G and the back pressure chamber H is higher than the fluid pressure in the valve chamber B, the pressure difference ΔP1 between these fluid pressures is set to 3.0 MPa, and the inside of the sealed space G and the back pressure chamber H The pressure difference ΔP2 between these fluid pressures when the fluid pressure is lower than the fluid pressure in the valve chamber B is −3.0 MPa.

The force F1 acting on the valve member 930 due to the fluid pressure in the sealed space G is caused by the pressure difference between the fluid pressure in the sealed space G and the fluid pressure in the valve chamber B (the pressure difference ΔP1 or ΔP2). It is obtained by multiplying the planar view area (the planar view area S1 or S2) of the location where the fluid pressure in the sealed space G at 930 is applied. The force F2 acting on the valve member 930 by the fluid pressure in the back pressure chamber H is a pressure difference between the fluid pressure in the back pressure chamber H and the fluid pressure in the valve chamber B (the pressure difference ΔP1 or ΔP2). It is obtained by multiplying the planar view area (the planar view area SH) of the location where the fluid pressure in the back pressure chamber H in the valve member 930 is applied. Hereinafter, the direction in which the valve member 930 is pressed against the valve seat surface is positive.

(Case 1: When the fluid pressure in the sealed space G and the back pressure chamber H is higher than the fluid pressure in the valve chamber B in the maximum configuration of the sealed space)
In case 1 shown in FIG. 23, the force F1 acting on the valve member 930 by the fluid pressure in the sealed space G is:
F1 = (− ΔP1) × S1 = −1155 [N] (1-1)
The force F2 acting on the valve member 930 due to the fluid pressure in the back pressure chamber H is
F2 = ΔP1 × SH = 1140 [N] (1-2)
It becomes. Therefore, from the above formula, the valve member 930 has
F = F1 + F2 = −15 [N]
That is, a force of 15 [N] is working to lift the valve member 930 from the valve seat surface 922a. In this case, it is necessary to press the valve member 930 toward the valve seat surface 922a with a force exceeding at least 15 [N] by the coil spring 963.

(Case 2: When the fluid pressure in the sealed space G and the back pressure chamber H is higher than the fluid pressure in the valve chamber B in the minimum configuration of the sealed space)
In the case 2 shown in FIG. 24, the force F1 acting on the valve member 930 by the fluid pressure in the sealed space G is
F1 = (− ΔP1) × S2 = −750 [N] (1-3)
The force F2 acting on the valve member 930 due to the fluid pressure in the back pressure chamber H is
F2 = ΔP1 × SH = 1140 [N] (1-4)
It becomes. Therefore, from the above formula, the valve member 930 has
F = F1 + F2 = 390 [N]
In other words, a force of 390 [N] acts so as to press the valve member 930 against the valve seat surface 922a. In this case, even if the valve member 930 is not pressed against the valve seat surface 922a by the coil spring 963, the valve member 930 does not rise from the valve seat surface 922a.

(Case 3: When the fluid pressure in the sealed space G and the back pressure chamber H is lower than the fluid pressure in the valve chamber B in the maximum configuration of the sealed space)
In the case 3 shown in FIG. 25, the force F1 acting on the valve member 930 by the fluid pressure in the sealed space G is
F1 = (− ΔP2) × S1 = 1155 [N] (1-5)
The force F2 acting on the valve member 930 due to the fluid pressure in the back pressure chamber H is
F2 = ΔP2 × SH = −1140 [N] (1-6)
It becomes. Therefore, from the above formula, the valve member 930 has
F = F1 + F2 = 15 [N]
That is, a force of 15 [N] is acting so as to press the valve member 930 against the valve seat surface 922a. In this case, even if the valve member 930 is not pressed against the valve seat surface 922a by the coil spring 963, the valve member 930 does not rise from the valve seat surface 922a.

(Case 4: When the fluid pressure in the sealed space G and the back pressure chamber H is lower than the fluid pressure in the valve chamber B in the minimum configuration of the sealed space)
In the case 4 shown in FIG. 26, the force F1 acting on the valve member 930 by the fluid pressure in the sealed space G is:
F1 = (− ΔP2) × S2 = 750 [N] (1-7)
The force F2 acting on the valve member 930 due to the fluid pressure in the back pressure chamber H is
F2 = ΔP2 × SH = −1140 [N] (1-8)
It becomes. Therefore, from the above formula, the valve member 930 has
F = F1 + F2 = −390 [N]
That is, a force of 390 [N] is working so as to lift the valve member 930 from the valve seat surface 922a. In this case, it is necessary to press the valve member 930 toward the valve seat surface 922a with a force exceeding at least 390 [N] by the coil spring 963.

Among the cases 1 to 4 described above, in particular, in the case 4 where the fluid pressure in the back pressure chamber is lower than the fluid pressure in the valve chamber, the force with which the valve member 930 floats from the valve seat surface 922a becomes the largest. Therefore, in order to prevent the valve member 930 from floating from the valve seat surface 922a in any of the cases 1 to 4, the valve member 930 is not lifted from the valve seat surface 922a in the case 4 which is the worst case. What should I do? That is, the force FS that presses the valve member 930 toward the valve seat surface 922a by the coil spring 963 may be set so as to at least exceed 390 [N], which is the force that lifts the valve member 930 in the case 4.

However, in the two-way valve 901, when the force FS for pressing the valve member 930 by the coil spring 963 toward the valve seat surface 922 a is set to, for example, 391 [N] assuming the case 4, the case 2 In this state, a force F (= 390 [N]) pressed against the valve seat surface 922a by the fluid pressure against the valve member 930 and a force FS (= 391 [N] pressed against the valve seat surface 922a by the coil spring 963). N]) together, the valve member 930 is pressed against the valve seat surface 922a with a strong force. Therefore, since a large force is required to rotationally drive the valve member 930 pressed with such a strong force, there has been a problem that the rotational drive unit 950 must be enlarged.

Therefore, an object of the present invention is to provide a rotary valve device that can suppress the force pressing the valve member against the valve seat surface.

In order to solve the above-mentioned problems, the invention described in claim 1 is a valve main body having a space inside, a planar valve seat surface facing the space, and two openings opening in the valve seat surface. A valve seat having a valve port; a valve member that is arranged in the space so as to be slidably rotatable on the valve seat surface, and that switches a communication relationship between the two valve ports determined according to a stop position by rotation; And a pressing member that presses the valve member toward the valve seat surface, wherein the valve member is supported by the valve body so as to be rotatable about an axis, and the shaft And a valve body portion that opens and closes at least one of the two valve ports according to the stop position, and the valve body is formed by the valve member. By being partitioned, it is formed on one end side of the shaft portion. A valve chamber in which the valve body portion is accommodated, and a back pressure chamber formed on the other end side of the shaft portion, and the valve main body or the valve member is connected to the two valve ports. The valve member has a pressure equalizing path that connects the valve port that is opened and closed by the valve body portion and the back pressure chamber, and the fluid pressure in the back pressure chamber is lower than the fluid pressure in the valve chamber. The planar view area to which the fluid pressure of the back pressure chamber is applied is configured to be smaller than the planar view area when the fluid pressure of the back pressure chamber is higher than the fluid pressure of the valve chamber. This is a rotary valve device.

In order to solve the above-mentioned problem, the invention described in claim 2 is a valve body having a space inside, a planar valve seat surface facing the space, and a plurality of openings that open to the valve seat surface. A valve member having a valve port, a valve member that is arranged in the space so as to be slidably rotatable on the valve seat surface, and switches a communication relationship of the plurality of valve ports determined according to a stop position by rotation; And a pressing member that presses the valve member toward the valve seat surface, wherein the valve member is supported by the valve body so as to be rotatable about an axis, and the shaft One or a plurality of sealed communication passages provided at one end of the portion, forming a sealed space with the valve seat surface, and communicating the plurality of valve ports in a predetermined combination according to the stop position through the sealed space And a valve body portion provided with A body is formed on one end side of the shaft portion by partitioning the space by the valve member, and is formed on the other end side of the shaft portion. A back pressure chamber, and the valve body or the valve member has a pressure equalizing path connecting any one of the sealed communication passages to the back pressure chamber, and a fluid in the back pressure chamber The planar view area to which the fluid pressure of the back pressure chamber in the valve member when the pressure is lower than the fluid pressure of the valve chamber is higher than the fluid pressure of the valve chamber is higher than the fluid pressure of the valve chamber. The rotary valve device is configured to be smaller than a planar view area.

The invention described in claim 3 is the invention described in

claim

1 or 2, wherein an annular seal member is provided between the valve main body and the valve member to seal between them. The seal member is pressed against the valve member when the fluid pressure in the back pressure chamber is higher than the fluid pressure in the valve chamber, and the seal member is pressed when the fluid pressure in the back pressure chamber is lower than the fluid pressure in the valve chamber. The valve body is configured to be pressed against the valve body.

The invention described in claim 4 is the invention described in claim 3, wherein the shaft portion of the valve member has a small-diameter shaft portion arranged so that one end surface thereof faces the back pressure chamber, A large-diameter shaft portion concentrically connected to the other end surface of the small-diameter shaft portion, and an outer peripheral surface of the small-diameter shaft portion and a shaft stepped surface formed between the outer peripheral surface of the large-diameter shaft portion, A main body includes a small diameter hole portion in which the small diameter shaft portion is rotatably fitted, a large diameter hole portion in which the large diameter shaft portion is rotatably fitted, and an inner peripheral surface and a large diameter of the small diameter hole portion. A support member step surface formed between the inner peripheral surface of the hole portion, and a valve member support portion provided with the seal member, the outer peripheral surface of the small-diameter shaft portion, the shaft step surface, In the space surrounded by the inner peripheral surface of the large-diameter hole and the stepped surface of the support portion, the space between the outer peripheral surface of the small-diameter shaft portion and the inner peripheral surface of the large-diameter hole is tight. It is provided so as to is characterized in.

In order to solve the above-mentioned problem, the invention described in claim 5 is a valve main body provided with a space inside, a planar valve seat surface facing the space, and two open to the valve seat surface. A valve seat having a valve port; a valve member that is arranged in the space so as to be slidably rotatable on the valve seat surface, and that switches a communication relationship between the two valve ports determined according to a stop position by rotation; A rotary valve device comprising: a pressing member that presses the valve member toward the valve seat surface; and a cylindrical portion that is rotatably supported by the valve main body around an axis thereof, and the column And a valve body portion that opens and closes at least one of the two valve ports according to the stop position, and the valve body defines the space by the valve member. The one end side of the cylindrical part A valve chamber in which the valve body portion is accommodated and a back pressure chamber formed on the other end side of the cylindrical portion, and the valve body or the valve member is the two valve ports. The pressure port connecting the valve port that is opened and closed by the valve body portion and the back pressure chamber, and the cylindrical portion is arranged so that one end surface faces the back pressure chamber. A cylindrical portion, a large-diameter cylindrical portion that is coaxially connected to the other end surface of the small-diameter cylindrical portion, and a cylindrical stepped surface formed between the outer peripheral surface of the small-diameter cylindrical portion and the outer peripheral surface of the large-diameter cylindrical portion. The valve main body includes a small diameter hole portion in which the small diameter cylindrical portion is rotatably fitted, a large diameter hole portion in which the large diameter cylindrical portion is rotatably fitted, and an inner portion of the small diameter hole portion. A support member step surface formed between the peripheral surface and the inner peripheral surface of the large-diameter hole portion, and the small-diameter column The outer peripheral surface of the small-diameter cylindrical portion and the inner periphery of the large-diameter hole portion in the space surrounded by the outer peripheral surface of the minute portion, the stepped surface of the cylindrical portion, the inner peripheral surface of the large-diameter hole portion, and the stepped surface of the support portion The rotary valve device is provided with an annular seal member that seals between the surfaces.

In order to solve the above-mentioned problem, a sixth aspect of the present invention provides a valve main body having a space inside, a planar valve seat surface facing the space, and a plurality of openings that open to the valve seat surface. A valve member having a valve port, a valve member that is arranged in the space so as to be slidably rotatable on the valve seat surface, and switches a communication relationship of the plurality of valve ports determined according to a stop position by rotation; A rotary valve device comprising: a pressing member that presses the valve member toward the valve seat surface; and a cylindrical portion that is rotatably supported by the valve main body around an axis thereof, and the column One or a plurality of sealed communication passages that are connected to one end of the portion, form a sealed space with the valve seat surface, and communicate the plurality of valve ports in a predetermined combination according to the stop position through the sealed space. A valve body portion provided, and The main body is formed on one end side of the columnar portion, the valve chamber accommodating the valve body portion, and on the other end side of the columnar portion by dividing the space by the valve member. A back pressure chamber, and the valve body or the valve member has a pressure equalizing path connecting any one of the sealed communication passages and the back pressure chamber, and the column portion is A small-diameter cylindrical portion disposed so that one end surface faces the back pressure chamber, a large-diameter cylindrical portion that is coaxially connected to the other end surface of the small-diameter cylindrical portion, an outer peripheral surface of the small-diameter cylindrical portion, and the large-diameter cylindrical portion A cylindrical stepped surface formed between outer peripheral surfaces, and the valve body is fitted with a small-diameter hole portion in which the small-diameter cylindrical portion is rotatably fitted, and the large-diameter cylindrical portion is rotatably fitted. A support step formed between the large-diameter hole portion to be joined and the inner peripheral surface of the small-diameter hole portion and the inner peripheral surface of the large-diameter hole portion And a valve member supporting portion provided with a surface, and an outer peripheral surface of the small diameter cylindrical portion, a stepped surface of the cylindrical portion, an inner peripheral surface of the large diameter hole portion, and a space surrounded by the stepped surface of the supporting portion The rotary valve device is characterized in that an annular seal member is provided for sealing between the outer peripheral surface of the small-diameter cylindrical portion and the inner peripheral surface of the large-diameter hole portion.

