Slide-type switching valve and refrigeration cycle system

Abstract

To provide a slide-type selector valve and a refrigerating cycle system capable of improving durability against collision load when a piston contacts a stopper part of a lid member.SOLUTION: A lid member 12 in a valve housing of a slide-type selector valve includes: a lid body part 121; a stopper part 122 which protrudes from the lid body part 121 in a flange-like manner, and contacts and receives a piston 221 of a slide mechanism 22; and impact stress relaxing means relaxing stress caused by impact when the piston 221 contacts the stopper part 122. The impact stress relaxing means is provided with an impact stress relaxing part 123 which cylindrically protrudes in an axial direction from an outer peripheral edge 122b of the stopper part 122 between the stopper part 122 and an opening end 11b of a valve body 11, has a protrusion end edge 123a abutted to the opening end 11b of the valve body 11, and is fixed to the opening end 11b.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a slide-type switching valve that is used in a refrigeration cycle system such as an air conditioner and switches refrigerant flow paths, and to a refrigeration cycle system.

Background Art

[0002] Conventionally, there has been known a slide-type switching valve in which a valve body is housed inside a valve housing in which openings at both ends of a cylindrical valve main body are each closed by a lid member (see, for example, Patent Document 1). In the slide-type switching valve described in Patent Document 1, the valve element is coupled to a slide mechanism that receives slide driving force via a piston and moves inside the valve housing, and the valve element moves together with the slide mechanism. In this slide-type switching valve, the lid member includes a lidded cylindrical lid main body portion, and a flange-shaped portion that projects in a flange shape and has a portion near an outer peripheral edge fixed to an open end of the valve main body. A portion of the flange-shaped portion of the lid member near an inner periphery projects toward the inside of the valve main body, and the projecting surface portion serves as a stopper portion against which the piston of the slide mechanism moving together with the valve element abuts and is received.

Prior Art Literature

Patent Literature

[0003]

Patent Document 1

Summary of the Invention

Problem to be Solved by the Invention

[0004] In the aforementioned sliding type switching valve, when the piston contacts the stopper, the impact load at the time of contact is transmitted to the fixing portion between the open end of the valve body and the flange-shaped portion of the cover member, generating a stress that attempts to peel the flange-shaped portion of the cover member away from the open end of the valve body in the axial direction. In recent years, ultra-high-pressure fluids such as CO2 are sometimes used as the fluid in refrigeration cycle systems that provide sliding driving force to the piston, and in this case, the impact load when the piston contacts the stopper may become excessive. Therefore, there is a need to improve durability against such excessive impact loads.

[0005] The object of the present invention is to provide a sliding type switching valve and a refrigeration cycle system that can improve the durability of the lid member against impact loads when the piston contacts the stopper portion. [Means for solving the problem]

[0006] The present invention provides a sliding type switching valve comprising: a valve housing having a cylindrical shape with at least one pair of pipes connected to its circumferential wall, the openings at both ends of the valve body closed by cover members; a valve element installed inside the valve body so as to be slidable in the axial direction of the valve body for switching the communication state of the pipes; and a sliding mechanism having a mechanism portion extending in the axial direction inside the valve body and having pistons at both ends, the valve element being connected to the intermediate portion thereof, and the pistons providing an axial sliding driving force for sliding the valve element, wherein the cover member is formed in the shape of a covered cylinder with an inner diameter smaller than the inner diameter of the opening of the valve body, and the cylindrical opening is the same as the opening of the valve body The valve body comprises: a lid body portion positioned outside the opening of the valve body in the axial direction so as to face the opening; a stopper portion extending in a flange shape from the opening edge of the cylindrical opening of the lid body portion toward the outside of the lid body portion, having an outer diameter larger than the inner diameter of the opening of the valve body, and contacting and receiving the piston at one end of the slide mechanism that has slid through the opening in the axial direction, with the surface facing the opening side; and an impact stress relief means for relieving the stress caused by the impact when the piston contacts the stopper portion, wherein the impact stress relief means is provided between the stopper portion and the opening end surrounding the opening of the valve body, from the outer peripheral edge of the stopper portion across the aforementioned open end The aforementioned cylindrical protrusion in the axial direction, The inner surface of the cylindrical shape is formed flat, and in the cylindrical shape The means for relieving the stress is characterized by the provision of an impact stress relief portion, the protruding edge of which abuts against the open end of the valve body and is fixed to the open end. In addition to the provision of the impact stress relief portion, the impact stress relief means may also be a means for relieving the stress by the stopper portion bending and deforming in the axial direction due to the impact when the stopper portion abuts against the piston, and the impact stress relief portion bending and deforming in a direction intersecting the axial direction.

[0007] In this sliding type switching valve, the lid member is provided with an impact stress relief means between the stopper portion, which the piston of the sliding mechanism abuts against, and the protruding edge fixed to the open end of the valve body, to alleviate the stress generated at the fixed portion between the valve body and the lid member due to the impact when the piston abuts against it. With this impact stress relief means, the stopper portion is positioned away from the fixed portion between the valve body and the lid member in the axial direction of the valve body by the placement of the impact stress relief portion between the stopper portion and the open end of the valve body. As a result, even when a large impact load occurs when an ultra-high pressure fluid is used in the refrigeration cycle system and the piston abuts against the stopper portion, the stress acting on the fixed portion between the valve body and the lid member is alleviated. In other words, the impact load at the time of abutment is less likely to directly act as a stress that tries to separate the open end of the valve body and the fixed portion between the lid member, thereby improving the durability of the lid member against the impact load when the piston abuts against the stopper portion. Furthermore, by providing an impact stress relief mechanism in which the stopper portion deforms axially and the impact stress relief portion deforms in a cross direction, the direct impact of the collision load on the fixed portion during contact can be further suppressed. This further improves durability against collision loads.

[0008] Here, the cylindrical impact stress relief portion has an axial length L and a wall thickness T, 0.5T ≤ L It is preferable that the structure be such that it satisfies the following relationship.

[0009] With this configuration, by making the axial length of the impact stress relief section sufficiently long and positioning the stopper section at a position sufficiently far outward from the fixing portion between the valve body and the cover member in the axial direction of the valve body, the stress at the fixing portion between the valve body and the cover member can be relieved more effectively.

[0010] Furthermore, the impact stress relief section is further, L≦5T It is even more preferable that the structure be formed to satisfy the following relationship.

