Electric valve and electric valve unit

Abstract

The present invention provides an electric valve and an electric valve unit capable of securing versatility and enhancing scalability of control.　In this electric valve in which a detection signal can be input from a sensor for detecting at least one of pressure and temperature of a fluid entering the electric valve or discharged from the electric valve, the sensor has: flexible wiring capable of transmitting a detection signal; a second terminal connected to the wiring; and a second connector connectable to a first connector of the electric valve. When the first connector and the second connector are connected to each other, a first terminal of the electric valve and the second terminal are engaged with each other so as to be able to transmit a signal. A control unit of the electric valve acquires a detection signal from the sensor via the first terminal and the second terminal, and generates a drive signal for driving a motor of the electric valve on the basis of the detection signal.

Description

Motorized valves and motorized valve units

[0001] The present invention relates to a motor-operated valve and a motor-operated valve unit.

[0002] 2. Description of the Related Art Conventionally, so-called motor-operated valves that use an electric motor to open and close a valve include those that transmit the rotation of a rotor to a screw mechanism to open and close the valve.

[0003] Patent document 1 discloses an electric valve having a stator unit arranged parallel to the vertical direction on a main board, a sub-board arranged perpendicular to the main board, and a magnetic sensor provided on the sub-board.

[0004] When controlling the valve opening in such a conventional motor-operated valve, a magnetic sensor detects the current valve opening (including a signal corresponding to the current valve opening) and outputs it to a higher-level system ECU via a sub-board and a main board. In parallel with this, a pressure / temperature sensor located in the flow path through which the fluid controlled by the motor-operated valve passes detects the pressure / temperature of the fluid and generates corresponding pressure / temperature signals to output to the system ECU. The system ECU, which receives the current valve opening and the pressure / temperature signals, calculates the required valve opening based on these and generates a control signal. The control signal is then output to the stator via the main board of the motor-operated valve, thereby rotating the rotor by the desired angle.

[0005] International Publication No. 2022 / 168651

[0006] Because pressure / temperature sensors generate the pressure / temperature signals necessary to control the valve opening of motor-operated valves, integrating the pressure / temperature sensor with the motor-operated valve is being considered. However, incorporating the pressure / temperature sensor and the motor-operated valve in the same housing, for example, requires a dedicated housing design for each component to which the pressure / temperature sensor and the motor-operated valve are attached, resulting in a loss of versatility. There is also a need for expandability in the control of motor-operated valves.

[0007] An object of the present invention is to provide a motor-operated valve and a motor-operated valve unit that ensure versatility and can enhance the expandability of control.

[0008] In order to achieve the above object, the motor-operated valve according to the present invention is an electric valve that can input a detection signal from a sensor that detects at least one of the pressure and temperature of a fluid flowing into or out of the motor-operated valve, and comprises: a valve body having a valve port and a valve seat surrounding the valve port; a cylindrical can attached to the valve body; a rotor arranged inside the can; a stator arranged outside the can; a cover that covers the stator and has a first connector; a valve body that is movable in an axial direction toward and away from the valve seat; a feed screw mechanism that converts the rotational movement of the rotor into axial movement of the valve body; and a substrate that is arranged within the cover and has a control unit connected to a first terminal, wherein the sensor has flexible wiring that can transmit a detection signal, a second terminal connected to the wiring, and a second connector that can be connected to the first connector, and when the first connector and the second connector are connected, the first terminal and the second terminal engage to be able to transmit a signal, and the control unit acquires the detection signal from the sensor via the first terminal and the second terminal, and generates a drive signal to drive the motor based on the detection signal.

[0009] In order to achieve the above object, the motor-operated valve unit of the present invention includes: a sensor that detects at least one of the pressure and temperature of a fluid flowing into or out of the motor-operated valve; and a motor-operated valve to which a detection signal can be input from the sensor, wherein the sensor has: a flexible wiring that can transmit a detection signal; a second terminal connected to the wiring; and a second connector, and the motor-operated valve includes: a valve body having a valve port and a valve seat surrounding the valve port; a cylindrical can attached to the valve body; a rotor disposed inside the can; a stator disposed outside the can; a cover that covers the stator and has a first connector connectable to the second connector; a valve element that is movable in the axial direction toward and away from the valve seat; a feed screw mechanism that converts rotational movement of the rotor into axial movement of the valve element; and a substrate that is disposed within the cover and has a control unit and a first terminal connected to the control unit, and when the first connector is connected to the second connector, the first terminal and the second terminal engage to be able to transmit a signal, The control unit acquires a detection signal from the sensor via the first terminal and the second terminal, and generates a drive signal for driving the motor based on the detection signal.

[0010] According to the present invention, it is possible to provide a motor-operated valve and a motor-operated valve unit that ensure versatility and can enhance the expandability of control.

[0011] Fig. 1 is a schematic diagram showing a control circuit including a motor-operated valve according to this embodiment. Fig. 2 is a longitudinal sectional view showing the motor-operated valve according to this embodiment. Fig. 3 is a sectional view showing the motor-operated valve according to this embodiment attached to a flow path block. Fig. 4 is a longitudinal sectional view of a motor-operated valve according to a first modified example. Fig. 5 is a longitudinal sectional view of a motor-operated valve according to a second modified example.

