JP7260159B2 - Stator unit, motor-operated valve, and stator unit manufacturing method - Google Patents

Description

The present invention relates to a stator unit and an electrically operated valve using the stator unit.

An automobile air conditioner is generally configured by arranging a compressor, a condenser, an expansion device, an evaporator, etc. in a refrigeration cycle. A refrigerating cycle is provided with various control valves, such as an expansion valve as an expansion device, for controlling the flow of refrigerant. 2. Description of the Related Art With the recent spread of electric vehicles and the like, electrically operated valves having a motor as a drive unit are being widely used.

A motor-operated valve is configured by assembling a body containing a valve portion and a motor unit. The motor unit includes a rotor for driving the valve element in the opening/closing direction of the valve portion, and a stator for rotationally driving the rotor. In such an electric valve, from the viewpoint of corrosion prevention, a technique has been proposed in which the stator is coated with molding resin (for example, Patent Document 1). Hereinafter, the part made of mold resin and integrally molded with the stator is called a "case", and the stator and the case are collectively called a "stator unit".

JP 2018-164398 A

By the way, during the molding process, the mold part inserted into the stator for positioning also serves as a supporting member for the stator. In this case, it is necessary to provide a step or the like in the portion of the die part that supports the stator. When molding is performed using such mold parts, the inner diameter of the case becomes larger than the inner diameter of the stator. As a result, the outer diameter of the case also increases, and there is a risk that the size of the stator as a whole will increase. In addition, by determining the size of the body according to the inner diameter of the case, the electric valve as a whole tends to be large. Such problems can similarly occur in motor operated valves used in various applications, not limited to refrigeration cycles.

One of the objects of the present invention is to easily realize a compact stator unit.

One aspect of the present invention is a stator unit. The stator unit includes a stator around which coils are wound, and a case integrally formed with the stator by molding resin. The case has a plurality of insertion traces for supporting one side surface of the stator during molding, and a plurality of covering portions for sealing the insertion traces from the outside.

According to this aspect, by supporting one side of the stator with a plurality of mold parts, it is not necessary to provide a step for supporting the stator in the mold parts for positioning the stator. As a result, the inner diameter of the case can be reduced. Also, the outer diameter of the case can be reduced, so the stator unit can be made compact.

Another aspect of the invention is a motor driven valve. A motor-operated valve includes a rotor for opening and closing a valve portion, and a stator unit. The stator unit includes a stator around which coils are wound, and a case integrally formed with the stator by molding resin. The case has a plurality of insertion traces for supporting one side surface of the stator during molding, and a plurality of covering portions for sealing the insertion traces from the outside.

According to this aspect, by supporting one side of the stator with a plurality of mold parts, it is not necessary to provide a step for supporting the stator in the mold parts for positioning the stator. As a result, the inner diameter of the stator can be reduced. Moreover, since the stator unit can be made compact, the electric valve can also be made compact.

Yet another aspect of the present invention is a method of manufacturing a stator unit applied to an electrically operated valve. A stator unit manufacturing method includes an assembling process of assembling a stator, and a molding process of setting the stator in a mold and injection-molding a mold resin. The mold has a positioning portion that positions the stator in the chamber of the mold, and a support portion that supports the stator at a position separated from the positioning portion. The molding process includes inserting a positioning portion along the axis of the stator and placing the stator on the support to fix the position of the stator within the chamber.

According to this aspect, the portion of the mold that is inserted into the stator and the portion that supports the stator are made different, thereby eliminating the need to provide a step for supporting the stator in the portion that is inserted into the stator. As a result, the inner diameter of the stator can be reduced. Also, the stator unit can be made compact.

According to the present invention, a compact stator unit can be easily realized.

FIG. 4 is a diagram showing the appearance of the motor-operated valve unit; It is a sectional view showing a motor-operated valve unit. It is a sectional view showing an electric valve. It is a sectional view showing a stator unit. It is a perspective view showing the structure of a stator. It is a figure showing the state which set the stator in the metal mold|die housing. FIG. 4 is a diagram showing the stator and case after molding; FIG. 10 is a diagram showing a state in which heat caulking is applied to the end of the boss portion;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description, for the sake of convenience, the positional relationship of each structure may be expressed based on the illustrated state. Also, in the following embodiments and modifications thereof, substantially the same constituent elements are denoted by the same reference numerals, and description thereof will be omitted as appropriate.

