rotary valve

Abstract

To provide a rotary valve using a packing for enhancing the performance of regulating the leakage of liquid.SOLUTION: A packing 55 of a rotary valve 10 has a sheet-shaped packing body part 56 as a skeleton part arranged between an outer peripheral face 43 of a valve body part 42 of a valve element 41 and an inner peripheral face 22 of a body main body part 15. In the packing body part 56, a plurality of through-holes 57 each penetrating therethrough in the radial direction are formed at least in the state of neighboring each other in the peripheral direction. The plurality of through-holes 57 include the through-hole 57 opposed to an inner periphery opening 25 formed in the inner peripheral face 22 in the radial direction. At least around each through-hole 57 out of the inner peripheral face of the packing body part 56, an annular inner periphery lip part 61 is formed which is protruded inward in the radial direction to contact the outer peripheral face 43.SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] The present invention relates to a rotary valve that switches a liquid flow path by rotating a valve element. [Background technology]

[0002] A rotary valve that switches a liquid flow path by rotating a valve element is known (see, for example, Patent Document 1). Fig. 19 shows one form of a rotary valve. A rotary valve 100 includes a valve element 105 and a housing 104 having a cylindrical body 101. The valve element 105 includes a valve main body 106 housed within the body 101. The valve element 105 is rotatably supported in the housing 104 by a shaft extending along an axis AL.

[0003] Inner peripheral openings 103 through which liquid flows are formed on an inner peripheral surface 102 of the body 101 at multiple locations in the circumferential direction of the valve main body 106. A plurality of movable flow paths 107 through which liquid flows are formed in the valve element 105. Each movable flow path 107 has an outer peripheral opening 109 that opens on the outer peripheral surface of the valve main body 106.

[0004] In the rotary valve 100 configured as described above, the communication state between the outer peripheral opening 109 and the inner peripheral opening 103 is changed by rotation of the valve body 106 about the axis AL, thereby switching the liquid flow path.

[0005] In the rotary valve 100, a packing 113 is disposed between the inner peripheral surface 102 of the body 101 and the outer peripheral surface of the valve main body 106. The framework of the packing 113 is formed by a packing main body 114. The packing main body 114 has a plurality of through holes 116 formed therein, each passing through the valve main body 106 in the radial direction. The plurality of through holes 116 includes a through hole 116 that faces the inner peripheral opening 103 in the radial direction.

[0006] Furthermore, in the rotary valve 100, the multiple inner circumferential openings 103 are formed in a concentrated state in a partial region of the inner circumferential surface 102 in the circumferential direction. The multiple inner circumferential openings 103 in the body 101, the multiple outer circumferential openings 109 in the valve main body 106, and the multiple through holes 116 in the packing main body 114 are all formed adjacent to each other at least in the circumferential direction.

[0007] Furthermore, in the rotary valve 100, as shown in Figures 19 and 20, a tapered portion 111 that becomes thinner radially outward is formed between circumferentially adjacent outer peripheral openings 109 on the outer periphery of the valve body 106. In contrast, the inner periphery 115 of the packing body 114 is formed smoothly. The tapered portion 111 comes into contact with the inner periphery 115, thereby increasing the surface pressure that occurs as a result of this contact. Note that 118 in Figure 20 is a low-friction sheet that is attached to the packing body 114 to reduce friction between the packing 113 and the valve body 106. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Patent Publication No. 2021-105412 Summary of the Invention [Problem to be solved by the invention]

[0009] However, in the conventional rotary valve 100 shown in Figures 19 and 20, the portion of the inner circumferential surface 115 of the packing body 114 that comes into contact with the tapered portion 111 is pressed radially outward, forming a minute concave mark 117 on the inner circumferential surface 115.

[0010] When the valve body 106 rotates to switch the flow path and the contact point with the packing body 114 changes, that is, even after the tapered portion 111 moves away from the pressed mark 117 in the circumferential direction, the pressed mark 117 remains formed (remains) on the inner circumferential surface 115. This phenomenon is more likely to occur the longer the period during which the valve body 105 is stopped before being rotated, that is, the longer the period during which the tapered portion 111 is pressed.

[0011] 20, when the rotation is stopped again, another tapered portion 111 contacts the inner circumferential surface 115, forming a new pressing mark 117. At this time, it is desirable that the other tapered portion 111 contacts the same location on the inner circumferential surface 115 of the packing main body 114 as the location that the tapered portion 111 contacted when the rotation was previously stopped. This is to ensure that the pressing mark 117 is formed in the same location.

[0012] However, due to component tolerances, the rotation accuracy of the valve element 105 driven by the actuator, and the like, it is possible that the new tapered portion 111 may come into contact with a location on the inner circumferential surface 115 that is circumferentially shifted from the location where the tapered portion 111 made contact when the previous rotation was stopped, as shown in FIG. 21 . In this case, a new pressing mark 117 is formed. At this time, depending on the circumferential position of the formed pressing mark 117, the surface pressure generated between the packing main body 114 and the tapered portion 111 may decrease. For example, if the new pressing mark 117 is formed in a state that is connected to the previously formed pressing mark 117 in the circumferential direction, the surface pressure will be lower than if the new pressing mark 117 were formed in the same location as the previously formed pressing mark 117. There is a risk of liquid leaking from the location where the surface pressure has decreased. [Means for solving the problem]

[0013] Various aspects of rotary valves for solving the above problems will be described below. [Mode 1] A valve disc includes a housing having a cylindrical body, a valve body having a valve main body portion accommodated within the body and rotatably supported on the housing by a shaft portion extending in the axial direction, and a packing having a sheet-like packing main body portion disposed between the outer circumferential surface of the valve main body and the inner circumferential surface of the body as a skeleton portion, wherein a plurality of inner circumferential openings through which a liquid flows are opened adjacent to each other in at least the circumferential direction in a partial area of the inner circumferential surface of the body in the circumferential direction of the valve main body, and the valve disc is formed with a plurality of movable flow paths through which the liquid flows, each movable flow path having an outer circumferential opening that opens on the outer circumferential surface of the valve main body, and the plurality of outer circumferential openings are a rotary valve in which the outer peripheral opening and the inner peripheral opening are formed adjacent to each other at least in the circumferential direction, and the communication state between the outer peripheral opening and the inner peripheral opening is changed by rotation of the valve main body around the axis, thereby switching the flow path of the liquid, wherein the packing main body has a plurality of through holes formed adjacent to each other at least in the circumferential direction, each penetrating the valve main body in a radial direction, the plurality of through holes including one that faces the inner peripheral opening in the radial direction, and an annular inner peripheral lip portion that protrudes radially inward in the radial direction and contacts the outer peripheral surface of the valve main body is formed on the inner peripheral surface of the packing main body at least around each through hole.

[0014] In the above configuration, the inner lip is formed on the inner peripheral surface of the packing body, and the inner lip is elastically compressed and deformed radially outward when it comes into contact with the outer peripheral surface of the valve body. The tapered portion of the valve body does not come into contact with the inner peripheral surface of the packing body. As a result, concave pressure marks are less likely to be formed on the inner lip.

