Valve device

Abstract

To provide a valve device capable of reducing a risk that sliding between two valve elements is inhibited by solidification of residual components of a liquid.SOLUTION: A valve device 10 includes a fixed valve element 14 and a driving valve element 22 disposed in an inlet-side space 12d through which a liquid flows. A surface of the fixed valve element 14 has a sliding surface 140 opposed to the driving valve element 22, and a surface of the driving valve element 22 has a sliding surface 220 opposed to the fixed valve element 14. An opening degree between an inlet-side space 12d and an outlet-side space 12e is changed by sliding between the sliding surfaces 140, 220. An inclined face X21 inclined at an acute angle with respect to the sliding surface at a mating side, of the sliding surface 140 is continuous to an edge portion of the sliding surface 220.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to a valve device. [Background technology]

[0002] Patent Document 1 describes a valve device that includes two valve bodies, one of which slides relative to the other to adjust the flow rate of liquid. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2014-072376 Summary of the Invention [Problem to be solved by the invention]

[0004] According to the inventor's investigation, in such a valve device, when parts are replaced, the liquid is drained from the flow path, which makes the flow path prone to drying. When the flow path dries, the remaining components of the liquid (e.g., calcium and silica) solidify. This solidification may impede the sliding between the two valve bodies.

[0005] In view of the above, an object of the present invention is to reduce the possibility that the sliding between two valve bodies is hindered due to solidification of residual components of a liquid in a valve device. [Means for solving the problem]

[0006] The invention described in claim 1 to achieve the above object is: A valve device for adjusting a flow rate of a liquid, which is a cooling water, in a vehicle, comprising: a first valve body (14) disposed in a first flow path (12d) through which the liquid flows; a second valve body (22) disposed in the first flow path, a surface of the first valve body having a first sliding surface (140) facing the second valve body; The surface of the second valve body has a second sliding surface (220) facing the first valve body, The first flow path and the second flow path ( 12e) the degree of opening between the At least one of the first sliding surface and the second sliding surface has an edge portion having the The inclined surface (X1 1, X13, X15, X21, X23, 224) in a row And, Auxiliary surfaces (X11, X13, X15, X21, X23) are connected to the edge of the inclined surface opposite to the at least one sliding surface, The auxiliary surface has an inclination angle with respect to the mating sliding surface smaller than that of the inclined surface. It is a valve device.

[0007] In this way, at least one of the first and second sliding surfaces has an inclined surface that is inclined at an acute angle to the mating sliding surface at its edge. This makes it easier for a liquid pool to form between this inclined surface and the mating sliding surface due to surface tension when liquid is drained from the valve device. This makes it harder for residual components to solidify between the first and second sliding surfaces. This in turn reduces the possibility of the sliding between the first and second valve bodies being hindered.

[0008] The reference symbols in parentheses attached to each component indicate an example of the correspondence between the component and specific components described in the embodiments described below. [Brief description of the drawings]

[0009] [Figure 1] FIG. 2 is a plan view of the valve device according to the first embodiment. [Diagram 2] FIG. 2 is a view taken along the arrow II in FIG. [Diagram 3] FIG. 3 is a view taken along the arrow III in FIG. 2. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV of FIG. [Diagram 5] FIG. [Figure 6] FIG. [Figure 7] FIG. 7 is an enlarged view of part VII in FIG. [Figure 8] FIG. 8 is an enlarged view of part VIII in FIG. [Figure 9] FIG. 5 is an enlarged view of part IX in FIG. [Figure 10] FIG. 4 is a partially enlarged cross-sectional view of a comparative example. [Figure 11] 7 is an enlarged view of part VII when the valve disc is misaligned. FIG. [Figure 12] FIG. 7 is an enlarged view of part VII in the second embodiment. [Figure 13] FIG. 7 is an enlarged view of part VII in the third embodiment. [Figure 14] FIG. 7 is an enlarged view of part VII in the fourth embodiment. [Figure 15] FIG. 7 is an enlarged view of part VII in the fifth embodiment. [Figure 16] FIG. 13 is an enlarged view of part VII in the sixth embodiment. [Figure 17] 7 is an enlarged view of part VII when the valve disc is misaligned. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, a number of embodiments of the present invention will be described with reference to the drawings. In the following multiple embodiments, the same or equivalent parts are denoted by the same reference numerals, and the description thereof may be omitted.

[0011] (First embodiment) A first embodiment will be described with reference to the drawings. A valve device 10 of this embodiment is a control valve used in a temperature control device for controlling vehicle interior air conditioning and battery temperature control in an electric vehicle. Specifically, the valve device 10 is disposed in a coolant circuit that circulates coolant through a heat exchanger for vehicle interior air conditioning and a heat exchanger for battery temperature control, and adjusts the flow rate of coolant flowing through the coolant circuit.

[0012] Temperature control devices for electric vehicles require fine adjustment of temperatures according to the vehicle interior air conditioning and the battery, and therefore the valve device 10 used in the temperature control devices for electric vehicles is required to have more precise flow control than those used in the coolant circuits of internal combustion engines.

[0013] The valve device 10 is installed in a fluid circulation circuit in which fluid circulates for conditioning the vehicle interior air and regulating the battery temperature. The valve device 10 is capable of opening, closing, and switching the flow path in which the valve device 10 is installed in the fluid circulation circuit, as well as controlling the flow rate of the fluid to each flow path with high precision. A liquid is used as the fluid. For example, LLC containing ethylene glycol and water is used. LLC is an abbreviation for Long Life Coolant.

[0014] 1 to 3, the valve device 10 has a housing 12 that forms a fluid passage therein for circulating a fluid. The valve device 10 is configured as a three-way valve in which an inlet portion 12a through which the fluid flows, a first outlet portion 12b through which the fluid flows out, and a second outlet portion 12c through which the fluid flows out are provided in the housing 12. The valve device 10 not only functions as a flow path switching valve, but also functions as a flow rate adjustment valve that adjusts the flow rate ratio between the fluid flowing from the inlet portion 12a to the first outlet portion 12b and the fluid flowing from the inlet portion 12a to the second outlet portion 12c.

[0015] The valve device 10 is configured as a disk valve that opens and closes the valve by rotating a disk-shaped valve element about a shaft axis CL of a shaft 18, which will be described later.

[0016] 4 and 5, the valve device 10 accommodates a fixed valve body 14, a shaft 18, a rotor 20, a compression spring 26, a first torsion spring 28, a second torsion spring 30, etc. inside a housing 12. In addition, the valve device 10 has a drive unit 16 and the like disposed outside the housing 12.

[0017] The housing 12 is a non-rotating member that does not rotate. The housing 12 is formed of, for example, a resin material. The housing 12 has a bottomed cylindrical main body 120 and a main body cover 124 that closes an opening 120a formed on one side of the main body 120 in the axial direction DRa. A seal member 13 such as an O-ring that closes the gap between the main body 120 and the main body cover 124 is disposed between them.

[0018] The axial direction DRa is a direction along the shaft axis CL. The circumferential direction about the shaft axis CL is simply called the circumferential direction DRc, and the radial direction about the shaft axis CL is simply called the radial direction DRr.

[0019] The main body 120 has a bottom wall 121 that forms the bottom surface and a side wall 122 that surrounds the shaft axis CL. The bottom wall 121 and the side wall 122, together with a main body cover 124, form an accommodation space that accommodates the fixed valve body 14, the rotor 20, etc., which will be described later. The bottom wall 121 and the side wall 122 are configured as an integrally molded product.

[0020] The bottom wall portion 121 is provided with steps corresponding to a first flow passage hole 141a and a second flow passage hole 142a of the fixed valve body 14 described later. That is, the bottom wall portion 121 has a portion facing the first flow passage hole 141a and the second flow passage hole 142a of the fixed valve body 14 described later that is farther away from the main body cover portion 124 than other portions.