According to the first and second aspects of the present invention, when the fluid pressure in the back pressure chamber is lower than the fluid pressure in the valve chamber, the plan view area to which the fluid pressure in the back pressure chamber in the valve member is applied is the back pressure chamber. The fluid pressure is smaller than the planar view area when the fluid pressure is higher than the fluid pressure in the valve chamber. Thus, when the fluid pressure in the back pressure chamber is lower than the fluid pressure in the valve chamber, the force that lifts the valve member from the valve seat surface is exerted by the fluid pressure in the back pressure chamber. Since the area of the portion where the fluid pressure in the back pressure chamber in the member is applied (that is, the area in plan view) is reduced, the force to lift the valve member from the valve seat surface can be reduced. Thereby, since the force which presses the valve member by a pressing member toward a valve seat surface can be made small, the force which presses a valve member against a valve seat surface can be suppressed.

According to the invention described in claim 3, between the valve main body and the valve member, an annular seal member for sealing between them is provided. The seal member is pressed against the valve member when the fluid pressure in the back pressure chamber is higher than the fluid pressure in the valve chamber, and the seal member is pressed against the valve body when the fluid pressure in the back pressure chamber is lower than the fluid pressure in the valve chamber. It is configured to be. As a result, the annular seal member that seals between the valve body and the valve member is subjected to the fluid pressure of the back pressure chamber on a part of the surface and the fluid of the valve chamber on the other part of the surface. Pressure is applied. When the seal member is pressed against the valve member when the fluid pressure in the back pressure chamber is higher than the fluid pressure in the valve chamber, the fluid pressure in the back pressure chamber added to the planar view area of a part of the surface of the seal member is It is also added to the valve member. Further, when the seal member is pressed against the valve body when the fluid pressure in the back pressure chamber is lower than the fluid pressure in the valve chamber, the fluid pressure in the valve chamber applied to the other part of the surface of the seal member is applied to the valve body. Is also added. That is, when the fluid pressure in the back pressure chamber is lower than the fluid pressure in the valve chamber, the planar view area to which the fluid pressure of the back pressure chamber in the valve member is applied (that is, the planar view area applied directly or indirectly through the seal member) ) Is configured to be smaller than the planar view area when the fluid pressure in the back pressure chamber is higher than the fluid pressure in the valve chamber. Therefore, when the fluid pressure in the back pressure chamber is lower than the fluid pressure in the valve chamber, the force that lifts the valve member from the valve seat surface is exerted by the fluid pressure in the back pressure chamber. Since the area where the fluid pressure is applied in the pressure chamber (that is, the area in plan view) is reduced, the force for lifting the valve member from the valve seat surface can be reduced. Thereby, since the force which presses the valve member by a pressing member toward a valve seat surface can be made small, the force which presses a valve member against a valve seat surface can be suppressed.

According to the invention described in claim 4, the shaft portion of the valve member includes a small-diameter shaft portion disposed so that one end surface thereof faces the back pressure chamber, and a large shaft continuously connected to the other end surface of the small-diameter shaft portion. And a shaft stepped surface formed between the outer peripheral surface of the small-diameter shaft portion and the outer peripheral surface of the large-diameter shaft portion. The valve body has a small diameter hole portion in which the small diameter shaft portion is rotatably fitted, a large diameter hole portion in which the large diameter shaft portion is rotatably fitted, and an inner peripheral surface and a large diameter hole portion of the small diameter hole portion. And a support member step surface formed between the inner peripheral surface and the valve member support portion. Then, the outer circumferential surface of the small-diameter shaft portion and the large-diameter hole portion are sealed in a space surrounded by the outer peripheral surface of the small-diameter shaft portion, the shaft step surface, the inner peripheral surface of the large-diameter hole portion, and the step surface of the support portion. It is provided so as to seal between the inner peripheral surface of the. Thus, the annular seal member that seals between the outer peripheral surface of the small-diameter shaft portion of the valve member and the inner peripheral surface of the large-diameter hole portion of the valve body has a back pressure chamber on a part of its surface. Fluid pressure is applied, and the fluid pressure of the valve chamber is applied to the other part of the surface. Then, when the fluid pressure in the back pressure chamber is higher than the fluid pressure in the valve chamber, the seal member is pressed against the shaft step surface of the valve member, and is added to the planar view area of a part of the surface of the seal member. Is also applied to the valve member. Further, when the fluid pressure in the back pressure chamber is lower than the fluid pressure in the valve chamber, the seal member is pressed against the stepped surface of the support portion of the valve body, and the fluid pressure in the valve chamber is applied to the other part of the surface of the seal member. Is also added to the valve body. That is, when the fluid pressure in the back pressure chamber is lower than the fluid pressure in the valve chamber, the planar view area to which the fluid pressure of the back pressure chamber in the valve member is applied (that is, the planar view area applied directly or indirectly through the seal member) ) Is configured to be smaller than the planar view area when the fluid pressure in the back pressure chamber is higher than the fluid pressure in the valve chamber. That is, when the fluid pressure in the back pressure chamber is higher than the fluid pressure in the valve chamber, the seal member is pressed against the stepped surface of the shaft by the fluid pressure in the back pressure chamber, and the outer diameter of the large-diameter shaft portion in plan view in the valve member. The fluid pressure in the back pressure chamber is applied to a further inner portion. In addition, when the fluid pressure in the back pressure chamber is lower than the fluid pressure in the valve chamber, the seal member is pressed against the stepped surface of the shaft portion by the fluid pressure in the valve chamber, and the valve member is inside the outer diameter of the small-diameter shaft portion in plan view. The fluid pressure in the back pressure chamber is applied to Therefore, when the fluid pressure in the back pressure chamber is lower than the fluid pressure in the valve chamber, the force that lifts the valve member from the valve seat surface is exerted by the fluid pressure in the back pressure chamber. Since the area where the fluid pressure is applied in the pressure chamber (that is, the area in plan view) is reduced, the force for lifting the valve member from the valve seat surface can be reduced. Thereby, since the force which presses the valve member by a pressing member toward a valve seat surface can be made small, the force which presses a valve member against a valve seat surface can be suppressed.

According to the invention described in claims 5 and 6, the cylindrical portion that is rotatably supported around the shaft center by the valve main body is a small-diameter cylindrical portion that is arranged so that one end surface faces the back pressure chamber, A large-diameter cylindrical portion that is coaxially connected to the other end surface of the small-diameter cylindrical portion, and a columnar step surface formed between the outer peripheral surface of the small-diameter cylindrical portion and the outer peripheral surface of the large-diameter cylindrical portion. Further, the valve main body includes a small diameter hole portion in which the small diameter cylindrical portion of the column portion is rotatably fitted, a large diameter hole portion in which the large diameter cylindrical portion of the column portion is rotatably fitted, and a small diameter hole portion. And a support member step surface formed between the inner peripheral surface and the inner peripheral surface of the large-diameter hole portion. Then, in the space surrounded by the outer peripheral surface of the small-diameter cylindrical portion of the cylindrical portion, the stepped surface of the cylindrical portion, the inner peripheral surface of the large-diameter hole portion of the valve member supporting portion of the valve body, and the stepped surface of the supporting portion, An annular seal member is provided that seals between the outer peripheral surface and the inner peripheral surface of the large-diameter hole. As a result, the fluid pressure in the valve chamber is applied to the position on the cylindrical stepped surface side of the seal member, and the fluid pressure in the back pressure chamber is applied to the support member stepped surface side of the seal member. Yes. Therefore, when the fluid pressure in the back pressure chamber is higher than the fluid pressure in the valve chamber, the seal member is pressed against the stepped surface of the cylinder portion by the fluid pressure in the back pressure chamber, and the outer diameter of the large-diameter cylinder portion in plan view in the valve member The fluid pressure in the back pressure chamber is applied to a further inner portion. Further, when the fluid pressure in the back pressure chamber is lower than the fluid pressure in the valve chamber, the seal member is pressed against the stepped surface of the cylindrical portion by the fluid pressure in the valve chamber, and the valve member is inside the outer diameter of the small-diameter cylindrical portion in plan view. The fluid pressure in the back pressure chamber is applied to That is, when the fluid pressure in the back pressure chamber is lower than the fluid pressure in the valve chamber, the force that lifts the valve member from the valve seat surface is exerted by the fluid pressure in the back pressure chamber. Since the area of the portion to which the fluid pressure is applied is reduced, the force for lifting the valve member from the valve seat surface can be reduced. Thereby, since the force which presses the valve member by a pressing member toward a valve seat surface can be made small, the force which presses a valve member against a valve seat surface can be suppressed.

It is a longitudinal cross-sectional view of the two-way valve which is the 1st Embodiment of this invention. It is the expanded sectional view which expanded a part of two-way valve of FIG. FIG. 2 is a cross-sectional view taken along line XX in FIG. 1, (a) shows a state where the valve member is in a first stop position (valve open state), and (b) shows a state where the valve member is in a second stop position. A state (valve closed state in which the first valve port is closed) is shown, and (c) shows a state in which the valve member is in the third stop position (valve closed state in which the second valve port is closed). It is a figure explaining the location which receives the fluid pressure in the sealed space of the valve body part in a valve member, Comprising: (a) is sectional drawing of the valve member in case the sealed space of a valve body part becomes the maximum, ( (b) is the top view which looked at the valve seat surface from the direction of the axis | shaft L in the structure (maximum structure in sealed space) provided with the valve member of (a). It is a figure explaining the location which receives the fluid pressure in the sealed space of the valve body part in a valve member, Comprising: (a) is sectional drawing of the valve member in case the sealed space of a valve body part becomes the minimum, ( (b) is the top view which looked at the valve-seat surface from the direction of the axis | shaft L in the structure (minimum structure in sealed space) provided with the valve member of (a). It is a figure explaining operation | movement of the two-way valve of FIG. 1, Comprising: (a) is a longitudinal cross-sectional view of a two-way valve, (b) looked at the valve-seat surface of (a) from the axis | shaft L direction. (C) is an enlarged cross-sectional view of a part of (a). (Case 1: In the maximum configuration of the sealed space, the fluid pressure in the sealed space and the back pressure chamber is the fluid pressure in the valve chamber. If higher). It is a figure explaining operation | movement of the two-way valve of FIG. 1, Comprising: (a) is a longitudinal cross-sectional view of a two-way valve, (b) looked at the valve-seat surface of (a) from the axis | shaft L direction. (C) is an enlarged cross-sectional view in which part of (a) is enlarged (case 2: in the minimum configuration of the sealed space, the fluid pressure in the sealed space and the back pressure chamber is the fluid pressure in the valve chamber). If higher). It is a figure explaining operation | movement of the two-way valve of FIG. 1, Comprising: (a) is a longitudinal cross-sectional view of a two-way valve, (b) looked at the valve-seat surface of (a) from the axis | shaft L direction. (C) is an enlarged cross-sectional view in which a part of (a) is enlarged (case 3: in the maximum configuration of the sealed space, the fluid pressure in the sealed space and the back pressure chamber is the fluid pressure in the valve chamber). If lower). It is a figure explaining operation | movement of the two-way valve of FIG. 1, Comprising: (a) is a longitudinal cross-sectional view of a two-way valve, (b) looked at the valve-seat surface of (a) from the axis | shaft L direction. (C) is an enlarged cross-sectional view in which a part of (a) is enlarged (case 4: in the minimum configuration of the sealed space, the fluid pressure in the sealed space and the back pressure chamber is the fluid pressure in the valve chamber). If lower). It is a longitudinal cross-sectional view of the flow-path switching valve which is the 2nd Embodiment of this invention. FIG. 11 is a cross-sectional view taken along line XX in FIG. 10, where (a) shows a state where the valve member is in the first stop position, and (b) shows a state where the valve member is in the second stop position. It is a figure explaining the location which receives the fluid pressure in the sealed space of the valve body part in a valve member, Comprising: (a) is sectional drawing of the valve member in case the sealed space of a valve body part becomes the maximum, ( (b) is the top view which looked at the valve seat surface from the direction of the axis | shaft L in the structure (maximum structure in sealed space) provided with the valve member of (a). It is a figure explaining the location which receives the fluid pressure in the sealed space of the valve body part in a valve member, Comprising: (a) is sectional drawing of the valve member in case the sealed space of a valve body part becomes the minimum, ( (b) is the top view which looked at the valve-seat surface from the direction of the axis | shaft L in the structure (minimum structure in sealed space) provided with the valve member of (a). It is a figure explaining operation | movement of the flow-path switching valve of FIG. 10, Comprising: (a) is a longitudinal cross-sectional view of a flow-path switching valve, (b) is a valve seat surface of (a) from the axis | shaft L direction. (C) is an enlarged cross-sectional view of a part of (a) (case 1: in the maximum configuration of the sealed space, the fluid pressure in the sealed space and the back pressure chamber is increased in the valve chamber). If higher than fluid pressure). It is a figure explaining operation | movement of the flow-path switching valve of FIG. 10, Comprising: (a) is a longitudinal cross-sectional view of a flow-path switching valve, (b) is a valve seat surface of (a) from the axis | shaft L direction. (C) is an enlarged cross-sectional view enlarging a part of (a) (Case 2: In the minimum configuration of the sealed space, the fluid pressure in the sealed space and the back pressure chamber is changed in the valve chamber. If higher than fluid pressure). It is a figure explaining operation | movement of the flow-path switching valve of FIG. 10, Comprising: (a) is a longitudinal cross-sectional view of a flow-path switching valve, (b) is a valve seat surface of (a) from the axis | shaft L direction. (C) is an enlarged cross-sectional view enlarging a part of (a) (Case 3: In the maximum configuration of the sealed space, the fluid pressure in the sealed space and the back pressure chamber is If lower than fluid pressure). It is a figure explaining operation | movement of the flow-path switching valve of FIG. 10, Comprising: (a) is a longitudinal cross-sectional view of a flow-path switching valve, (b) is a valve seat surface of (a) from the axis | shaft L direction. (C) is an enlarged cross-sectional view enlarging a part of (a) (Case 4: In the minimum configuration of the sealed space, the fluid pressure in the sealed space and the back pressure chamber is changed in the valve chamber. If lower than fluid pressure). It is a longitudinal cross-sectional view of a four-way switching valve as an example of a conventional rotary valve device. It is a longitudinal cross-sectional view of the two-way valve of another example of the conventional rotary valve device. FIG. 20 is a cross-sectional view taken along the line XX of FIG. 19, where (a) shows a state where the valve member is in the first stop position (valve open state), and (b) shows that the valve member is in the second stop position. A state (valve closed state in which the first valve port is closed) is shown, and (c) shows a state in which the valve member is in the third stop position (valve closed state in which the second valve port is closed). It is a figure explaining the location which receives the fluid pressure in the sealed space of the valve body part in the valve member of the two-way valve of FIG. 19, Comprising: (a) is a valve member in case the sealed space of a valve body part becomes the largest (B) is the top view which looked at the valve-seat surface from the direction of the axis | shaft L in the structure (maximum structure in sealed space) provided with the valve member of (a). It is a figure explaining the location which receives the fluid pressure in the sealed space of the valve body part in the valve member of the two-way valve of FIG. 19, Comprising: (a) The valve member in case the sealed space of a valve body part becomes the minimum (B) is the top view which looked at the valve-seat surface from the direction of the axis | shaft L in the structure (minimum structure in sealed space) provided with the valve member of (a). It is a figure explaining operation | movement of the two-way valve of FIG. 19, Comprising: (a) is a longitudinal cross-sectional view of a two-way valve, (b) saw the valve seat surface of (a) from the axis | shaft L direction. FIG. 6 is a plan view (case 1: when the fluid pressure in the sealed space and the back pressure chamber is higher than the fluid pressure in the valve chamber in the maximum configuration of the sealed space). It is a figure explaining operation | movement of the two-way valve of FIG. 19, Comprising: (a) is a longitudinal cross-sectional view of a two-way valve, (b) saw the valve seat surface of (a) from the axis | shaft L direction. FIG. 5 is a plan view (case 2: in the minimum configuration of the sealed space, when the fluid pressure in the sealed space and the back pressure chamber is higher than the fluid pressure in the valve chamber). It is a figure explaining operation | movement of the two-way valve of FIG. 19, Comprising: (a) is a longitudinal cross-sectional view of a two-way valve, (b) saw the valve seat surface of (a) from the axis | shaft L direction. FIG. 6 is a plan view (case 3: when the fluid pressure in the sealed space and the back pressure chamber is lower than the fluid pressure in the valve chamber in the maximum configuration of the sealed space). It is a figure explaining operation | movement of the two-way valve of FIG. 19, Comprising: (a) is a longitudinal cross-sectional view of a two-way valve, (b) saw the valve seat surface of (a) from the axis | shaft L direction. FIG. 6 is a plan view (case 4: when the fluid pressure in the sealed space and the back pressure chamber is lower than the fluid pressure in the valve chamber in the minimum configuration of the sealed space).

