JP7116999B2 - electric valve - Google Patents

Description

TECHNICAL FIELD The present invention relates to an electrically operated valve, and more particularly to an electrically operated valve constructed by assembling a motor unit and a body.

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 is constructed by arranging the rotor inside the stator unit. As such an electric valve, there is one in which a stator unit and a body are connected via a connection plate (for example, Patent Document 1). The stator unit is configured by enclosing a stator in a resin main body, and a connector is integrally provided on the side of the main body. A connection plate is welded to the stator unit in advance, and the connection plate is screwed to the body, thereby fixing the stator unit and the body.

Chinese Patent Application Publication No. 107620824

However, such an electrically operated valve requires a specially shaped connection plate having a plurality of holes for welding, which increases the cost. In addition, when a welding process is provided in the mass production of motor-operated valves, it becomes complicated in that the welding conditions must be managed. Such a problem may occur with motor operated valves used in various applications, not limited to the refrigeration cycle of vehicles.

SUMMARY OF THE INVENTION One of the objects of the present invention is to facilitate assembly of a motor-operated valve in which a stator unit is fixed to a body.

One aspect of the present invention is an electrically operated valve. This electric valve is configured by assembling a body having a valve portion and a motor unit. The motor unit includes a stator unit including a stator covered with molding resin, and a rotor arranged inside the stator. The body has a threaded hole into which a screw for fixing the stator unit can be screwed. The stator unit is provided continuously or intermittently on a virtual circle centered on the axis of the rotor and faces the screw hole, and is provided along the insertion hole through which the screw can be inserted, and the opening of the insertion hole, It has a bearing surface that can lock the head of the screw.

According to this aspect, the stator unit and the body can be directly connected by screwing. Since a separate connection plate is not required, the number of parts can be reduced. In addition, welding is not required, and assembly of the stator unit and the body can be easily achieved.

Another aspect of the invention is also a motor operated valve. This electric valve is configured by assembling a body having a valve portion and a motor unit. The motor unit includes a stator unit including a stator and a rotor arranged inside the stator. The body has a threaded hole into which a screw for fixing the stator unit can be screwed. The stator unit continuously extends along a virtual circle centered on the axis of the rotor, faces the screw hole, and is provided along the slit through which the screw is inserted so that the relative position of the screw can be varied, and along the opening of the slit. It has a seat surface on which the head can be locked.

According to this aspect, the position of the slit through which the screw is inserted can be continuously adjusted, and the mounting angle of the stator unit with respect to the body can be arbitrarily set. Therefore, it is possible to easily assemble the stator unit and the body.

According to the present invention, it is possible to easily assemble the stator unit and the body.

1 is a front view showing an electrically operated valve according to a first embodiment; FIG. It is a sectional view showing an electric valve. FIG. 2 is a diagram showing the configuration of a stator and its surroundings; It is a figure showing the fixing structure of a stator unit and a body. FIG. 4 is a diagram showing degrees of freedom in attaching the stator unit to the body; FIG. 10 is a cross-sectional view showing the configuration of a motor-operated valve according to a modification; It is a front view showing the electric valve which concerns on 2nd Embodiment. It is a sectional view showing an electric valve. FIG. 4 is an explanatory diagram showing a mounting structure between a stator unit and a body; FIG. 4 is a diagram showing degrees of freedom in attaching the stator unit to the body; It is a figure showing the principal part of the electrically operated valve which concerns on a modification.

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.

[First Embodiment]
FIG. 1 is a front view showing an electrically operated valve according to the first embodiment. FIG.
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 sends it out 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.

A motor-operated valve 1 is configured by assembling a valve body 2 and a motor unit 3 . The valve main body 2 has a body 5 that accommodates a valve portion. The motor unit 3 includes a stator unit 78 which will be described later. The motor unit 3 closes the upper end opening of the body 5 .

FIG. 2 is a cross-sectional view showing an electrically operated valve.
The body 5 is configured by assembling a first body 6 and a second body 8 in the axial direction. A lower half of the second body 8 is attached to an upper half of the first body 6 . The first body 6 is made of an aluminum alloy, and the second body 8 is made of a copper alloy. In addition, in a modification, the second body 8 may be made of stainless steel (hereinafter referred to as "SUS").