[0011] This configuration allows for effective stress relief while keeping the size of the cover member, including the impact stress relief section, and thus the sliding type switching valve, down.

[0012] Furthermore, it is preferable that the impact stress relief portion is provided with a small-diameter cylindrical projection that protrudes in a cylindrical shape with a smaller diameter than the outer diameter of the impact stress relief portion from a position closer to the inner circumference of the protruding edge toward the opening side of the valve body in the axial direction, or a small-diameter recess that is recessed to a smaller diameter than the outer diameter of the impact stress relief portion from a position closer to the inner circumference of the protruding edge toward the stopper portion in the axial direction, and the opening end of the valve body is provided with a positioning recess at a position closer to the inner circumference of the opening end into which the small-diameter cylindrical projection of the impact stress relief portion is fitted to position the cover member when it is attached, or a positioning protrusion at a position closer to the inner circumference of the opening end into which the small-diameter recess of the impact stress relief portion is fitted to position the cover member when it is attached.

[0013] With this configuration, the lid member is positioned relative to the opening of the valve body by fitting the small-diameter cylindrical projection into the positioning recess, or by fitting the positioning protrusion into the small-diameter recess, allowing the subsequent fixing work to be performed with good workability.

[0014] Also, The valve body and the cover member The fixed portion is a welded portion formed by welding the protruding edge to the opening end of the valve body from the outer circumferential surface side of the valve body, and is more preferably formed with a welding depth that does not penetrate the small diameter cylindrical projection or the positioning projection in the thickness direction.

[0015] With this configuration, the welded portion, which serves as the fixed part, is formed with a welding depth that does not penetrate in the thickness direction through the small-diameter cylindrical projection on the lid member or the positioning projection on the valve body, thereby effectively preventing spatter from entering the inside of the valve body during welding.

[0016] Further, the refrigeration cycle system of the present invention is characterized by comprising: a compressor that compresses a refrigerant that is a fluid; a first heat exchanger that functions as a condenser in a cooling mode; a second heat exchanger that functions as an evaporator in the cooling mode; an expansion means that expands and depressurizes the refrigerant between the first heat exchanger and the second heat exchanger; and the slide type switching valve described above.

[0017] According to this refrigeration cycle system, since it includes the slide type switching valve described above, it is possible to improve the durability against the collision load generated when the piston abuts against the stopper portion of the cover member.

Effects of the Invention

[0018] According to the slide type switching valve and the refrigeration cycle system of the present invention, it is possible to improve the durability against the collision load generated when the piston abuts against the stopper portion of the cover member.

Brief Description of Drawings

[0019] [Figure 1] It is a cross-sectional view showing a cross-section along the axial direction of a valve housing of the slide type switching valve according to one embodiment. [Figure 2] It is an enlarged cross-sectional view of the cover member shown in Fig. 1. [Figure 3] It is a view showing an end structure on the right side in the drawing of the slide type switching valve shown in Fig. 1, in a state where the piston abuts against the stopper portion of the cover member. [Figure 4] It is an enlarged view showing an area A11 in Fig. 3. [Figure 5] It is a schematic diagram showing a refrigeration cycle system including the slide type switching valve shown in Figs. 1 to 4. [Figure 6] It is a graph showing, for various cylinder wall thicknesses T, the change in the stress relaxation effect when the axial length L is changed with respect to the cylinder wall thickness T, for the impact stress relaxation portion shown in Fig. 4. [Figure 7]This drawing is an enlarged sectional view similar to FIG. 4, showing first to third modified examples of the impact stress relaxation portion shown in FIG. 4 for which a stress relaxation effect is expected from the graph shown in FIG. 6. [Figure 8] This drawing is an enlarged sectional view similar to FIG. 4, showing fourth to sixth modified examples of the impact stress relaxation portion shown in FIG. 4 for which a stress relaxation effect is expected from the graph shown in FIG. 6. MODE FOR CARRYING OUT THE INVENTION

[0020] Hereinafter, a slide type switching valve and a refrigeration cycle system according to an embodiment of the present invention will be described with reference to FIGS. 1 to 5.

[0021] FIG. 1 is a cross-sectional view showing a cross-section along the axial direction of a valve housing of the slide type switching valve according to one embodiment. FIG. 2 is an enlarged cross-sectional view showing the cover member shown in FIG. 1. FIG. 3 is a view showing the end structure on the right side in the drawing of the slide type switching valve shown in FIG. 1, in a state where a piston is in contact with a stopper portion of the cover member, and FIG. 4 is an enlarged view showing a region A11 in FIG. 3. FIG. 5 is a schematic diagram showing a refrigeration cycle system including the slide type switching valve shown in FIGS. 1 to 4. In the following description, in FIGS. 1 and 5, the side where the E joint pipe 13e is illustrated is referred to as the left side, and the side where the C joint pipe 13c is illustrated is referred to as the right side.

[0022] As shown in FIG. 1, the slide type switching valve 10 of the present embodiment is a four-way switching valve that switches the communication state of four pipes, and has a structure in which a slide valve body 2 is provided inside a valve housing 1.

[0023] The valve housing 1 is a cylindrical member with both ends closed, and is composed of a cylindrical valve body 11 and two cover members 12. The cover members 12 are attached to the valve body 11 so as to close the openings 11a at each end of the valve body 11. In this embodiment, the cover members 12 are fixed to the valve body 11 by welding from the outer circumferential surface side of the valve body 11. Figure 2 shows the cover member 12 in its individual state before welding, and Figure 3 shows the state in which the cover members 12 have been welded to the valve body 11, along with a part of the piston 221 in the slide valve body 2.

[0024] The valve body 11 and the cover member 12 are made of metal such as stainless steel or brass. Methods for fixing such metal members together include welding and brazing. When welding is used, as in this embodiment, it is preferable that the valve body 11 and cover member 12, which are the objects to be fixed, be made of stainless steel. Furthermore, the central axis of the valve body 11 and cover member 12 is the axis X of the valve housing 1. Four pipes, D-connector pipe 13d, E-connector pipe 13e, S-connector pipe 13s, and C-connector pipe 13c (details of which will be described later), are connected to the circumferential wall of the valve housing 1 so as to communicate with the inside of the valve housing 1.