[0021] The bottom wall portion 121 has a stepped portion 121a where a step is provided facing the first flow passage hole 141a and the second flow passage hole 142a of the fixed valve body 14, and a non-step portion 121b where no step is provided facing the outlet surface 149. The bottom wall portion 121 is far away from the fixed valve body 14 at the stepped portion 121a, and is close to the fixed valve body 14 at the non-step portion 121b.

[0022] Inlet portion 12a is formed in side wall portion 122 at a position closer to opening 120a than bottom wall portion 121, and first outlet portion 12b and second outlet portion 12c are formed in positions closer to bottom wall portion 121 than opening 120a. Inlet portion 12a, first outlet portion 12b, and second outlet portion 12c are configured of tubular members having flow paths formed therein.

[0023] A mounting portion 122a on which the fixed valve body 14 is mounted is provided between the portion where the inlet portion 12a is formed and the portions where the outlet portions 12b, 12c are formed on the inner side of the side wall portion 122. A receiving groove for arranging the gasket 15 is formed in the mounting portion 122a.

[0024] On the outer side of the side wall portion 122, there are provided a body mounting portion 122m for mounting the body cover portion 124 to the body portion 120 with fastening members TN, and a mounting portion 123 for mounting the valve device 10 to an electric vehicle.

[0025] The inside of the housing 12 is divided into an inlet side space 12d and an outlet side space 12e by the mounting portion 122a. The inlet side space 12d is a flow path that communicates with the inlet portion 12a inside the housing 12, and is also an accommodation space that accommodates the fixed valve body 14 and the rotor 20. The outlet side space 12e is a flow path that communicates with the first outlet portion 12b and the second outlet portion 12c inside the housing 12. The inlet side space 12d corresponds to the first flow path, and the outlet side space 12e corresponds to the second flow path.

[0026] Although not shown, a plate-shaped partition that divides the outlet side space 12e into a first outlet side space communicating with the first flow passage hole 141a and a second outlet side space communicating with the second flow passage hole 142a is set inside the main body 120. This partition is provided so as to cross the outlet side space 12e along the radial direction DRr.

[0027] The body cover part 124 is a lid member that covers the opening 120a of the body part 120. The body cover part 124 is configured to include a plate part 124a, a cover rib part 124b, a boss part 124c, a cover side wall part 124d, and a cover mounting part 124e. The body cover part 124 is configured as an integrally molded product that is molded as a whole.

[0028] The plate portion 124a is an annular portion extending in the radial direction DRr, and forms the inlet side space 12d together with the side wall portion 122 and the fixed valve body 14. The cover rib portion 124b is a portion of the body cover portion 124 that is fitted into the opening 120a of the body portion 120.

[0029] The boss portion 124c is a portion into which the shaft 18 is inserted and which rotatably supports the shaft 18. The boss portion 124c protrudes from the plate portion 124a toward one side in the axial direction DRa. A shaft seal 124h that seals the gap between the shaft 18 is provided inside the boss portion 124c, and an O-ring 124k that seals the gap between the drive unit 16 is provided outside the boss portion 124c.

[0030] The cover side wall portion 124d is cylindrical and is provided on the outer circumferential side of the boss portion 124c. The driving portion 16 is inserted between the outer circumferential portion of the boss portion 124c and the inner circumferential portion of the cover side wall portion 124d.

[0031] The cover attachment portion 124e is a portion facing the main body attachment portion 122m, and is a portion to which a fastening member TN is attached for fastening the main body portion 120 and the main body cover portion 124. The cover attachment portion 124e protrudes outward in the radial direction DRr from the outer periphery of the cover side wall portion 124d.

[0032] The fixed valve body 14 is composed of a disk-shaped member (i.e., disk valve shape) with the axial direction DRa as the thickness direction. The fixed valve body corresponds to the first valve body. The fixed valve body 14 has a sliding surface 140 as a surface on which the driven valve body 22 slides. The sliding surface 140 is a contact surface that comes into contact with a sliding surface 220 (described later) of the driven valve body 22, and is perpendicular to the shaft axis CL. The fixed valve body 14 is disposed in the inlet side space 12d.

[0033] The fixed valve body 14 is formed of a material having a smaller linear expansion coefficient and excellent wear resistance compared to the constituent material of the housing 12. The fixed valve body 14 is made of a high-hardness material having a higher hardness than the housing 12. Specifically, the fixed valve body 14 is made of ceramic. The fixed valve body 14 may be a powder molded body formed by molding ceramic powder into a desired shape by a press machine.

[0034] 5, the fixed valve body 14 has an outlet surface 149 which is the surface opposite to the sliding surface 140 and faces the outlet-side space 12e, a first flow passage inner circumferential surface 141 which surrounds a first flow passage hole 141a through which the fluid passes, and a second flow passage inner circumferential surface 142 which surrounds a second flow passage hole 142a. The fixed valve body 14 has an outer circumferential surface 144 which faces the side wall portion 122, and a rotation prevention protrusion 145 which is formed to protrude toward the side wall portion 122. The rotation prevention protrusion 145 fits into a receiving groove (not shown) formed in the side wall portion 122, thereby preventing the fixed valve body 14 from rotating relative to the housing 12.

[0035] Each of the flow passage holes 141a, 142a is formed at a position away from the shaft axis CL of the shaft 18. The first flow passage hole 141a and the second flow passage hole 142a function as a communication passage that connects the inlet side space 12d and the outlet side space 12e.

[0036] Specifically, the first flow passage hole 141a is provided in a portion of the fixed valve body 14 corresponding to the first outlet space so as to communicate with the first outlet space, and the second flow passage hole 142a is provided in a portion of the fixed valve body 14 corresponding to the second outlet space so as to communicate with the second outlet space.

[0037] A central inner peripheral surface 146 is formed at the approximate center of the fixed valve body 14. The central inner peripheral surface 146 is a wall surface surrounding a shaft insertion hole through which the shaft 18 is inserted. The central inner peripheral surface 146 has an inner diameter larger than the diameter of the shaft 18 so that the shaft 18 does not slide. The inner diameter of the central inner peripheral surface 146 increases stepwise from one side to the other side in the axial direction DRa, but may be constant from one side to the other side in the axial direction DRa. Alternatively, the inner diameter of the central inner peripheral surface 146 may decrease stepwise from one side to the other side in the axial direction DRa. A gasket 15 is disposed between the fixed valve body 14 and the mounting portion 122a to seal the gap between the fixed valve body 14 and the mounting portion 122a.

[0038] The driving unit 16 is a device for transmitting a rotational force to the shaft 18. As shown in Fig. 2, the driving unit 16 has a motor 161 as a driving source, a gear unit 162 as a power transmission member for transmitting the output of the motor 161 to the shaft 18, and a motor control circuit 163.

[0039] The motor 161 drives the shaft 18 to rotate in a forward rotation direction toward the initial rotation position and in a reverse rotation direction opposite thereto within a rotation drive range between an initial rotation position and a maximum rotation position. The motor 161 is configured as a stepping motor. The motor 161 rotates in accordance with a control signal from a motor control circuit 163 electrically connected to the motor 161. The gear unit 162 is a reducer that reduces the speed of the output of the motor 161 and transmits it to the shaft 18.

[0040] The motor control circuit 163 is a computer having a memory, which is a non-transient tangible storage medium, a processor, etc. The motor control circuit 163 executes a computer program stored in the memory, and controls the motor 161 in accordance with the computer program.

[0041] The shaft 18 is a rotating shaft that rotates about a predetermined shaft axis CL by the rotational force output by the drive unit 16. The shaft 18 extends along an axial direction DRa. Both ends of the shaft 18 in the axial direction DRa are rotatably supported by the housing 12. The shaft 18 passes through the fixed valve body 14 and the drive valve body 22 and is rotatably supported relative to the housing 12.

[0042] The shaft 18 includes a metal axial center portion 181 and a resin holder portion 182 connected to the axial center portion 181. The axial center portion 181 and the holder portion 182 are connected to each other so as to be rotatable together. The axial center portion 181 includes the shaft axis CL and extends along the axial direction DRa. The axial center portion 181 is a portion that serves as the center of rotation of the rotor 20.