The first body 6 has a prism shape, and is provided with an introduction port 10 at the upper portion of one side surface and an outlet port 12 at the lower portion of the opposite side surface. A valve portion is arranged in a passage that connects the introduction port 10 and the outlet port 12 . Refrigerant from the upstream side (condenser side) is introduced into the body 5 through the introduction port 10 and guided to the valve portion. The refrigerant throttled and expanded by the valve portion is discharged to the downstream side (evaporator side) through the discharge port 12 .

A vertical connecting passage 14 is formed in the center of the first body 6 , the upstream passage 16 communicates with the introduction port 10 and the downstream passage 18 communicates with the outlet port 12 . A stepped circular mounting hole 20 is formed in the first body 6 . The attachment hole 20 gradually increases in diameter upward. The connection passage 14 forms part of the mounting hole 20 . A female thread 22 is formed at a position slightly above the downstream passage 18 in the mounting hole 20 .

The second body 8 has a stepped cylindrical shape whose outer diameter and inner diameter gradually decrease downward, and is assembled to the first body 6 in such a manner that the lower half of the second body 8 is inserted through the mounting hole 20 . ing. The upper half of the second body 8 protrudes above the mounting hole 20 . A male thread 24 that can be screwed with the female thread 22 of the first body 6 is formed on the lower outer peripheral surface of the second body 8 . An annular seal accommodating portion 26 is formed on the outer peripheral surface of the second body 8 slightly above the male thread 24, and a seal ring 28 is fitted thereon. An annular seal accommodating portion 30 is also formed on the outer peripheral surface of the upper portion of the second body 8, and a seal ring 32 is fitted thereon. A flange portion 34 projecting radially outward is provided between the seal accommodating portions 26 and 30 in the second body 8 .

A valve seat forming member 35 is coaxially attached to the lower portion of the second body 8 . The valve seat forming member 35 has a cylindrical shape with a bottom, and its upper portion is coaxially press-fitted into the lower portion of the second body 8 . An annular seal receiving portion 36 is formed on the lower outer peripheral surface of the valve seat forming member 35, and a seal ring 38 is fitted therein. The valve seat forming member 35 is assembled to the first body 6 at the position of the seal ring 38 thereof.

A valve hole 40 is provided so as to axially penetrate the bottom portion of the valve seat forming member 35 , and a valve seat 42 is formed at the open end of the valve hole 40 . A communication hole 44 is provided at a side portion of the valve seat forming member 35 slightly above the seal accommodating portion 36 to allow communication between the inside and the outside. A valve chamber 45 is formed inside the second body 8 and the valve seat forming member 35 . The valve chamber 45 communicates with the upstream passage 16 via the communication hole 44 .

The second body 8 is attached from above the first body 6 so as to be fitted into the attachment hole 20 . At this time, the second body 8 is assembled to the first body 6 while the male thread 24 is screwed into the female thread 22 . Also, the lower end portion of the valve seat forming member 35 is fitted into the mounting hole 20 (connection passage 14). The second body 8 is fastened to the first body 6 by locking the flange portion 34 to the upper surface of the first body 6 . A seal ring 28 is interposed in the fitting portion between the first body 6 and the second body 8 , and a seal ring 38 is interposed between the first body 6 and the valve seat forming member 35 . The former prevents refrigerant from leaking to the outside. Moreover, the latter prevents leakage of the refrigerant through the clearance between the first body 6 and the valve seat forming member 35 (leakage of the refrigerant bypassing the valve portion).

An operating rod 46 extending from the rotor 60 of the motor unit 3 is inserted inside the second body 8 . The operating rod 46 passes through the valve chamber 45 . The operating rod 46 is obtained by cutting a bar made of non-magnetic metal, and a needle-shaped valve body 48 is integrally provided at the lower portion thereof. The valve portion is opened and closed by attaching and detaching the valve element 48 to and from the valve seat 42 from the valve chest 45 side.