[0025] A valve seat 15 is provided on the inner circumferential surface of the valve body 11, against which the valve element 21 slides. This valve seat 15 is located in the middle section of the valve body 11, and a D-type fitting pipe 13d, which serves as high-pressure piping and opens into the valve body 11, is attached to the valve seat 15 at a position opposite to the valve seat 15 in the middle section of the valve body 11. In addition, a pair of E-type fitting pipes 13e and C-type fitting pipes 13c, which serve as conduits, and an S-type fitting pipe 13s, which serves as low-pressure piping, are attached to the valve seat 15, aligned in a straight line in the axial direction X of the valve housing 1.

[0026] The slide valve body 2 is installed inside the valve body 11 so as to be slidable in the axial direction D11 of the valve body 11, and is a component that switches the communication state of the four pipes mentioned above. This slide valve body 2 comprises a valve body 21 and a slide mechanism 22.

[0027] The valve body 21 switches the communication state of the four pipes mentioned above by sliding in the axial direction D11. The valve body 21 has a bowl-shaped recess 21A formed on its inside. At the left end position in Figure 1, the valve body 21 connects the S joint pipe 13s and the E joint pipe 13e through the bowl-shaped recess 21A. At this time, the C joint pipe 13c communicates with the D joint pipe 13d mainly through the through hole 222a of the connecting plate 222 of the slide mechanism 22 within the high-pressure chamber 1A partitioned by the pistons 221 at both ends of the slide mechanism 22 inside the valve housing 1. Furthermore, at the right end position in Figure 1 when the slide valve body 2 has moved to the right, the valve body 21 connects the S joint pipe 13s and the C joint pipe 13c through the bowl-shaped recess 21A. At this time, the E joint pipe 13e is in communication with the D joint pipe 13d within the high-pressure chamber 1A, mainly via the through hole 222a.

[0028] The slide mechanism 22 is a mechanism located inside the valve body 11, extending in the axial direction D11 and having pistons 221 at both ends. The valve body 21 is connected to the middle of the slide mechanism 22, and the pistons 221 provide a sliding driving force in the axial direction D11, causing the valve body 21 to slide. This slide mechanism 22 comprises a pair of pistons 221 and a connecting plate 222. Each of the pair of pistons 221 is generally disc-shaped and is positioned to sandwich the valve body 21 in the axial direction D11. The connecting plate 222 is a plate member extending in the axial direction D11, to which the valve body 21 is connected in the middle so that it can slide on the valve seat 15, with pistons 221 fixed at both ends. In addition, the connecting plate 222 has one of the above-mentioned through holes 222a at a position midway between the valve body 21 and each piston 221.

[0029] The inside of the valve housing 1 is divided by pistons 221 at both ends of the slide mechanism 22 into a central high-pressure chamber 1A and a first operating chamber 1B and a second operating chamber 1C located on either side of the high-pressure chamber 1A. Driving fluid flows from the pilot valve 3 shown in Figure 5 into the first operating chamber 1B and the second operating chamber 1C, and the pistons 221 at each end receive sliding driving force through this driving fluid.

[0030] In the refrigeration cycle system 30 shown in Figure 5, the D joint pipe 13d is a high-pressure pipe connected to the discharge port of the compressor 31, and the S joint pipe 13s is a low-pressure pipe connected to the suction port of the compressor 31. The C joint pipe 13c is a conduit connected to the outdoor heat exchanger 32 (first heat exchanger), and the E joint pipe 13e is a conduit connected to the indoor heat exchanger 33 (second heat exchanger). The outdoor heat exchanger 32 and the indoor heat exchanger 33 are connected via a throttling device 34 (expansion means). The refrigeration cycle system 30 is composed of a path from the C joint pipe 13c to the outdoor heat exchanger 32, throttling device 34, indoor heat exchanger 33 and E joint pipe 13e, and a path from the S joint pipe 13s to the compressor 31 and D joint pipe 13d. Note that the refrigerant in the refrigeration cycle system 30 contains a small amount of refrigerant oil to protect the compressor 31 and other equipment.

[0031] The pilot valve 3 shown in Figure 5 moves the slide valve body 2 in the axial direction D11 by circulating drive fluid through a pair of spaces inside the valve housing 1 that sandwich the slide valve body 2 in the axial direction D11, namely the first working chamber 1B and the second working chamber 1C. In this embodiment, the pilot valve 3 moves the slide valve body 2 by circulating fluid from the D joint pipe 13d, which is a high-pressure pipe, through one of the first working chamber 1B and the second working chamber 1C, and fluid from the S joint pipe 13s, which is a low-pressure pipe, through the other.

[0032] The pilot valve 3 has a similar structure to the slide-type switching valve 10, and switches the flow path by sliding the pilot valve body inside the pilot valve housing. The pilot valve body switches the destination of the thin tube 14s for the low-pressure joint, which communicates with the S-joint pipe 13s, a low-pressure pipe connected to the intake port of the compressor 31, as follows: That is, the pilot valve body switches the destination of the thin tube 14s for the low-pressure joint between the thin tube 14L for the first housing, which is connected to the first working chamber 1B of the slide-type switching valve 10, and the thin tube 14R for the second housing, which is connected to the second working chamber 1C. At the same time, the pilot valve body switches the destination of the thin tube 14d for the high-pressure joint, which communicates with the D-joint pipe 13d, a high-pressure pipe connected to the discharge port of the compressor 31, between the thin tube 14R for the second housing and the thin tube 14L for the first housing. This creates a pressure difference between the pressure in the first working chamber 1B, where the suction and discharge pressures of the compressor 31 are introduced, and the pressure in the second working chamber 1C. This pressure difference acting on the pair of pistons 221 causes the slide valve body 2 to slide from the high-pressure side to the low-pressure side in the axial direction D11. This sliding movement switches the position of the valve body 21 in the slide valve body 2, thereby switching the flow path of the refrigeration cycle system 30.