[0012] Hereinafter, a motor-operated valve according to an embodiment of the present invention will be described with reference to the drawings. In this specification, a pressure / temperature sensor refers to a sensor that detects at least one of pressure and temperature and generates a corresponding detection signal. However, sensors other than a pressure / temperature sensor (such as a position sensor or an encoder) may be combined with the motor-operated valve. In addition, the combination of the motor-operated valve and the sensor is referred to as a motor-operated valve unit.

[0013] [Control Circuit] Fig. 1 is a schematic diagram showing a control circuit including an electric valve according to this embodiment. Here, an example in which an electric valve is applied to a refrigeration cycle (air conditioner) using a refrigerant as a fluid will be described. In Fig. 1, an electric valve 1, a solenoid valve 200, and a pressure / temperature sensor 300 are installed along a flow path PS through which the refrigerant flows as a fluid. The entire refrigeration cycle is controlled by a system ECU (simply referred to as ECU) 400. The electric valve 1 has the function of restricting the cross-sectional area of ​​the flow path PS through which the refrigerant passes.

[0014] The motor-operated valve 1 has a stator 50 including a main board 100. The main board 100 is mounted with a microcomputer 101 equipped with a CPU, ROM, RAM, timer, A / D, I / O, etc., a memory 102 capable of storing numerical values, a solenoid driver 103, a motor driver 104, and a regulator 105 for supplying power to each part of the main board.

[0015] The solenoid valve 200 has a switching valve element 201 that opens or closes the flow path PS, and a coil 202 that drives the switching valve element 201. However, the solenoid valve 200 does not necessarily have to be provided.

[0016] The pressure / temperature sensor 300 has a detection element 301 that detects at least one of the pressure and temperature of the refrigerant passing through the flow path PS and generates a detection signal corresponding thereto.

[0017] The microcomputer 101, which is the control unit, is capable of inputting and outputting numerical values ​​to and from the memory 102, and is able to input a detection signal from the detection element 301, calculate the valve opening degree of the motor-operated valve 1 based on the detection signal, and accordingly drive and control the stepping motor (also referred to as a motor) 5 via a motor driver 104 to displace the valve element 4 of the motor-operated valve 1. The microcomputer 101 also outputs the input detection signal from the detection element 301 to the ECU 400 via a bus BS, and can also receive a control signal from the ECU 400. The microcomputer 101 can also open or close the flow path PS by displacing the switching valve element 201 via a solenoid driver 103.

[0018] A sensor 107 disposed on the sub-board 106 can magnetically detect the angle of the rotor of the stepping motor 5. The microcomputer 101 receives a detection signal from the sensor 107 and can output the signal to the ECU 400.

[0019] 2 is a longitudinal cross-sectional view showing the motor-operated valve 1 according to this embodiment, together with the pressure / temperature sensor 300. In this specification, the direction from the rotor to the valve seat is defined as downward, and the direction from the valve seat to the rotor is defined as upward.

[0020] The motor-operated valve 1 mainly comprises a valve body 2, a can 3, a valve element 4 arranged in the internal space of the valve body 2, a stepping motor 5 that generates a rotational torque to drive the valve element 4, a speed reduction mechanism 6 arranged inside the can 3 that reduces the rotational torque of the stepping motor 5 and transmits the driving force to the valve element 4 via an output shaft 7, and a feed screw mechanism 9. The speed reduction mechanism 6 may be omitted.

[0021] A pair of bobbins 52 and a stator coil 53 are arranged on the outer periphery of the cylindrical portion of the can 3, and a yoke 51 surrounding them is arranged on the outer periphery of the can 3. The stator 50 is formed by covering the outer periphery with a resin molded cover 56. The stepping motor 5 is made up of the stator 50 and a rotor 57, which will be described later.

[0022] A portion of the outer periphery of the resin molded cover 56 protrudes radially outward, forming a hollow housing portion 56a, whose open portion is shielded by the lid member 58. The lid member 58 is joined to the housing portion 56a to form part of the resin molded cover 56. The lid member 58 has a plate portion 58a that covers the opening of the housing portion 56a and a hollow cylindrical portion 58b that protrudes outward from the plate portion 58a perpendicular to the axis L. The internal space of the hollow cylindrical portion 58b penetrates the plate portion 58a. The hollow cylindrical portion 58b forms the first connector. Note that by preparing lid members 58 with hollow cylindrical portions 58b of different shapes and selecting one to match the second connector described below, the resin molded cover 56 can be used in common with the lid member 58. Multiple hollow cylindrical portions 58b may be provided on one plate portion 58a.

[0023] A main board 100 is disposed inside the housing 56a and parallel to the axis L. The rear side of the main board 100 is supported by a support 56f extending from the outer periphery of the stator coil 53. A female terminal (first terminal) 108 connected to the microcomputer 101 is disposed on the main board 100 so as to face the hollow cylindrical portion 58b. When multiple hollow cylindrical portions 58b are provided, multiple female terminals 108 can be formed accordingly.

