Valve device and jig

Abstract

The present invention aims to provide a valve device, an electric valve, and a refrigeration cycle system that can reduce vibration and noise when the drive unit rotates. [Solution] The valve device 1 comprises a valve body 10, a female threaded member 40, and a male threaded member 60. The female threaded member 40 and the male threaded member 60 are screwed together to form a feed screw mechanism. The female threaded member 40 has a first female threaded member 41 and a second female threaded member 54, which are separate from each other, and each of the first female threaded member 41 and the second female threaded member 54 is screwed together with the male threaded member 60. The first female threaded member 41 and the second female threaded member 54 are connected so as not to rotate relative to each other about an axis L and so as to be movable relative to each other in the direction of the axis L, and are biased relative to each other in the direction of the axis L by a coil spring 58.

Description

Technical Field

[0001] The present invention relates to a valve device and a jig.

Background Art

[0002] There is known a valve device (electric valve) including a valve body (valve housing) having a valve chamber inside, a support member (female screw holder) fixed to the valve body, a female screw member fixed to the support member, a male screw member (rotor shaft) rotationally driven by a drive unit (stepping motor), and a valve member (valve holder and valve body) connected to the tip side of the male screw member (for example, see Patent Document 1). In this valve device, a feed screw mechanism is configured to move the valve member forward and backward in the axial direction by rotationally driving the male screw member that engages with the female screw member.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the conventional valve device as described above, for example, like the electric valve shown in FIG. 4 of Patent Document 1, the threads of the engaging female screw member 31 and rotor shaft (male screw member) 41 slide on each other. However, a predetermined clearance is provided between the threads (sliding portions) to stabilize the operability, which has caused vibration and noise when the drive unit rotates.

[0005] An object of the present invention is to provide a valve device and a jig capable of reducing vibration and noise when the drive unit rotates.

Means for Solving the Problems

[0006] To solve the aforementioned problems and achieve the objective, the valve device of the present invention comprises a valve body having a valve chamber inside, a fixing screw member supported by the valve body, a drive screw member screwed into the fixing screw member and rotationally driven by a drive unit, and a valve member connected to the drive screw member, wherein the fixing screw member comprises a cylindrical first member extending from one side in the axial direction to the other side in the axial direction, and a cylindrical second member housed inside the first member, and the side wall of the first member has a communication hole formed therein that opens to the other side in the axial direction of the housed second member and communicates with the inside and outside of the first member.

[0007] Furthermore, it is preferable that the inner circumferential surface of the first member is provided with a cylindrical guide portion into which the second member is inserted from the other side in the axial direction toward the one side in the axial direction, and that the communication hole opens near the end of the guide portion on the other side in the axial direction.

[0008] Furthermore, it is preferable that at least one pair of communication holes are provided, spaced apart in the circumferential direction around the axis.

[0009] Furthermore, the jig of the present invention is a jig used when assembling the valve device, and is characterized by comprising a restricting portion that is inserted into the communication hole and extends in a direction intersecting the axis, wherein the restricting portion restricts the displacement of the second member, which is housed in the guide portion, to the other side in the axial direction.

[0010] Furthermore, it is preferable that the restricting portion is composed of one end and the other end of the overall U-shaped main body, and that at least one pair of the communication holes can be inserted into each of the one end and the other end. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a valve device and jig that can reduce vibration and noise when the drive unit rotates. [Brief explanation of the drawing]

[0012] [Figure 1] A longitudinal cross-sectional view of a valve device according to the first embodiment of the present invention, cut along the axis of the needle portion. [Figure 2] (A) to (D) are schematic diagrams showing variations in the rotation restricting portion of the second female thread member. [Figure 3] An enlarged and simplified cross-sectional view of the main parts of the valve device shown in Figure 1. [Figure 4] (A) to (D) are schematic diagrams showing the assembly procedure for the valve device. [Figure 5] (E) to (G) are schematic diagrams showing the steps in the valve assembly procedure from the step shown in Figure 4(D) onwards. [Figure 6] A longitudinal cross-sectional view of the valve device according to the second embodiment, cut along the axis of the needle portion. [Figure 7] An enlarged and simplified cross-sectional view of the main part of the valve device according to the second embodiment of Figure 6. [Figure 8] A longitudinal cross-sectional view of the valve device according to the third embodiment, cut along the axis of the needle portion. [Figure 9] Figure 8 is an enlarged cross-sectional view of the main part of the valve device according to the third embodiment. [Figure 10] A schematic diagram showing an example of the refrigeration cycle system of the present invention. [Modes for carrying out the invention]

[0013] The valve device 1 according to the first embodiment of the present invention will be described below with reference to Figures 1 to 5. The valve device 1 is a device that controls the flow rate of a fluid and is used, for example, as an electric valve that constitutes part of a refrigeration cycle system 100 (see Figure 10). In the following description, the direction along the axis L of the needle portion 88, which will be described later, will be referred to as the "axis L direction," one side of the axis L direction will be referred to as "one side L1," and the other side of the axis L direction will be referred to as "the other side L2." The direction intersecting the axis L direction will be referred to as the radial direction. This is merely for the convenience of explanation and does not necessarily limit the directions in which the valve device 1 is actually used.

[0014] The valve device 1 includes a valve body 10 formed into a cylindrical shape by machining a metal material such as stainless steel or brass. The inside of the valve body 10 constitutes a valve chamber 11. A first port 12 is formed in the side wall of the valve body 10, penetrating radially, and a primary joint pipe 13 is attached to which the inside communicates with the valve chamber 11 via the first port 12. A cylindrical second port 14 is formed in the bottom wall of the valve body 10 (the wall portion on the other side L2), opening into the valve chamber 11 with axis L as the center. The peripheral edge of the opening on one side L1 (valve chamber 11 side) of the second port 14 constitutes a valve seat portion 15. The diameter of the second port 14 expands towards the other side L2, and the end on the other side L2 opens to the outside. A cylindrical portion 16 is formed on the other side L2 surface of the bottom wall of the valve body 10, projecting toward the other side L2, and a secondary joint pipe 16a is attached inside the cylindrical portion 16. The inside of the secondary fitting pipe 16a is in communication with the valve chamber 11 via the second port 14.

