Motor-operated valve

Abstract

To provide a motor valve for actualizing winding breakage prevention during molding and securing the strength of the molded part at the same time, while arranged a coil in a stator in a precise manner.SOLUTION: A motor valve includes a valve body having a valve chamber communicated with an inflow path for refrigerant and an outflow path for the refrigerant, a valve element for changing the flow amount of the refrigerant, a motor for driving the valve element, a circuit board for controlling the motor, a case storing the circuit board, an outer shell coating molded part for covering the stator of the motor, and a coil coating molded part 41 provided inside the outer hell molded part for covering the coil of the motor. It further includes a rough part 64 provided in the coil coating molded part for positioning the coil coating molded part in the outer shell molded part.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an electrically operated valve in which a valve element is driven by an electric motor. [Background technology]

[0002] Electric valves, which use an electric motor such as a stepping motor to control the valve opening, have traditionally been used in refrigeration cycle equipment equipped with a refrigerant circuit, such as air conditioners and refrigerators / freezers.

[0003] Another example of such an electrically operated valve is one equipped with a controller that controls the excitation current of the coil. The controller is mounted on a printed circuit board, and this board (referred to herein as a "control board" or simply "board") is housed in a resin case provided close to the stator. Furthermore, the coil and stator of the electric motor are covered with resin.

[0004] Furthermore, the following Patent Document 1 is a document that discloses such a motor-operated valve. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2021-110409 Summary of the Invention [Problem to be solved by the invention]

[0006] Incidentally, in the case of the motor-operated valve described above, when resin molding is performed to cover the coil and stator with resin, the coil is susceptible to deformation and damage such as poor insulation and broken wires due to the pressure of the resin during molding, so it is preferable to perform molding at low pressure.

[0007] On the other hand, the stator portion (the portion outside the coil coating molding portion; the same applies below) generally has a complex shape, and molding it at low pressure may result in voids and a decrease in strength, so it is preferable to mold it at high pressure.

[0008] When the coil and stator are covered with resin in this way, there are conflicting problems.

[0009] On the other hand, to solve the above problems, it is possible to use a two-stage molding process (i.e., a double coating structure). That is, the coil coating molding part that covers the coil is molded at low pressure, and then the stator part that covers this is molded at high pressure, thereby preventing damage to the winding during molding and ensuring the strength of the molding part at the same time.

[0010] However, when molding the stator portion under high pressure, it is not necessarily easy to accurately hold the coil covered by the coil covering molding portion within the mold and to accurately position the coil within the stator.

[0011] Therefore, an object of the present invention is to simultaneously prevent damage to the coil winding during molding, ensure the strength of the molded portion, and enable the coil to be positioned accurately within the stator. [Means for solving the problem]

[0012] In order to solve the above problems and achieve the object, the motor-operated valve according to the present invention comprises a valve body having a valve chamber communicating with an inlet passage for introducing a refrigerant and an outlet passage for discharging the refrigerant, a valve element that changes the flow rate of the refrigerant by moving back and forth relative to a valve seat in the valve chamber between a closed valve state in which it is seated on a valve seat and an open valve state in which it is separated from the valve seat, an electric motor that drives the valve element, a control board on which electronic components that control the electric motor are mounted, a board accommodating section including a case section that accommodates the control board, an outer shell molding section that covers a stator of the electric motor, and a coil covering molding section that is provided inside the outer shell molding section and covers a coil of the electric motor, By positioning the coil covering molding part in the mold for molding the outer shell molding part, Positioning the coil cover mold within the shell mold to make it possible The coil coating molding part was provided with a concave and convex portion.

[0013] In the motor-operated valve according to the present invention, a coil covering molding portion that covers the coil provided inside the stator is provided inside the stator. This structure, which uses a two-stage molding process (i.e., a double-cover structure), prevents damage to the coil windings during molding and also avoids the occurrence of voids in the stator portion (the portion outside the coil covering molding portion; the same applies below) that would otherwise reduce strength due to the complex shape of the stator. Specifically, by molding the coil covering molding portion, which is prone to deformation and damage such as poor insulation and breakage due to the pressure of the resin during molding, at low pressure, and then molding the stator portion that covers it at high pressure, it is possible to simultaneously prevent damage to the windings during molding and ensure the strength of the molding portion.

[0014] Furthermore, it is preferable to mold the stator portion by introducing resin through a single gate (inlet) to prevent weld lines that would reduce strength. This is to prevent cracks in the weld lines due to temperature changes over time and other factors, allowing moisture to seep in. On the other hand, if the above-mentioned double-coating structure (a structure with a coil coating molding part inside the stator) is adopted, the coil coating molding part, which can ensure strength by being located inside the stator, does not need to be a major consideration for strength. Therefore, by introducing resin through multiple gates, it is possible to more reliably cover the coil, which has a complex shape.

[0015] Furthermore, in adopting the above-described double coating structure, the coil coating molding part is provided with an uneven portion for positioning the coil coating molding part within the stator. This is to improve the positioning accuracy of the coil (coil molding part) within the stator by enabling the coil covered by the coil coating molding part to be accurately positioned within the mold that forms the stator using the uneven portion when molding the stator.

[0016] The "concave and convex portions" can be concave portions, such as holes (preferably a plurality of holes), but may also be convex portions such as protrusions (preferably a plurality of protrusions).

