Valve device and control device

Abstract

A valve device (1) comprises a housing (10, 20, 80, 88), a stationary valve (30, 97), a drive valve (40, 90), an actuator (50), and a control device (60). The control device (60) is capable of detecting a step-out position of a step motor (52) of the actuator (50). The control device (60) drives the step motor (52) with a torque that causes only the step motor (52) and a torque transmission mechanism (53) to rotate without causing the drive valve (40, 90) to rotate due to frictional force between the stationary valve (30, 97) and the drive valve (40, 90), and learns, as a backlash amount, the difference in rotation amount between a step-out position of the step motor (52) in a forward rotation direction and a step-out position in a reverse rotation direction.

Description

Valve and Control Devices CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on Japanese Patent Application No. 2024-049906, filed on March 26, 2024, the contents of which are incorporated herein by reference.

[0002] The present disclosure relates to a valve device that controls the flow of a fluid, and a control device that controls the actuation of the valve device.

[0003] The valve device described in Patent Document 1 includes a housing having a valve chamber and a fluid passage through which a fluid flows, a drive valve that rotates together with a shaft provided in the valve chamber, and an actuator that rotates the shaft and the drive valve. The actuator has a motor, a torque transmission mechanism that transmits torque output by the motor to the shaft, and a control device that controls the rotation of the motor. In this valve device, the control device drives the motor to rotate and controls the rotational position of the drive valve (hereinafter referred to as the "rotational position"), thereby adjusting the flow area of ​​the passage connecting the valve chamber and the fluid passage and controlling the flow rate of the fluid.

[0004] Japanese Patent Application Laid-Open No. 2022-166527

[0005] Generally, in a valve device, there is backlash (i.e., play) between parts such as gears provided in a torque transmission path through which torque is transmitted from the motor via the torque transmission mechanism to the shaft and the actuated valve. As a result, the amount of rotation of the actuated valve relative to the amount of rotation of the motor differs between the forward and reverse directions, making it difficult to move the actuated valve to the desired rotation position. Therefore, the valve device has a problem in that it is difficult to control the flow rate with high precision.

[0006] It is conceivable that during the manufacture of the valve device, additional equipment and processes could be added to identify the amount of backlash present in the torque transmission path for each individual product, and the identified amount of backlash could be used as a characteristic value for manufacturing variation and incorporated into the control device for each product on a one-to-one basis. This would allow the actuated valve to be moved to the target rotation position in accordance with the valve position command value by adding the amount of backlash as a correction value to the motor rotation amount corresponding to the valve position command value for the actuated valve. However, adding such equipment and processes would increase manufacturing costs.

[0007] An object of the present disclosure is to provide a valve device and a control device that are capable of highly accurate flow rate control.

[0008] According to one aspect of the present disclosure, a valve device for controlling the flow of a fluid comprises: a housing having a valve chamber through which the fluid flows and a fluid passage communicating with the valve chamber; a fixed valve fixed to the inside of the housing and having a hole communicating with the valve chamber and the fluid passage; a drive valve rotatable about a predetermined axis while in sliding contact with the fixed valve, and adjusting a flow passage area where the valve chamber and the fluid passage communicate with each other, or a flow passage area where a plurality of fluid passages communicate with each other; an actuator having a step motor and a torque transmission mechanism that transmits torque output by the step motor to a member connected to the drive valve or to the drive valve, and rotating the drive valve; and a control device that is capable of detecting an out-of-step position where the step motor loses control because the amount of rotation of the step motor does not reach a motor rotation amount command value commanded to the step motor, and drives the step motor with a torque that rotates only the step motor and the torque transmission mechanism without rotating the drive valve due to frictional force between the fixed valve and the drive valve, and learns the difference in rotation amount between the out-of-step position in the forward rotation direction of the step motor and the out-of-step position in the reverse rotation direction of the step motor as the amount of backlash.

[0009] This allows the control device to learn the amount of backlash present in the torque transmission path, through which torque is transmitted from the step motor via the torque transmission mechanism to the actuated valve, taking into account not only the design value but also the manufacturing variability of each product. Therefore, the control device can move the actuated valve to the target rotation position in accordance with the valve position command value by adding a correction value for the backlash that corresponds to each product to the rotation amount of the step motor corresponding to the valve position command value for the actuated valve. Therefore, this valve device can achieve highly accurate flow control. Furthermore, since this valve device does not require additional equipment or processes during valve device manufacturing to determine the amount of backlash present in the torque transmission path for each product, it is possible to prevent increases in manufacturing costs.

[0010] According to another aspect of the present disclosure, a valve device for controlling a flow of a fluid includes a housing having a valve chamber through which the fluid flows and a fluid passage communicating with the valve chamber; a fixed valve fixed to the inside of the housing and having a hole communicating with the valve chamber and the fluid passage; a drive valve rotatable about a predetermined axis while making sliding contact with the fixed valve, and adjusting a flow path area connecting the valve chamber and the fluid passage or a flow path area connecting a plurality of fluid passages together; an actuator having an electric motor and a torque transmission mechanism that transmits torque output by the electric motor to a member connected to the drive valve or to the drive valve, and rotates the drive valve; a position detection sensor that detects the rotational position of the electric motor or the torque transmission mechanism; and a control device that drives the electric motor with a torque that rotates only the electric motor and the torque transmission mechanism, without rotating the drive valve due to friction between the fixed valve and the drive valve, and learns the difference in rotation amount between a stop position in the forward rotation direction and a stop position in the reverse rotation direction of the electric motor or the torque transmission mechanism, detected by the position detection sensor, as an amount of backlash.

[0011] According to this, the valve device can achieve the same effect as the one aspect of the present disclosure described above even when a general electric motor is used as the actuator, without using a step motor.

[0012] According to yet another aspect of the present disclosure, a control device for controlling the drive of a valve device including: a housing having a valve chamber through which a fluid flows and a fluid passage communicating with the valve chamber; a fixed valve fixed to the inside of the housing and having a hole communicating with the valve chamber and the fluid passage; a drive valve rotatable about a predetermined axis while in sliding contact with the fixed valve, and adjusting the flow path area where the valve chamber and the fluid passage communicate with each other, or the flow path area where a plurality of fluid passages communicate with each other; and an actuator having a step motor and a torque transmission mechanism that transmits the torque output by the step motor to a member connected to the drive valve or to the drive valve, and rotating the drive valve, is capable of detecting an out-of-step position where the step motor loses control because the amount of rotation of the step motor does not reach a motor rotation amount command value commanded to the step motor, and drives the step motor with a torque that rotates only the step motor and the torque transmission mechanism without causing the drive valve to rotate due to frictional force between the fixed valve and the drive valve, and learns the difference in the amount of rotation between the out-of-step position in the forward rotation direction of the step motor and the out-of-step position in the reverse rotation direction of the step motor as the amount of backlash.

[0013] According to this, the control device that controls the actuation of the valve device can achieve the same effect as the above-described one aspect of the present disclosure.

[0014] According to yet another aspect of the present disclosure, a control device for controlling the drive of a valve device comprising: a housing having a valve chamber through which fluid flows and a fluid passage communicating with the valve chamber; a fixed valve fixed to the inside of the housing and having a hole communicating with the valve chamber and the fluid passage; a drive valve that is rotatable about a predetermined axis while making sliding contact with the fixed valve and adjusts the flow path area where the valve chamber and the fluid passage communicate with each other, or the flow path area where a plurality of fluid passages communicate with each other; an actuator that has an electric motor and a torque transmission mechanism that transmits torque output by the electric motor to a member connected to the drive valve or to the drive valve, and rotates the drive valve; and a position detection sensor that detects the rotational position of the electric motor or the torque transmission mechanism, drives the electric motor with a torque that rotates only the electric motor and the torque transmission mechanism, without rotating the drive valve due to friction between the fixed valve and the drive valve, and learns the difference in rotation amount between the stop position in the forward rotation direction and the stop position in the reverse rotation direction of the electric motor or the torque transmission mechanism, detected by the position detection sensor, as the amount of backlash.

[0015] According to this, the control device that controls the actuation of the valve device can achieve the same effect as the above-described one aspect of the present disclosure.