[0015] Even if the part on the outer surface of the valve body that comes into contact with the inner surface of the packing body differs between the previous stop of rotation of the valve disc and the current stop of rotation due to component tolerances, the tapered portion of the inner lip will not be pressed against the valve body, leaving no marks. The marks will not be formed in circumferentially displaced locations between the previous stop of rotation of the valve disc and the current stop of rotation. The formation of marks in circumferentially displaced locations will not result in a decrease in surface pressure, making it difficult for liquid to leak from areas with reduced surface pressure. This improves the packing's ability to prevent liquid leakage.

[0016] [Aspect 2] In the rotary valve according to [Aspect 1], when the boundary between each of the circumferentially adjacent inner lip portions and the adjacent inner lip portion is defined as a circumferential lip boundary portion, and the portion of the packing body where the circumferentially adjacent inner lip portions are formed is defined as a circumferential body intermediate portion, a pair of circumferential intermediate wall portions protruding radially inward are formed on the inner surface of the body at locations that sandwich the circumferential body intermediate portion from both sides in the circumferential direction, and the circumferential body intermediate portion is located between the pair of circumferential intermediate wall portions.

[0017] According to the above configuration, circumferential intermediate wall portions are located on both circumferential sides of the circumferential intermediate portion of the packing body. The two circumferential intermediate wall portions position the circumferential intermediate portion relative to the body. The two circumferential intermediate wall portions also restrict circumferential movement of the circumferential intermediate portion relative to the body. Therefore, even if circumferential liquid pressure acts on the packing, the packing is restricted from shifting in the circumferential direction relative to the body. The packing maintains its ability to restrict liquid leakage.

[0018] [Aspect 3] A rotary valve as described in [Aspect 1] or [Aspect 2], wherein, in each of the circumferentially adjacent inner lip portions, the boundary portion with the adjacent inner lip portion is defined as a circumferential lip boundary portion, and in each of the circumferentially adjacent inner lip portions, the portion of the packing body where the circumferentially adjacent circumferential lip boundary portions are formed is defined as a circumferential body intermediate portion, and in each of the circumferentially adjacent inner lip portions, the circumferentially adjacent circumferential lip boundary portions are configured by a common circumferential lip boundary portion extending in the axial direction at the circumferential body intermediate portion.

[0019] According to the above configuration, the common circumferential lip boundary extends in the axial direction in the circumferential body intermediate portion. This common circumferential lip boundary also serves as the circumferential lip boundary of each of the circumferentially adjacent inner lip portions. Therefore, it is possible to reduce the circumferential dimension of the circumferential body intermediate portion compared to when the circumferentially adjacent circumferential lip boundaries are formed in the circumferential body intermediate portion while being circumferentially spaced apart from each other.

[0020] [Aspect 4] In a rotary valve according to [Aspect 1] or [Aspect 2], when the boundary between each of the circumferentially adjacent inner lip portions and the adjacent inner lip portion is defined as a circumferential lip boundary portion, and the portion of the packing body where the circumferentially adjacent circumferential lip boundary portions are formed in each of the circumferentially adjacent inner lip portions is defined as a circumferential body intermediate portion, the circumferentially adjacent circumferential lip boundary portions in each of the circumferentially adjacent inner lip portions are formed in the circumferential body intermediate portion while being spaced apart from each other in the circumferential direction.

[0021] According to the above configuration, the region sandwiched between adjacent circumferential lip boundaries functions as a buffer region. Therefore, when a liquid pressure acts on one circumferential lip boundary toward the other circumferential lip boundary, if the circumferential lip boundary elastically deforms in the buffer region, the liquid pressure is less likely to act on the other circumferential lip boundary. The other circumferential lip boundary is less susceptible to the liquid pressure applied to the one circumferential lip boundary. As a result, the packing's ability to prevent liquid leakage is further improved.

[0022] [Aspect 5] A rotary valve as described in [Aspect 4], wherein a groove portion extending in the axial direction is formed in the circumferential body intermediate portion at a location between adjacent circumferential lip boundary portions in the circumferential direction, recessed inward in the radial direction from the outer surface of the circumferential body intermediate portion in the radial direction.

[0023] As the packing undergoes compressive elastic deformation, a compression reaction force is generated that pushes back against the valve body. This compression reaction force is necessary to create a seal between the outer circumferential surface of the valve body and the inner circumferential surface of the body. However, if the compression reaction force is too large, the sliding resistance generated between the valve body and the packing increases as the valve disc rotates, increasing the rotational torque required to rotate the valve disc.

[0024] In this regard, with the above-described configuration, the radial dimension of the grooved portion in the circumferential body intermediate portion between adjacent circumferential lip boundaries is smaller than the dimension without the grooved portion. This reduces the compressive reaction force of the packing. As the valve disc rotates, the sliding resistance between the valve body and the packing decreases, enabling a reduction in the rotational torque required to rotate the valve disc.

[0025] [Aspect 6] A rotary valve described in [Aspect 5], wherein the inner surface of the body is formed with a protrusion extending in the axial direction while protruding inward in the radial direction, and the protrusion is inserted into the groove.

[0026] According to the above configuration, the protrusion inserted into the groove positions the circumferential body intermediate portion relative to the body. The protrusion also restricts circumferential movement of the circumferential body intermediate portion relative to the body. Therefore, even if circumferential liquid pressure acts on the packing, the packing is restricted from shifting in the circumferential direction relative to the body. The packing maintains its ability to restrict liquid leakage. [Effects of the Invention]

[0027] According to the present invention, the packing can improve the ability to prevent liquid leakage. [Brief explanation of the drawings]

[0028] [Figure 1] FIG. 1 is a perspective view of a rotary valve according to a first embodiment. [Figure 2] FIG. 2 is a perspective view of a body in the first embodiment. [Figure 3] FIG. 3 is an exploded perspective view of the rotary valve according to the first embodiment. [Figure 4] FIG. 4 is a cross-sectional perspective view of the body in the first embodiment. [Figure 5] FIG. 5 is a development view illustrating an example of the arrangement of a plurality of outer peripheral openings by developing the outer peripheral surface of the valve body in FIG. 3 into a plane. [Figure 6] FIG. 6 is a cross-sectional perspective view showing the body to which the packing is attached together with one of the covers in the first embodiment. [Figure 7] 7 is a cross-sectional view taken along the axis of the rotary valve of FIG. 1. FIG. [Figure 8] FIG. 8 is a cross-sectional view of the rotary valve of FIG. 1 taken along a plane perpendicular to the axis thereof. [Figure 9] 9 is a cross-sectional view taken along a plane perpendicular to the axis of the rotary valve of FIG. 1 and different from that of FIG. [Figure 10] FIG. 10 is an enlarged cross-sectional view of the X portion of FIG. [Figure 11]FIG. 11 is a front view of one packing in FIG. 3 as viewed from the inner peripheral side. [Figure 12] FIG. 12 is an exploded perspective view of a part of the body, the valve element, and the packing of the rotary valve of the second embodiment. [Figure 13] FIG. 13 is a cross-sectional perspective view showing the body to which the packing is attached together with one of the covers in the second embodiment. [Figure 14] FIG. 14 is a cross-sectional view taken along the axis of the rotary valve of the second embodiment. [Figure 15] FIG. 15 is a cross-sectional view of a rotary valve according to the second embodiment taken along a plane perpendicular to the axis thereof. [Figure 16] FIG. 16 is a cross-sectional view taken along a plane perpendicular to the axis of the rotary valve of the second embodiment and different from that of FIG. [Figure 17] FIG. 17 is an enlarged cross-sectional view of the Y portion of FIG. [Figure 18] FIG. 18 is a partial front view showing the packing in FIG. 12 as seen from the inner peripheral side, with a part cut away. [Figure 19] FIG. 19 is a cross-sectional view of a conventional rotary valve taken along a plane perpendicular to the axis thereof. [Figure 20] FIG. 20 is an enlarged cross-sectional view of a portion Z in FIG. [Figure 21] FIG. 21 is a partially enlarged cross-sectional view showing a case where the tapered portion of the valve body contacts the packing at a different location from that shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0029] (First embodiment) A first embodiment of the present invention will now be described with reference to FIGS. 1 and 3, the rotary valve 10 includes a housing 11, a valve element 41, a support mechanism, a shaft seal member 52, a seal member 53, and a packing 55. Next, each part will be described.