[0017] In addition, the present invention Another motor-operated valve is, a valve body having a valve chamber communicating with an inlet passage for introducing a refrigerant and an outlet passage for discharging the refrigerant; a valve element that changes the flow rate of the refrigerant by moving back and forth relative to a valve seat in the valve chamber between a closed state in which it is seated on the valve seat and an open state in which it is separated from the valve seat; an electric motor that drives the valve element; a control board on which electronic components that control the electric motor are mounted; a board accommodating section including a case that accommodates the control board; an outer shell molding section that covers a stator of the electric motor; and a coil covering molding section that is provided inside the outer shell molding section and covers a coil of the electric motor. The connector includes an external connection terminal that allows electrical connection to the outside, and a terminal covering molding portion that covers an intermediate portion of the external connection terminal to support the external connection terminal in the connector. It is an electrically operated valve , The coil covering molding part is provided with a concave / convex part that enables the coil covering molding part to be positioned within the outer shell molding part by positioning the coil covering molding part within the mold that integrally molds the outer shell molding part and the connector part, and the terminal covering molding part is positioned within the mold that integrally molds the outer shell molding part and the connector part. Positioning the terminal coating molding part inside the connector part to make it possible The terminal covering molding portion has a concave and convex portion.

[0018] the above Another motor-operated valve is , In addition to the features of the motor-operated valve according to the present invention, by positioning the terminal cover molding part in the mold that integrally molds the outer shell molding part and the connector part, Positioning the terminal coating molding part inside the connector part to make it possible The terminal cover molding has a concave and convex portion. Integrated with the outer shell molding When molding, the external connection terminals covered by the terminal covering molding part are molded using the concave and convex parts. Outer shell molding part and Connector part together It can be accurately positioned in the molding die, and the external connection terminals can be installed in the connector section with high positional accuracy. Provided in the terminal coating molding section The "uneven portion" can be a concave portion, for example, a hole (preferably a plurality of holes), but may also be a convex portion such as a protrusion (preferably a plurality of protrusions). [Effects of the Invention]

[0019] According to the present invention, it is possible to simultaneously prevent damage to the coil winding during molding and ensure the strength of the molded portion, and also to accurately position the coil within the stator.

[0020] Other objects, features, and advantages of the present invention will become apparent from the following description of the preferred embodiments of the present invention, which is given with reference to the accompanying drawings. It will be apparent to those skilled in the art that the present invention is not limited to the following embodiments, and that various modifications can be made within the scope of the claims. In addition, the same reference numerals in the various drawings indicate the same or equivalent parts. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 1 is a vertical cross-sectional view showing a motor-operated valve according to a first embodiment of the present invention in a closed state. [Figure 2]FIG. 2 is a vertical cross-sectional view showing the motor-operated valve according to the first embodiment in an open state. [Figure 3] FIG. 3 is a perspective view showing a manufacturing process of the motor-operated valve according to the first embodiment, showing a state in which a coil cover that covers the coil has been molded (a state after primary molding has been completed). [Figure 4] FIG. 4 is a perspective view showing the manufacturing process of the motor-operated valve according to the first embodiment, showing the state in which a coil with a molded coil cover and an external connection terminal with a molded terminal cover are placed in a mold (not shown) for molding the outer shell cover. [Figure 5] Figure 5 is a front view showing the manufacturing process of the motor-operated valve according to the first embodiment, showing the state in which a coil with a molded coil cover and an external connection terminal with a molded terminal cover are placed in a mold (not shown) for molding the outer shell cover. [Figure 6] FIG. 6 is a longitudinal cross-sectional view showing the manufacturing process of the motor-operated valve according to the first embodiment, showing a coil with a molded coil cover and an external connection terminal with a molded terminal cover, as viewed from the side, arranged in a mold (not shown) for molding the outer shell cover. [Figure 7] FIG. 7 is a perspective view showing a manufacturing process of the motor-operated valve according to the first embodiment, showing the state before the substrate is attached inside the case. [Figure 8] FIG. 8 is a perspective view showing a manufacturing process of the motor-operated valve according to the first embodiment, showing a state in which a substrate is attached inside a case. [Figure 9] FIG. 9 is a perspective view showing a manufacturing process of the motor-operated valve according to the first embodiment, showing a state in which the cover is welded to the case. [Figure 10] FIG. 10 is an enlarged vertical cross-sectional view showing the relationship between the fixing hole of the base plate, the press-fit projection of the case, and the pressing projection of the cover in the motor-operated valve according to the first embodiment. [Figure 11] FIG. 11 is a front view showing the relationship between the fixing holes of the substrate and the press-fit protrusions of the case in the motor-operated valve according to the first embodiment. [Figure 12]FIG. 12 is an enlarged vertical cross-sectional view showing the relationship between the fixing hole of the base plate, the loose-fitting protrusion of the case, and the pressing protrusion of the lid body in the motor-operated valve according to the first embodiment. [Figure 13] FIG. 13 is a cross-sectional view showing a manufacturing process of the motor-operated valve according to the first embodiment, showing the state before the substrate is attached inside the case. [Figure 14] FIG. 14 is a cross-sectional view showing a manufacturing process of the motor-operated valve according to the first embodiment, showing a state where the support protrusion of the case has just begun to be inserted into the fixing hole of the substrate. [Figure 15] FIG. 15 is a cross-sectional view showing a manufacturing process of the motor-operated valve according to the first embodiment, showing a state in which the support protrusion has been inserted into the fixing hole of the substrate and the terminal has begun to be inserted into the through-hole. [Figure 16] FIG. 16 is a cross-sectional view showing a manufacturing process of the motor-operated valve according to the first embodiment, showing a state in which the terminal has been inserted into the through-hole and the support protrusion has begun to be press-fit into the fixing hole. [Figure 17] FIG. 17 is a cross-sectional view showing a manufacturing process of the motor-operated valve according to the first embodiment, showing a state where the support protrusion has been press-fit into the fixing hole. [Figure 18] FIG. 18 is a cross-sectional view showing a manufacturing process of the motor-operated valve according to the first embodiment, showing the state before the cover is attached. [Figure 19] FIG. 19 is a cross-sectional view showing a manufacturing process of the motor-operated valve according to the first embodiment, showing a state in which the lid is brought into contact with the front edge of the case. [Figure 20] FIG. 20 is a cross-sectional view showing a manufacturing process for the motor-operated valve according to the first embodiment, showing a state in which the cover has been welded to the case and attachment of the cover has been completed. [Figure 21] FIG. 21 is a front view showing a manufacturing process of the motor-operated valve according to the first embodiment, showing the state before the lid is attached to the case. [Figure 22] FIG. 22 is a vertical cross-sectional view showing a closed state of the motor-operated valve according to the second embodiment of the present invention. [Figure 23]FIG. 23 is a vertical cross-sectional view showing the motor-operated valve according to the second embodiment in an open state. [Figure 24] FIG. 24 is a perspective view showing a manufacturing process of the motor-operated valve according to the second embodiment, showing the state before the substrate is attached inside the case. [Figure 25] FIG. 25 is a perspective view showing a manufacturing process of the motor-operated valve according to the second embodiment, showing a state in which a substrate is attached inside a case. [Figure 26] FIG. 26 is a perspective view showing a manufacturing process for the motor-operated valve according to the second embodiment, showing a state in which the cover is attached to the case. DETAILED DESCRIPTION OF THE INVENTION

