Sliding type switching valve and refrigeration cycle system

Abstract

The invention provides a sliding type switching valve and a refrigeration cycle system, which can improve the durability of a collision load when a piston abuts against a stop part of a cover component. A cover member (12) in a valve housing of a sliding switching valve is provided with: a cover main body section (121); a stopper part (122) which extends in a flange shape from the cover main body part, and which comes into contact with and blocks a piston (221) of a slide mechanism (22); and an impact stress relaxation means that relaxes stress generated by an impact when the piston comes into contact with the stopper. And an impact stress relaxation means for relaxing stress by providing an impact stress relaxation section (123) between the stopper section and the open end (11b) of the valve main body (11), the impact stress relaxation section (123) protruding in a cylindrical shape in the axial direction from the outer peripheral edge (122b) of the stopper section, the protruding end edge (123a) of the impact stress relaxation section (123) being in contact with the open end of the valve main body and being fixed to the open end.

Description

Technical Field

[0001] The present invention relates to a sliding switching valve and a refrigeration cycle system, which are used in a refrigeration cycle system such as an air conditioner and switch the flow path of a refrigerant. Background Art

[0002] In the past, a sliding type switching valve is known, in which a valve core is housed inside a valve housing whose openings at both ends of a cylindrical valve body are blocked by a cover member (for example, refer to Patent Document 1). In the sliding type switching valve described in Patent Document 1, inside the valve housing, a valve core is connected to a sliding mechanism that moves when a piston receives a sliding driving force, and the valve core moves together with the sliding mechanism. Among them, in the sliding type switching valve, the cover member includes: a cover body portion having a cylindrical cover; and a flange-shaped portion, which protrudes in a flange shape and is fixed to the opening end of the valve body at a portion close to the outer peripheral edge. A portion of the flange-shaped portion of the cover member protrudes toward the inner side of the valve body, and the protruding surface portion becomes a stopper that abuts and stops the piston of the sliding mechanism that moves together with the valve core.

[0003] Prior art literature

[0004] Patent Document 1: Japanese Patent Application Publication No. 2023-120826

[0005] In the above-mentioned sliding switching valve, when the piston abuts against the stopper, the collision load during the abutment is transmitted to the fixed part of the flange-shaped part of the cover member and the opening end of the valve body, thereby generating stress that tends to peel off the flange-shaped part of the cover member from the opening end of the valve body in the axial direction. In recent years, the fluid of the refrigeration cycle system that imparts sliding driving force to the piston sometimes uses ultra-high pressure fluids such as CO2. In this case, the collision load when the piston abuts against the stopper may become too large. Therefore, it is required to improve the durability against such excessive collision loads. Summary of the invention

[0006] An object of the present invention is to provide a slide-type switching valve and a refrigeration cycle system capable of improving durability against a collision load when a piston abuts against a stopper of a cover member.

[0007] The closure of the valve body is connected to the spool of the valve core, and the spool of the valve core is connected to the spool of the valve core by the spool of the piston rod. The outer side; a stopper, which extends from the opening edge of the tube opening of the cover body toward the outer side of the cover body in the shape of a flange having an outer diameter larger than the inner diameter of the opening of the valve body, and abuts and blocks the piston on one end side of the sliding mechanism that slides through the opening in the axial direction on the surface facing the opening side; and an impact stress relief unit, which relieves the stress generated by the impact when the piston abuts against the stopper, the impact stress relief unit being a unit that relieves the stress by providing an impact stress relief unit between the stopper and the opening end of the opening surrounding the valve body, the impact stress relief unit protruding from the outer peripheral edge of the stopper in the shape of a tube along the axial direction, the protruding end edge abuts against the opening end of the valve body and is fixed to the opening end. In addition, the impact stress relief unit may also be a unit that, in addition to providing the impact stress relief portion, relieves the stress by causing the stop portion to bend and deform in the axial direction due to an impact when the stop portion abuts against the piston, and by causing the impact stress relief portion to bend and deform in a direction crossing the axial direction.