[0030] Here, to identify the positional relationship of each part of the rotary valve 10, the axis AL of the valve element 41 is used as a reference. The direction along the axis AL is referred to as the "axial direction." The radial direction from the axis AL is referred to as the "radial direction." The direction along a circle centered on the axis AL is referred to as the "circumferential direction."

[0031] <Housing 11> The housing 11 includes a body 12 and a pair of covers 31 and 35 . [Body 12] As shown in Figures 2 and 3, the body 12 includes a connection base 13 and a main body portion 15. The connection base 13 is shaped like a rectangular pillar and forms the bottom of the body 12. The bottom surface 14 of the connection base 13 is flat. The main body portion 15 is shaped like a cylinder that extends in the axial direction and is open at both ends. The main body portion 15 forms the portion of the body 12 above the connection base 13. An annular step portion 16 having an annular shape centered on the axis AL is formed at each end of the main body portion 15 in the axial direction (see Figure 4).

[0032] A gasket mounting portion 21 is formed on most of the inner periphery of the main body 15, excluding the arc-shaped top 17, and is recessed and curved so as to bulge outward in the radial direction. The gasket mounting portion 21 is where a gasket 55 (see FIG. 3, etc.), which will be described later, is mounted. The inner periphery 22 of the gasket mounting portion 21 has a larger diameter than the inner periphery 18 of the top 17. As described above, the gasket mounting portion 21 occupies most of the inner periphery of the main body 15, and therefore the inner periphery 22 of the gasket mounting portion 21 will hereinafter be referred to as the "inner periphery 22 of the main body 15."

[0033] At both ends of the packing mounting portion 21 in the circumferential direction, at the boundary with the top portion 17, a pair of step surfaces 23 extending in both the radial and axial directions are formed. The body 12 is formed with a plurality of connection flow paths 24 connecting the bottom surface 14 of the connection base 13 and a partial region (bottom) of the inner circumferential surface 22 of the body main portion 15 in the circumferential direction. The plurality of connection flow paths 24 are formed in a state of being aligned in both the circumferential direction and the axial direction. In the first embodiment, the plurality of connection flow paths 24 are formed in a plurality of rows in the circumferential direction and in a plurality of rows in the axial direction. Each connection flow path 24 extends in a direction perpendicular to the bottom surface 14 of the connection base 13. Each of the plurality of connection flow paths 24 is connected to a plurality of external housing flow paths (not shown) provided outside the housing 11. Liquid supplied to the housing 11 through the external housing flow path passes through one of the connection flow paths 24 and flows into the body main portion 15. Liquid that has passed through one of the connection flow paths 24 flows out to the external housing flow path.

[0034] Here, the term "liquid" includes multiple liquids. Multiple liquids include multiple types of liquids with different components as well as multiple liquids of the same type. Multiple liquids of the same type include multiple identical liquids as well as multiple liquids with the same components but different temperatures or other factors, such as viscosity.

[0035] 7 and 9, the multiple connection flow paths 24 each open at the bottom of the inner circumferential surface 22 of the main body portion 15. Each opening on the inner circumferential surface 22 is referred to as an "inner circumferential opening 25" to distinguish it from other openings in the rotary valve 10. The multiple inner circumferential openings 25 are adjacent to each other both circumferentially and axially.

[0036] [Cover 31, 35] As shown in FIGS. 1, 3, and 7, a pair of covers 31, 35 are disposed at both axial ends of the main body portion 15. Each cover 31, 35 has an annular shape centered on the axis AL and includes an annular protrusion 32 that protrudes toward the other cover 35, 31. The annular protrusion 32 of each cover 31, 35 is inserted into the corresponding annular step portion 16 of the main body portion 15. Each cover 31, 35 is attached to the main body portion 15 by fastening members (not shown), such as bolts and nuts. Note that each cover 31, 35 may be attached to the main body portion 15 by a mounting means other than fastening members, such as welding. Both open ends of the main body portion 15 in the axial direction are closed by these covers 31, 35.

[0037] Alternatively, one of the covers 31, 35 may be formed integrally with the body 12. In this case, the main body portion 15 has a cylindrical shape with one axial end closed and only one axial end open. In other words, the main body portion 15 has a bottomed cylindrical shape with one axial end open.

[0038] <Valve body 41> 3 and 7, the valve element 41 includes a valve main body 42 and a shaft 49. The valve main body 42 is cylindrical and extends in the axial direction, and is housed within the body main body 15. The valve main body 42 has an outer peripheral surface 43 that faces the inner peripheral surface 22 of the body main body 15. The outer peripheral surface 43 is formed by a cylindrical surface centered on the axis AL.

[0039] The outer diameter of the valve main body 42 is set to a value that allows the gasket 55, described later, to be elastically deformed radially outward to seal the space between the inner surface 22 of the body main body 15 and the outer surface 43 of the valve main body 42 around the inner opening 25.

[0040] The shaft portion 49 protrudes in the axial direction from the center of the end surface of the valve body portion 42 on the cover 31 side. The valve body 41 has a plurality of movable flow paths 44 through which liquid flows. Each movable flow path 44 has an outer peripheral opening that opens on the outer peripheral surface 43 of the valve main body 42. The plurality of outer peripheral openings are formed adjacent to each other in the circumferential and axial directions.

[0041] 5 shows an example of a developed view of the outer peripheral surface 43 of the valve main body 42, on which a plurality of outer peripheral openings 46 to 48 are formed, as developed on a plane. The outer peripheral surface 43 is partitioned into a plurality of unit areas 45 in the axial direction and a plurality of unit areas 45 in the circumferential direction. The outer peripheral openings 46 to 48 include the following:

[0042] (A) A peripheral opening 46 consisting of a plurality of unit areas 45 that are continuous in the circumferential direction. (B) A peripheral opening 47 consisting of a plurality of unit areas 45 that are continuous in the axial direction. (C) Peripheral opening 48 that combines (A) and (B) above.