(First embodiment)
Hereinafter, the configuration of the two-way valve as the first embodiment of the rotary valve device of the present invention will be described with reference to FIGS. 1 to 3, and the operation will be described with reference to FIGS. .

FIG. 1 is a longitudinal sectional view of a two-way valve according to a first embodiment of the present invention. FIG. 2 is an enlarged cross-sectional view in which a part of the two-way valve of FIG. 1 is enlarged. 3 is a cross-sectional view taken along the line XX in FIG. 1. FIG. 3A shows a state in which the valve member is in the first stop position (valve open state), and FIG. 2 shows a state at the stop position (closed state with the first valve port closed), and (c) shows a state at which the valve member is in the third stop position (closed state with the second valve closed). Show. In addition, the concept of “upper and lower” in the following description corresponds to the upper and lower sides in FIG. 1 and indicates the relative positional relationship between the members, and does not indicate the absolute positional relationship.

The two-way valve of the first embodiment (indicated by reference numeral 1 in each figure) is disposed in a circuit in which the flow direction of fluid changes, for example, and is used to allow or restrict the flow of fluid. It is a way valve.

As shown in FIGS. 1 to 3, the two-way valve 1 of the present embodiment includes a valve body 10, a valve seat portion 20, a valve member 30, a seal ring 38, a rotating shaft portion 40, and a rotation driving portion. 50 and a coil spring 63.

The valve body 10 is made of, for example, stainless steel, aluminum alloy, or the like, and is formed on the first portion 11 so as to close the substantially cylindrical first portion 11 and the upper end of the first portion 11 in the drawing. And a substantially disc-shaped second portion 12 fixedly attached.

In the center of the second portion 12, a circular through hole 13 having a circular shape in plan view is formed. The circular through hole 13 is provided so that its axis L is orthogonal to a valve seat surface 22a of the valve seat portion 20 described later.

A bearing portion 16 that rotatably supports a rotating shaft portion 40, which will be described later, is inserted into the bearing insertion portion 14 in the upper portion of the circular through hole 13 in the figure, and the bearing portion 16 is fixed to the second portion 12 and provided. It has been.

In addition, a small-diameter hole portion 15a in which a small-diameter cylindrical portion 31a in a cylindrical portion 31 of a valve member 30 to be described later is rotatably fitted to the valve member support portion 15 in the lower portion of the circular through-hole 13 in the figure, and the cylindrical portion. A large-diameter hole portion 15b having a larger diameter than the small-diameter hole portion 15a, in which the large-diameter column portion 31b in 31 is rotatably fitted, is provided side by side in the axis L direction. Further, between the inner peripheral surface 15a1 of the small-diameter hole portion 15a and the inner peripheral surface 15b1 of the large-diameter hole portion 15b, a support portion step that is orthogonal (including substantially orthogonal) to the inner peripheral surface 15a1 and the inner peripheral surface 15b1. A surface 15c is provided.

A space Q is formed inside the valve body 10 by the space in the valve member support 15 of the circular space 13a of the second portion 12 communicating with the inner space 11a of the first portion 11. The space between the first portion 11 and the second portion 12 is sealed with a seal ring 66, and the space between the bearing portion 16 and the second portion 12 is sealed with a seal ring 67.

The valve seat portion 20 includes a valve seat main body 21 provided integrally with the first portion 11 so as to close the other lower end portion of the first portion 11 of the valve main body 10 in the figure, and the valve seat portion main body 21. And a thin plate member 22 fixedly stacked on a plane facing the space Q side in the valve body 10.

Further, the valve seat portion 20 is provided with a first valve port P1 and a second valve port P2 as two valve ports provided through the valve seat portion main body 21 and the thin plate member 22. In the present embodiment, the first valve port P1 and the second valve port P2 are arranged on a circumference centered on the axis L in a plan view from a direction orthogonal to the valve seat surface 22a.

The thin plate member 22 of the valve seat portion 20 is made of, for example, stainless steel, and includes a flat valve seat surface 22a facing the space Q in the valve body 10. The valve seat surface 22a is disposed to face the second portion 12 of the valve body 10 with a space therebetween.

The valve member 30 integrally includes a cylindrical portion 31 and a valve body portion 33 provided at the lower end of the cylindrical portion 31 in the drawing (that is, one end of the cylindrical portion 31). The valve member 30 is accommodated in the space Q in the valve body 10.

The cylindrical portion 31 integrally includes a small-diameter cylindrical portion 31a and a large-diameter cylindrical portion 31b having a larger diameter than the small-diameter cylindrical portion 31a connected coaxially to the small-diameter cylindrical portion 31a. Further, between the outer peripheral surface 31a1 of the small-diameter cylindrical portion 31a and the outer peripheral surface 31b1 of the large-diameter cylindrical portion 31b, a cylindrical step surface 31c that is orthogonal to (including substantially orthogonal to) the outer peripheral surface 31a1 and the outer peripheral surface 31b1 is provided. It has been. The small-diameter cylindrical portion 31a is formed so that the outer diameter is slightly smaller than the inner diameter of the small-diameter hole portion 15a of the valve member support portion 15 of the valve body 10 described above. The large-diameter cylindrical portion 31b is formed so that its outer shape is slightly smaller than the inner diameter of the large-diameter hole portion 15b of the valve member support portion 15 of the valve body 10 described above. The column portion 31 is fitted to the valve member support portion 15 so that its axis overlaps the axis L of the circular through hole 13. Thereby, the column part 31 (namely, valve member 30) is supported by the said valve member support part 15 so that rotation around an axial center is possible. The cylindrical portion 31 corresponds to an example of a shaft portion. Further, the small diameter cylindrical portion 31a, the large diameter cylindrical portion 31b, and the cylindrical portion step surface 31c correspond to an example of a small diameter shaft portion, a large diameter shaft portion, and a shaft portion step surface, respectively.

The outer peripheral surface 31a1 of the small-diameter cylindrical portion 31a of the cylindrical portion 31, the cylindrical stepped surface 31c of the cylindrical portion 31, the inner peripheral surface 15b1 of the large-diameter hole portion 15b of the valve member support portion 15, and the support portion of the valve member support portion 15. A seal ring 38 is disposed in the seal space R surrounded by the step surface 15c.

The seal ring 38 is made of, for example, a relatively soft elastic material such as nitrile rubber or silicone rubber. The seal ring 38 is formed in an annular shape (ring shape) in a state where no force is applied from the outside (a state where it is not elastically deformed). The inner diameter of the seal ring 38 is smaller than the outer diameter of the small-diameter cylindrical portion 31 a of the cylindrical portion 31, and the outer diameter of the seal ring 38 is larger than the inner diameter of the large-diameter hole portion 15 b of the valve member support portion 15. . As a result, when the seal ring 38 is accommodated in the seal space R, the seal ring 38 is crushed in the radial direction, and the inside of the outer peripheral surface 31a1 of the small-diameter cylindrical portion 31a of the cylindrical portion 31 and the large-diameter hole portion 15b of the valve member support portion 15. The space between the peripheral surface 15b1 is rotatably sealed. The fluid pressure in the valve chamber B is applied to a portion of the seal ring 38 on the columnar step surface 31c side (that is, another part of the surface of the seal member). The fluid pressure in the back pressure chamber H is applied to a portion (that is, a part of the surface of the seal member). The seal ring 38 corresponds to an example of a seal member.

The length of the cylindrical portion 31 is the same as or slightly shorter than the length of the valve member support portion 15 of the circular through-hole 13, and the entire small diameter cylindrical portion 31a and a portion of the large diameter cylindrical portion 31b are It is arranged in the valve member support part 15. Thereby, a sealed space (hereinafter referred to as “back pressure chamber H”) is formed on the upper end surface 31d (that is, one end surface of the small diameter cylindrical portion 31a) on the upper side of the cylindrical portion 31 in the drawing. That is, the valve member 30 is disposed on the upper end surface 31d side so as to form a back pressure chamber H that is partitioned so as to seal a part of the space Q between the valve member 30 and the second portion 12 of the valve body 10. ing. Further, the valve member 30 is disposed in the space Q, whereby the inner space 11a of the first portion 11 of the valve body 10 which is another part of the space Q is used as the valve chamber B and the back pressure chamber H. And partition. In the inner space 11a of the first portion 11, a valve body portion 33 described later is accommodated. In other words, when the valve body 10 is partitioned by the valve member 30, the valve chamber B in which the valve body portion 33 formed on one end side of the columnar portion 31 is accommodated and the other end of the columnar portion 31. And a back pressure chamber H formed on the side.

Further, the cylindrical portion 31 is provided with a rotation shaft portion attachment hole 32 to which one end portion 41 of the rotation shaft portion 40 described later is attached, opened in the upper end surface 31d. The rotation shaft portion mounting hole 32 is formed by connecting a small diameter portion 32a and a large diameter portion 32b having a diameter larger than the small diameter portion in the vertical direction. The diameter of the small diameter portion 32 a is slightly larger than the outer diameter of the one end portion 41 of the rotating shaft portion 40. The diameter of the large diameter portion 32 b is slightly larger than the outer diameter of the coil spring 63.

The valve body portion 33 has a bowl shape projecting in the radial direction of the cylindrical portion 31 and is formed in a substantially fan shape in a plan view viewed from the axis L direction. In the present embodiment, the valve body portion 33 is provided integrally with one end of the column portion 31. Of course, in addition to such a configuration, the valve body portion 33 may be formed separately from the cylindrical portion 31 and provided continuously to one end of the cylindrical portion 31 via a connecting member or the like. The valve body portion 33 is disposed in the valve chamber B (inner space 11 a) of the valve body 10. The lower end surface 33a of the valve body portion 33 is formed in a flat shape, and is densely stacked on the valve seat surface 22a of the valve seat portion 20 so as to be slidable and rotatable. The lower end surface 33 a of the valve body portion 33 is provided with a sealed recess 34 that extends inside the valve body portion 33.

The sealed recess 34 is formed in a shape in which the inside of the valve body portion 33 is cut out along its outer shape, and is formed in a substantially fan shape in a plan view viewed from the axis L direction. The sealed recess 34 is overlapped with the valve seat surface 22a to form a sealed space G with the valve seat surface 22a. The first valve port P1 or the second valve port P2 is covered by the valve body 33 and exposed in the sealed space G, so that the first valve port P1 or the second valve port P2 is separated from each other, The flow of fluid flowing between the first valve port P1 and the second valve port P2 is restricted.

Further, the valve member 30 is provided with a pressure equalizing path 36 that allows the rotary shaft portion mounting hole 32 of the cylindrical portion 31 to communicate with the sealed recess 34. By this pressure equalization path 36, the sealed space G (that is, the first valve port P 1 or the second valve port P 2 that is opened and closed by the valve body 33) and the back pressure chamber H through the rotation shaft portion mounting hole 32 and the back pressure chamber H Are connected and connected. In the present embodiment, the pressure equalizing path 36 is provided in the valve member 30, but is not limited to this. For example, in a configuration in which the valve member 30 opens and closes only the first valve port P1, for example, a pressure equalizing path that connects the first valve port P1 and the back pressure chamber H may be provided in the valve body 10.

When the valve member 30 is in the first stop position shown in FIG. 3 (a), neither the first valve port P1 nor the second valve port P2 is covered by the valve body 33, and the first valve port P1 The second valve port P2 is exposed in the valve chamber B and fluid flow is allowed (valve open state).

