Valve device

Abstract

The object of the present invention is to provide a valve device that suppresses the outflow of thread fastener to the outside. A pressure regulating valve (1) includes a valve body (10), a valve core (40), and a spring box (61). An external threaded portion (19) and an abutting portion (20) are provided on the outer peripheral surface of the valve body. The spring box includes: an internal threaded portion (64); a tapered portion (66) formed at an open end edge (65) of the internal threaded portion facing one end, which expands in diameter towards one end; and an abutting portion (67) continuously provided with the tapered portion, abutting against the abutting portion when the external threaded portion and the internal threaded portion are threadedly engaged. The external threaded portion and the internal threaded portion are threadedly engaged with each other when at least one of them is coated with thread fastener (80). The maximum value (α) of the inner diameter of the tapered portion is greater than the outer diameter (β) of the external threaded portion. The tapered portion is inclined at an angle of 45° or less relative to the axis (L).

Description

Technical Field

[0001] This invention relates to valve devices. Background Technology

[0002] Previously, valve devices for refrigeration cycles and the like were known (for example, see Patent Document 1). As shown in Figure 5 of Patent Document 1, the temperature expansion valve (valve device) described in Patent Document 1 includes a cylindrical valve housing 10, a valve core 30 for adjusting the opening of a valve port 10c formed on the side wall of the valve housing 10, and a diaphragm device 20 for driving the valve core 30.

[0003] Existing technical documents

[0004] Patent Document 1: Japanese Patent Application Publication No. 2013-36505

[0005] In the temperature expansion valve described in Patent Document 1, such as Patent Document 1... Figure 1 As shown, an external thread 11 is formed on the upper outer peripheral surface of the valve housing 10. An internal thread 21 formed on the inner peripheral surface of the second cylindrical portion 2 of the diaphragm device 20 is threadedly engaged with the external thread 11, thus integrating the valve housing 10 and the diaphragm device 20. In this state, the second sealing surface 22A formed at the front end of the second cylindrical portion 2 engages with the first sealing surface 12A formed at the root of the external thread 11 of the valve housing 10, ensuring a tight seal between the valve housing 10 and the diaphragm device 20.

[0006] However, in the aforementioned temperature expansion valve, the tightening force of the external thread 11 and the internal thread 21 affects the sealing performance between the valve body 10 and the diaphragm device 20. Therefore, to improve the tightening force and sealing performance, a thread-locking agent such as Loctite (registered trademark) is sometimes applied to the threads of the external thread 11 and the internal thread 21. However, if this thread-locking agent flows out from each thread and overflows to the outside via the first sealing surface 12A and the second sealing surface 22A, it is believed that this will affect the appearance, and the overflowing thread-locking agent may adhere to other products, affecting the operation of those products. Summary of the Invention

[0007] The purpose of this invention is to provide a valve device that prevents thread fastener from flowing out to the outside.

[0008] To solve the aforementioned problems and achieve the objective, the valve device of the present invention comprises: a cylindrical main body; a valve core housed inside the main body; and a housing portion housing a control portion for controlling the movement of the valve core and connected to the main body. The valve device is characterized in that: an external thread portion is provided on the outer peripheral surface of the main body, formed along the axis of the main body; and an abutment portion extends radially outward from one end of the external thread portion about the axis; and an internal thread portion is provided in the housing portion, extending from the other end of the external thread portion toward the one end. The external threaded portion is threadedly engaged with the external threaded portion; a tapered portion is formed at the open end edge of the internal threaded portion facing the one end side, and its diameter expands as it faces the one end side; and an abutting portion is continuously provided with the tapered portion, and abuts against the abutting portion when the external threaded portion and the internal threaded portion are threadedly engaged, wherein the external threaded portion and the internal threaded portion are threadedly engaged with each other when at least one of them is coated with thread fastener, the maximum value of the inner diameter of the tapered portion is larger than the outer diameter of the external threaded portion, and the tapered portion is inclined at an angle of 45° or less relative to the axis.

