Flow path switching valve

Abstract

To provide a flow passage switching valve for setting management points of a member dimension tolerance to a minimum number, and making a valve body rotatable at small torque.SOLUTION: A flow passage switching valve 10 comprises: a valve main body 14 in which a valve chamber 12 is formed; a valve body 16 which is arranged in the valve chamber 12; an annular seat member 38 which is arranged between entrances 24, 26 of the valve main body 14 and the valve body 16, and in which a side face on an opposite side to the valve body side contacts with a wall face of the valve main body 14, and an external peripheral face is separated from the valve main body 14; an inclination seal face 38A which is formed at the seat member 38 and is inclined to an axial line by a constant angle θ, and with which an external peripheral face of the valve body 16 contacts; O-rings 50 which are compressively accommodated in O-ring grooves 48, 60 provided on the wall face of the valve main body 14; and a rotation drive part 18 which rotates the valve body 16. A value of the angle θ is determined so that a pressing force between the valve body 16 and the seat member 38 at the lowest temperature in a use state and a pressing force between the valve body 16 and the seat member 38 at the highest temperature in the use state do not differ from each other.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a flow path switching valve, and more particularly to a flow path switching valve that switches a flow path by rotating and sliding a ball-shaped valve element within a valve chamber. [Background technology]

[0002] 2. Description of the Related Art A flow path switching valve of a type that switches flow paths by the rotational movement of a ball-shaped valve element is known (see, for example, Patent Document 1).

[0003] In this type of flow path switching valve, the valve body is rotationally driven by a rotary drive unit including a motor, a drive gear, and the like. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2018-115691 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the flow path switching valve of Patent Document 1, a pair of annular seat members are arranged in a valve chamber corresponding to a pair of outlet ports facing each other, and a ball-shaped valve body is arranged between the pair of seat members so as to be freely rotatable and slidable. An annular groove is formed on the side surface of this seat member opposite the valve body side, and an O-ring made of an elastic material such as rubber is disposed in a compressed state in this annular groove. The side of the seat member opposite the valve disc is spaced from the wall of the valve chamber, and its outer circumferential surface is in close contact with the inner circumferential surface of the valve chamber. The seat member arranged inside the valve chamber is pressed against the outer circumferential surface of the valve disc by the elastic force (repulsive force) of the O-ring, thereby hermetically sealing the gap between the valve disc and each outlet port.

[0006] The valve body is sandwiched between a pair of annular seat members, and the pair of seat members are pressed against each other by the elastic force of the O-ring, so a rotational force (torque) is required to rotate the valve body.

[0007] A flow path switching valve needs to be designed to guarantee the specified leakage amount. To guarantee the specified leakage amount, the maximum compression rate is calculated from the minimum compression rate of the O-ring, taking into account the dimensional tolerances of each part, the effects of temperature, and deterioration over time. The torque that rotates the valve body when the O-ring reaches its maximum compression rate is the maximum torque. For this reason, the specifications of the rotary drive unit are determined so as to generate a torque higher than the above-mentioned maximum torque.

[0008] Incidentally, when the outer peripheral surface of the seat member is in contact with and restrained by the inner peripheral surface of the valve chamber, and the side surface of the seat member opposite the valve disc is in contact with the wall surface of the valve chamber opposing said side surface, the seat member and the wall surface of the valve chamber are in contact to prevent fluid leakage at room temperature. Even if the seat member and the valve disc are in contact, clearance and fastening will occur due to the difference in linear expansion between low and high temperatures.

[0009] That is, when the seat member becomes hot, the seat member expands in the axial direction and is pressed strongly against the valve body, and the valve body is tightly clamped between the pair of seat members, making it difficult to rotate the valve body. On the other hand, when the temperature of the seat member becomes low, the seat member shrinks, and it is considered that a clearance (gap) occurs between the seat member and the valve body, and between the side surface of the seat member and the wall surface of the valve chamber.

[0010] For this reason, by bringing the outer peripheral surface of the seat member into contact with the inner peripheral surface of the valve chamber, providing a gap between the side of the seat member opposite the valve body and the wall surface of the valve chamber facing this wall, and placing an O-ring, which is an elastic body, between the seat member and the wall surface of the valve chamber, it becomes possible for this gap to absorb axial dimensional changes of the seat member caused by temperature changes.