[0022] [First embodiment] A motor-operated valve according to a first embodiment of the present invention will be described with reference to Figures 1 to 21. In each figure, mutually orthogonal two-dimensional or three-dimensional coordinates representing the front-rear, left-right, and up-down directions are appropriately displayed, and the following description will be based on these directions (the same applies to the second embodiment described below).

[0023] The motor-operated valve 11 according to the first embodiment of the present invention is an motor-operated valve suitable for use in adjusting the flow rate of a refrigerant in a refrigeration cycle device such as an air conditioner. The motor-operated valve 11 comprises a valve body 12 having a valve chamber 13 therein, an inlet passage 16 for introducing a refrigerant into the valve chamber 13, and an outlet passage 15 for discharging the refrigerant from the valve chamber 13, a valve seat 14 formed at the opening of the inlet passage 16 to the valve chamber 13, and a valve seat 14 which moves back and forth (up and down) relative to the valve seat 14 between a closed state in which the valve seat 14 abuts against the valve seat 14 (see FIG. 1 ) and an open state in which the valve seat 14 is spaced apart from the valve seat 14 (see FIG. 2 ) to adjust the amount of refrigerant passing through (flow rate). the valve body 12 includes a valve element 17 that changes the direction of flow of the refrigerant, an electric motor 23 that drives the valve element 17, a connecting member 19 that connects the electric motor 23 to the valve body 12, a printed circuit board (control board) 46 on which a controller (not shown) that controls the electric motor 23 is mounted, a case (board housing section / case section) 43 that houses the circuit board 46, a lid 47 that closes the front opening of the case 43, a connector 44 having external connection terminals 45 for electrical connection to the outside, and a can (sealed container) 22 that covers the upper opening 12a of the valve body 12 that communicates with the valve chamber 13 and forms a sealed space together with the connecting member 19. In this embodiment, the refrigerant flows in through the inlet path 16 and flows out through the outlet path 15, but the motor-operated valve 11 can of course be used even if the refrigerant flows in the opposite direction.

[0024] The electric motor 23 is a stepping motor equipped with a stator 25 arranged outside the can 22 and a magnet rotor (hereinafter simply referred to as "rotor") 24 arranged rotatably and vertically slidably inside the can 22. The stator 25 includes a yoke 26, a bobbin 27, and a coil 28.

[0025] The stator 25 and the can 22 are covered by an outer shell cover (outer shell molding portion) 42 made of synthetic resin. Inside the outer shell cover 42, there are provided a coil cover (coil covering molding portion) 41 made of synthetic resin that covers the coil 28, and a terminal cover (terminal covering molding portion) 63 that covers and supports the middle portion of the external connection terminal 45.

[0026] The external connection terminal 45 has a tip portion (connector side end) 45a that protrudes into the internal space 44a of the connector 44 to enable electrical connection with the outside, and a base portion (board side end) 45b that is electrically connected to the board 46, and the intermediate portion between the tip portion 45a and the base portion 45b is covered by a terminal cover 63.

[0027] Furthermore, the above-mentioned covers (coil cover 41, terminal cover 63, and outer shell cover 42) are formed by injection molding, but the molding process is carried out in the following order: first, coil cover 41 and terminal cover 63 (in Figures 1 and 2, the cross section of each cover 41, 63 has a fine dot pattern) are molded separately (this process is called "primary molding"), and then outer shell cover 42 (in Figures 1 and 2, the cross section of each cover 41, 63 has a coarse dot pattern) is molded to cover each cover (coil cover 41 and terminal cover 63) (this process is called "secondary molding").