[0009] According to this invention, when the external thread and internal thread are threaded together, the applied threadlocker sometimes generates a force that pushes it towards the contact portion and the portion being contacted. However, in this structure, a tapered portion inclined at an angle of 45° or less relative to the axis of the main body is formed at the open end edge of the internal thread. Therefore, compared with a structure having an open end edge without a tapered portion (i.e., an open end edge extending at an angle of 90° relative to the axis of the main body), the aforementioned pushing force can be reduced by the component force of the tapered portion. Therefore, a valve device that prevents the threadlocker from flowing out can be provided.

[0010] Furthermore, preferably, the length of the tapered portion in the axial direction of the main body is less than one-third of the length of the internal thread portion or the external thread portion in the axial direction. With this structure, the inclination angle of the tapered portion can be maintained, and the thread engagement range of the external thread portion and the internal thread portion can be sufficiently ensured.

[0011] Furthermore, preferably, the abutting portion has a bearing surface facing the abutting portion, and the abutting portion has a metal sealing surface that engages with the bearing surface, thereby maintaining the interior of the housing section as airtight. With this structure, the metal sealing surface of the housing section engages with the bearing surface of the main body, improving the sealing performance between the main body and the housing section, for example, preventing moisture intrusion into the housing section. Furthermore, by utilizing the metal sealing surface to improve airtightness, this invention can also be applied to valve devices, such as mechanical expansion valves for supplying high-pressure fluid flow. That is, by improving airtightness, this structure can also be expected to be used as a pressure vessel.

[0012] Furthermore, preferably, the radially outer end of the aforementioned metal sealing surface is located radially outer relative to the radially outer end of the aforementioned bearing surface. With this structure, the bearing surface can reliably abut against the metal sealing surface from its radially outer end all the way to its radially inner end, thus ensuring sufficient contact area and improving the sealing performance between the bearing surface and the metal sealing surface.

[0013] Furthermore, preferably, a groove is formed on the outer peripheral surface of the main body, between the external threaded portion and the abutting portion, recessed radially inward about the axis. With this structure, even if thread fastener flows from between the external and internal threaded portions toward the abutting portion, the thread fastener can be contained in the groove. Therefore, it is possible to suppress the flow of thread fastener to the abutting portion and the abutting portion.

[0014] The effects of this invention are as follows.

[0015] According to the present invention, a valve device can be provided to prevent thread fastener from flowing out to the outside. Attached Figure Description

[0016] Figure 1 This is a cross-sectional view of the pressure regulating valve according to an embodiment of the present invention, cut along the axial direction of the valve housing.

[0017] Figure 2 This is a cross-sectional view of the valve housing and spring box, showing the initial connection state.

[0018] Figure 3 This is a cross-sectional view showing the valve housing and spring box in the completed connection state.

[0019] Figure 4 (A) is a cross-sectional view of the valve body and spring box in the initial connection state of a pressure regulating valve with the cone angle of the tapered section set to greater than 45°. Figure 4 (B) is a cross-sectional view of the valve body and spring box in the completed connection state of a pressure regulating valve in which the cone angle of the tapered part is set to be greater than 45°.

[0020] In the diagram: α—maximum inner diameter of the tapered part, β—outer diameter of the external threaded part, X—radial, L—axis, 1—pressure regulating valve (valve device), 10—valve housing (main body), 19—external threaded part, 20—abutted part, 40—valve core, 61—spring box (box part), 64—internal threaded part, 65—open end edge, 66—tapered part, 67—abutted part, 69—control part, 80—thread fastener. Detailed Implementation

[0021] The following is based on Figures 1-4Embodiments of the present invention will be described. Furthermore, in the following description, in the figures, the direction along the axis L of the valve housing 10 (main body) of the pressure regulating valve 1 (valve device) will be referred to as "axis L direction". Additionally, one side along axis L will be referred to as "one side L1", and the other side as "the other side L2". Furthermore, the radial direction around axis L will be designated as "radial X", and in radial X, the side closer to axis L will be designated as "radial X inner side", and the side farther from axis L will be designated as "radial X outer side". The direction around axis L will also be referred to as "circumferential direction". However, these definitions of direction are merely for ease of explanation and do not limit the directions in which the pressure regulating valve 1 is manufactured or used.