[0011] However, in order to rotate the valve disc with a small torque, a pair of seat members, a valve disc, and a pair of O-rings are arranged in series inside the valve chamber, and it is necessary to control many dimensions such as the thickness of the seat members, the diameter of the valve disc, the wire diameter of the O-ring, the groove depth of the O-ring groove in which the O-ring is arranged, and the width of the valve chamber that houses them. This makes dimensional control complicated, and since the compression rate of the O-ring varies greatly due to the dimensional tolerances of each component, a high-torque drive part is required to rotate the valve, which may result in a large size.

[0012] SUMMARY OF THE PRESENT INVETION The present invention has been made in consideration of the above circumstances, and has an object to provide a flow passage switching valve in which the number of parts requiring dimensional control is minimized and the valve body can be rotated with a small torque. [Means for solving the problem]

[0013] The inventors conducted various studies and experiments on a flow path switching valve equipped with a ball-shaped valve body, and found that by setting the relationship between the components and the angle θ of the inclined seal surface of the seat member with which the outer peripheral surface of the valve body comes into contact to a certain value, it becomes easy to manage the dimensions of the components in order to reduce the torque that rotates the valve body, and the torque that rotates the valve body becomes less susceptible to the effects of temperature.

[0014] The present invention has been made in view of the above facts, and a flow path switching valve according to claim 1 comprises a valve body having a valve chamber formed therein and an inlet / outlet opening in at least a pair of opposing wall surfaces of the valve chamber; a ball-shaped valve body rotatably disposed within the valve chamber and having a flow path formed therein; an annular seat member disposed between the valve body and the inlet / outlet to seal the space between the valve body and the inlet / outlet, the side surface opposite to the valve body contacting the wall surface and the outer circumferential surface being spaced from the valve body; and an annular seat member formed at the opening end of the seat member on the valve body side, which is inclined at a certain angle θ with respect to the axis when viewed in a cross section taken along the axis of the seat member, and the outer circumferential surface of the valve body contacting the wall surface. a retaining groove provided on either the side of the seat member facing the valve body or the wall surface of the valve body and recessed in the direction of the axis of the seat member; an elastic body that is accommodated in the retaining groove and is compressed with the side of the seat member in contact with the wall surface, thereby pressing the seat member against the valve body; and a rotation drive unit that rotates the valve body so that the communication state of the multiple inlets and outlets is selectively switched through the flow paths of the valve body, and the value of the angle θ is determined so that the pressing force between the valve body and the seat member at the lowest temperature in use does not change from the pressing force between the valve body and the seat member at the highest temperature in use.

[0015] In the flow path switching valve according to claim 1, the valve body can be rotated using the rotational force (torque) of the rotary drive portion.

[0016] In the flow path switching valve according to claim 1, the valve body, a pair of seat members, and a pair of elastic bodies are arranged in series inside the valve chamber. The inclined seal surface of the seat member contacts the valve body, and the side opposite to the valve body contacts the wall surface of the valve chamber.

[0017] The elastic body that presses the seat member against the valve body is in a compressed state in a recess provided in either the side surface of the seat member facing the valve body or the wall surface of the valve body. Therefore, in order to determine the elastic force of the elastic body that presses the seat member against the valve body, it is sufficient to determine the compression rate of the elastic body by controlling two dimensions, the depth of the recess and the size of the elastic body.

[0018] When the temperature of the sheet member rises and the axial thickness of the sheet member increases, the pressing force of the sheet member pressing the valve body in the axial direction increases. In the flow path switching valve according to claim 1, since the outer peripheral portion of the sheet member and the inner peripheral portion of the valve chamber are separated from each other and a gap is provided therebetween, the radial expansion of the sheet member is not hindered. For this reason, when the temperature of the sheet member rises, the diameter of the sheet member increases, and the inclined seal surface moves away from the valve body in the radial direction of the sheet member, resulting in a decrease in the pressing force for pressing the valve body.