[0024] A male terminal (second terminal) 303 is attached to the tip of a flexible wiring 302 extending from the pressure / temperature sensor 300, and a resin connector portion (second connector) 304 is fixed around the wiring 302 in the vicinity of the male terminal 303. In other words, the wiring 302 passes through the center of the connector portion 304, and the male terminal 303 is connected to its end.

[0025] By inserting the male terminal 303 and the connector portion 304 into the hollow cylindrical portion 58b, the male terminal 303 can be engaged with the female terminal 108 so as to be capable of transmitting signals, thereby enabling a detection signal to be acquired from the pressure / temperature sensor 300 and input to the microcomputer 101 via the wiring 302. At this time, the outer periphery of the connector portion 304 is in close contact with the inner periphery of the hollow cylindrical portion 58b, thereby preventing external foreign matter from entering the housing portion 56a. With the connector portion 304 inserted into the hollow cylindrical portion 58b, the two may be fixed together with an adhesive.

[0026] A hollow connector portion 56b is formed on the upper portion of the housing portion 56a. A terminal 56c is arranged inside the connector portion 56b and is connected to a bus BS connected to the ECU 400 (FIG. 1). The terminal 56c is connected to the main board 100 so as to be able to transmit signals.

[0027] Inside the housing 56a, a sub-board 106 with a sensor 107 attached thereto is disposed so as to extend from the main board 100 toward the can 3. The sub-board 106 is connected to the main board 100 so as to be able to transmit signals. The sensor 107 has the function of magnetically detecting the angle of the rotor 57 which is located close to the sensor 107 across the can 3. The angle signal of the rotor 57 detected by the sensor 107 is input to the microcomputer 101 on the main board 100 via the sub-board 106.

[0028] The microcomputer 101 on the main board 100 is connected to the stator coil 53 via the motor driver 104 (FIG. 1) and the wiring 56d.

[0029] The can 3 is made of a non-magnetic metal such as stainless steel and has a cylindrical shape with a spherical top. The open lower end of the can 3 is welded and fixed to the upper end of the valve body unit 20, as described below. The thickness of the lower end of the can 3 is made thicker than the thickness of the rest of the can 3. Specifically, the rest of the can 3 is made thinner by ironing or other processes.

[0030] A valve chamber VC is defined within the valve body 2. The valve body 2 has a vertical opening 21 that passes through the valve chamber VC along the axis L, and a horizontal opening 22 that extends laterally toward the valve chamber VC in a direction perpendicular to the axis L. A hollow cylindrical valve seat member 30 is press-fitted into the inner periphery of the vertical opening 21 near the lower end of the vertical opening 21. The inner periphery of the valve seat member 30 forms an orifice passage (valve port), and its upper end constitutes a valve seat 31 that surrounds the valve port.

[0031] A cylindrical spring bearing member 26 is press-fit into the center of the vertical opening 21 of the valve body 2. The spring bearing member 26 has a central opening 26b penetrating in the direction of the axis L, a flange portion 26c abutting against the step portion 21a of the vertical opening 21, and a spring bearing seat 26d formed around the upper end of the central opening 26b.

[0032] A hollow cylindrical base material 27 is fitted into the upper part of the vertical opening 21 of the valve body 2, with its lower end abutting against the upper end of the spring bearing member 26. A male thread 27a formed on the outer periphery of the lower end of the base material 27 is threadedly engaged with an internal thread 21b formed on the inner periphery of the vertical opening 21, thereby fastening the base material 27 to the valve body 2. The base material 27 has a large-diameter cylindrical portion 27b on the lower side and a reduced-diameter cylindrical portion 27c on the upper side. The inner periphery of an annular plate 28 is fitted by press fitting into the outer periphery step at the upper end of the large-diameter cylindrical portion 27b. The outer periphery of the annular plate 28 is fixed to the lower end of the can 3 by welding or brazing.

[0033] A cylindrical rotor 57 is disposed radially inside the stator 50, sandwiching the can 3 therebetween, and its upper end is shielded by a rotor support member 59. The lower end of the resin molded cover 56 is attached to the valve body 2 at the rear by a detent (not shown) so as not to be rotatable about the axis.

[0034] The reduction mechanism 6 has, on the inner peripheral side of the rotor 57, a sun gear 61 formed integrally with the rotor support member 59, a fixed ring gear 62 fixed via a thin-walled cylindrical body 66 fixed to the outer periphery of the upper end of the base material 27, planetary gears 63 arranged between the sun gear 61 and the fixed ring gear 62 and meshing with them, a carrier 64 that supports the planetary gear 63 so that it can rotate freely, and a bottomed cylindrical output gear member 65 that has teeth on its inner peripheral that mesh with the planetary gear 63.

[0035] The number of teeth of the fixed ring gear 62 is set to be different from the number of teeth of the output gear member 65, so that the reduction mechanism 6 constitutes a paradox planetary gear reduction mechanism.

[0036] The upper end of the output shaft 7 is fitted and fixed in a central opening formed in the center of the carrier 64, and the two are rotatable integrally.

