JP7846271B2 - Electric valve and refrigeration cycle system including the same - Google Patents

Description

This invention relates to an electrically operated valve and a refrigeration cycle system including the same.

In heat pump type refrigeration cycle systems, electric valves used as electrically operated expansion valves are known, for example, as shown in Figure 1 of Patent Document 1.

The electric valve comprises a stepping motor, a valve housing as the valve body, a valve mechanism, and a sealed case as the housing. The stepping motor includes a rotor shaft, a magnet rotor within the sealed case, and a stator coil positioned on the outer circumference of the sealed case opposite the magnet rotor. The male threaded portion of the rotor shaft is screwed into the female threaded portion of the support member of the valve mechanism, described later. The valve housing has a valve chamber that communicates with the first joint pipe and the second joint pipe via the valve port of the valve seat ring. The valve mechanism includes a support member, a valve holder, and a needle valve. The support member, made of synthetic resin, is fixed to the upper end surface of the valve housing by welding via a stainless steel flange portion, which is an insert-molded fixing bracket. Furthermore, the lower open end surface of the sealed case is welded to the upper end surface of the valve housing at a position separated from the outer circumference of the flange portion by a predetermined gap.

For the rotor shaft and magnet rotor to rotate smoothly due to the operation of the stepping motor, it is necessary that an appropriate gap be formed between the inner surface of the sealed case and the outer surface of the magnet rotor, and that the central axis of the sealed case, welded to the upper end surface of the valve housing, lies on the central axis of the valve housing.

Japanese Patent Publication No. 2018-115743

As disclosed in the aforementioned Patent Document 1, the lower open end face of the sealing case 1051 is welded to the upper end face of the valve housing 1011 at a position separated by a predetermined gap Δg from the outer circumference of the flange portion 1033, which serves as the fixing bracket, as partially enlarged in Figure 8(a) of the attached drawings of this application. Note that in Figure 8(a), the illustration of the bead between the sealing case 1051 and the valve housing 1011 is omitted. The predetermined gap Δg is provided in this way to prevent the inner circumferential surface of the lower end of the sealing case 1051 from riding up onto the formed bead (weld buildup) 1033w when the lower open end face of the sealing case 1051 and the upper end face of the valve housing 1011 are welded, and the outer circumference of the flange portion 1033 and the upper end face of the valve housing 1011 (annular joint portion 1011d) are fillet welded. If the gap Δg described above is not provided between the lower inner surface of the sealing case 1051 and the outer surface of the flange portion 1033, then, as partially enlarged in Figures 9(a) and 9(b), the lower inner surface of the sealing case 1051' will ride up onto the bead (weld build-up portion) 1033w'. As a result, the axis of the sealing case 1051' will be misaligned with the axis of the valve housing 1011', and an axial gap Δg' will be formed between the sealing case 1051' and the valve housing 1011'. Therefore, depending on the size of the gap Δg', there is a risk that the lower open end surface of the sealing case 1051' cannot be welded to the upper end surface of the valve housing 1011'.

When such welding work is performed, the sealed case 1051 and the valve housing 1011 are positioned and held using jigs or other fixtures in the welding machine so that the central axis of the sealed case 1051 and the central axis of the valve housing 1011 are aligned on a common central axis.

However, during the assembly process, if it is necessary to adjust and hold the position of the sealed case 1051 and the valve housing 1011 using jigs or the like in a welding machine so that their central axes are aligned on a common central axis, then managing the assembly accuracy in the assembly process of the electric valve becomes complicated. Therefore, there is a need to be able to align the axes of the sealed case 1051 and the valve housing 1011 with high precision during assembly, and to assemble them using simple welding.

Considering the above problems, the present invention aims to provide an electric valve and a refrigeration cycle system including the same, which have a configuration that allows for high-precision alignment of the axes of the housing case and the valve body during assembly without requiring complicated assembly precision control.

To achieve the above objective, the electric valve according to the present invention includes a valve body housing having a valve chamber that movably houses a valve body unit which includes a valve body that communicates with at least one connection port connected to a fluid pipeline and controls the opening and closing of a valve port of a valve seat provided at the connection port; an electromagnetic actuator including a rotor shaft and a magnetic rotor that operates a drive mechanism which causes the valve body unit to move closer to or further away from the valve port of the valve seat in order to adjust the flow rate of fluid passing between the end of the valve body and the periphery of the valve port of the valve seat; a female thread member which guides the valve body unit and rotatably supports the rotor shaft; and a female thread member which is oriented perpendicular to the central axis of the rotor shaft. The valve comprises a fixing bracket having an outer peripheral edge protruding from the outer circumference, fixed to the female thread member, and welded to the periphery of the opening end of the valve body housing into which the lower part of the female thread member is inserted, thereby fixing the female thread member; and a housing case housing the rotor shaft and magnet rotor of the electromagnetic actuator, the female thread member, and the fixing bracket. The fixing bracket is characterized by having a plurality of guide portions formed on its outer peripheral edge concentric with the central axis of the housing case, each having a contact surface that abuts against the inner circumferential surface of the housing case; and a welded portion formed inward in the direction of the central axis of the fixing bracket from the contact surfaces of the guide portions, and welded to the upper surface of the opening end of the valve body housing.

The contact surface of the guide section is formed to lie on the circumference of a common virtual circle centered on the central axis of the rotor shaft. The diameter of this virtual circle may be set to be larger than the outer diameter of the magnet rotor and smaller than the inner diameter of the inner surface of the housing case.

The contact surface of the guide portion may have at least one intersection point where the virtual circle intersects with a line (N = an integer of 3 or more) that divides the circumference of the central axis of the fixing bracket into N equal parts at equal angles.

At least one of the contact surfaces of the multiple guide portions in the fixing bracket may be an arc-shaped surface extending along the inner circumferential surface of the housing case. The welded portion may be fixed to the upper surface of the opening end of the valve body housing by multiple spot welds, multiple spaced-apart fillet welds, or continuous fillet welds.