[0016] 1 is a perspective view of a valve device according to a first embodiment; FIG. 2 is a cross-sectional view of the valve device according to the first embodiment; FIG. 3 is a cross-sectional view taken along line III-III in FIG. 2; FIG. 4 is a view in which the shape of the sliding surface side of the actuated valve is superimposed on the cross-sectional view taken along line IV-IV in FIG. 2; FIG. 5 is a perspective view of a holder, a lever, a torsion spring, an actuated valve, a shaft, and a fixed valve; FIG. 6 is a perspective view showing a state in which the rotational position of the actuated valve is changed in section VI in FIG. 2; FIG. 7 is a perspective view including a partial cross-section of an actuator; FIG. 8 is an explanatory view showing a meshing state between an output gear of a torque transmission mechanism and a gear of a holder in a forward rotation direction; FIG. 9 is an explanatory view showing a meshing state between an output gear of a torque transmission mechanism and a gear of a holder in a reverse rotation direction; FIG. 10 is a graph showing the relationship between the current supplied to a step motor and the torque generated by the actuator; FIG. 11 is a graph showing the relationship between a motor rotation amount command value commanded to the step motor when a control device executes backlash amount learning and the actual rotation amount of the step motor; FIG. 12 is a perspective view including a partial cross-section of an actuator included in a valve device according to a second embodiment; FIG. 13 is a perspective view including a partial cross-section of an actuator included in a valve device according to a third embodiment; FIG. 14 is an exploded perspective view of a valve device according to a fourth embodiment; FIG. 15 is a cross-sectional view perpendicular to the axis of the valve device according to the fourth embodiment.

[0017] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the following embodiments, identical or equivalent parts will be denoted by the same reference numerals, and description thereof will be omitted.

[0018] (First Embodiment) A valve device 1 according to the first embodiment is used in a fluid circulation system mounted on, for example, an electric vehicle or a hybrid vehicle. The fluid circulation system circulates coolant fluid through vehicle components such as a power source for driving the vehicle, a radiator, and a heater core for cabin air conditioning. For example, LLC (Long Life Coolant) containing ethylene glycol is used as the coolant. The valve device 1 constitutes part of the fluid circulation system and switches the flow path of the coolant flowing through the system and adjusts the flow rate.

[0019] First, a description will be given of the configuration of the valve device 1. As shown in Figures 1 and 2, the valve device 1 is a disc valve including housings 10 and 20, a fixed valve 30, a drive valve 40, an actuator 50, and the like.

[0020] In the following description, the direction extending from the axis CL of rotation of the actuated valve 40 in the radial direction of an imaginary circle that is perpendicular to the axis CL and centered on the axis CL will be referred to as the "radially outward direction," and the direction toward the axis CL will be referred to as the "radially inward direction." The direction in which the axis CL extends will be referred to as the "axial direction," and the side of the housings 10, 20 on which the actuator 50 is provided will be referred to as the "one axial side," and the opposite side will be referred to as the "other axial side."

[0021] The housings 10, 20 are composed of a first housing 10 and a second housing 20, and have a flow path inside them through which a fluid flows. The first housing 10 has a flow path forming portion 11 formed in a cylindrical shape, fluid inlet portions 12, 13 extending from the flow path forming portion 11 in a pipe-like shape, and three fluid outlet portions 14, 15, 16.

[0022] The fluid inlet portions 12, 13 include a first fluid inlet portion 12 and a second fluid inlet portion 13. A first fluid inlet passage 102 is formed inside the first fluid inlet portion 12, and a second fluid inlet passage 103 is formed inside the second fluid inlet portion 13.

[0023] 1 to 4, the three fluid outlets 14, 15, 16 include a first fluid outlet 14, a second fluid outlet 15, and a third fluid outlet 16. A first fluid outlet passage 104 is formed inside the first fluid outlet 14, a second fluid outlet passage 105 is formed inside the second fluid outlet 15, and a third fluid outlet passage 106 is formed inside the third fluid outlet 16.

[0024] The flow path forming portion 11 of the first housing 10 has a valve chamber 100 through which fluid flows, in a region on the drive valve 40 side of the fixed valve 30. The drive valve 40 and other components are provided in the valve chamber 100. A second fluid inlet passage 103 on the inner side of the second fluid inlet portion 13 extends radially outward from the valve chamber 100 of the flow path forming portion 11.

[0025] 2 and 3, the flow path forming portion 11 of the first housing 10 has, in an area on the opposite side of the fixed valve 30 from the actuated valve 40, a plurality of inner passages 110 and a plurality of outer passages 120 as fluid passages leading to the valve chamber 100. The flow path forming portion 11 also has, as structural components in that area, a support portion 170, an inner passage partition wall 160, an inner / outer passage partition wall 130, an outer passage partition wall 140, and an outer peripheral wall 150.

[0026] The support portion 170 rotatably supports the end portion 78 of the shaft 70 that is inserted through the insertion hole 47 of the drive valve 40 and the central hole 39 of the fixed valve 30 (i.e., the end portion 78 on the other side of the axial direction of the shaft 70).

[0027] The multiple inner passages 110 are passages formed in a region radially outside the support portion 170. The multiple inner passages 110 are arranged within a predetermined angular range in the circumferential direction of the first housing 10 so as to surround the radially outside of the support portion 170. All of the multiple inner passages 110 are connected to a first fluid inlet passage 102 inside the first fluid inlet portion 12. The first fluid inlet passage 102 extends from the multiple inner passages 110 to the other side in the axial direction.

[0028] The inner passage partition wall 160 is a wall that separates the multiple inner passages 110 from one another, and radially connects the support portion 170 and the inner / outer passage partition wall 130. The inner / outer passage partition wall 130 is a wall that separates the inner passages 110 from the outer passage 120, and is provided in a cylindrical shape between the inner passages 110 and the outer passage 120.

[0029] The multiple outer passages 120 are formed radially outward from the multiple inner passages 110. The multiple outer passages 120 include a first outer passage 121, a second outer passage 122, and a third outer passage 123. The first outer passage 121, the second outer passage 122, and the third outer passage 123 are arranged within a predetermined angular range in the circumferential direction of the first housing 10 so as to surround the radially outer sides of the multiple inner passages 110.

[0030] The first outer passage 121 is in communication with the first fluid outlet passage 104 inside the first fluid outlet portion 14. The first fluid outlet passage 104 extends radially outward from the first outer passage 121. The second outer passage 122 is in communication with the second fluid outlet passage 105 inside the second fluid outlet portion 15. The second fluid outlet passage 105 extends radially outward from the second outer passage 122. The third outer passage 123 is in communication with the third fluid outlet passage 106 inside the third fluid outlet portion 16. The third fluid outlet passage 106 extends radially outward from the third outer passage 123.

[0031] The outer passage partition wall 140 is a wall that separates the first outer passage 121, the second outer passage 122, and the third outer passage 123, and radially connects the inner / outer passage partition wall 130 and the outer peripheral wall 150. The outer peripheral wall 150 is a wall that forms the outer contour of the flow path forming portion 11, and is provided in a cylindrical shape radially outside the outer passage 120.

[0032] 2 , the fixed valve 30 is provided at the boundary between the inner passage 110, the outer passage 120, and the valve chamber 100. The fixed valve 30 is formed in a generally disk shape and is placed on one axial end of the outer peripheral wall 150, the outer passage partition wall 140, the inner / outer passage partition wall 130, the inner passage partition wall 160, and the support portion 170 of the first housing 10. Note that a seal member 19 is provided between the fixed valve 30 and the valve chamber 100-side ends of the outer peripheral wall 150, the outer passage partition wall 140, the inner / outer passage partition wall 130, the inner passage partition wall 160, and the support portion 170.

[0033] 2, 4, and 5, the fixed valve 30 has a plurality of inner holes 36 and a plurality of outer holes 34 that communicate with the fluid passages (i.e., the inner passage 110 and the outer passage 120) and the valve chamber 100. The fixed valve 30 also has, as structural components, a central portion 33, an inner hole partitioning portion 37, a middle partitioning portion 32, an outer hole partitioning portion 35, an outer peripheral portion 31, and a protrusion 38. The protrusion 38 on the outer peripheral portion 31 is engaged with a locking portion 17 provided on the first housing 10. This fixes the fixed valve 30 so that it does not rotate relative to the flow path forming portion 11 around the axis CL.

[0034] The other axial end 78 of the shaft 70 is inserted into a central hole 39 provided in the central portion 33. The multiple inner holes 36 are connected to multiple inner passages 110, respectively. The multiple outer holes 34 include a first outer hole 34a, a second outer hole 34b, a third outer hole 34c, and a fourth outer hole 34d. The first outer hole 34a is connected to a first outer passage 121. The second outer hole 34b and the fourth outer hole 34d are connected to a second outer passage 122. The third outer hole 34c is connected to a third outer passage 123.