[0043] The holder part 182 is connected to one side of the axial center part 181 in the axial direction DRa. The holder part 182 has a bottomed cylindrical shape. The holder part 182 has the axial center part 181 connected to the inside of the tip part on one side in the axial direction DRa. In addition, the tip part of the holder part 182 protruding to the outside of the housing 12 is connected to a gear part of the drive part 16.

[0044] The rotor 20 rotates about the axis CL of the shaft 18 by the output of the drive unit 16. The rotor 20 increases and decreases the opening degree of each of the flow path holes 141a, 142a of the fixed valve body 14 in accordance with the rotation of the shaft 18. As shown in Figures 4 and 6, the rotor 20 has a driven valve body 22 as a valve body, and a lever 24 that connects the driven valve body 22 to the shaft 18.

[0045] The driven valve body 22 is a valve body that increases and decreases the opening degree of the first passage hole 141a and the opening degree of the second passage hole 142a with the rotation of the shaft 18. The driven valve body 22 is disposed in the inlet side space 12d. The driven valve body 22 corresponds to the second valve body. The driven valve body 22 is configured of a disk-shaped member (i.e., disk valve shape) with the axial direction DRa as its thickness direction. The driven valve body 22 is disposed in the inlet side space 12d facing the fixed valve body 14 in the axial direction DRa. The driven valve body 22 has a sliding surface 220 facing the sliding surface 140 of the fixed valve body 14. The sliding surface 220 is a seal surface that seals the sliding surface 140 of the fixed valve body 14. The driven valve body 22 has an inlet surface 229 facing the inlet side space 12d on the opposite side of the sliding surface 220. The sliding surface 220 is perpendicular to the shaft axis CL. The drive valve body 22 also has an outer circumferential surface 224 that faces the side wall portion 122 on its outer periphery.

[0046] The driven valve body 22 is formed of a material having a smaller linear expansion coefficient and superior wear resistance compared to the constituent material of the housing 12. The driven valve body 22 is made of a high-hardness material having a higher hardness than the housing 12. Specifically, the driven valve body 22 is made of ceramic. The driven valve body 22 may be a powder molded body formed by molding ceramic powder into a desired shape by a press machine.

[0047] In addition, the driven valve body 22 has a flow passage inner peripheral surface 221 surrounding a flow passage hole 221a at a position offset from the shaft axis CL of the shaft 18. The flow passage hole 221a is a through hole penetrating in the axial direction DRa. The flow passage hole 221a is formed at a portion of the driven valve body 22 that overlaps with the first flow passage hole 141a and the second flow passage hole 142a in the axial direction DRa when the driven valve body 22 is rotated around the shaft axis CL. The driven valve body 22 is disposed approximately coaxially with the fixed valve body 14 and the shaft 18. The driven valve body 22 has a central inner peripheral surface 223 surrounding a shaft insertion hole through which the shaft 18 is inserted at a substantially central portion. The central inner peripheral surface 223 has a diameter larger than the diameter of the shaft 18 so that the shaft 18 does not slide. The inner diameter of the central inner circumferential surface 223 increases stepwise from one side to the other side in the axial direction DRa, but may be constant from one side to the other side in the axial direction DRa. Alternatively, the inner diameter of the central inner circumferential surface 223 may decrease stepwise from one side to the other side in the axial direction DRa.

[0048] In the valve device 10, when the drive valve body 22 is rotated so that the flow passage hole 221a overlaps with the first flow passage hole 141a in the axial direction DRa, the first flow passage hole 141a is opened. In addition, in the valve device 10, when the drive valve body 22 is rotated so that the flow passage hole 221a overlaps with the second flow passage hole 142a in the axial direction DRa, the second flow passage hole 142a is opened.

[0049] The valve element 22 is configured to be able to adjust the ratio of the flow rate of the fluid passing through the first passage hole 141a to the flow rate of the fluid passing through the second passage hole 142a. That is, the valve element 22 is configured so that the opening degree of the second passage hole 142a decreases as the opening degree of the first passage hole 141a increases.

[0050] The lever 24 is a connecting member that connects the driven valve element 22 to the shaft 18. The lever 24 is fixed to the driven valve element 22, and connects the driven valve element 22 and the shaft 18 so as to be rotatable together in a state in which the driven valve element 22 is displaceable in the axial direction DRa of the shaft 18.

[0051] The compression spring 26 is a biasing member that biases the rotor 20 against the fixed valve body 14. The compression spring 26 elastically deforms in the axial direction DRa of the shaft 18. The compression spring 26 is arranged in a compressed state in the axial direction DRa such that one end of the compression spring 26 in the axial direction DRa contacts the shaft 18 and the other end of the compression spring 26 in the axial direction DRa contacts the rotor 20. Specifically, the compression spring 26 is arranged such that one end of the compression spring 26 in the axial direction DRa contacts the inside of the holder portion 182 and the other end of the compression spring 26 in the axial direction DRa contacts the spring receiver 225 of the lever 24.

[0052] The rotor 20 is pressed against the fixed valve body 14 by the compression spring 26, thereby maintaining surface contact between the sliding surface 140 of the fixed valve body 14 and the sliding surface 220 of the driven valve body 22. The shaft 18 is disposed inside the compression spring 26.

[0053] The first torsion spring 28 is a spring that biases the shaft 18 relative to the housing 12 in a circumferential direction DRc about the shaft axis CL1 of the shaft 18. The first torsion spring 28 is disposed between the housing 12 and the shaft 18.

[0054] The first torsion spring 28 is basically used in a state where it is twisted in the circumferential direction DRc and elastically deformed. The biasing force of the first torsion spring 28 acts on the shaft 18 whether the shaft 18 is rotating or stationary. The biasing force of the first torsion spring 28 is transmitted as a rotational force from the gear portion of the drive unit 16 to the motor 161 via the shaft 18. For this reason, by disposing the first torsion spring 28 between the housing 12 and the shaft 18, rattling in the circumferential direction DRc between the drive unit 16 and the shaft 18 is suppressed.

[0055] The second torsion spring 30 is a spring that biases the lever 24 in the circumferential direction DRc relative to the shaft 18. The second torsion spring 30 is disposed between the shaft 18 and the lever 24.

[0056] The second torsion spring 30 is provided closer to the driven valve body 22 than the first torsion spring 28. One axial end of the second torsion spring 30 is engaged with a locking portion (not shown) provided on the holder portion 182, and the other end is engaged with 241 provided on the lever 24. The second torsion spring 30 biases the driven valve body 22 in the circumferential direction relative to the shaft 18. The biasing force of the second torsion spring 30 suppresses rattling in the circumferential direction Drc between the shaft 18 and the driven valve body 22.

[0057] Next, the operation of the valve device 10 of this embodiment will be described. As shown in Figs. 1 to 4, in the valve device 10, the fluid flows from the inlet 12a to the inlet space 12d as indicated by the arrow Fi. When the first flow passage hole 141a is open, the fluid flows from the inlet space 12d to the first outlet space through the flow passage hole 221a and the first flow passage hole 141a. The fluid that has flowed into the first outlet space flows out of the valve device 10 from the first outlet space through the first outlet 12b as indicated by the arrow F1o. In this case, the flow rate of the fluid passing through the first flow passage hole 141a is determined according to the opening degree of the first flow passage hole 141a. That is, the flow rate of the fluid flowing from the inlet 12a to the first outlet 12b through the first flow passage hole 141a increases as the opening degree of the first flow passage hole 141a increases. The opening degree of the first flow passage hole 141a increases as the area of ​​overlap between the first flow passage hole 141a and the flow passage hole 221a in the axial direction DRa increases.