Further, when the valve member 30 is rotated clockwise from the first stop position shown in FIG. 3A to the second stop position shown in FIG. Valve port P1 is covered. Thereby, the first valve port P1 is exposed in the sealed space G, the second valve port P2 is exposed in the valve chamber B, and the first valve port P1 or the second valve port P2 is separated from each other, The flow of fluid flowing between the first valve port P1 and the second valve port P2 is restricted (valve closed state).

Further, when the valve member 30 is rotated counterclockwise in the drawing from the first stop position of FIG. 3A to the third stop position shown in FIG. The two-valve port P2 is covered. Thereby, the second valve port P2 is exposed in the sealed space G, the first valve port P1 is exposed in the valve chamber B, and the first valve port P1 or the second valve port P2 is separated from each other, The flow of fluid flowing between the first valve port P1 and the second valve port P2 is restricted (valve closed state).

The valve body 10 and the valve member 30 restrict the valve member 30 from being rotated clockwise beyond the second stop position and from being rotated counterclockwise beyond the third stop position. A pair of rotation stopper mechanisms (not shown) are provided. Alternatively, a detection unit including a sensor that detects the rotation angle of the valve member 30 is provided, and the valve member 30 is moved to the second stop position and the second position based on the rotation angle of the valve member 30 detected by the detection unit. The structure etc. which control the rotational drive part 50 mentioned later so that it may stop at 3 stop positions may be sufficient.

The rotary shaft portion 40 is formed in a columnar shape, one end portion 41 is attached to the valve member 30, and the other end portion 42 penetrates the second portion 12 of the valve body 10 and protrudes to the outside. Further, the central portion 43 of the rotation shaft portion 40 is rotated by the bearing portion 16 provided in the second portion 12 of the valve body 10 so that the shaft of the rotation shaft portion 40 overlaps the axis L of the circular through hole 13. Supported as possible.

The one end 41 of the rotating shaft 40 is inserted inside the coil spring 63 and is inserted into the rotating shaft mounting hole 32 of the valve member 30. At this time, the coil spring 63 is compressed between a flange-shaped spring receiving portion 44 provided in the rotating shaft portion 40 and a step portion 32c between the small diameter portion 32a and the large diameter portion 32b in the rotating shaft portion mounting hole 32. It is sandwiched between states. Accordingly, the valve member 30 is pressed toward the valve seat surface 22a by the coil spring 63. The coil spring 63 corresponds to an example of a pressing member.

Further, one end portion 41 of the rotating shaft portion 40 is provided with a convex portion (not shown) formed on the outer peripheral surface thereof, and this convex portion is formed on the inner peripheral surface of the small diameter portion 32a of the rotating shaft portion mounting hole 32. Is provided with a recess (not shown) formed so as to be locked in the rotation direction about the axis L. Thereby, the rotating shaft 40 can move in the direction of the axis L with respect to the valve member 30, and when the rotating shaft 40 is rotated about the axis L, the protrusion and the recess are engaged. The valve member 30 is rotated together with the rotating shaft portion 40.

The rotary shaft portion 40 is provided with a first flange portion 45 spaced above the spring receiving portion 44 in the drawing, and a second flange portion 46 spaced above the first flange portion 45 in the drawing. It has been. The outer diameters of the first flange portion 45 and the second flange portion 46 are substantially the same as the inner diameter of the bearing portion 16 of the valve body 10. A first seal ring 61 is disposed between the spring receiving portion 44 and the first flange portion 45, and a second seal ring 62 is disposed between the first flange portion 45 and the second flange portion 46. The first seal ring 61 and the second seal ring 62 seal the gap between the bearing portion 16 and the rotary shaft portion 40.

The first seal ring 61 and the second seal ring 62 are made of a relatively soft elastic material such as nitrile rubber or silicone rubber, for example. The first seal ring 61 and the second seal ring 62 are formed in an annular shape (ring shape) in a state where no force is applied from the outside (a state in which the second seal ring 62 is not elastically deformed), and the inner diameter thereof is rotated. The outer diameter of the central portion 43 of the shaft portion 40 is slightly smaller and the outer diameter is slightly larger than the inner diameter of the bearing portion 16.

The rotation drive part 50 is provided in the vicinity of the location where the rotary shaft part 40 protrudes on the upper surface 12a of the second part 12 of the valve body 10. The rotation drive unit 50 includes a motor unit 51 formed of a DC motor, a first gear 52 fixedly attached to a motor shaft 51 a of the motor unit 51, and the rotation shaft unit 40 so as to mesh with the first gear 52. And a second gear 53 fixedly attached to the end portion 42. When electric power is supplied to the motor unit 51, the rotation drive unit 50 rotates the motor shaft 51 a, and this rotation rotates the rotation shaft unit 40 about the axis L through the first gear 52 and the second gear 53. Let In the present embodiment, the speed reduction mechanism is configured by a pair of gears (the first gear 52 and the second gear 53), but the speed reduction mechanism may be configured by more gears. This reduction mechanism may be constituted by a planetary gear.

Next, an example of the operation of the two-way valve 1 of the present embodiment will be described with reference to FIGS.

FIG. 4 is a diagram for explaining a portion of the valve member that receives the fluid pressure in the sealed space of the valve body, and FIG. 4A is a cross-sectional view of the valve member when the sealed space of the valve body is maximized. (B) is a plan view of the valve seat surface viewed from the direction of the axis L in the configuration including the valve member of (a) (maximum configuration in the sealed space). FIG. 5 is a diagram for explaining a portion that receives the fluid pressure in the sealed space of the valve body in the valve member, and (a) is a cross-sectional view of the valve member when the sealed space of the valve body is minimized. (B) is a plan view of the valve seat surface as viewed from the direction of the axis L in the configuration including the valve member of (a) (minimum configuration in the sealed space).

6A and 6B are diagrams for explaining the operation of the two-way valve in FIG. 1, wherein FIG. 6A is a longitudinal sectional view of the two-way valve, and FIG. (C) is an enlarged cross-sectional view enlarging a part of (a) (case 1: in the maximum configuration of the sealed space, the fluid pressure in the sealed space and the back pressure chamber is the valve). When the fluid pressure in the room is higher). 7A and 7B are views for explaining the operation of the two-way valve in FIG. 1, wherein FIG. 7A is a longitudinal sectional view of the two-way valve, and FIG. 7B is a view illustrating the valve seat surface of FIG. (C) is an enlarged cross-sectional view enlarging a part of (a) (Case 2: In the minimum configuration of the sealed space, the fluid pressure in the sealed space and the back pressure chamber is the valve When the fluid pressure in the room is higher). 8A and 8B are views for explaining the operation of the two-way valve in FIG. 1, wherein FIG. 8A is a longitudinal sectional view of the two-way valve, and FIG. 8B is a view illustrating the valve seat surface of FIG. (C) is an enlarged cross-sectional view enlarging a part of (a) (case 3: in the maximum configuration of the sealed space, the fluid pressure in the sealed space and the back pressure chamber is controlled by the valve). If lower than fluid pressure in the room). 9A and 9B are views for explaining the operation of the two-way valve in FIG. 1, wherein FIG. 9A is a longitudinal sectional view of the two-way valve, and FIG. 9B is a view of the valve seat surface of FIG. (C) is an enlarged cross-sectional view enlarging a part of (a) (case 4: in the minimum configuration of the sealed space, the fluid pressure in the sealed space and the back pressure chamber is controlled by the valve). If lower than fluid pressure in the room).

In the above-described two-way valve 1, for example, the contact area between the lower end surface 33a of the valve member 30 and the valve seat surface 22a varies or is unstable due to various factors such as the shape tolerance of the valve member 30 and distortion due to temperature change. The balance of force due to the fluid pressure applied to the valve member 30 changes. Therefore, the case where the sealed space G becomes the maximum and the minimum due to the variation in the contact area between the lower end surface 33a of the valve member 30 and the valve seat surface 22a is the worst case. By setting a force to press the valve member 30 by the coil spring 63 so as not to float from the valve seat surface 22a, the valve member 30 is prevented from floating from the valve seat surface 22a in all assumed cases. Is possible.

For example, as shown in FIG. 4A, when the valve member 30 is pressed against the valve seat surface 22 a by the coil spring 63, the outer peripheral edge 33 a 1 of the lower end surface 33 a of the valve body portion 33 is It is conceivable that the inner peripheral edge 33a2 is in contact with the surface 22a and is separated from the valve seat surface 22a. In this case, the fluid pressure in the sealed space G is applied to the lower end surface 33 a of the valve body 33. That is, as shown in FIG. 4B, the planar view area S1 of the location where the fluid pressure in the sealed space G in the valve member 30 is applied is the area within the outer peripheral edge 33a1 of the lower end surface 33a of the valve body 33 ( (Hatched area). Hereinafter, this configuration is referred to as a “closed space maximum configuration”.

As shown in FIG. 5A, when the valve member 30 is pressed against the valve seat surface 22a by the coil spring 63, the inner peripheral edge 33a2 of the lower end surface 33a of the valve body portion 33 is not It is conceivable that the outer peripheral edge 33a1 is in contact with the surface 22a and is separated from the valve seat surface 22a. In this case, the fluid pressure in the valve chamber B is applied to the lower end surface 33 a of the valve body portion 33. That is, as shown in FIG. 5B, the planar view area S 2 of the location where the fluid pressure in the sealed space G in the valve member 30 is applied is the area within the inner peripheral edge 33 a 2 of the lower end surface 33 a of the valve body portion 33 ( (Hatched area). Hereinafter, this configuration is referred to as a “closed space minimum configuration”.

And in each of these sealed space maximum configuration and sealed space minimum configuration, about the four cases when the fluid pressure in the sealed space G and the back pressure chamber H is higher and lower than the fluid pressure in the valve chamber B, An example of the force acting on the valve member 30 is shown below.

In the following description, the planar view area SH1 of the large diameter cylindrical portion 31b of the cylindrical portion 31 of the valve member 30 is 380 square millimeters (that is, the diameter D1 of the large diameter cylindrical portion 31b is 22 mm), and the planar view area of the small diameter cylindrical portion 31a. SH2 is 254.3 square millimeters (that is, the diameter D2 of the small-diameter cylindrical portion 31a is 18 mm), and the planar view area S1 (that is, the area in the outer peripheral edge 33a1 of the lower end surface 33a) when the sealed space is maximum is 385 square. The plane view area S2 (that is, the area in the inner peripheral edge 33a2 of the lower end surface 33a) in the case of the millimeter and the sealed space minimum configuration is 250 square millimeters.

The force F1 acting on the valve member 30 by the fluid pressure in the sealed space G is caused by the pressure difference between the fluid pressure in the sealed space G and the fluid pressure in the valve chamber B (the pressure difference ΔP1 or ΔP2). It is obtained by multiplying the plane view area (the plane view area S1 or S2) of the location where the fluid pressure in the sealed space G at 30 is applied. The force F2 acting on the valve member 30 by the fluid pressure in the back pressure chamber H is a pressure difference between the fluid pressure in the back pressure chamber H and the fluid pressure in the valve chamber B (the pressure difference ΔP1 or ΔP2). It is obtained by multiplying the planar view area (the planar view area SH1 or SH2) of the location where the fluid pressure in the back pressure chamber H in the valve member 30 is applied. In the following, the direction in which the valve member 30 is pressed against the valve seat surface is positive.

(Case 1: When the fluid pressure in the sealed space G and the back pressure chamber H is higher than the fluid pressure in the valve chamber B in the maximum configuration of the sealed space)
As shown in FIGS. 6A and 6B, when the fluid pressure in the sealed space G and the back pressure chamber H is higher than the fluid pressure in the valve chamber B, the seal ring 38 is the cylindrical portion of the valve member 30. 31 is pressed against the stepped surface 31c of the cylindrical portion. Therefore, the fluid pressure in the back pressure chamber H is applied to the location of the large-diameter cylindrical portion 31b (that is, the planar view area SH1). Therefore, the force F1 acting on the valve member 30 by the fluid pressure in the sealed space G is
F1 = (− ΔP1) × S1 = −1155 [N] (2-1)
The force F2 acting on the valve member 30 due to the fluid pressure in the back pressure chamber H is
F2 = ΔP1 × SH1 = 1140 [N] (2-2)
It becomes. Therefore, from the above formula, the valve member 30 has
F = F1 + F2 = −15 [N]
That is, a force of 15 [N] is working to lift the valve member 30 from the valve seat surface 22a. In this case, it is necessary to press the valve member 30 toward the valve seat surface 22 a with a force exceeding at least 15 [N] by the coil spring 63.

(Case 2: When the fluid pressure in the sealed space G and the back pressure chamber H is higher than the fluid pressure in the valve chamber B in the minimum configuration of the sealed space)
As shown in FIGS. 7A and 7B, in the case 2 as well, as in the case 1, the fluid pressure in the back pressure chamber H is at the location of the large-diameter cylindrical portion 31b (that is, the plan view area SH1). Join. Therefore, the force F1 acting on the valve member 30 by the fluid pressure in the sealed space G is
F1 = (− ΔP1) × S2 = −750 [N] (2-3)
The force F2 acting on the valve member 30 due to the fluid pressure in the back pressure chamber H is
F2 = ΔP1 × SH1 = 1140 [N] (2-4)
It becomes. Therefore, from the above formula, the valve member 30 has
F = F1 + F2 = 390 [N]
That is, a force of 390 [N] is acting so as to press the valve member 30 against the valve seat surface 22a. In this case, even if the valve member 30 is not pressed against the valve seat surface 22a by the coil spring 63, the valve member 30 does not rise from the valve seat surface 22a.