Furthermore, the electric valve according to the present invention includes a valve body housing having a valve chamber that movably houses a valve body unit which includes a valve body that communicates with at least one connection port connected to a fluid pipeline and controls the opening and closing of a valve port of a valve seat provided at the connection port; an electromagnetic actuator including a rotor shaft and a magnetic rotor that operates a drive mechanism that causes the valve body unit to perform an operation that controls the valve body to move closer to or further away from the valve port of the valve seat in order to adjust the flow rate of fluid passing between the end of the valve body and the periphery of the valve port of the valve seat; a female thread member that guides the valve body unit and rotatably supports the rotor shaft; and an outer peripheral edge having a portion that protrudes from the outer circumference of the female thread member in a direction perpendicular to the central axis of the rotor shaft and fixed to the female thread member. The electromagnetic actuator comprises a stepped fixing bracket that secures the female thread member by being attached and welded to the upper surface of the opening end of the valve body housing into which the lower part of the female thread member is inserted, a rotor shaft and a magnet rotor of an electromagnetic actuator, a female thread member, and a housing case that houses the fixing bracket, wherein the stepped fixing bracket is formed concentrically with the central axis of the housing case and has a contact surface that contacts the inner circumferential surface of the housing case, and a welded portion formed integrally with the guide portion at a position below the guide portion facing the portion enclosed by the inner circumferential surface of the housing case and the upper surface of the opening end of the valve body housing, and is welded to the upper surface of the opening end of the valve body housing which is closer to the central axis of the rotor shaft than the contact surface of the guide portion. The contact surface of the guide portion is formed to lie on the circumference of a common virtual circle centered on the central axis of the rotor shaft, and the diameter of the virtual circle may be set to be larger than the outer diameter of the magnet rotor and smaller than the inner diameter of the inner circumferential surface of the housing case. When a mounting bracket with a stepped edge has multiple guide sections, at least the contact surface of each guide section may have an intersection point where a line (N = an integer of 3 or more) that divides the circumference of the mounting bracket's central axis into N equal parts at equal angles intersects with a virtual circle.

Furthermore, the refrigeration cycle system according to the present invention comprises an evaporator, a compressor, and a condenser, and is characterized in that the aforementioned electric valve is provided in the piping located between the outlet of the condenser and the inlet of the evaporator.

According to the electric valve and refrigeration cycle system including the present invention, the fixing bracket has a plurality of guide portions formed on the outer peripheral edge concentric with the central axis of the housing case, each having a contact surface that abuts against the inner peripheral surface of the housing case, and a welded portion formed inward in the direction of the central axis of the fixing bracket from the contact surfaces of the guide portions between the guide portions, which is welded and fixed to the peripheral edge of the opening end of the valve body housing. Therefore, the housing case and the valve body housing can be assembled with high precision, without requiring complicated assembly accuracy control.

This is a longitudinal cross-sectional view showing the schematic configuration of a first embodiment of the electric valve according to the present invention. Figure 2(a) is a cross-sectional view along the line IIA-IIA shown in Figure 1, illustrating the shape of the fixing bracket; Figure 2(b) is a magnified view of the IIB portion of Figure 2(a); and Figure 2(c) is a diagram illustrating the guide portion of the fixing bracket shown in Figure 2(a). Figure 3(a) shows a second embodiment of the fixing bracket, Figure 3(b) shows a third embodiment of the fixing bracket, and Figure 3(c) shows a fourth embodiment of the fixing bracket. This is a longitudinal cross-sectional view showing the schematic configuration of a second embodiment of the electric valve according to the present invention. This is an enlarged cross-sectional view showing a magnified view of the V portion shown in Figure 4. This figure shows an example of the configuration of a refrigeration cycle system using an example of an electric valve according to the present invention. This figure shows a modified example of a fixing bracket used in an example of an electric valve according to the present invention. Figure 8(a) is a partially enlarged cross-sectional view showing the joint structure of the sealed case, valve body, and fixing bracket of an electric valve as described in prior art documents, and Figure 8(b) is a partially cross-sectional view of the sealed case, valve body, and fixing bracket shown in Figure 8(a). Figure 9(a) is a partially enlarged cross-sectional view showing another example of the joint structure of the sealed case, valve body, and fixing fittings of an electric valve in prior art literature, and Figure 9(b) is an enlarged cross-sectional view showing the IXB portion shown in Figure 9(a).

Figure 1 schematically shows the configuration of a first embodiment of the electric valve according to the present invention, along with the piping.

The concept of "up and down" in the following explanation corresponds, for example, to "up and down" in Figure 1, and indicates the relative positional relationship of each component, not its absolute positional relationship.

The electric valve 100 as the first embodiment, and the electric valve 200 as the second embodiment (see Figure 4), which will be described later, are, for example, positioned as an expansion valve 311 in the piping of the refrigeration cycle system 300 between the outlet of the outdoor heat exchanger 312 (first port 312a) and the inlet of the indoor heat exchanger 315 (first port 315a) during cooling operation, as described later.

During cooling operation, the expansion valve 311 is connected to the primary side piping Du1 by a connecting pipe (second joint 12), which will be described later, and connected to the secondary side piping Du2 by a connecting pipe (first joint 11). The primary side piping Du1 connects the outlet (first port 312a) of the outdoor heat exchanger 312 to the expansion valve 311, and the secondary side piping Du2 connects the inlet (first port 315a) of the indoor heat exchanger 315 to the expansion valve 311. Between the outlet (second port 315b) of the indoor heat exchanger 315 and the inlet (second port 312b) of the outdoor heat exchanger 312, there is a pipe Du3 connected to the outlet of the indoor heat exchanger 315, a flow path switching valve 313, and a pipe Du6 connected to the inlet of the outdoor heat exchanger 312. Furthermore, the compressor 314 is connected to the flow path switching valve 313 by pipes Du4 and Du5. The other end of pipe Du3 is connected to port 313d of the flow path switching valve 313. The other end of pipe Du6 is connected to port 313b of the flow path switching valve 313. One end of pipe Du4 is connected to port 313c of the flow path switching valve 313, and the other end of pipe Du4 is connected to the discharge port of the compressor 314. One end of pipe Du5 is connected to port 313a of the flow path switching valve 313, and the other end of pipe Du5 is connected to the intake port of the compressor 314. During cooling operation, ports 313a and 313d are in communication, and ports 313b and 313c are in communication. As a result, during cooling operation, the refrigerant in the refrigeration cycle system circulates, for example, along the direction indicated by the dashed arrow in Figure 6, with the outdoor heat exchanger 312 functioning as a condenser and the indoor heat exchanger 315 functioning as an evaporator. While the description above describes an expansion valve 311 connected to the primary side piping Du1 via the second joint 12 and to the secondary side piping Du2 via the first joint 11 during cooling operation, this is not the only possible configuration. For example, during cooling operation, the expansion valve 311 may be connected to the primary side piping Du1 via the first joint 11 and to the secondary side piping Du2 via the second joint 12.