A guide member 50 is erected at the center of the upper portion of the second body 8 . The guide member 50 is obtained by cutting a tubular member made of a non-magnetic metal into a stepped cylindrical shape, and has a male thread 52 formed on the outer peripheral surface of the central portion in the axial direction. The lower end portion of the guide member 50 has a large diameter, and the large diameter portion 54 is coaxially fixed to the upper center of the second body 8 . The guide member 50 slidably supports the operating rod 46 in the axial direction by its inner peripheral surface, and slidably supports the rotation shaft 62 of the rotor 60 by its outer peripheral surface.

A spring receiver 49 is provided on the operating rod 46 slightly above the valve body 48 , and a spring receiver 56 is also provided on the bottom of the guide member 50 . A spring 58 (functioning as a "biasing member") is interposed between the spring bearings 49 and 56 to bias the valve body 48 in the valve closing direction.

On the other hand, motor unit 3 is configured as a three-phase stepping motor including rotor 60 and stator 64 . The motor unit 3 has a cylindrical can 66 with a bottom, the rotor 60 is arranged inside the can 66, and the stator 64 is arranged outside. The can 66 is a bottomed cylindrical member that covers the space in which the valve body 48 and its drive mechanism are arranged and that encloses the rotor 60. The can 66 acts as an inner pressure space (internal space) where the pressure of the refrigerant acts. and an outer non-pressure space (external space). The can 66 is made of a non-magnetic metal, and is coaxially fixed to the second body 8 by inserting its lower end opening into the upper end opening of the second body 8 and welding it. A space surrounded by the can 66 and the second body 8 forms the pressure space.

The stator 64 is configured by arranging a plurality of salient poles 72 at regular intervals on the inner peripheral portion of the laminated core 70 . The laminated core 70 is configured by laminating disc-shaped cores in the axial direction. A bobbin 74 around which a coil 73 (electromagnetic coil) is wound is attached to each salient pole 72 . These coils 73 and bobbins 74 constitute a "coil unit 75". In this embodiment, three coil units 75 for supplying three-phase current are provided at intervals of 120 degrees with respect to the central axis of the laminated core 70 .

The stator 64 is provided integrally with a resin case 76 . That is, the case 76 is obtained by injection molding a corrosion-resistant resin material. The stator 64 is covered with molding resin obtained by injection molding (also called “insert molding” or “molding”). Hereinafter, the molded product of the stator 64 and the case 76 will also be referred to as a "stator unit 78". The stator unit 78 has a hollow structure and is assembled to the body 5 while coaxially passing through the can 66 .

A circular boss-shaped fitting portion 130 is projected from the upper surface of the first body 6 . The fitting portion 130 is provided coaxially with the second body 8 and has a plurality of screw holes 132 extending therethrough in the radial direction. On the other hand, a cylindrical fitting portion 140 is provided in the lower portion of the case 76, and an arc-shaped connecting portion 142 is provided concentrically on the outside thereof. The fitting portion 140 is fitted so as to be externally inserted on the upper half portion of the second body 8 . An arcuate slit 144 is provided along the side wall of the connecting portion 142 . The slit 144 functions as an insertion hole for the screw 150 (see FIG. 1). Stator unit 78 and body 5 are fixed by screwing screw 150 into screw hole 132 and fastening. The screw 150 is fastened in a direction perpendicular to the axis of the second body 8 (the axis L of the rotor 60).

The rotor 60 includes a cylindrical rotor core 102 assembled to the rotating shaft 62 and magnets 104 provided along the outer circumference of the rotor core 102 . The rotor core 102 is attached to the rotating shaft 62 . The magnet 104 is magnetized (magnetized) with a plurality of poles in its circumferential direction.

The rotary shaft 62 is a cylindrical shaft with a bottom, and is fitted around the guide member 50 with its open end facing downward. A female thread 108 is formed on the lower inner peripheral surface of the rotary shaft 62 and meshes with the male thread 52 of the guide member 50 . With such a configuration, the rotation of the rotor 60 causes the screw feed mechanism to function, and the rotor 60 moves (elevates) in the axial direction.