[0022] In this embodiment, the pressure regulating valve 1, for example, constitutes part of the refrigeration cycle, adjusting the pressure of the refrigerant flowing from the first connector pipe 14 side (primary side) to the second connector pipe 17 side (secondary side), as described later. Figure 1 As shown, the pressure regulating valve 1 includes a valve housing 10 (main body), a valve seat component 30, a valve core 40, a pressure-sensitive unit 50, and an adjusting spring unit 60.

[0023] The valve housing 10 is formed of a metal material such as brass, iron, aluminum, or stainless steel. The valve housing 10 is formed into a bottomed cylindrical shape (cylindrical) by a bottom wall 15 extending radially X and a side wall 12 rising from the bottom wall 15 and extending to the other side L2, the interior of which forms a valve chamber 11. A first port 13a, extending radially X and opening into the valve chamber 11, and a first connector port 13b, continuous with the first port 13a and opening radially X outward, are formed on one side L1 of the side wall 12. The end of the cylindrical first connector tube 14 is fixed to the first connector port 13b in an inserted state. Through this fixing, the interior of the first connector tube 14 communicates with the valve chamber 11 via the first port 13a. A second connector port 16 extending along the axis L is formed on the bottom wall 15. The end of the cylindrical second connector tube 17 is fixed to one side L1 of the second connector port 16 in an inserted state.

[0024] like Figure 2 As shown, an external thread portion 19 is formed on the outer peripheral surface of the sidewall 12. The external thread portion 19 is formed along the axis L at the end of the other side L2 of the sidewall 12. Furthermore, the external thread portion 19 is not limited to being formed at the end of the other side L2 of the sidewall 12, but can also be formed at any location on the outer peripheral surface of the sidewall 12. An abutting portion 20 extending radially outward is formed on the end side (one-end side) of one side L1 of the external thread portion 19. The abutting portion 20 is formed by the portion of the other side L2 of the sidewall 12. The surface of the abutting portion 20 facing the other side L2 constitutes the bearing surface 20a that abuts against the abutting portion 67 of the spring box 61, described later. Furthermore, a groove portion 21 recessed radially inward is formed between the external thread portion 19 and the abutting portion 20.

[0025] And, as Figure 1 As shown, on a portion of the outer peripheral surface of the sidewall 12, on one side L1 of the abutment portion 20, a pair of parallel surfaces 18 spaced apart in the radial direction X are formed. These parallel surfaces 18 are located radially inner relative to the sidewall 12 and extend along the axial direction L. A wrench (not shown) is inserted into the portion where the parallel surfaces 18 are formed. With the valve housing 10 supported by the wrench, the spring box 61 (described later) is connected to the valve housing 10.

[0026] like Figure 1 As shown, the valve housing 10, constructed in this way, houses a valve seat component 30, a valve core 40, and a pressure-sensitive unit 50. First, the valve seat component 30 will be described. The valve seat component 30 has a cylindrical valve seat portion 31 that inserts into the other side L2 portion of the second connector port 16, and a cylindrical guide portion 32 that extends from the valve seat portion 31 to the other side L2. It is formed into a bottomed cylindrical shape using a metal or resin material. A second port 31a extending along the axis L is formed in the center of the valve seat portion 31. A connecting hole 32b extending radially X is formed in the side wall portion 32a of the guide portion 32. Multiple connecting holes 32b are formed at intervals around the axis L in the circumferential direction. According to this structure, the valve chamber 11 communicates with the internal space 33 within the valve seat component 30 via the connecting holes 32b. Furthermore, the internal space 33 communicates with the second connector pipe 17 via the second port 31a.