(Case 3: When the fluid pressure in the sealed space G and the back pressure chamber H is lower than the fluid pressure in the valve chamber B in the maximum configuration of the sealed space)
As shown in FIGS. 8A and 8B, when the fluid pressure in the sealed space G and the back pressure chamber H is lower than the fluid pressure in the valve chamber B, the seal ring 38 is the valve member of the valve body 10. It is pressed against the support portion step surface 15 c of the support portion 15. For this reason, the fluid pressure in the back pressure chamber H is applied to the small-diameter cylindrical portion 31a (that is, the planar view area SH2). Therefore, the force F1 acting on the valve member 30 by the fluid pressure in the sealed space G is
F1 = (− ΔP2) × S1 = 1155 [N] (2-5)
The force F2 acting on the valve member 30 due to the fluid pressure in the back pressure chamber H is
F2 = ΔP2 × SH2 = −763 [N] (2-6)
It becomes. Therefore, from the above formula, the valve member 30 has
F = F1 + F2 = 392 [N]
In other words, a force of 392 [N] acts so as to press the valve member 30 against the valve seat surface 22a. In this case, even if the valve member 30 is not pressed against the valve seat surface 22a by the coil spring 63, the valve member 30 does not rise from the valve seat surface 22a.

(Case 4: When the fluid pressure in the sealed space G and the back pressure chamber H is lower than the fluid pressure in the valve chamber B in the minimum configuration of the sealed space)
As shown in FIGS. 9A and 9B, also in the case 4, as in the case 3, the fluid pressure in the back pressure chamber H is applied to the portion of the small-diameter cylindrical portion 31a (that is, the planar view area SH2). . Therefore, the force F1 acting on the valve member 30 by the fluid pressure in the sealed space G is
F1 = (− ΔP2) × S2 = 750 [N] (2-7)
The force F2 acting on the valve member 30 due to the fluid pressure in the back pressure chamber H is
F2 = ΔP2 × SH2 = −763 [N] (2-8)
It becomes. Therefore, from the above formula, the valve member 30 has
F = F1 + F2 = −13 [N]
That is, a force of 13 [N] is working to lift the valve member 30 from the valve seat surface 22a. In this case, it is necessary to press the valve member 30 toward the valve seat surface 22a with a force exceeding at least 13 [N] by the coil spring 63.

Among the cases 1 to 4 described above, in the case 1, the force that the valve member 30 lifts from the valve seat surface 22a is the largest. Therefore, in order to prevent the valve member 30 from floating from the valve seat surface 22a in any of the cases 1 to 4, the valve member 30 is not lifted from the valve seat surface 22a in case 1, which is the worst case. What should I do? That is, the force FS for pressing the valve member 30 by the coil spring 63 toward the valve seat surface 22a may be set so as to at least exceed 15 [N], which is a force for lifting the valve member 30 in the case 1. Then, when the relationship between the fluid pressure in the back pressure chamber H and the fluid pressure in the valve chamber B is switched, the planar view area to which the fluid pressure in the back pressure chamber H in the valve member 30 is applied changes. Specifically, the plane view area SH2 when the fluid pressure in the valve chamber B is higher than the fluid pressure in the back pressure chamber H is the plane when the fluid pressure in the valve chamber B is lower than the fluid pressure in the back pressure chamber H. It becomes smaller than the viewing area SH1. Thereby, the force set to this coil spring 63 becomes small compared with the conventional structure.

As described above, in the two-way valve 1, when the fluid pressure in the sealed space G and the back pressure chamber H is higher than the fluid pressure in the valve chamber B, the seal ring 38 is the cylinder of the column portion 31 of the valve member 30. It is pressed against the part step surface 31c. Therefore, the fluid pressure in the back pressure chamber H is applied to the location of the large-diameter cylindrical portion 31b (that is, the planar view area SH1). Further, when the fluid pressure in the sealed space G and the back pressure chamber H is lower than the fluid pressure in the valve chamber B, the seal ring 38 is pressed against the support portion step surface 15 c of the valve member support portion 15 of the valve body 10. . For this reason, the fluid pressure in the back pressure chamber H is applied to the small-diameter cylindrical portion 31a (that is, the planar view area SH2).

That is, the two-way valve 1 has a back pressure chamber H having a planar view area SH2 to which the fluid pressure of the back pressure chamber H in the valve member 30 when the fluid pressure of the back pressure chamber H is lower than the fluid pressure of the valve chamber B is applied. Is smaller than the planar view area SH1 when the fluid pressure is higher than the fluid pressure in the valve chamber B. An annular seal ring 38 that seals between the valve body 10 and the valve member 30 is provided between the valve body 10 and the valve member 30. When the fluid pressure in the back pressure chamber H is higher than the fluid pressure in the valve chamber B, the seal ring 38 is pressed against the valve member 30, and the seal ring 38 is pressed against the valve body 10 when the fluid pressure in the back pressure chamber H is lower than the fluid pressure in the valve chamber B.

As described above, the two-way valve 1 of the present embodiment opens to the valve body 10 in which the space Q is provided inside, the planar valve seat surface 22a facing the space Q, and the valve seat surface 22a. A valve seat portion 20 having a first valve port P1 and a second valve port P2, a first valve port P1 which is disposed in the space Q so as to be slidably rotatable on the valve seat surface 22a, and is determined according to a stop position. A valve member 30 that switches the communication relationship of the second valve port P2 by rotation and a coil spring 63 that presses the valve member 30 toward the valve seat surface 22a are provided. In addition, the valve member 30 is connected to the column body 31 rotatably supported by the valve body 10 about the axis, and one end of the column portion 31, and the first valve port P 1 and the first valve port P 1 are arranged according to the stop position of the valve member 30. And a valve body portion 33 for opening and closing the two-valve port P2. The valve body 10 is formed on the other end side of the cylindrical portion 31 and the valve chamber B in which the valve body portion 33 formed on one end side of the cylindrical portion 31 is accommodated by dividing the space Q by the valve member 30. A back pressure chamber H. The valve member 30 has a pressure equalizing path 36 that connects the first valve port P1 and the second valve port P2 to the back pressure chamber H. The cylindrical portion 31 includes a small-diameter cylindrical portion 31a arranged so that one end surface faces the back pressure chamber H, a large-diameter cylindrical portion 31b coaxially connected to the other end surface of the small-diameter cylindrical portion 31a, and a small-diameter cylindrical portion 31a. A cylindrical stepped surface 31c formed between the outer peripheral surface 31a1 and the outer peripheral surface 31b1 of the large-diameter cylindrical portion 31b. The valve body 10 includes a small-diameter hole portion 15a into which the small-diameter cylindrical portion 31a is rotatably fitted, a large-diameter hole portion 15b into which the large-diameter cylindrical portion 31b is rotatably fitted, and an inner circumference of the small-diameter hole portion 15a. The valve member support portion 15 is provided with a support stepped surface 15c formed between the surface 15a1 and the inner peripheral surface 15b1 of the large-diameter hole portion 15b. The outer peripheral surface of the small-diameter cylindrical portion 31a is placed in the seal space R surrounded by the outer peripheral surface 31a1, the cylindrical stepped surface 31c, the inner peripheral surface 15b1 of the large-diameter hole 15b, and the support stepped surface 15c. An annular seal ring 38 is provided for sealing between 31a1 and the inner peripheral surface 15b1 of the large-diameter hole 15b.

As described above, according to the present embodiment, the cylindrical portion 31 supported by the valve body 10 so as to be rotatable about the axis is a small-diameter cylindrical portion 31a disposed so that one end surface faces the back pressure chamber H, A large-diameter cylindrical portion 31b coaxially connected to the other end surface of the small-diameter cylindrical portion 31a, a cylindrical step surface 31c formed between the outer peripheral surface 31a1 of the small-diameter cylindrical portion 31a and the outer peripheral surface 31b1 of the large-diameter cylindrical portion 31b; have. The valve body 10 includes a small-diameter hole portion 15a in which the small-diameter cylindrical portion 31a of the cylindrical portion 31 is rotatably fitted, and a large-diameter hole portion in which the large-diameter cylindrical portion 31b of the cylindrical portion 31 is rotatably fitted. 15b, and a valve member support portion 15 provided with a support stepped surface 15c formed between the inner peripheral surface 15a1 of the small diameter hole portion 15a and the inner peripheral surface 15b1 of the large diameter hole portion 15b. Yes. The cylindrical portion 31 is surrounded by the outer peripheral surface 31a1 of the small-diameter cylindrical portion 31a, the cylindrical stepped surface 31c, the inner peripheral surface 15b1 of the large-diameter hole portion 15b of the valve member supporting portion 15 of the valve body 10, and the supporting portion stepped surface 15c. In the sealed space R, an annular seal ring 38 is provided for sealing between the outer peripheral surface 31a1 of the small diameter cylindrical portion 31a and the inner peripheral surface 15b1 of the large diameter hole portion 15b. As a result, the fluid pressure in the valve chamber B is applied to a portion of the seal ring 38 on the columnar step surface 31c side, and a back pressure chamber is applied to the portion of the seal ring 38 on the support step surface 15c side. Fluid pressure in H is applied. Therefore, when the fluid pressure in the back pressure chamber H is higher than the fluid pressure in the valve chamber B, the seal ring 38 is pressed against the cylindrical portion step surface 31 c by the fluid pressure in the back pressure chamber H, and the valve member 30 is flat. The fluid pressure in the back pressure chamber H is applied to a location inside the outer diameter of the large-diameter cylindrical portion 31b as viewed. Further, when the fluid pressure in the back pressure chamber H is lower than the fluid pressure in the valve chamber B, the seal ring 38 is pressed against the support portion step surface 15 c by the fluid pressure in the valve chamber B, and the valve member 30 is viewed in plan view. Thus, the fluid pressure in the back pressure chamber H is applied to a location inside the outer diameter of the small diameter cylindrical portion 31a. That is, when the fluid pressure in the back pressure chamber H is lower than the fluid pressure in the valve chamber B, the force that causes the valve member 30 to lift from the valve seat surface 22a is exerted by the fluid pressure in the back pressure chamber H. However, since the area of the portion of the valve member 30 where the fluid pressure in the back pressure chamber H is applied is reduced, the force to lift the valve member 30 from the valve seat surface 22a can be reduced. Thereby, since the force which presses the valve member 30 by the coil spring 63 toward the valve seat surface 22a can be made small, the force which presses the valve member 30 to the valve seat surface 22a can be suppressed.

Further, the two-way valve 1 has a back pressure chamber H having a plan view area SH2 to which the fluid pressure of the back pressure chamber H in the valve member 30 when the fluid pressure of the back pressure chamber H is lower than the fluid pressure of the valve chamber B is applied. Is configured to be smaller than the planar view area SH1 when the fluid pressure is higher than the fluid pressure in the valve chamber B. Thus, when the fluid pressure in the back pressure chamber H is lower than the fluid pressure in the valve chamber B, the fluid pressure in the back pressure chamber H causes the valve member 30 to lift from the valve seat surface 22a. When the force is working, the area of the valve member 30 where the fluid pressure in the back pressure chamber H is applied (that is, the area in plan view) is reduced, so that the force to lift the valve member 30 from the valve seat surface 22a is increased. Can be small. Thereby, since the force which presses the valve member 30 by the coil spring 63 toward the valve seat surface 22a can be made small, the force which presses the valve member 30 to the valve seat surface 22a can be suppressed.

Further, the two-way valve 1 is provided with an annular seal ring 38 between the valve body 10 and the valve member 30 to seal between them. The seal ring 38 is pressed against the valve member 30 when the fluid pressure in the back pressure chamber H is higher than the fluid pressure in the valve chamber B, and the seal is sealed when the fluid pressure in the back pressure chamber H is lower than the fluid pressure in the valve chamber B. The ring 38 is configured to be pressed against the valve body 10. Because of this, the annular seal ring 38 that seals between the valve body 10 and the valve member 30 has a fluid pressure in the back pressure chamber H on a part of the surface (location on the support step surface 15c side). Is added, and the fluid pressure in the valve chamber B is applied to the other part of the surface (location on the cylindrical stepped surface 31c side). When the seal ring 38 is pressed against the valve member 30 when the fluid pressure in the back pressure chamber H is higher than the fluid pressure in the valve chamber B, the back pressure applied to the planar view area of a part of the surface of the seal ring 38 is increased. The fluid pressure in chamber H is also applied to valve member 30. Further, when the seal ring 38 is pressed against the valve body 10 when the fluid pressure in the back pressure chamber H is lower than the fluid pressure in the valve chamber B, the valve chamber B applied to the other part of the surface of the seal ring 38 Fluid pressure is also applied to the valve body 10. That is, when the fluid pressure in the back pressure chamber H is lower than the fluid pressure in the valve chamber B, the planar view area SH2 to which the fluid pressure in the back pressure chamber H in the valve member 30 is applied (that is, directly or indirectly through the seal member). The planar view area to be applied) is configured to be smaller than the planar view area SH1 when the fluid pressure in the back pressure chamber H is higher than the fluid pressure in the valve chamber B. Therefore, when the fluid pressure in the back pressure chamber H is lower than the fluid pressure in the valve chamber B, the force that lifts the valve member 30 from the valve seat surface 22a by the fluid pressure in the back pressure chamber H works. However, since the area of the valve member 30 where the fluid pressure in the back pressure chamber H is applied (that is, the area in plan view) is reduced, the force to lift the valve member 30 from the valve seat surface 22a is reduced. Can do. Thereby, since the force which presses the valve member 30 by the coil spring 63 toward the valve seat surface 22a can be made small, the force which presses the valve member 30 to the valve seat surface 22a can be suppressed.

(Second Embodiment)
Hereinafter, the configuration of a flow path switching valve as a second embodiment of the rotary valve device of the present invention will be described with reference to FIGS. 10 and 11, and the operation will be described with reference to FIGS. .

FIG. 10 is a longitudinal sectional view of a flow path switching valve according to the second embodiment of the present invention. 11 is a cross-sectional view taken along the line XX of FIG. 10, in which (a) shows a state where the valve member is in the first stop position, and (b) shows that the valve member is in the second stop position. Indicates the state. Note that the concept of “upper and lower” in the following description corresponds to the upper and lower sides in FIG. 11 and indicates the relative positional relationship between the members, and does not indicate the absolute positional relationship.

The flow path switching valve (indicated by reference numeral 1A in each figure) of the second embodiment is disposed in, for example, a circuit in which the fluid flow direction changes, and is used for switching the fluid flow direction. It is a valve.