[0008] In the sliding switching valve, in the cover part, between the stopper against which the piston of the sliding mechanism abuts and the protruding end edge fixed to the opening end of the valve body, an impact stress relief unit is provided to relieve the stress generated in the fixed part of the valve body and the cover part by the impact of the abutment of the piston. According to the impact stress relief unit, by providing the impact stress relief unit between the stopper and the opening end of the valve body, the stopper is arranged at a position away from the fixed part of the valve body and the cover part toward the axial outside of the valve body. Thus, by using an ultra-high pressure fluid in the refrigeration cycle system, even when the piston abuts against the stopper with a large collision load, the stress acting on the fixed part of the valve body and the cover part can be relieved. That is, the collision load during abutment is unlikely to act directly on the opening end of the valve body and the fixed part of the cover part as a stress intended to separate the two, so that the durability against the collision load when the stopper of the piston and the cover part abuts can be improved. In addition, by providing the impact stress relief means as a means for relieving stress by bending and deforming the stopper in the axial direction and the impact stress relief part in the cross direction, it is possible to further suppress the collision load from directly acting on the fixed part during abutment, thereby further improving the durability against the collision load.

[0009] Preferably, the cylindrical impact stress alleviating portion is formed to satisfy the relationship of 0.5T≤L, assuming that the length in the axial direction is L and the thickness of the cylindrical wall is T.

[0010] According to this structure, by forming a structure in which the axial length of the impact stress relief portion is sufficiently long and the stop portion is arranged at a position sufficiently far away from the fixed portion of the valve body and the cover member toward the axial outside of the valve body, the stress at the fixed portion of the valve body and the cover member can be further effectively relieved.

[0011] Furthermore, more preferably, the impact stress alleviating portion is formed to satisfy the relationship of L≤5T.

[0012] According to this configuration, stress can be effectively relaxed, and an increase in size of the cover member including the impact stress relaxing portion, that is, the slide-type switching valve, can be suppressed.

[0013] In addition, preferably, the impact stress relief portion is provided with a small-diameter cylindrical protrusion that protrudes from a position near the inner circumference of the protruding end edge along the axial direction toward the opening side of the valve body in a cylindrical shape with a diameter smaller than the outer diameter of the impact stress relief portion, or a small-diameter recessed portion that is recessed from a position near the inner circumference of the protruding end edge along the axial direction toward the stop portion side in a cylindrical shape with a diameter smaller than the outer diameter of the impact stress relief portion, and at the opening end of the valve body, a positioning recess is provided near the inner circumference of the opening end for positioning the cover component during installation by embedding the small-diameter cylindrical protrusion of the impact stress relief portion, or a positioning convex portion is provided near the inner circumference of the opening end for positioning the cover component during installation by embedding in the small-diameter recess of the impact stress relief portion.

[0014] According to this configuration, the small-diameter cylindrical protrusion fits into the positioning recess or the positioning protrusion fits into the small-diameter recess, so that the cover member is positioned at the opening of the valve body. Therefore, the subsequent fixing work can be performed with good workability.

[0015] In addition, more preferably, the fixing portion is a welded portion formed by welding the opening end of the valve body from the outer peripheral surface side of the valve body to the protruding end edge, and is formed with a welding depth that does not penetrate the small-diameter cylindrical protrusion or the positioning protrusion in the thickness direction.

[0016] According to this configuration, the welded portion as the fixing portion is formed at a welding depth that does not penetrate the small-diameter cylindrical protrusion of the cover member or the positioning protrusion of the valve body in the thickness direction, thereby effectively preventing spatter during welding from intruding into the valve body.

[0017] In addition, the refrigeration cycle system of the present invention is characterized in that it comprises: a compressor that compresses the refrigerant as a fluid; a first heat exchanger that acts as a condenser in a cooling mode; a second heat exchanger that acts as an evaporator in a cooling mode; an expansion unit that expands and decompresses the refrigerant between the first heat exchanger and the second heat exchanger; and the above-mentioned sliding switching valve.