[0058] On the other hand, when the second flow passage hole 142a is open, the fluid flows from the inlet side space 12d through the flow passage hole 221a and the second flow passage hole 142a into the second outlet side space. The fluid that flows into the second outlet side space flows out of the valve device 10 from the second outlet side space through the second outlet portion 12c as shown by the arrow F2o. In this case, the flow rate of the fluid passing through the second flow passage hole 142a is determined according to the opening degree of the second flow passage hole 142a. That is, the flow rate of the fluid that flows from the inlet portion 12a to the second outlet portion 12c through the second flow passage hole 142a increases as the opening degree of the second flow passage hole 142a increases. The opening degree of the second flow passage hole 142a increases as the area of ​​overlap between the second flow passage hole 142a and the flow passage hole 221a in the axial direction DRa increases.

[0059] The arrangement of the valve device 10 in the cooling water circuit is, for example, such that a heat exchanger Ei is arranged upstream of the inlet portion 12a, a heat exchanger E1o is arranged downstream of the first outlet portion 12b, and a heat exchanger E2o is arranged downstream of the second outlet portion 12c.

[0060] Here, the heat exchangers Ei, E1o, and E2o may be a chiller, a radiator, and a heat exchanger for a battery, respectively. Alternatively, the heat exchangers Ei, E1o, and E2o may be a chiller, a heat exchanger for a battery, and a cooler core, respectively. Alternatively, the heat exchangers Ei, E1o, and E2o may be a water-cooled condenser, a heat exchanger for a battery, and a heater core, respectively. Alternatively, the heat exchangers Ei, E1o, and E2o may be a radiator, a chiller, and a water-cooled condenser, respectively.

[0061] The chiller is a heat exchanger that cools the coolant by a refrigeration cycle (not shown). The water-cooled condenser is a heat exchanger that heats the coolant by the refrigeration cycle. The radiator is a heat exchanger that releases the hot or cold heat of the coolant to the outside of the vehicle. The battery heat exchanger is a heat exchanger that uses coolant to heat and cool the battery that generates the power for running the vehicle. The cooler core is a heat exchanger that uses coolant to cool the air sent into the vehicle cabin. The heater core is a heat exchanger that uses coolant to heat the air sent into the vehicle cabin.

[0062] The motor 161 is controlled by the motor control circuit 163 to change the rotation position in 10 or more steps (e.g., multiple steps such as 100 steps) within a range from the initial rotation position to the maximum rotation position. This allows the opening degree of the first flow path hole 141a and the second flow path hole 142a to be adjusted in multiple steps of 4 or more steps (e.g., several tens of steps) between fully closed and fully open. This is possible by using a stepping motor as the motor 161.

[0063] The structures of the fixed valve body 14 and the driven valve body 22 will be further described below. The surfaces of the fixed valve body 14 have the above-mentioned sliding surface 140, outlet surface 149, outer peripheral surface 144, first flow passage inner peripheral surface 141, second flow passage inner peripheral surface 142, and central inner peripheral surface 146. The sliding surface 140 corresponds to the first sliding surface, and the outlet surface 149 corresponds to the surface opposite to the first sliding surface. Each of the outer peripheral surface 144, the first flow passage inner peripheral surface 141, the second flow passage inner peripheral surface 142, and the central inner peripheral surface 146 corresponds to a side surface between the sliding surface 140 and the outlet surface 149.

[0064] The surface of the driven valve body 22 has the above-mentioned sliding surface 220, inlet surface 229, outer peripheral surface 224, flow path inner peripheral surface 221, and central inner peripheral surface 223. The sliding surface 220 corresponds to the second sliding surface, and the inlet surface 229 corresponds to the surface opposite to the second sliding surface. Each of the outer peripheral surface 224, flow path inner peripheral surface 221, and central inner peripheral surface 223 corresponds to a side surface between the sliding surface 220 and the inlet surface 229. The sliding between the fixed valve body 14 and the driven valve body 22 is performed between the sliding surface 220 and the sliding surface 140, so that the sliding surface 220 and the sliding surface 140 are parallel to each other.

[0065] 4, the outer diameter of the sliding surface 140 is larger than the outer diameter of the sliding surface 220. In fact, when the central axis of the shaft insertion hole of the fixed valve body 14 and the central axis of the shaft insertion hole of the driven valve body 22 are aligned with each other, the outer edge of the sliding surface 140 is located radially outwardly of the outer edge of the sliding surface 220 in the DRr direction.

[0066] As already described, the inner diameter of the central inner circumferential surface 146 and the inner diameter of the central inner circumferential surface 223 are both larger than the diameter of the axial center portion 181 of the shaft 18. Therefore, there is a gap between the central inner circumferential surface 146 and the axial center portion 181. There is also a gap between the central inner circumferential surface 223 and the axial center portion 181.

[0067] 7, in the driven valve body 22, an inclined surface X21 and an auxiliary surface X22 are formed between the outer circumferential surface 224 and the sliding surface 220. The inclined surface X21 and the auxiliary surface X22 may be formed over the entire circumferential direction of the shaft axis CL, or may be formed only at a part of the circumferential direction.

[0068] The inclined surface X21 and the auxiliary surface X22 are formed as chamfers. That is, the inclined surface X21 and the auxiliary surface X22 are shaped to prevent the sliding surface 220 and the outer circumferential surface 224 from being sharply connected to each other (for example, at a pin angle of 90°) between the sliding surface 220 and the outer circumferential surface 224.

[0069] The inclined surface X21 is connected to the edge (i.e., the outer peripheral end) of the sliding surface 220 on the outer peripheral surface 224 side, and is inclined at an acute angle with respect to the sliding surface 140. That is, the inclination angle θ1 of the inclined surface X21 with respect to the sliding surface 140 is greater than 0° and less than 90°. Here, the inclination angle θ1 refers to the inclination angle formed on the gap side (i.e., the side without material) between the driven valve body 22 and the fixed valve body 14. This is the same for all the inclination angles described below. Therefore, the inclination angle θ1 of the inclined surface X21 with respect to the sliding surface 140 being an acute angle is the same as the angle of the corner of the driven valve body 22 formed by the sliding surface 220 and the inclined surface X21 being an obtuse angle.

[0070] The significance of doing so will be explained. In the valve device 10, in order to achieve highly accurate flow control, it is desirable to reduce the sliding torque generated between the sliding surface 140 and the sliding surface 220. Furthermore, when the valve device 10 is replaced with a different part, the cooling water may be drained, and the inside of the valve device 10 may become prone to drying. When the inside of the valve device 10 dries, calcium and silica, which are residues in the fluid, may become scaled (i.e., solidify) and adhere to the area between the sliding surface 140 and the sliding surface 220. This may impede sliding.

[0071] In contrast, as described above, if the inclined surface X21 connected to the edge of the sliding surface 220 on the outer circumferential surface 224 side is inclined at an acute angle with respect to the sliding surface 140, even when the cooling water is drained, a pool WS of cooling water is likely to be formed due to surface tension in the space between the inclined surface X21 and the sliding surface 140. This is because, during use of the valve device 10, the inclined surface X21 is exposed to the inlet-side space 12d, and therefore the periphery of the inclined surface X21 is exposed to the cooling water.

[0072] This liquid pool WS protects the vicinity of the edge of the sliding surface 220 on the outer circumferential surface 224 side. Therefore, solidification of the remaining components between the sliding surface 140 and the sliding surface 220 is less likely to occur. In turn, the possibility that the sliding between the fixed valve body 14 and the driving valve body 22 will be hindered is reduced.

[0073] The auxiliary surface X22 is connected at one end to the edge of the inclined surface X21 on the opposite side to the sliding surface 220, and is connected at the other end to the outer circumferential surface 224. The inclination angle of the auxiliary surface X22 with respect to the sliding surface 140 is smaller than that of the inclined surface X21. For example, the inclination angle may be 0°.