[0015] An opening 17 is formed in the upper wall (the wall portion on one side L1) of the valve body 10, penetrating in the direction of the axis L. A cylindrical valve guide member 18 is press-fitted into the inner circumferential surface of the opening 17 and fixed by crimping. A valve guide hole 18a is formed in the center of the valve guide member 18, penetrating in the direction of the axis L, and the needle portion 88 of the valve member 80, which will be described later, is inserted through the valve guide hole 18a. A cylindrical rim 19 is formed on the opening edge on one side L1 of the opening 17, rising up on one side L1. A support member 20 is assembled to the outer circumferential surface of the rim 19. The support member 20 is formed in a cylindrical shape using a metal material such as stainless steel or brass, and is fixed to the valve body 10 by crimping the rim 19 from the radially outward direction and by brazing the end face on the other side L2 to the end face on one side L1 of the valve body 10.

[0016] One side L1 of the support member 20 is open in the direction of the axis L, and on the opening end face thereof, a case 30 formed in a bottomed cylindrical shape from a metal material such as stainless steel is airtightly fixed by fixing its opening edge by welding or the like. A female screw member 40 (fixing screw member) is attached and supported on the inner peripheral surface of the opening of one side L1 of the support member 20. The female screw member 40 includes a first female screw member 41 (first member) and a second female screw member 54 (second member). The first female screw member 41 includes a press-fitting portion 42, a flange portion 43, a holder guide portion 44, and a shaft guide portion 46 in order from the other side L2 toward the one side L1.

[0017] The press-fitting portion 42 is formed in a columnar shape extending in the direction of the axis L using a resin material and is press-fitted into the inner peripheral surface of the opening of one side L1 of the support member 20. The flange portion 43 is formed in an annular shape using a metal material and is integrally formed with the press-fitting portion 42 by insert molding. The end face on the other side L2 of the flange portion 43 is fixed to the end face of one side L1 of the support member 20 by welding or the like. The holder guide portion 44 is continuous with the press-fitting portion 42 and extends along the axis L to the one side L1. A holder guide hole 45 that penetrates the press-fitting portion 42 and opens to the other side L2 is formed at the center inside the holder guide portion 44, and a portion of the one side L1 of a valve holder 81 described later is accommodated in the holder guide hole 45.

[0018] The shaft guide portion 46 is continuous with the holder guide portion 44, extends along the axis L to one side L1, and is formed in a cylindrical shape. A spiral guide groove 47 is formed on the outer wall surface of the shaft guide portion 46, and a coiled slider 48 is installed in the guide groove 47. A claw portion 49 that protrudes radially outward is formed on the slider 48, and the claw portion 49 can abut against a magnet protrusion 63 of a magnet rotor 62, which will be described later, around the axis L. At the center of the shaft guide portion 46, a first threaded hole 50 that extends in the direction of the axis L and opens to one side L1, and a guide portion 52 that is continuous with the first threaded hole 50, extends in the direction of the axis L, and opens to the other side L2 are formed. A first female thread 51 (female thread portion) is formed on the inner peripheral surface of the first threaded hole 50. The first female thread 51 is screwed with a male thread 64 of a male threaded member 60 (driving threaded member), which will be described later. The guide portion 52 is formed with an inner diameter larger than that of the first threaded hole 50 and extends to the other side L2. The inner wall surface (inner circumference) of the guide portion 52 has a shape along the outer peripheral shape of the second female threaded member 54, thereby constituting a fitting portion 53 that fits into a rotation restricting portion 57 (fitting portion), which will be described later.

[0019] The second female thread member 54 is provided separately from the first female thread member 41. The second female thread member 54 has a cylindrical tubular portion 54a extending in the axial direction L and is housed within the guide portion 52. A second threaded hole 55 penetrating in the axial direction L is formed in the center of the tubular portion 54a, and a second female thread 56 is formed on the inner circumferential surface of the second threaded hole 55. The second female thread 56 is screwed onto the male thread 64, similar to the first female thread 51 described above. Thus, the female thread member 40 is composed of a first female thread member 41 and a second female thread member 54, which are separate from each other, and each of the first female thread member 41 and the second female thread member 54 is screwed onto the male thread member 60, which will be described later as a drive screw member. A rotation restricting portion 57 (fitting portion) is formed on the outer circumferential surface of the cylindrical portion 54a of the second female thread member 54, extending along its entire length in the direction of the axis L, thereby defining the outer circumferential shape of the second female thread member 54. The rotation restricting portion 57 is a part that restricts the rotation of the second female thread member 54 around the axis L relative to the first female thread member 41, and can be configured in various shapes as illustrated in Figures 2(A) to (D), and can be fitted into the aforementioned fitting portion 53.