[0028] Here, in the primary molding, positioning recesses to be used when the secondary molding is performed are formed in each of the coil cover and the terminal cover.

[0029] 3 shows the coil after primary molding in an inverted state so that the underside of coil cover 41 is visible, and as shown in the figure, in the primary molding, multiple (four in this embodiment) notched recesses 64 are formed on the inner peripheral edge of the bottom surface of coil cover 41 as positioning recesses. Also, FIGS. 4 to 6 show the coil (covered by coil cover 41) and external connection terminals 45 (their intermediate portions are covered by terminal cover 63) after primary molding placed in a mold 66 that forms outer shell cover 42, and multiple (three in this embodiment) holes 65 are formed in terminal cover 63 as positioning recesses. Furthermore, mold 66 that forms outer shell cover 42 is provided with engaging portions (e.g., engaging protrusions, not shown) therein that engage with the notched recesses and holes, respectively.

[0030] Therefore, according to this embodiment, the use of positioning recesses 64, 65 makes it possible to accurately position coil 28 covered with coil cover 41 and external connection terminals 45 equipped with terminal cover 63 within mold 66 for outer shell cover 42, making it possible to install coil 28 and external connection terminals 45 within outer shell cover 42 while accurately maintaining the relative positional relationship between coil 28 and external connection terminals 45. Furthermore, in this embodiment, because multiple positioning recesses 64, 65 are provided in each of coil cover 41 and terminal cover 63, coil 28 and external connection terminals 45 can be more accurately positioned within mold 66 for secondary molding, making it possible to more reliably prevent misalignment of coil 28 and external connection terminals 45 due to resin flowing into mold 66 during secondary molding.

[0031] During secondary molding, the box-shaped case 43 that houses the substrate 46 and the connector 44 are molded integrally with the outer shell cover 42. Note that the resin materials that make up the coil cover 41, the terminal cover 63, the outer shell cover 42 (including the case 43 and the connector 44), and the lid body 47 (described later) can each be different materials, but it is preferable to use the same material to improve the bondability between the resins.

[0032] In this embodiment, the case 43 is provided on the side (front) of the stator 25, and the connector 44 is provided on the top surface of the case 43. A circuit board 46 is housed in the interior 43a of the case 43 through the front opening of the case 43, and the coil 28 is electrically connected to the external connection terminal 45 via the circuit board 46. This is to enable power to be supplied to the coil 28 from an external power source (not shown). A controller including a pulse generator and a motor drive circuit is also mounted on the circuit board 46. Furthermore, if the motor-operated valve 11 is equipped with a magnetic sensor that detects the rotation of the rotor 24, a calculation device that calculates the rotation angle of the rotor 24 and the valve opening based on the output signal from the magnetic sensor may be mounted on the circuit board 46.

[0033] The case 43 and the connector 44 each have a sealable structure. Specifically, when a mating connector is mated to the front end of the connector 44, the interior 44a of the connector 44 is sealed. The mating connector is a connector of a specific shape that can be mated and connected to the connector of the motor-operated valve. That is, connectors are generally manufactured to have a specific (predetermined, fixed, user-specific) shape that is tailored to (compatible with) the user of the motor-operated valve, and when a mating connector of such a specific shape is mated, the connector is sealed. Note that the sealed state refers to a state in which moisture does not penetrate into the interior 44a of the connector 44 during normal use of the motor-operated valve 11, and in this embodiment, the interior 44a of the connector 44 is isolated from the external space (the atmosphere side).

[0034] On the other hand, the case 43 is sealed by welding a resin cover 47 to the front opening to close the front opening. The attachment of the cover to the case will be described in detail later, along with the support structure for the circuit board.

[0035] The motor-operated valve 11 of this embodiment is equipped with a rod-shaped valve stem 18 that extends vertically along the central axis A from the inside of the rotor 24 to the valve chamber 13. The valve stem 18 has a cylindrical body 18a and an upper small-diameter section 18b with a small outer diameter that is formed coaxially at the upper end of the body 18a and continues from the body 18a. The valve stem 18 (body 18a) is also equipped with a valve element 17 integrally at its lower end. The rotor 24 is disposed inside the can 22 so as to be rotatable and slidable in the vertical direction, and the valve is opened and closed by the vertical movement of the valve stem 18, which has the valve element 17 at its lower end, and the rotor 24.

[0036] A valve stem holder 31 is provided inside the rotor 24. The valve stem holder 31 has a cylindrical shape with a closed upper end, and a support ring 33 is fixed to the upper end of the valve stem holder 31 by crimping. The rotor 24 and valve stem holder 31 are joined together via the support ring 33. A female thread 31a is formed on the inner peripheral surface of the valve stem holder 31. This female thread 31a is threadedly engaged with a male thread 36c of a guide bush 36 (described later) to form a transmission mechanism (screw feed mechanism) that converts the rotation of the electric motor 23 into linear motion and transmits it to the valve stem 18.

[0037] The upper small-diameter portion 18b of the valve stem 18 passes through the valve stem holder 31, and a push nut 34 is attached to the upper end of the upper small-diameter portion 18b to prevent it from coming off. The valve stem 18 is urged downward by a compression coil spring 35 provided between the valve stem holder 31 and a step between the body portion 18a and the upper small-diameter portion 18b of the valve stem 18. Therefore, the push nut 34 and the compression coil spring 35 restrict the valve stem 18 from moving up and down relative to the valve stem holder 31, and the valve stem 18 moves up and down together with the valve stem holder 18.