[0033] With the above configuration, the high-pressure refrigerant compressed by the compressor 31 flows into the high-pressure chamber 1A from the D joint pipe 13d. In cooling operation (cooling mode), the high-pressure refrigerant flows into the outdoor heat exchanger 32 from the C joint pipe 13c. In heating operation (heating mode) with the valve body 21 switched, the high-pressure refrigerant flows into the indoor heat exchanger 33 from the E joint pipe 13e. That is, during cooling operation, as shown by the solid arrows, the refrigerant discharged from the compressor 31 circulates through the C joint pipe 13c → outdoor heat exchanger 32 → throttling device 34 → indoor heat exchanger 33 → E joint pipe 13e. In this circulation, the outdoor heat exchanger 32 functions as a condenser and the indoor heat exchanger 33 functions as an evaporator, providing cooling. The throttling device 34 expands and reduces the pressure of the refrigerant between the outdoor heat exchanger 32 and the indoor heat exchanger 33. Furthermore, during heating operation, as indicated by the dotted arrows, the refrigerant is circulated in the reverse direction, with the indoor heat exchanger 33 functioning as a condenser and the outdoor heat exchanger 32 as an evaporator, thereby providing heating.

[0034] In this embodiment, the pair of lid members 12 have the following configuration. The pair of lid members 12 have a mirror-symmetric structure as shown in Figure 1, and in the following description, the right-hand lid member 12, shown in enlarged view in Figures 2 and 3, will be used as a representative example.

[0035] The lid member 12 is a covered cylindrical member comprising a lid body portion 121, a stopper portion 122, and an impact stress relief portion 123. The lid body portion 121 is a dome-shaped covered cylindrical portion having an inner diameter φ12 that is smaller than the inner diameter φ11 of the opening 11a of the valve body 11. This lid body portion 121 is positioned axially D11 outward from the opening 11a of the valve body 11 such that its cylindrical opening 121a faces the opening 11a of the valve body 11. Mounting holes 121c for the first housing tube 14L and the second housing tube 14R are formed in the peripheral wall of this lid body portion 121.

[0036] The stopper portion 122 is a flange-like projection extending outward from the opening edge 121b of the cylindrical opening 121a of the lid body portion 121, having an outer diameter φ13 that is larger than the inner diameter φ11 of the opening 11a of the valve body 11. In this embodiment, the outer diameter φ13 of the stopper portion 122 is approximately the same as the outer diameter φ14 of the valve body 11. The stopper surface 122a of this stopper portion 122 is the surface facing the opening 11a side of the valve body 11, and the piston 221 at one end of the slide mechanism 22, which has slid through the opening 11a in the axial direction D11, comes into contact with the stopper surface 122a, restricting the movement of the slide valve body 2 to the right and left in the axial direction D11.

[0037] The impact stress relief portion 123 protrudes cylindrically from the outer peripheral edge 122b of the stopper portion 122 in the axial direction D11, and its protruding end edge 123a abuts against the opening end 11b surrounding the opening 11a of the valve body 11 and is fixed to the opening end 11b. As described above, this fixing is done by welding. In this embodiment, the stress caused by the impact when the piston 221 contacts the stopper portion 122 is relieved by impact stress relief means having two aspects, as described below: means of relieving stress by the arrangement of the impact stress relief portion 123, and means of relieving stress by the deflection deformation of the stopper portion 122 and the impact stress relief portion 123.

[0038] <Regarding impact stress relief measures> As described above, in conventional sliding type switching valves, when the piston contacts the stopper, the impact load at the time of contact is transmitted to the fixing portion between the open end of the valve body and the flange-shaped portion of the cover member, generating stress that attempts to peel the flange-shaped portion of the cover member away from the open end of the valve body in the axial direction. This may reduce the durability against the impact load when the piston contacts the stopper.

[0039] In contrast, in this embodiment, by employing an impact stress relief means in the lid member 12 that relieves the stress caused by the impact when the piston 221 contacts the stopper portion 122, the conventional problem (stress is generated when the piston contacts the stopper portion, attempting to peel the flange-shaped portion of the lid member away from the fixed portion between the valve body and the lid member) is resolved, and the durability against impact load when the piston 221 contacts the stopper portion 122 can be improved. Herein, the impact stress relief means in this embodiment has an impact stress relief means (1) (arrangement of the impact stress relief portion) and an impact stress relief means (2) (flexural deformation) as described above, so they will be described in order below.

[0040] <Impact stress relief means (1) (Arrangement of impact stress relief section)> The impact stress relief means (1) (arrangement of the impact stress relief part) is a means of providing an impact stress relief part 123 between the stopper part 122 and the open end 11b of the valve body 11, as shown in Figure 3. The impact stress relief part 123 protrudes axially D11 from the outer peripheral edge 122b of the stopper part 122, and its protruding end edge 123a abuts against the open end 11b of the valve body 11 and is fixed to the open end 11b. As a result, when the piston 221 abuts the stopper part 122 with a large impact load due to the use of ultra-high pressure fluid in the refrigeration cycle system, the stopper part 122 is positioned away from the welded portion 16, which is the fixing part between the valve body 11 and the cover member 12, and is located axially D11 outward from the valve body 11. Therefore, it is difficult for stress to directly act on the welded portion 16 as a stress that tries to separate the two, and thus the durability of the cover member 12 against the impact load when the piston 221 abuts the stopper part 122 can be improved.

[0041] <Shock stress relief means (2) (flexural deformation)> As described above, the impact stress relief means (1) (arrangement of the impact stress relief section) can relieve the stress caused by the collision load when the piston 221 contacts the stopper section 122 under normal operating conditions. However, under high-load operating conditions, for example, the differential pressure between high and low pressure becomes large, and the collision load when the piston 221 contacts the stopper section 122 may become excessive. In such cases, the impact stress relief means (2) (flexural deformation) further relieves the stress generated in the welded section 16 due to the impact when the piston 221 contacts the stopper section 122 by the stopper section 122 flexuring within its elastic range in the axial direction D11, and by the impact stress relief section 123 flexuring within its elastic range in the direction D12 intersecting the axial direction D11. This relief effect by the impact stress relief means (2) (flexural deformation) improves the durability of the lid member 12 against the collision load when the piston 221 contacts the stopper section 122. Furthermore, Figure 4 shows the deflection deformation of the impact stress relief section 123 when the piston 221 makes contact, depicted by dotted lines. Note that this deflection deformation shown by dotted lines is exaggerated for clarity.

[0042] Here, when the length of the cylindrical impact stress relief section 123 in the axial direction D11 is L and the thickness of the cylindrical wall 123b is T, 0.5T≦L (Formula 1) It is preferable that the relationship is satisfied. L≦5T (Formula 2) It is even more desirable to satisfy the relationship.