[0043] (D) Although not shown in FIG. 5, the peripheral opening may be formed by one unit area 45. The arrows in FIG. 5 indicate the direction of the liquid flow.

[0044] By rotating the valve body 42 around the shaft 49, the communication state between the outer peripheral openings 46 to 48 and the inner peripheral opening 25 is changed, and the liquid flow path is switched. The shaft 49 is rotated by an actuator such as an electric motor (not shown) or by manual operation.

[0045] <Support mechanism> 3, the support mechanism is a mechanism for rotatably supporting the valve body 41 relative to the housing 11. The support mechanism includes a first support mechanism portion M1 and a second support mechanism portion M2.

[0046] [First support mechanism section M1] The first support mechanism M1 is provided on the valve main body 42 and the cover 31. More specifically, a bearing hole 33 is formed in the center of the cover 31, penetrating the cover 31 in the axial direction. A shaft 49 of the valve body 41 is rotatably inserted into the bearing hole 33. The bearing hole 33 and the shaft 49 constitute the first support mechanism M1.

[0047] [Second support mechanism part M2] 3 and 6, the second support mechanism M2 includes a bottomed bearing hole (not shown) that extends axially in the valve main body 42, and a shaft 36 that is provided in the cover 35. The bearing hole is formed on the axis AL at the end of the valve main body 42 on the cover 35 side.

[0048] The shaft 36 protrudes from the center of the cover 35 toward the other cover 31. The shaft 49 is inserted into the bearing hole so as to be rotatable relative to the shaft 36. In other words, the valve body 42 is supported in the bearing hole so as to be rotatable relative to the shaft 36. The bearing hole and the shaft 36 constitute the second support mechanism M2.

[0049] <Shaft seal member 52> 3, the shaft seal member 52 is formed in an annular shape from an elastic material such as rubber. The shaft seal member 52 is disposed around the shaft portion 49, between the shaft portion 49 and the inner wall surface of the bearing hole 33 in the cover 31. The shaft seal member 52 prevents liquid in the main body portion 15 from passing between the shaft portion 49 and the inner wall surface of the bearing hole 33 and leaking out of the rotary valve 10.

[0050] <Sealing member 53> As shown in Figures 3 and 7, the seal members 53 are used to seal the fastened portions when the covers 31, 35 are attached to the main body portion 15 by fastening or the like. In this embodiment in which the pair of covers 31, 35 are fastened to the main body portion 15, two seal members 53 are used. Each seal member 53 is formed in an annular shape from an elastic material such as rubber. Each seal member 53 is disposed between the outer peripheral surface of the annular protrusion 32 of each cover 31, 35 and the inner peripheral surface of the annular step portion 16 of the main body portion 15. Each seal member 53 prevents liquid inside the main body portion 15 from leaking out of the rotary valve 10 through the gap between the annular step portion 16 and the annular protrusion 32.

[0051] Note that, when one of the covers 31, 35 is formed integrally with the body 12 as described above and the other is fastened to the main body portion 15, only one seal member 53 is used. Also, when one or both of the covers 31, 35 are welded to the main body portion 15, no seal member 53 is required between the covers 31, 35 and the main body portion 15 to be welded.

[0052] <Packing 55> 3, 10, and 11, the framework of the packing 55 is constituted by a sheet-shaped packing main body 56. As shown in FIGS. 6 and 8, the packing main body 56 is attached to the packing attachment portion 21 of the body main body 15. The packing main body 56 is disposed between the outer peripheral surface 43 of the valve main body 42 and the inner peripheral surface 22 of the body main body 15.

[0053] 9 to 11, a plurality of through holes 57 that penetrate radially are formed adjacent to each other in both the circumferential and axial directions in the packing body 56. The plurality of through holes 57 includes a through hole 57 that faces the inner peripheral opening 25 in the radial direction.

[0054] 10 , an annular inner peripheral lip portion 61 is formed on the inner peripheral surface 58 of the packing main body 56 at least around each through hole 57, protruding radially inward and contacting the outer peripheral surface 43 of the valve main body 42. An annular outer peripheral lip portion 62 is formed on the outer peripheral surface 59 of the packing main body 56 at least around each through hole 57, protruding radially outward and contacting the inner peripheral surface 22 of the body main body 15.

[0055] Furthermore, if the packing main body 56 has an area that is not radially opposed to the inner circumferential opening 25 and in which no through hole 57 is formed, an inner circumferential lip portion 61 and an outer circumferential lip portion 62 similar to those described above may be formed in this area.

[0056] When there is no need to particularly distinguish between the inner peripheral lip portion 61 and the outer peripheral lip portion 62, they may be simply referred to as "lip portion 63." 9 and 11, in each of the circumferentially adjacent lip portions 63, the boundary between the adjacent lip portion 63 is referred to as a "circumferential lip boundary portion 64." In each of the axially adjacent lip portions 63, the boundary between the adjacent lip portion 63 is referred to as an "axial lip boundary portion 65." In each of the lip portions 63 located at both ends in the circumferential direction, the portion located outermost in the circumferential direction is referred to as a "circumferential lip outer end portion 66." In each of the axially adjacent lip portions 63, the portion located outermost in the axial direction is referred to as an "axial lip outer end portion 67."

[0057] Furthermore, the portion of the packing body 56 where the circumferential lip boundaries 64 are formed in each of the circumferentially adjacent lip portions 63 is referred to as the "circumferential body intermediate portion 68." The portion of the packing body 56 where the axially adjacent axial lip boundaries 65 are formed in each of the axially adjacent lip portions 63 is referred to as the "axial body intermediate portion 69." The portion of the packing body 56 where the circumferential lip outer end portion 66 is formed is referred to as the "circumferential body outer end portion 71." The portion of the packing body 56 where the axial lip outer end portion 67 is formed is referred to as the "axial body outer end portion 72."

[0058] [Packing 55 installation structure] 4 and 10 , a pair of circumferential intermediate walls 73 protruding radially inward are formed at each of a plurality of locations on the inner circumferential surface 22 of the main body portion 15 that sandwich the circumferential intermediate portion 68 from both sides in the circumferential direction. The circumferential intermediate walls 73 are spaced apart from each other in the circumferential direction. Each circumferential intermediate portion 68 is disposed between the pair of circumferential intermediate walls 73.

[0059] 4 and 6, a pair of axial intermediate walls 75 protruding radially inward are formed at each of a plurality of locations on the bottom of the inner peripheral surface 22 of the main body portion 15, axially sandwiching the axial main body intermediate portion 69 from both sides in the axial direction. The axial intermediate walls 75 are spaced apart from each other in the axial direction. Each axial main body intermediate portion 69 is disposed between the pair of axial intermediate walls 75.

[0060] An axially outer end wall portion 76 protruding radially inward is formed on the inner peripheral surface 22 of the main body portion 15 at a predetermined distance in the axial direction from each cover 31, 35. The axially outer main body end portion 72 is disposed between the cover 31, 35 and the adjacent axially outer end wall portion 76.