[0038] The connecting member 19 is a cylindrical member having a large diameter hole 19a and a small diameter hole 19b that are through holes that communicate with each other. The large diameter hole 19a passes through the upper center of the connecting member 19 and has a large diameter so that a guide bush 36 (described later) can be inserted from above. The small diameter hole 19b passes through the lower center of the connecting member 19 and has a small diameter. A cylindrical can 22 with no bottom and a lid (an open bottom and a closed top) is joined to the outer circumferential surface of the upper end of the connecting member 19 via a ring-shaped base plate 21.

[0039] A guide bush 36 is fixed in the large-diameter hole 19a at the top of the connecting member 19. The guide bush 36 has a large-diameter cylindrical portion 36a with a large outer diameter and a small-diameter cylindrical portion 36b with a small outer diameter formed coaxially at the upper end of the large-diameter cylindrical portion 36a, continuing from the large-diameter cylindrical portion 36a. A male thread portion 36c that screws into the female thread portion 31a of the valve stem holder 31 is formed on the outer circumferential surface of the small-diameter cylindrical portion 36b. The guide bush 36 is coupled to the connecting member 19 by press-fitting the large-diameter cylindrical portion 36a into the inside of the connecting member 19. The body portion 18a of the valve stem 18 passes through the small-diameter hole 19b of the connecting member 19.

[0040] Furthermore, the stem holder 31 is provided with an upper stopper body 32, while the large-diameter cylindrical portion 36a of the guide bush 36 is provided with a lower stopper body 37. These stopper bodies 32, 37 determine the lower limit position of the stem holder 31. When the stem holder 31 rotates and descends to reach the lower limit position, the upper stopper body 32 abuts against the lower stopper body 37, restricting further rotation of the stem holder 31.

[0041] The mechanism for transmitting the driving force of the electric motor 23 to the valve element 17 may be of various types other than those described above, and is not limited to the above structure.

[0042] The operation of the motor-operated valve 11 according to this embodiment will be described as follows.

[0043] 1, when current is supplied to the stator 25 (coil 28) so that the rotor 24 rotates in one direction, the stem holder 31 connected to the rotor 24 rotates together with the rotor 24. The inner peripheral surface of the stem holder 31 is formed with a female thread 31a that screws together with a male thread 36c formed on the outer peripheral surface of the small-diameter cylindrical portion 36b of the guide bush 36. The interaction between the male thread 36c and the female thread 31a converts the rotation of the rotor 24 (stem holder 31) into linear motion in the vertical direction, causing the stem holder 31 to move upward. As a result, the rotor 24 connected to the stem holder 31 and the stem 18, whose relative movement between them is restricted, also move upward together with the stem holder 31. As the valve stem 18 moves upward, the valve element 17 attached to the lower end of the valve stem 18 moves away from the valve seat 14, and the refrigerant that has flowed in from the inlet passage 16 passes through the valve chamber 13 and flows out from the outlet passage 15 (see Figure 2). The amount of refrigerant passing through (refrigerant flow rate) can be adjusted by the amount of rotation of the rotor 24.

[0044] On the other hand, when current is supplied to the stator 25 (coil 28) so that the rotor 24 rotates in the opposite direction from the open valve state, the interaction between the female thread portion 31a and the male thread portion 36c converts the rotation of the rotor 24 (valve stem holder 31) into linear motion in the vertical direction, and the valve stem holder 31 moves downward together with the rotor 24 and valve stem 18. This causes the valve element 17 to descend toward the valve seat 14, and when the valve element 17 abuts against the valve seat 14, the flow path between the inlet path 16 and the outlet path 15 is blocked, resulting in a closed valve state (see Figure 1).

[0045] 7 to 21, the support structure of the substrate 46 on the case 43 and the attachment of the lid 47 will be described.

[0046] In this embodiment, the means for supporting the substrate 46 inside the case 43 include support protrusions 51, 58 molded integrally with the case 43, a fixing hole 67 drilled in the substrate 46, and a pressing protrusion 61 formed on the back surface (inner surface) of the lid body 47 that closes the front opening of the case 43. The support protrusions 51, 58 inserted into the fixing hole 67 restrict horizontal movement of the substrate 46, and the step portions 57 provided on the support protrusions 51, 58 and the pressing protrusion 61 clamp the substrate 46 to restrict vertical movement of the substrate 46, thereby supporting the substrate 46 inside the case 43.

[0047] To describe each means in detail, the interior of case 43 is provided with a plurality of (four in this embodiment) support protrusions 51, 58 that rise vertically (forward) from the bottom surface of case 43. Furthermore, substrate 46 is provided with a plurality of (four in this embodiment to correspond to the support protrusions) fixing holes 67 into which support protrusions 51, 58 are fitted. Furthermore, the back surface (inner surface) of lid 47 that closes the front opening of case 43 is provided with pressing protrusions 61 that come into contact with the surface of substrate 46 when substrate 46 is placed inside case 43 and lid 47 is joined to case 43.