[0074] This configuration makes it possible to increase the volume of the liquid pool WS compared to a case where the auxiliary surface X22 is not present, and thus makes it possible to delay the evaporation of the liquid pool WS. Also, since the opening of the gap formed between the inclined surface X21 and the auxiliary surface X22 and the sliding surface 140 becomes narrower, the evaporation of the liquid pool WS formed in this gap can be delayed.

[0075] 7, in the fixed valve body 14, an inclined surface X11 and an auxiliary surface X12 are formed between the outer circumferential surface 144 and the sliding surface 140. The inclined surface X11 and the auxiliary surface X12 may be formed over the entire circumferential direction of the shaft axis CL, or may be formed only at a part of the circumferential direction.

[0076] The inclined surface X11 and the auxiliary surface X12 are formed as chamfers. That is, the inclined surface X11 and the auxiliary surface X12 are shaped to prevent the sliding surface 140 and the outer circumferential surface 144 from being sharply connected to each other between the sliding surface 140 and the outer circumferential surface 144.

[0077] The inclined surface X11 is connected to the edge (i.e., the outer circumferential end) of the sliding surface 140 on the outer circumferential surface 144 side, and is inclined at an acute angle with respect to the sliding surface 220. That is, the inclination angle β1 of the inclined surface X11 with respect to the sliding surface 220 is greater than 0° and less than 90°.

[0078] The auxiliary surface X12 is connected at one end to the edge of the inclined surface X11 on the opposite side to the sliding surface 140, and is connected at the other end to the outer circumferential surface 144. The inclination angle of the auxiliary surface X12 with respect to the sliding surface 220 is smaller than that of the inclined surface X11. For example, the inclination angle may be 0°.

[0079] 8, in the driven valve body 22, an inclined surface X23 and an auxiliary surface X24 are formed between a central inner peripheral surface 223 facing the axial center portion 181 and the sliding surface 220. The inclined surface X23 and the auxiliary surface X24 may be formed over the entire circumferential circumference of the shaft axis CL, or may be formed only at a portion in the circumferential direction.

[0080] The inclined surface X23 and the auxiliary surface X24 are formed as chamfers. That is, the inclined surface X23 and the auxiliary surface X24 are shaped to prevent the sliding surface 220 and the central inner circumferential surface 223 from being sharply connected to each other between the sliding surface 220 and the central inner circumferential surface 223.

[0081] The inclined surface X23 is connected to the edge portion of the sliding surface 220 on the central inner peripheral surface 223 side, and is inclined at an acute angle with respect to the sliding surface 140. That is, the inclination angle θ2 of the inclined surface X23 with respect to the sliding surface 140 is greater than 0° and less than 90°.

[0082] In this way, if the inclined surface X23 connected to the edge of the sliding surface 220 on the central inner peripheral surface 223 side is inclined at an acute angle with respect to the sliding surface 140, even when the cooling water is drained, a pool WS of cooling water is likely to be formed due to surface tension in the space between the inclined surface X23 and the sliding surface 220. This is because, during use of the valve device 10, a gap exists between the axial center portion 181 and the central inner peripheral surface 223, so that the periphery of the inclined surface X23 is exposed to the cooling water.

[0083] This liquid pool WS protects the vicinity of the edge of the sliding surface 220 on the central inner circumferential surface 223 side. Therefore, solidification of the remaining components between the sliding surface 140 and the sliding surface 220 is less likely to occur. In turn, the possibility that the sliding between the fixed valve body 14 and the driving valve body 22 will be hindered is reduced.

[0084] The auxiliary surface X24 is connected at one end to the edge of the inclined surface X23 on the opposite side to the sliding surface 220, and is connected at the other end to the central inner peripheral surface 223. The inclination angle of the auxiliary surface X24 with respect to the sliding surface 140 is smaller than that of the inclined surface X23. For example, the inclination angle may be 0°. This configuration allows the volume of the liquid pool WS to be larger than when the auxiliary surface X24 is not present, and therefore the evaporation of the liquid pool WS can be delayed. In addition, the opening of the gap formed between the inclined surface X23 and the auxiliary surface X24 and the sliding surface 140 becomes narrower, so that the evaporation of the liquid pool WS formed in this gap can be delayed.

[0085] 8, in the fixed valve body 14, an inclined surface X13 and an auxiliary surface X14 are formed between the central inner peripheral surface 146 facing the axial center portion 181 and the sliding surface 140. The inclined surface X13 and the auxiliary surface X14 may be formed over the entire circumferential circumference of the shaft axis CL, or may be formed only at a portion in the circumferential direction.

[0086] The inclined surface X13 and the auxiliary surface X14 are formed as chamfers. That is, the inclined surface X13 and the auxiliary surface X14 are shaped to prevent the sliding surface 140 and the central inner circumferential surface 146 from being sharply connected to each other between the sliding surface 140 and the central inner circumferential surface 146.

[0087] The inclined surface X13 is connected to the edge portion of the sliding surface 140 on the central inner peripheral surface 146 side, and is inclined at an acute angle with respect to the sliding surface 220. That is, the inclination angle β2 of the inclined surface X11 with respect to the sliding surface 220 is greater than 0° and less than 90°.

[0088] The auxiliary surface X14 is connected at one end to the edge of the inclined surface X13 on the opposite side to the sliding surface 140, and is connected at the other end to the central inner circumferential surface 146. The inclination angle of the auxiliary surface X14 with respect to the sliding surface 220 is smaller than that of the inclined surface X13. For example, the inclination angle may be 0°.

[0089] 9, in the fixed valve body 14, an inclined surface X15 and an auxiliary surface X16 are formed between the first flow passage inner circumferential surface 141 facing the first flow passage hole 141a and the sliding surface 140. The inclined surface X15 and the auxiliary surface X16 may be formed on the entire circumference surrounding the first flow passage hole 141a, or may be formed only at a portion around the first flow passage hole 141a.

[0090] The inclined surface X15 and the auxiliary surface X16 are formed as chamfers. That is, the inclined surface X15 and the auxiliary surface X16 are shaped to prevent the sliding surface 140 and the first flow path inner circumferential surface 141 from being sharply connected to each other between the sliding surface 140 and the first flow path inner circumferential surface 141.

[0091] The inclined surface X15 is connected to the edge of the sliding surface 140 on the first flow path inner circumferential surface 141 side, and is inclined at an acute angle with respect to the sliding surface 220. That is, the inclination angle β3 of the inclined surface X23 with respect to the sliding surface 220 is greater than 0° and less than 90°.

[0092] In this way, if the inclined surface X15 connected to the edge of the sliding surface 140 on the first flow path inner circumferential surface 141 side is inclined at an acute angle with respect to the sliding surface 220, even when the cooling water is drained, a pool WS of cooling water is likely to be formed due to surface tension in the space between the inclined surface X15 and the sliding surface 220. This is because, during use of the valve device 10, the inclined surface X15 is exposed to the first flow path hole 141a, and therefore the periphery of the inclined surface X15 is exposed to the cooling water.

[0093] This liquid pool WS protects the vicinity of the edge of the sliding surface 140 on the first flow path inner circumferential surface 141 side. Therefore, solidification of the remaining components between the sliding surface 140 and the sliding surface 220 is less likely to occur. Furthermore, the possibility that the sliding between the fixed valve body 14 and the driving valve body 22 will be hindered is reduced.

[0094] One end of the auxiliary surface X16 is connected to the edge of the inclined surface X15 on the opposite side to the sliding surface 220, and the other end is connected to the first flow path inner circumferential surface 141. The inclination angle of the auxiliary surface X16 with respect to the sliding surface 220 is smaller than that of the inclined surface X15. For example, the inclination angle may be 0°.

[0095] This configuration makes it possible to increase the volume of the liquid pool WS compared to a case where the auxiliary surface X16 is not present, and thus makes it possible to delay evaporation of the liquid pool WS. Also, since the opening of the gap formed between the inclined surface X15 and the auxiliary surface X16 and the sliding surface 220 becomes narrower, it is possible to delay evaporation of the liquid pool WS formed in this gap.