As shown in FIGS. 10 and 11, the flow path switching valve 1A of the present embodiment includes a valve body 10, a valve seat portion 20A, a valve member 30A, a seal ring 38, a rotary shaft portion 40, and a rotational drive. A portion 50 and a coil spring 63 are included. 1 A of flow-path switching valves of this embodiment are the same except having the valve seat part 20A and the valve member 30A instead of the valve seat part 20 and the valve member 30 in the two-way valve 1 of 1st Embodiment mentioned above. It is the composition. Therefore, in the following description, the same components as those of the first embodiment are denoted by the same reference numerals and description thereof is omitted.

20 A of valve seat parts are the valve seat part main body 21 integrally provided with the said 1st part 11 so that the other end part of the lower part of the 1st part 11 of the valve main body 10 in the figure may be plugged in, and the valve seat part main body 21 And a thin plate member 22 fixedly stacked on a plane facing the space Q side.

Further, the valve seat portion 20A includes a first fixed port E1, a second fixed port E2, a first switching port C1, and a plurality of valve ports provided through the valve seat portion main body 21 and the thin plate member 22. A second switching port C2 is provided. In the present embodiment, the first fixed port E1 is disposed so as to overlap the axis L of the circular through-hole 13 in a plan view from the direction orthogonal to the valve seat surface 22a, and the second fixed port E2 and the first switching port C1. And the 2nd switching port C2 is arrange | positioned on the circumference (substantially circumference is included) centering on the axis | shaft L. As shown in FIG. The valve seat portion main body 21 and the thin plate member 22 of the valve seat portion 20A have the same configuration as that of the first embodiment described above except for the opened port.

The valve member 30 A integrally includes a cylindrical portion 31 and a valve body portion 33 A provided at the lower end of the cylindrical portion 31 in the drawing (that is, one end of the cylindrical portion 31). The valve member 30 A is accommodated in the space Q in the valve body 10. The cylindrical portion 31 has the same configuration as that of the first embodiment described above. That is, the cylindrical portion 31 and the valve member support portion 15 of the valve body 10 of the present embodiment have the same configuration as that of the first embodiment described above shown in FIG.

The valve body portion 33 A is formed in a circular shape in a plan view projecting in the radial direction of the cylindrical portion 31, and is disposed in the inner space 11 a of the valve body 10. In the present embodiment, the valve body portion 33 A is provided integrally with one end of the column portion 31. Of course, in addition to this configuration, the valve body portion 33A may be formed separately from the cylindrical portion 31 and provided continuously to one end of the cylindrical portion 31 via a connecting member or the like. The lower end surface 33a of the valve body portion 33A is formed in a flat shape, and is closely overlapped with the valve seat surface 22a of the valve seat portion 20A so as to be slidable and rotatable. The lower end surface 33a of the valve body 33A is provided with a sealed communication path 34A and an open communication path 35 that extend inside the valve body 33A.

The sealed communication path 34A is provided on the lower end surface 33a of the valve body portion 33A so as to extend in the radial direction from the central portion so as to form a sealed space G1 between the sealed communication passage 34A and the valve seat surface 22a. In the present embodiment, the sealed communication passage 34 A is formed in a band shape (including a substantially band shape) in a plan view as viewed from the direction of the axis L, and an extending portion 340 extending in one direction on the outer side of the cylindrical portion 31. Have.

The open communication path 35 is provided in the lower end surface 33a of the valve body 33A so as to form a substantially C-shaped space G2 surrounding the sealed communication path 34A. The valve body 33A is provided with a connection hole 33b for connecting the inside and outside of the open communication passage 35.

Further, the valve member 30A is provided with a pressure equalizing path 36 that communicates the rotating shaft portion mounting hole 32 of the cylindrical portion 31 and the sealed communication path 34A. By this pressure equalizing path 36, the sealed space G 1 of the sealed communication path 34 A and the back pressure chamber H are communicated and connected through the rotating shaft portion mounting hole 32.

When the valve member 30A is in the first stop position shown in FIG. 11 (a), the first fixed port E1 and the first switching port C1 are connected in communication by the sealed space G1 of the sealed communication path 34A, and The second fixed port E2 and the second switching port C2 are exposed in the space G2 of the open communication path 35 to connect and connect these ports. Further, when the valve member 30A is rotated from the first stop position shown in FIG. 11A to the second stop position shown in FIG. 11B, the valve member 30A becomes the first fixed port by the sealed space G1 formed by the sealed communication path 34A. E1 and the second switching port C2 are connected in communication, and the second fixed port E2 and the first switching port C1 are exposed in the space G2 of the open communication path 35 to connect and connect these ports.

The valve body 10 and the valve member 30A are provided with a pair of rotation stopper mechanisms (not shown) that restrict the valve member 30A from rotating beyond the first stop position and the second stop position. Alternatively, a detection unit including a sensor that detects the rotation angle of the valve member 30A is provided, and the valve member 30A is moved to the first stop position and the first position based on the rotation angle of the valve member 30A detected by the detection unit. 2 The structure etc. which control the rotational drive part 50 mentioned later so that it may stop at a stop position may be sufficient. Thereby, the valve member 30A is rotated counterclockwise in the figure from the first stop position and stopped at the second stop position, and is rotated clockwise in the figure from the second stop position to stop at the first stop position. .

Next, an example of the operation in the flow path switching valve 1A of the present embodiment will be described with reference to FIGS.

FIG. 12 is a diagram for explaining a portion that receives the fluid pressure in the sealed space of the valve body in the valve member, and (a) is a cross-sectional view of the valve member when the sealed space of the valve body is maximized. (B) is a plan view of the valve seat surface viewed from the direction of the axis L in the configuration including the valve member of (a) (maximum configuration in the sealed space). FIG. 13 is a diagram for explaining a portion that receives the fluid pressure in the sealed space of the valve body part in the valve member, and (a) is a cross-sectional view of the valve member when the sealed space of the valve body part is minimized. (B) is a plan view of the valve seat surface as viewed from the direction of the axis L in the configuration including the valve member of (a) (minimum configuration in the sealed space).

FIG. 14 is a diagram for explaining the operation of the flow path switching valve of FIG. 10, wherein (a) is a longitudinal sectional view of the flow path switching valve, and (b) is a view of the valve seat surface of (a). It is the top view seen from the direction of an axis | shaft L, (c) is an expanded sectional view which expanded a part of (a) (Case 1: Fluid pressure in sealed space and back pressure chamber in sealed space maximum configuration) Is higher than the fluid pressure in the valve chamber). 15 is a view for explaining the operation of the flow path switching valve of FIG. 10, wherein (a) is a longitudinal sectional view of the flow path switching valve, and (b) is a view of the valve seat surface of (a). It is the top view seen from the direction of an axis | shaft L, (c) is an expanded sectional view which expanded a part of (a) (Case 2: Fluid pressure in sealed space and back pressure chamber in sealed space minimum configuration) Is higher than the fluid pressure in the valve chamber). 16 is a diagram for explaining the operation of the flow path switching valve of FIG. 10, wherein (a) is a longitudinal sectional view of the flow path switching valve, and (b) is a view of the valve seat surface of (a). It is the top view seen from the direction of an axis | shaft L, (c) is an expanded sectional view which expanded a part of (a) (Case 3: Fluid pressure in sealed space and back pressure chamber in sealed space maximum configuration) Is lower than the fluid pressure in the valve chamber). FIG. 17 is a diagram for explaining the operation of the flow path switching valve of FIG. 10, wherein (a) is a longitudinal sectional view of the flow path switching valve, and (b) is a view of the valve seat surface of (a). It is the top view seen from the direction of an axis | shaft L, (c) is an expanded sectional view which expanded a part of (a) (Case 4: Fluid pressure in sealed space and back pressure chamber in sealed space minimum configuration) Is lower than the fluid pressure in the valve chamber).

In the above-described flow path switching valve 1A, for example, the contact area between the lower end surface 33a of the valve member 30A and the valve seat surface 22a varies due to various factors such as the shape tolerance of the valve member 30A and distortion due to temperature change. The balance of force due to the fluid pressure applied to the valve member 30A may change. Therefore, the case where the sealed space G1 is maximized or minimized due to variations in the contact area between the lower end surface 33a of the valve member 30A and the valve seat surface 22a is the worst case. By setting a force to press the valve member 30A by the coil spring 63 so as not to float from the valve seat surface 22a, the valve member 30 is prevented from floating from the valve seat surface 22a in all assumed cases. Is possible.

For example, as shown in FIG. 12A, when the valve member 30A is pressed against the valve seat surface 22a by the coil spring 63, the sealing communication passage 34A in the lower end surface 33a of the valve body portion 33A is surrounded by the shape tolerance. It is conceivable that the outer peripheral edge 33a3 of the portion is brought into contact with the valve seat surface 22a and the inner peripheral edge 33a4 of the portion is separated from the valve seat surface 22a. In this case, the fluid pressure in the sealed space G1 is applied to the portion of the lower end surface 33a of the valve body portion 33A. That is, as shown in FIG. 12 (b), the planar view area S1 of the location where the fluid pressure in the sealed space G1 of the valve member 30A is applied surrounds the sealed communication path 34A on the lower end surface 33a of the valve body 33A. It becomes an area (shaded part) in the outer peripheral edge 33a3. Hereinafter, this configuration is referred to as a “closed space maximum configuration”.

Further, as shown in FIG. 13A, when the valve member 30A is pressed against the valve seat surface 22a by the coil spring 63, the sealed communication passage 34A in the lower end surface 33a of the valve body portion 33A is surrounded by the shape tolerance. It is conceivable that the inner peripheral edge 33a4 of the portion is in contact with the valve seat surface 22a and the outer peripheral edge 33a3 of the portion is separated from the valve seat surface 22a. In this case, the fluid pressure in the valve chamber B is applied to the portion of the lower end surface 33a of the valve body portion 33A. That is, as shown in FIG. 13 (b), the planar view area S2 of the portion of the valve member 30A where the fluid pressure in the sealed space G1 is applied surrounds the sealed communication passage 34A on the lower end surface 33a of the valve body portion 33A. This is the area (shaded area) in the inner peripheral edge 33a4. Hereinafter, this configuration is referred to as a “closed space minimum configuration”.

And in each of these sealed space maximum configuration and sealed space minimum configuration, about the four cases where the fluid pressure in the sealed space G1 and the back pressure chamber H is higher and lower than the fluid pressure in the valve chamber B, An example of the force acting on the valve member 30A is shown below.

In the following description, the planar view area SH1 of the large diameter cylindrical portion 31b of the cylindrical portion 31 of the valve member 30A is 380 square millimeters (that is, the diameter D1 of the large diameter cylindrical portion 31b is 22 mm), and the planar view area of the small diameter cylindrical portion 31a. SH2 is 254.3 square millimeters (that is, the diameter D2 of the small-diameter cylindrical portion 31a is 18 mm), and the planar view area S1 (that is, the area in the outer peripheral edge 33a3 of the lower end surface 33a) is 400 squares when the sealed space is maximum. The plane view area S2 (that is, the area in the inner peripheral edge 33a4 of the lower end surface 33a) in the case of the millimeter and the sealed space minimum configuration is 252 square millimeters.

Further, when the fluid pressure in the sealed space G1 and the back pressure chamber H is higher than the fluid pressure in the valve chamber B, the pressure difference ΔP1 between these fluid pressures is set to 3.0 MPa, and the inside of the sealed space G1 and the back pressure chamber H The pressure difference ΔP2 between these fluid pressures when the fluid pressure is lower than the fluid pressure in the valve chamber B is −3.0 MPa.

The force F1 acting on the valve member 30A by the fluid pressure in the sealed space G1 is caused by the pressure difference between the fluid pressure in the sealed space G1 and the fluid pressure in the valve chamber B (the pressure difference ΔP1 or ΔP2). It is obtained by multiplying the planar view area (the planar view area S1 or S2) of the location where the fluid pressure in the sealed space G1 at 30A is applied. The force F2 acting on the valve member 30A due to the fluid pressure in the back pressure chamber H is a pressure difference between the fluid pressure in the back pressure chamber H and the fluid pressure in the valve chamber B (the pressure difference ΔP1 or ΔP2). It is obtained by multiplying the planar view area (the planar view area SH1 or SH2) of the location where the fluid pressure in the back pressure chamber H in the valve member 30A is applied. In the following description, the direction in which the valve member 30A is pressed against the valve seat surface 22a is positive.

(Case 1: When the fluid pressure in the sealed space G1 and the back pressure chamber H is higher than the fluid pressure in the valve chamber B in the maximum configuration of the sealed space)
As shown in FIGS. 14A and 14B, when the fluid pressure in the sealed space G1 and the back pressure chamber H is higher than the fluid pressure in the valve chamber B, the seal ring 38 is the cylindrical portion of the valve member 30A. 31 is pressed against the stepped surface 31c of the cylindrical portion. Therefore, the fluid pressure in the back pressure chamber H is applied to the location of the large-diameter cylindrical portion 31b (that is, the planar view area SH1). Therefore, the force F1 acting on the valve member 30A by the fluid pressure in the sealed space G1 is
F1 = (− ΔP1) × S1 = −1200 [N] (3-1)
The force F2 acting on the valve member 30A by the fluid pressure in the back pressure chamber H is
F2 = ΔP1 × SH1 = 1140 [N] (3-2)
It becomes. Therefore, from the above formula, the valve member 30A has
F = F1 + F2 = −60 [N]
That is, a force of 60 [N] is working to lift the valve member 30A from the valve seat surface 22a. In this case, it is necessary to press the valve member 30 A toward the valve seat surface 22 a with a force exceeding at least 60 [N] by the coil spring 63.