[0048] The support protrusions 51, 58 consist of two press-fit protrusions (press-fit type protrusions) 51 and two loose-fit protrusions (loose-fit type protrusions) 58. These support protrusions 51, 58 are molded integrally with the case 43 by the secondary molding that forms the outer shell cover 42. In addition, step portions 57 that extend horizontally outward from the periphery of the fixing hole 67 are formed on the bottom surfaces of the support protrusions 51, 58. When the support protrusions 51, 58 are inserted into the fixing hole 67 and the board 46 is advanced toward the bottom surface of the case 43, the back surface of the board 46 abuts against these step portions 57, stopping the advancement of the board 46 (receiving the back surface of the board 46), and functioning to clamp the board 46 in cooperation with the pressing protrusion 61 formed on the back surface of the lid 47.

[0049] 10 and 11, the press-fit projection 51 has a generally cylindrical projection main body 51a and a protruding ridge portion 55 that protrudes outward from the outer circumferential surface of the projection main body 51a. The protruding ridge portion 55 extends in the vertical direction (front-to-back direction), which is the length direction of the press-fit projection 51, and has a triangular cross-sectional shape (see FIG. 11) that is pointed outward from the outer circumferential surface of the projection main body 51a.

[0050] The ridge portion (the vertex of the triangle when viewed in cross section) 56 of the convex rib portion 55 protrudes outward from the inner surface of the fixing hole 67 of the substrate 46, and when the portion (this portion is called the "press-in portion") 53 forming the convex rib portion 55 in the longitudinal direction of the press-in protrusion 51 is inserted into the fixing hole 67 of the substrate 46, the ridge portion (the hatched portion in Figure 11) 53 of the convex rib portion 55 is crushed within the fixing hole 67, thereby fixing the press-in protrusion 51 within the fixing hole 67.

[0051] Each press-fit projection 51 is formed with a plurality of (three in this embodiment) ridge portions 55, and these three ridge portions 55 are arranged radially with respect to the central axis B of the press-fit projection 51 (so that the angles formed by adjacent ridge portions 55 are equal, i.e., 120° in this embodiment). This is to prevent the substrate 46 from shifting sideways due to a horizontal force applied by the ridge portions 55 when the press-fit projection 51 is press-fitted into the fixing hole 67 of the substrate 46, and to stably support the substrate 46 within the case 43. The number of ridge portions 55 may be, for example, four, two or less, or five or more.

[0052] Furthermore, the tip (front end) of the protrusion main body 51a is formed as a small-diameter section 52 with a small outer diameter to facilitate insertion into the fixing hole 67 of the substrate 46, and a tapered surface 54 is formed so that the outer diameter gradually increases from the small-diameter section 52 to the press-fit section 53. This is to smoothly guide the substrate 46 (fixing hole 67) into the press-fit section 53. In addition, in accordance with the tapered surface 54, the front end (tip in the length direction) of the convex rib section 55 is also tapered so that the height of the ridge section 56 gradually increases toward the rear.

[0053] 12, the loose-fitting projection 58 has a step 57 on its bottom surface that functions similarly to the step 57 of the press-fit projection 51, and has a cylindrical projection main body 58a that rises vertically (forward) from the step 57. The projection main body 58a has an outer diameter dimension that forms a certain gap S between it and the inner circumferential surface of the fixing hole 67 of the substrate 46.

[0054] The support protrusions 51, 58 are arranged at the four corners of the case 43 having a rectangular front shape, more specifically, the press-fit protrusions 51 are arranged at both ends of one diagonal of the case 43, and the loose-fit protrusions 58 are arranged at both ends of the other diagonal of the case 43. Note that it is also possible for all of the support protrusions 51, 58 to be press-fit protrusions 51, but if all were press-fit protrusions 51, high dimensional accuracy would be required for the relative positional relationship between the support protrusions 51 and the fixing holes 67, as described above, which would increase manufacturing costs, and there is also a concern that the support protrusions 51 may be subjected to force when the board is attached or to vibrations when mounted on a vehicle and used over time, which could cause damage to the support portion of the board 46, such as breaking the support protrusions 51. Therefore, in this embodiment, the loose-fit protrusions 58 are included.

[0055] The pressing protrusion 61 on the back surface of the lid 47 has a cylindrical shape that can accommodate the tips of the support protrusions 51, 58. The height (lengthwise dimension) of the pressing protrusion 61 is set so that when the lid 47 is placed over the front opening of the case 43 and the peripheral edge of the lid 47 abuts against the peripheral edge of the front opening, a certain gap is formed from the surface of the substrate 46 (see FIG. 19 described later), and the pressing protrusion 61 abuts against the surface of the substrate 46 when the lid 47 is welded (fused and joined) to the case 43 (see FIG. 20 described later). The reason for giving the pressing protrusion 61 such a height structure will be described in detail later.

[0056] 13 to 20, the installation of the substrate 46 in the case 43 and the attachment of the lid 47 will be described in order according to the manufacturing process.

[0057] As shown in Figures 13 and 14, when the substrate 46 is held horizontally (parallel to the bottom surface of the case 43) and inserted into the case 43 through the front opening, the tips of the support protrusions (press-fit protrusions 51 and loose-fit protrusions 58) of the case 43 are first inserted into the fixing holes 67 of the substrate 46 (see Figure 15).

[0058] Next, when the board 46 is moved toward the bottom surface of the case 43 from this state, the terminals 45 b, 62 provided inside the case 43 are inserted into the through-holes 68 provided in the board 46. At this time, the relative positioning of the board 46 and the case 43 in the horizontal direction is almost completed because the tips of the support protrusions 51, 58 have been inserted into the fixing holes 67 in the step shown in FIG. 15 (the board 46 does not shift horizontally beyond the smaller of the gap between the small-diameter portion 52 at the tip of the press-fit protrusion and the inner circumferential surface of the fixing hole 67 and the gap S between the loose-fit protrusion 58 and the fixing hole 67), and the terminals 45 b, 62 can be smoothly inserted into the through-holes 68 (see FIG. 16). At the same time, press-fitting of the press-fit protrusion 51 (insertion of the press-fit portion 53 into the fixing hole 67) begins.