[0035] The central portion 33 is a portion that surrounds the periphery of the central hole 39 and is placed on the support portion 170. The inner hole partition portion 37 is a portion that radially separates the multiple inner holes 36 and is placed on the inner passage partition wall 160. The intermediate partition portion 32 is a portion that circumferentially separates the inner holes 36 and the outer holes 34 and is placed on the inner-outer passage partition wall 130. The outer hole partition portion 35 is a portion that radially separates the multiple outer holes 34 and is placed on the outer passage partition wall 140. The outer peripheral portion 31 is a portion that is formed in an annular shape radially outside the multiple outer holes 34 and is placed on the outer peripheral wall 150.

[0036] As shown in FIGS. 1 and 2 , the second housing 20 closes an opening on one axial side of the valve chamber 100 of the first housing 10 , and forms the valve chamber 100 together with the first housing 10 .

[0037] 2, 4, 5, and 6, the actuated valve 40 is formed in a generally disk shape and is provided in the valve chamber 100 so as to be rotatable about the axis CL of the shaft 70. The surface of the actuated valve 40 facing the other side in the axial direction (i.e., the surface facing the fixed valve 30) is called the sliding surface 41. The sliding surface 41 of the actuated valve 40 and the fixed valve 30 are in sliding contact with each other. That is, the actuated valve 40 is in sliding contact with the fixed valve 30.

[0038] The actuated valve 40 has a groove 42 recessed from the sliding contact surface 41 toward one side in the axial direction, and a through-hole 43 penetrating in the axial direction. A shaft 70 is inserted into an insertion hole 47 on the inside of a cylindrical portion 46 provided inside the groove 42. For the sake of explanation, in FIG. 4 , the shapes of the groove 42 and through-hole 43 of the actuated valve 40 are depicted larger than the inner hole 36 and outer hole 34 of the fixed valve 30. However, in reality, the shapes of the groove 42 and through-hole 43 of the actuated valve 40 may be the same as the shapes of the inner hole 36 and outer hole 34 of the fixed valve 30.

[0039] The groove 42 is provided so as to communicate with the multiple inner holes 36 and a specific outer hole 34 when the actuated valve 40 is in a specific rotational position. By controlling the rotational position of the actuated valve 40, it is possible to adjust the flow path area through which the groove 42 communicates with a specific outer hole 34 (i.e., a specific outer passage 120). In other words, the actuated valve 40 is able to adjust the flow path area through which the multiple inner passages 110 communicate with a specific outer passage 120 via the groove 42.

[0040] Furthermore, the through hole 43 is provided so as to communicate between the valve chamber 100 and a predetermined outer hole 34 when the actuated valve 40 is at a predetermined rotational position. By controlling the rotational position of the actuated valve 40, it is possible to adjust the flow path area through which the through hole 43 communicates with the predetermined outer hole 34 (i.e., the predetermined outer passage 120). In other words, the actuated valve 40 is able to adjust the flow path area through which the valve chamber 100 communicates with the predetermined outer passage 120 via the through hole 43.

[0041] 6 , when the actuated valve 40 is in a predetermined rotational position, as indicated by arrow LF1, fluid flowing in from the first fluid inlet passage 102 flows in the following order: inner passage 110 → the plurality of inner holes 36 → the groove 42 → the first outer hole 34a → the first outer passage 121 → the first fluid outlet passage 104. Although not shown, the control device 60 can adjust the flow path area connecting the groove 42 and the first outer hole 34a, i.e., the flow path area connecting the inner passage 110 and the first outer passage 121, by controlling the rotational position of the actuated valve 40. This allows the control device 60 to adjust the flow rate of fluid flowing from the first fluid inlet passage 102 to the first fluid outlet passage 104.

[0042] 6 , when the actuated valve 40 is in a predetermined rotational position, the fluid that flows in from the second fluid inlet passage 103 flows in the following order: valve chamber 100 → through hole 43 → second outer hole 34b → second outer passage 122 → second fluid outlet passage 105. Although not shown, the control device 60 can adjust the flow path area through which the through hole 43 and the second outer hole 34b communicate, i.e., the flow path area through which the valve chamber 100 communicates with the second outer passage 122, by controlling the rotational position of the actuated valve 40. This allows the control device 60 to adjust the flow rate of the fluid flowing from the second fluid inlet passage 103 to the second fluid outlet passage 105.

[0043] 2, the shaft 70 is provided inside the first housing 10 and the second housing 20. The shaft 70 passes through the insertion hole 47 of the drive valve 40 and the central hole 39 of the fixed valve 30. An end 78 on the other axial side of the shaft 70 is rotatably supported in a bearing hole 171 of a support portion 170.

[0044] A holder 71 is fixed to one axial side of the shaft 70. The shaft 70 and holder 71 are integrally formed by, for example, insert molding. The holder 71 is rotatably supported by a bearing 72 provided in the second housing 20. An annular seal member 77 is provided between the outer wall of the holder 71 and the inner wall of the second housing 20 at a location on the other axial side of the bearing 72 (i.e., on the valve chamber 100 side). This annular seal member 77 prevents fluid from leaking from the valve chamber 100 toward the bearing 72.

[0045] 2, 5, and 7, a holder-side gear 73 provided on one axial side of the holder 71 meshes with the output gear 58 of the torque transmission mechanism 53 of the actuator 50. A lever 74 is provided between the holder 71 and the actuated valve 40. The lever 74 connects the holder 71 and the actuated valve 40 in the rotational direction. Therefore, the torque output by the actuator 50 is transmitted from the holder 71 to the actuated valve 40 via the lever 74.

[0046] A compression spring 75 and a torsion spring 76 are provided between the holder 71 and the lever 74. One end of the compression spring 75 is engaged with the holder 71, and the other end is engaged with the lever 74. The compression spring 75 presses the lever 74, the actuated valve 40, the fixed valve 30, and the seal member 19 against the holder 71, pressing the lever 74, the actuated valve 40, the fixed valve 30, and the seal member 19 toward the surface of the first housing 10 facing the fixed valve 30. The surface of the first housing 10 facing the fixed valve 30 refers to the end faces of the support portion 170, the inner passage partition wall 160, the inner / outer passage partition wall 130, the outer passage partition wall 140, and the outer peripheral wall 150 on one axial side (i.e., the surface on which the seal member 19 is provided). A reaction force against the pressing force of the compression spring 75 acts on the fixed valve 30 from the surface of the first housing 10 facing the fixed valve 30 and the seal member 19. As a result, frictional force is generated between the actuated valve 40 and the fixed valve 30. Therefore, the compression spring 75 is a member that generates a frictional force between the drive valve 40 and the fixed valve 30. By adjusting the load of the compression spring 75, the frictional force between the drive valve 40 and the fixed valve 30 can be adjusted.

[0047] One end of the torsion spring 76 is engaged with the holder 71, and the other end is engaged with the lever 74, and presses the lever 74 and the drive valve 40 in the rotational direction against the holder 71. Therefore, there is no play in the rotational direction between the holder 71 and the lever 74.

[0048] The actuator 50 is provided on the opposite side of the second housing 20 from the first housing 10. As shown in Fig. 7, the actuator 50 includes a step motor 52, a torque transmission mechanism 53, and a control device 60 housed within a case 51. The amount of rotation (i.e., the rotation angle) of the step motor 52 is controlled by the control device 60. That is, the step motor 52 rotates an amount of rotation corresponding to a motor rotation amount command value issued by the control device 60.

[0049] The torque transmission mechanism 53 transmits the torque output by the step motor 52 to the holder 71. The holder 71 is an example of a "member connected to the actuated valve 40." Specifically, the torque output by the step motor 52 is transmitted from the step motor 52 to the torque transmission mechanism 53, the holder 71, the shaft 70 and the lever 74, and then to the actuated valve 40. The holder 71, the shaft 70, the compression spring 75, the torsion spring 76, the lever 74, and the actuated valve 40 rotate as a unit.

[0050] The torque transmission mechanism 53 is a reduction mechanism having a first gear 55, a second gear 56, a third gear 57, and an output gear 58. The first gear 55 is a worm gear fixed to the rotation shaft of the step motor 52. The second gear 56 has a second large-diameter gear 56a and a second small-diameter gear 56b. The third gear 57 has a third large-diameter gear 57a and a third small-diameter gear 57b. The output gear 58 has an output large-diameter gear 58a and an internal gear 58b shown in FIGS. 8 and 9.

[0051] As shown in Fig. 7, the first gear 55 meshes with the second large-diameter gear 56a of the second gear 56. The second small-diameter gear 56b of the second gear 56 meshes with the third large-diameter gear 57a of the third gear 57. The third small-diameter gear 57b of the third gear 57 meshes with the output large-diameter gear 58a of the output gear 58. As shown in Figs. 8 and 9, the internal gear 58b of the output gear 58 meshes with a holder-side gear 73 provided on one axial side of the holder 71. Note that backlash, i.e., play, exists between the meshing gears of the first gear 55, second gear 56, third gear 57, output gear 58, and holder-side gear 73.