On the other hand, during heating operation, the flow path switching valve 313 is switched so that ports 313a and 313b of the flow path switching valve 314 are in communication, and ports 313c and 313d are in communication. As a result, during heating operation, the refrigerant in the refrigeration cycle system circulates, for example, along the direction indicated by the solid arrow in Figure 6, with the indoor heat exchanger 315 functioning as a condenser and the outdoor heat exchanger 312 functioning as an evaporator. The compressor 314 and expansion valve 311 are driven and controlled by a control unit (not shown), and the flow path switching valve 313 is switched.

As shown in Figure 1, the electric valve 100 comprises a valve drive unit disposed within a cylindrical housing case 151, which forms part of the exterior 150 described later, and which drives the valve body unit described later to move up and down; a valve body portion 110 connected to the lower end of the housing case 151 and having a valve seat 112 with a valve port 112a that is opened and closed by the tip of a needle 121 which serves as the valve body; and a valve body unit disposed within the valve body portion 110 and including a needle 121 that opens and closes the valve port 112a of the valve seat 112.

The valve drive unit primarily comprises a rotor shaft 131 for raising and lowering the valve body unit (described later), a female threaded member 132 having a female thread formed on a concentric female threaded portion 132b that fits concentrically with the male threaded portion 131a of the rotor shaft 131, and fixed to the valve body housing 111 as a guide support portion that guides the valve body unit so that it can rise and lower, a magnet rotor 141 fixed concentrically to the guide shaft portion of the rotor shaft 131, rotatably supported and magnetized, and a stator coil (not shown) arranged on the outer circumference of the housing case 151 for rotating the magnet rotor 141. The magnet rotor 141 and the stator coil constitute part of a stepping motor, which is an electromagnetic actuator.

The rotor shaft 131 and the female threaded member 132 form a part of the rotor shaft rotation section 130, which will be described later. Furthermore, the magnet rotor 141 and the stator coil constitute a part of the rotor shaft drive section 140, which will also be described later.

The valve body housing 111 of the valve body portion 110 is formed by processing a metal material such as a stainless steel plate into a cylindrical shape by press working or the like. The valve body housing 111 has a valve chamber 111A that houses the lower end (protruding portion 132B) of the female thread member 132, the other end of the needle 121 which is supported concentrically with the rotor shaft 131 described later, and a cylindrical needle case 125. The other end of the needle 121 protrudes into the valve chamber 111A toward the valve port 112a. Furthermore, the valve chamber 111A has a first port 111b, to which one end of the first joint 11 serving as a first passage is connected, on an axis substantially perpendicular to the central axis of the needle 121, and a valve seat 112 having a valve port 112a adjacent to the second port 111c, to which one end of the second joint 12 serving as a second passage is connected, on an axis common to the central axis of the needle 121.

The upper edge of the circular opening end at the top of the valve body housing 111 has a ring-shaped joint portion 111d formed on the periphery of the opening end, which is joined to the lower end of the housing case 151 (described later).

The first joint 11 and the second joint 12 are both made of copper or stainless steel and are fixed to the valve body housing 111 by brazing or welding, but are not limited to these. Furthermore, in this embodiment, the electric valve is described as having the first port 111b as the inlet side and the second port 111c as the outlet side through which the refrigerant flows, but is not limited to this. The electric valve 100 in this embodiment is a bidirectional electric valve that can also be used with the first port 111b as the outlet side and the second port 111c as the inlet side.

The valve seat 112 is formed from a metal material such as stainless steel or a copper alloy, and is fixed around the second port 111c to which the second joint 12 of the valve body housing 111 is connected by welding or brazing. The needle 121, along with the needle case 125, is positioned to be adjacent to or separated from the valve port 112a, thereby controlling the flow rate of refrigerant passing through the valve port 112a. Here, the valve seat 112 is described as a separate component from the valve body housing 111, but it may also be molded integrally with the valve body housing 111.

The valve body unit 120 mainly comprises a needle 121 that opens and closes the valve port 112a of the valve seat 112, a cylindrical resin spring retainer 123 that engages the flange portion 131b of the rotor shaft 131 with the inner periphery of the open end 125a of the needle case 125 in cooperation with a resin washer 124, a valve spring 122 positioned between the spring engagement portion 123a of the spring retainer 123 and the annular flat portion for spring retention at one end of the needle 121, biasing both in a direction away from each other, and a cylindrical needle case 125 that houses the spring retainer 123, the valve spring 122, and one end of the needle 121.

The needle 121 is made of a metal material such as stainless steel. The needle 121 is moved up and down along the central axis CL by a rotor shaft 131 (described later). This controls the flow rate of the refrigerant passing through the valve port 112a. The side of the needle 121 closest to the valve port 112a has a gently protruding shape in the center. This protruding shape is designed so that the effective opening area increases or decreases depending on the position of the needle 121 relative to the valve port 112a, as described above.

The valve spring 122, positioned inside the roughly cylindrical needle case 125, is compressed and positioned between the needle 121 and the spring engagement portion 123a of the spring retainer 123 (described later). The valve spring 122 prevents the screw thrust from the rotor shaft 131 (described later) from directly applying to the needle 121 and valve port 112a, thereby increasing the durability of the electric valve 100.

The spring retainer 123 is formed in a substantially cylindrical shape, for example, from resin. The spring retainer 123 is located inside the needle case 125, between the flange portion 131b of the rotor shaft 131 (described later) and the needle 121, and is positioned inside the valve spring 122 along the central axis CL. A disc-shaped spring engagement portion 123a, projecting outward in the radial direction, is formed at the end of the spring retainer 123 that contacts the rotor shaft 131. By positioning the spring retainer 123 inside the valve spring 122 and along the central axis CL, the concentricity between the valve spring 122 and the spring retainer 123 is enhanced, improving the operability of the valve body unit 120.

The washer 124 is formed in an annular shape, for example, from a highly slippery resin. The washer 124 is positioned between the flange portion 131b of the rotor shaft 131 (described later) and the open end portion 125a of the needle case 125 (also described later). By providing the washer 124, the direct transmission of the rotor shaft 131's rotation to the needle 121 can be suppressed. This suppresses the rotation of the needle 121, thereby preventing wear between the needle 121 and the valve port 112a of the valve seat 112.

The needle case 125 is formed into a substantially cylindrical shape by pressing or other means using a metal material such as stainless steel. An open end 125a is formed at the end of the needle case 125 facing the rotor shaft 131. The needle case 125 has the function of transmitting the screw driving force of the rotor shaft 131, etc., to the needle 121. The open end 125a of the needle case 125 is positioned to engage with the flange portion 131b of the rotor shaft 131, which is opposite to it. The needle 121 is fixed to the end of the needle case 125 opposite to the open end 125a by welding or other means.