[0037] The lower end of the shaft member 8 is fitted into a hole formed in the center of the upper end of the output shaft 7. As shown in FIG. 2, the upper end of the shaft member 8 is inserted into the center hole of a support member 81. The support member 81 has an outer diameter substantially the same as the inner diameter of the can 3, and is disposed above the rotor support member 59 so as to be inscribed in the can 3. The shaft member 8 passes through the rotor support member 59 and the carrier 64, and holds them so that they can rotate relative to one another. The rotor 57 itself is held by the support member 81 and other members so as not to move up and down inside the can 3, and its positional relationship with the stator 50, which is fitted and fixed to the outside of the can 3, is always maintained constant.

[0038] 2, the feed screw mechanism 9 includes a cylindrical bearing 91, a screw shaft 92, and balls 93. The cylindrical bearing 91 has a lower end portion fixed to the inner periphery of the upper end side of the base material 27.

[0039] The cylindrical bearing 91 supports the lower surface of the carrier 64 at its upper end surface, and the output shaft 7 is inserted into the upper inner periphery of the cylindrical bearing 91 so as to be rotatable relative to the carrier 64. The cylindrical bearing 91 and the carrier 64 are preferably made of different materials. A male threaded portion 92a formed on the outer periphery of the screw shaft 92 is threadedly engaged with a female threaded portion 91a formed on the lower inner periphery of the cylindrical bearing 91. A convex portion 92b, which serves as a flat driver portion, on the screw shaft 92 is inserted into a slit-shaped recessed portion 7b formed on the lower end of the output shaft 7, so that the output shaft 7 and the screw shaft 92 are movable relative to each other in the axial direction but rotate integrally. A recessed portion is formed on the lower end of the screw shaft 92, and a ball 93 is fitted into the recessed portion and fixed to the screw shaft 92.

[0040] The rotation of the screw shaft 92 is converted into axial movement by the threading action between it and the cylindrical bearing 91, and is transmitted to the valve element 4 via the balls 93 and the ball receiving member 94. The ball receiving member 94 is fitted and fixed to a valve element holding member 95 which is press-fitted onto the upper end of the valve element 4 to form an integral unit. Note that a recess may be provided on the screw shaft 92, and a protrusion to be inserted into the recess may be provided on the output shaft 7.

[0041] In order to eliminate backlash between the female thread portion 91 a and the male thread portion 92 a in the feed screw mechanism 9, a coil spring 70 that urges the valve element 4 in the valve opening direction via the valve element holding member 95 is provided inside the base material 27. The upper end of the coil spring 70 abuts against the underside of the flange of the valve element holding member 95, and the other end abuts against the spring receiving seat 26 d of the spring receiving member 26.

[0042] The shaft portion 41 of the valve body 4 is fitted into the central opening 26b of the spring bearing member 26 so as to be slidable in the direction of the axis L, and the umbrella portion 42 connected to the lower end of the shaft portion 41 has a tapered surface 43 on its outer periphery. The tapered surface 43 is capable of being seated on the valve seat 31.

[0043] The valve element 4 is always biased in the valve opening direction (towards the feed screw mechanism 9) by the spring force of the coil spring 70, which is held in a compressed state. When the valve element 4 is pushed down in the valve closing direction by the driving force from the feed screw mechanism 9, the valve element 4 is pushed down against the spring force of the coil spring 70, causing the tapered surface 43 to seat on the valve seat 31 and close the orifice passage.

[0044] The screw shaft 92 can rotate at a reduced rotational speed relative to the rotation of the rotor 57, and the axial displacement of the screw shaft 92 corresponding to that rotation can be controlled to a small displacement, so the axial position of the valve element 4 relative to the valve seat 31 can be positioned with high resolution by the speed reduction mechanism 6. As a result, the flow path area between the tapered surface 43 and the valve seat 31 can be controlled with high precision, and the flow rate of the refrigerant passing through can be adjusted with high precision, that is, high-resolution valve opening control is achieved. When the feed screw mechanism 9 is operated in the valve opening direction, the spring force of the coil spring 70 causes the valve shaft 60 to move in conjunction with the upward movement of the screw shaft 92.

[0045] In the motor-operated valve shown in FIG. 2, the refrigerant is introduced into the can 3 through the inner and outer periphery communicating holes of the spring receiving member 26 and the gaps between the members.

[0046] 3 is a cross-sectional view showing the motor-operated valve 1 of this embodiment attached to a flow path block PB, with the solenoid valve omitted. In FIG. 3, the flow path block PB has an attachment opening OP having a female thread for attaching the motor-operated valve 1, a first flow path PS1 extending coaxially with the attachment opening OP, and a second flow path PS2 extending in a direction intersecting the attachment opening OP.

[0047] The motor-operated valve 1 can be attached to the flow path block PB by threading the male thread formed on the outer periphery of the upper part of the valve body 2 into the female thread of the mounting opening OP and inserting the outer periphery of the lower part of the valve body 2 into the first flow path PS1. At this time, O-rings OR1 and OR2 seal between the valve body 2 and the mounting opening OP and the first flow path PS1. With the motor-operated valve 1 attached to the flow path block PB, the vertical opening 21, i.e., the orifice passage, communicates with the first flow path PS1, and the horizontal opening 22 communicates with the second flow path PS2. Here, the refrigerant flows from the second flow path PS2 through the valve chamber VC to the first flow path PS1, but the refrigerant may also flow from the first flow path PS1 to the second flow path PS2.