[0043] Furthermore, the thickness T of the cylindrical wall 123b in the impact stress relaxation section 123 preferably satisfies the following relationship, where t is the thickness of the cylindrical wall 111 in the cylindrical valve body 11. 0.5t ≤ T ≤ 1.5t ... (Equation 3)

[0044] Figure 6 is a graph showing the change in stress relaxation effect of the impact stress relaxation section 123 shown in Figure 4, when the axial length L is changed with respect to the thickness T of the cylindrical wall, for various cylindrical wall thicknesses T.

[0045] In Graph G shown in Figure 6, the horizontal axis represents the ratio of the axial length D11 L of the impact stress relief section 123 to the thickness T of the cylinder wall 123b. The vertical axis represents the stress relief effect of the impact stress relief section 123, expressed as a stress ratio with the stress value at L=0 being 100%. Graph G shows the change curves F11, F12, F13, F14, and F15 of the change in the stress ratio relative to the axial length D11 L for five different types of impact stress relief sections 123, each with a different ratio of the thickness T of the cylinder wall 123b to the thickness t of the cylinder wall 111 in the valve body 11. From these stress ratio change curves F11, F12, F13, F14, and F15, it can be seen that when 0.5T ≤ L is satisfied, the stress ratio decreases to 1.0 or less, i.e., the stress relief effect becomes significant. Furthermore, the stress ratio change curves F11, F12, F13, F14, and F15 suggest that this change in stress relaxation effect is effectively manifested when 0.5t ≤ T ≤ 1.5t is satisfied.

[0046] Figure 7 shows the first to third modified versions of the impact stress relaxation section 123 shown in Figure 4, with the stress relaxation effect expected from the graph shown in Figure 6, in the same enlarged cross-section as in Figure 4. Figure 8 also shows the fourth to sixth modified versions of the impact stress relaxation section 123 shown in Figure 4, with the stress relaxation effect expected from the graph shown in Figure 6, in the same enlarged cross-section as in Figure 4. In Figures 7 and 8, components equivalent to those shown in Figure 4 are denoted by the same reference numerals as in Figure 4 only if necessary for the explanation here, and redundant explanations of these components are omitted below. Figure 7(A) shows the first modified version, Figure 7(B) shows the second modified version, and Figure 7(C) shows the third modified version. Figure 8(A) shows the fourth modified version, Figure 8(B) shows the fifth modified version, and Figure 8(C) shows the sixth modified version.

[0047] First, in the impact stress relief section 123 shown in Figure 4, the ratio of the thickness T of the cylindrical wall 123b to the thickness t of the cylindrical wall 111 in the valve body 11 is T = 0.95t, which satisfies the relationship (Equation 3) described above. Furthermore, the ratio of the length L of the axial direction D11 to the thickness T of the cylindrical wall 123b in the impact stress relief section 123 is L = 1.2T, which satisfies the relationship (Equation 1) described above.

[0048] Next, in the impact stress relief sections 123-1, 123-2, and 123-3 of the first to third modified examples shown in Figure 7, the ratio of the thickness T of the cylindrical walls 123-1b, 123-2b, and 123-3b to the thickness t of the cylindrical wall 111 in the valve body 11 is T=1t. Similarly, in the impact stress relief sections 123-4 and 123-6 of the fourth and sixth modified examples shown in Figure 8, the ratio of the thickness T of the cylindrical walls 123-4b and 123-6b to the thickness t of the cylindrical wall 111 in the valve body 11 is T=1t. On the other hand, in the impact stress relief section 123-5 of the fifth modified example, due to the formation of the small-diameter recess 123-5c described later, the ratio of the thickness T of the cylindrical wall 123-5b to the thickness t of the cylindrical wall 111 in the valve body 11 is T=0.5t. These ratios, like the impact stress relaxation section 123 shown in Figure 4, also satisfy the relationship in (Equation 3) described above.

[0049] In the impact stress relief section 123-1 of the first modified example shown in Figure 7(A), the ratio of the length L of the axial direction D11 to the thickness T of the cylindrical wall 123-1b is L=0.5T. In the impact stress relief section 123-2 of the second modified example shown in Figure 7(B), L=1T, and in the impact stress relief section 123-3 of the third modified example shown in Figure 7(C), L=2T. All three of these ratios satisfy the relationship in (Equation 1) described above, similar to the impact stress relief section 123 shown in Figure 4. Furthermore, in the impact stress relief section 123-4 of the fourth modified example shown in Figure 8(A), L=2T, in the impact stress relief section 123-5 of the fifth modified example shown in Figure 8(B), L=2.5T, and in the impact stress relief section 123-6 of the sixth modified example shown in Figure 8(C), L=5T. These three ratios also satisfy the relationship in (Equation 1) described above. Here, if this ratio deviates from the relationship in (Equation 2) above and L > 5T, the axial D11 of the lid member including the impact stress relief section becomes noticeably larger. The relationship L ≤ 5T in (Equation 2) above is an upper limit provision to suppress this increase in the axial D11 of the impact stress relief section.

[0050] Furthermore, in the impact stress relief section 123 of the embodiment shown in Figure 4, and in the impact stress relief sections 123-1, 123-2, and 123-3 of the first to third modified examples shown in Figure 7, the following small-diameter cylindrical projection 123c is provided. Note that this small-diameter cylindrical projection is equivalent to the same part in the embodiment in Figure 4 and the first to third modified examples in Figure 7, so the same reference numeral "123c" is used in both Figure 4 and Figure 7.

[0051] The small-diameter cylindrical projection 123c is a portion that protrudes cylindrically in the axial direction D11 toward the opening 11a side of the valve body 11 from a position closer to the inner circumference of the protruding end edge 123a of the impact stress relief portion 123,...,123-3. This small-diameter cylindrical projection 123c has a smaller diameter than the outer diameter of the impact stress relief portion 123,...,123-3. On the other hand, the opening end 11b of the valve body 11 is provided with a positioning recess 11c at a position closer to the inner circumference of the opening end 11b, into which the small-diameter cylindrical projection 123c is fitted to position the cover member 12 when it is attached.

[0052] Furthermore, in this embodiment and the first to third modifications, the fixing portion between the valve body 11 and the cover member 12 is a welded portion 16 formed by welding as described above. This welded portion 16 is formed such that its welding depth Dp is such that it does not penetrate the small-diameter cylindrical projection 123c in the thickness direction D13.