[0096] In the fixed valve body 14, an inclined surface and an auxiliary surface similar to the inclined surface X15 and the auxiliary surface X16 may be formed between the second flow passage inner circumferential surface 142 facing the second flow passage hole 142a and the sliding surface 140. In this way, a liquid pool having the same effect is formed.

[0097] In the driven valve body 22, an inclined surface and an auxiliary surface similar to the inclined surface X15 and the auxiliary surface X16 may be formed between the flow passage inner circumferential surface 221 facing the flow passage hole 221a and the sliding surface 220. In this way, a liquid pool having the same effect is formed.

[0098] A comparative example will be described below with reference to Fig. 10. In the valve device shown in Fig. 10, the sliding surface V11 of the valve body V1 slides against the sliding surface V21 of the valve body V2. There is no chamfer between the side surface V12 of the valve body V1 and the sliding surface V11, and the side surface V12 and the sliding surface V11 are connected at a pin angle of 90°. In this case, even if a liquid pool WX is formed when the cooling water is drained, the volume of the liquid pool WX is small and it is easy to evaporate.

[0099] Returning now to the description of this embodiment, as described above, there is a gap between the central inner peripheral surface 146 and the axial center portion 181 and between the central inner peripheral surface 223 and the axial center portion 181. Therefore, the positions of the fixed valve body 14 and the driven valve body 22 relative to the axial center portion 181 may change. For example, in a normal case, as shown in Figs. 4 and 7, the outer peripheral surface 144 of the fixed valve body 14 protrudes outward in the radial direction DRr relative to the outer peripheral surface 224 of the driven valve body 22. However, there are cases where a positional deviation occurs between the fixed valve body 14 and the driven valve body 22, and the outer peripheral surface 224 protrudes outward in the radial direction DRr relative to the outer peripheral surface 144, as shown in Fig. 11.

[0100] A case where the valve device 10 is stopped in such a misaligned state and the cooling water is drained will be described below. In that case, if the inclined surface X11 connected to the edge of the sliding surface 140 on the outer circumferential surface 144 side is inclined at an acute angle with respect to the sliding surface 220 as shown in Fig. 11, even when the cooling water is drained, a pool WS of the cooling water is likely to be formed in the space between the inclined surface X11 and the sliding surface 220 due to surface tension.

[0101] This liquid pool WS protects the vicinity of the edge of the sliding surface 140 on the outer circumferential surface 144 side. Therefore, even if the cooling water is drained when the position is misaligned, solidification of the remaining components between the sliding surface 140 and the sliding surface 220 is unlikely to occur. Furthermore, the possibility that the sliding between the fixed valve body 14 and the driven valve body 22 will be hindered is reduced.

[0102] As described above, since the inclination angle of the auxiliary surface X12 with respect to the sliding surface 220 is smaller than that of the inclined surface X11, the volume of the liquid pool WS can be made larger than when the auxiliary surface X12 is not present, and thus the evaporation of the liquid pool WS can be delayed. Also, since the opening of the gap formed between the inclined surface X11 and the auxiliary surface X12 and the sliding surface 220 becomes narrower, the evaporation of the liquid pool WS formed in this gap can be delayed.

[0103] The same can be said about the central inner circumferential surfaces 146 and 223. That is, as shown in Fig. 8, there are cases where the central inner circumferential surface 146 protrudes inward in the radial direction DRr relative to the central inner circumferential surface 223, and cases (not shown) where a positional deviation occurs and the central inner circumferential surface 223 protrudes inward in the radial direction DRr relative to the central inner circumferential surface 146.

[0104] A case where the valve device 10 is stopped in such a misaligned state and the cooling water is drained will be described below. In this case, if the inclined surface X13 connected to the edge portion of the sliding surface 140 on the central inner circumferential surface 146 side is inclined at an acute angle with respect to the sliding surface 220, a pool WS of the cooling water is likely to be formed in the space between the inclined surface X13 and the sliding surface 220 due to surface tension, even when the cooling water is drained.

[0105] This liquid pool WS protects the vicinity of the edge of the sliding surface 140 on the central inner circumferential surface 146 side. Therefore, even if the cooling water is drained when the position is misaligned, solidification of the remaining components between the sliding surface 140 and the sliding surface 220 is unlikely to occur. Furthermore, the possibility that the sliding between the fixed valve body 14 and the driven valve body 22 will be hindered is reduced.

[0106] As described above, since the inclination angle of the auxiliary surface X14 with respect to the sliding surface 220 is smaller than that of the inclined surface X13, the volume of the liquid pool WS can be made larger than when the auxiliary surface X14 is not present, and thus the evaporation of the liquid pool WS can be delayed. Also, since the opening of the gap formed between the inclined surface X13 and the auxiliary surface X14 and the sliding surface 220 becomes narrower, the evaporation of the liquid pool WS formed in this gap can be delayed.

[0107] In this embodiment, any one or any two of the chamfers between the sliding surface 220 and the outer peripheral surface 224, the chamfer between the sliding surface 220 and the central inner peripheral surface 223, and the chamfer between the sliding surface 140 and the first flow path inner peripheral surface 141 may not be formed. Also, the chamfer between the sliding surface 140 and the outer peripheral surface 144 and the chamfer between the sliding surface 140 and the central inner peripheral surface 146 may not be formed. Alternatively, the presence of at least one of these five chamfers can exert an effect of reducing the possibility that the sliding between the fixed valve body 14 and the driven valve body 22 will be hindered.

[0108] In addition, in this embodiment, the inclined surfaces X11, X13, X15, X21, and X23 and the auxiliary surfaces X14, X16, X22, X24, and X12 are all flat surfaces, but as another example, they are not limited to flat surfaces.

[0109] As described above, the inclined surfaces X21, X23, X11, X13, and X15, which are inclined at an acute angle to the mating sliding surface, are connected to the edge of at least one of the sliding surfaces 140 and 220. As a result, when the coolant is drained from the valve device 1, a liquid pool is likely to form between the inclined surface and the mating sliding surface due to surface tension. This makes it difficult for the residual components between the sliding surfaces 140 and 220 to solidify. This in turn reduces the possibility that the sliding between the fixed valve body 14 and the drive valve body 22 will be hindered.

[0110] (1) In addition, the inclined surfaces X11, X13, X15, X21, and X23 are chamfered. In this way, the inclined surfaces can be appropriately formed.

[0111] (2) The valve device 10 also includes a drive unit 16 having a stepping motor that transmits a rotational force to the shaft 18. When performing high-precision flow rate control using a stepping motor in this manner, it becomes more important to reduce solidification of the remaining cooling water.

[0112] (3) Furthermore, the fixed valve body 14 and the driven valve body 22 have a disk valve shape. A disk valve-shaped valve body allows easy adjustment of the opening area and is suitable for highly accurate flow rate adjustment, so it is more important to reduce solidification of the remaining cooling water.

[0113] (4) Moreover, the sliding surface 220 rotates around the shaft axis CL to slide against the sliding surface 140. The inclined surfaces X11, X21 are continuous with the outer circumferential ends of the corresponding sliding surfaces 140, 220 that are centered on the shaft axis CL.

[0114] This outer circumferential end is far from the shaft axis CL, and therefore is a position where, when the remaining cooling water solidifies, it is highly likely that the torque acting as resistance to the rotation of the driven valve body 22 will become large. Therefore, by reducing the solidification of the cooling water at this position, it is possible to more effectively reduce the possibility that the sliding between the fixed valve body 14 and the driven valve body 22 will be hindered.

[0115] (5) Furthermore, the fixed valve body 14 and the driven valve body 22 are formed to contain ceramics. In this way, the fixed valve body 14 and the driven valve body 22 have high shape stability, so that the chamfered shape is more stably maintained even in the environment in which the valve device 10 is used.