[0061] [Other structures of Packing 55] In the first embodiment, as shown in FIGS. 3, 8, and 9, the packing main body 56 is divided into a plurality (three) of main body segments 77, 78, and 79 in the circumferential direction. The division occurs at the circumferential main body intermediate portion 68. Each of the main body segments 77 and 79 has a circumferential main body outer end portion 71 at its end circumferentially farther from the main body segment 78, and a circumferential main body intermediate portion 68 at its end circumferentially closer to the main body segment 78. In contrast, the main body segment 78 has the circumferential main body intermediate portion 68 at both ends in the circumferential direction. A plurality (two) of lip portions 63 are formed in the circumferential direction on the inner circumferential surface 58 and the outer circumferential surface 59 of each of the main body segments 77 to 79. The boundary between each of the main body segments 77 to 79 and the adjacent main body segment 77 to 79 is located between the pair of circumferential intermediate walls 73.

[0062] Furthermore, in the first embodiment, as shown in Fig. 11 , in each of the circumferentially adjacent lip portions 63, the circumferentially adjacent circumferential lip boundaries 64 are configured by a common circumferential lip boundary 64 that extends in the axial direction at the circumferential body intermediate portion 68. In other words, in the circumferential body intermediate portion 68, the circumferentially adjacent circumferential lip boundaries 64 are joined together to form a single boundary that extends in the axial direction. In the first embodiment, the common circumferential lip boundary 64 is formed in the circumferential center of the circumferential body intermediate portion 68, but it may be formed at a location away from the center in the circumferential direction.

[0063] Furthermore, in each of the axially adjacent lip portions 63, the axially adjacent axial lip boundaries 65 are configured by a common axial lip boundary 65 that extends in the circumferential direction at the axial body intermediate portion 69. In other words, at the axial body intermediate portion 69, the axially adjacent axial lip boundaries 65 are joined together to form a single axial lip boundary 65 that extends in the circumferential direction. In the first embodiment, the common axial lip boundary 65 is formed at the center of the axial body intermediate portion 69 in the axial direction, but it may also be formed at a location axially away from the center.

[0064] 10, a low-friction sheet 84 made of a material with a lower coefficient of friction than the packing body 56, such as a fluororesin, is attached to the inner circumferential surface 58 of the packing body 56. The low-friction sheet 84 comes into contact with the outer circumferential surface 43 of the valve body 42, thereby reducing the friction between the packing 55 and the valve body 42 and reducing the load required to rotate the valve disc 41. Instead of the sheet, the inner circumferential surface 58 of the packing body 56 may be coated with a material with a low coefficient of friction, such as the fluororesin.

[0065] In each figure, when describing each part of the gasket 55 using symbols, for convenience, lead lines are drawn from the corresponding parts and symbols are attached, just as in the case where the low-friction sheet 84 is not present.

[0066] <Operation of the First Embodiment> [About assembling packing 55] When assembling the packing 55 to the main body portion 15, all of the main body segments 77 to 79 are attached to the packing attachment portion 21 in a state where they are in contact with each other in the circumferential direction, as shown in FIGS.

[0067] The circumferential body intermediate portion 68 of each main body segment 77-79 is inserted and positioned between a pair of circumferential intermediate walls 73. The circumferential intermediate walls 73 position the circumferential body intermediate portion 68 relative to the main body 15. The boundary portions (circumferential body intermediate portions 68) of each main body segment 77-79 with the adjacent main body segment 77-79 are positioned between the pair of circumferential intermediate walls 73 in a state of contact with each other (see FIGS. 6 and 9). The circumferential intermediate walls 73 position the boundary portions relative to the main body 15 in the circumferential direction. The circumferential body outer end portion 71 of each main body segment 77, 79 approaches or contacts the step surfaces 23 at both circumferential ends of the packing mounting portion 21 (see FIGS. 8 and 9).

[0068] Additionally, the axial main body intermediate portion 69 of the main body segment 78 is inserted and disposed between the pair of axial intermediate wall portions 75. Both axial intermediate wall portions 75 determine the axial position of the axial main body intermediate portion 69 relative to the main body portion 15.

[0069] In the main body segment 78 , the axially outer main body end portions 72 at both axial ends are brought into close proximity to or into contact with the corresponding axially outer end wall portions 76 of the main body portion 15 . When the rotary valve 10 is assembled, each axial body outer end portion 72 is positioned by being sandwiched from both sides in the axial direction by the axial outer end wall portion 76 and the annular protrusion portion 32 of the cover 31, 35.

[0070] [Operation of rotary valve 10] When the rotary valve 10 is operated, the valve element 41 is rotated about the axis AL of the shaft portion 49 by an actuator or manually. This rotation changes the state of communication between the inner circumferential opening 25 on the inner circumferential surface 22 of the body main portion 15 and the outer circumferential openings 46-48 (see FIG. 5) on the outer circumferential surface 43 of the valve main portion 42, as shown in FIG. 9, thereby switching the liquid flow path. That is, the inner circumferential opening 25 of the body main portion 15 and the outer circumferential openings 46-48 of the valve main portion 42 are communicated through the through-hole 57 of the packing main portion 56 located between them. Then, the liquid flows through the inner circumferential opening 25 of the body main portion 15, the through-hole 57 of the packing 55, the movable flow path 44 of the valve main portion 42, and the other inner circumferential opening 25 of the body main portion 15 as a flow path. By rotating the valve main body 42, one of the outer peripheral openings 46 to 48 of the valve main body 42 that is connected to the inner peripheral opening 25 of the body main body 15 via the through hole 57 of the packing main body 56 is switched, thereby switching the flow path.

[0071] [Sealing with Packing 55] Here, in the first embodiment in which the inner circumferential lip portion 61 is formed on the inner circumferential surface 58 of the packing main body 56, the inner circumferential lip portion 61 is compressed elastically outward in the radial direction upon contact with the outer circumferential surface 43 of the valve main body 42. Unlike the conventional rotary valve 100 described using Figures 19 to 21, the tapered portion 111 on the outer periphery of the valve main body 106 does not come into contact with the inner circumferential surface 58 of the packing main body 56. As a result, it is less likely that a concave pressing mark 117 will be formed on the inner circumferential lip portion 61.

[0072] Even if the location of the outer surface 43 of the valve body 42 that comes into contact with the inner surface 58 of the packing body 56 differs between the previous rotation stop of the valve disc 41 and the current rotation stop due to component tolerances, the tapered portion 111 does not leave a pressing mark 117 on the inner lip 61. The pressing mark 117 is not left at a circumferentially shifted location between the previous rotation stop of the valve disc 41 and the current rotation stop.

[0073] As a result, a decrease in surface pressure due to the formation of pressure marks 117 at locations offset in the circumferential direction is unlikely to occur. Liquid flows through the locations where the surface pressure is decreased, so that liquid is unlikely to flow between the inner and outer regions of annular inner lip portion 61, i.e., leak.

[0074] 10 , a circumferential intermediate wall portion 73 is located on each circumferential side of each circumferential main body intermediate portion 68 of the packing 55. The circumferential intermediate wall portions 73 restrict circumferential movement of the circumferential main body intermediate portions 68 relative to the body main portion 15.