[0020] For example, the rotation restricting portion 57 may be composed of a first surface 57a (D-cut portion, double-chamfered portion) along the axis L and an arc-shaped second surface 57b (D-cut portion, double-chamfered portion) extending around the axis L, as shown in Figure 2(A), which constitute the outer circumferential surface of the second female thread member 54. That is, the rotation restricting portion 57 may be formed by double-chamfering the second female thread member 54 to a D-shape in plan view. Alternatively, the rotation restricting portion 57 may be composed of a projection 57c that protrudes radially outward from the outer circumferential surface of the second female thread member 54, as shown in Figure 2(B), or of a concave keyway 57d that recesses radially inward, as shown in Figure 2(C). When the rotation restricting portion 57 is composed of a projection 57c, it is preferable to provide a keyway, which is a recess (not shown) corresponding to the projection 57c, on the side of the fitted portion 53 described above. On the other hand, when the rotation restricting portion 57 is made of a keyway 57d, it is preferable to provide a protrusion 53a on the mating portion 53 side that fits into the keyway 57d, as shown in Figure 2(C). Alternatively, the rotation restricting portion 57 may be made of multiple surfaces 57e along the axis L, as shown in Figure 2(D), and may have a polygonal shape when viewed from above. In other words, the outer surface of the second female screw member 54 may be made of a polygonal shape. In this case, a polygonal hole is provided on the mating portion 53 side, and the rotation restricting portion 57, which has a polygonal shape when viewed from above, fits into this hole.

[0021] With this configuration, the rotation restricting portion 57 fits into the fitted portion 53, restricting the rotation of the second female thread member 54 around the axis L. In other words, the inner circumference of the guide portion 52 and the outer circumference of the second female thread member 54 are fitted together in a way that prevents relative rotation around the axis L. Furthermore, the rotation restricting portion 57 is configured to slide against the fitted portion 53 in the direction of the axis L, thereby guiding the second female thread member 54 in the direction of the axis L. Thus, the second female thread member 54 is guided in the direction of the axis L by the guide portion 52, and the inner circumference of the guide portion 52 and the outer circumference of the second female thread member 54 are fitted together in a way that prevents relative rotation around the axis L. In this embodiment, the inner circumference of the guide portion 52 is used as the fitting portion 53, and the rotation restricting portion 57 is provided on the outer circumference of the second female screw member 54. However, conversely, the rotation restricting portion 57 may be provided on the guide portion 52 side, and the shape of the outer circumference of the second female screw member 54 may be made to conform to the rotation restricting portion 57.

[0022] In other words, a rotation restricting portion 57 is provided on one of the inner circumference of the guide portion 52 and the outer circumference of the second female thread member 54, and the rotation restricting portion 57 is provided on the other of the inner circumference of the guide portion 52 and the outer circumference of the second female thread member 54, which is composed of a first surface 57a and a second surface 57b (D-cut portion, double-chamfered portion), a projection 57c, a keyway 57d, and a plurality of surfaces 57e (polygonal portion), and a fitting portion 53 is provided on the other of the inner circumference of the guide portion 52 and the outer circumference of the second female thread member 54 that fits into the rotation restricting portion 57. In the above description, it is stated that the inner circumference of the guide portion 52 and the outer circumference of the second female thread member 54 are fitted together so that they cannot rotate relative to each other around the axis L. However, in reality, there is a small gap between the rotation restricting portion 57 and the fitted portion 53 for fitting purposes. As a result, the inner circumference of the guide portion 52 and the outer circumference of the second female thread member 54 may rotate slightly relative to each other around the axis L due to this gap. This slight relative rotation is included in the "cannot rotate relative to each other" in this embodiment.

[0023] As shown in Figure 3, a coil spring 58 (biasing means) is positioned between the guide portion 52 and the second female thread member 54. Note that the coil spring 58, mainly shown in Figure 3 (or Figure 7), is not depicted in its actual spiral shape, but as a schematic diagram. One end L1 of the coil spring 58 abuts against the other end L2 of the guide portion 52, and the other end L2 of the coil spring 58 abuts against the one end L1 of the second female thread member 54. In other words, the coil spring 58 is provided between the first female thread member 41 and the second female thread member 54, extending from the end face of the first female thread member 41 in the axial direction L to the end face of the second female thread member 54 in the axial direction L. The coil spring 58 biases the first female thread member 41 and the second female thread member 54 in a direction away from each other along the axial direction L.

[0024] With the above configuration, the first female thread member 41 and the second female thread member 54 are connected so that they cannot rotate relative to each other around the axis L and can move relative to each other in the direction of the axis L, and are biased toward each other in the direction of the axis L by a coil spring 58. In this embodiment, the biasing means is made up of a coil spring 58, but it is not limited to this, and for example, the biasing means may be made up of a leaf spring combination made up of leaf springs. In the above description, it is stated that the first female thread member 41 and the second female thread member 54 are connected so that they can move relative to each other in the direction of the axis L, but "relatively movable" has the following meaning. In other words, when a force is generated that opposes the spring load of the coil spring 58, the first female thread member 41 and the second female thread member 54 are "relatively movable" in the axial direction L by the amount of thread play between the first female thread portion 51 of the first female thread member 41 and the male thread 64 of the male thread member 60 described later, or by the amount of thread play between the second female thread 56 of the second female thread member 54 and the male thread 64.

[0025] As shown in Figure 1, a male threaded member 60 (drive threaded member) is screwed into and connected to the female threaded member 40. The male threaded member 60 is a drive shaft that is rotationally driven around axis L by the drive unit 70, and extends in the direction of axis L through the first threaded hole 50 and the second threaded hole 55. A magnet rotor 62 is attached to one end L1 of the male threaded member 60 via a cylindrical bush 61. The magnet rotor 62 is formed in a cylindrical shape that extends in the direction of axis L, and together with a stator coil (not shown) installed on the outside of the case 30 described above, it constitutes an electric motor and is the drive unit 70 of the valve device 1. By being rotationally driven, the magnet rotor 62 is rotatable around axis L together with the male threaded member 60 and is also movable in the direction of axis L. A magnet projection 63 is formed on a part of the inner circumferential surface of the magnet rotor 62 as a projection that protrudes radially inward. The claw portion 49 of the slider 48 described above can contact the magnet projection 63 around axis L.