The upper portion of the actuating rod 46 has a reduced diameter, and the reduced diameter portion 110 penetrates the bottom portion 112 of the rotating shaft 62 . An annular stopper 114 is fixed to the distal end of the reduced diameter portion 110 . On the other hand, a spring 116 is interposed between the base end of the reduced diameter portion 110 and the bottom portion 112 to bias the operating rod 46 downward (ie, in the valve closing direction). With such a configuration, when the valve is opened, the operating rod 46 is displaced integrally with the rotor 60 in such a manner that the stopper 114 is locked to the bottom portion 112 . On the other hand, when the valve is closed, the spring 116 is compressed by the reaction force that the valve element 48 receives from the valve seat 42 . Due to the elastic deformation of the spring 116 at this time, the valve body 48 can be pressed against the valve seat 42 by its reaction force, and the seating performance (valve closing performance) of the valve body 48 can be enhanced.

The motor unit 3 has a circuit board 118 outside the can 66 . The circuit board 118 is fixed inside the case 76 . In this embodiment, various circuits functioning as a control section and a communication section are mounted on the lower surface of the circuit board 118 . Specifically, a drive circuit for driving the motor, a control circuit (microcomputer) that outputs control signals to the drive circuit, a communication circuit for the control circuit to communicate with an external device, each circuit and the motor (coil) A power supply circuit and the like for supplying power are mounted. The upper end of the case 76 is closed with a lid 77 . A circuit board 118 is arranged in the space below the lid 77 in the case 76 .

A pair of terminals connected to the coil 73 extend from the bobbin 74 and are connected to the circuit board 118 . A power supply terminal, a ground terminal, and a communication terminal (also collectively referred to as “connection terminals 81”) extend from the circuit board 118 and pass through the side wall of the case 76 to be drawn to the outside. A connector portion 79 is provided integrally with the side portion of the case 76 , and connection terminals 81 are arranged inside the connector portion 79 .

FIG. 3 is a diagram showing the configuration of the stator 64 and its surroundings. 2A is a cross-sectional view of the stator unit 78, corresponding to the cross-section taken along line BB in FIG. (B) is a diagram showing only the stator 64 (state before resin molding). For reference, FIG. 3A shows the can 66 and the rotor 60 (see two-dot chain lines).

Since the motor unit 3 is a three-phase motor, the coil units 75 are provided around the axis L of the rotor 60 at regular intervals, as shown in FIG. 3(A). Axis L of rotor 60 coincides with the axis of stator 64 . As shown in FIG. 3B, slots 120a to 120c (collectively referred to as "slots 120" when not distinguished) are formed in the inner peripheral portion of the laminated core 70 at intervals of 120 degrees with respect to the axis L. is provided. In each slot 120, salient poles 122a to 122c (generically referred to as "salient poles 122") projecting radially inward from the center are formed, and are U-phase coil 73a, V-phase coil 73b, and W-phase coil 73c, respectively. (collectively referred to as "coil 73") are assembled. A slit 124 having a U-shaped cross section is also formed between the slots 120 adjacent to each other to optimize the magnetic path.

The magnet 104 faces the salient poles 122a to 122c via the can 66. As shown in FIG. In this embodiment, as shown in FIG. 3A, the magnet 104 is magnetized with 10 poles, but the number of poles can be set as appropriate.

FIG. 4 is a cross-sectional view taken along the line AA in FIG. 1, showing a fixing structure between the stator unit 78 and the body 5. As shown in FIG. (A) shows the state before the screws are attached, and (B) shows the state after the screws are tightened. FIG. 5 is a diagram showing the mounting freedom of the stator unit 78 with respect to the body 5. As shown in FIG. (A) to (C) respectively illustrate mounting modes of the stator unit 78 .