[0048] Here, the first pressure / temperature sensor 300A arranged on the side of the flow path block PB is inserted into a detection hole DH1 that communicates with the first flow path PS1, which is downstream (after being narrowed) of the orifice path, and can detect the pressure / temperature of the refrigerant in the first flow path PS1.

[0049] In addition, a second pressure / temperature sensor 300B arranged on the underside of the flow path block PB is inserted into a detection hole DH2 communicating with the second flow path PS2, which is upstream of the orifice path (before it is narrowed), and can detect the pressure / temperature of the refrigerant in the second flow path PS2.

[0050] Furthermore, a third pressure / temperature sensor 300C arranged on the upper surface of the flow path block PB is inserted into a detection hole DH3 communicating with the second flow path PS2, which is upstream of the orifice path (before it is narrowed), and can detect the pressure / temperature of the refrigerant in the second flow path PS2.

[0051] According to this embodiment, because the first connector and the second connector are common, any of the first pressure / temperature sensor 300A to the third pressure / temperature sensor 300C can be connected to the motor-operated valve 1 using flexible wiring 302 so as to be capable of transmitting signals, thereby enhancing versatility. Therefore, when a pressure / temperature signal before or after passing through the orifice passage is required to control the motor-operated valve 1, one of the first pressure / temperature sensor 300A to the third pressure / temperature sensor 300C that generates the desired pressure / temperature signal can be selected, and the microcomputer 101 can perform processing based on the detection signal. Alternatively, if there are multiple first connectors, the microcomputer 101 may perform processing based on detection signals from multiple pressure / temperature sensors. This improves the scalability of control.

[0052] Furthermore, when the flow path block PB is installed in a narrow space, it is conceivable that other components nearby may get in the way and prevent the pressure / temperature sensor from being installed later. In such a case, it is possible to install the flow path block PB with the pressure / temperature sensor already attached, and then connect the wiring 302 extending from the pressure / temperature sensor to the motor-operated valve 1, thereby improving assembly ease.

[0053] (Operation of Motor-Operated Valve) The operation of the motor-operated valve 1 according to this embodiment will be described with reference to Figures 1 to 3. Here, it is assumed that the motor-operated valve 1 is connected to the third pressure / temperature sensor 300C.

[0054] In the valve open state, the microcomputer 101 of the motor-operated valve 1 receives a control signal requesting a desired valve opening from the external ECU 400 and a detection signal from the third pressure / temperature sensor 300C. By comparing these signals, the microcomputer 101 can determine whether the valve opening of the motor-operated valve 1 in response to the request from the ECU 400 is excessive or insufficient (i.e., whether the current flow rate is high or low relative to the allowable range of flow rate passing through the orifice passage). Note that instead of the control signal requesting the desired valve opening received by the microcomputer 101 of the motor-operated valve 1, a control signal requesting a desired flow rate may be used, and whether the flow rate is excessive or low may be determined.

[0055] If the microcomputer 101 determines that the valve opening of the motor-operated valve 1 is insufficient in response to a request from the ECU 400, the microcomputer 101 controls the valve opening to increase in order to ensure a flow rate that corresponds to the shortage. Specifically, the microcomputer 101 outputs a drive signal corresponding to the shortage to the motor driver 104, causing the stator 50 of the stepping motor 5 to generate a magnetic force. The rotor 57 is driven to rotate based on this magnetic force, generating a rotational force in a predetermined direction. This rotational force is transmitted to the reduction mechanism 6 via the rotor support member 59.

[0056] 2, the planetary gears 63 revolve around the axis L along the fixed ring gear 62 upon receiving rotational force transmitted from the sun gear 61 that is integral with the rotor support member 59, thereby causing the carrier 64 to rotate around the axis L while being decelerated. Furthermore, since the fixed ring gear 62 with which the planetary gears 63 mesh and the output gear member 65 have different numbers of teeth, the output gear member 65 can rotate at a high reduction ratio relative to the rotational speed of the sun gear 61.

[0057] Therefore, the rotational force of the rotor 57 is highly decelerated by the reduction mechanism 6 before being transmitted to the output shaft 7. Furthermore, the rotational movement of the output shaft 7 is converted into the upward movement of the screw shaft 92 via the feed screw mechanism 9, so that the valve element 4, biased by the spring force of the coil spring 70, follows the upward movement of the screw shaft 92, and the tapered surface 43 of the valve element 4 moves away from the valve seat 31, allowing the refrigerant to pass through. As a result, the amount of refrigerant flowing into the valve chest VC from the second passage PS2 of the flow path block PB through the side opening 22 increases, and the refrigerant that passes between the valve seat 31 and the valve element 4 flows out through the first passage PS1 to the outside.