[0027] Next, the valve core 40 will be described. The valve core 40 is housed within the guide portion 32 of the valve seat component 30 in a manner that allows it to move along the axis L. The valve core 40 is composed of a cylindrical shaft portion 41 extending along the axis L and a needle-shaped portion 42 continuous with one end L1 of the shaft portion 41. The outer peripheral surface of the shaft portion 41 is slidably disposed on the inner peripheral surface of the guide portion 32, thereby guiding the valve core 40 in the axis L direction. A concave portion 41a is formed on the end face of the shaft portion 41 facing the other side L2, recessed towards one side L1. A spherical first ball 43 is provided in the concave portion 41a. A retaining ring 44 extending in the circumferential direction around the axis L is mounted on the outer peripheral surface of the end of the shaft portion 41 on the other side L2.

[0028] A valve spring 45 is provided between the retaining ring 44 and the inner surface 15a of the bottom wall 15 of the valve housing 10. The valve spring 45 is a compression spring that applies force to the valve core 40 toward the other side L2 (i.e., the valve opening side). The needle-shaped portion 42 is formed into a generally conical shape that gradually narrows toward one side L1 (the second port 31a side). The needle-shaped portion 42 is configured to be able to approach and separate from the valve seat 31b relative to the end constituting the other side L2 of the second port 31a in the axial direction L. In this embodiment, it sits on the valve seat 31b in an environment where the valve chamber 11 is at a predetermined pressure or below.

[0029] Next, the pressure-sensitive unit 50 will be described. The pressure-sensitive unit 50 is a component that operates along the axis L according to the pressure in the valve chamber 11. It includes a connecting rod 51 extending along the axis L, a cover 52 disposed on the other side L2 of the connecting rod 51, and a bellows 53 surrounding the connecting rod 51 circumferentially around the axis L. A first recess 51a is formed on the end face of the connecting rod 51 facing the other side L2, recessed towards one side L1. A spherical second ball 54 is disposed in the first recess 51a. A second recess 51b is formed on the end face of the connecting rod 51 facing the other side L1, recessed towards the other side L2. The second recess 51b abuts against the first ball 43 from the other side L2. A first flange 51c protruding radially outward is formed on the outer peripheral surface of the end of the connecting rod 51 on one side L1.

[0030] The cover portion 52 has a large-diameter portion 52a that blocks the opening on the other side L2 of the valve housing 10, and a small-diameter portion 52b that extends from the center of the large-diameter portion 52a to one side L1, and is generally cylindrical in shape. The end of the connecting rod 51 on the other side L2 and the second ball bearing 54 are housed inside the cover portion 52. The outer peripheral surface of the large-diameter portion 52a is welded to the end 12c on the other side L2 of the sidewall 12 of the valve housing 10, thereby providing an airtight connection between the cover portion 52 and the valve housing 10. Through this connection and the construction of the bellows 53 (described later), in this embodiment, fluid in the valve chamber 11 does not enter or exit the spring box 61 (described later). The small-diameter portion 52b has an outer diameter smaller than that of the large-diameter portion 52a and extends along the axis L. A second flange 52c protruding radially outward is formed on the outer peripheral surface of the small-diameter portion 52b. A bellows 53 is disposed between the second flange 52c and the first flange 51c of the connecting rod 51. The bellows 53 is formed as a continuous corrugation with peaks and valleys in the direction of axis L, and is configured to be able to extend and retract in the direction of axis L by elastic force. The elastic force of the bellows 53 exerts a force on the valve core 40 to one side L1 (the valve-closing side).

[0031] The bellows 53 is disposed within the valve chamber 11, so the pressure of the refrigerant flowing within the valve chamber 11 acts as the external pressure on the bellows 53. On the other hand, the internal space of the bellows 53 is connected to the spring box 61 (box section) described later through a small gap between the cover 52 and the other end L2 of the connecting rod 51, and a small gap between the cover 52 and the second ball bearing 54, where a pressure approximately equal to atmospheric pressure acts as the internal pressure. Moreover, the bellows 53 expands and contracts along the axis L according to the pressure difference between the external and internal pressures; the greater the external pressure, the more the bellows contracts and displaces towards the other side L2 (i.e., the valve opening side).