[0053] Furthermore, in the impact stress relaxation sections 123-4, 123-5, and 123-6 of the fourth to sixth modified examples shown in Figure 8, unlike the embodiments described above and the first to third modified examples, the following small-diameter recesses 123-4c, 123-5c, and 123-6c are provided.

[0054] The small-diameter recesses 123-4c, 123-5c, and 123-6c are portions that are recessed to a smaller diameter than the outer diameter of the impact stress relief portions 123-4, 123-5, and 123-6, extending axially D11 toward the stopper portion 122 from a position closer to the inner circumference of the protruding edge 123a of the impact stress relief portions 123-4, 123-5, and 123-6. On the other hand, the open end 11b of the valve body 11 is provided with positioning protrusions 11-4c, 11-5c, and 11-6c, which are fitted into the small-diameter recesses 123-4c, 123-5c, and 123-6c mentioned above, at a position closer to the inner circumference of the open end 11b, thereby positioning the cover member 12 when it is installed.

[0055] In the fourth to sixth modifications, the lengths of the axial D11 of the small diameter recesses 123-4c, 123-5c, and 123-6c are different. In the fifth modification, the small diameter recess 123-5c is formed along the entire length of the impact stress relief portion 123-5, reaching the outer peripheral edge 122b of the stopper portion 122 in terms of axial D11. As a result, as described above, the impact stress relief portion 123-5 in the fifth modification is thin, with a ratio of the thickness T of the cylindrical wall 123-5b to the thickness t of the cylindrical wall 111 in the valve body 11 being T = 0.5t. In the fourth and sixth modifications, the positioning protrusions 11-4c and 11-6c protrude to a length corresponding to the length of the axial D11 of the small diameter recesses 123-4c and 123-6c that are fitted into them. In the fifth modification, the positioning projection 11-5c is approximately the same length as the positioning projection 11-4c in the fourth modification, and is fitted into the small-diameter recess 123-5c partway towards the opening. In the fourth to sixth modifications, by providing such positioning projections 11-4c, 11-5c, and 11-6c on the valve body 11, the piston 221 is configured to remain inside the valve body 11 when it contacts the stopper portion 122, while the length L of the impact stress relief portions 123-4, 123-5, and 123-6 can be made longer than in the first to third modifications, such as 2T to 5T, thereby further reducing the stress generated in the welded portion 16 due to the impact when the piston 221 contacts the stopper portion 122.

[0056] Furthermore, in the fourth to sixth modifications, the welded portion 16, which serves as the fixing portion between the valve body 11 and the cover member 12, is formed such that its welding depth Dp is such that it does not penetrate the positioning protrusions 11-4c, 11-5c, and 11-6c in the thickness direction D13.

[0057] The following effects can be obtained with the slide-type switching valve 10 and refrigeration cycle system 30 of the embodiments and the first to sixth modified examples described above. Specifically, in this embodiment and the first to sixth modified examples, in the lid member 12, an impact stress relief means (1) (arrangement of impact stress relief part) is employed as an impact stress relief means to relieve the stress caused by the impact when the piston 221 contacts the stopper part 122.

[0058] The impact stress relief means (1) (arrangement of the impact stress relief part) is a means of providing impact stress relief parts 123, ..., 123-6 between the stopper part 122 and the open end 11b of the valve body 11, which protrude in the axial direction D11 from the outer peripheral edge 122b of the stopper part 122, and whose protruding end edge 123a abuts against the open end 11b of the valve body 11 and is fixed to the open end 11b. As a result, when the piston 221 abuts the stopper part 122 with a large impact load due to the use of ultra-high pressure fluid in the refrigeration cycle system, the stopper part 122 receives the impact load at a position away from the welded portion 16 between the valve body 11 and the cover member 12, outward in the axial direction D11 of the valve body 11. Therefore, the impact load is less likely to directly act on the welded portion 16 as a stress that tries to separate the two, and thus the durability of the cover member 12 against the impact load when the piston 221 abuts the stopper part 122 can be improved.

[0059] Next, the impact stress relief means (2) (flexural deformation) is a means of relieving the stress generated in the welded portion 16 by the impact when the piston 221 contacts the stopper portion 122. For example, when the operating conditions become high-load operating conditions and the differential pressure between high and low pressure becomes large, causing the impact load when the piston 221 contacts the stopper portion 122 to become excessive, the stopper portion 122 deforms flexurally in the axial direction D11 within its elastic range, and the impact stress relief portions 123, ..., 123-6 deform flexurally in the direction D12 intersecting the axial direction D11 within their elastic range. In other words, even with the impact stress relief means (2) (flexural deformation), the impact load at the time of contact becomes less likely to act as a stress that tries to separate the welded portion 16 between the open end 11b of the valve body 11 and the cover member 12. As a result, the durability of the cover member 12 against the impact load when the piston 221 contacts the stopper portion 122 can be improved.

[0060] In this embodiment and the first to sixth modifications, the impact stress relief sections 123, ..., 123-3 are formed such that the length L in the axial direction D11 and the thickness T of the cylindrical wall 123b, ..., 123-3b satisfy the relationship 0.5T ≤ L. With this configuration, the length L in the axial direction D11 of the impact stress relief sections 123, ..., 123-6 is made sufficiently long, so that the stopper section 122 is positioned sufficiently far outward in the axial direction D11 from the welded portion 16 between the valve body 11 and the cover member 12. With this arrangement, stress at the welded portion 16 can be relieved more effectively.

[0061] Furthermore, in this embodiment and the first to sixth modifications, the impact stress relief sections 123, ..., 123-6 are formed to satisfy the relationship L ≤ 5T. This configuration allows for effective stress relief while suppressing an increase in the size of the cover member 12, including the impact stress relief sections 123, ..., 123-6, i.e., the sliding type switching valve 10.

[0062] Furthermore, in this embodiment and the first to third modifications, small-diameter cylindrical projections 123c are provided on the impact stress relief sections 123, ..., 123-3, and a positioning recess 11c is provided on the open end 11b of the valve body 11. Furthermore, in the fourth to sixth modifications, small-diameter recesses 123-4c, 123-5c, 123-6c are provided on the impact stress relief sections 123-4, 123-5, 123-6, and positioning protrusions 11-4c, 11-5c, 11-6c are provided on the open end 11b of the valve body 11. With these configurations, the lid member 12 is positioned relative to the opening 11a of the valve body 11 by fitting the small-diameter cylindrical projection 123c into the positioning recess 11c, or by fitting the positioning protrusions 11-4c, 11-5c, 11-6c into the small-diameter recesses 123-4c, 123-5c, 123-6c, thus allowing subsequent fixing work to be performed with good workability.