[0026] In this configuration, when the magnet rotor 62 rotates, the slider 48 rotates around the axis L in accordance with its rotation and is guided by the guide groove 47 to move to one side L1 or the other side L2. When the slider 48 comes into contact with the upper end or lower end of the guide groove 47, it can no longer rotate, and the rotation of the magnet rotor 62 stops. A male screw 64 is formed on the outer circumferential surface of the male screw member 60, which screws into the first female screw 51 and the second female screw 56. In this way, the first female screw 51 and the second female screw 56 (fixing screw member) and the male screw 64 (male screw member 60, driving screw member) are screwed together, and the rotational drive of the male screw member 60 configures a feed screw mechanism that moves the valve member 80, which will be described later, back and forth in the direction of the axis L.

[0027] A flange portion 65 projecting radially outward is formed at the lower end of the male threaded member 60, and the male threaded member 60 is connected to the valve member 80 via the flange portion 65. The valve member 80 comprises a valve holder 81 connected to the flange portion 65 and a needle valve 86 connected to the valve holder 81. The valve holder 81 is formed in a cylindrical shape and extends in the axial direction L. The outer diameter of the valve holder 81 is formed to be slightly smaller than the inner diameter of the holder guide hole 45, thereby allowing the outer circumferential surface of the valve holder 81 to slide against the inner circumferential surface of the holder guide hole 45. A mounting hole 82 penetrating in the axial direction L is formed in the wall portion of one side L1 of the valve holder 81, and the lower end of the male threaded member 60, including the flange portion 65, is inserted through the mounting hole 82. An annular washer 83 is installed between the inner surface of the wall portion of one side L1 of the valve holder 81 and the end face of one side L1 of the flange portion 65.

[0028] A columnar spring retainer 84 is installed inside the valve holder 81. One end face L1 of the spring retainer 84 abuts against the other end face L2 of the washer 83. A spring 89 is installed around the spring retainer 84, covering it in the circumferential direction. One end L1 of the spring 89 abuts against the other end face L2 of the spring retainer 84, and the other end face L2 of the spring 89 abuts against the one end face L1 of the flange 87, which will be described later. This configuration biases the needle valve 86 toward the other side L2. The other end L2 of the valve holder 81 opens in the axial direction L, and an annular retaining member 85 is fixed to this opening. The needle valve 86 comprises a flange 87 and a needle portion 88. The flange 87 is located inside the valve holder 81, and the other end face L2 is in contact with the end face L1 of the retaining member 85 when the needle portion 88 is not seated on the valve seat portion 15. The needle portion 88 is formed in a cylindrical shape and extends in the axial direction L into the valve chamber 11 through the valve guide hole 18a of the valve guide member 18 described above. The other end L2 of the needle portion 88 is formed in a substantially conical shape that narrows in diameter towards the other L2.

[0029] Next, the assembly of the female thread member 40 and the male thread member 60 in the valve device 1 will be described. Figures 4(A) to 4(D) are schematic diagrams showing the assembly procedure of the valve device 1. Figures 5(E) to 5(G) are schematic diagrams showing the steps from the step shown in Figure 4(D) onwards in the assembly procedure of the valve device 1. First, as shown in Figure 4(A), the first female thread member 41 is positioned with the other side L2 located on the upper side in Figure 4. Next, as shown in Figure 4(B), the coil spring 58 is inserted into the first female thread member 41 from the holder guide hole 45 side and positioned in the guide portion 52, and then the second female thread member 54 is inserted into the first female thread member 41. Note that, at this time, the biasing force of the coil spring 58 biases the second female thread member 54 toward the other side L2, so simply inserting the second female thread member 54 into the first female thread member 41 will not position the second female thread member 54 in the guide portion 52. Therefore, as shown in Figure 4(C), the second female thread member 54 is pushed into the guide portion 52 using a rod-shaped first pressing jig 45a that extends in the direction of the axis L.

[0030] Specifically, the male thread 45b formed on one end L1 of the first pressing jig 45a is screwed into the second female thread 56 of the second female thread member 54, thereby integrating the first pressing jig 45a and the second female thread member 54, and in this state the second female thread member 54 is pushed into one side L1. As a result the rotation restricting portion 57 of the second female thread member 54 fits into the fitting portion 53 of the guide portion 52, and the second female thread member 54 is positioned inside the guide portion 52. Then, in this state, the second pressing jig 45c is installed to restrict the displacement of the second female thread member 54 to the other side L2. As shown in Figure 4(C), the second pressing jig 45c is formed by bending a metal material into a U shape, and each of its two tip portions is inserted into each of a pair of jig insertion holes 45d that penetrate the holder guide hole 45. When the second retaining jig 45c is inserted through the jig insertion hole 45d, as shown in Figure 4(D), even if the second female thread member 54 tries to displace to the other side L2, the displacement is restricted by contact with the second retaining jig 45c.

[0031] Therefore, after the second retaining jig 45c has been inserted into the jig insertion hole 45d, the first retaining jig 45a may be removed from the second female thread member 54. Next, as shown in Figure 5(E), the male thread member 60, which is integrated with the valve member 80 via the flange portion 65, is connected to the female thread member 40. First, the male thread member 60 is positioned so that one end L1 of the male thread member 60 is located on the lower side in Figure 5, and is brought closer to the female thread member 40 along the axis L direction. Then, the male thread 64 of the male thread member 60 is screwed into the second female thread 56 and the first female thread 51 in that order, and the male thread member 60 is moved to one side L1 until one end L1 of the male thread member 60 protrudes from one side L1 of the female thread member 40 and one side L1 portion of the valve holder 81 is housed in the holder guide hole 45, as shown in Figure 5(F). Then, after the male threaded member 60 has been attached to the female threaded member 40, the second retaining jig 45c is removed from the jig insertion hole 45d, as shown in Figure 5(G). This completes the assembly of the female threaded member 40 and the male threaded member 60 in the valve device 1.