[0116] (6) Furthermore, the valve device 10 is used in a vehicle, and the liquid used in the valve device 10 is coolant. In this case, the valve device 10 adjusts the flow path of the coolant for the vehicle, and the coolant may be drained from the valve device 10 in order to replace the coolant, so a method of leaving a liquid pool is effective.

[0117] (7) The inclined surfaces X11, X13, X15, X21, and X23 are connected to auxiliary surfaces X12, X14, X16, X22, and X24, which have smaller angles of inclination than the inclined surfaces with respect to the mating sliding surfaces 220 and 140, at the edges opposite to the connecting sliding surfaces 140 and 220. This makes it possible to increase the volume of the liquid pool WS compared to a case where there is no auxiliary surface, and thus to delay the evaporation of the liquid pool WS.

[0118] (8) The liquid flowing through the flow passage, the flow rate of which is adjusted by the valve device 10, contains water. Water is not a volatile fluid and does not dry easily. Therefore, the evaporation of the liquid pool WS can be delayed.

[0119] (9) Furthermore, the sliding surface 220 where the inclined surfaces X21, X23 are connected is the sliding surface 220 with the smaller outer diameter of the sliding surfaces 140, 220. Since the edge of the sliding surface 220 with the smaller outer diameter is often the end of the sliding contact surface of the sliding surfaces 140, 220, this can reduce the possibility that the sliding between the fixed valve body 14 and the driven valve body 22 will be hindered in many cases.

[0120] Second embodiment Next, the second embodiment will be described with reference to Fig. 12. This embodiment is different from the first embodiment in the shape of the driven valve body 22. Specifically, the configuration between the outer peripheral surface 224 and the sliding surface 220 in the driven valve body 22 is different. That is, as shown in Fig. 12, compared to the first embodiment, the auxiliary surface X22 is eliminated from the chamfer formed between the outer peripheral surface 224 and the sliding surface 220.

[0121] In this embodiment, the chamfer formed between the outer circumferential surface 224 and the sliding surface 220 has an inclined surface X21. That is, a C-chamfer is formed between the outer circumferential surface 224 and the sliding surface 220. The inclined surface X21 is connected at one edge to the edge of the sliding surface 220 on the outer circumferential surface 224 side, and at the other edge to the edge of the outer circumferential surface 224 on the sliding surface 220 side. Similarly to the first embodiment, the inclined surface X21 is inclined at an acute angle with respect to the sliding surface 140. Such an inclined surface X21 provides the same effect as the inclined surface X21 of the first embodiment.

[0122] In addition, the present embodiment differs from the first embodiment in the shape of the fixed valve body 14. Specifically, unlike the first embodiment, no chamfer is formed between the outer circumferential surface 144 and the sliding surface 140, and the outer circumferential surface 144 and the sliding surface 140 are connected to each other at a pin angle of 90°. However, in this embodiment, the configuration between the outer circumferential surface 144 and the sliding surface 140 may be the same as that in the first embodiment.

[0123] Other configurations of this embodiment are the same as those of the first embodiment. Note that, in this embodiment, in comparison with the first embodiment, not only the auxiliary surface X22 but also one or more of the auxiliary surfaces X24, X12, X14, and X16 may be eliminated.

[0124] Third embodiment Next, a third embodiment will be described with reference to Fig. 13. In this embodiment, the shape of the chamfer formed between the outer circumferential surface 224 and the sliding surface 220 is changed from that in the second embodiment.

[0125] Specifically, the inclined surface X21, which is a chamfer formed between the outer circumferential surface 224 and the sliding surface 220, is rounded outwardly.

[0126] The inclination angle of the inclined surface X21 with respect to the sliding surface 140 varies depending on the position, but the average inclination angle is greater than 0° and less than 90°. Moreover, the inclination angle is greater than 0° and less than 90° at any position. The average inclination angle is the inclination angle of a plane that connects the edge on the sliding surface 220 side to the edge on the outer circumferential surface 224 side. Such an inclined surface X21 can provide the same effect as the inclined surface X21 of the second embodiment.

[0127] The modification of this embodiment is not limited to the inclined surface X21, but can also be applied to the inclined surfaces X23, X11, X13, and X15. The modification of this embodiment is also applicable to the inclined surfaces X21, X23, X11, X13, and X15 in the case where the auxiliary surfaces X22, X24, X12, X14, and X16 are connected to each other as in the first embodiment.

[0128] (Fourth embodiment) Next, a fourth embodiment will be described with reference to Fig. 14. This embodiment differs from the first embodiment in the shape of the fixed valve body 14. Other configurations are the same as those of the first embodiment.

[0129] In the fixed valve body 14 of the present embodiment, unlike the first embodiment, no chamfer is formed between the sliding surface 140 and the outer circumferential surface 144, and the sliding surface 140 and the outer circumferential surface 144 are connected to each other at a pin angle of 90°. Even in this configuration, the inclined surface X21 and the auxiliary surface X22 can provide the same effects as the first embodiment.

[0130] The first embodiment may be modified so that the chamfer between the sliding surface 140 and the central inner circumferential surface 146 is not formed, and the sliding surface 140 and the central inner circumferential surface 146 are connected to each other at a pin angle of 90°.

[0131] Fifth embodiment Next, a fifth embodiment will be described with reference to Fig. 15. This embodiment differs from the fourth embodiment in the shape of the drive valve body 22. Other configurations are the same as those of the fourth embodiment.

[0132] In the driven valve body 22 of this embodiment, both the inclined surface X21 and the auxiliary surface X22 in the fourth embodiment are eliminated. In other words, chamfering is eliminated. The outer peripheral surface 224 and the outer peripheral end of the sliding surface 220 are connected to each other. Furthermore, the outer peripheral surface 224 is inclined at an acute angle with respect to the sliding surface 140. In other words, the inclination angle θ1 of the outer peripheral surface 224 with respect to the sliding surface 140 is greater than 0° and less than 90°. Here, the inclination angle θ1 refers to the inclination angle formed on the gap side (i.e., the side without material) between the driven valve body 22 and the fixed valve body 14.

[0133] (1) In this manner, outer peripheral surface 224 of the present embodiment is continuous with sliding surface 220 and is also continuous with inlet surface 229 on the opposite side of sliding surface 220. Since outer peripheral surface 224 is inclined at an acute angle with respect to sliding surface 220, a portion of outer peripheral surface 224, i.e., the portion of outer peripheral surface 224 in the vicinity of sliding surface 220, functions as an inclined surface.

[0134] That is, even when the cooling water is drained, a pool of cooling water WS is likely to be formed in the space between the inclined surface and the sliding surface 140 due to surface tension. This pool of cooling water WS protects the edge of the sliding surface 220 near the outer circumferential surface 224. Therefore, solidification of the remaining components between the sliding surface 140 and the sliding surface 220 is unlikely to occur. In turn, the possibility that the sliding between the fixed valve body 14 and the driving valve body 22 will be hindered is reduced.

[0135] The modification of this embodiment in which the chamfering is eliminated and the outer peripheral surface 224 is connected to the sliding surface 220 and inclined at an acute angle to the sliding surface 140 can be applied not only to the outer peripheral surface 224 but also to the central inner peripheral surface 223 and the flow path inner peripheral surface 221. In this case, the same effect can be obtained.

[0136] In addition, a similar effect can be obtained by eliminating the chamfering and instead connecting the outer peripheral surface 144, the first flow path inner peripheral surface 141, the second flow path inner peripheral surface 142, and the central inner peripheral surface 146 to the sliding surface 140 and inclining them at an acute angle to the sliding surface 220.

[0137] The modifications of the fourth embodiment as in this embodiment are also applicable to the first to third embodiments. Furthermore, the same effects can be obtained from the same configurations of the other embodiments in this embodiment.

[0138] Sixth embodiment Next, a sixth embodiment will be described with reference to Figures 16 and 17. This embodiment differs from the first embodiment in the shape of the drive valve body 22. Other configurations are the same as those of the first embodiment.