[0032] Next, the adjusting spring unit 60 will be described. The adjusting spring unit 60 includes a spring housing 61 and a control unit 69. The spring housing 61 is formed into a generally bottomed cylindrical shape. A mounting hole 63 extending along the axis L is formed in the center of the bottom 62 of the spring housing 61. An internal thread 64 is formed on the inner circumferential surface of the mounting hole 63 along the axis L. The internal thread 64 is threaded into the external thread 19 of the valve housing 10 from the end of the other side L2 (the other end side) toward the end of the other side L1 (one end side). In addition, when performing this threaded engagement, as Figure 2 , 3 As shown, a thread-fastening agent 80 for improving tightening force is applied to at least one of the external thread portion 19 and the internal thread portion 64.

[0033] Threadlocker 80 may also contain resin-based materials such as Loctite (registered trademark) and adhesives. Furthermore, as... Figure 2 As shown, a tapered portion 66 is formed on the open end edge 65 of the internal thread portion 64 facing one side L1 (one end side). The tapered portion 66 is inclined in such a way that its diameter increases as it faces one side L1 (one end side). Furthermore, an abutment portion 67 facing one side L1 is formed on the bottom 62 of the spring box 61. The abutment portion 67 is continuous with the end of one side L1 of the tapered portion 66 and extends radially outward.

[0034] When the external thread 19 and internal thread 64 are threaded together, the abutting portion 67 abuts against the bearing surface 20a of the abutted portion 20 formed on the valve housing 10. The radially outer end 67a of the abutting portion 67 is located radially outer relative to the radially outer end 20b of the bearing surface 20a, thereby allowing approximately the entire portion of the bearing surface 20a to abut against the abutting portion 67. Through the abutting of the abutting portion 67 against the bearing surface 20a, a seal is formed between the spring box 61 and the valve housing 10. Furthermore, the abutting portion 67 can also be a metal sealing surface that bites into the bearing surface 20a. Moreover, the sealing performance between the abutting portion 67 and the bearing surface 20a can be appropriately set.

[0035] For example, to prevent corrosion of the adjusting spring 72 (described later) located inside the spring box 61, and from the viewpoint of improving the anti-drip properties inside the spring box 61, the abutment portion 67 (metal sealing surface) and the bearing surface 20a can also be in watertight contact. In this case, the interior of the spring box 61 is watertightly maintained by the abutment portion 67 (metal sealing surface), the aforementioned cover portion 52, and the bellows 53. Furthermore, for example, when the present invention is used in a mechanical expansion valve or the like corresponding to a high-pressure refrigerant, the abutment portion 67 and the bearing surface 20a can also be in airtight contact. In this case, the valve chamber 11 can be connected to the interior of the spring box 61, serving as a pressure vessel to make the interior of the spring box 61 airtight. Furthermore, as... Figure 1As shown, an internal thread 68 is formed on the inner circumferential surface of the L2 portion on the other side of the spring box 61. The external thread 71a of the adjusting screw 71, described later, is threaded into the internal thread 68.

[0036] like Figure 2 As shown, the maximum value α of the inner diameter of the portion forming the tapered portion 66 on the inner circumferential surface of the mounting hole 63 is set to be larger than the outer diameter β of the external thread portion 19. Furthermore, in Figure 3 In the cross-sectional view shown, the tapered portion 66 is inclined at an angle θ of 45° or less relative to an imaginary line L3 parallel to the axis L of the valve housing 10. That is, the tapered portion 66 is inclined at an angle θ of 45° or less relative to the axis L. Furthermore, the angle θ is more preferably 40° or less. Additionally, the length B of the tapered portion 66 in the axis L direction is preferably set to one-third or less of the length A of the internal thread portion 64 in the axis L direction. However, while this embodiment sets the length B of the tapered portion 66 in the axis L direction to one-third or less of the length A of the internal thread portion 64, the length B of the tapered portion 66 in the axis L direction may also be set to one-third or less of the length of the external thread portion 19 in the axis L direction.