[0052] FIG. 8 shows a state in which the internal gear 58b of the output gear 58 rotates the holder-side gear 73 in the clockwise direction indicated by the arrow CW. FIG. 9 shows a state in which the internal gear 58b of the output gear 58 rotates the holder-side gear 73 in the counterclockwise direction indicated by the arrow CCW. In the following description, the direction in which the step motor 52, the torque transmission mechanism 53, etc. rotate in the direction indicated by the arrow CW in FIG. 8 is referred to as the "forward rotation direction," and the direction in which they rotate in the direction indicated by the arrow CCW in FIG. 9 is referred to as the "reverse rotation direction." As shown in FIGS. 8 and 9, backlash, i.e., play, also exists between the internal gear 58b of the output gear 58 and the holder-side gear 73. Therefore, the amount of rotation of the output gear 58 and the amount of rotation of the holder-side gear 73 differ between the forward rotation direction and the reverse rotation direction. As described above, backlash, i.e., play, exists among the first gear 55, the second gear 56, the third gear 57, and the output gear 58. Therefore, the amount of rotation of the drive valve 40 relative to the amount of rotation of the step motor 52 differs between the forward rotation direction and the reverse rotation direction.

[0053] 7, in the first embodiment, the control device 60 is configured on a circuit board 65 provided inside the case 51 of the actuator 50. The control device 60 is not limited to this configuration, and may be incorporated into, for example, a system ECU 61 that is provided separately from the valve device 1 and controls the operation of the entire fluid circulation system. ECU is an abbreviation for Electronic Control Unit.

[0054] The control device 60 is composed of a microcomputer including a processor that performs control processing and arithmetic processing, a storage unit such as ROM and RAM that stores programs, data, etc., and its peripheral circuits. In the control device 60, the processor performs various control processing and arithmetic processing based on the programs stored in the storage unit.

[0055] The control device 60 drives the step motor 52 in accordance with the rotational position of the actuated valve 40 (hereinafter referred to as the "valve position command value") based on a request from the vehicle-side ECU 62, and moves the actuated valve 40 to a rotational position consistent with the valve position command value. Specifically, the control device 60 generates a motor rotation amount command value in accordance with the valve position command value, and supplies pulses to the step motor 52 so that the rotation amount of the step motor 52 becomes the motor rotation amount command value.

[0056] As described above, there is backlash in the torque transmission path through which torque is transmitted from the step motor 52 to the actuated valve 40 via the torque transmission mechanism 53 and the like. Therefore, the amount of rotation of the actuated valve 40 relative to the amount of rotation of the step motor 52 differs between the forward rotation direction and the reverse rotation direction. Therefore, the control device 60 of this embodiment is configured to drive the step motor 52 by adding the amount of backlash present in the torque transmission path as a correction value to the motor rotation amount command value corresponding to the valve opening command value.

[0057] In detail, when the control device 60 drives the step motor 52 or the like in the forward rotation direction and then in the reverse rotation direction, the control device 60 adds the amount of backlash present in the torque transmission path as a correction value to the motor rotation amount command value corresponding to the valve position command value, and drives the step motor 52. Furthermore, when the control device 60 drives the step motor 52 or the like in the forward rotation direction and then in the reverse rotation direction, the control device 60 adds the amount of backlash present in the torque transmission path as a correction value to the motor rotation amount command value corresponding to the valve position command value, and drives the step motor 52.

[0058] Next, a method for the control device 60 of this embodiment to learn the amount of backlash present in the torque transmission path will be described. Hereinafter, learning the amount of backlash present in the torque transmission path will be referred to as "backlash amount learning."

[0059] The horizontal axis of the graph in Fig. 10 represents the current value supplied to the step motor 52 (hereinafter referred to as "motor supply current"), and the vertical axis represents the torque with which the actuator 50 rotates the drive valve 40 (hereinafter referred to as "actuator generated torque"). As indicated by the solid line AC in the graph in Fig. 10, the relationship between the motor supply current and the actuator generated torque is linear.

[0060] μ in FIG. １ From μ ３ The range of μ indicates the range of frictional force (specifically, static frictional force) generated between the drive valve 40 and the fixed valve 30 due to the pressing force of the compression spring 75. Note that this frictional force is within a predetermined range depending on individual product variations, the usage environment, and aging. Here, the frictional force of a certain product is expressed as μ ２ At this time, the torque generated by the actuator is equal to the friction force μ ２ If it is smaller, the actuated valve 40 will remain stopped and the actuator-generated torque will be ２ If it is greater, the actuated valve 40 will be rotationally actuated.

[0061] The control device 60 controls the torque generated by the actuator so as to be lower than the lower limit value μ １ Therefore, the control device 60 sets the torque smaller than the lower limit value μ of the range of the frictional force, and executes the backlash amount learning. １ The control device 60 supplies the step motor 52 with a motor supply current that makes the actuator torque smaller than I. Specifically, the control device 60 performs backlash amount learning. １ The control device 60 then supplies a motor supply current to the step motor 52 that is smaller than the torque required to rotate the actuated valve 40, thereby enabling the control device 60 to drive the step motor 52 with a torque that rotates only the step motor 52 and the torque transmission mechanism 53, without causing the actuated valve 40 to rotate, thereby enabling the control device 60 to perform backlash learning.

[0062] 11 shows the relationship between the motor rotation amount command value given to the step motor 52 when the control device 60 learns the amount of backlash and the actual amount of rotation of the step motor 52. The horizontal axis of FIG. 11 represents time, and the vertical axis represents the motor rotation amount command value given to the step motor 52 by the control device 60 and the amount of rotation of the step motor 52. The dashed-dotted line P in FIG. 11 represents the motor rotation amount command value given to the step motor 52 by the control device 60, and the solid line Q represents the actual amount of rotation of the step motor 52. For the sake of explanation, the dashed-dotted line P and the solid line Q are shown slightly offset from each other between times t0 and t2 and between t5 and t6 in FIG. 11, but in reality, the dashed-dotted line P and the solid line Q are substantially aligned.

[0063] The control device 60 performs the backlash amount learning shown in Fig. 11 after the power supply to the fluid circulation system is turned off, for example. Alternatively, the control device 60 performs the backlash amount learning shown in Fig. 11 immediately after the power supply to the fluid circulation system is turned on, for example.

[0064] The control device 60 begins learning the amount of backlash at time t1 and outputs a motor rotation amount command value that rotates the step motor 52 in the forward direction from time t1 to time t3. At this time, the actual rotation amount of the step motor 52 gradually increases in the forward direction from time t1 to time t2 in accordance with the motor rotation amount command value. However, at time t2, the rotation of the step motor 52 stops due to frictional force generated between the drive valve 40 and the fixed valve 30. In other words, the step motor 52 loses synchronization at time t2. Note that "loss of synchronization" refers to the state in which the rotation amount of the step motor 52 does not reach the motor rotation amount command value and the rotation of the step motor 52 stops. The control device 60 detects the position at which the step motor 52 loses synchronization (hereinafter referred to as the "out-of-synchronization position"), for example, by fluctuations in the back electromotive force generated in the motor coil.

[0065] Next, the control device 60 outputs a motor rotation amount command value that rotates the step motor 52 in the reverse direction from time t4 to time t7. At this time, the actual rotation amount of the step motor 52 gradually increases in the reverse direction in accordance with the motor rotation amount command value from time t5 to time t6. However, at time t6, the rotation of the step motor 52 stops due to the frictional force generated between the drive valve 40 and the fixed valve 30. In other words, the step motor 52 loses synchronization at time t6. The control device 60 detects the loss-of-synchronization position, for example, from fluctuations in the back electromotive force generated in the motor coil.

[0066] Next, the control device 60 calculates the difference in rotation amount between the step-out position in the forward rotation direction of the step motor 52 detected at time t2 and the step-out position in the reverse rotation direction of the step motor 52 detected at time t6 (i.e., R ４ -R ２ ) is calculated. The control device 60 then learns the calculated difference as the amount of backlash present in the torque transmission path. The control device 60 stores the learned amount of backlash in its own non-volatile memory. The control device 60 then adds the learned amount of backlash as a correction value to the motor rotation amount command value corresponding to the valve opening command value, and drives the step motor 52.

[0067] The valve device 1 of the first embodiment described above provides the following advantages.