The rotor shaft drive unit 140 comprises a magnetic rotor 141, a rotor fixing member 142, a rotation stopper spring 143, and a movable stopper member 144.

The magnet rotor 141 is housed in a rotor chamber 141A inside the housing case 151 (described later) and is composed of multi-pole permanent magnets formed from ferrite sintered material or the like, with alternating north and south poles. In this embodiment, the magnet rotor 141 is arranged on the outer circumference of the housing case 151 (described later) and, together with a stator coil consisting of a yoke, bobbin, and coil (not shown), constitutes a stepping motor. While a stepping motor is used here, the invention is not limited to this, and similar effects can be obtained by using other electric motors capable of rotating the magnet rotor 141.

The magnetic rotor 141 is supported on the rotor shaft 131 via a rotor fixing member 142. The rotor fixing member 142, which has a hole into which the rotor shaft 131 is inserted, is positioned around the central axis of the rotor shaft 131. The rotor fixing member 142 is press-fitted into the mounting hole of the magnetic rotor 141.

The rotation stopper spring 143 has a coil spring shape and is wound around the cylindrical portion 152b of the rotor support member 152, which will be described later. The upper and lower ends of the rotation stopper spring 143 are locked to the cylindrical portion 152b, respectively.

The movable stopper member 144 has a coil spring shape with approximately one turn and is rotatably positioned around the cylindrical portion 152b of the rotor support member 152. One end of the movable stopper member 144 engages with an engaging projection 141b integrally formed on a predetermined pole of the multi-pole magnet rotor 141, and the other end is screwed onto the rotation stopper spring 143. The movable stopper member 144 moves up and down while rotating around the cylindrical portion 152b in accordance with the rotation of the magnet rotor 141. With this configuration, the rotation stopper spring 143 is positioned without play with respect to the central axis CL of the electric valve 100.

The exterior section 150 comprises a housing case 151, a rotor support member 152, and a cylindrical member 153.

The housing case 151 is formed from a non-magnetic metal material, such as stainless steel sheet, by press working or other methods to create a cup shape. The housing case 151 has approximately the same outer diameter as the valve body housing 111. The circular lower end of the housing case 151 is fixed to the circular upper end of the valve body housing 111 by butt welding around the entire circumference, using methods such as TIG welding, plasma welding, laser welding, or resistance welding. This creates a sealed environment inside the housing case 151. Furthermore, the housing case 151 has dimples 151a formed therein for engaging with the engagement recesses 152c formed in the cup-shaped portion 152a of the rotor support member 152, which will be described later.

The rotor support member 152 is formed from a material such as stainless steel sheet by press working or the like. The rotor support member 152 consists of a cup-shaped portion 152a that contacts and is fixed to the housing case 151, and a cylindrical portion 152b extending downward from the center of the cup-shaped portion 152a. An engagement recess 152c is formed in the cup-shaped portion 152a. The engagement of this engagement recess 152c with the dimples 151a of the housing case 151 fixes the rotor support member 152 to a predetermined mounting position on the housing case 151.

The cylindrical member 153 is made of a highly lubricating material, either metal or synthetic resin. The cylindrical member 153 is positioned inside the cylindrical portion 152b of the rotor support member 152 and rotatably holds the upper end (guide shaft portion) of the rotor shaft 131.

The rotor shaft rotating section 130 comprises a rotor shaft 131, a female threaded member 132, and a fixing bracket 133.

The rotor shaft 131 is formed, for example, from a metal material, is generally cylindrical, and extends vertically along the central axis CL of the electric valve 100. The magnet rotor 141, which is rotated by an electric motor such as a stepping motor (described later), is fixed to the rotor shaft 131 around its axis via a rotor fixing member 142 (described later). As a result, the rotor shaft 131 rotates around the central axis CL together with the magnet rotor 141.

A male threaded portion 131a is formed on the part of the rotor shaft 131 closer to the needle 121 than the rotor fixing member 142. The male threaded portion 131a is screwed into the female threaded portion 132b of the female threaded member 132, which will be described later. Furthermore, a flanged portion 131b, projecting in a disc shape in the outer diameter direction, is formed at the end of the rotor shaft 131 closer to the needle 121 than the male threaded portion 131a. The flanged portion 131b is positioned at a distance from the inner circumferential surface of the opening end 125a of the needle case 125. The diameter of the flanged portion 131b is larger than the diameter of the hole in the opening end 125a, thus preventing it from coming loose.

The female threaded member 132 is formed, for example, from resin in a generally cylindrical shape. A female threaded portion 132b is formed on the upper part of the female threaded member 132, which fits onto the male threaded portion 131a of the rotor shaft 131. The female threaded portion 132b is formed concentrically with the central axis CL of the electric valve 100. The female threaded member 132, through its screw connection with the rotor shaft 131, constitutes part of a screw-feed mechanism that converts the rotational motion of the magnet rotor 141 into linear motion in the direction of the central axis CL of the rotor shaft 131.

A guide chamber 132A is formed in the female thread member 132 below the female thread portion 132b, which slidably accommodates the needle case 125 along with the needle 121. The inner circumferential surface of the female thread member 132 forming the guide chamber 132A serves as a guide surface that movably guides the outer circumferential surface of the cylindrical needle case 125. In addition, a pressure equalization hole 132c that penetrates to the outside is provided in a part of the inner circumferential surface forming the guide chamber 132A. This allows the guide chamber 132A and the rotor chamber 141A to communicate, facilitating the movement of the rotor shaft 131 and the needle case 125. Furthermore, a protruding portion 132B is formed at the end of the female thread member 132 below the portion in which the pressure equalization hole 132c is formed, which is inserted into the open end of the valve body housing 111. A fixing bracket 133 is fixed to the protruding portion 132B by insert molding. In this configuration, the fixing bracket 133 is fixed concentrically with the central axis of the female threaded member 132.

The fixing bracket 133 is, for example, a metal disc-shaped member as shown in Figure 2(a). The arcuate or inclined surface of the recess 133b on the outer circumference of the fixing bracket 133 (described later) is fixed to the annular joint 111d of the valve body housing 111 by welding or the like. As a result, the female thread member 132 is fixed to the valve body housing 111 via the fixing bracket 133. In this case, the female thread member 132 is fixed concentrically with the central axis of the valve body housing 111.