[0037] Here, when the external thread 19 of the valve housing 10 and the internal thread 64 of the spring box 61 are threaded together, as follows: Figure 2 As shown, sometimes the applied threadlocker 80 generates a force P that pushes it toward the abutting portion 20 and the abutting portion 67. In this case, as... Figure 4 As shown in (B), in the spring box 200 different from this embodiment, if the inclination angle of the tapered portion 203 formed on the opening edge 202 of the internal thread portion 201 is an angle θ2 greater than 45° relative to the imaginary line L4 parallel to the axis L of the valve housing 300, then Figure 4 (A) The pushing force P tends to increase. That is, if the tilt angle of the tapered portion 203 relative to the axis L is greater than 45°, the pushing force P tends to increase. This is particularly noticeable when the tapered portion 203 extends at 90° (i.e., radial X) relative to the axis L. As a result, the thread-locking agent 80 sometimes flows out toward the abutted portion 302 of the valve housing 300 and the abutted portion 204 of the spring box 200.

[0038] Furthermore, if the leaked threadlocker 80 has properties that make it difficult to cure, it may sometimes overflow to the outside through the space between the mating part 302 and the abutting part 204. Therefore, considerations are given to its potential impact on the appearance of the pressure regulating valve 1, and the impact of the overflowing threadlocker 80 adhering to other products, affecting their operation. Additionally, consideration is also given to the potential impact of the threadlocker 80 adhering to the mating part 302 and the abutting part 204 on the airtightness of the spring box 61.

[0039] However, in this structure, since a tapered portion 66 inclined at an angle of 45° or less relative to the axis L is formed at the opening edge 65 of the internal thread portion 64, the aforementioned pushing force P can be reduced by the component force of the tapered portion 66. Specifically, as a component of the force acting on the thread fastener 80, for example, in the case of a radial force acting on the external thread portion 19 and the internal thread portion 64, and a force acting from the tapered portion 66 toward the abutting portion 20, the following applies: That is, when the aforementioned angle of the tapered portion 66 is greater than 45°, the force acting from the tapered portion 66 toward the abutting portion 20 tends to be larger than the force acting on the radial force of the external thread portion 19 and the internal thread portion 64. In contrast, when the aforementioned angle is 45°, the radial force acting on the external thread portion 19 and the internal thread portion 64 is approximately the same as the force acting from the tapered portion 66 toward the abutting portion 20. Furthermore, if the aforementioned angle is less than 45°, the force acting from the tapered portion 66 toward the abutted portion 20 is more likely to be smaller compared to the radial force acting on the external thread portion 19 and the internal thread portion 64. This structure suppresses the outflow of thread fastener 80. Therefore, the impact of the thread fastener 80 overflowing to the outside on the appearance and other components can be reduced. Additionally, according to this structure, the flow of thread fastener 80 and its adhesion to the bearing surface 20a of the abutted portion 20 and the abutted portion 67 (metal sealing surface) itself can be suppressed, thus reducing the impact on the aforementioned airtightness. Moreover, in this structure, by providing a groove 21 between the external thread portion 19 and the abutted portion 20 relative to the outer peripheral surface of the sidewall 12, the outflowing thread fastener 80 can be contained in the groove 21. Therefore, the flow of thread fastener 80 to the abutted portion 20 and the abutted portion 67 can be further suppressed.

[0040] Next, refer to Figure 1 The control unit 69 will be described below. The control unit 69 is housed within the spring housing 61 and adjusts the pressure of the valve core 40 when it leaves the valve seat 31b. That is, the control unit 69 controls the operation of the valve core 40. The control unit 69 includes a spring seat 70, an adjusting screw 71, and an adjusting spring 72. The spring seat 70 is formed in a generally cylindrical shape and is disposed within the spring housing 61 on one side L1. A recess 70a is formed on the surface of the spring seat 70 facing one side L1, recessed towards the other side L2, and the recess 70a abuts against the second ball 54 from the other side L2. The adjusting screw 71 is formed in a bottomed cylindrical shape with the other side L2 portion as its base and is disposed within the spring housing 61 on the other side L2 portion. An external thread 71a is formed on the outer peripheral surface of the adjusting screw 71. The external thread 71a is threadedly engaged with the internal thread 68 of the spring housing 61.