[0059] Then, as shown in FIG. 17, the substrate 46 is advanced backward (towards the bottom of the case) until the back surface of the substrate 46 abuts against the step portion 57, thereby completing the placement of the substrate 46.

[0060] The electrical connection between the terminals 45b, 62 and the substrate 46 (through-hole 68) may be made by a press-fit connection in which the terminals 45b, 62 are press-fit pins (electrical connection is made by pressing them into the through-hole 68), or by soldering after the substrate 46 is placed.

[0061] After placing the substrate 46 in the case 43, the lid 47 is attached to the case 43. As shown in FIGS. 18 and 19 , the lid 47 is placed over the case 43 to close the front opening, and the peripheral edge of the back surface of the lid is brought into contact with the front edge of the case 43. In this state, infrared light is irradiated onto the contact surface between the two (the front edge of the case and the peripheral edge of the lid) to melt the contact surface between the case 43 and the lid 47, while the lid 47 is pressed toward the bottom surface of the case 43. As the contact surface melts, the lid 47 advances toward the bottom surface of the case 43. However, as shown in FIG. 20 , when the pressing protrusion 61 on the back surface of the lid abuts against the surface (front) of the substrate 46, the lid 47 stops advancing. Then, by completing the welding process in this state, the substrate 46 is firmly supported within the case 43, sandwiched between the step 57 and the pressing protrusion 61. In FIG. 20, the welding surface between the cover 47 and the case 43 is indicated by reference numeral 69.

[0062] As described above, according to this embodiment, the substrate 46 can be installed in the case 43 and the lid 47 can be attached by a relatively simple operation of simply pressing the substrate 46 toward the bottom surface of the case 43 and welding the lid 47. Furthermore, the fusion depth between the case 43 and the lid 47 (the degree to which the case 43 and the lid 47 are fused in the vertical direction (front-to-back direction)) can be set by the height (length in the front-to-back direction) of the pressing protrusion 61. Therefore, according to this embodiment, by appropriately setting the height of the pressing protrusion 61, it is possible to prevent situations in which the airtightness of the case 43 is insufficient due to insufficient fusion depth or, conversely, excessive fusion occurs. This makes it possible to maintain consistent and excellent sealing quality of the case 43 when mass-producing motor-operated valves 11. Furthermore, the joining operation of the lid 47 can be uniformly completed when the pressing protrusion 61 abuts against the surface of the substrate 46, thereby enabling efficient installation of the lid 47.

[0063] Furthermore, Figure 21 shows a structure that prevents incorrect installation of the board 46. As shown in the figure, in this embodiment, notches 81 and 82 of different shapes are formed on the left and right edges of the board 46, respectively, and a protrusion 83 is formed inside the case 43 that fits into one of the notches 81 (in this embodiment, the wider notch on the left side) when the board 46 is correctly positioned. If an attempt is made to position the board 46 upside down, the narrower notch 82 on the right side in Figure 21 will be on the left side, and the protrusion 83 cannot fit into the notch 82, making it immediately clear that the board 46 is upside down. This makes it possible to prevent the board 46 from being mistakenly placed upside down when installing the board.

[0064] Second Embodiment A motor-operated valve according to a second embodiment of the present invention will be described with reference to Figures 22 to 26. Note that, hereinafter, the same components as those in the motor-operated valve 11 of the first embodiment will be assigned the same reference numerals, and redundant explanations will be omitted, with differences being mainly described.

[0065] As shown in Figures 22 to 26, the electric valve 71 of this embodiment adjusts the flow rate of the refrigerant by moving the valve body 17 up and down using an electric motor (stepping motor) 23, similar to the electric valve 11 of the first embodiment, and is provided with a board 46 that controls the electric motor 23, but the board 46 is arranged so that it extends horizontally on the upper surface of the electric motor 23 (stator 25), and a case 43 that houses the board 46 is formed on the upper surface of the electric motor 23.

[0066] In this embodiment, similar to the electric valve 11 of the first embodiment, an outer shell cover 42 (having a coarse dot pattern on the cross section in Figures 7 and 8) that covers the stator 25 and can 22 of the electric motor 23, and a coil cover 41 (having a fine dot pattern on the cross section in Figures 7 and 8) that is arranged inside the outer shell cover 42 and covers the coil 28, but unlike the electric valve 11 of the first embodiment, the connector 44 is not molded integrally with the outer shell cover 42, but is molded integrally with the lid 47 that closes the top opening of the case 43 in a separate process as a lid with connector (lid molding part with connector part) 72.

[0067] Connector-equipped lid 72 is produced through a two-stage molding process. First, in a first process (primary molding), a resin terminal cover (terminal covering molding portion) 63 is molded to cover and support the middle portions of external connection terminals 45, and then in a subsequent second process (secondary molding), connector 44 and lid 47 are molded integrally as connector-equipped lid 72 so that terminal cover 63 is covered and supported between connector 44 and lid 47, in other words, so that one end of terminal cover 63 protrudes into connector interior 44a and the other end of terminal cover 63 protrudes downward from the underside of lid 47.