[0032] Next, the operation of the valve device 1 will be described. In the valve device 1 configured as described above, when the electric motor of the drive unit 70 is driven, the magnet rotor 62 rotates around the axis L, and the male screw 64 is screwed by the lead screw mechanism, causing the magnet rotor 62 and the male screw member 60 to move back and forth in the direction of the axis L. As the male screw member 60 moves back and forth, the valve member 80 also moves back and forth in the direction of the axis L. As a result, for example, as shown in Figure 1, the needle portion 88 moves from a state where it is seated (or closest to) the valve seat portion 15 to one side L1 (separated), and the opening degree of the second port 14 increases. As a result, the flow rate of the fluid flowing through the primary fitting pipe 13, the first port 12, the valve chamber 11, the second port 14, and the secondary fitting pipe 16a increases. At this time, as shown in Figure 3, the first female screw member 41 and the second female screw member 54 are biased to move away from each other in the direction of the axis L. Therefore, the female thread member 40 (first female thread member 41, second female thread member 54) and the male thread member 60 can slide against each other in the axial direction L without clearance, and a load due to a biasing force in the axial direction L can always be applied to the sliding point between the female thread member 40 and the male thread member 60.

[0033] Then, when the magnet rotor 62 is rotated in the opposite direction from this state, the male screw 64 is screwed forward by the feed screw mechanism, causing the magnet rotor 62 and the male screw member 60 to move to the other side L2, and the needle portion 88 to seat on the valve seat portion 15. As a result, the second port 14 is closed. In this embodiment, the needle portion 88 seats on the valve seat portion 15 and closes the second port 14 when the needle portion 88 is displaced as far as the other side L2, but this is not the only example. This configuration can also be applied to a normally open type valve device 1 in which the needle portion 88 approaches the valve seat portion 15 but does not seat on it.

[0034] Next, the refrigeration cycle system 100 of the present invention will be described with reference to Figure 10. Figure 10 is a schematic diagram showing an example of the refrigeration cycle system of the present invention. In Figure 10, reference numeral 1 denotes an expansion valve using the valve device 1 (electric valve) described above, 200 denotes an outdoor heat exchanger mounted on an outdoor unit, 300 denotes an indoor heat exchanger mounted on an indoor unit, 400 denotes a flow path switching valve that constitutes a four-way valve, and 500 denotes a compressor. The valve device 1 (expansion valve), outdoor heat exchanger 200, indoor heat exchanger 300, flow path switching valve 400, and compressor 500 are connected by conduits as shown in the figure, and constitute a heat pump type refrigeration cycle. Note that the accumulator, pressure sensor, temperature sensor, etc. are not shown.

[0035] The flow path of the refrigeration cycle can be switched between two paths by the flow path switching valve 400: one for cooling operation and one for heating operation. During cooling operation, as shown by the solid arrows in Figure 10, the refrigerant compressed by the compressor 500 flows from the flow path switching valve 400 into the outdoor heat exchanger 200, which functions as a condenser. The liquid refrigerant flowing out of the outdoor heat exchanger 200 flows through the valve device 1, which acts as an expansion valve, into the indoor heat exchanger 300, which functions as an evaporator. On the other hand, during heating operation, as shown by the dashed arrows in Figure 10, the refrigerant compressed by the compressor 500 circulates in the following order: from the flow path switching valve 400 to the indoor heat exchanger 300, then to the valve device 1, which acts as an expansion valve, to the outdoor heat exchanger 200, and finally back to the compressor 500. The indoor heat exchanger 300 functions as a condenser, and the outdoor heat exchanger 200 functions as an evaporator.

[0036] As described above, according to the embodiment described, the coil spring 58 or leaf spring combination (biasing means) biases the first female screw member 41 (first member) and the second female screw member 54 (second member) of the female screw member 40 (fixing screw member) and male screw member 60 (driving screw member) toward each other in the axial direction L. Therefore, the female screw member 40 and the male screw member 60 slide toward each other in the axial direction L without clearance, and a load due to the biasing force in the axial direction L can be constantly applied to the sliding point between the female screw member 40 and the second female screw member 54. This load generates sliding resistance between the female screw member 40 and the male screw member 60, thereby reducing vibration and noise when the drive unit 70 rotates.

[0037] Furthermore, with this configuration, the coil spring 58 is provided between the first female threaded member 41 and the second female threaded member 54, whose relative positional relationship is less likely to change in the axial direction L due to screwing, and biases the first female threaded member 41 and the second female threaded member 54 toward each other in the axial direction L. Therefore, even if the male threaded member 60 is rotated and the valve member 80 is moved forward and backward in the axial direction L to change the opening degree of the second port 14, the expansion and contraction of the coil spring 58 in the axial direction L is suppressed in conjunction with this movement, and there is no need to provide space for such expansion and contraction. For example, in the structure of the valve device 1 of the first embodiment shown in Figure 1, if the coil spring 58 is positioned between the upper end of the male screw member 60 and the lower surface of the upper end of the case 30, as shown in Figure 1 of the aforementioned Patent Document 1, and biased toward the other side L2, then it would be necessary to extend the case 30 in the axial direction L to increase the overall length of the valve device 1, taking into account the space required for the expansion and contraction of the coil spring 58. However, in this configuration, the coil spring 58 biases the first female screw member 41 and the second female screw member 54 toward each other between the first female screw member 41 and the second female screw member 54, so it is not necessary to increase the overall length of the valve device 1. Therefore, it is possible to save space in the valve device 1. Furthermore, as described above, since the expansion and contraction of the coil spring 58 in the axial direction L is suppressed in conjunction with the forward and backward movement of the valve member 80, for example, even if the opening degree of the second port 14 changes, the load in the axial direction L due to the coil spring 58 can always be kept constant, and the effect of reducing vibration and noise as described above can be stably maintained. Therefore, in the valve device 1, which can reduce vibration and noise when the drive unit 70 rotates, space saving is achieved, and the reduced vibration and noise when the drive unit 70 rotates can be stably maintained. As described above, the coil spring 58 can be provided in particular from the end face in the axial direction L of the first female thread member 41 to the end face in the axial direction L of the second female thread member 54.