[0068] (1) The control device 60 included in the valve device 1 of the first embodiment can detect the out-of-step position of the step motor 52. In learning the amount of backlash, the control device 60 drives the step motor 52 with a torque that rotates only the step motor 52 and the torque transmission mechanism 53, without rotating the drive valve 40 due to friction between the fixed valve 30 and the drive valve 40. The control device 60 then learns the difference in rotation amount between the out-of-step position in the forward rotation direction of the step motor 52 and the out-of-step position in the reverse rotation direction of the step motor 52 as the amount of backlash. This allows the control device 60 to learn the amount of backlash present in the torque transmission path, taking into account not only the design value but also the manufacturing variations of each product. Therefore, the control device 60 adds a correction value for the amount of backlash specific to each product to the rotation amount of the step motor 52 corresponding to the valve position command value, and then drives the step motor 52 to rotate the drive valve 40. This allows the drive valve 40 to move to the target rotation position consistent with the valve position command value. Therefore, the valve device 1 can achieve highly accurate flow control. Furthermore, since this valve device 1 does not require additional equipment or processes during the manufacture of the valve device 1 in order to determine the amount of backlash present in the torque transmission path for each individual product, an increase in manufacturing costs can be prevented.

[0069] (2) In the first embodiment, the control device 60 adds the amount of backlash as a correction value to the amount of rotation of the step motor 52 corresponding to the valve position command value based on a request from the vehicle-side ECU 62, and then drives the step motor 52 to rotate. This allows the control device 60 to cancel the amount of backlash that is specific to each product and move the actuated valve 40 to the target position in accordance with the valve position command value, thereby achieving highly accurate flow rate control.

[0070] (3) In the first embodiment, the control device 60 may store in advance in its memory a predetermined threshold value that defines a normal range for the amount of backlash in terms of design. The control device 60 may be configured to determine that an abnormal state has occurred when the amount of backlash exceeds the predetermined threshold value. In this way, when the amount of backlash present in the torque transmission path of the valve device 1 is greater than expected at the time of design, an abnormality signal is issued, and the user can be prompted to replace parts of the valve device 1.

[0071] (4) In the first embodiment, the control device 60 adjusts the torque output by the step motor 52 when learning the amount of backlash by supplying to the step motor 52 a current value that is smaller than the current value that is supplied to the step motor 52 when rotating the drive valve 40. In this way, the torque output by the step motor 52 is adjusted by reducing the current value supplied to the step motor 52, and the amount of backlash can be learned.

[0072] (5) Incidentally, it is considered that the frictional force between the drive valve 40 and the fixed valve 30 of the valve device 1 may change due to the usage environment, aging, etc. To cope with such a phenomenon, the control device 60 can find the current value to be supplied to the step motor 52 when learning the backlash amount by the following method. As shown in FIG. 10 , the control device 60 calculates the current value when the torque generated by the actuator is equal to the upper limit value μ of the range of the frictional force. ３ The motor supply current (e.g., I ４ ) is supplied to the step motor 52, and the motor supply current is gradually reduced. Then, as the motor supply current decreases, the actuator generated torque decreases to a predetermined friction force (for example, μ １ ), the step motor 52 will step out (in other words, the step motor 52 will stop rotating) due to the frictional force. For this reason, the control device 60 calculates the current value (for example, I １ ) can be set as the current value supplied to the step motor 52 when learning the amount of backlash. In this way, even if the frictional force between the drive valve 40 and the fixed valve 30 changes due to the usage environment or aging, the control device 60 can find the current value for learning the amount of backlash and can perform the backlash learning.

[0073] (6) In the first embodiment, the control device 60 can learn the amount of backlash after the power supply to the fluid circulation system is turned off. This allows the control device 60 to detect the out-of-step positions in the forward and reverse rotation directions of the step motor 52 after the power supply to the fluid circulation system is turned off, i.e., after the request from the vehicle ECU 62 is no longer received, thereby preventing a loss of usability for the user.

[0074] (7) In the first embodiment, the control device 60 records the learned amount of backlash in its own nonvolatile memory. This allows the learned amount of backlash to be retained even after the fluid circulation system is turned off, and the previously learned amount of backlash can be used the next time the system is started, thereby enabling high-precision flow rate control to be quickly performed.

[0075] (8) In the first embodiment, the control device 60 can learn the amount of backlash immediately after the power supply to the fluid circulation system is turned on. This allows for highly accurate flow control, even if the amount of backlash fluctuates while the vehicle or the fluid circulation system is stopped, by using a highly reliable learned value of the amount of backlash that excludes the fluctuation.

[0076] (9) In the first embodiment, the control device 60 may be configured to be able to acquire the outside air temperature outside the vehicle cabin, the temperature of the fluid flowing through the valve device 1 in the fluid circulation system, or the temperature inside the actuator 50. In this case, the control device 60 adds a value obtained by correcting the amount of backlash based on the acquired temperature information as a correction value to the rotation amount of the step motor 52 corresponding to the valve opening command value, and drives the step motor 52 to rotate. In this way, by correcting the amount of backlash based on the acquired temperature information, more accurate flow rate control can be achieved.

[0077] (10) The valve device 1 of the first embodiment includes a compression spring 75. The compression spring 75 is a member that presses the drive valve 40 against the fixed valve 30, generating a frictional force between the drive valve 40 and the fixed valve 30. This makes it possible to easily adjust the frictional force between the fixed valve 30 and the drive valve 40 by adjusting the load of the compression spring 75.

[0078] Second Embodiment A second embodiment will be described. The second embodiment is similar to the first embodiment except for the configuration of the actuator 50, and therefore only the differences from the first embodiment will be described.

[0079] 12 , the actuator 50 provided in the valve device 1 of the second embodiment has, within a case 51, an electric motor 54, a position detection sensor 59, a torque transmission mechanism 53, and a control device 60. The rotation of the electric motor 54 is controlled by the control device 60. The position detection sensor 59 detects the rotational position of the torque transmission mechanism 53. Specifically, the position detection sensor 59 detects, for example, the rotational position of an output gear 58. Information detected by the position detection sensor 59 is transmitted to the control device 60.

[0080] The control device 60 drives the electric motor 54 in accordance with a valve position command value based on a request from the vehicle-side ECU 62, and moves the actuated valve 40 to a rotational position according to the valve position command value. For example, the control device 60 performs feedback control or feedforward control of the power supply to the electric motor 54 based on information detected by the position detection sensor 59 so that the actuated valve 40 moves to a rotational position according to the valve position command value.

[0081] As described above, there is backlash between the internal gear 58b of the output gear 58 and the holder-side gear 73. Therefore, the amount of rotation of the drive valve 40 relative to the amount of rotation of the output gear 58 differs between the forward rotation direction and the reverse rotation direction. Therefore, the control device 60 is configured to add the amount of backlash that exists between the internal gear 58b and the holder-side gear 73 as a correction value to the amount of rotation of the output gear 58 corresponding to the valve position command value, and drive the electric motor 54.

[0082] In detail, when the control device 60 drives the electric motor 54 etc. in the forward rotation direction and then in the reverse rotation direction, the control device 60 adds the amount of backlash as a correction value to the amount of rotation of the output gear 58 corresponding to the valve position command value, and drives the electric motor 54. Furthermore, when the control device 60 drives the electric motor 54 etc. in the reverse rotation direction and then in the forward rotation direction, the control device 60 adds the amount of backlash as a correction value to the amount of rotation of the output gear 58 corresponding to the valve position command value, and drives the electric motor 54.

[0083] The control device 60 of the second embodiment learns the amount of backlash in substantially the same manner as the first embodiment. As described in the first embodiment with reference to FIG. 10, the control device 60 controls the torque generated by the actuator in accordance with the lower limit value μ of the range of the friction force. １ Specifically, the control device 60 performs backlash amount learning by setting the torque to be smaller than 0 and I １ The control device 60 supplies a motor supply current smaller than the predetermined value to the electric motor 54, thereby learning the amount of backlash. As a result, the control device 60 drives the electric motor 54 with a torque that rotates only the electric motor 54 and the torque transmission mechanism 53, without rotating the actuated valve 40, and can learn the amount of backlash.

[0084] 11 , the control device 60 starts learning the amount of backlash at time t1 and continues energizing the electric motor 54 to rotate it in the forward direction from time t1 to time t3. At this time, as shown by solid line Q, the actual rotation amount of the electric motor 54 gradually increases in the forward direction from time t1 to time t2. However, at time t2, the rotation of the electric motor 54 stops due to frictional force generated between the drive valve 40 and the fixed valve 30. The control device 60 detects the position at which the electric motor 54 stops based on information detected by the position detection sensor 59.