[0041] An adjusting spring 72 is positioned between the spring seat 70 and the adjusting screw 71. The adjusting spring 72 is a compression spring that applies force to the valve core 40 towards one side L1 via the spring seat 70, the second ball 54, the connecting rod 51, and the first ball 43. Furthermore, the force of the adjusting spring 72 can be changed by adjusting the rotation of the adjusting screw 71, causing the adjusting screw 71 to move towards one side L1 or the other side L2, thus changing the compression force of the adjusting spring 72. In this structure, the bellows 53 (pressure-sensitive unit 50) and the adjusting spring 72 (adjusting spring unit 60) exert a force on the valve core 40 towards one side L1 (closed valve side). On the other hand, the valve spring 45 exerts a force on the valve core 40 towards the other side L2 (open valve side).

[0042] Next, the operation of pressure regulating valve 1 will be explained. First, as... Figure 1 As shown, with the valve core 40 seated in the valve seat 31b, refrigerant flows into the valve chamber 11 from the first connector pipe 14 side (primary side) via the first port 13a. This inflow causes the pressure inside the valve chamber 11 to rise. Furthermore, this pressure increase causes the pressure outside the bellows 53 to increase, causing the bellows 53 to contract and displace towards the other side L2. This displacement increases the force exerted by the adjusting spring 72 and the bellows 53 on the valve core 40 towards one side L1 according to their respective elastic coefficients. On the other hand, if the pressure inside the valve chamber 11 continues to rise, the compressive load acting on the other side L2 relative to the bellows 53 increases. Consequently, when the force exerted by the adjusting spring 72 and the bellows 53 towards one side L1 is less than the resultant force of the force exerted by the valve spring 45 towards the other side L2 and the compressive load, the valve core 40 dismounts towards the other side L2. As a result, the refrigerant at the predetermined pressure flows out into the second connector pipe 17 through the valve chamber 11, the connecting hole 32b of the valve seat component 30, the internal space 33, and the second port 31a.

[0043] Next, when the refrigerant pressure in valve chamber 11 decreases, the pressure outside the bellows 53 decreases, and the bellows 53 extends and shifts to one side L1. This displacement reduces the force exerted by the adjusting spring 72 and the bellows 53 on the valve core 40 towards one side L1 according to their respective elastic coefficients. On the other hand, if the pressure in valve chamber 11 continues to decrease, the compressive load acting on the other side L2 relative to the bellows 53 decreases. Furthermore, when the force exerted towards one side L1 by the adjusting spring 72 and the bellows 53 exceeds the resultant force of the force exerted towards the other side L2 by the valve spring 45 and the compressive load, the valve core 40 settles towards one side L1. In this way, the pressure regulating valve 1 adjusts the pressure of the refrigerant flowing inside.

[0044] According to the above-described embodiment, when the external thread portion 19 and the internal thread portion 64 are threaded together, a force P sometimes pushes the applied threadlocker 80 toward the abutting portion 20 and the abutting portion 67. However, in this structure, a tapered portion 66 inclined at an angle of 45° or less relative to the axis L is formed at the open end edge 65 of the internal thread portion 64. Therefore, compared with a structure having an open end edge without a tapered portion 66 (i.e., an open end edge extending at an angle of, for example, 90° relative to the axis L), the force of the tapered portion 66 can reduce the aforementioned pushing force P. Therefore, a pressure regulating valve 1 (valve device) that inhibits the outflow of threadlocker 80 can be provided.

[0045] Furthermore, according to the above embodiment, the length B of the tapered portion 66 in the axis L direction is set to be less than one-third of the length A of the internal thread portion 64 or the external thread portion 19 in the axis L direction. Therefore, the tilt angle of the tapered portion 66 can be maintained, and the thread engagement range of the external thread portion 19 and the internal thread portion 64 can be sufficiently ensured.