[0058] When the flow rate of refrigerant passing through the second passage PS2 increases, the detection signal generated by the third pressure / temperature sensor 300C changes accordingly. Therefore, the microcomputer 101 calculates the increased flow rate of refrigerant based on the detection signal obtained from the third pressure / temperature sensor 300C and compares it with the previously calculated refrigerant shortage. If the microcomputer 101 determines that the increased flow rate is insufficient to compensate for the shortage, it causes the motor driver 104 to rotate the rotor 57 in the same direction, thereby further separating the valve disc 4 from the valve seat 31. On the other hand, if the microcomputer 101 determines that the increased flow rate is approximately equal to the shortage, it stops the rotation of the rotor 57.

[0059] On the other hand, if the microcomputer 101 determines that the valve opening of the motor-operated valve 1 is excessive in response to the request from the ECU 400, the microcomputer 101 performs control to reduce the valve opening in order to reduce the flow rate corresponding to the excess. Specifically, the microcomputer 101 outputs a drive signal corresponding to the excess to the motor driver 104, causing the stator 50 of the stepping motor 5 to generate a magnetic force with reverse characteristics. Based on this magnetic force, the rotor 57 is rotated in the reverse direction, generating a rotational force. This rotational force is transmitted to the speed reduction mechanism 6 via the rotor support member 59, which causes the valve element 4 to approach the valve seat 31 and restrict the passage of refrigerant. This reduces the amount of refrigerant passing between the valve seat 31 and the valve element 4.

[0060] When the flow rate of refrigerant passing through the second passage PS2 decreases, the detection signal generated by the third pressure / temperature sensor 300C changes accordingly. Therefore, the microcomputer 101 calculates the decreased flow rate of refrigerant based on the detection signal generated by the third pressure / temperature sensor 300C and compares it with the previously calculated excess amount of refrigerant. If the microcomputer 101 determines that the decreased flow rate does not reach the excess amount, it rotates the rotor 57 via the motor driver 104 to move the valve disc 4 closer to the valve seat 31. On the other hand, if the microcomputer 101 determines that the decreased flow rate is approximately equal to the excess amount, it stops the rotation of the rotor 57.

[0061] In the above embodiment, the microcomputer 101 corrects the control signal from the ECU 400 based on the detection signal generated by the third pressure / temperature sensor 300C, thereby controlling the rotation of the rotor 57. However, the microcomputer 101 may autonomously control the rotation of the rotor 57 based only on the detection signal generated by the third pressure / temperature sensor 300C, regardless of the control signal from the ECU 400. Even in this case, the microcomputer 101 can output the detection signal generated by the third pressure / temperature sensor 300C to the ECU 400.

[0062] Furthermore, the microcomputer 101 can also detect an abnormality in the motor-operated valve 1, for example, by comparing and monitoring the detection signals generated by the first pressure / temperature sensor 300A and the third pressure / temperature sensor 300C. Specifically, referring to Fig. 1, when the change in pressure / temperature before and after throttling, which is determined based on the detection signals generated by the first pressure / temperature sensor 300A and the third pressure / temperature sensor 300C, exceeds an allowable range for the valve opening of the motor-operated valve 1 corresponding to the control signal to the motor driver 104, the microcomputer 101 can determine that an abnormality has occurred in the motor-operated valve 1. When the microcomputer 101 determines that an abnormality has occurred in the motor-operated valve 1, it can drive and control the solenoid valve 200 (Fig. 1) via the solenoid driver 103, thereby closing the refrigerant flow path PS with the switching valve element 201. In addition, the microcontroller 101 may compare the detection signal generated by the first pressure / temperature sensor 300A or the third pressure / temperature sensor 300C in response to the valve opening degree of the electric valve 1 with a threshold value obtained through simulation, experiment, etc. to determine whether or not there is an abnormality.

[0063] 4 is a longitudinal cross-sectional view of the motor-operated valve 1A according to the first modification, showing the motor-operated valve 1A attached to the flow path block PBA. The motor-operated valve 1A of this modification differs from the embodiment described above only in the configuration of the resin mold cover 56A, the lid member 58A, and the main board 100A. The other configurations are the same as those of the embodiment described above, so the same reference numerals are used and redundant description will be omitted.

[0064] Furthermore, the main board 100A differs in the position of the female terminals 108A, but other configurations are the same as those of the above-described embodiment, so duplicated explanations of the common configurations will be omitted.

[0065] A portion of the outer periphery of the resin mold cover 56A protrudes radially outward, forming a hollow housing portion 56Aa, the opening of which is covered by a lid member 58A. The lid member 58A is a plate-like member that covers the opening of the housing portion 56Aa, and does not have a hollow cylindrical portion connected thereto. Instead, a hollow cylindrical portion 56Ac protrudes downward from the housing portion 56Aa in a direction parallel to the axis L and faces the flow path block PBA.

[0066] A main board 100A is disposed inside the housing 56Aa. A female terminal 108A connected to the microcomputer 101 (see FIG. 1) is disposed on the main board 100A facing the hollow cylindrical portion 56Ac.

[0067] In this modification, a male terminal 303 and a connector portion 304 are attached to the end of a wire 302 that extends upward through a hole HL formed in the flow path block PBA. The wire 302 is connected to a pressure / temperature sensor (not shown in FIG. 4).