(Case 2: When the fluid pressure in the sealed space G1 and the back pressure chamber H is higher than the fluid pressure in the valve chamber B in the minimum configuration of the sealed space)
As shown in FIGS. 15 (a) and 15 (b), in the case 2 as well, as in the case 1, the fluid pressure in the back pressure chamber H is at the location of the large-diameter cylindrical portion 31b (that is, the planar view area SH1). Join. Therefore, the force F1 acting on the valve member 30A by the fluid pressure in the sealed space G1 is
F1 = (− ΔP1) × S2 = −756 [N] (3-3)
The force F2 acting on the valve member 30A by the fluid pressure in the back pressure chamber H is
F2 = ΔP1 × SH1 = 1140 [N] (3-4)
It becomes. Therefore, from the above formula, the valve member 30A has
F = F1 + F2 = 384 [N]
In other words, a force of 384 [N] acts so as to press the valve member 30A against the valve seat surface 22a. In this case, even if the valve member 30A is not pressed toward the valve seat surface 22a by the coil spring 63, the valve member 30A does not float from the valve seat surface 22a.

(Case 3: When the fluid pressure in the sealed space G1 and the back pressure chamber H is lower than the fluid pressure in the valve chamber B in the maximum configuration of the sealed space)
16A and 16B, when the fluid pressure in the sealed space G1 and the back pressure chamber H is lower than the fluid pressure in the valve chamber B, the seal ring 38 is used as the valve member of the valve body 10. It is pressed against the support portion step surface 15 c of the support portion 15. For this reason, the fluid pressure in the back pressure chamber H is applied to the small-diameter cylindrical portion 31a (that is, the planar view area SH2). Therefore, the force F1 acting on the valve member 30A by the fluid pressure in the sealed space G1 is
F1 = (− ΔP2) × S1 = 1200 [N] (3-5)
The force F2 acting on the valve member 30A by the fluid pressure in the back pressure chamber H is
F2 = ΔP2 × SH2 = −763 [N] (3-6)
It becomes. Therefore, from the above formula, the valve member 30A has
F = F1 + F2 = 437 [N]
That is, the force of 437 [N] acts so as to press the valve member 30A against the valve seat surface 22a. In this case, even if the valve member 30A is not pressed toward the valve seat surface 22a by the coil spring 63, the valve member 30A does not float from the valve seat surface 22a.

(Case 4: When the fluid pressure in the sealed space G1 and the back pressure chamber H is lower than the fluid pressure in the valve chamber B in the minimum configuration of the sealed space)
As shown in FIGS. 17 (a) and 17 (b), in the case 4 as well, as in the case 3, the fluid pressure in the back pressure chamber H is applied to the portion of the small-diameter cylindrical portion 31a (that is, the planar view area SH2). . Therefore, the force F1 acting on the valve member 30A by the fluid pressure in the sealed space G1 is
F1 = (− ΔP2) × S2 = 756 [N] (3-7)
The force F2 acting on the valve member 30A by the fluid pressure in the back pressure chamber H is
F2 = ΔP2 × SH2 = −763 [N] (3-8)
It becomes. Therefore, from the above formula, the valve member 30A has
F = F1 + F2 = −7 [N]
That is, a force of 7 [N] is working to lift the valve member 30A from the valve seat surface 22a. In this case, it is necessary to press the valve member 30 A toward the valve seat surface 22 a with a force exceeding at least 7 [N] by the coil spring 63.

Among the cases 1 to 4 described above, in the case 1, the force that the valve member 30A floats from the valve seat surface 22a becomes the largest. Therefore, in order to prevent the valve member 30A from floating from the valve seat surface 22a in any of the cases 1 to 4, the valve member 30A is not lifted from the valve seat surface 22a in the case 1 which is the worst case. What should I do? That is, the force FS for pressing the valve member 30A by the coil spring 63 toward the valve seat surface 22a may be set so as to exceed at least 60 [N], which is a force for lifting the valve member 30A in the case 1.

When the flow path switching valve 1A described above has a uniform diameter in the axial direction without providing the small-diameter cylindrical portion 31a and the large-diameter cylindrical portion 31b in the cylindrical portion 31 as in the conventional configuration (that is, SH2 = SH1 = When the case 4 is in the state of 380 square millimeters), the force F1 acting on the valve member 30A by the fluid pressure in the sealed space G1 is:
F1 = (− ΔP2) × S2 = 756 [N] (3-9)
The force F2 acting on the valve member 30A by the fluid pressure in the back pressure chamber H is
F2 = ΔP2 × SH2 = −1140 [N] (3-10)
It becomes. Therefore, from the above formulas (23) and (24), the valve member 30A has
F = F1 + F2 = −384 [N]
In other words, a force of 384 [N] acts so as to lift the valve member 30A from the valve seat surface 22a. In this case, it is necessary to press the valve member 30A toward the valve seat surface 22a with a force exceeding at least 384 [N] by the coil spring 63, and this case 4 becomes the worst case. From this, in this embodiment, when the relationship between the fluid pressure in the back pressure chamber H and the fluid pressure in the valve chamber B is switched, the plan view area to which the fluid pressure in the back pressure chamber H in the valve member 30A is applied is changed. To do. Specifically, the plane view area SH2 when the fluid pressure in the valve chamber B is higher than the fluid pressure in the back pressure chamber H is the plane when the fluid pressure in the valve chamber B is lower than the fluid pressure in the back pressure chamber H. It becomes smaller than the viewing area SH1. Thereby, the force set to the coil spring 63 becomes small compared with the conventional structure.

As described above, in the flow path switching valve 1 A, when the fluid pressure in the sealed space G 1 and the back pressure chamber H is higher than the fluid pressure in the valve chamber B, the seal ring 38 is provided on the cylindrical portion 31 of the valve member 30 A. It is pressed against the cylindrical step surface 31c. Therefore, the fluid pressure in the back pressure chamber H is applied to the location of the large-diameter cylindrical portion 31b (that is, the planar view area SH1). Further, when the fluid pressure in the sealed space G 1 and the back pressure chamber H is lower than the fluid pressure in the valve chamber B, the seal ring 38 is pressed against the support portion step surface 15 c of the valve member support portion 15 of the valve body 10. . For this reason, the fluid pressure in the back pressure chamber H is applied to the small-diameter cylindrical portion 31a (that is, the planar view area SH2).

That is, the flow path switching valve 1A has a back pressure chamber having a plan view area SH2 to which the fluid pressure of the back pressure chamber H in the valve member 30A when the fluid pressure of the back pressure chamber H is lower than the fluid pressure of the valve chamber B is applied. It is configured to be smaller than the planar view area SH1 when the fluid pressure of H is higher than the fluid pressure of the valve chamber B. An annular seal ring 38 that seals between the valve body 10 and the valve member 30A is provided. When the fluid pressure in the back pressure chamber H is higher than the fluid pressure in the valve chamber B, the seal ring is provided. 38 is pressed against the valve member 30A, and the seal ring 38 is pressed against the valve body 10 when the fluid pressure in the back pressure chamber H is lower than the fluid pressure in the valve chamber B.

As described above, the flow path switching valve 1A of the present embodiment includes the valve body 10 provided with the space Q inside, the planar valve seat surface 22a facing the space Q, and the valve seat surface 22a. The valve seat portion 20A having the first fixed port E1, the second fixed port E2, the first switching port C1 and the second switching port C2 and the valve seat surface 22a are slidably rotated and arranged in the space Q. The valve member 30A for switching the communication relationship of the first fixed port E1, the second fixed port E2, the first switching port C1 and the second switching port C2 determined by the stop position by rotation, and the valve member 30A for the valve seat surface 22a And a coil spring 63 that is pressed toward the head. Further, the valve member 30A is connected to one end of the cylindrical portion 31 supported by the valve main body 10 so as to be rotatable around the axis, and forms a sealed space G1 between the valve seat surface 22a and the valve member 30A. A sealed communication passage 34A that connects the first fixed port E1, the second fixed port E2, the first switching port C1, and the second switching port C2 in a predetermined combination according to the stop position of the valve member 30A is provided by the sealed space G1. And a valve body portion 33A. The valve body 10 is formed on a valve chamber B in which a valve body portion 33A formed on one end side of the cylindrical portion 31 is accommodated by partitioning the space Q by the valve member 30A, and on the other end side of the cylindrical portion 31. A back pressure chamber H. The valve member 30 A has a pressure equalizing path 36 that connects the sealed communication path 34 A and the back pressure chamber H. The cylindrical portion 31 includes a small-diameter cylindrical portion 31a arranged so that one end surface faces the back pressure chamber H, a large-diameter cylindrical portion 31b coaxially connected to the other end surface of the small-diameter cylindrical portion 31a, and a small-diameter cylindrical portion 31a. A cylindrical stepped surface 31c formed between the outer peripheral surface 31a1 and the outer peripheral surface 31b1 of the large-diameter cylindrical portion 31b. The valve body 10 includes a small-diameter hole portion 15a into which the small-diameter cylindrical portion 31a is rotatably fitted, a large-diameter hole portion 15b into which the large-diameter cylindrical portion 31b is rotatably fitted, and an inner circumference of the small-diameter hole portion 15a. The valve member support portion 15 is provided with a support stepped surface 15c formed between the surface 15a1 and the inner peripheral surface 15b1 of the large-diameter hole portion 15b. The outer peripheral surface of the small-diameter cylindrical portion 31a is placed in the seal space R surrounded by the outer peripheral surface 31a1, the cylindrical stepped surface 31c, the inner peripheral surface 15b1 of the large-diameter hole 15b, and the support stepped surface 15c. An annular seal ring 38 is provided for sealing between 31a1 and the inner peripheral surface 15b1 of the large-diameter hole 15b.

As described above, according to the present embodiment, the cylindrical portion 31 supported by the valve body 10 so as to be rotatable about the axis is a small-diameter cylindrical portion 31a disposed so that one end surface faces the back pressure chamber H, A large-diameter cylindrical portion 31b coaxially connected to the other end surface of the small-diameter cylindrical portion 31a, a cylindrical step surface 31c formed between the outer peripheral surface 31a1 of the small-diameter cylindrical portion 31a and the outer peripheral surface 31b1 of the large-diameter cylindrical portion 31b; have. The valve body 10 includes a small-diameter hole portion 15a in which the small-diameter cylindrical portion 31a of the cylindrical portion 31 is rotatably fitted, and a large-diameter hole portion in which the large-diameter cylindrical portion 31b of the cylindrical portion 31 is rotatably fitted. 15b, and a valve member support portion 15 provided with a support stepped surface 15c formed between the inner peripheral surface 15a1 of the small diameter hole portion 15a and the inner peripheral surface 15b1 of the large diameter hole portion 15b. Yes. The cylindrical portion 31 is surrounded by the outer peripheral surface 31a1 of the small-diameter cylindrical portion 31a, the cylindrical stepped surface 31c, the inner peripheral surface 15b1 of the large-diameter hole portion 15b of the valve member supporting portion 15 of the valve body 10, and the supporting portion stepped surface 15c. In the sealed space R, an annular seal ring 38 is provided for sealing between the outer peripheral surface 31a1 of the small diameter cylindrical portion 31a and the inner peripheral surface 15b1 of the large diameter hole portion 15b. As a result, the fluid pressure in the valve chamber B is applied to a portion of the seal ring 38 on the columnar step surface 31c side, and a back pressure chamber is applied to the portion of the seal ring 38 on the support step surface 15c side. Fluid pressure in H is applied. Therefore, when the fluid pressure in the back pressure chamber H is higher than the fluid pressure in the valve chamber B, the seal ring 38 is pressed against the cylindrical step surface 31c by the fluid pressure in the back pressure chamber H, and the valve member 30A is flat. The fluid pressure in the back pressure chamber H is applied to a location inside the outer diameter of the large-diameter cylindrical portion 31b as viewed. Further, when the fluid pressure in the back pressure chamber H is lower than the fluid pressure in the valve chamber B, the seal ring 38 is pressed against the support step surface 15c by the fluid pressure in the valve chamber B, and the valve member 30A is viewed in plan view. Thus, the fluid pressure in the back pressure chamber H is applied to a location inside the outer diameter of the small diameter cylindrical portion 31a. That is, when the fluid pressure in the back pressure chamber H is lower than the fluid pressure in the valve chamber B, the force that causes the valve member 30A to lift from the valve seat surface 22a is exerted by the fluid pressure in the back pressure chamber H. However, since the area of the portion of the valve member 30A where the fluid pressure in the back pressure chamber H is applied is reduced, the force to lift the valve member 30A from the valve seat surface 22a can be reduced. Thereby, since the force which presses the valve member 30A by the coil spring 63 toward the valve seat surface 22a can be made small, the force which presses the valve member 30A to the valve seat surface 22a can be suppressed.

Further, the flow path switching valve 1A has a back pressure chamber having a plan view area SH2 to which the fluid pressure of the back pressure chamber H in the valve member 30A when the fluid pressure of the back pressure chamber H is lower than the fluid pressure of the valve chamber B is applied. The fluid pressure of H is configured to be smaller than the planar view area SH1 when the fluid pressure of the valve chamber B is higher than the fluid pressure of the valve chamber B. Thus, when the fluid pressure in the back pressure chamber H is lower than the fluid pressure in the valve chamber B, the fluid pressure in the back pressure chamber H causes the valve member 30A to rise from the valve seat surface 22a. When the force is working, the area of the valve member 30A where the fluid pressure in the back pressure chamber H is applied (that is, the area in plan view) is reduced, so that the force that lifts the valve member 30A from the valve seat surface 22a Can be small. Thereby, since the force which presses the valve member 30A by the coil spring 63 toward the valve seat surface 22a can be made small, the force which presses the valve member 30A to the valve seat surface 22a can be suppressed.