FIG. 1 is a diagram showing the appearance of a motor-operated valve unit U according to an embodiment. Motor-operated valve unit U includes motor-operated valve 1 and piping body 200 . The motor-operated valve 1 is applied to a refrigerating cycle of an automotive air conditioner (not shown). This refrigeration cycle includes a compressor that compresses the circulating refrigerant, a condenser that condenses the compressed refrigerant, an expansion valve that throttles and expands the condensed refrigerant and delivers it in the form of mist, and an evaporator that evaporates the refrigerant in the form of mist. An evaporator or the like is provided to cool the air in the passenger compartment by the latent heat of evaporation. Motor operated valve 1 functions as an expansion valve for the refrigeration cycle.

The electric valve 1 is detachably attached to the piping body 200 via the bracket 220 . The motor-operated valve 1 is constructed by assembling a motor unit 4 to a valve body, which will be described later. Four terminals 58 extend from the side surface of the motor unit 4 . A first passage 202 and a second passage 204 are provided in the piping body 200 . The first passage 202 and the second passage 204 will be described later. A threaded hole 206 is provided on the upper side of the piping body 200 . A bracket 220 (connecting portion) is integrally provided below the motor unit 4 in a manner fixed by a covering portion 106 described later. A screw insertion hole 222 is opened at the end of the bracket 220 . By coaxially arranging the opening end of the screw hole 206 and the screw insertion hole 222 and inserting the male screw member 240, the electric valve 1 and the piping body 200 are assembled.

FIG. 2 is a cross-sectional view showing the motor-operated valve unit U. As shown in FIG.
The electric valve 1 is configured by assembling a motor unit 4 to a valve body 2 . The valve main body 2 has a body 5 that accommodates a valve portion. The body 5 functions as a "valve body". The body 5 is configured by assembling a first body 6 and a second body 8 coaxially.

The first body 6 has a stepped cylindrical shape whose outer diameter gradually decreases downward. A circular hole-shaped concave fitting portion 10 is provided in the lower portion of the first body 6 . The second body 8 has a cylindrical shape with a bottom, and its upper portion is press-fitted into the concave fitting portion 10 . A valve hole 12 is provided so as to axially penetrate the bottom of the second body 8 , and a valve seat 14 is formed at the upper end opening of the valve hole 12 . An inlet port 16 is provided at the side of the second body 8 and an outlet port 18 is provided at the bottom. A valve chamber 20 is formed inside the first body 6 and the second body 8 . The inlet port 16 and the outlet port 18 communicate through the valve chamber 20 .

A first inlet port 208 , a first outlet port 210 , a second inlet port 212 and a second outlet port 214 are provided on the side of the piping body 200 . A pipe extending from the condenser side is connected to the first introduction port 208 , and a pipe leading to the inlet of the evaporator is connected to the first outlet port 210 . A pipe leading to the outlet of the evaporator is connected to the second introduction port 212 , and a pipe extending to the compressor side is connected to the second outlet port 214 . First inlet port 208 communicates with inlet port 16 and first outlet port 210 communicates with outlet port 18 . The first introduction port 208 and the first outlet port 210 communicate with each other through a first passage 202 formed inside the piping body 200 . A second passage 204 connecting the second introduction port 212 and the second outlet port 214 is formed in the piping body 200 . The first passage 202 and the second passage 204 are vertically separated by a partition wall 216 .

Annular sealing members 242 and 244 are interposed between the first body 6 and the piping body 200 and between the second body 8 and the piping body 200, respectively. This configuration prevents fluid from leaking through the clearance between the first body 6 and the piping body 200 and the clearance between the second body 8 and the piping body 200 .

FIG. 3 is a cross-sectional view showing the motor operated valve 1. As shown in FIG.
A guide member 22 is erected at the center of the upper portion of the first body 6 . The guide member 22 is obtained by cutting a tubular member made of a non-magnetic metal into a stepped cylindrical shape, and has a male screw portion 24 formed on the outer peripheral surface of the central portion in the axial direction. The lower end portion of the guide member 22 has a large diameter, and the large diameter portion 26 is press-fitted into the upper center of the first body 6 and fixed coaxially.