[0019] That is, not only the dimension in the thickness direction (axial direction) of the sheet member but also the dimension in the radial direction of the sheet member is related to the pressing force of the sheet member on the valve body. Therefore, when the angle θ of the inclined seal surface that contacts the valve body is set to an appropriate angle, the force pressing the valve body due to the expansion of the sheet member can be made not to change even when a temperature change occurs.

[0020] In the flow path switching valve according to claim 1, since the angle θ of the inclined seal surface is set so that the force pressing the valve body due to the expansion of the sheet member does not change even when a temperature change occurs, the torque required when rotationally driving the valve body is less likely to be affected by temperature.

[0021] The invention according to claim 2 is the flow path switching valve according to claim 1, wherein an annular recess in which the sheet member is disposed is provided on the wall surface of the valve body, a side portion of the sheet member is always in contact with a bottom portion of the annular recess, and the holding groove is provided at the bottom portion of the annular recess and the elastic body is fitted therein.

[0022] The invention according to claim 3 is the flow path switching valve according to claim 1 or claim 2, wherein the angle θ is 57.9 ± 5.79°.

Advantages of the Invention

[0023] As described above, according to the flow path switching valve of the present invention, it is possible to minimize the number of parts requiring dimensional control and to rotate the valve body with a small torque. [Brief description of the drawings]

[0024] [Figure 1] 1 is a perspective view showing a flow path switching valve according to an embodiment of the present invention; [Diagram 2] 2 is a cross-sectional view of the flow path switching valve taken along line 2-2 of FIG. 1. [Diagram 3] FIG. 2 is an enlarged cross-sectional view showing a main part of a flow path switching valve. [Figure 4] FIG. 4 is a cross-sectional view of the valve body showing the flow paths of the valve body. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] A flow path switching valve 10 according to one embodiment of the present invention will be described with reference to FIGS. 1 to 4. FIG. In each drawing, the gaps between components, the distances between components, etc. may be exaggerated to facilitate understanding of the invention and for convenience in drawing. In addition, in this specification, descriptions indicating positions and directions such as up / down, left / right, front / back, etc. are based on the directional arrows in Figures 1 and 2, and do not indicate positions and directions in actual use.

[0026] (Configuration of flow path switching valve) FIG. 1 is a perspective view showing the overall configuration of a flow path switching valve 10 according to one embodiment of the present invention, and FIG. 2 is a vertical cross-sectional view (cross-sectional view taken along line 2-2) of the flow path switching valve 10 shown in FIG.

[0027] The flow path switching valve 10 of the embodiment shown in FIG. 1 is used as a rotary three-way valve for switching the flow path of a fluid flowing, for example, in an engine room of an automobile between multiple directions, and basically includes a valve body 14 having a valve chamber 12, a ball-shaped valve element (also referred to as a ball valve element) 16 rotatably disposed within the valve chamber 12, and a rotation drive unit 18 consisting of a motor, drive gears, etc., disposed from the rear to the upper part of the valve body 14 in order to rotate the valve element 16 around a rotation axis (center line) O1, as shown in FIG. The rotation axis O1 (axis extending in the vertical direction) of the valve element 16 housed in the valve chamber 12 is coaxial with the center line of a valve shaft 18A of the rotation drive unit 18, which will be described later.

[0028] (Valve body, valve chamber) The valve body 14 includes a base member 20 and a port member 44, each of which is made of a synthetic resin, for example.

[0029] 2 and 3, the base member 20 has a cylindrical valve chamber 12 formed therein, the valve chamber 12 being laid on its side. An annular recess 46 is formed in a right-side first wall surface 12R on the right side of the arrow (right side in the drawing) of the valve chamber 12. A horizontal outlet (inlet / outlet) 26 that opens into the valve chamber 12 is formed in the center of the bottom of the annular recess 46, and an O-ring groove 48 (retaining groove) is formed on the radial outside of the outlet 26. An O-ring 50 that serves as both an elastic body and a sealing member is fitted into the O-ring groove 48.

[0030] As shown in FIGS. 1 and 2, an L-shaped port 26A made of a pipe joint is integrally provided on the outer surface of the base member 20 on the right side of the arrow so as to communicate with the outlet port 26.