[0085] Next, the control device 60 continues to energize the electric motor 54 so that it rotates in the reverse direction from time t4 to time t7. At this time, as shown by solid line Q, the actual rotation amount of the electric motor 54 gradually increases in the reverse direction from time t5 to time t6. However, at time t6, the rotation of the electric motor 54 stops due to frictional force generated between the drive valve 40 and the fixed valve 30. The control device 60 detects the position at which the electric motor 54 stops based on information detected by the position detection sensor 59.

[0086] Next, the control device 60 calculates the difference in rotation amount between the stop position in the forward rotation direction detected at time t2 and the stop position in the reverse rotation direction detected at time t6. The control device 60 then learns this calculated difference as the amount of backlash present in the torque transmission path. The control device 60 stores this learned amount of backlash in its own non-volatile memory. The control device 60 then adds the learned amount of backlash as a correction value to the valve position command value and drives the electric motor 54.

[0087] The valve device 1 of the second embodiment described above has the following advantages. That is, in learning the amount of backlash, the control device 60 provided in the valve device 1 of the second embodiment drives the electric motor 54 with a torque that rotates only the electric motor 54 and the torque transmission mechanism 53, without causing the drive valve 40 to rotate due to friction between the fixed valve 30 and the drive valve 40. The control device 60 then learns the difference in rotation amount between the stop position in the forward rotation direction and the stop position in the reverse rotation direction of the torque transmission mechanism 53, detected by the position detection sensor 59, as the amount of backlash. As a result, the valve device 1 can achieve the same advantages as the first embodiment described above even when using a general electric motor 54 without using the step motor 52.

[0088] Third Embodiment A third embodiment will be described. The third embodiment is different from the second embodiment in the configuration of the position detection sensor, but is otherwise similar to the second embodiment. Therefore, only the differences from the second embodiment will be described.

[0089] 13 , the actuator 50 provided in the valve device 1 of the third embodiment has, within a case 51, an electric motor 54, a position detection sensor 591, a torque transmission mechanism 53, and a control device 60. The position detection sensor 591 of the third embodiment detects the rotational position of the electric motor 54. Information detected by the position detection sensor 591 is transmitted to the control device 60. The control device 60 is configured to be able to calculate the amount of rotation of the electric motor 54 based on the information transmitted from the position detection sensor 591.

[0090] The control device 60 drives the electric motor 54 in accordance with a valve position command value based on a request from the vehicle-side ECU 62, and moves the actuated valve 40 to a rotational position according to the valve position command value. For example, the control device 60 performs feedback control or feedforward control on the energization of the electric motor 54 based on information detected by the position detection sensor 591 so that the actuated valve 40 moves to a rotational position according to the valve position command value.

[0091] The control device 60 of the third embodiment is also configured to add the amount of backlash present in the torque transmission path as a correction value to the rotation amount of the electric motor 54 corresponding to the valve position command value, and drive the electric motor 54. Note that the backlash amount learning by the control device 60 of the third embodiment is substantially the same as that of the second embodiment, and therefore a description thereof will be omitted.

[0092] The valve device 1 of the third embodiment described above has the following advantages. In learning the amount of backlash, the control device 60 provided in the valve device 1 of the third embodiment drives the electric motor 54 with a torque that rotates only the electric motor 54 and the torque transmission mechanism 53, without causing the drive valve 40 to rotate due to friction between the fixed valve 30 and the drive valve 40. The control device 60 then learns the difference in rotation amount between the stop position in the forward rotation direction and the stop position in the reverse rotation direction of the electric motor 54, detected by the position detection sensor 591, as the amount of backlash. As a result, the valve device 1 of the third embodiment can also achieve the same advantages as the first and second embodiments.

[0093] (Fourth embodiment) A fourth embodiment will be described. The fourth embodiment is different from the first embodiment in that the configuration of the valve device is changed from a disk valve to a cylindrical valve, but is otherwise similar to the first embodiment, and therefore only the differences from the first embodiment will be described.

[0094] As shown in FIGS. 14 and 15, the valve device 2 of the fourth embodiment is a cylindrical valve including a first housing 80, a second housing 88, a drive valve 90, a fixed valve 97, an actuator 50, and the like.

[0095] The first housing 80 has a cylindrical portion 81 and a top plate 82 that closes one axial side of the cylindrical portion 81. A valve chamber 100 through which a fluid flows is formed inside the cylindrical portion 81. Furthermore, one radial side of the first housing 80 is provided with a plurality of ports 83 that serve as fluid passages that communicate with the valve chamber 100.

[0096] The second housing 88 is a cover member that closes the opening on the other side of the axial direction of the cylindrical portion 81 of the first housing 80 .

[0097] The actuated valve 90 is inserted into the first housing 80 and is rotatable about a predetermined axis CL. The outer shape of the actuated valve 90 is formed to conform to a generally cylindrical shape. The actuated valve 90 has multiple flow paths 92 formed to be recessed radially inward from a radially outer outer wall 91. By changing the rotational position of the actuated valve 90, the multiple flow paths 92 of the actuated valve 90 are connected to the multiple ports 83 of the first housing 80, thereby switching between communication and blocking between the multiple ports 83. In addition, by changing the rotational position of the actuated valve 90, the flow path area through which the multiple ports 83 communicate with each other can be adjusted. The configuration of the multiple flow paths 92 of the actuated valve 90 can be set as desired.

[0098] An input shaft 93 is provided on one axial side of the drive valve 90. An input gear 94 is provided on the input shaft 93. The input gear 94 passes through a hole 84 provided in the top plate 82 of the first housing 80 and meshes with an output gear (not shown) of the actuator 50. In addition, a shaft portion 95 is provided on the other axial side of the drive valve 90. The shaft portion 95 is rotatably supported in a bearing hole 89 provided in the second housing 88.

[0099] A fixed valve 97 is provided between a portion of the inner wall of the tubular portion 81 of the first housing 80 where the multiple ports 83 are formed and an outer wall 91 on the radially outer side of the drive valve 90. Circumferential movement of the fixed valve 97 is restricted by a step portion 85 provided on the inner wall of the first housing 80. The fixed valve 97 also has multiple flow ports 98 as holes at positions corresponding to the multiple ports 83 provided in the first housing 80. The fixed valve 97 is formed of resin, rubber, or the like, and is press-fitted between the portion of the inner wall of the tubular portion 81 of the first housing 80 where the multiple ports 83 are formed and the drive valve 90. Therefore, the fixed valve 97 can generate frictional force between the fixed valve 97 and the drive valve 90 due to its own elasticity.

[0100] The actuator 50 is provided on the top plate 82 side of the first housing 80. The actuator 50 has a step motor or electric motor, a torque transmission mechanism, a control device, and the like (not shown) inside a case 51. The configurations and operations of the actuator 50 and the control device are substantially the same as those described in the first to third embodiments, and therefore description thereof will be omitted.

[0101] The valve device 2 of the fourth embodiment described above provides the following advantageous effects. The fixed valve 97 provided in the valve device 2 of the fourth embodiment is made of resin or rubber, and is press-fitted between the first housing 80 and the actuated valve 90. The fixed valve 97 is capable of generating a frictional force between the fixed valve 97 and the actuated valve 90 by its own elasticity. As a result, the valve device 2 of the fourth embodiment can generate a frictional force between the fixed valve 97 and the actuated valve 90 without using a component such as the compression spring 75. The valve device 2 of the fourth embodiment can also provide advantageous effects similar to those of the first to third embodiments.

[0102] (Other embodiments)

[0103] (1) In the first to third embodiments, the torque transmission mechanism 53 transmits the torque output by the step motor 52 to the holder 71, which is a member connected to the actuated valve 40. However, the present invention is not limited to this. For example, the holder 71 and the shaft 70 may be eliminated, and the torque output by the step motor 52 may be transmitted directly from the torque transmission mechanism 53 to the actuated valve 40.

[0104] (2) In the first embodiment, the valve device 1 has been described as having two fluid inlets 12, 13 and three fluid outlets 14, 15, 16. However, the present invention is not limited to this, and the number of fluid inlets 12, 13 and fluid outlets 14, 15, 16 can be changed as desired. The number of outer passages 120 and inner passages 110 provided in the housing can also be changed as desired. The number of inner holes 36 and outer holes 34 in the fixed valve 30 can also be changed as desired, and the number of through holes 43 and grooves 42 in the actuated valve 40 can also be changed as desired. The valve device 1 can also be used so that fluid flows in through the fluid outlets 14, 15, 16 and flows out through the fluid inlets 12, 13.