An operating rod 28 extending from the rotor 42 of the motor unit 4 is inserted inside the body 5 . An operating rod 28 passes through the valve chamber 20 . The operating rod 28 is obtained by cutting a bar made of non-magnetic metal, and a needle-shaped valve body 30 is integrally provided in the lower part thereof. The valve portion 32 is opened and closed by attaching and detaching the valve body 30 to and from the valve seat 14 from the valve chest 20 side.
The guide member 22 axially supports the actuating rod 28 by its inner peripheral surface, and rotatably and slidably supports the rotating shaft 66 of the rotor 42 by its outer peripheral surface.

An E-ring 34 is fitted to the lower portion of the operating rod 28 inside the valve chamber 20 . A spring receiver 36 is provided above the E-ring 34 . A spring bearing 38 is also provided below the guide member 22, and a spring 40 for urging the valve body 30 in the valve closing direction of the valve portion 32 is coaxial with the valve body 30 between the two spring bearings 36 and 38. inserted. In this embodiment, since the valve element 30 is integrally provided under the operating rod 28, the spring 40 also biases the operating rod 28 in the valve closing direction.

Next, the structure of the motor unit 4 will be explained.
The motor unit 4 is configured as a stepping motor including a rotor 42 and a stator 44 . The motor unit 4 has a cylindrical can 46 with a bottom, a rotor 42 inside the can 46, and a stator 44 outside. The can 46 covers the space in which the valve body 30 and its drive mechanism are arranged, and is inward of the rotor 42. The can 46 is an inner pressure space (internal space) in which the pressure of the refrigerant acts and an outer non-pressure space in which the pressure does not act. (external space).

The stator 44 is configured by assembling a bobbin 50 around which a coil 48 is wound to a yoke 52 having a plurality of pole teeth. The details of the structure of the stator 44 will be described later. The stator 44 is provided integrally with the case 54 of the motor unit 4 . That is, the case 54 is obtained by injection molding of a resin material having corrosion resistance. The stator 44 is covered with molding resin obtained by injection molding (also called “insert molding” or “molding”). The case 54 is made of the mold resin. The case 54 has a cylindrical shape with a bottom. A terminal cover portion 57 is provided on the side surface of the case 54 to protect a terminal 58 for supplying power from an external power source to the coil 48 . Hereinafter, the molded product of the stator 44 and the case 54 will also be referred to as a "stator unit 56".

A plurality of cylindrical bosses 108 protrude from the lower end surface of the case 54 . A substantially hemispherical covering portion 106 is provided at the end of the boss portion 108 . The inner peripheral surface of the boss portion 108 is formed by a mold used for molding (details will be described later). The boss portion 108 is inserted through an insertion hole 224 provided in the bracket 220 . In this embodiment, eight boss portions 108 and eight insertion holes 224 are provided. The covering portion 106 is obtained by thermally crimping the end portion of the boss portion 108 . By inserting the boss portion 108 through the insertion hole 224 and thermally crimping the end portion of the boss portion 108 , the cover portion 106 is formed and the bracket 220 and the case 54 can be fixed. A mold resin injection mark 110 is formed on the upper end surface of the case 54 (details will be described later).

An annular seal member 60 is interposed between the first body 6 and the case 54 . This configuration prevents outside air (moisture, etc.) from entering through the clearance between the first body 6 and the case 54 .

The rotor 42 includes a cylindrical rotor core 62 and magnets 64 provided along the outer circumference of the rotor core 62 . The rotor core 62 is attached to the rotating shaft 66 . The magnet 64 is magnetized with multiple poles in the circumferential direction.

The rotating shaft 66 is a machined product made of a metal material. The rotary shaft 66 is fitted around the guide member 22 with its open end facing downward. A female threaded portion 68 is formed on the inner peripheral surface of the rotating shaft 66 and meshes with the male threaded portion 24 of the guide member 22 . A screw feeding mechanism using these screw portions converts the rotary motion of the rotor 42 into translational motion in the axial direction.

The upper portion of the operating rod 28 has a reduced diameter, and the reduced diameter portion penetrates the bottom of the rotating shaft 66 . An annular stopper 70 is fixed to the tip of the reduced diameter portion. On the other hand, a back spring 76 is interposed between the base end of the diameter-reduced portion and the bottom of the rotary shaft 66 to bias the operating rod 28 downward (in the valve closing direction). With such a configuration, when the valve portion 32 is opened, the operating rod 28 is displaced integrally with the rotor 42 in such a manner that the stopper 70 is engaged with the bottom portion of the rotating shaft 66 . On the other hand, when the valve portion 32 is closed, the reaction force that the valve body 30 receives from the valve seat 14 compresses the back spring 76 . The valve body 30 can be pressed against the valve seat 14 by the elastic reaction force of the back spring 76 at this time, and the seating performance (valve closing performance) of the valve body 30 can be enhanced.