[0068] After the board 46 is placed inside the case 43a, the connector-equipped lid 72 is welded to the upper edge of the case 43 so as to close the top opening of the case 43. The external connection terminals 45 and the board 46 can be electrically connected by a press-fit connection. Specifically, the base ends (board-side ends) 45a of the external connection terminals 45 are press-fit pins, and when the connector-equipped lid 72 is placed on the top surface of the case 43, the press-fit pins are press-fit into the through holes 68 of the board 46.

[0069] The support structure of the circuit board 46 on the case 43 is the same as that of the first embodiment. That is, the case 43 is provided with press-fit protrusions 51 and loose-fit protrusions 58 as support protrusions, and a step 57 is formed on the bottom surface of each of the support protrusions 51, 58 to support the circuit board 46 from below. The circuit board 46 has fixing holes 67 into which the support protrusions 51, 58 are inserted. Meanwhile, the connector-equipped lid 72 is provided with a pressing protrusion 61 on its back surface (lower surface).

[0070] After installing the substrate 46 in the case 43 while inserting the support protrusions 51, 58 into the fixing holes 67 (see Figures 24 to 25), when the connector-equipped lid 72 is welded to the top surface of the case 43 (see Figure 26), the horizontal movement of the substrate 46 is restricted by the press-fit protrusion 51, and the vertical movement of the substrate 46 is restricted by being clamped between the step portion 57 and the pressing protrusion 61, thereby fixing the substrate 46 in the case 43. [Explanation of symbols]

[0071] A Central axis of the motor-operated valve B Central axis of press-fit projection S: Gap between the outer surface of the loose-fitting protrusion and the inner surface of the pressing protrusion 11,71 Motor-operated valve 12 Valve body 12a Top opening 13 Valve chamber 14 Valve seat 15 Outflow channel 16 Inflow channel 17 Valve body 18 Valve stem 18a Torso 18b Upper small diameter section 19 Connecting members 19a Large diameter hole 19b Small diameter hole 21 Base Plate 22 Can 23 Stepping motor (electric motor) 24 magnet rotor 25 Stator 26 York 27 Bobbin 28 coils 31 Valve stem holder 31a Female thread section (screw feed mechanism) 32 Upper stopper body 33 Support ring 34 Push nut 35 compression coil spring 36 Guide bush 36a Large diameter cylindrical part 36b Small diameter cylindrical part 36c Male thread (screw feed mechanism) 37 Lower stopper body 41 Coil cover 42 Outer shell cover 43 cases 43a Inside the case (internal space of the case) 44 connectors 44a Inside the connector (internal space of the connector) 45 External connection terminal 45a Tip of external connection terminal (end on the connector side) 45b Base end of external connection terminal (end on the board side) 46 PCB 47 Lid 51 Press-fit protrusion (support protrusion) 51a: Protrusion body of press-fit protrusion 52 Small diameter section 53 Press-fit section 54 Tapered surface 55 Convex portion 56 Ridgeline 57 Step part 58 Free fit protrusion (support protrusion) 58a Loose-fitting protrusion body 61 Pressing protrusion 62 terminals 63 Terminal cover 64 Notched recess (positioning recess) 65 holes (positioning recesses) 66 Secondary molding die 67 Fixing hole 68 through holes 69 Welding surface between lid and case 72 Lid with connector 81,82 Notch 83 Protrusion

Claims

1. a valve body having a valve chamber communicating with an inlet passage for introducing a refrigerant and an outlet passage for discharging the refrigerant; a valve element that moves toward and away from the valve seat between a closed state in which the valve element is seated on a valve seat in the valve chamber and an open state in which the valve element is separated from the valve seat, thereby changing the flow rate of the refrigerant; an electric motor that drives the valve body; a control board on which electronic components for controlling the electric motor are mounted; a board accommodating section including a case section that accommodates the control board; an outer shell molding portion that covers a stator of the electric motor; a coil covering molding portion provided inside the outer shell molding portion and covering a coil of the electric motor; An electrically operated valve comprising: The coil covering molding part is provided with a concave-convex part that enables the coil covering molding part to be positioned within the outer shell molding part by positioning the coil covering molding part within a mold that forms the outer shell molding part. A motor-operated valve characterized by:

2. A valve body having a valve chamber communicating with an inlet passage for introducing a refrigerant and an outlet passage for discharging the refrigerant; a valve element that moves toward and away from the valve seat between a closed state in which the valve element is seated on a valve seat in the valve chamber and an open state in which the valve element is separated from the valve seat, thereby changing the flow rate of the refrigerant; an electric motor that drives the valve body; a control board on which electronic components for controlling the electric motor are mounted; a board accommodating section including a case section that accommodates the control board; an outer shell molding portion that covers a stator of the electric motor; a coil covering molding portion provided inside the outer shell molding portion and covering a coil of the electric motor; a connector portion including an external connection terminal that enables electrical connection to the outside; a terminal covering molding portion that covers an intermediate portion of the external connection terminal to support the external connection terminal on the connector portion; An electrically operated valve comprising: The coil covering molding part is provided with a concave-convex part that enables the coil covering molding part to be positioned within the outer shell molding part by being positioned within a mold that integrally molds the outer shell molding part and the connector part, The terminal cover molding portion is provided with a concave-convex portion that enables the terminal cover molding portion to be positioned within the connector portion by being positioned within a mold that integrally molds the outer shell molding portion and the connector portion. A motor-operated valve characterized by:

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