[0063] Furthermore, in this embodiment and the first to sixth modifications, the fixing portion between the valve body 11 and the cover member 12 is a welded portion 16, and this welded portion 16 is formed with a welding depth Dp that does not penetrate the small-diameter cylindrical projection 123c or the positioning protrusions 11-4c, 11-5c, 11-6c in the thickness direction D13. With this configuration, since the welded portion 16, which serves as the fixing portion, does not penetrate the small-diameter cylindrical projection 123c or the positioning protrusions 11-4c, 11-5c, 11-6c on the cover member 12, it is possible to effectively prevent spatter from entering the inside of the valve body 11 during welding.

[0064] Furthermore, the embodiments and modifications described above, as well as the first to sixth modifications, represent only representative forms of the present invention, and the present invention is not limited thereto. That is, the present invention can be implemented with various modifications without departing from the core principles. As long as such modifications still possess the configuration of the slide-type switching valve and refrigeration cycle system of the present invention, they are of course included within the scope of the present invention.

[0065] For example, in the above-described embodiment and the first to sixth modifications, a slide-type diverter valve 10 is exemplified as an example of a slide-type diverter valve, which is a four-way diverter valve that switches the connection state of four pipes. However, a slide-type diverter valve is not limited to a four-way diverter valve. A slide-type diverter valve may be a three-way diverter valve that switches the pipes to be connected when connecting, for example, one pair of pipes out of three, using a slide valve body, as long as at least one pair of pipes is connected to the valve housing. Alternatively, it may be a two-way diverter valve that opens and closes the connection between two pipes using a slide valve body. The number of pipes in a slide-type diverter valve, the method of switching the connection state, etc., can be appropriately set according to the target application of the slide-type diverter valve.

[0066] Furthermore, in the above-described embodiments and the first to sixth modifications, a valve housing 1 is exemplified as an example of a valve housing in which the openings 11a at both ends of a cylindrical valve body 11 are closed by a cover member 12 having a dome-shaped covered cylindrical cover body portion 121. However, the valve housing is not limited to this, and the valve body may be cylindrical in a shape other than a cylinder, and the cover member may also be cylindrical in a shape other than a dome-shaped covered cylinder, as long as it closes the opening of the valve body.

[0067] Furthermore, in the above-described embodiments and the first to sixth modifications, impact stress relief sections 123, ..., 123-6 are exemplified as examples of impact stress relief sections, where the thickness T of the cylinder wall 123b and the thickness t of the cylinder wall 111 in the valve body 11 satisfy the relationship 0.5t ≤ T ≤ 1.5t. However, the impact stress relief section is not limited to this, and may be formed to deviate from this relationship. However, as mentioned above, the relationship 0.5t ≤ T ≤ 1.5t is a preferred relationship in terms of the stress relief effect at the welded portion 16. In addition, in the embodiments and the first to sixth modifications, impact stress relief section 123 with T = 0.95t and impact stress relief sections 123-1, ..., 123-6 with T = 1t are exemplified as specific examples that satisfy this relationship. However, the impact stress relief section that satisfies the relationship 0.5t ≤ T ≤ 1.5t is not limited to this, and any thickness that satisfies the above relationship can be adopted as the thickness of the cylinder wall.

[0068] Furthermore, in the above-described embodiments and the first to sixth modifications, as an example of an impact stress relief section, impact stress relief sections 123,..., 123-6 are provided that satisfy the relationship 0.5T ≤ L between the length L in the axial direction D11 and the thickness T of the cylindrical walls 123b,..., 123-6b. However, the impact stress relief section is not limited to this, and may be formed such that the axial length is 0.5T > L. However, as mentioned above, impact stress relief sections 123,..., 123-6 formed to satisfy the relationship 0.5T ≤ L can be made more flexible, thereby more effectively relieving stress in the welded portion 16. In addition, in the embodiments and the first to sixth modifications, specific examples that satisfy this relationship are provided, such as impact stress relief section 123 with L = 1.2T and impact stress relief sections 123-1,..., 123-6 with L = 0.5T, 1T, 2T, 2.5T, and 5T. However, the impact stress relaxation section that satisfies the relationship 0.5T ≤ L is not limited to this, and any thickness that satisfies the above relationship can be adopted as the thickness of the cylinder wall.

[0069] Furthermore, in the above-described embodiments and the first to sixth modifications, as an example of an impact stress relief section, impact stress relief sections 123, ..., 123-6 are provided that satisfy the relationship L ≤ 5T in addition to the relationship 0.5T ≤ L. However, the impact stress relief section is not limited to this, and may be formed such that L > 5T while satisfying the relationship 0.5T ≤ L. However, as mentioned above, the impact stress relief sections 123, ..., 123-6 formed to satisfy the relationship L ≤ 5T can suppress the enlargement of the slide-type switching valve 10. In addition, in the embodiments and the first to sixth modifications, as specific examples that satisfy this relationship, impact stress relief section 123 with L = 1.2T and impact stress relief sections 123-1, ..., 123-6 with L = 0.5T, 1T, 2T, 2.5T, 5T are provided. However, the impact stress relaxation section that satisfies the relationship L ≤ 5T is not limited to this, and any thickness that satisfies the above relationship can be adopted as the thickness of the cylinder wall.

[0070] Furthermore, in the above-described embodiments and the first to sixth modifications, examples of impact stress relief sections and valve bodies are provided, such as impact stress relief sections 123, ..., 123-6 provided with small-diameter cylindrical projections 123c or small-diameter recesses 123-4c, 123-5c, 123-6c, and a valve body 11 provided with positioning recesses 11c or positioning protrusions 11-4c, 11-5c, 11-6c. However, the impact stress relief sections and valve bodies are not limited to these, and may be provided without small-diameter cylindrical projections, small-diameter recesses, positioning recesses, or positioning protrusions. However, as mentioned above, by providing small-diameter cylindrical protrusions 123c, small-diameter recesses 123-4c, 123-5c, 123-6c, positioning recesses 11c, and positioning protrusions 11-4c, 11-5c, 11-6c on the impact stress relief sections 123, ..., 123-6 and the valve body 11, the fixing work of the cover member 12 to the opening 11a of the valve body 11 can be performed with good workability.