As shown in FIG. 4A, the fitting portion 130 of the body 5 has a cylindrical shape. On the other hand, the fitting portion 140 of the stator unit 78 (case 76) is also cylindrical, and an arc-shaped connecting portion 142 is coaxially provided on the outside thereof. The case 76 and the body 5 are coaxially assembled so that the fitting portion 130 is positioned in the gap between the fitting portion 140 and the connecting portion 142 . A radial contact surface between the body 5 and the case 76 has a curved surface with the axis L as the center. Therefore, when the screw 150 is not tightened, the stator unit 78 can be rotated about the axis L while being attached to the body 5 .

A fitting portion 130 of the body 5 is provided with threaded holes 132 at intervals of 90 degrees around the axis L. As shown in FIG. On the other hand, a connecting portion 142 of the case 76 is provided with a slit 144 along its side wall. The slit 144 is continuously provided on an imaginary circle VC centered on the axis L of the body 5 . In this embodiment, it is provided in an angle range of approximately 180 degrees around the axis L. As shown in FIG. The slit 144 is arranged to face the screw hole 132 in the radial direction of the fitting portion 140 . The periphery of the slit 144 on the outer peripheral surface of the connecting portion 142 forms a bearing surface 145 capable of locking the head of the screw 150 . That is, the seat surface 145 is provided along the opening of the slit 144 .

As shown in FIG. 4B, the stator unit 78 and the body 5 are fixed by screwing the screws 150 into the screw holes 132 and fastening them. In the illustrated example, two screws 150 are used for fixing, but three screws or one screw may be used. Even when the screw 150 is screwed into the screw hole 132 , the mounting angle of the stator unit 78 with respect to the body 5 can be arbitrarily changed as long as it is not tightened (loosened). That is, as shown in FIGS. 5A to 5C, the orientation of the connector portion 79 can be arbitrarily set. The position of the stator unit 78 with respect to the body 5 can be fixed by tightening the screw 150 at the set position.

Returning to FIG. 2 , the electric valve 1 configured as described above functions as an electric expansion valve whose valve opening degree can be adjusted by drive control of the motor unit 3 . That is, based on a command from an external device (not shown), the control circuit sets a control amount (motor drive step number) for realizing the target opening, and generates a drive signal (driving pulse) for realizing this. Output to the drive circuit. The drive circuit supplies a three-phase drive current (drive pulse) to each coil 73 at set timings. Thereby, the rotor 60 rotates with high resolution. At this time, if the valve body 48 is separated from the valve seat 42 and the valve is open, the biasing force of the spring 116 causes the stopper 114 to abut against the rotating shaft 62 , and the operating rod 46 and thus the valve body 48 are integrated with the rotor 60 . Operate.

The rotor 60 moves vertically by a screw feed mechanism between the guide member 50 and the guide member 50 . That is, the valve body 48 translates in the opening/closing direction of the valve portion, and the opening degree of the valve portion is adjusted to the set opening degree. This screw feed mechanism converts the rotational motion of the rotor 60 about the axis into translational motion (straight motion) in the axial direction of the operating rod 46 to drive the valve body 48 in the opening and closing direction of the valve portion.

As described above, according to this embodiment, the stator unit 78 and the body 5 can be directly connected by screwing. Since a separate connection plate is not required, the number of parts can be reduced. In addition, welding is not necessary, and assembly of the stator unit 78 and the body 5 can be easily achieved. Further, when assembling the motor-operated valve 1 , the mounting angle of the case 76 with respect to the body 5 can be arbitrarily set by adjusting the position of the slit 144 through which the screw 150 is inserted. Therefore, the degree of freedom in assembling the stator unit 78 and the body 5 is improved. Even if the orientation of the connector portion 79 differs depending on the mounting specifications of the motor-operated valve 1 on the vehicle, it can be easily dealt with.

[Modification]
FIG. 6 is a cross-sectional view showing the configuration of an electrically operated valve according to a modification, and corresponds to FIG. 4(B).
In the first embodiment, as shown in FIG. 4, the slit 144 is exemplified as the insertion hole for the screw 150 . In this modification, a plurality of insertion holes 160 are provided intermittently (at predetermined intervals) along the side surface of the connecting portion 142 (case 176). The insertion holes 160 are circular holes, and are provided on a virtual circle VC centered on the axis L at intervals of 45 degrees. With such a configuration, the mounting angle of the stator unit 178 with respect to the body 5 can be changed at intervals of 45 degrees.