The electric valve 100 of the first embodiment of the present invention, as described above, is equipped with a structure that automatically maintains coaxiality between the housing case 151 and the female threaded member 132 by using the simple-shaped fixing bracket 133 described above, in order to solve the problems of the conventional design. The structure will be described below with reference to Figures 2(a) and 2(b).

Figure 2(a) is a cross-sectional view along the line IIA-IIA shown in Figure 1, illustrating the shape of the fixing bracket 133. Figure 2(b) is a magnified view of the IIB portion of Figure 2(a). Figure 2(c) is a diagram illustrating the guide portion 133c (hereinafter also referred to as the protruding portion 133a) of the fixing bracket 133 shown in Figure 2(a).

As shown in Figures 2(a) and 2(b), the fixing bracket 133 as the first embodiment is, for example, a metal member with a roughly disc shape, and four protrusions 133a are provided along the outer circumference of the disc shape. Each protrusion 133a has a contact surface that projects radially so as to abut against the inner circumferential surface of the housing case 151. The shape of the four protrusions 133a is generally formed in an arc shape so that the tip abuts against the inner circumferential surface 151b of the cup-shaped housing case 151. Note that the contact surfaces are not limited to surface contact only; for example, a portion of the contact surface may be configured to be in line contact or point contact.

The four protrusions 133a are formed along the circumferential direction of the fixing bracket 133 at equal angle (90°) intervals. Each protrusion 133a also has the same width W along the circumferential direction. Four recesses 133b are formed between the consecutive protrusions 133a. Each recess 133b consists of an arcuate surface extending circumferentially from the fixing bracket 133 and inclined surfaces extending from both ends of the arcuate surface to the contact surface of the guide portion 133c. The radius of curvature of the outer surface forming the arcuate portion of the recess 133b is set to be smaller than the radius of curvature of the contact surface forming the protrusions 133a.

In this context, the recess 133b is provided on the outer circumference of the multiple protrusions 133a, excluding the protrusions 133a themselves.

In this case, the recess 133b is formed from an arcuate surface portion extending in the circumferential direction of the fixing bracket 133 and slanted surfaces connected to both ends of the arcuate surface portion and reaching the contact surface of the guide portion 133c. In the recess 133b, for example, if the entire arcuate surface portion is fillet-welded and the slanted surfaces are not welded, the welded arcuate surface portion will form the welded portion 133d. Also, for example, if the arcuate surface portion is welded at predetermined intervals by multiple spot welds and the slanted surfaces are not welded, each spot-welded portion will form the welded portion 133d. Furthermore, if only the two aforementioned slanted surfaces are spot-welded or fillet-welded and the arcuate surface portion is not welded, the spot-welded or fillet-welded portions will form the welded portion 133d. Unwelded arcuate surface portions or slanted surfaces, in other words, arcuate surface portions or slanted surfaces that do not need to be welded, may become welded areas, as shown in Figure 2(b).

In this example, all four contact surfaces of the four protrusions 133a are in contact with the inner circumferential surface 151b of the housing case 151. However, this is not necessarily required; for example, all four contact surfaces of the four protrusions 133a (guide portions 133c) do not need to be in contact with the inner circumferential surface 151b of the housing case 151.

The guide portion 133c (protrusion 133a) will be described in more detail with reference to Figures 2(a) and 2(c). The contact surface of each guide portion 133c is formed to lie on the circumference of a common virtual circle CI centered on the central axis CL of the rotor shaft 131. The radius of the virtual circle CI is set, for example, to the length from the central axis CL of the fixing bracket 133, which is concentric with the rotor shaft 131, to the part furthest from it. As a result, during assembly, the fixing bracket 133 is fitted into the inner circumferential surface 151b of the housing case 151. The guide portion 133c only needs to maintain coaxiality (concentricity, degree of coaxiality) between the housing case 151 and the female screw member 132 to the extent that interference between the inner circumferential surface 151b of the housing case 151 and the rotating magnet rotor 141 is prevented. Therefore, the diameter of the virtual circle CI on the contact surface of the guide portion 133c is set to be larger than the outer diameter of the magnet rotor 141 and smaller than the inner diameter of the inner circumferential surface 151b of the housing case 151 (outer diameter of magnet rotor 141 < diameter of virtual circle CI < inner diameter of housing case 151). Furthermore, as shown in Figure 2(c), it is desirable that the contact surface of the guide portion 133c that contacts the inner circumferential surface 151b of the housing case 151 has an intersection point where the lines dividing the circumference of the central axis CL of the fixing bracket 133 into four equal angles intersect with the virtual circle CI. While four equal divisions are used here, the coaxiality described above can be maintained by dividing it into N equal divisions (where N is an integer of 3 or more).

When the arcuate or inclined surfaces of the four recesses 133b are welded to the joint 111d of the valve body housing 111, the welding is sufficient if it is done at the welded portion 133d, which is located in a part other than the guide portion 133c described above. As described above, the recess 133b is formed from an arcuate surface extending in the circumferential direction of the fixing bracket 133 and inclined surfaces that are connected to both ends of the arcuate surface and reach the contact surface of the guide portion 133c. For example, as shown in Figure 2(b), the welded arcuate or inclined surface is the welded portion 133d in the area including not only the arcuate surface but also the inclined surface in Figure 2(a), which is the part closest to the central axis CL forming the recess 133b. As a result, the bead formed on the welded portion 133d is not outside the virtual circle CI, but is formed in the area inside the virtual circle CI, so there is no risk of the bead interfering with the inner circumferential surface 151b of the housing case 151.

Furthermore, in Figure 2(a), the welded portion 133d cannot be positioned inside the inner diameter of the annular joint portion 111d of the valve body housing 111, as indicated by the dashed line. This is because the fixing bracket 133 and the valve body housing 111 cannot come into contact, making welding and fixing impossible.

In this configuration, when assembling the electric valve 100 described above, first, the rotor shaft 131 and the needle case 125 to which the needle 121 is fixed are attached to the female thread member 132. Next, the protruding portion 132B of the female thread member 132 is inserted into the open end of the valve body housing 111, and the fixing bracket 133 is placed on the periphery of the open end of the valve body housing 111, to which the valve seat 112 etc. are pre-attached. Subsequently, for example, the arcuate surface portion of the recess 133b of the fixing bracket 133 and the periphery of the open end of the valve body housing 111 are fixed by fillet welding using a first welding machine (not shown). As a result, a first bead is formed between the welded arcuate surface portion 133d and the joint portion 111d of the valve body housing 111.