[0071] Furthermore, in the above-described embodiments and the first to third modifications, a valve housing 1 is provided as an example of a valve housing in which the valve body 11 and the cover member 12 are fixed by forming a welded portion 16 with a welding depth Dp that does not penetrate the small-diameter cylindrical projection 123c or the positioning protrusions 11-4c, 11-5c, 11-6c. However, the valve housing is not limited to this, and the cover member may be fixed to the valve body by a welded portion formed with a welding depth that penetrates the small-diameter cylindrical projection or the positioning protrusion. However, as mentioned above, forming the welded portion 16 with a welding depth Dp that does not penetrate the small-diameter cylindrical projection 123c or the positioning protrusions 11-4c, 11-5c, 11-6c effectively prevents spatter from entering the inside of the valve body 11 during welding. [Explanation of Symbols]

[0072] 1 Valve housing 1A High-voltage chamber 1B First Working Room 1C Second Working Chamber 2. Slide valve body 3. Pilot valve 10. Slide-type switching valve 11 Valve body 11a opening 11b Open end 11c Positioning recess 11-4c, 11-5c, 11-6c Positioning protrusions 12 Lid member 13c C fitting pipe 13d D-type fitting pipe 13e E-fitting pipe 13s S-type fitting pipe 14L Thin tube for the first housing 14R Second housing tube 16. Welded parts 21 Valve body 21A Bowl-shaped recess 22. Slide mechanism 30 Refrigeration Cycle Systems 31 Compressor 32 Outdoor heat exchanger 33 Indoor heat exchanger 34 Aperture device 121 Lid body part 121a Cylinder opening 121b Opening edge 121c mounting hole 122 Stopper section 122a Stopper surface 122b Outer edge 123, 123-1, 123-2, 123-3, 123-4, 123-5, 123-6 Impact stress relaxation section 123a Protruding edge 123b,123-1b,123-2b,123-3b,123-4b,123-5b,123-6b Cylinder wall 123c Small diameter cylindrical projection 123-4c, 123-5c, 123-6c Small diameter recess 221 Piston 222 Connecting plate 222a Through hole D11 Axial direction D12 Intersecting direction D13 Thickness direction Dp Weld Depth F11, F12, F13, F14, F15 Stress Ratio Change Curve G-graph T Thickness of the cylindrical wall in the impact stress relaxation section t Thickness of the cylindrical wall in the valve body L Axial length in the impact stress relaxation section X axis φ11 Inner diameter of the valve body opening φ12 Outer diameter of the lid body φ13 Inner diameter of the stopper part φ14 Outer diameter of valve body

Claims

1. A valve housing having a cylindrical shape, with at least one pair of pipes connected to its peripheral wall, and openings at both ends of the valve body closed by cover members, Inside the valve body, there is a valve element that is slidably installed in the axial direction of the valve body to switch the communication state of the piping, A mechanism portion located inside the valve body, extending in the axial direction and having pistons at both ends, wherein the valve body is connected to the intermediate portion and the pistons provide an axial sliding driving force that causes the valve body to slide, The aforementioned lid member, A lid body portion is formed in the shape of a covered cylindrical shape having an inner diameter smaller than the inner diameter of the opening of the valve body, and is positioned outside the opening of the valve body in the axial direction such that the opening of the cylinder faces the opening of the valve body; A flange-like projection extending from the opening edge of the cylindrical opening of the lid body toward the outside of the lid body, having an outer diameter larger than the inner diameter of the opening of the valve body, and a stopper portion that, on the surface facing the opening, abuts against and receives the piston at one end of the sliding mechanism that has slid through the opening in the axial direction, The system includes an impact stress relief means for relieving stress caused by the impact when the piston contacts the stopper portion, The impact stress relief means is a means for relieving the stress, characterized in that an impact stress relief portion is provided between the stopper portion and the opening end of the valve body surrounding the opening, which protrudes in a cylindrical shape in the axial direction from the outer peripheral edge of the stopper portion to the opening end, the inner surface of which is cylindrical is formed flat, and the protruding edge of the cylindrical shape abuts against the opening end of the valve body and is fixed to the opening end.

2. The slide-type switching valve according to claim 1, characterized in that the impact stress relief means, in addition to the installation of the impact stress relief portion, also relieves the stress by causing the stopper portion to bend and deform in the axial direction due to the impact when the stopper portion comes into contact with the piston, and by causing the impact stress relief portion to bend and deform in a direction intersecting the axial direction.

3. The cylindrical impact stress relief portion has an axial length L and a wall thickness T, 0.5T ≤ L A sliding switching valve according to claim 1, characterized in that it is formed to satisfy the relationship.

4. The aforementioned impact stress relief section further, L ≤ 5T A sliding switching valve according to claim 3, characterized in that it is formed to satisfy the relationship.

5. The impact stress relief portion is provided with a small-diameter cylindrical projection that protrudes in a cylindrical shape with a smaller diameter than the outer diameter of the impact stress relief portion, extending axially from a position near the inner circumference of the protruding edge toward the opening side of the valve body, or a small-diameter recess that is recessed to a smaller diameter than the outer diameter of the impact stress relief portion, extending axially from a position near the inner circumference of the protruding edge toward the stopper portion. The sliding switching valve according to claim 1, characterized in that the opening end of the valve body is provided with a positioning recess at a position closer to the inner circumference of the opening end into which the small-diameter cylindrical projection of the impact stress relief portion is fitted to position the cover member when it is attached, or a positioning protrusion at a position closer to the inner circumference of the opening end into which the small-diameter recess of the impact stress relief portion is fitted to position the cover member when it is attached.

6. The sliding switching valve according to claim 5, wherein the fixing portion between the valve body and the cover member is a welded portion formed by welding the protruding edge of the valve body to the opening end of the valve body from the outer peripheral surface side of the valve body, and is formed with a welding depth that does not penetrate the small diameter cylindrical projection or the positioning projection in the thickness direction.

7. A refrigeration cycle system comprising: a compressor for compressing a refrigerant, which is a fluid; a first heat exchanger that functions as a condenser in cooling mode; a second heat exchanger that functions as an evaporator in cooling mode; an expansion means for expanding and reducing the pressure of the refrigerant between the first heat exchanger and the second heat exchanger; and a slide-type switching valve as described in any one of claims 1 to 6.

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