[Second embodiment]
FIG. 7 is a front view showing an electrically operated valve according to the second embodiment.
The electric valve 201 is configured by assembling a valve body 202 and a motor unit 203 . The valve body 202 has a body 205 that is larger than the body 5 of the first embodiment. A plurality of screw holes 132 are provided in the peripheral portion of the upper surface of the body 205 . On the other hand, the stator unit 278 has a flange portion 242 extending radially outward from the lower end portion of the case 276 . Slits 244 are provided in the flange portion 242 so as to straddle portions facing the plurality of screw holes 132 . Stator unit 278 and body 205 are fixed by screwing screw 150 into screw hole 132 and fastening. Screw 150 is fastened parallel to the axis of body 205 .

FIG. 8 is a cross-sectional view showing the motor operated valve 201. As shown in FIG.
A stator unit 278 is assembled to the body 205 such that the upper half of the second body 8 is inserted through the lower end of the case 276 . The case 276 and the second body 8 are assembled coaxially. When the screw 150 is not tightened, the stator unit 278 can be rotated around the axis L of the rotor 60 while being assembled to the body 5 .

FIG. 9 is an explanatory diagram showing a mounting structure between stator unit 278 and body 205. As shown in FIG. (A) is a cross-sectional view taken along line BB in FIG. 7, and (B) is a plan view of the stator unit. 10A and 10B are diagrams showing the degree of freedom of attachment of the stator unit 278 to the body 205. FIG. (A) to (C) illustrate mounting modes of the stator unit 278, respectively.

As shown in FIG. 9A, the upper surface of the body 205 (first body 206) is provided with screw holes 132 at intervals of 45 degrees on an imaginary circle VC1 centered on the axis L. As shown in FIG. On the other hand, as shown in FIG. 9B, the flange portion 242 of the case 276 is provided with a slit 244 along an imaginary circle VC2 having the axis L as its center. The slit 244 is provided in an angular range of approximately 180 degrees around the axis L in this embodiment. The slits 244 are arranged to face the plurality of screw holes 132 . A periphery of the slit 244 on the upper surface of the flange portion 242 forms a bearing surface 245 capable of locking the head of the screw 150 . That is, the seat surface 245 is provided along the opening of the slit 244 .

The stator unit 278 and the body 205 are fixed by screwing a screw 150 (see FIG. 7) into one of the plurality of screw holes 132 and fastening. In this embodiment, two screws 150 are used for this fastening. Even when the screw 150 is screwed into the screw hole 132, the mounting angle of the stator unit 278 with respect to the body 205 can be changed arbitrarily as long as it is not tightened (loosened). That is, as shown in FIGS. 10A to 10C, the orientation of the connector portion 79 can be set in any direction. The position of the stator unit 278 with respect to the body 205 can be fixed by tightening the screw 150 at the set position.

Also in this embodiment, the stator unit 278 and the body 205 can be directly connected by screwing, and the two can be assembled easily. Further, when assembling the electric valve 201, the mounting angle of the case 276 with respect to the body 205 can be arbitrarily set by adjusting the position of the slit 244 through which the screw 150 is inserted. Therefore, the degree of freedom in assembling the stator unit 278 and the body 205 is improved.

[Modification]
FIG. 11 is a diagram showing the main parts of an electrically operated valve according to a modification, and corresponds to FIG. 9(B).
In the second embodiment, as shown in FIG. 9B, the slit 244 is exemplified as the insertion hole for the screw 150 . In this modification, a plurality of insertion holes 160 are provided intermittently (at predetermined intervals) along the periphery of the flange portion 242 . The insertion holes 160 are provided on a virtual circle VC2 around the axis L at intervals of 45 degrees. With such a configuration, the mounting angle of the stator unit 279 with respect to the body 205 can be changed at intervals of 45 degrees.