Furthermore, the radial gap between the protruding portion 132B of the female threaded member 132 and the open end of the valve body housing 111 may be set to, for example, a clearance fit or an interference fit.

Next, after the magnet rotor 141 is attached to the rotor shaft 131, the valve body housing 111 is removed from the first welding machine, and the assembled valve body housing 111 is transferred to the support stand (not shown) of the second welding machine. Then, the lower end of the housing case 151 is placed without gaps on the periphery of the opening end of the valve body housing 111, so that the inner circumferential surface 151b of the housing case 151, to which the rotor support member 152 etc. are attached, abuts against the contact surface of the guide portion 133c of the fixing bracket 133 at the periphery of the opening end of the valve body housing 111, to which the welded portion 133d of the fixing bracket 133 is fixed. This automatically aligns the axis of the housing case 151 with the axis of the rotor shaft 131 and the female thread member 132.

Then, on the support base of the second welding machine, the housing case 151 and the valve body housing 111, which have substantially the same outer diameter, are gripped as a whole. With the axes of the housing case 151 and the valve body housing 111 aligned, welding is performed on the lower end surface of the housing case 151 and the joint portion 111d of the valve body housing 111. As a result, a second bead is formed on the joint portion 111d of the housing case 151 and the valve body housing 111, adjacent to the first bead described above.

In this way, by providing multiple guide portions 133c (protrusions 133a) and multiple recesses 133b on the outer circumference of the fixing bracket 133, for example, a disc shape, the contact surfaces of the guide portions 133c abut against the inner circumferential surface 151b of the housing case 151, and the fixing bracket 133 and the valve body housing 111 can be welded and fixed together by the welded portions 133d formed in the recesses 133b that do not abut the inner circumferential surface 151b of the housing case 151. Since the weld beads formed by the welded portions 133d do not interfere with the inner circumferential surface 151b of the housing case 151, the valve body housing 111 and the housing case 151 can be in contact with each other without gaps, maintaining coaxiality and being fixed together.

In the above example, it is not necessary for all the contact surfaces of the guide portions 133c to contact the inner surface of the housing case 151. The end of the housing case 151 and the end of the valve body housing 111 may be brought into close contact without all the contact surfaces of the guide portions 133c contacting the inner surface of the housing case 151, thereby maintaining coaxiality between the fixing bracket 133 and the housing case 151. This is because the contact surfaces of the guide portions 133c act as mechanical stoppers, preventing the amount of axial misalignment between the housing case 151 and the valve body housing 111 from moving from a range where the magnet rotor 141 does not contact the inner circumferential surface 151b of the housing case 151 to a range where it does, thus preventing the housing case 151 from shifting.

In this example, four protrusions 133a (guide portions 133c) are provided on the fixing bracket 133. However, as long as coaxiality with the housing case 151 is maintained, it is sufficient to provide them in two or more locations while satisfying the above conditions. The second to fourth embodiments (modified versions) of the fixing bracket will be described below with reference to Figures 3(a) to 3(c).

Figure 3(a) shows another example of the shape of the fixing bracket, Figure 3(b) shows yet another example of the shape of the fixing bracket, and Figure 3(c) shows yet another example of the shape of the fixing bracket.

As shown in Figure 3(a), the fixing bracket 133A as the second embodiment has three protrusions 133Aa (hereinafter also referred to as guide portions 133Ac), and three recesses 133Ab are formed between the circumferential protrusions 133Aa. The three protrusions 133Aa are each formed at equal angular intervals, for example, 120° intervals. The width W of each protrusion 133Aa along the circumferential direction is set to be the same as one another. The recesses 133Ab are each formed at equal angular intervals, for example, 120° intervals. The length of the arcuate surface portion forming the recesses 133Ab along the circumferential direction is set to be the same as one another. Furthermore, as shown in Figure 3(a), the contact surface of the guide portion 133Ac, which abuts the inner circumferential surface of the housing case 151, is located at the intersection of a line that divides the circumference of the central axis CL of the fixing bracket 133A into three equal angles, and a virtual circle (a common circle where the aforementioned contact surfaces exist, similar to the virtual circle shown in Figure 2(c)). This satisfies the conditions for maintaining the aforementioned coaxiality.

In this case, the recess 133Ab is formed from an arcuate surface portion extending in the circumferential direction of the fixing bracket 133 and slanted surfaces connected to both ends of the arcuate surface portion and reaching the contact surface of the guide portion 133Aa. If, for example, the entire arcuate surface portion of the recess 133Ab is fillet-welded and the slanted surfaces are not welded, the welded arcuate surface portion will form the welded portion 133Ad.

Furthermore, as shown in Figure 3(b), the fixing bracket 133B as the third embodiment has a narrow protrusion 133Ba1 (hereinafter also referred to as the guide portion 133Bc) with a width W and a protrusion 133Ba2 consisting of an arcuate surface portion having a central angle of approximately 120° along the circumferential direction, positioned opposite each other. Between the two protrusions 133Ba1 and 133Ba2, there are two recesses 133Bb, which include arcuate surfaces formed along the circumferential direction. The circumferential lengths (surface areas) of the contact surfaces of the two protrusions 133Ba1 and 133Ba2 are different and not equal. Furthermore, as shown in Figure 3(b), the contact surface of the guide portion 133Bc, which abuts the inner circumferential surface 151b of the housing case 151, is located at the intersection of a line that divides the circumference of the central axis CL of the fixing bracket 133B into three equal angles, and a virtual circle (a common circle where the aforementioned contact surfaces exist, similar to the virtual circle shown in Figure 2(c)). This satisfies the conditions for maintaining the aforementioned coaxiality.

In this case, the recess 133Bb is formed from an arcuate surface portion extending in the circumferential direction of the fixing bracket 133 and slanted surfaces extending from both ends of the arcuate surface portion to the contact surface of the guide portion 133Bc. If, for example, the entire arcuate surface portion of the recess 133Bb is fillet-welded and the slanted surfaces are not welded, the welded arcuate surface portion will form the welded portion 133Bd.

Furthermore, as shown in Figure 3(c), in the fixing bracket 133C as the fourth embodiment, two recesses 133Cb are formed opposite each other on the remaining portion, excluding the two opposing protrusions 133Ca (hereinafter also referred to as guide portions 133Cc). The contact surfaces of the two protrusions 133Ca are formed by arcuate surfaces having the same central angle. The outer circumferential surfaces forming the two recesses 133Cb are formed from curved surfaces having the same shape. Also, as shown in Figure 3(c), the contact surface of the guide portion 133Cc that contacts the inner circumferential surface 151b of the housing case 151 is located at the intersection point of a virtual circle and a line that divides the circumference of the central axis CL of the fixing bracket 133C into four equal parts at equal angles. This satisfies the conditions for maintaining coaxiality.