[0031] (Port parts) As shown in FIG. 2, the valve chamber 12 is open on the left side of the arrow (the left side of the figure), and an L-shaped port member 44 connected to the valve chamber 12 is fixed to the end of the valve body 14 on the left side of the arrow. The port member 44 has an L-shaped port 52 serving as a pipe joint, and on the valve chamber 12 side of the port 52, there are formed an annular flange 54 that abuts against the end face of the valve body 14, and a cylindrical insertion portion 56 that is inserted into the valve chamber 12. A lateral outflow port (inflow / outlet) 24 that opens into the valve chamber 12 is provided on the end of the insertion portion 56 on the valve chamber 12 side.

[0032] The port member 44 is fixed to the valve body 14 by welding with the insertion portion 56 inserted into the valve chamber 12 and the flange 54 abutting against the end face of the valve body 14 .

[0033] 3, an annular recess 58 in which a sheet member 38 (described later) is disposed is formed at the tip portion of the insertion portion 56, and an O-ring groove 60 (retaining groove) similar to the O-ring groove 48 is formed at the bottom of the annular recess 58. An O-ring 50 is fitted inside the O-ring groove 60, similar to the O-ring groove 48.

[0034] 1, the valve body 14 is provided with a lateral inlet (inlet / outlet, not shown) that opens into the valve chamber 12, on the wall surface on the forward side of the valve chamber 12 as indicated by the arrow in the drawing. A port 28A made of a pipe fitting is integrally provided on the outer surface of the valve body 14 so as to communicate with the inlet (inlet / outlet).

[0035] 2 and 3, an insertion hole 30 through which the valve shaft 18A of the rotary drive unit 18 is rotatably inserted is provided in the upper part of the valve body 14. An O-ring groove 32 is formed on the outer periphery of the axially middle part of the valve shaft 18A, and an O-ring 34 serving as a sealing member is fitted into the O-ring groove 32.

[0036] (Rotation drive unit) A valve shaft 18A of the rotary drive unit 18 is connected to the valve element 16, so that the valve shaft 18A and the valve element 16 rotate together.

[0037] (Valve body) The valve body 16 is made of, for example, synthetic resin. In order to selectively communicate an inlet 28 (not shown in Figs. 2 and 3) provided in the valve body 14 with the two outlets 24, 26, in other words, to selectively switch the communication state between the inlet 28 and the two outlets 24, 26, a flow path (internal flow path) 36 is provided inside the valve body 16 as shown in Fig. 4.

[0038] In detail, the valve body 16 has a through hole 36A penetrating in a first direction perpendicular to the direction of the rotation axis O1 of the valve body 16, and a horizontal hole 36B which merges from the outer periphery (side) of the valve body 16 into the center of the through hole 36A is formed in a direction perpendicular to the rotation axis O1 of the valve body 16 and perpendicular to the through hole 36A.

[0039] (Sheet material) As shown in FIG. 3, annular recesses 46, 58 formed around the outlets 24, 26 in the valve body 1 each include annular seat members 38 made of synthetic resin and having openings corresponding to the outlets 24, 26.

[0040] In other words, within the valve chamber 12 of the valve body 14, a pair of seat members 38, 38 are arranged so as to face each other on opposite sides of the rotation axis O1 of the valve body 16 in correspondence with the pair of left and right outlets 24, 26, and the valve body 16 is arranged between (inside) the pair of seat members 38, 38 so as to be freely rotatable and slidable.

[0041] The seat member 38 has an inclined seal surface 38A formed at the open end on the valve body 16 side, which is inclined at a certain angle θ° with respect to the axis O2 when viewed in a cross section along the axis O2 of the seat member 38, and which comes into annular and linear contact with the outer circumferential surface of the valve body 16. In other words, the inclined seal surface 38A is formed of a part of a concave conical surface.