[0018] According to this refrigeration cycle system, since the slide-type switching valve is provided, it is possible to improve the durability against the collision load when the piston abuts against the stopper portion of the cover member.

[0019] The effects of the present invention are as follows.

[0020] 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 when the piston abuts against the stopper of the cover member. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1It is a cross-sectional view showing a cross section along the axial direction of the valve housing of a slide-type switching valve according to one embodiment.

[0022] Figure 2 Yes Figure 1 The figure shows an enlarged cross-section of the cover member shown.

[0023] Figure 3 The piston is shown in the state of contact with the stopper of the cover part. Figure 1 A diagram showing the structure of the end portion on the right side of the diagram of the slide-type switching valve shown.

[0024] Figure 4 Yes means Figure 3 An enlarged view of area A11 in FIG.

[0025] Figure 5 Yes means have Figure 1 to Figure 4 A schematic diagram of a refrigeration cycle system with a slide-type switching valve is shown.

[0026] Figure 6 About Figure 4 The impact stress relaxation portion shown is a graph showing changes in the stress relaxation effect when the axial length L is changed relative to the thickness T of the tube wall for various tube wall thicknesses T.

[0027] Figure 7 About Figure 4 The impact stress relief portion shown is based on Figure 4 The same enlarged section shows the Figure 6 The graphs shown are diagrams of first to third modified examples in which the stress relaxation effect can be expected.

[0028] Figure 8 About Figure 4 The impact stress relief portion shown is based on Figure 4 The same enlarged section shows the Figure 6 The graphs shown are graphs of fourth to sixth modified examples in which the stress relaxation effect can be anticipated.

[0029] In the figure: 1-valve housing, 1A-high pressure chamber, 1B-first working chamber, 1C-second working chamber, 2-sliding valve core, 3-pilot valve, 10-sliding switching valve, 11-valve body, 11a-opening, 11b-opening end, 11c-positioning concave portion, 11-4c, 11-5c, 11-6c-positioning convex portion, 12-cover member, 13c-C joint pipe, 13d-D joint pipe, 13e-E joint pipe, 13s-S joint pipe, 14L-first housing capillary tube, 14R—capillary tube for second shell, 16—welding portion, 21—valve core, 21A—bowl-shaped recess, 22—sliding mechanism, 30—refrigeration cycle system, 31—compressor, 32—outdoor heat exchanger, 33—indoor heat exchanger, 34—throttling device, 121—cover body, 121a—cylinder opening, 121b—opening edge, 121c—installation hole, 122—stop portion, 122a—stop surface, 122b—outer peripheral edge, 123, 123-1, 123-2, 123-3, 123-4, 123-5, 123-6—impact stress relief portion, 123a—protruding edge, 123b, 123-1b, 123-2b, 123-3b, 123-4b, 123-5b, 123-6b—cylinder wall, 123c—small-diameter cylindrical protrusion, 123-4c, 123-5c, 123-6c—small-diameter recess, 221—piston, 222—connecting plate, 222a—through hole, D11— Axial direction, D12—cross direction, D13—thickness direction, Dp—welding depth, F11, F12, F13, F14, F15—stress ratio change curve, G—curve graph, T—thickness of the cylinder wall in the impact stress relief portion, t—thickness of the cylinder wall in the valve body, L—axial length of the impact stress relief portion, X—axis line, Φ11—inner diameter of the opening of the valve body, Φ12—outer diameter of the cover body, Φ13—inner diameter of the stopper, Φ14—outer diameter of the valve body. DETAILED DESCRIPTION

[0030] The following is based on Figure 1 to Figure 5 A slide-type switching valve and a refrigeration cycle system according to an embodiment of the present invention will be described.