[0038] Furthermore, according to this embodiment, the inner circumference of the guide portion 52 and the outer circumference of the cylindrical portion 54a of the second female thread member 54 are fitted together along the entire length of the cylindrical portion 54a in the direction of the axis L, so that the entire circumference of the second female thread member 54 around the axis L is surrounded by the first female thread member 41 along the entire length of the axis L. Therefore, the first female thread member 41 and the second female thread member 54 can be connected more reliably so that they cannot rotate relative to each other around the axis L and can move relative to each other in the direction of the axis L. In addition, with this configuration, since the cylindrical portion 54a of the second female thread member 54 is guided by the guide portion 52 along its entire length in the direction of the axis L, the inclination of the second female thread member 54 with respect to the direction of the axis L can be suppressed compared to a configuration in which only a part of the total length of the cylindrical portion 54a in the direction of the axis L is guided by the guide portion 52. Therefore, it is possible to avoid malfunctions caused by an unintended increase in sliding resistance between the female thread member 40 and the male thread member 60 due to the tilt of the second female thread member 54.

[0039] Furthermore, according to this embodiment, the rotation restricting portion 57 (fitting portion) is composed of various shapes such as a first surface 57a (D-cut portion, double-chamfered portion) and a second surface 57b (D-cut portion, double-chamfered portion), a projection 57c, a keyway 57d, and multiple surfaces 57e (polygonal portion), and by fitting this rotation restricting portion 57 into the fitted portion 53, the first female thread member 41 and the second female thread member 54 can be connected so that they cannot rotate relative to each other around the axis L and can move relative to each other in the direction of the axis L.

[0040] Furthermore, according to this embodiment, the present invention can be applied to a configuration in which the fixing screw member is composed of a first female screw member 41 and a second female screw member 54, and the driving screw member is a male screw member 60.

[0041] Furthermore, according to this embodiment, in an electric valve in which the drive unit 70 is equipped with an electric motor, vibration and noise when the drive unit 70 rotates can be reduced. In this embodiment, an electric valve is exemplified as an example of the valve device 1, but electric valves also include, for example, an electronic expansion valve that opens and closes (or moves closer to, separates) the second port 14 with a stepping motor. Moreover, the valve device 1 is not limited to an electric valve, and may be a solenoid valve in which a plunger moves forward and backward with an electromagnetic coil, or a manual valve in which the valve member 80 is moved manually.

[0042] Furthermore, according to this embodiment, the refrigeration cycle system 100 can be configured using a valve device 1 that can reduce vibration and noise when the drive unit 70 rotates.

[0043] Next, a second embodiment of the present invention will be described. Figure 6 is a longitudinal cross-sectional view of the valve device 2 according to the second embodiment, cut along the axis L of the needle portion 88. Figure 7 is an enlarged and simplified cross-sectional view of the main part of the valve device 2 according to the second embodiment of Figure 6. The valve device 2 includes a valve body 10'. A valve guide portion 18' is formed on the valve body 10'. The valve guide portion 18' is formed in a columnar shape and extends from the center of the upper wall of the valve body 10' to one side L1. The valve guide portion 18' corresponds to the valve guide member 18 of the first embodiment, but differs from the valve guide member 18 in that it is formed integrally with the valve body 10'. A valve guide hole 18a is formed in the center of the valve guide portion 18', and the needle portion 88 of the valve member 80 is inserted through the valve guide hole 18a. A support recess 18b opening to one side L1 is formed in the center of the upper end of the valve guide portion 18'. The other end L2 of the male threaded member 60', which will be described later, is inserted into and fixed in the support recess 18b. In other words, in the second embodiment, the male threaded member 60' is fixed to the valve body 10 to constitute a fixed threaded member.

[0044] A support member 20 is assembled to the outer circumferential surface of the valve guide portion 18', and a case 30 is fixed to the opening edge of the support member 20. In the second embodiment, a support shaft 31 is attached to the center of the bottom of the case 30 (corresponding to the upper end of the valve device 1 in Figure 6), projecting outwards to the other side L2 along the axis L. A guide 32 is formed on the outer circumferential surface of the support shaft 31, forming a helical groove on the outer circumferential surface. A slider 33 that fits into the helical groove is installed on the guide 32. A claw portion 34 is formed on the slider 33, projecting radially outward, and the claw portion 34 abuts against the magnet projection 63' of the magnet rotor 62' around the axis L. In the second embodiment, the magnet projection 63' is formed extending from one end of one side L1 to the other side L1 of the magnet rotor 62'.

[0045] In the second embodiment, the male threaded member 60' is formed in a cylindrical shape extending in the axial direction L. A male thread 64 is formed on the outer circumferential surface of the male threaded member 60'. A drive shaft 66 extending in the axial direction L and a valve member 80 are inserted inside the male threaded member 60'. The drive shaft 66 extends in the axial direction L, and one end L1 of it protrudes from the male threaded member 60' to the other end L1. The valve member 80 comprises a cylindrical body portion 87' that abuts against the other end L2 of the drive shaft 66, and a needle portion 88 that is continuous with the body portion 87' and extends in the axial direction L through the valve guide hole 18a into the valve chamber 11. A female threaded member 40' is screwed into and connected to the male threaded member 60'. The female thread member 40' comprises a first female thread member 41' (first member) and a second female thread member 54' (second member).