[0042] Here, the seat member 38 on the right side of the arrow (right side in the drawing) has a flat base end surface 38b, which is the side surface opposite to the inclined seal surface 38A, constantly in contact with a bottom 46a of an annular recess 46 provided in the valve chamber 12, compressing the O-ring 50 by a predetermined amount. In addition, the outer diameter of the seat member 38 on the right side of the arrow (right side in the drawing) is slightly smaller than the inner diameter of the annular recess 46, and a gap is provided between the outer peripheral surface of the seat member 38 and the inner peripheral surface of the annular recess 46.

[0043] Furthermore, the seat member 38 on the left side of the arrow (left side in the drawing) has a flat base end surface 38b, which is the side surface opposite to the inclined seal surface 38A, constantly in contact with a bottom 58a of an annular recess 58 provided in the insertion portion 56 of the port member 44, thereby compressing the O-ring 50 by a predetermined amount. The outer diameter of the seat member 38 on the left side of the arrow (left side in the drawing) is slightly smaller than the inner diameter of the annular recess 58, and a gap is provided between the outer peripheral surface of the seat member 38 and the inner peripheral surface of the annular recess 58.

[0044] The elastic force (repulsive force) of the O-ring 50 compressed to a predetermined amount presses the inclined seal surface 38A of each seat member 38 into close contact with the valve body 16 (its outer peripheral seal surface), thereby hermetically sealing the gap between the valve body 16 and each outlet port 24, 26.

[0045] The groove depth of O-ring groove 48, the groove depth of O-ring groove 60, and the wire diameter of O-ring 50 are determined so that a predetermined elastic force of O-ring 50 (the force with which compressed O-ring 50 returns to its original shape) acts on valve body 16 via seat member 38. By setting the elastic force of O-ring 50 to a preset value, the rotational torque of valve body 16 can be determined.

[0046] As shown in FIG. 4, in this embodiment, the diameter of the opening side of the inclined seal surface 38A is a (mm), the thickness dimension from the surface of the seat member 38 with which the O-ring 50 contacts (the bottom surface of the O-ring groove 40) to the side surface of the seat member 38 on the valve body side is b (mm), the diameter of the valve body 16 is d (mm), and the distance between the bottom of the annular recess 58 on the left side of the arrow in the figure (left side in the figure) and the bottom of the annular recess 46 on the right side of the arrow in the figure (right side in the figure) that face each other in the valve chamber 12 is e (mm).

[0047] In the flow path switching valve 10 of this embodiment, the value of the angle θ is determined so that the pressing force between the valve body 16 and the seat member 38 at the lowest temperature in the usage state and the pressing force between the valve body 16 and the seat member 38 at the highest temperature in the usage state do not change.

[0048] Specifically, by taking into consideration the linear expansion coefficient of each component and optimizing the values ​​of a, b, d, and e, the angle θ is determined so that the pressing force between the valve body 16 and the seat member 38 at the lowest temperature in the usage state and the pressing force between the valve body 16 and the seat member 38 at the highest temperature in the usage state do not change.

[0049] In this embodiment, the seat member 38 and the O-ring 50 are made of a material having a relatively larger linear expansion coefficient than the valve body 14 and the valve element 16. As an example, the valve body 14 and the valve element 16 may be made of PPS (polyphenylene sulfide), the seat member 38 may be made of PTFE (fluororesin), and the O-ring 50 may be made of synthetic rubber.

[0050] The port member 44 is fixed to the valve body 14 by welding with the insertion portion 56 inserted into the valve chamber 12 and the flange 54 abutting against the end face of the valve body 14 .

[0051] In the flow path switching valve 10 of the present embodiment, the O-ring 50, the seat member 38, the valve body 16, and the seat member 38 are inserted in this order from the opening of the valve chamber 12, and then the insertion portion 56 of the port member 44 to which the O-ring 50 is attached is inserted with a predetermined force into the valve chamber 12 so as to compress the O-ring 50, and the flange 54 of the port member 44 is welded to the side surface of the valve body 14.

[0052] (Action, effect) In the flow path switching valve 10 of this embodiment, the valve body 16, two seat members 38, and two O-rings 50 are arranged in series inside the valve chamber 12, and the O-ring 50 in the O-ring groove 48 and the O-ring 50 in the O-ring groove 60 are sealed in a compressed state within the O-ring groove.