[0031] Figure 1 It is a cross-sectional view showing a cross section along the axial direction of the valve housing of a slide-type switching valve according to one embodiment. Figure 2 Yes Figure 1 The figure shows an enlarged cross-section of the cover member shown. Figure 3 The piston is shown in the state of contact with the stopper of the cover part. Figure 1 The diagram of the end structure on the right side of the figure of the sliding switching valve shown, Figure 4 Yes means Figure 3 An enlarged view of area A11 in FIG. Figure 5 Yes means have Figure 1 to Figure 4Schematic diagram of a refrigeration cycle system with a sliding switching valve shown in FIG. Figure 1 as well as Figure 5 In the figure, the side where the E joint pipe 13e is shown is referred to as the left side, and the side where the C joint pipe 13c is shown is referred to as the right side.

[0032] like Figure 1 As shown, the slide type switching valve 10 of the present embodiment is a four-way switching valve that switches the communication states of four pipes, and has a structure in which a sliding valve element 2 is provided in a valve housing 1 .

[0033] 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 in such a manner as to block the openings 11a at both ends of the valve body 11. In the present embodiment, the cover members 12 are fixed to the valve body 11 by welding from the outer peripheral surface side of the valve body 11. Figure 2 FIG. 1 shows the cover member 12 in a single product state before welding. Figure 3 2 shows a state where the cover member 12 is welded to the valve body 11 together with a part of the piston 221 in the sliding valve element 2 .

[0034] The valve body 11 and the cover member 12 are made of metal such as stainless steel or brass. As a method for fixing such metal parts to each other, welding and brazing can be cited. However, when welding is adopted as in the present embodiment, it is preferable that the valve body 11 and the cover member 12 as the fixing objects are made of stainless steel. In addition, the central axis of the valve body 11 and the cover member 12 is the axis line X of the valve housing 1. Four pipes, namely, a D joint pipe 13d, an E joint pipe 13e, an S joint pipe 13s, and a C joint pipe 13c, which will be described in detail later, are connected to the peripheral wall of the valve housing 1 so as to communicate with the inside of the valve housing 1.

[0035] A valve seat 15 is provided on the inner peripheral surface of the valve body 11, on which the valve core 21 slides and rubs. The valve seat 15 is disposed in the middle portion of the valve body 11, and a D-joint pipe 13d as a high-pressure pipe opening into the valve body 11 is installed at a position of the middle portion of the valve body 11 that faces the valve seat 15. In addition, an E-joint pipe 13e and a C-joint pipe 13c as a pair of conduits, and an S-joint pipe 13s as a low-pressure pipe are installed on the valve seat 15 in a straight line in the axis X direction of the valve housing 1.

[0036] The sliding valve element 2 is a member that is slidably provided in the axial direction D11 of the valve body 11 and switches the communication state of the four pipes. The sliding valve element 2 includes a valve element 21 and a sliding mechanism 22 .

[0037] The valve core 21 switches the communication state of the above four pipes by sliding in the axial direction D11. A bowl-shaped recess 21A is formed inside the valve core 21. Figure 1 The left end position of the valve body 1 is connected to 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 is connected to the D joint pipe 13d mainly through the through hole 222a of the connecting plate 222 of the sliding mechanism 22 in the high pressure chamber 1A divided by the pistons 221 at both ends of the sliding mechanism 22 inside the valve housing 1. Figure 1 At the right end position of the sliding valve body 2 moving to the right, the S joint pipe 13s and the C joint pipe 13c are connected through the bowl-shaped recess 21A. At this time, the E joint pipe 13e is connected to the D joint pipe 13d mainly through the through hole 222a in the high pressure chamber 1A.

[0038] The sliding mechanism 22 is a mechanism portion extending along the axial direction D11 inside the valve body 11 and having pistons 221 at both ends. The sliding mechanism 22 is connected to the valve core 21 at its middle portion, and the valve core 21 slides by receiving the sliding driving force of the axial direction D11 through the piston 221. The sliding mechanism 22 includes a pair of pistons 221 and a connecting plate 222. The pair of pistons 221 are respectively configured in a substantially circular plate shape and are arranged in a manner of sandwiching the valve core 21 in the axial direction D11. The connecting plate 222 is a plate member extending in the axial direction D11, and is connected to the valve core 21 in its middle portion in a manner that allows it to slide on the valve seat 15, and the pistons 221 are fixed at both ends. In addition, in the connecting plate 222, one of the above-mentioned through holes 222a is provided at a position that is in the middle of the valve core 21 and each piston 221.