[0068] Of course, the motor-operated valve 1A may be attached to a flow path block that does not have a hole HL. In this case, the wire 302 passes through the gap between the lower end of the hollow cylindrical portion 56Ac and the upper surface of the flow path block (the upper surface of the portion of the flow path block PBA where the hole HL is formed). Therefore, even if the wire 302 is pulled, the male terminal 303 and the connector portion 304 are unlikely to come off. Note that the wire 302 may be sandwiched and fixed between the lower end of the hollow cylindrical portion 56Ac and the upper surface of the flow path block to enhance the effect of preventing the male terminal 303 and the connector portion 304 from coming off.

[0069] When the motor-operated valve 1A is lowered relative to the flow path block PBA in order to attach the valve body 2 of the motor-operated valve 1A to the attachment opening OP, the male terminal 303 and the connector portion 304 are inserted into the hollow cylindrical portion 58b, and the male terminal 303 can be engaged with the female terminal 108 so as to be able to transmit signals. This allows the detection signals generated by the pressure / temperature sensors to be input to the microcomputer 101.

[0070] The inner diameter of the hole HL is smaller than the outer diameter of the connector portion 304, thereby preventing the connector portion 304 from slipping out of the hole HL. In addition, the entire circumference of the lower end of the hollow cylindrical portion 56Ac abuts against the upper surface of the flow path block PBA, preventing external foreign matter from passing between the abutting surfaces and entering the interior.

[0071] 5 is a longitudinal cross-sectional view of an electric valve 1B according to a second modification. The electric valve 1B of this modification differs from the embodiment described above only in the cover member 58B, the main board 100B, and the pressure / temperature sensors. The other components are the same as those of the embodiment described above, and therefore the same reference numerals are used and redundant description will be omitted.

[0072] The main board 100B is different in that it has male terminals (first terminals) 108B instead of female terminals, but the other configuration is the same as the above-mentioned embodiment, so a duplicated description of the common configuration will be omitted. Furthermore, the pressure / temperature sensor (not shown in FIG. 5) is different in the configuration around the connector portion 304D, but the other configuration is the same as the above-mentioned embodiment, so a duplicated description of the common configuration will be omitted.

[0073] A portion of the outer periphery of the resin molded cover 56 protrudes radially outward, forming a hollow housing portion 56a, the opening of which is shielded by a lid member 58B. The lid member 58B has a plate portion 58Ba that covers the opening of the housing portion 56a, and a rectangular tube portion (first connector) 58Bb that protrudes outward from the plate portion 58Ba. The rectangular tube portion 58Bb has a protrusion 58Bc on its outer periphery.

[0074] On the main board 100B, a male terminal 108B connected to the microcomputer 101 (FIG. 1) is disposed opposite the rectangular tube portion 58Bb.

[0075] A female terminal (second terminal) 303D is attached to the tip of a wire 302 extending from the pressure / temperature sensor, and a connector portion (second connector) 304D in the shape of a bottomed square tube is fixed around the periphery of the female terminal 303D. The wire 302 passes through the bottom wall of the connector portion 304D, and a through-hole 305D corresponding to the protrusion 58Bc is formed in the peripheral wall of the connector portion 304D. The protrusion 58Bc and the through-hole 305D constitute a prevention device.

[0076] When the connector portion 304D is fitted into the rectangular tube portion 58Bb, the inner periphery of the connector portion 304D comes into close contact with the outer periphery of the rectangular tube portion 58Bb, and the female terminal 303D can be engaged with the male terminal 108B in a signal-transmitting manner, thereby inputting the detection signal generated by the pressure / temperature sensor 300D to the microcomputer 101. Furthermore, by pushing the connector portion 304D into the rectangular tube portion 58Bb, the protrusion 58Bc fits into the through-hole 305D, thereby preventing the rectangular tube portion 58Bb from slipping out of the connector portion 304D. Similar prevention devices can be installed in the above-mentioned embodiments and modifications.

[0077] This specification includes the disclosure of the following inventions. a valve element that is axially movable toward and away from the valve seat; a feed screw mechanism that converts rotational movement of the rotor into axial movement of the valve element; and a substrate that is disposed within the cover and has a control unit connected to a first terminal; wherein the sensor has flexible wiring that can transmit a detection signal, a second terminal connected to the wiring, and a second connector that can be connected to the first connector; and when the first connector and the second connector are connected, the first terminal and the second terminal engage to be able to transmit a signal; and the control unit obtains the detection signal from the sensor via the first terminal and the second terminal, and generates a drive signal to drive the motor based on the detection signal.

[0078] (Second Aspect) The motor-operated valve of the first aspect, characterized in that the motor-operated valve constitutes a part of a refrigeration cycle using the fluid as a refrigerant, and the control unit sends the detection signal input from the sensor to a system ECU of the refrigeration cycle.

[0079] (Third Aspect) The motor-operated valve according to the first or second aspect, wherein the first terminal is connectable to the second terminal of one or more sensors among a plurality of sensors.

[0080] (Fourth Aspect) The motor-operated valve according to any one of the first to third aspects, wherein the second connector is coupled to the first connector in a state where the second connector is inserted into the first connector.

[0081] (Fifth Aspect) The motor-operated valve according to any one of the first to third aspects, wherein the first connector is coupled to the second connector in a state where the first connector is inserted into the second connector.