[0053] As shown in FIG. 3, in the flow path switching valve 10 of this embodiment, the seat member 38 on the right side of the arrow (right side of the drawing) has its base end surface 38b (the surface opposite the valve body) opposite the inclined seal surface 38A constantly abutting against the bottom 46a of the annular recess 46, and the seat member 38 on the left side of the arrow (left side of the drawing) has its base end surface 38b (the surface opposite the valve body) opposite the inclined seal surface 38A constantly abutting against the bottom 58a of the annular recess 58.

[0054] Therefore, when the base end surface 38b of the seat member 38 is in contact with the bottom 46a of the annular recess 46, the groove depth of the O-ring groove 48 and the distance from the groove bottom of the O-ring groove 48 to the base end surface 38b of the seat member 38 are the same. Similarly, when the base end surface 38b of the seat member 38 is in contact with the bottom 58a of the annular recess 58, the groove depth of the O-ring groove 48 and the distance from the groove bottom of the O-ring groove 60 to the base end surface 38b of the seat member 38 are the same.

[0055] For this reason, to determine the elastic force of O-ring 50 pressing seat member 38 against valve body 16 (the compression rate of the O-ring), it is sufficient to determine the compression rate of O-ring groove 60 by controlling two dimensions, namely, the groove depths of O-ring groove 48 and O-ring groove 60 and the wire diameter of O-ring 50, which makes it easy to control the dimensions of the members.

[0056] In addition, the outer peripheral surface 38c of the seat member 38 (the outer peripheral surface of the seat member 38 in the circumferential direction about the axis O2) is separated from the annular recess 46 (58) so as not to come into contact with the annular recess 46 (58). Therefore, the seat member 38 is not subjected to pressure from the valve body 14 or the port member 44 in the circumferential direction about the axis O2, which makes it easier to manage the dimensions of the member and also makes it possible to suppress deformation of the seat member 38 and changes in the angle of the inclined seal surface 38A.

[0057] Next, a mechanism by which the pressing force between the valve body 16 and the seat member 38 at the lowest temperature in the usage state and the pressing force between the valve body 16 and the seat member 38 at the highest temperature in the usage state are unlikely to change in the flow path switching valve 10 of this embodiment will be described.

[0058] The seat member 38 is biased toward the valve body 16 by the compressed O-ring 50 , and the inclined seal surface 38 A of the seat member 38 is in contact with the outer periphery of the valve body 16 .

[0059] In this embodiment, it is assumed that the linear expansion coefficient of the material constituting the seat member 38 and the O-ring 50 is relatively larger than the linear expansion coefficient of the material constituting the valve element 16 and the valve body 14.

[0060] In the present embodiment, if a gap is provided between the outer periphery of the seat member 38 and the inner periphery of the valve chamber 12 so as not to hinder radial expansion of the seat member 38, when the temperature of the seat member 38 rises, the diameter of the seat member 38 increases and the inclined seal surface 38A moves away from the valve body 14 in the radial direction of the seat member 38, thereby decreasing the pressing force pressing the valve disc 16.

[0061] In other words, since not only the dimension of the seat member 38 in the thickness direction (axial direction) but also the dimension of the seat member 38 in the radial direction is related to the pressing force of the seat member 38 against the valve body 16, by setting the angle θ of the inclined sealing surface 38A abutting against the valve body 16 to an appropriate angle, it is possible to prevent the force pressing against the valve body 16 caused by the expansion of the seat member 38 from changing even if a temperature change occurs (in other words, even if the dimension of the seat member 38 changes due to a temperature change).

[0062] In this embodiment, the linear expansion coefficients of the respective components are taken into consideration, and the values ​​of a, b, d, and e described above are determined, and the pressing force between the valve body 16 and the seat member 38 at the lowest temperature in the operating state and the pressing force between the valve body 16 and the seat member 38 at the highest temperature in the operating state do not change due to temperature changes, that is, the angle θ of the inclined seal surface 38A is determined so that the pressing force between the valve body 16 and the seat member 38 does not change due to temperature changes. In the flow path switching valve 10 of this embodiment, the determined angle θ is 57.9°. Note that this angle θ includes an error of 10% or less (i.e., the angle θ=57.9±5.79°). The angle θ can also be determined by simulation, experiment, or the like.