[0039] The interior of the valve housing 1 is divided into a high-pressure chamber 1A in the center and a first working chamber 1B and a second working chamber 1C located on both sides of the high-pressure chamber 1A by pistons 221 at both ends of the sliding mechanism 22. Figure 5 The pilot valve 3 shown in the figure flows into the first working chamber 1B and the second working chamber 1C, and the pistons 221 at the respective ends receive the sliding driving force through the driving fluid.

[0040] exist Figure 5In the refrigeration cycle system 30 shown, 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 throttle device 34 (expansion unit). The refrigeration cycle system 30 is constituted by a path consisting of the C-joint pipe 13c to the outdoor heat exchanger 32, the throttle device 34, the indoor heat exchanger 33, and the E-joint pipe 13e, and a path consisting of the S-joint pipe 13s to the compressor 31 and the D-joint pipe 13d. In addition, the refrigerant in the refrigeration cycle system 30 contains a small amount of refrigeration oil in order to protect the compressor 31 and other equipment.

[0041] Figure 5 The pilot valve 3 shown in the figure allows the driving fluid to flow through a pair of spaces, namely, the first working chamber 1B and the second working chamber 1C, which sandwich the sliding valve element 2 in the axial direction D11 inside the valve housing 1, so that the sliding valve element 2 slides in the axial direction D11. In the present embodiment, the pilot valve 3 allows the fluid of the D joint pipe 13d, which is a high-pressure pipe, to flow through one of the first working chamber 1B and the second working chamber 1C, and allows the fluid of the S joint pipe 13s, which is a low-pressure pipe, to flow through the other, so that the sliding valve element 2 slides.

[0042] The pilot valve 3 has the same structure as the sliding switching valve 10, and the pilot valve core inside the pilot valve housing is slid to switch the flow path. The pilot valve core switches the connection target of the low-pressure joint capillary tube 14s connected to the S joint pipe 13s, which is the low-pressure piping connected to the suction port of the compressor 31, as follows. That is, the pilot valve core switches the connection target of the low-pressure joint capillary tube 14s through the first housing capillary tube 14L connected to the first working chamber 1B of the sliding switching valve 10 and the second housing capillary tube 14R connected to the second working chamber 1C. At the same time, the connection target of the high-pressure joint capillary tube 14d connected to the D joint pipe 13d, which is the high-pressure piping connected to the discharge port of the compressor 31, is switched through the second housing capillary tube 14R and the first housing capillary tube 14L. Thus, a pressure difference is generated between the pressure of the first working chamber 1B and the pressure of the second working chamber 1C into which the suction pressure and discharge pressure of the compressor 31 are introduced, and the pressure difference acts on the pair of pistons 221, so that the sliding valve core 2 slides along the axial direction D11 from the high-pressure side to the low-pressure side. And, by this sliding movement, the position of the valve core 21 in the sliding valve core 2 is switched to switch the flow path of the refrigeration cycle system 30.

[0043] According to the above structure, the high-pressure refrigerant compressed by the compressor 31 flows into the high-pressure chamber 1A from the D joint pipe 13d, and in the state of cooling operation (cooling mode), the high-pressure refrigerant flows into the outdoor heat exchanger 32 from the C joint pipe 13c. In addition, in the state of heating operation (heating mode) with the position of the valve core 21 switched, the high-pressure refrigerant flows into the indoor heat exchanger 33 from the E joint pipe 13e. That is, in the cooling operation, as shown by the solid arrow, the refrigerant discharged from the compressor 31 circulates in the C joint pipe 13c → outdoor heat exchanger 32 → throttle device 34 → indoor heat exchanger 33 → E joint pipe 13e. In this cycle, the outdoor heat exchanger 32 functions as a condenser and the indoor heat exchanger 33 functions as an evaporator to perform cooling. The throttle device 34 expands the refrigerant between the outdoor heat exchanger 32 and the indoor heat exchanger 33 to reduce the pressure. Furthermore, during the heating operation, as indicated by the dotted arrows, the refrigerant circulates in the reverse direction, the indoor heat exchanger 33 functions as a condenser, and the outdoor heat exchanger 32 functions as an evaporator, thereby performing heating.