[0075] 4 and 6, an axial intermediate wall portion 75 is located on each axial side of the axial main body intermediate portion 69 of the main body segment 78. The axial intermediate wall portions 75 restrict axial movement of the axial main body intermediate portion 69 relative to the main body portion 15.

[0076] Additionally, an axial outer end wall portion 76 and an annular protrusion portion 32 of the covers 31, 35 are located on both axial sides of each of the axial outer main body end portions 72. The axial outer end wall portions 76 and the annular protrusion portions 32 restrict axial movement of the axial main body outer end portions 72 relative to the body main portion 15.

[0077] 11 , the common circumferential lip boundary 64 extends in the axial direction in the circumferential body intermediate portion 68. This common circumferential lip boundary 64 also serves as the circumferentially adjacent circumferential lip boundary 64 in each of the circumferentially adjacent lip portions 63. Furthermore, the common axial lip boundary 65 extends in the circumferential direction in the axial body intermediate portion 69. This common axial lip boundary 65 also serves as the axially adjacent axial lip boundary 65 in each of the axially adjacent lip portions 63.

[0078] <Effects of the first embodiment> 9 and 10 , an annular inner peripheral lip portion 61 that protrudes radially inward and contacts the outer peripheral surface 43 of the valve main body 42 is formed on the inner peripheral surface 58 of the packing main body 56, at least around each through-hole 57. Therefore, compared to the case where the tapered portion 111 of the valve main body 106 contacts the inner peripheral surface 115 of the packing main body 114, the sealing performance of the packing 55 between the outer peripheral surface 43 of the valve main body 42 and the inner peripheral surface 22 of the body main body 15 can be improved.

[0079] (1-2) As shown in Figures 4 and 10, a pair of circumferential intermediate walls 73 protruding radially inward are formed on the inner circumferential surface 22 of the main body portion 15 at locations that sandwich the circumferential intermediate body portion 68 of the packing main body portion 56 from both sides in the circumferential direction. The circumferential intermediate body portion 68 is disposed between these circumferential intermediate walls 73. Therefore, even if circumferential liquid pressure acts on the packing 55, the packing 55 is prevented from shifting in the circumferential direction relative to the main body portion 15, and the packing 55 can maintain its ability to prevent liquid leakage.

[0080] (1-3) As shown in Figures 3, 8, and 9, in the first embodiment, the packing main body 56 is divided at the circumferential main body intermediate portion 68 into a plurality of main body segments 77-79. However, as shown in Figure 9, the boundary portion (the circumferential main body intermediate portion 68) between each main body segment 77-79 and the adjacent main body segment 77-79 is in contact with each other and is disposed between the pair of circumferential intermediate walls 73. Therefore, even if circumferential liquid pressure acts on each main body segment 77-79, it is possible to prevent each of the main body segments 77-79 from shifting in the circumferential direction relative to the body main portion 15, and the effect of (1-2) above can be effectively achieved.

[0081] (1-4) As shown in Figures 4 and 6, a pair of axially intermediate walls 75 protruding radially inward are formed at multiple locations on the bottom of the inner circumferential surface 22 of the main body portion 15 in both the circumferential and axial directions. The two axially intermediate walls 75 are formed at locations that axially sandwich the axially intermediate body portion 69 (see Figure 11) of the main body segment 78 of the packing 55 that is located in the circumferential center (the bottom of the main body portion 15). The two axially intermediate walls 75 are formed at locations that axially sandwich the axially intermediate body portion 69 of the main body segment 78 that is located in the circumferential center (the bottom of the main body portion 15). The axially intermediate body portion 69 is disposed between the two axially intermediate walls 75. Therefore, even if axial liquid pressure acts on the main body segment 78, the axial displacement of the main body segment 78 with respect to the main body portion 15 is prevented, and the packing 55 can maintain its ability to prevent liquid leakage.

[0082] (1-5) As shown in Figures 4, 6, and 7, an axial outer end wall portion 76 that protrudes radially inward is formed at the bottom of the inner circumferential surface 22 of the main body portion 15 at a location a predetermined distance axially away from the covers 31, 35. The axial main body outer end portion 72 (see Figure 11) is disposed between the annular protrusion 32 of the covers 31, 35 and the adjacent axial outer end wall portion 76. Therefore, even if axial liquid pressure acts on the main body segment 78, the main body segment 78 can be prevented from shifting axially relative to the main body portion 15. The packing 55 maintains its ability to prevent liquid leakage.

[0083] (1-6) As shown in Fig. 11 , in each of the circumferentially adjacent lip portions 63, the circumferentially adjacent circumferential lip boundary portions 64 are configured by a common circumferential lip boundary portion 64 extending in the axial direction in the circumferential body intermediate portion 68. Therefore, compared to when the circumferentially adjacent circumferential lip boundary portions 64 are formed in the circumferential body intermediate portion 68 while being spaced apart from each other in the circumferential direction, the circumferential dimension of the circumferential body intermediate portion 68 can be reduced. Consequently, the packing 55 can be made smaller in size in the circumferential direction.

[0084] (1-7) In each of the axially adjacent lip portions 63, the axially adjacent axial lip boundaries 65 are configured by a common axial lip boundary 65 extending in the circumferential direction in the axial body intermediate portion 69. Therefore, the dimension of the axial body intermediate portion 69 in the axial direction can be made smaller than when the axially adjacent axial lip boundaries 65 are formed in the axial body intermediate portion 69 while being spaced apart from each other in the axial direction. Consequently, the packing 55 can be made smaller in size in the axial direction.

[0085] (Second embodiment) Next, a second embodiment of the present invention will be described with reference to FIGS. 12 to 18, focusing on the differences from the first embodiment.

[0086] 12, 15, and 18, in the second embodiment, a single sheet-like packing is used as the packing 55. The packing 55 is curved in an arc shape centered on the axis AL.

[0087] In each of the circumferentially adjacent lip portions 63, the circumferentially adjacent circumferential lip boundaries 64 are formed in the circumferential body intermediate portion 68 while being spaced apart from each other in the circumferential direction. In each of the axially adjacent lip portions 63, the axially adjacent axial lip boundaries 65 are formed in the axial body intermediate portion 69 while being spaced apart from each other in the axial direction.

[0088] 12, 13, and 17, a groove 85 is formed in each circumferential body intermediate portion 68 at a location between adjacent circumferential lip boundaries 64. In the second embodiment, the groove 85 is formed in the circumferential center of the circumferential body intermediate portion 68, but it may also be formed at a location circumferentially spaced from the center. Each groove 85 extends in the axial direction from the radially outer surface (outer peripheral surface 59) of the circumferential body intermediate portion 68 while being recessed radially inward.

[0089] 12, 15, and 16, protrusions 86 are formed at multiple locations circumferentially spaced apart on the inner circumferential surface 22 of the main body portion 15. Each protrusion 86 extends axially while protruding radially inward. The tip of each protrusion 86 is inserted into a groove 85 that faces the protrusion 86 in the radial direction.

[0090] The configuration of the second embodiment other than the above is the same as that of the first embodiment. Therefore, in the second embodiment, the same elements as those described in the first embodiment are denoted by the same reference numerals, and redundant description will be omitted.