In this case, the recess 133Cb is formed from a curved surface portion extending circumferentially from the fixing bracket 133 and slanted surfaces extending from both ends of the curved surface portion to the contact surface of the guide portion 133Ca. If, for example, the entire curved surface portion of the recess 133Cb is fillet-welded and the slanted surfaces are not welded, the welded curved surface portion will form the welded portion 133Cd.

By using the second to fourth embodiments (modified versions) of the fixing bracket 133, such as fixing brackets 133A, 133B, and 133C, the valve body housing 111 and the housing case 151 will be in contact without any gaps, just as when using the fixing bracket 133 shown in Figure 2(a), thus maintaining coaxiality.

As described above, according to the first embodiment of the present invention, the electric valve 100, by providing a plurality of guide portions 133c and a plurality of welded portions 133d along the outer circumference of the fixing bracket 133, interference between the weld bead that may occur at the welded portion and the housing case 151 can be prevented. The valve body housing 111 and the housing case 151 can be fixed in contact with each other without gaps, maintaining coaxiality, and reducing manufacturing control requirements.

The operation of the electric valve 100 configured in this manner will now be explained.

When driving the electric valve 100, the process begins by supplying a drive pulse signal to the stator. This causes the magnet rotor 141 to rotate according to the number of pulses, and consequently, the rotor shaft 131 rotates. The screw connection between the male threaded portion 131a of the rotor shaft 131 and the female threaded portion 132b of the female threaded member 132 causes the rotor shaft 131 to rotate and move along the central axis CL.

To close the electric valve 100, the rotor shaft 131 must be moved downward. After the needle 121 contacts the valve seat 112, further downward movement of the rotor shaft 131 compresses the valve spring 122 via the spring retainer 123. The needle 121 is then pressed against the valve seat 112 by the reaction force of the valve spring 122, ensuring that the electric valve 100 is reliably closed.

At this time, the needle 121 is pressed against the valve seat 112 via the spring retainer 123 and valve spring 122. Therefore, the frictional resistance of the seating surface becomes greater than the frictional resistance between the rotor shaft 131 and the highly slippery spring retainer 123. As a result, the rotating rotor shaft 131 slides against the spring retainer 123, suppressing the transmission of rotation to the needle case 125 and the needle 121. This suppresses wear between the needle 121 and the valve port 112a. Furthermore, because the rotor shaft 131 is pushed in, the washer 124 descends along with the flange portion 131b of the rotor shaft 131. The upper surface of the washer 124 becomes non-contact with the lower end surface of the opening end 125a of the needle case 125, and the rotation of the needle case 125 also stops.

Next, to return the electric valve 100 from the closed state to the open state, it is necessary to rotate the rotor shaft 131 in the reverse direction and move it upward. As the rotor shaft 131 rises, the valve spring 122 extends via the spring retainer 123. At this time, the needle 121 maintains contact with the valve seat 112. As the rotor shaft 131 moves further upward, the flange portion 131b of the rotor shaft 131 contacts the inner surface of the opening end 125a of the needle case 125 via the washer 124, and the needle case 125 is lifted while rotating. When the needle case 125 is lifted, the needle 121 fixed to it also moves upward, and the needle 121 and the valve port 112a of the valve seat 112 become non-contact, and the electric valve 100 is controlled to the open state.

In this configuration, the needle case 125 and needle 121 are driven by the rotor shaft 131 via a highly slippery washer 124. Therefore, the transmission of the rotor shaft 131's rotation to the needle case 125 and needle 121 is suppressed. This reduces wear between the needle 121 and the valve port 112a.

Next, a second embodiment of the electric valve according to the present invention will be described.

Figure 4 schematically shows the configuration of a second embodiment of the electric valve according to the present invention, along with the piping. Figure 5 is an enlarged cross-sectional view showing a magnified view of the V portion shown in Figure 4.

As shown in Figures 4 and 5, the configuration of the electric valve 200 differs from that of the electric valve 100, which has a fixing bracket 133, in that it includes a stepped fixing bracket 233 that is insert-molded into the female thread member 233. More specifically, the outer circumference of the metal, roughly disc-shaped stepped fixing bracket 233 has a contact surface that abuts against the inner circumferential surface 151b of the housing case 151, and has a stepped portion consisting of a convex portion 233a (hereinafter also referred to as a guide portion 233c) that protrudes outward, and a recess 233b that forms a gap in the portion surrounded by the inner circumferential surface 151b of the housing case 151 and the upper end surface of the valve body housing 111. A part of the upper end surface of the valve body housing 111 that forms the recess 233b (joint portion 111d) and a part of the lower end of the stepped fixing bracket 233 supported by the upper end surface of the valve body housing 111 form a welded portion 233d, as shown in Figure 5.

Furthermore, since the other components of the electric valve 200 are the same as those of the electric valve 100 described above, the same reference numerals are used for the same components, and their redundant explanations are omitted.

As shown in Figures 4 and 5, the stepped portion of the aforementioned stepped fixing bracket 233 is formed in the thickness direction along the central axis CL of the electric valve 200. The recess 233b, which is close to the central axis CL, is formed on the valve body housing 111 side, below the fixing bracket 233, because the lower end surface of the fixing bracket 233 is fillet-welded to the joint 111d of the valve body housing 111. Furthermore, the contact surface of the guide portion 233c, which is further from the central axis CL than the recess 233b, contacts the inner circumferential surface 151b of the housing case 151, and is therefore formed on the housing case 151 side, above the fixing bracket 233.

Note that, in this case, it is not necessarily required that the entire contact surface of the protrusion 233a contacts the inner circumferential surface 151b of the housing case 151.

Furthermore, as in the first embodiment, the condition for the guide portion 233c is that the stepped fixing bracket 233 is fitted onto the inner circumferential surface 151b of the housing case 151 so that the contact surface of the guide portion 233c contacts the inner circumferential surface 151b of the housing case 151. The guide portion 233c only needs to maintain coaxiality (coaxiality, concentricity) between the housing case 151 and the valve body housing 111 to the extent that interference between the inner circumferential surface of the housing case 151 and the rotating magnet rotor 141 is prevented. Therefore, the diameter of the contact surface of the guide portion 233c is set to be larger than the outer diameter of the magnet rotor 141 and smaller than the inner diameter of the inner circumferential surface 151b of the housing case 151 (outer diameter of magnet rotor 141 < diameter of contact surface < inner diameter of housing case 151).