FIG. 4 is a cross-sectional view showing the stator unit 56. As shown in FIG.
Stator 44 includes coil 48 , bobbin 50 and yoke 52 , as described in connection with FIG. 3 . As shown in FIG. 4, the stator unit 56 includes two coaxially assembled stators 44 (an upper stator 44m and a lower stator 44n). The upper stator 44m and the lower stator 44n have the same shape, and are arranged symmetrically with respect to their contact surfaces. The case 54 is formed in such a manner that the mold resin covers the upper stator 44m and the lower stator 44n. The coil 48 of the upper stator 44m is electrically configured as a first-phase coil. On the other hand, the coil 48 of the lower stator 44n is electrically configured as a second phase coil. Rotation control of the stepping motor is performed while sequentially switching between one-phase excitation in which one of the coils is excited and two-phase excitation in which both coils are excited.
The bobbin 50 includes a fitting protruding portion 94 , a thick portion 93 and a thin portion 95 . The details of the shape of the bobbin 50 will be described later.

FIG. 5 is a perspective view showing the structure of the stator 44. FIG.
Stator 44 includes two yokes (first yoke 52a, second yoke 52b) and accommodates bobbin 50 therebetween. In this embodiment, the first yoke 52a and the second yoke 52b have the same shape. Hereinafter, the first yoke 52a and the second yoke 52b will be referred to as "yoke 52" unless otherwise distinguished. Further, when indicating each part of the yoke 52, an identifier a is given to indicate the portion of the first yoke 52a, and an identifier b is given to indicate the portion of the second yoke 52b. is not added.

The yoke 52 is obtained by bending a blank made of metal material. The yoke 52 has a substantially annular base 84 . A plurality of pole teeth 86 are formed on the inner periphery of the base 84 and arranged at equal intervals in the circumferential direction. Each pole tooth 86 is erected by bending the inner end portion of the yoke 52 in the axial direction in a comb-like shape. A part of the outer peripheral portion of the base 84 is a notch portion 85 that is cut in a direction perpendicular to the radial direction. A plurality of walls 88 arranged at equal intervals in the circumferential direction are formed on the outer peripheral portion of the base 84 except for the notch portion 85 . The wall 88 extends in the axial direction and has a substantially rectangular shape. The wall 88 is formed by cutting out the outer end of the yoke 52 in a stepped shape and bending it so as to raise it in the axial direction.

Bobbin 50 includes a tubular core 82 , an annular upper flange 78 and an annular lower flange 80 . A coil 48 is wound around the core portion 82 . The ends of the windings of coil 48 are connected to two terminals 58 extending from the sides of bobbin 50 . The inner peripheral portion of the upper flange 78 is connected to the upper end portion of the core portion 82 , and the inner peripheral portion of the lower flange 80 is connected to the lower end portion thereof. The upper flange 78 faces the base 84a of the first yoke 52a. The lower flange 80 axially faces the base 84b of the second yoke 52b. A fitting protrusion 94 extending radially outward is provided on the outer peripheral portion of the lower flange 80 . The fitting projecting portion 94 includes two thick portions 93 having a large thickness in the axial direction of the bobbin 50 and two thin portions 95 having a small thickness alternately provided in the circumferential direction of the lower flange 80 . . The thick portion 93 is provided with two holes 96 into which the terminals 58 are inserted.

When the first yoke 52 a and the second yoke 52 b are assembled to the bobbin 50 , the pole teeth 86 a and 86 b are positioned inside the bobbin 50 . The total number of bipolar teeth 86a, 86b is equal to the number of magnetic poles of magnet 64 (see FIG. 3). Also, the walls 88a, 88b are located outside the bobbin 50. As shown in FIG. The pole teeth 86a, 86b are assembled alternately in the circumferential direction. The walls 88a and 88b are also assembled alternately in the circumferential direction. An opening 104 is formed by the cutouts 85a, 85b and the walls 88a, 88b. The fitting protrusion 94 is inserted through the opening 104 .