[0105] (3) In the first embodiment, the drive valve 40 is described as having both the through hole 43 and the groove portion 42, but this is not limited thereto, and the drive valve 40 may be configured to have either the through hole 43 or the groove portion 42.

[0106] (4) In the above embodiments, a disk valve and a cylindrical valve are used as examples of the valve device. However, the valve device and its control can be applied to a wide range of valves, such as ball valves.

[0107] The present disclosure is not limited to the above-described embodiments and can be modified as appropriate. Furthermore, the above-described embodiments and portions thereof are not unrelated to each other and can be combined as appropriate unless the combination is clearly impossible. It goes without saying that, in each of the above embodiments, the elements constituting the embodiments are not necessarily essential unless specifically stated as essential or clearly considered essential in principle. Furthermore, in each of the above embodiments, when numerical values ​​such as the number, values, amounts, and ranges of components of the embodiments are mentioned, they are not limited to the specific numbers unless specifically stated as essential or clearly limited to a specific number in principle. Furthermore, in each of the above embodiments, when the shape, positional relationship, etc. of components, etc. are mentioned, they are not limited to the shape, positional relationship, etc., unless specifically stated or limited to a specific shape, positional relationship, etc. in principle.

[0108] The control device and methods described herein may be implemented by a special-purpose computer configured with a processor and memory programmed to perform one or more functions embodied in a computer program. Alternatively, the control device and methods described herein may be implemented by a special-purpose computer configured with a processor configured with one or more dedicated hardware logic circuits. Alternatively, the control device and methods described herein may be implemented by one or more special-purpose computers configured with a processor and memory programmed to perform one or more functions in combination with a processor configured with one or more hardware logic circuits. Furthermore, the computer program may be stored as instructions executed by a computer on a computer-readable non-transitory tangible storage medium.

[0109] (Aspects of the Present Disclosure) The above-described present disclosure can be understood from the following aspects, for example. [First Aspect] A valve device for controlling the flow of a fluid, comprising: a housing (10, 20, 80, 88) having a valve chamber (100) through which a fluid flows and a fluid passage (110, 120, 83) communicating with the valve chamber; a fixed valve (30, 97) fixed to the inside of the housing and having a hole (34, 36, 98) communicating with the valve chamber and the fluid passage; a drive valve (40, 90) provided rotatably about a predetermined axis (CL) while in sliding contact with the fixed valve, and adjusting a flow passage area through which the valve chamber and the fluid passage communicate with each other, or a flow passage area through which a plurality of the fluid passages communicate with each other; an actuator (50) having a step motor (52) and a torque transmission mechanism (53) that transmits torque output by the step motor to a member (71) connected to the drive valve or to the drive valve, and rotating the drive valve; A valve device comprising: a control device (60) capable of detecting an out-of-step position where the step motor loses step because the rotation amount of the step motor does not reach a motor rotation amount command value commanded to the step motor, driving the step motor with a torque that rotates only the step motor and the torque transmission mechanism without causing the drive valve to rotate due to friction between the fixed valve and the drive valve, and learning a difference in the rotation amount between the out-of-step position in the forward rotation direction of the step motor and the out-of-step position in the reverse rotation direction of the step motor as a backlash. [Second Aspect] The valve device according to the first aspect, wherein the control device adds the backlash as a correction value to the rotation amount of the step motor corresponding to a valve opening command value that is a rotational position of the drive valve based on a request from an electronic control device (62) on a vehicle, and drives the step motor to rotate. [Third Aspect] The valve device according to the first or second aspect, wherein the control device stores in its own memory a predetermined threshold value that defines a design normal range for the backlash amount, and is configured to determine an abnormal state when the backlash amount exceeds the predetermined threshold value.[Fourth Aspect] The valve apparatus according to any one of the first to third aspects, wherein the control device is configured to adjust the torque output by the step motor when learning the amount of backlash by supplying to the step motor a current value that is smaller than the current value that is supplied to the step motor when rotating the drive valve. [Fifth Aspect] The valve apparatus according to any one of the first to fourth aspects, wherein the control device executes control to gradually decrease the current value supplied to the step motor from the current value that is supplied to the step motor when rotating the drive valve, and sets a current value that is smaller than the current value when rotation of the step motor stops as the current value that is supplied to the step motor when learning the amount of backlash. [Sixth Aspect] The valve apparatus according to any one of the first to fifth aspects, wherein the valve apparatus constitutes part of a fluid circulation system that circulates fluid through vehicle components mounted on a vehicle, and the control device learns the amount of backlash after power to the fluid circulation system is turned off. [Seventh Aspect] The valve device according to any one of the first to sixth aspects, wherein the control device records the learned amount of backlash in its own non-volatile memory. [Eighth Aspect] The valve device according to any one of the first to fifth and seventh aspects, wherein the valve device constitutes part of a fluid circulation system that circulates a fluid through vehicle components mounted on a vehicle, and the control device learns the amount of backlash immediately after the fluid circulation system is powered on. [Ninth Aspect] The valve device according to any one of the first to eighth aspects, wherein the valve device constitutes part of a fluid circulation system that circulates a fluid through vehicle components mounted on a vehicle, and the control device is capable of acquiring an outside air temperature outside the vehicle cabin, a temperature of a fluid flowing through the valve device in the fluid circulation system, or a temperature inside the actuator, and drives the step motor to rotate by adding a value obtained by correcting the amount of backlash based on the acquired temperature information to an amount of rotation of the step motor corresponding to a valve position command value that is a rotational position of the drive valve based on a request from an electronic control device on the vehicle side.[Tenth Aspect] The valve device according to any one of the first to ninth aspects, further comprising a compression spring (75) that presses the drive valve against the fixed valve (30) and generates a frictional force between the drive valve and the fixed valve or an inner wall of the housing. [Eleventh Aspect] The valve device according to any one of the first to ninth aspects, wherein the fixed valve (97) is formed of resin or rubber and is press-fitted between the drive valve and the housing, and is capable of generating a frictional force between the fixed valve and the drive valve. [Twelfth Aspect] A valve device for controlling a flow of a fluid, comprising: a housing (10, 20, 80, 88) having a valve chamber (100) through which a fluid flows and a fluid passage (110, 120, 83) communicating with the valve chamber; a fixed valve (30, 97) fixed to the inside of the housing and having a hole (34, 36, 98) communicating with the valve chamber and the fluid passage; a drive valve (40, 90) provided rotatably about a predetermined axis (CL) while in sliding contact with the fixed valve, and adjusting a flow passage area through which the valve chamber and the fluid passage communicate with each other, or a flow passage area through which a plurality of the fluid passages communicate with each other; an actuator (50) having an electric motor (54) and a torque transmission mechanism (53) that transmits torque output by the electric motor to a member (71) connected to the drive valve or to the drive valve, and rotating the drive valve; and a position detection sensor (59, 591) that detects a rotational position of the electric motor or the torque transmission mechanism. a control device (60) that drives the electric motor with a torque that rotates only the electric motor and the torque transmission mechanism without causing the drive valve to rotate due to friction between the fixed valve and the drive valve, and that learns the difference in rotation amount between the stop position in the forward rotation direction and the stop position in the reverse rotation direction of the electric motor or the torque transmission mechanism detected by the position detection sensor as the amount of backlash.[Thirteenth Aspect] A control device for controlling the actuation of a valve device, comprising: a housing (10, 20, 80, 88) having a valve chamber (100) through which a fluid flows and a fluid passage (110, 120, 83) communicating with the valve chamber; a fixed valve (30, 97) fixed to the inside of the housing and having a hole (34, 36, 98) communicating with the valve chamber and the fluid passage; a drive valve (40, 90) provided rotatably about a predetermined axis (CL) while in sliding contact with the fixed valve, and adjusting a flow passage area through which the valve chamber and the fluid passage communicate with each other, or a flow passage area through which a plurality of the fluid passages communicate with each other; and an actuator (50) having a step motor (52) and a torque transmission mechanism (53) that transmits torque output by the step motor to a member (71) connected to the drive valve or to the drive valve, and rotating the drive valve, A control device that can detect an out-of-step position where the step motor loses step because the rotation amount of the step motor does not reach a motor rotation amount command value commanded to the step motor, drives the step motor with a torque that rotates only the step motor and the torque transmission mechanism without causing the drive valve to rotate due to frictional force between the fixed valve and the drive valve, and learns the difference in rotation amount between the out-of-step position in the forward rotation direction of the step motor and the out-of-step position in the reverse rotation direction as the amount of backlash.[Fourteenth Aspect] A control device for controlling the operation of a valve device, comprising: a housing (10, 20, 80, 88) having a valve chamber (100) through which a fluid flows and a fluid passage (110, 120, 83) communicating with the valve chamber; a fixed valve (30, 97) fixed to the inside of the housing and having a hole (34, 36, 98) communicating with the valve chamber and the fluid passage; a drive valve (40, 90) provided rotatably about a predetermined axis (CL) while in sliding contact with the fixed valve, and adjusting a flow passage area through which the valve chamber and the fluid passage communicate with each other, or a flow passage area through which a plurality of the fluid passages communicate with each other; an actuator (50) having an electric motor (54) and a torque transmission mechanism (53) that transmits torque output by the electric motor to a member (71) connected to the drive valve or to the drive valve, and rotating the drive valve; and a position detection sensor (59, 591) that detects a rotational position of the electric motor or the torque transmission mechanism, A control device that drives the electric motor with a torque that rotates only the electric motor and the torque transmission mechanism, without the drive valve rotating due to friction between the fixed valve and the drive valve, and learns the difference in rotation amount between the stop position in the forward rotation direction and the stop position in the reverse rotation direction of the electric motor or the torque transmission mechanism detected by the position detection sensor as the amount of backlash.