[0091] <Operation of the Second Embodiment> [About assembling packing 55] As shown in FIGS. 12 and 13, when the packing 55 is assembled to the main body portion 15, the packing 55 made of a single sheet is attached to the packing attachment portion 21.

[0092] 17, the packing 55 is attached to the packing attachment portion 21 so that the tip ends of the protrusions 86 of the body main body portion 15 fit into grooves 85 provided at multiple locations in the circumferential direction of each circumferential main body intermediate portion 68. The protrusions 86 inserted into the grooves 85 position the circumferential main body intermediate portion 68 relative to the body main body portion 15 in the circumferential direction, in place of the pair of circumferential intermediate wall portions 73 (see FIG. 10) in the first embodiment.

[0093] 12, 14, and 18, the axial main body intermediate portion 69 is inserted and positioned between a pair of axial intermediate walls 75, and the axial positioning of the axial main body intermediate portion 69 with respect to the main body portion 15 is achieved, similarly to the first embodiment. Also, as shown in FIGS. 15 and 16, the circumferential main body outer end portion 71 approaches or contacts the stepped surfaces 23 at both circumferential ends of the packing mounting portion 21, similarly to the first embodiment. Furthermore, as shown in FIGS. 14 and 18, the axial main body outer end portion 72 is sandwiched from both sides in the axial direction by the axial outer end wall portions 76 of the main body portion 15 and the annular protrusions 32 of the covers 31, 35, similarly to the first embodiment.

[0094] [Sealing with Packing 55] 17 and 18 , in the rotary valve 10 of the second embodiment, in each of the circumferentially adjacent lip portions 63, the circumferentially adjacent circumferential lip boundaries 64 are spaced apart from each other in the circumferential direction. The area sandwiched between the adjacent circumferential lip boundaries 64 functions as a buffer area. Therefore, when a liquid pressure acts on one circumferential lip boundary 64 toward the other circumferential lip boundary 64, if the former circumferential lip boundary 64 elastically deforms in the buffer area, the liquid pressure is less likely to act on the latter circumferential lip boundary 64.

[0095] 18 , in the rotary valve 10 of the second embodiment, in each of the axially adjacent lip portions 63, the axially adjacent axial lip boundaries 65 are spaced apart from each other in the axial direction. The area sandwiched between the adjacent axial lip boundaries 65 functions as a buffer area. Therefore, when a liquid pressure acts on one axial lip boundary 65 toward the other axial lip boundary 65, if the former axial lip boundary 65 elastically deforms in the buffer area, the liquid pressure is less likely to act on the latter axial lip boundary 65.

[0096] Here, as the packing 55 undergoes compressive elastic deformation, a compression reaction force is generated that pushes back the valve main body 42. This compression reaction force is necessary to seal between the outer peripheral surface 43 of the valve main body 42 and the inner peripheral surface 22 of the body main portion 15. However, if the compression reaction force is too large, the sliding resistance generated between the valve main body 42 and the packing 55 increases as the valve disc 41 rotates.

[0097] In this regard, according to the second embodiment, the radial dimension of the portion of the circumferential body intermediate portion 68 where the groove portion 85 is formed is smaller than the dimension when the groove portion 85 is not formed. As a result, the compressive reaction force of the packing 55 is reduced. As the valve body 41 rotates, the sliding resistance generated between the valve body portion 42 and the packing 55 decreases.

[0098] Furthermore, the protrusion 86 inserted into the groove 85 restricts the circumferential movement of the circumferential main body intermediate portion 68 relative to the main body portion 15 . <Effects of the second embodiment> Therefore, according to the second embodiment, the same effects as those (1-1), (1-4), and (1-5) in the first embodiment can be obtained. In addition, the following effects can be obtained. Among these effects, the effect (2-1) in particular is an alternative to the effect (1-6), the effect (2-2) is an alternative to the effect (1-7), and the effect (2-4) is an alternative to the effect (1-2).

[0099] 17 and 18, in each of the circumferentially adjacent lip portions 63, the circumferentially adjacent circumferential lip boundaries 64 are formed in the circumferential body intermediate portion 68 while being spaced apart from each other in the circumferential direction. Therefore, even if a liquid pressure acts on one circumferential lip boundary 64 toward the other circumferential lip boundary 64, the other circumferential lip boundary 64 is less susceptible to the liquid pressure applied to the one circumferential lip boundary 64. This allows for further improvement in the ability of the packing 55 to prevent liquid leakage.

[0100] (2-2) As shown in Fig. 18, in each of axially adjacent lip portions 63, axially adjacent axial lip boundaries 65 are formed in the axial body intermediate portion 69 while being spaced apart from each other in the axial direction. Therefore, even if a liquid pressure acts on one axial lip boundary 65 toward the other axial lip boundary 65, the other axial lip boundary 65 is less susceptible to the liquid pressure applied to the one axial lip boundary 65. This allows for further improvement in the ability of the packing 55 to prevent liquid leakage.

[0101] (2-3) As shown in FIG. 17 , a groove 85 is formed in the circumferential body intermediate portion 68 at a location between adjacent circumferential lip boundary portions 64. The groove 85 extends in the axial direction while being recessed radially inward from the outer surface (outer peripheral surface 59) of the circumferential body intermediate portion 68 in the radial direction. This reduces the compression reaction force that occurs with the compressive elastic deformation of the packing 55. This reduces the sliding resistance that occurs between the valve body 42 and the packing 55 as the valve disc 41 rotates. As a result, the rotational torque required to rotate the valve disc 41 can be reduced.

[0102] (2-4) As shown in Figure 17, a protrusion 86 extending in the axial direction and protruding radially inward is formed on the inner peripheral surface 22 of the main body portion 15, and this protrusion 86 is inserted into the groove portion 85. Therefore, even if a circumferential liquid pressure acts on the packing 55, the packing 55 can be prevented from shifting in the circumferential direction relative to the main body portion 15. The packing 55 can maintain its ability to prevent liquid leakage.

[0103] (2-5) The packing body 56 is not divided but is formed as a single sheet. Therefore, the number of parts can be reduced compared to when the packing body 56 is divided into a plurality of body segments 77 to 79.

[0104] <Example of change> The above-described embodiments can be modified as follows: The above-described embodiments and the following modifications can be combined with each other to the extent that no technical contradiction occurs.

[0105] [Matters regarding packing 55] In the second embodiment, as in the first embodiment, in each of the circumferentially adjacent lip portions 63, the circumferentially adjacent circumferential lip boundaries 64 may be configured by a common circumferential lip boundary 64 extending in the axial direction in the circumferential body intermediate portion 68. Furthermore, in each of the axially adjacent lip portions 63, the axially adjacent axial lip boundaries 65 may be configured by a common axial lip boundary 65 extending in the circumferential direction in the axial body intermediate portion 69.

[0106] In the first embodiment, as in the second embodiment, in each of the circumferentially adjacent lip portions 63, the circumferentially adjacent circumferential lip boundaries 64 may be formed in the circumferential body intermediate portion 68 while being spaced apart from each other in the circumferential direction. Also, in each of the axially adjacent lip portions 63, the axially adjacent axial lip boundaries 65 may be formed in the axial body intermediate portion 69 while being spaced apart from each other in the axial direction.