Returning to FIG. 4, assembly of the upper stator 44m and the lower stator 44n will be described.
As described above, the stator 44 has an upper stator 44m and a lower stator 44n. The upper stator 44m and the lower stator 44n are assembled coaxially by fitting the fitting projections 94 of both. That is, the lower end surface of the thin portion 95 of the upper stator 44m contacts the upper end surface of the thick portion 93 of the lower stator 44n, and the lower end surface of the thick portion 93 (see FIG. 5) of the upper stator 44m contacts the lower stator 44n. contact with the upper end surface of the thin portion 95 (see FIG. 5). With such a structure, the fitting protrusions 94 of the upper stator 44m and the lower stator 44n are fitted to each other, and the upper stator 44m and the lower stator 44n are assembled.

As described above, the stator 44 is covered with molding resin. Details of the method (molding process) for covering the stator 44 with the case 54 will be described below.

FIG. 6 is a cross-sectional view showing a mold housing 300 for manufacturing the case 54 (see FIG. 4) by a molding process. FIG. 6 shows a state in which the stator 44 is set inside the mold housing 300. As shown in FIG.
As described with reference to FIG. 3, the case 54 is manufactured by injection-molding the stator 44 with molding resin. In the manufacturing process, this process by molding is called "molding process". A mold housing 300 is used during molding. The mold housing 300 is composed of a first mold 310 , a second mold 320 and a third mold 330 . A chamber is formed by the first mold 310, the second mold 320, and the third mold 330 during molding.

The first mold 310 is used for molding the lower half of the case 54 (see FIG. 4). The first mold 310 has a cylindrical portion 312 inside. The first mold 310 is provided with a plurality of support portions 314 at positions separated from the cylindrical portion 312 . Each of the support portions 314 supports the lower stator 44n from below. The second mold 320 is used for molding the inner peripheral surface of the terminal cover portion 57 (see FIG. 3). A third mold 330 is used to mold the upper half of the case 54 . The third mold 330 is provided with a hole 332 penetrating between the upper surface and the chamber-side surface. Mold resin is introduced into the chamber through the hole 332 .

A method of assembling the stator 44 to the mold housing 300 will be described.
First, the stator 44 is fitted to the cylindrical portion 312 so that the outer peripheral surface of the cylindrical portion 312 and the inner peripheral surface of the stator 44 are brought into contact with each other. Also, the stator 44 is placed on the support portion 314 . After the second mold 320 is placed on the first mold 310, the third mold 330 is placed on the first mold 310 and the second mold 320 so as to cover them. When the stator 44 is assembled to the mold housing 300 , the hole portion 332 and the support portion 314 are arranged on opposite sides of the stator 44 .

After the stator 44 is positioned with respect to the mold housing 300 , mold resin is poured into the chamber defined by the mold housing 300 through the hole 332 . As a result, the stator 44 is covered with the mold resin to form the case 54 (FIG. 4).
The mold resin is introduced from the hole 332 and flows downward inside the chamber. Therefore, the molding resin flows from the upper surface to the lower surface of the stators 44m and 44n. A stator unit 56 (see FIG. 4) is obtained by introducing the mold resin into the chamber.

FIG. 7 is a diagram showing the stator 44 and case 54 after molding. (A) is a longitudinal sectional view, and (B) is a bottom view.
FIG. 8 is a diagram showing a state in which the end portion of the boss portion 108 is thermally crimped. (A) is a longitudinal sectional view and (B) is a bottom view.

As shown in FIG. 7A, the end of the boss portion 108 is open after molding. The inner peripheral surface of this boss portion 108 is formed by a support portion 314 (see FIG. 6). That is, the inner peripheral surface of the boss portion 108 can also be said to be an insertion mark 112 of the support portion 314 (see FIG. 6). Further, the injection marks 110 are formed when the mold resin is introduced from the hole 332 (see FIG. 6). For this reason, in the case 54, an injection mark 110 is formed on one side surface of the stator 44 in the axial direction, and an insertion mark 112 is formed on the opposite side surface. As shown in FIG. 7B, in this embodiment, eight boss portions 108 are provided on the lower end surface of the case 54 in the circumferential direction.

As described with reference to FIG. 3, boss portion 108 is inserted through hole 224 of bracket 220 . As shown in FIG. 8A, the boss portion 108 after molding is inserted into the insertion hole 224 so that the end portion of the boss portion 108 protrudes. Then, the opening end of the boss portion 108 is thermally crimped (welding step). The bracket 220 is fixed to the case 54 by this thermal crimping. The opening of the boss portion 108 is closed by heat crimping. A portion of the boss portion 108 deformed by heat crimping becomes the covering portion 106, and the insertion mark 112 is closed. In this embodiment, as shown in FIG. 8B, all eight boss portions 108 are thermally crimped. Therefore, eight covering portions 106 are also formed.