[0110] The twelfth to fourteenth aspects can be combined as appropriate with the contents of the second to eleventh aspects.

Claims

1. A valve device for controlling the flow of a fluid, comprising: a housing (10, 20, 80, 88) having a valve chamber (100) through which a fluid flows and a fluid passage (110, 120, 83) communicating with the valve chamber; a fixed valve (30, 97) fixed to the inside of the housing and having a hole (34, 36, 98) communicating with the valve chamber and the fluid passage; a drive valve (40, 90) rotatable about a predetermined axis (CL) while in sliding contact with the fixed valve, for adjusting the flow passage area where the valve chamber and the fluid passage communicate with each other, or the flow passage area where a plurality of the fluid passages communicate with each other; an actuator (50) having a step motor (52) and a torque transmission mechanism (53) for transmitting the torque output by the step motor to a member (71) connected to the drive valve or to the drive valve, and for rotating the drive valve; a control device (60) that is capable of detecting an out-of-step position where the step motor loses step because the rotation amount of the step motor does not reach a motor rotation amount command value commanded to the step motor, drives the step motor with a torque that rotates only the step motor and the torque transmission mechanism without causing the drive valve to rotate due to frictional force between the fixed valve and the drive valve, and learns the difference in rotation amount between the out-of-step position in the forward rotation direction of the step motor and the out-of-step position in the reverse rotation direction as the amount of backlash.

2. The valve device according to claim 1, wherein the control device adds the amount of backlash as a correction value to the amount of rotation of the step motor corresponding to a valve opening command value, which is the rotational position of the actuated valve based on a request from an electronic control device (62) on the vehicle side, and drives the step motor to rotate.

3. A valve device as described in claim 1 or 2, wherein the control device stores in its own memory a predetermined threshold value that defines a design normal range for the amount of backlash, and is configured to determine that an abnormal state exists if the amount of backlash exceeds the predetermined threshold value.

4. The valve device according to claim 1 or 2, wherein the control device is configured to adjust the torque output by the step motor when learning the amount of backlash by supplying a current value to the step motor that is smaller than the current value supplied to the step motor when rotating the drive valve.

5. A valve device as claimed in claim 1 or 2, wherein the control device executes control to gradually reduce the current value supplied to the step motor from the current value supplied to the step motor when rotating the drive valve, and sets a current value smaller than the current value when the rotation of the step motor stops as the current value supplied to the step motor when learning the amount of backlash.

6. The valve device according to claim 1 or 2, which constitutes part of a fluid circulation system that circulates fluid to vehicle components mounted on a vehicle, and the control device learns the amount of backlash after the power to the fluid circulation system is turned off.

7. The valve device according to claim 1 or 2, wherein the control device records the learned amount of backlash in its own non-volatile memory.

8. The valve device according to claim 1 or 2, which constitutes part of a fluid circulation system that circulates fluid to vehicle components mounted on a vehicle, and the control device learns the amount of backlash immediately after the fluid circulation system is powered on.

9. The valve device constitutes part of a fluid circulation system that circulates fluid to vehicle parts mounted on a vehicle, and the control device is capable of acquiring the outside air temperature outside the passenger compartment, or the temperature of the fluid flowing through the valve device in the fluid circulation system, or the temperature inside the actuator, and drives the step motor to rotate by adding a value obtained by correcting the amount of backlash based on the acquired temperature information as a correction value to the amount of rotation of the step motor corresponding to a valve opening command value, which is the rotational position of the drive valve based on a request from an electronic control device on the vehicle side.

10. The valve device according to claim 1 or 2, further comprising a compression spring (75) that presses the actuating valve against the fixed valve (30) and generates a friction force between the actuating valve and the fixed valve or an inner wall of the housing.

11. The valve device according to claim 1 or 2, wherein the fixed valve (97) is formed from resin or rubber and is press-fit between the drive valve and the housing, thereby generating a frictional force between the fixed valve and the drive valve.

12. A valve device for controlling the flow of a fluid, comprising: a housing (10, 20, 80, 88) having a valve chamber (100) through which a fluid flows and a fluid passage (110, 120, 83) communicating with the valve chamber; a fixed valve (30, 97) fixed to the inside of the housing and having a hole (34, 36, 98) communicating with the valve chamber and the fluid passage; a drive valve (40, 90) rotatable about a predetermined axis (CL) while in sliding contact with the fixed valve, and adjusting the flow passage area where the valve chamber communicates with the fluid passage or the flow passage area where a plurality of the fluid passages communicate with each other; an actuator (50) having an electric motor (54) and a torque transmission mechanism (53) that transmits the torque output by the electric motor to a member (71) connected to the drive valve or to the drive valve, and rotating the drive valve; and a position detection sensor (59, 591) that detects the rotational position of the electric motor or the torque transmission mechanism. a control device (60) that drives the electric motor with a torque that rotates only the electric motor and the torque transmission mechanism without causing the drive valve to rotate due to friction between the fixed valve and the drive valve, and that learns the difference in rotation amount between the stop position in the forward rotation direction and the stop position in the reverse rotation direction of the electric motor or the torque transmission mechanism detected by the position detection sensor as the amount of backlash.

13. A control device for controlling the operation of a valve device comprising: a housing (10, 20, 80, 88) having a valve chamber (100) through which a fluid flows and a fluid passage (110, 120, 83) communicating with the valve chamber; a fixed valve (30, 97) fixed to the inside of the housing and having a hole (34, 36, 98) communicating with the valve chamber and the fluid passage; a drive valve (40, 90) rotatable about a predetermined axis (CL) while in sliding contact with the fixed valve, and adjusting the flow passage area where the valve chamber and the fluid passage communicate with each other, or the flow passage area where a plurality of the fluid passages communicate with each other; and an actuator (50) having a step motor (52) and a torque transmission mechanism (53) that transmits the torque output by the step motor to a member (71) connected to the drive valve or to the drive valve, and rotating the drive valve, A control device that can detect an out-of-step position where the step motor loses step because the rotation amount of the step motor does not reach a motor rotation amount command value commanded to the step motor, drives the step motor with a torque that rotates only the step motor and the torque transmission mechanism without causing the drive valve to rotate due to frictional force between the fixed valve and the drive valve, and learns the difference in rotation amount between the out-of-step position in the forward rotation direction of the step motor and the out-of-step position in the reverse rotation direction as the amount of backlash.

14. A control device for controlling the operation of a valve device, comprising: a housing (10, 20, 80, 88) having a valve chamber (100) through which a fluid flows and a fluid passage (110, 120, 83) communicating with the valve chamber; a fixed valve (30, 97) fixed to the inside of the housing and having a hole (34, 36, 98) communicating with the valve chamber and the fluid passage; a drive valve (40, 90) rotatable about a predetermined axis (CL) while in sliding contact with the fixed valve, for adjusting the flow passage area connecting the valve chamber and the fluid passage or the flow passage area connecting a plurality of the fluid passages; an actuator (50) having an electric motor (54) and a torque transmission mechanism (53) for transmitting torque output by the electric motor to a member (71) connected to the drive valve or to the drive valve, for rotating the drive valve; and a position detection sensor (59, 591) for detecting the rotational position of the electric motor or the torque transmission mechanism, A control device that drives the electric motor with a torque that rotates only the electric motor and the torque transmission mechanism, without the drive valve rotating due to friction between the fixed valve and the drive valve, and learns the difference in rotation amount between the stop position in the forward rotation direction and the stop position in the reverse rotation direction of the electric motor or the torque transmission mechanism detected by the position detection sensor as the amount of backlash.

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