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-described embodiment and modified example, as the insertion holes for the screws that fasten the stator unit and the body, slits that are continuous in a range of 180 degrees around the axis and a plurality of intermittently arranged circular holes are exemplified. In a modified example, the setting angle of the slit may be changed as appropriate, such as by setting the setting angle to 45 degrees, 60 degrees, 90 degrees, or the like. Slits and circular holes may be mixed. Moreover, the shape of the insertion hole is not limited to these, and a polygonal shape such as a square hole or a hexagonal hole may be adopted.

In the above-described embodiment, the body and the case are coaxially fitted together, and the contact surfaces of the two are curved around the axis. By making the cross section of the fitting portion concentric, the stator unit can be rotated around the axis while assembled to the body in a state in which the screws are not tightened. In a modification, the cross section of the fitting portion may be polygonal. In this case, although the assembly angle of the stator unit with respect to the body (orientation of the connector portion) can be restricted, assembly of the two can be easily achieved without separately providing a connection plate or the like.

In the above embodiment, the case of the stator unit is made of molded resin, but the case may be made of resin without molding, or may be made of metal.

Although not described in the above embodiment, a washer may be provided when tightening the screw. Also in this case, unlike the connection plate described in Patent Document 1, no special parts are involved, so cost reduction can be realized.

Although not described in the above embodiment, a connection member may be provided between the stator unit and the body, and a slit may be provided in the connection member so that the relative position between the two can be changed arbitrarily. For example, a connection plate that can replace the flange portion 242 in FIG. 9B may be provided. The connection plate may be made of a metal plate, and is provided with arcuate slits 244 . By fixing the connection plate to a case (a case 276 without the flange portion 242), the flange portion 242 can be replaced. With such a configuration, the shape of the case itself can be simplified, and the manufacture thereof becomes easy.

In each embodiment, a PM stepping motor is used as the motor unit, but a hybrid stepping motor may be used. Also, in the above embodiment, the motor unit is a three-phase motor, but other motors such as two-phase, four-phase, and five-phase motors may be used. The number of electromagnetic coils in the stator is not limited to three or six, and may be appropriately set according to the number of phases of the motor.

In each embodiment, an example is shown in which the motor-operated valve is configured as a two-way valve having one outlet port for one inlet port. In a variant, it can be configured as a three-way valve with two outlet ports for one inlet port, or as a four-way valve with two outlet ports for two inlet ports.

The motor-operated valve of each 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 each embodiment, the electric valve is configured as an expansion valve, but it may be configured as an on-off valve or a flow control valve that does not have an expansion function.

In each 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 an electric expansion valve. 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 components may be deleted from all the components shown in the above embodiments and modifications.

Reference Signs List 1 electric valve, 2 valve main body, 3 motor unit, 5 body, 10 introduction port, 12 outlet port, 40 valve hole, 46 operating rod, 48 valve body, 60 rotor, 64 stator, 70 laminated core, 73 coil, 76 case , 78 stator unit, 79 connector portion, 130 fitting portion, 132 screw hole, 140 fitting portion, 142 connection portion, 144 slit, 144 insertion hole, 145 bearing surface, 150 screw, 160 insertion hole, 201 electric valve, 202 Valve body, 203 Motor unit, 205 Body, 242 Flange part, 244 Slit, 245 Seat surface, 276 Case, 278 Stator unit, 279 Stator unit, L axis, VC virtual circle, VC1 virtual circle, VC2 virtual circle.

Claims (2)

A motor-operated valve configured by assembling a body having a valve portion and a motor unit,
The motor unit includes a stator unit including a stator coated with molding resin, and a rotor disposed inside the stator,
the body has a threaded hole into which a screw for fixing the stator unit can be screwed;
The stator unit is
an insertion hole provided continuously or intermittently on a virtual circle centered on the axis of the rotor, facing the screw hole, and through which the screw can be inserted;
a seat surface provided along the opening of the insertion hole and capable of locking the head of the screw;
have death,
wherein the stator unit is rotatable around the axis while assembled to the body when the screws are not tightened;
The insertion hole is formed along the side surface of the stator unit A motor-operated valve characterized by: 2. The motor-operated valve according to claim 1 , wherein said insertion hole is a slit whose relative position is variable when said screw is inserted.

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