As described with reference to FIG. 7A, the inner peripheral surface of the boss portion 108 is the insertion mark 112 of the support portion 314 . During molding, the upper end surface of the support portion 314 (see FIG. 6) contacts the lower end surface of the stator 44 . Therefore, after molding, the lower end surface of the stator 44 is exposed at the inner peripheral portion of the boss portion 108 . By heat crimping the open end of the boss portion 108 to form the covering portion 106, the inside of the boss portion 108 can be sealed from the outside, and the lower end surface of the stator 44 can be shielded from the outside atmosphere.

As described above, according to the present embodiment, the lower end surface of the stator 44 is supported by the support portion 314 when the case 54 is manufactured by molding. That is, since it is not necessary to provide a step for supporting the stator 44 in the cylindrical portion 312, the inner diameter of the case 54 can be reduced as a result. As a result, the outer diameter of the stator unit 56, that is, the size of the entire stator unit 56 can be reduced. By reducing the inner diameter of the case 54, the size of the first body 6 can be reduced. Therefore, the size of the electric valve 1 can also be made compact.

According to this embodiment, the supporting portion of the stator 44 is the portion corresponding to the boss portion 108 of the case 54 during molding. This boss portion 108 is a projection necessary when assembling the bracket 220 to the stator unit 56, and is a portion that requires heat crimping. By arranging the abutting portion of the support portion 314 on the stator 44 in this way, the bracket 220 can be fixed by thermal crimping and the insertion mark 112 can be sealed at the same time, and the waterproofness of the stator 44 can be easily improved.

Although the preferred embodiments of the present invention have been described above, it goes without saying that the present invention is not limited to those specific embodiments, and that various modifications are possible within the scope of the technical idea of the present invention. Nor.

In the above embodiment, the stator unit is configured as a part of the motor-operated valve unit, and the fixing target of the stator unit is the pipe body. A bracket was used as a connecting portion between the stator unit and the pipe body. In a modification, the stator unit may be fixed to the motor-operated valve body or the like, and a bracket may be used as the connecting portion between the stator unit and the motor-operated valve body or the like. Alternatively, the motor-operated valve may be fixed to the stator unit. In this case, a flange may be provided at the open end of the can, and this flange may be used as the connecting portion. Alternatively, a flange may be provided on the body of the motor-operated valve, and this flange may be used as the connecting portion.

In the above embodiment, eight support portions are provided and insertion marks are formed for all eight boss portions. In a modification, it is also possible to adopt a mode in which insertion marks are formed in some of the plurality of boss portions. For example, four supporting portions may be provided so that four of the eight boss portions are formed with insertion marks.

In the above embodiment, the opening end of the boss is heat crimped in order to seal the insertion trace. In a modification, heat treatment may be applied to the end portion of the boss portion to weld the inner peripheral surface of the boss portion, or resin may be injected into the inside of the boss portion and solidified to seal the insertion mark from the outside. . Alternatively, the opening of the boss portion may be sealed by press-fitting or fitting a resin material into the opening.

In the above-described embodiment, the portion corresponding to the projection required when assembling the connecting portion to the motor-operated valve is used as the position where the supporting portion is arranged. In a modified example, a portion corresponding to a portion other than the connection portion with the connection portion in the case may be used as the placement portion of the support portion.

In the above embodiment, the case has a cylindrical shape with a bottom. In a modification, the case may be cylindrical, and a separate cover may be provided to cover the open end.

In the above-described embodiment, the insertion marks are provided on the surface of the case opposite to the surface on which the injection marks are formed. In a modification, an insertion mark may be provided on a surface adjacent to the surface on which the injection mark is formed.

In the above embodiment, the stator includes a yoke having pole teeth. In a variant, it may be a stator or the like that includes a laminated core.

In the above embodiment, the electric valve is configured as an expansion valve, but it may be a control valve such as an on-off valve or an electromagnetic valve that does not have an expansion function.

The motor-operated valve of the above embodiment is suitably applied to a refrigeration cycle that uses a CFC substitute (HFC-134a) as a refrigerant, but it can also be applied to a refrigeration cycle that uses a refrigerant with a high operating pressure, such as carbon dioxide. is. In that case, an external heat exchanger such as a gas cooler is arranged in the refrigeration cycle instead of the condenser.