[0139] In the driving valve body 22 of this embodiment, both the inclined surface X21 and the auxiliary surface X22 in the first embodiment are eliminated. In other words, chamfering is eliminated. Furthermore, the outer circumferential surface 224 and the sliding surface 220 are connected at a pin angle of approximately 90°.

[0140] As described in the first embodiment, there are gaps between the central inner peripheral surface 146 and the axial center portion 181 and between the central inner peripheral surface 223 and the axial center portion 181. Therefore, the positions of the fixed valve body 14 and the driven valve body 22 relative to the axial center portion 181 may change. For example, in a normal case, the outer peripheral surface 144 of the fixed valve body 14 protrudes outward in the radial direction DRr relative to the outer peripheral surface 224 of the driven valve body 22, as shown in FIG. 16. However, there are cases where a positional deviation occurs between the fixed valve body 14 and the driven valve body 22, and the outer peripheral surface 224 protrudes outward in the radial direction DRr relative to the outer peripheral surface 144, as shown in FIG.

[0141] Suppose that the valve device 10 is stopped in such a misaligned state and the cooling water is drained. In that case, if the inclined surface X11 is inclined at an acute angle with respect to the sliding surface 220 as shown in Fig. 17, a pool WS of the cooling water is likely to be formed in the space between the inclined surface X11 and the sliding surface 220 due to surface tension.

[0142] This liquid pool WS protects the vicinity of the edge of the sliding surface 140 on the outer circumferential surface 144 side. Therefore, even if the cooling water is drained when the position is misaligned, solidification of the remaining components between the sliding surface 140 and the sliding surface 220 is unlikely to occur. Furthermore, the possibility that the sliding between the fixed valve body 14 and the driven valve body 22 will be hindered is reduced.

[0143] As described above, since the inclination angle of the auxiliary surface X12 with respect to the sliding surface 220 is smaller than that of the inclined surface X11, the volume of the liquid pool WS can be made larger than when the auxiliary surface X12 is not present, and thus the evaporation of the liquid pool WS can be delayed. Also, since the opening of the gap formed between the inclined surface X11 and the auxiliary surface X12 and the sliding surface 220 becomes narrower, the evaporation of the liquid pool WS formed in this gap can be delayed.

[0144] In addition, although not shown, the first embodiment may be modified so that the inclined surface X23 and the auxiliary surface X24 are eliminated and the central inner circumferential surface 223 and the sliding surface 220 are connected at a substantially right angle. In this case, the valve device 10 may be stopped in a misaligned state in which the central inner circumferential surface 223 protrudes toward the axial center portion 181 more than the central inner circumferential surface 146, and the cooling water may be drained. In this case, if the inclined surface X13 is inclined at an acute angle with respect to the sliding surface 220, a pool of cooling water is likely to be formed in the space between the inclined surface X13 and the sliding surface 220 due to surface tension. In addition, as described above, since the inclination angle of the auxiliary surface X14 with respect to the sliding surface 220 is smaller than that of the inclined surface X13, the volume of the pool can be made larger than that in the case where the auxiliary surface X14 is not present, and the evaporation of the pool WS can be delayed. Furthermore, since the opening of the gap formed between the inclined surface X13 and the auxiliary surface X14 and the sliding surface 220 becomes narrower, the evaporation of the liquid pool formed in this gap can be delayed.

[0145] Moreover, the modifications of the first embodiment as in this embodiment are applicable to the other embodiments. Furthermore, the same effects can be obtained from the same configurations of the other embodiments as in the present embodiment.

[0146] (Other embodiments) The present invention is not limited to the above-described embodiment, and can be modified as appropriate. The above-described embodiments are not unrelated to each other, and can be combined as appropriate, except when the combination is clearly impossible. In the above-described embodiments, the elements constituting the embodiment are not necessarily essential, except when it is specifically stated that they are essential or when it is clearly considered essential in principle. In the above-described embodiments, when the numbers, values, amounts, ranges, etc. of the components of the embodiment are mentioned, they are not limited to the specific numbers, except when it is specifically stated that they are essential or when it is clearly limited to a specific number in principle. In particular, when multiple values ​​are exemplified for a certain amount, it is also possible to adopt a value between the multiple values, except when it is specifically stated otherwise or when it is clearly impossible in principle. In the above-described embodiments, when referring to the shape, positional relationship, etc. of the components, etc., they are not limited to the shape, positional relationship, etc., except when it is specifically stated or when it is limited to a specific shape, positional relationship, etc. in principle. In addition, the present invention also allows the following modifications and modifications within an equivalent range to the above-described embodiments. Note that the following modifications can be independently selected to be applied or not applied to the above-described embodiments. In other words, any combination of the following modifications can be applied to the above embodiment.

[0147] (Variation 1) In the above embodiment, cooling water containing water is exemplified as the liquid that flows through the flow path in the valve device 10 and has its flow path adjusted by the valve device 10. However, a liquid that does not contain water may be used, or a liquid for a purpose other than cooling water may be used.

[0148] (Variation 2) In the above embodiment, the valve device 10 is used in a vehicle and is mounted on the vehicle, but it does not necessarily have to be mounted on a vehicle.

[0149] (Variation 3) In the above embodiment, the valve device 10 is a three-way valve, but it may be a four-way or more valve. Alternatively, it may be a valve that simply adjusts the flow path of a liquid flow path rather than switching the liquid flow path.

[0150] (Variation 4) In the above embodiment, the fixed valve body 14 does not rotate, and the driven valve body 22 rotates, causing sliding between the sliding surfaces 140, 220. However, sliding between the sliding surfaces 140, 220 may also be caused by both the fixed valve body 14 and the driven valve body 22 rotating. [Explanation of symbols]

[0151] 10 Valve device 14 Fixed valve body 22 Drive valve body 140, 220 sliding surface X11, X13, X15, X21, X23 Slope X12, X14, X16, X22, X24 Auxiliary surface

Claims

1. A valve device for adjusting a flow rate of a liquid, which is a cooling water, in a vehicle, comprising: a first valve body (14) disposed in a first flow path (12d) through which the liquid flows; A second valve body (22) disposed in the first flow path, The surface of the first valve body has a first sliding surface (140) facing the second valve body, The surface of the second valve body has a second sliding surface (220) facing the first valve body, A degree of opening between the first flow path and the second flow path (12e) is changed by sliding between the first sliding surface and the second sliding surface, At least one of the first sliding surface and the second sliding surface has an edge portion connected to an inclined surface (X11, X13, X15, X21, X23, 224) inclined at an acute angle with respect to the mating sliding surface of the first sliding surface and the second sliding surface, Auxiliary surfaces (X11, X13, X15, X21, X23) are connected to the edge of the inclined surface on the opposite side to the at least one sliding surface, A valve device, wherein the auxiliary surface has an inclination angle with respect to the mating sliding surface smaller than that of the inclined surface.

2. The valve device according to claim 1 , wherein the inclined surface is a chamfer.

3. 2. The valve device according to claim 1, wherein the inclined surface is not a chamfer but is a part of a side surface (224) that is continuous with the at least one sliding surface and is continuous with a surface (229) opposite the at least one sliding surface.

4. A shaft (18) fixed to the second valve body; 4. The valve device according to claim 1, further comprising: a drive unit (16) having a stepping motor (161) for transmitting a rotational force to the shaft.

5. 5. The valve device according to claim 1, wherein the first valve body and the second valve body have a disk valve shape.

6. The second sliding surface slides against the first sliding surface by rotating around an axis (CL), 6. The valve device according to claim 1, wherein the inclined surface is continuous with an outer circumferential end of the at least one sliding surface, the outer circumferential end being centered on the axis.

7. 7. The valve device according to claim 1, wherein the first valve body and the second valve body are formed to contain ceramic.

8. 8. The valve device according to claim 1, wherein the liquid comprises water.

9. 9. The valve device according to claim 1, wherein the at least one sliding surface connected to the inclined surface is one of the first sliding surface and the second sliding surface, which has a smaller outer diameter.

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