Further, in the flow path switching valve 1A, an annular seal ring 38 is provided between the valve main body 10 and the valve member 30A to seal between them. When the fluid pressure in the back pressure chamber H is higher than the fluid pressure in the valve chamber B, the seal ring 38 is pressed against the valve member 30A. When the fluid pressure in the back pressure chamber H is lower than the fluid pressure in the valve chamber B, the seal ring 38 is sealed. The ring 38 is configured to be pressed against the valve body 10. As a result, the annular seal ring 38 that seals between the valve body 10 and the valve member 30A has a fluid pressure in the back pressure chamber H on a part of the surface (a portion on the support step surface 15c side). Is added, and the fluid pressure in the valve chamber B is applied to the other part of the surface (location on the cylindrical stepped surface 31c side). When the seal ring 38 is pressed against the valve member 30A when the fluid pressure in the back pressure chamber H is higher than the fluid pressure in the valve chamber B, the back pressure applied to the planar view area of a part of the surface of the seal ring 38 is increased. The fluid pressure in the chamber H is also applied to the valve member 30A. Further, when the seal ring 38 is pressed against the valve body 10 when the fluid pressure in the back pressure chamber H is lower than the fluid pressure in the valve chamber B, the valve chamber B applied to the other part of the surface of the seal ring 38 Fluid pressure is also applied to the valve body 10. That is, when the fluid pressure in the back pressure chamber H is lower than the fluid pressure in the valve chamber B, the planar view area SH2 to which the fluid pressure in the back pressure chamber H in the valve member 30A is applied (that is, directly or indirectly through the seal member). The planar view area to be applied) is configured to be smaller than the planar view area SH1 when the fluid pressure in the back pressure chamber H is higher than the fluid pressure in the valve chamber B. Therefore, when the fluid pressure in the back pressure chamber H is lower than the fluid pressure in the valve chamber B, the force that lifts the valve member 30A from the valve seat surface 22a by the fluid pressure in the back pressure chamber H works. However, since the area of the valve member 30A where the fluid pressure in the back pressure chamber H is applied (that is, the plan view area) is reduced, the force to lift the valve member 30A from the valve seat surface 22a is reduced. Can do. Thereby, since the force which presses the valve member 30A by the coil spring 63 toward the valve seat surface 22a can be made small, the force which presses the valve member 30A to the valve seat surface 22a can be suppressed.

As mentioned above, although this invention was demonstrated and mentioned with preferable embodiment, the rotary type valve apparatus of this invention is not limited to the structure of the said embodiment.

For example, although the said 1st Embodiment was the structure by which the sealing recessed part 34 was provided in the lower end surface 33a of the valve body part 33 of the valve member 30, it is not limited to this, The lower end surface 33a is planar. It is good also as a structure which abbreviate | omitted the sealing recessed part 34 as a shape. In this configuration, when the lower end surface 33a overlaps the first valve port P1 or the second valve port P2, one end of the pressure equalizing path 36 is connected so that these valve ports and the back pressure chamber H are connected to each other. It arrange | positions at the lower end surface 33a.

Moreover, although the said 2nd Embodiment was a flow-path switching valve (four-way switching valve) which switches four flow paths, it is not limited to this, For example, the structure which switches three flow paths, A flow path switching valve configured to switch between five or more flow paths may be used. Moreover, you may apply this invention to the valve apparatus which connects and interrupts | blocks two flow paths.

In the second embodiment, the configuration has one sealed communication path. However, the present invention is not limited to this, and a configuration having two or more sealed communication paths may be used. For example, in the above embodiment, the connection hole 33b of the valve member 30 may be omitted and the open communication path 35 may be configured as a sealed communication path.

In the second embodiment, the valve body portion 33A of the valve member 30 is provided with the sealed communication path 34A and the open communication path 35. However, the present invention is not limited to this. For example, It is good also as a structure which provided only the sealing communication path 34A in the valve body part 33A, and deleted the location which forms the open communication path 35. FIG. Even in such a configuration in which the open communication path 35 is omitted, at each stop position of the valve member 30A, the second fixed port E2, the first switching port C1, and the first fixed port E1 of the second switching port C2 are connected. One that is not in communication is exposed to the inner space 11a, which is another part of the valve chamber B, and these ports are connected and connected, so that the communication relationship of the valve ports can be switched.

Moreover, in each said embodiment, although it was the structure which provided the pressure equalization path 36 in the valve member 30 and the valve member 30A, it is not limited to this, As a structure which provided the pressure equalization path in the valve main body 10 Also good.

In each of the above embodiments, the first seal ring 61 and the second seal ring 62 are made of a relatively soft elastic material. However, the present invention is not limited to this. For example, the second seal ring 62 disposed closer to the outside of the valve body 10 than the first seal ring 61 may be made of a relatively hard synthetic resin such as a fluororesin such as polytetrafluoroethylene (PTFE). As long as the object of the present invention is not violated, the configurations of the first seal ring 61 and the second seal ring 62 are arbitrary. In addition, the second seal ring 62 may be omitted as long as the sealing performance can be sufficiently secured only by the first seal ring 61.

It should be noted that the above-described embodiments are merely representative forms of the present invention, and the present invention is not limited to the embodiments. That is, those skilled in the art can implement various modifications in accordance with conventionally known knowledge without departing from the scope of the present invention. As long as the configuration of the rotary valve device of the present invention is provided even by such modification, it is, of course, included in the category of the present invention.

1 Two-way valve (rotary valve device)
1A Channel switching valve (rotary valve device)
DESCRIPTION OF SYMBOLS 10 Valve main body 15 Valve member support part 15a Small diameter hole part 15a1 Inner peripheral surface 15b Large diameter hole part 15b1 Inner peripheral surface of large diameter hole part 15c Support part level |

step difference surface

20, 20A Valve seat part 22a

Valve seat surface

30 , 30A Valve member 31 Column part (shaft part)
31a Small diameter cylindrical part (small diameter shaft part)
31a1 Outer peripheral surface of small diameter cylindrical portion 31b Large diameter cylindrical portion (large diameter shaft portion)
31b1 Outer peripheral surface of large-diameter cylindrical portion 31c Columnar step surface (shaft step surface)
31d Upper end surface of cylindrical portion 32 Rotating shaft

portion mounting hole

33, 33A Valve body portion 33a Lower end surface of valve body portion 33a1 Outer peripheral edge of lower end surface 33a2 Inner peripheral edge of lower end surface 33a3 Outer peripheral edge of portion surrounding sealed communication path on lower end surface 33a4 Inner peripheral edge of the portion surrounding the sealed communication path on the lower end surface 34 Sealed recess 34A Sealed communication path 36 Pressure equalizing path 38 Seal ring (seal member)
40 Rotating shaft portion 50 Rotation driving portion 63 Coil spring (pressing member)
B Valve chamber C1 First switching port (valve port)
C2 Second switching port (valve port)
F1 First fixed port (valve port)
F2 Second fixed port (valve port)
G, G1 Sealed space H Back pressure chamber P1 First valve port P2 Second valve port Q Space inside valve body R Seal space (outer peripheral surface of small diameter shaft portion, stepped surface of shaft portion, inner peripheral surface of large diameter hole portion) And the space surrounded by the step surface of the support part)
L Shaft of circular through hole

Claims

A valve body having a space provided inside, a valve seat surface having a planar valve seat surface facing the space, and two valve ports opening to the valve seat surface, and slidingly rotatable on the valve seat surface A valve member that is arranged in the space and is switched in accordance with a stop position, and that switches the communication relationship between the two valve ports by rotation, and a pressing member that presses the valve member toward the valve seat surface. Rotary valve device
The valve member is provided at one end of the shaft portion that is supported by the valve body so as to be rotatable about an axis, and at least one valve of the two valve ports according to the stop position A valve body for opening and closing the port,
The valve body is formed on one end side of the shaft portion by partitioning the space by the valve member, and is formed on the other end side of the shaft portion. A back pressure chamber,
The valve body or the valve member has a pressure equalizing path that connects the back pressure chamber and the valve port that is opened and closed by the valve body portion of the two valve ports,
When the fluid pressure in the back pressure chamber is lower than the fluid pressure in the valve chamber, the planar view area where the fluid pressure in the back pressure chamber is applied to the valve member is the fluid pressure in the valve chamber. It is comprised so that it may become smaller than the said planar view area when higher than a pressure, The rotary type valve apparatus characterized by the above-mentioned.
A valve body provided with a space inside, a valve seat surface having a planar valve seat surface facing the space and a plurality of valve ports opening to the valve seat surface, and slidingly rotatable on the valve seat surface A valve member that is disposed in the space and that switches the communication relationship of the plurality of valve ports determined by the stop position by rotation, and a pressing member that presses the valve member toward the valve seat surface. Rotary valve device
The valve member is provided at one end of the shaft portion that is rotatably supported about the shaft center by the valve body, and forms a sealed space between the valve seat surface and the sealed space. A valve body portion provided with one or a plurality of sealed communication passages that communicate the plurality of valve ports in a predetermined combination according to the stop position;
The valve body is formed on one end side of the shaft portion by partitioning the space by the valve member, and is formed on the other end side of the shaft portion. A back pressure chamber,
The valve body or the valve member has a pressure equalizing path connecting any one of the sealed communication passages and the back pressure chamber;
When the fluid pressure in the back pressure chamber is lower than the fluid pressure in the valve chamber, the planar view area where the fluid pressure in the back pressure chamber is applied to the valve member is the fluid pressure in the valve chamber. It is comprised so that it may become smaller than the said planar view area when higher than a pressure, The rotary type valve apparatus characterized by the above-mentioned.
Between the valve body and the valve member, an annular seal member is provided for sealing between them,
The seal member is pressed against the valve member when the fluid pressure in the back pressure chamber is higher than the fluid pressure in the valve chamber, and the seal member when the fluid pressure in the back pressure chamber is lower than the fluid pressure in the valve chamber. The rotary valve device according to claim 1, wherein the rotary valve device is configured to be pressed against the valve body.
The shaft portion of the valve member has a small-diameter shaft portion arranged so that one end surface thereof faces the back pressure chamber, a large-diameter shaft portion coaxially connected to the other end surface of the small-diameter shaft portion, and the small-diameter shaft portion A shaft stepped surface formed between the outer peripheral surface of and the outer peripheral surface of the large-diameter shaft portion,
The valve body includes a small diameter hole portion in which the small diameter shaft portion is rotatably fitted, a large diameter hole portion in which the large diameter shaft portion is rotatably fitted, an inner peripheral surface of the small diameter hole portion, and A support member step surface formed between the inner peripheral surface of the large-diameter hole portion, and a valve member support portion provided with,
The seal member has an outer peripheral surface of the small diameter shaft portion, an outer peripheral surface of the small diameter shaft portion, a space surrounded by the stepped surface of the shaft portion, an inner peripheral surface of the large diameter hole portion, and a step surface of the support portion. The rotary valve device according to claim 3, wherein the rotary valve device is provided so as to seal between the inner peripheral surface of the large-diameter hole portion.
A valve body having a space provided inside, a valve seat surface having a planar valve seat surface facing the space, and two valve ports opening to the valve seat surface, and slidingly rotatable on the valve seat surface A valve member that is arranged in the space and is switched in accordance with a stop position, and that switches the communication relationship between the two valve ports by rotation, and a pressing member that presses the valve member toward the valve seat surface. Rotary valve device
The valve member is connected to the valve main body so as to be rotatable about an axis, and is connected to one end of the cylindrical portion, and at least one valve port of the two valve ports according to the stop position A valve body part for opening and closing,
The valve body is formed on one end side of the columnar portion, the valve chamber accommodating the valve body portion, and formed on the other end side of the columnar portion by dividing the space by the valve member. A back pressure chamber,
The valve body or the valve member has a pressure equalizing path that connects the back pressure chamber and the valve port that is opened and closed by the valve body portion of the two valve ports,
The cylindrical portion is a small-diameter cylindrical portion disposed so that one end surface faces the back pressure chamber, a large-diameter cylindrical portion coaxially connected to the other end surface of the small-diameter cylindrical portion, an outer peripheral surface of the small-diameter cylindrical portion, and A cylindrical step surface formed between the outer peripheral surfaces of the large-diameter cylindrical portion,
The valve body includes a small diameter hole portion in which the small diameter cylindrical portion is rotatably fitted, a large diameter hole portion in which the large diameter cylindrical portion is rotatably fitted, an inner peripheral surface of the small diameter hole portion, and A support member step surface formed between the inner peripheral surface of the large-diameter hole portion, and a valve member support portion provided with,
In the space surrounded by the outer peripheral surface of the small diameter cylindrical part, the stepped surface of the cylindrical part, the inner peripheral surface of the large diameter hole part and the stepped surface of the support part, the outer peripheral surface of the small diameter cylindrical part and the large diameter hole part An annular seal member is provided for sealing between the inner peripheral surface of the rotary valve device.
A valve body provided with a space inside, a valve seat surface having a planar valve seat surface facing the space and a plurality of valve ports opening to the valve seat surface, and slidingly rotatable on the valve seat surface A valve member that is disposed in the space and that switches the communication relationship of the plurality of valve ports determined by the stop position by rotation, and a pressing member that presses the valve member toward the valve seat surface. Rotary valve device
The valve member is connected to the cylinder body rotatably supported by the valve body about an axis, and is connected to one end of the cylinder part to form a sealed space between the valve seat surface and the sealed space. A valve body portion provided with one or a plurality of sealed communication passages that communicate the plurality of valve ports in a predetermined combination according to a stop position;
The valve body is formed on one end side of the columnar portion, the valve chamber accommodating the valve body portion, and formed on the other end side of the columnar portion by dividing the space by the valve member. A back pressure chamber,
The valve body or the valve member has a pressure equalizing path connecting any one of the sealed communication passages and the back pressure chamber;
The cylindrical portion is a small-diameter cylindrical portion disposed so that one end surface faces the back pressure chamber, a large-diameter cylindrical portion coaxially connected to the other end surface of the small-diameter cylindrical portion, an outer peripheral surface of the small-diameter cylindrical portion, and A cylindrical step surface formed between the outer peripheral surfaces of the large-diameter cylindrical portion,
The valve body includes a small diameter hole portion in which the small diameter cylindrical portion is rotatably fitted, a large diameter hole portion in which the large diameter cylindrical portion is rotatably fitted, an inner peripheral surface of the small diameter hole portion, and A support member step surface formed between the inner peripheral surface of the large-diameter hole portion, and a valve member support portion provided with,
In the space surrounded by the outer peripheral surface of the small diameter cylindrical part, the stepped surface of the cylindrical part, the inner peripheral surface of the large diameter hole part and the stepped surface of the support part, the outer peripheral surface of the small diameter cylindrical part and the large diameter hole part An annular seal member is provided for sealing between the inner peripheral surface of the rotary valve device.