[0082] (Sixth Aspect) The motor-operated valve of the fourth aspect, characterized in that, when the motor-operated valve is attached to a flow path block having a flow path through which the fluid flows, the connecting portion of the first connector is arranged to face the flow path block side.

[0083] (Seventh Aspect) The motor-operated valve according to any one of the first to sixth aspects, further comprising a prevention device that prevents the first connector and the second connector from separating after the first connector and the second connector are connected.

[0084] (Eighth Aspect) An electric valve unit having a sensor that detects at least one of the pressure and temperature of a fluid flowing into or out of the electric valve, and an electric valve to which a detection signal can be input from the sensor, wherein the sensor has: a flexible wiring that can transmit a detection signal; a second terminal connected to the wiring; and a second connector, wherein the electric valve has: a valve body having a valve port and a valve seat surrounding the valve port; a cylindrical can attached to the valve body; a rotor disposed inside the can; a stator disposed outside the can; a cover that covers the stator and has a first connector that can be connected to the second connector; a valve element that is movable in an axial direction toward and away from the valve seat; a feed screw mechanism that converts rotational movement of the rotor into axial movement of the valve element; and a substrate that is disposed within the cover and has a control unit and a first terminal connected to the control unit, wherein when the first connector is connected to the second connector, the first terminal and the second terminal engage to be able to transmit a signal, the control unit receives a detection signal from the sensor via the first terminal and the second terminal, and generates a drive signal for driving the motor based on the detection signal.

[0085] REFERENCE SIGNS LIST 1, 1A, 1B Motor-operated valve 2 Valve body 3 Can 4 Valve element 5 Stepping motor 6 Reduction mechanism 7 Output shaft 8 Shaft member 9 Feed screw mechanism 58b, 56Ac Hollow cylindrical portion 58Bb Square cylindrical portion 61 Sun gear 62 Fixed ring gear 63 Planetary gear 64 Carrier 65 Output gear member 100 Main circuit board 108 Female terminal 108B Male terminal 106 Sub-circuit board 200 Solenoid valve 300, 300A, 300B, 300C, 300D Pressure / temperature sensor 303 Male terminal 303D Female terminal 304, 304D Connector portion 400 ECU

Claims

1. An electric valve that can receive a detection signal from a sensor that detects at least one of the pressure and temperature of a fluid flowing into or out of the electric valve, comprising: a valve body having a valve orifice and a valve seat surrounding the valve orifice; a cylindrical can attached to the valve body; a rotor arranged inside the can; a stator arranged outside the can; a cover that covers the stator and has a first connector; a valve body that is movable in the axial direction toward and away from the valve seat; a feed screw mechanism that converts the rotational movement of the rotor into the axial movement of the valve body; and a substrate that is arranged within the cover and has a control unit connected to a first terminal; the sensor has flexible wiring that can transmit a detection signal, a second terminal connected to the wiring, and a second connector that can be connected to the first connector; when the first connector and the second connector are connected, the first terminal and the second terminal engage to be able to transmit a signal; and the control unit obtains the detection signal from the sensor via the first terminal and the second terminal, and generates a drive signal to drive the motor based on the detection signal.

2. The motor-operated valve according to claim 1, characterized in that the motor-operated valve constitutes part of a refrigeration cycle using the fluid as a refrigerant, and the control unit sends the detection signal input from the sensor to a system ECU of the refrigeration cycle.

3. The motor-operated valve according to claim 1, characterized in that the first terminal is connectable to the second terminal of one or more sensors among a plurality of sensors.

4. The motor-operated valve according to claim 1, characterized in that the second connector is connected in a state in which it is inserted into the first connector.

5. The motor-operated valve according to claim 1, characterized in that the first connector is connected in a state in which it is inserted into the second connector.

6. The motor-operated valve according to claim 4, characterized in that, when the motor-operated valve is attached to a flow path block having a flow path through which the fluid flows, the connecting portion of the first connector is arranged to face the flow path block side.

7. The motor-operated valve according to any one of claims 1 to 6, characterized in that a prevention device is provided to prevent the first connector and the second connector from separating after the first connector and the second connector are connected.

8. An electric valve unit having a sensor that detects at least one of the pressure and temperature of a fluid flowing into or out of an electric valve, and an electric valve to which a detection signal can be input from the sensor, wherein the sensor has: a flexible wiring capable of transmitting a detection signal; a second terminal connected to the wiring; and a second connector, wherein the electric valve has: a valve body having a valve orifice and a valve seat surrounding the valve orifice; a cylindrical can attached to the valve body; a rotor disposed inside the can; a stator disposed outside the can; a cover covering the stator and having a first connector connectable to the second connector; a valve body that is movable in the axial direction toward and away from the valve seat; a feed screw mechanism that converts the rotational movement of the rotor into axial movement of the valve body; and a substrate that is disposed within the cover and has a control unit and a first terminal connected to the control unit, wherein when the first connector and the second connector are connected, the first terminal and the second terminal engage to be able to transmit a signal, the control unit acquires a detection signal from the sensor via the first terminal and the second terminal, and generates a drive signal for driving the motor based on the detection signal.

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