[0107] In each of the circumferentially adjacent lip portions 63 , the circumferentially adjacent circumferential lip boundaries 64 may come into contact with each other in the circumferential body intermediate portion 68 . In each of the axially adjacent lip portions 63 , the axially adjacent axial lip boundary portions 65 may contact each other in the axial body intermediate portion 69 .

[0108] The number of circumferential lip boundaries 64 in the circumferential body intermediate portion 68 may be different between the inner circumferential lip portion 61 and the outer circumferential lip portion 62 . The number of axial lip boundaries 65 in the axial body intermediate portion 69 may be different between the inner peripheral lip portion 61 and the outer peripheral lip portion 62 .

[0109] Of the grooves 85 in the circumferential main body intermediate portion 68 and the protrusions 86 in the main body portion 15, only the protrusions 86 may be omitted. Alternatively, both the grooves 85 and the protrusions 86 may be omitted. In these cases, the circumferential main body intermediate portion 68 may be sandwiched from both circumferential sides by a pair of circumferential intermediate walls 73, as in the first embodiment. In this way, the circumferential movement of the circumferential main body intermediate portion 68 is restricted by both circumferential intermediate walls 73.

[0110] In the first embodiment, the number of main body segments 77 to 79 can be changed as long as there is a plurality of them. That is, the number of main body segments 77 to 79 may be two, three or more.

[0111] In the second embodiment, it is sufficient that each protrusion 86 is inserted into at least a portion of the radial groove 85. Therefore, as in the second embodiment, each protrusion 86 may be inserted into a portion of the radial groove 85 or into the entire groove 85.

[0112] [Other matters] The multiple inner peripheral openings 25 may be formed adjacent to each other only in the circumferential direction, out of the circumferential direction and the axial direction. In this case, the multiple through holes 57 that penetrate the packing body 56 in the radial direction may be formed adjacent to each other only in the circumferential direction, out of the circumferential direction and the axial direction.

[0113] The outer peripheral openings 46 to 48 may be adjacent to each other only in the circumferential direction, out of the circumferential direction and the axial direction. [Explanation of symbols]

[0114] 10...Rotary valve 11. Housing 12...Body 22…Inner peripheral surface 25...Inner opening 36,49...Shaft 41...Valve body 42...Valve body 43...Outer surface 44... Movable flow path 46, 47, 48...Outer opening 55...Gasket 56...Packing body 57...Through hole 61...Inner lip 64... Circumferential lip boundary 68…Circumferential main body middle part 73…Circumferential intermediate wall part 85...Groove 86...Protrusion

Claims

1. a housing having a cylindrical body; a valve element having a valve main body portion accommodated in the body and rotatably supported by the housing by a shaft portion extending in the axial direction; and a packing having a sheet-like packing main body portion as a skeleton portion, the packing being disposed between an outer peripheral surface of the valve main body portion and an inner peripheral surface of the body, a plurality of inner circumferential openings through which a liquid flows are opened adjacent to each other in the circumferential direction and the axial direction in a partial region of the inner circumferential surface of the body in the circumferential direction of the valve main body, The valve body is formed with a plurality of movable flow paths through which the liquid flows, Each movable flow path has an outer peripheral opening that opens on the outer peripheral surface of the valve body portion, The plurality of outer peripheral openings are formed adjacent to each other in the circumferential direction and the axial direction, a rotary valve in which a communication state between the outer circumferential opening and the inner circumferential opening is changed by rotation of the valve body about the stem, thereby switching a flow path of the liquid, a plurality of through holes each penetrating the valve body in a radial direction are formed in the packing body so as to be adjacent to each other in the circumferential direction and the axial direction, and the plurality of through holes include a through hole facing the inner circumferential opening in the radial direction, an annular inner peripheral lip portion that protrudes radially inward and contacts the outer peripheral surface of the valve body portion at least around each through hole on the inner peripheral surface of the packing body portion; In each of the inner circumferential lip portions adjacent to each other in the axial direction, a boundary portion between the adjacent inner circumferential lip portion and the adjacent inner circumferential lip portion is defined as an axial lip boundary portion, In the packing body, when a portion where the axial lip boundary portions adjacent to each other in the axial direction are formed in each of the inner peripheral lip portions adjacent to each other in the axial direction is defined as an axial body intermediate portion, a pair of axial intermediate wall portions protruding radially inward are formed on the inner circumferential surface of the body at locations that are peripheral edges of the inner circumferential opening and that sandwich the axial main body intermediate portion from both sides in the axial direction, The rotary valve has an axial body intermediate portion disposed between the pair of axial intermediate wall portions.

2. In each of the inner circumferential lip portions adjacent to each other in the circumferential direction, a boundary portion between the adjacent inner circumferential lip portion is defined as a circumferential lip boundary portion, In the packing body portion, in each of the inner peripheral lip portions adjacent in the circumferential direction, when a portion where the circumferential lip boundary portions adjacent in the circumferential direction are formed is defined as a circumferential body intermediate portion, a pair of circumferential intermediate wall portions protruding radially inward are formed on the inner circumferential surface of the body at locations that sandwich the circumferential main body intermediate portion from both sides in the circumferential direction, The rotary valve according to claim 1 , wherein the circumferential body intermediate portion is disposed between the pair of circumferential intermediate wall portions.

3. In each of the inner circumferential lip portions adjacent to each other in the circumferential direction, a boundary portion between the adjacent inner circumferential lip portion is defined as a circumferential lip boundary portion, In the packing body portion, in each of the inner peripheral lip portions adjacent in the circumferential direction, when a portion where the circumferential lip boundary portions adjacent in the circumferential direction are formed is defined as a circumferential body intermediate portion, 3. The rotary valve according to claim 1, wherein in each of the circumferentially adjacent inner circumferential lip portions, the circumferentially adjacent circumferential lip boundaries are configured by a common circumferential lip boundary extending in the axial direction in the circumferential body intermediate portion.

4. In each of the inner circumferential lip portions adjacent to each other in the circumferential direction, a boundary portion between the adjacent inner circumferential lip portion is defined as a circumferential lip boundary portion, In the packing body portion, in each of the inner peripheral lip portions adjacent in the circumferential direction, when a portion where the circumferential lip boundary portions adjacent in the circumferential direction are formed is defined as a circumferential body intermediate portion, 3. The rotary valve according to claim 1, wherein in each of the circumferentially adjacent inner circumferential lip portions, the circumferentially adjacent circumferential lip boundary portions are formed in the circumferential body intermediate portion while being spaced apart from each other in the circumferential direction.

5. 5. The rotary valve according to claim 4, wherein a groove portion extending in the axial direction is formed in the circumferential body intermediate portion at a location between the circumferential lip boundary portions adjacent to each other in the circumferential direction, the groove portion being recessed radially inward from an outer surface of the circumferential body intermediate portion in the radial direction.

6. a protrusion extending in the axial direction and protruding inward in the radial direction is formed on the inner circumferential surface of the body, The rotary valve according to claim 5 , wherein the protrusion is inserted into the groove.

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