Furthermore, the lower end portion that forms part of the recess 233b (excluding the guide portion 233c mentioned above) and the joint portion 111d of the valve body housing 111 are welded together. As a result, the welded portion 233d is formed by the lower end portion that forms the recess 233b in the stepped-edge fixing bracket 233 and the joint portion 111d of the valve body housing 111.

Furthermore, it is not necessary to make the entire recess 233b into a welded portion 233d; a portion of the recess 233b may be welded, or it may be fixed by welding using multiple spot welds or multiple spot fillet welds.

Furthermore, the welded portion 233d cannot be positioned inside the inner diameter of the annular joint portion 111d of the valve body housing 111. This is because the fixing bracket 233 and the valve body housing 111 cannot come into contact, making welding and fixing impossible. Additionally, the welded portion 233d must be formed in a position where the weld bead 233w generated by welding to the valve body housing 111 does not interfere with the housing case 151.

Furthermore, the protrusions 233a may be provided continuously around the entire circumference, or they may not be continuous around the entire circumference, but may be interrupted in multiple sections. In such cases, the contact surface of the guide portion 233c shall have at least one intersection point where a line (N = an integer of 3 or more) that divides the circumference of the central axis of the fixing bracket into N equal parts at equal angles intersects with a virtual circle similar to the virtual circle shown in Figure 2(c).

However, if the protrusion 233a is provided around the entire circumference, the protrusion 233a becomes circular, making manufacturing easier and thus reducing manufacturing time.

Furthermore, this embodiment can also be taken in the following form, and this form is also within the scope of application of the present invention. In the stepped-edge fixing bracket, for example, a circular disc serving as a guide portion is formed on the housing case 151 side, and a smaller circular disc, smaller in diameter than this disc, is formed coaxially and integrally with the larger circular disc on the valve body housing 111 side, with a welded portion formed on the smaller disc.

As described above, the electric valve 200 of the second embodiment of the present invention also provides the same effects as the first embodiment, while also having the effect of reducing manufacturing man-hours.

In this invention, the valve body housing 111 and the fixing bracket 133, which are welded, have been described as being made of metal. However, the invention is not limited to this, and for example, a weldable thermoplastic resin may be used. Furthermore, while the fixing brackets 133 and 233 have been described as being disc-shaped, the invention is not limited to this, and as shown in Figure 7, a plate material with other shapes, such as a hexagon or other polygon, can be used as the fixing bracket 333.

As described above, the present invention provides an electric valve and a refrigeration cycle system including the same, which can solve the aforementioned conventional problems by maintaining coaxiality when fixing the valve body housing and the housing case with a simple component structure, thereby reducing manufacturing control.

CL Central axis 11 First joint 12 Second joint 100, 200 Motorized valve 110 Valve body 111 Valve body housing 111A Valve chamber 111b First port 111c Second port 111d Joint 112 Valve seat 112a Valve port 120 Needle section 121 Needle 122 Valve spring 123 Spring retainer 123a Spring engagement section 124 Washer 125 Needle case 125a Open end 130, 230 Rotor shaft rotating section 131 Rotor shaft 131a Male threaded section 131b Flange section 132, 232 Female threaded members 132A, 232A Guide chamber 132b, 232b Female threaded section 132c, 232c Pressure equalization holes 133, 133A, 133B, 133C, 233 Fixing brackets 133a, 133Aa, 133Ba1, 133Ba1, 133Ca, 233a Protrusions 133b, 133Ab, 133Bb, 133Cb, 233b Recesses 133c, 133Ac, 133Bc, 133Cc, 233c Guide parts 133d, 133Ad, 133Bd, 133Cd, 233d Welded parts 140 Rotor shaft drive part 141 Magnet rotor 141A Rotor chamber 141b Engaging projection 142 Rotor fixing member 143 Rotation stopper spring 144 Movable stopper member 150 Exterior part 151 Housing case 151a Dimple 152 Rotor support member 152a Umbrella-shaped portion 152b Cylindrical portion 152c Engaging recess 153 Cylindrical member 300 Refrigeration cycle system 310 Outdoor unit 311 Expansion valve 312 Outdoor heat exchanger 313 Flow path switching valve 314 Compressor 315 Indoor heat exchanger 320 Indoor unit

Claims (3)

A valve body unit comprising a valve body that controls the opening and closing of a valve port,
The valve body unit includes an electromagnetic actuator comprising a rotor shaft and a magnetic rotor that operates a drive mechanism causing the valve body to move closer to or further away from the valve port in order to adjust the flow rate of fluid passing between the end of the valve body and the periphery of the valve port.
A female threaded member that rotatably supports the rotor shaft,
The valve body housing to which the female threaded member is fixed,
A fixing bracket having an outer peripheral edge that protrudes from the outer circumference of the female thread member in a direction perpendicular to the central axis of the rotor shaft, and which is fixed to the female thread member and welded to the peripheral edge of the opening upper surface of the valve body housing to fix the female thread member,
The electromagnetic actuator comprises a rotor shaft and a magnet rotor, and a housing case for housing them.
The fixing bracket comprises a plurality of guide portions formed on the outer peripheral edge concentric with the central axis of the housing case and spaced apart along the circumferential direction of the fixing bracket, each having a contact surface that protrudes toward the inner circumferential surface of the housing case; a plurality of recesses between the plurality of guide portions that are recessed in the direction of the central axis of the fixing bracket more than the contact surface of the guide portions; and welded portions formed in the recesses that are welded and fixed to the upper surface of the opening of the valve body housing.
The recess consists of an arcuate surface portion extending in the circumferential direction of the fixing bracket and inclined surfaces connected to both ends of the arcuate surface portion and reaching the contact surface of the guide portion.
An electric valve characterized in that the radius of curvature of the outer surface forming the arcuate surface of the recess is set to be smaller than the radius of curvature of the contact surface of the guide portion . The electric valve according to claim 1, characterized in that the contact surface of the guide portion is formed to lie on the circumference of a common virtual circle centered on the central axis of the rotor shaft, and the diameter of the virtual circle is set to be larger than the outer diameter of the magnet rotor and smaller than the inner diameter of the inner circumferential surface of the housing case. A refrigeration cycle system comprising a compressor, a condenser, an expansion valve, and an evaporator, characterized in that the electric valve described in claim 1 or claim 2 is used as the expansion valve.