[0046] The first female threaded member 41' is formed in a bottomed cylindrical shape and opens to the other side L2. The outer circumferential surface of the first female threaded member 41' is fixed to the inner circumferential surface of the magnet rotor 62', thereby integrating the first female threaded member 41' and the magnet rotor 62'. A first female thread 51' is formed on the inner circumferential surface of the first female threaded member 41', and the first female thread 51' is screwed into the male thread 64. A through hole 41'b is formed in the center of the bottom wall 41'a of the first female threaded member 41', penetrating in the direction of the axis L, and one end L1 of the drive shaft 66 is inserted through the through hole 41'b. The first female threaded member 41' is connected to the drive shaft 66 by a connecting member 90. The connecting member 90 includes a first support portion 91 positioned on the other side L2 of the bottom wall 41'a of the first female threaded member 41', and a second support portion 94 positioned on one side L1 of the bottom wall 41'a of the first female threaded member 41'. The first support portion 91 is fixed to the drive shaft 66 so as to be rotatable relative to it about an axis L and includes a cylindrical portion 92 that covers the drive shaft 66 in the circumferential direction, and a flange 93 that protrudes radially from one end L1 of the cylindrical portion 92.

[0047] A spring 89' is installed between the other end face L2 of the cylindrical portion 92 and the end face L1 of one side of the main body portion 87' of the valve member 80 described above, thereby biasing the valve member 80 toward the other side L2. The end face L1 of one side of the flange 93 abuts against the end face L2 of the other side of the bottom wall 41'a of the first female thread member 41'. The second support portion 94 is formed in a disc shape to cover the end of one side L1 of the drive shaft 66 in the circumferential direction and is fixed to the drive shaft 66 so as not to rotate relative to it around the axis L. The end face L2 of the other side of the second support portion 94 abuts against the end face L1 of the bottom wall 41'a of the first female thread member 41'. In this way, the flange 93 of the first support portion 91 and the second support portion 94 sandwich the bottom wall 41'a in the direction of the axis L, thereby connecting the first female thread member 41' and the magnet rotor 62' to the connecting member 90 and the drive shaft 66 so that they can rotate relative to each other around the axis L.

[0048] The second female thread member 54' is provided separately from the first female thread member 41', formed in a cylindrical shape, and housed in a guide portion 52' which is part of the inner circumferential surface of the magnet rotor 62'. A second female thread 56' is formed at the center of the second female thread member 54', and the second female thread 56' is screwed into the male thread 64. A coil spring 58 is positioned between the first female thread member 41' and the second female thread member 54'. One end L1 of the coil spring 58 abuts against the other end L2 of the first female thread member 41', and the other end L2 of the coil spring 58 abuts against the one end L1 of the second female thread member 54'. As a result, as shown in Figure 7, the coil spring 58 biases the first female thread member 41' and the second female thread member 54' toward each other along the axial direction L.

[0049] In the valve device 2 configured in this way, when the electric motor of the drive unit 70 is driven, the magnet rotor 62' rotates around the axis L, and the female screw member 40' (first female screw member 41', second female screw member 54') is screwed forward by the feed screw mechanism, causing the magnet rotor 62' and the female screw member 40' to move back and forth in the direction of the axis L. As a result of this back and forth movement, the connecting member 90 and the drive shaft 66 move back and forth in the direction of the axis L. As a result of the back and forth movement of the drive shaft 66, the valve member 80 moves back and forth, and the opening degree of the second port 14 changes. Thus, in the second embodiment, the female screw member 40' constitutes the drive screw member, and the drive screw member has a first member and a second member. As described above, the male screw member 60' constitutes the fixed screw member. According to this second embodiment, the present invention can also be applied to a configuration in which the drive screw member is composed of a first female screw member 41' and a second female screw member 54', and the fixing screw member is a male screw member 60', and the same functions and effects as in the first embodiment can be achieved.

[0050] Next, a third embodiment of the present invention will be described. Figure 8 is a longitudinal cross-sectional view of the valve device 3 according to the third embodiment, cut along the axis L of the needle portion 88. Figure 9 is an enlarged cross-sectional view of the main part of the valve device 3 according to the third embodiment of Figure 8. The valve device 3 of the third embodiment includes a male threaded member 600 and a female threaded member 700. The male threaded member 600 corresponds to the male threaded member 60' of the second embodiment, and the female threaded member 700 corresponds to the female threaded member 40' of the second embodiment. The configuration other than the male threaded member 600 and the female threaded member 700 is the same as in the second embodiment, so their description will be omitted or simplified. As shown in Figure 9, the male threaded member 600 includes a first male threaded member 601 (first member) and a second male threaded member 604 (second member). That is, in the third embodiment, the fixing screw member side includes the first member and the second member. The first male threaded member 601 is formed in a cylindrical shape extending in the direction of the axis L. A first male thread 602 is formed on the outer circumferential surface of the first male thread member 601, and the first male thread 602 is screwed into the female thread 701 of the female thread member 700, which will be described later. A first recess 603 is formed on the inner circumferential surface of the other side L2 of the first male thread 602, recessed into the one side L1.

[0051] The second male threaded member 604 is formed in a cylindrical shape extending in the axial direction L. The other end L2 of the second male threaded member 604 is inserted into and fixed in the support recess 18b of the valve guide portion 18' of the valve body 10'. A second male thread 605 is formed on the outer circumferential surface of the second male threaded member 604, and the second male thread 605 is screwed into the female thread 701 of the female threaded member 700. A second recess 606 is formed on the inner circumferential surface of one side L1 of the second male threaded member 604, recessed into the other side L2. A coil spring 58 is installed between the first recess 603 and the second recess 606. One end L1 of the coil spring 58 abuts against the bottom surface of the first recess 603, and the other end L2 of the coil spring 58 abuts against the bottom surface of the second recess 606. As a result, the coil spring 58 biases the first male threaded member 601 and the second male threaded member 604 in a direction that moves them away from each other along the axial direction L.