[0044] In this embodiment, the pair of cover members 12 has the following structure. Figure 1 As shown, a pair of cover members 12 are mirror-symmetrical structures. Figure 2 as well as Figure 3 The structure of the right cover member 12 shown in enlarged form in the figure will be described as a representative example.

[0045] The cover member 12 is a covered cylindrical member having a cover body 121, a stopper 122, and an impact stress relieving portion 123. The cover body 121 is a dome-shaped covered cylindrical portion having an inner diameter Φ12 smaller than the inner diameter Φ11 of the opening 11a of the valve body 11. The cover body 121 is arranged outside the opening 11a of the valve body 11 in the axial direction D11 so that its cylinder opening 121a faces the opening 11a of the valve body 11. The peripheral wall of the cover body 121 is formed with mounting holes 121c for the first housing capillary 14L and the second housing capillary 14R.

[0046] The stopper 122 is a portion extending from the opening edge 121b of the cylinder opening 121a of the cover body 121 toward the outside of the cover body 121 in a flange shape having an outer diameter Φ13 larger than the inner diameter Φ11 of the opening 11a of the valve body 11. In the present embodiment, the outer diameter Φ13 of the stopper 122 is substantially the same as the outer diameter Φ14 of the valve body 11. The stopper surface 122a of the stopper 122 is a surface facing the opening 11a side of the valve body 11, and the piston 221 on one end side of the sliding mechanism 22 that slides through the opening 11a in the axial direction D11 abuts against the stopper surface 122a to restrict the movement of the sliding valve element 2 to the right and left sides in the axial direction D11.

[0047] The impact stress relief portion 123 protrudes in a cylindrical shape in the axial direction D11 from the outer peripheral edge 122b of the stopper 122, and its protruding edge 123a abuts against the opening end 11b of the opening 11a surrounding the valve body 11 and is fixed to the portion of the opening end 11b. As described above, the fixation here is performed by welding. Among them, in this embodiment, the stress generated by the impact when the piston 221 abuts against the stopper 122 is relieved by an impact stress relief unit as described below. The impact stress relief unit has two forms: a unit that relieves stress by configuring the impact stress relief portion 123 and a unit that relieves stress by flexural deformation of the stopper 122 and the impact stress relief portion 123.

[0048] <About impact stress relief unit>

[0049] As described above, in the conventional sliding switching valve, when the piston abuts against the stopper, the collision load during the abutment is transmitted to the fixed part of the flange-shaped portion of the open end of the valve body and the cover member, thereby generating stress that tends to peel the flange-shaped portion of the cover member from the open end of the valve body in the axial direction. Therefore, there is a concern about reduced durability against the collision load when the piston abuts against the stopper.

[0050] In contrast, in the present embodiment, by adopting an impact stress relief unit for relieving stress generated by the impact when the piston 221 and the stopper 122 abut, the cover member 12 can eliminate the conventional problem (stress that tends to peel off the flange-shaped portion of the cover member from the fixed portion between the valve body and the cover member when the piston abuts the stopper), and improve the durability against the collision load when the piston 221 and the stopper 122 abut. The impact stress relief unit in the present embodiment includes the impact stress relief unit (1) (providing an impact stress relief unit) and the impact stress relief unit (2) (bending deformation) as described above, and thus they will be described in sequence below.