[0063] As a result, at both the minimum and maximum temperatures during use, the seat member 38 is pressed against the valve body 16 essentially by the elastic force of the O-ring 50 alone, making the torque required to rotate the valve body 16 less susceptible to the effects of temperature, and realizing a flow path switching valve 10 in which the valve body 16 can be rotated with a small torque.

[0064] In the flow path switching valve 10 of this embodiment, the rotational force required to drive the valve body 16 is prevented from increasing with increasing temperature, so there is no need to use a rotary drive unit 18 with a large rotational force, and it is possible to use a small unit with a small rotational force, which makes it possible to reduce the size of the flow path switching valve 10.

[0065] [Other embodiments] Although one embodiment of the present invention has been described above, the present invention is not limited to the above, and it goes without saying that the present invention can be implemented in various modified forms without departing from the spirit and scope of the present invention.

[0066] In the above embodiment, the O-ring 50 is attached to the O-ring groove 48 formed in the right-side first wall surface 12R and the O-ring groove 60 formed in the port member 44, and the seat member 38 is pressed against the valve body 16. However, the present invention is not limited to this, and an O-ring groove may be formed in the seat member 38, and the O-ring 50 may be attached to the O-ring groove formed in the seat member 38.

[0067] It goes without saying that the number and arrangement of the inlets and outlets (inlet and outlet) formed in the valve body 14 can be appropriately changed depending on the application location of the flow path switching valve 10. In the above embodiment, a three-way valve has been described as an example of the flow path switching valve 10, but it goes without saying that it may also be, for example, a two-way valve or a switching valve with four or more ways.

[0068] Furthermore, the flow path switching valve 10 in the above embodiment is intended to be used for flow path switching in the engine compartment of a vehicle (such as an engine cooling circuit or an electronic device cooling circuit), but the use is not limited to this, and it is of course possible to use it for flow path switching in a hot water supply system, for example. [Explanation of symbols]

[0069] 10. Flow path switching valve 12 Valve chamber 14 Valve body 16 Valve body 18 Rotation drive unit 38 Sheet material 38A Inclined Seal Face 46 Annular recess 48 O-ring groove (retaining groove) 50 O-ring (elastic body) 58 Annular recess 60 O-ring groove (retaining groove)

Claims

1. a valve body having a valve chamber formed therein and an inlet / outlet opening in at least a pair of opposing wall surfaces of the valve chamber; a ball-shaped valve body that is rotatably disposed in the valve chamber and has a flow path formed therein; an annular seat member that is disposed between the valve body and the inlet / outlet to seal the gap between the valve body and the inlet / outlet, the seat member having a side surface opposite to the valve body in contact with the wall surface and an outer circumferential surface spaced apart from the valve body; an inclined seal surface formed at an open end of the seat member on the valve body side, inclined at a certain angle θ with respect to the axis when viewed in a cross section along the axis of the seat member, and in contact with an outer peripheral surface of the valve body; a retaining groove provided on either a side surface of the seat member facing the valve body or the wall surface of the valve body, the retaining groove being recessed in a direction of the axis of the seat member; an elastic body that is received in the retaining groove and is compressed with the side surface of the seat member in contact with the wall surface, thereby pressing the seat member against the valve body; a rotary drive unit that rotates the valve body so that a communication state of the plurality of inlets and outlets is selectively switched through the flow path of the valve body; and Equipped with The value of the angle θ is determined so that the pressing force between the valve body and the seat member at the lowest temperature in the usage state does not change from the pressing force between the valve body and the seat member at the highest temperature in the usage state. Flow path switching valve.

2. The wall surface of the valve body is provided with an annular recess in which the seat member is disposed, a side portion of the sheet member always contacts a bottom portion of the annular recess; The retaining groove is provided at the bottom of the annular recess, and the elastic body is fitted into the retaining groove. The flow path switching valve according to claim 1 .

3. The angle θ is 57.9±5.79°; The flow path switching valve according to claim 1 or 2.

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