In the above embodiment, an example in which the electric valve is applied to the refrigerating cycle of an automotive air conditioner is shown, but the electric valve is applicable not only to vehicles but also to air conditioners equipped with electric expansion valves. Also, it can be configured as an electrically operated valve that controls the flow of fluid other than refrigerant.

It should be noted that the present invention is not limited to the above-described embodiments and modifications, and can be embodied by modifying constituent elements without departing from the scope of the invention. Various inventions may be formed by appropriately combining a plurality of constituent elements disclosed in the above embodiments and modifications. Also, some constituent elements may be deleted from all the constituent elements shown in the above embodiments and modifications.

Reference Signs List 1 electric valve 2 valve body 4 motor unit 5 body 6 first body 8 second body 10 recessed fitting portion 12 valve hole 14 valve seat 16 inlet port 18 outlet port 20 valve chamber , 22 guide member, 24 male screw portion, 26 large diameter portion, 28 operating rod, 30 valve body, 32 valve portion, 34 E-ring, 36 spring bearing, 38 spring bearing, 40 spring, 42 rotor, 44 stator, 46 can, 48 coil, 50 bobbin, 52 yoke, 54 case, 56 stator unit, 57 terminal cover portion, 58 terminal, 60 sealing member, 62 rotor core, 64 magnet, 66 rotating shaft, 68 female screw portion, 70 stopper, 76 back spring, 78 upper flange, 80 lower flange, 82 core, 84 base, 85 notch, 86 pole tooth, 88 wall, 93 thick portion, 94 fitting protrusion, 95 thin portion, 96 hole, 104 opening, 106 Coating Part 108 Boss Part 110 Injection Mark 112 Insertion Mark 200 Piping Body 202 First Passage 204 Second Passage 206 Screw Hole 208 First Introduction Port 210 First Outlet Port 212 Second Introduction port, 214 second lead-out port, 216 partition wall, 220 bracket, 222 screw insertion hole, 224 insertion hole, 240 male screw member, 242 seal member, 300 mold housing, 310 first mold, 312 cylindrical portion, 314 support portion, 320 second mold, 330 third mold, 332 hole, U electric valve unit.

Claims (6)

a stator wound with a coil;
a case integrally formed with the stator by molding resin;
including
Said case is
Insertion traces of a plurality of mold parts that support one side of the stator during molding;
a plurality of covering portions that seal the insertion mark from the outside;
has
A stator unit according to claim 1, wherein said covering portion is a weld mark due to heat treatment after said molding . 2. The stator according to claim 1 , wherein the covered portion is formed by thermally crimping a connecting portion connecting the stator unit and a fixing target in a peripheral portion of the insertion mark in the mold resin. unit. 3. The stator unit according to claim 1 , wherein the case has a cylindrical shape with a bottom, and the surface opposite to the surface on which the covering portion is provided is closed. 4. The case according to any one of claims 1 to 3, wherein the case has injection traces of the molding resin on one side surface in the axial direction with respect to the stator unit, and has the covering portion on the opposite side surface in the axial direction. stator unit. In a motor-driven valve,
a rotor for opening and closing the valve;
a stator unit including a stator around which a coil is wound and a case integrally formed with the stator by molding resin;
a connecting portion consisting of a bracket or a flange for connecting the stator unit and its fixed object;
with
Said case is
Insertion traces of a plurality of mold parts that support one side of the stator during molding;
a plurality of covering portions that seal the insertion mark from the outside;
has
While the boss portion having the insertion mark protrudes from one side surface of the case,
an insertion hole through which the boss portion is inserted is provided in the connection portion;
The motor -operated valve, wherein the covering portion is a mark formed by closing the open end of the boss portion by thermal crimping . A method for manufacturing a stator unit applied to a motor-operated valve, comprising:
an assembly process for assembling the stator;
a molding step of setting the stator in a mold and injecting mold resin;
with
The mold is
a positioning part that positions the stator in the chamber of the mold;
a support portion that supports the stator at a position separated from the positioning portion;
has
The molding step includes
inserting the positioning portion along the axis of the stator;
placing the stator on the support to fix the position of the stator in the chamber ;
A method of manufacturing a stator unit , further comprising a welding step of forming a covering portion that seals the insertion trace of the support portion from the outside by performing heat treatment after the molding step.

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