[0052] The first male threaded member 601 and the second male threaded member 604 are connected by an anti-rotation mechanism 607 so that they cannot rotate relative to each other around the axis L, but can move in the direction of the axis L. Various configurations can be used for the anti-rotation mechanism 607. For example, one projection protruding toward the other side L2 may be provided at the other end L2 of the first male threaded member 601, and two projections protruding toward the one side L1 may be provided at the one end L1 of the second male threaded member 604, with one projection sandwiched between the two projections to form the anti-rotation mechanism 607. Alternatively, two projections protruding toward the other side L2 may be provided at the other end L2 of the first male threaded member 601, and one projection protruding toward the one side L1 may be provided at the one end L1 of the second male threaded member 604, with one projection sandwiched between the two projections to form the anti-rotation mechanism 607.

[0053] Furthermore, a protrusion projecting in the axial direction L is provided on one end of the other side L2 of the first male thread member 601 and on one end of the one side L1 of the second male thread member 604, and a recess in the axial direction L is provided on the other end, forming a rotation-preventing mechanism 607 through interlocking of the protrusions and recesses. The number and arrangement of the protrusions, protrusions, and recesses are not particularly limited; for example, two sets of rotation-preventing mechanisms 607, each composed of protrusions and recesses, may be provided and arranged at positions 180° apart around the axis L. The female thread member 700 is formed in a bottomed cylindrical shape and opens to the other side L2. The outer circumferential surface of the female thread member 700 is fixed to the inner circumferential surface of the magnet rotor 62', thereby integrating the female thread member 700 and the magnet rotor 62'. A female thread 701 is formed on the inner circumferential surface of the female thread member 700, and the female thread 701 is screwed into the first male thread 602 and the second male thread 605. According to this third embodiment, the present invention can also be applied to a configuration in which the fixing screw member is composed of a first male screw member 601 and a second male screw member 604, and the driving screw member is a female screw member 700, and the same functions and effects as the first and second embodiments can be achieved.

[0054] The first, second, and third embodiments have been described in detail above with reference to the drawings, but the specific configuration is not limited to these embodiments, and any design changes, etc., that do not depart from the gist of the present invention are also included in the present invention. For example, in the first embodiment described above, the fixing screw member is composed of a first female screw member 41 and a second female screw member 54, and the driving screw member is composed of a male screw member 60. However, the invention is not limited to this, and the first female screw member 41 and the second female screw member 54 as the fixing screw member may be combined into one, and the male screw member 60 as the driving screw member may be divided into two. Specifically, the second female screw member 54 shown in Figure 1 may be omitted, and the fixing screw member may be composed of only the first female screw member 41.

[0055] Then, the male screw member 60 shown in Figure 1 is divided into a first male screw member fixed to the magnet rotor 62 and constituting one side L1 portion, and a second male screw member connected to the valve member 80 and constituting the other side L2 portion. The first male thread of the first male screw portion and the second male thread of the second male screw portion are screwed into the female thread 56 of the first female screw member 41, respectively. A coil spring 58 is interposed between the first male screw member and the second male screw member to integrate them. In this way, the first male screw member and the second male screw member constitute the drive screw member. In this configuration, when the electric motor of the drive unit 70 is driven, the magnet rotor 62 rotates around the axis L, and the first male screw member and the second male screw member are screwed by the feed screw mechanism, so that the magnet rotor 62, the first male screw member and the second male screw member move back and forth together in the direction of axis L. As a result of this forward and backward movement, the valve member 80 moves closer to or further away from the second port 14, thereby changing the opening degree of the second port 14.

[0056] Thus, the present invention may also be applied to a configuration in which the fixing screw member is the first female screw member 41 and the driving screw members are the first male screw member and the second male screw member. In any case, one of the fixing screw member and the driving screw member is configured to have a first member and a second member that are separate from each other, and each of the first member and the second member is screwed into the other of the fixing screw member and the driving screw member. Furthermore, in the first embodiment, a coil spring 58 or the like is placed between the first female screw member 41 and the second female screw member 54, and the coil spring 58 or the like biases the first female screw member 41 and the second female screw member 54 away from each other in the axial direction L. However, the present invention is not limited to this configuration, and the biasing means such as the coil spring 58 can be used in various arrangements as long as it can bias the first female screw member 41 and the second female screw member 54 in the axial direction L. [Explanation of symbols]

[0057] L axis 1 Valve device 10 Valve body 40 Female threaded member (fixing screw member) 41 First female threaded member (first member) 54 Second female threaded member (second member) 58 Coil spring (biasing means) 60 Male screw member (drive screw member) 70 Drive unit 80 Valve member

Claims

1. A valve device comprising: a valve body having a valve chamber inside; a fixing screw member supported by the valve body; a drive screw member screwed into the fixing screw member and rotationally driven by a drive unit; and a valve member connected to the drive screw member, The fixing screw member comprises a cylindrical first member extending from one side in the axial direction to the other side in the axial direction, and a cylindrical second member housed inside the first member. A valve device characterized in that a communication hole is formed in the side wall of the first member, which opens to the other side in the axial direction of the housed second member and communicates with the inside and outside of the first member.

2. The inner circumferential surface of the first member is provided with a cylindrical guide portion into which the second member is inserted from the other side in the axial direction toward the one side in the axial direction. The valve device according to claim 1, characterized in that the communication hole is opened near the other end of the guide portion in the axial direction.

3. The valve device according to claim 2, characterized in that at least one pair of communication holes are provided spaced apart in the circumferential direction around the axis.

4. A jig used when assembling the valve device described in claim 3, The regulating portion is inserted into the communication hole and extends in a direction that intersects the axis, The regulating portion is characterized by restricting the displacement of the second member, which is housed in the guide portion, to the other side in the axial direction.

5. The regulating portion is composed of one end and the other end of the overall U-shaped main body. The jig according to claim 4, characterized in that at least one pair of the communication holes are insertable into one end and the other end, respectively.

Images