[0046] Furthermore, according to the above embodiment, by having the abutment portion 67 (metal sealing surface) of the spring box 61 (box portion) engage with the bearing surface 20a of the valve housing 10 (main body portion), the sealing performance between the valve housing 10 and the spring box 61 is improved. For example, moisture intrusion into the spring box 61 can be suppressed. Moreover, by utilizing the abutment portion 67 (metal sealing surface) to improve airtightness, the present invention can also be applied to valve devices such as mechanical expansion valves that supply high-pressure fluid flow. That is, by improving airtightness, this structure can also be expected to be used as a pressure vessel.

[0047] Furthermore, according to the above embodiment, the radially outer end 67a of the abutment portion 67 is located radially outer relative to the radially outer end 20b of the bearing surface 20a. Therefore, the bearing surface 20a can reliably abut against the abutment portion 67 from the radially outer end 20b all the way to the radially inner side, thus ensuring sufficient contact area between them and improving the sealing performance between the bearing surface 20a and the abutment portion 67.

[0048] Furthermore, according to the above embodiment, a groove 21 is formed on the outer peripheral surface of the sidewall 12 between the external thread portion 19 and the abutting portion 20. Therefore, even if the thread fastener 80 flows from between the external thread portion 19 and the internal thread portion 64 toward the abutting portion 20 and the abutting portion 67, the thread fastener 80 can be contained in the groove 21. Thus, the flow of the thread fastener 80 between the abutting portion 20 and the abutting portion 67 can be suppressed.

[0049] Furthermore, the embodiments described above merely illustrate representative aspects of the present invention, and the present invention is not limited thereto. For example, the valve device has been described as a pressure regulating valve 1, but as mentioned above, the valve device may also be a mechanical expansion valve. In addition, in this embodiment, the spring box 61 is configured to be airtight inside by means of the abutment portion 67, the cover portion 52, and the bellows 53, which are made of metal sealing surfaces, so that fluid does not enter or exit between the valve chamber 11 and the spring box 61. However, this is not a limitation, and the valve chamber 11 and the spring box 61 may also communicate with each other.

Claims

1. A valve device comprising: Tubular main body; The valve core is housed inside the aforementioned main body; and The housing section houses the control unit that controls the movement of the valve core and is connected to the main body section. The valve device is characterized by, The outer peripheral surface of the main body is provided with: an external thread portion formed along the axis of the main body; and an abutment portion extending radially outward from one end of the external thread portion around the axis. The aforementioned housing portion includes: an internal thread portion that is threadedly engaged with the external thread portion from the other end toward the aforementioned end; a tapered portion formed at the open end edge of the internal thread portion toward the aforementioned end, which expands in diameter toward the aforementioned end; and an abutting portion that is continuously provided with the tapered portion and abuts against the abutting portion when the external thread portion and the internal thread portion are threadedly engaged. The aforementioned external thread portion and the aforementioned internal thread portion are threaded together with at least one of them having been coated with thread-locking agent. The maximum value of the inner diameter of the aforementioned tapered portion is larger than the outer diameter of the aforementioned externally threaded portion. The aforementioned tapered portion is inclined at an angle of less than 45° relative to the aforementioned axis.

2. The valve device according to claim 1, characterized in that, The length of the tapered portion in the axial direction of the main body is less than one-third of the length of the internal thread portion or the external thread portion in the axial direction.

3. The valve device according to claim 1, characterized in that, The aforementioned abutting portion is provided with a bearing surface facing the abutting portion side. The aforementioned abutment portion is provided with a metal sealing surface that bites into the aforementioned bearing surface. The interior of the aforementioned box is kept airtight by the aforementioned metal sealing surface.

4. The valve device according to claim 3, characterized in that, The radially outer end of the aforementioned metal sealing surface is located radially outer relative to the radially outer end of the aforementioned bearing surface.

5. The valve device according to claim 1, characterized in that, On the outer peripheral surface of the main body, a groove is formed between the external threaded portion and the abutted portion, which is recessed radially inward about the axis.

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