[0051] <Impact stress relief unit (1) (impact stress relief unit)>

[0052] like Figure 3As shown, the impact stress relieving means (1) (impact stress relieving portion) is a means in which an impact stress relieving portion 123 is provided between the stopper 122 and the opening end 11b of the valve body 11, and protrudes from the outer peripheral edge 122b of the stopper 122 in the axial direction D11, and its protruding edge 123a abuts against the opening end 11b of the valve body 11 and is fixed to the opening end 11b. Thus, when the piston 221 abuts against the stopper 122 with a large collision load when using an ultra-high pressure fluid in the refrigeration cycle system, the stopper 122 is arranged at a position away from the welded portion 16, which is a fixed portion between the valve body 11 and the cover member 12, to the outside in the axial direction D11 of the valve body 11. Therefore, it is difficult for the stress that tends to separate the two to act directly on the welded portion 16, so that the durability against the collision load when the piston 221 abuts against the stopper 122 of the cover member 12 can be improved.

[0053] <Impact stress relaxation unit (2) (deflection)>

[0054] As described above, the stress caused by the collision load when the piston 221 abuts the stopper 122 under normal operating conditions can be alleviated by the impact stress relief unit (1) (configured with an impact stress relief portion). At this time, for example, under high-load operating conditions, the pressure difference between the high and low pressures becomes larger, and sometimes the collision load when the piston 221 abuts the stopper 122 becomes too large. In such a case, the impact stress relief unit (2) (flexural deformation) is achieved by the stopper 122 being flexibly deformed in the elastic region along the axial direction D11 and the impact stress relief unit 123 being flexibly deformed in the elastic region along the cross direction D12 relative to the axial direction D11, thereby further alleviating the stress generated in the welding portion 16 due to the impact when the piston 221 abuts the stopper 122. This mitigation effect generated by the impact stress relief unit (2) (flexural deformation) can improve the durability against the collision load when the piston 221 abuts the stopper 122 of the cover member 12. In addition, in Figure 4 In FIG. 1 , the dotted line depicts the deflection deformation of the impact stress relief portion 123 when the piston 221 abuts against the impact stress relief portion 123. In addition, the deflection deformation shown by the dotted line is exaggerated for easy viewing.

[0055] The cylindrical impact stress relief portion 123 preferably satisfies the relationship 0.5T≤L...(Formula 1), and more preferably satisfies the relationship L≤5T...(Formula 2), when the axial length D11 is set to L and the thickness of the cylinder wall 123b is set to T.

[0056] In addition, when the thickness of the tube wall 111 of the cylindrical valve body 11 is t, the thickness T of the tube wall 123 b in the impact stress relaxation portion 123 preferably satisfies the following relationship.

[0057] 0.5t≤T≤1.5t···(Formula 3)

[0058] Figure 6 About Figure 4 The impact stress relaxing portion 123 shown is a graph showing changes in the stress relaxing effect when the axial length L is changed relative to the thickness T of the tube wall for various tube wall thicknesses T.

[0059] In this Figure 6 In the graph G shown, the horizontal axis represents the length L of the impact stress relief portion 123 in the axial direction D11 as a ratio to the thickness T of the cylinder wall 123b. In addition, the vertical axis represents the stress relief effect produced by the impact stress relief portion 123 as a stress ratio when the stress value when L=0 is set to 100%. Moreover, in the graph G, for five types of impact stress relief portions 123 with different ratios of the thickness T of the cylinder wall 123b to the thickness t of the cylinder wall 111 of the valve body 11, stress ratio change curves F11, F12, F13, F14, and F15 are drawn with respect to the length L in the axial direction D11. It can be seen from these stress ratio change curves F11, F12, F13, F14, and F15 that when 0.5T≤L is satisfied, the stress ratio is reduced to less than 1.0, that is, the stress relief effect is significantly exhibited. In addition, it can be seen from the stress ratio change curves F11, F12, F13, F14, and F15 that such a change in the stress relaxation effect effectively occurs when 0.5t≤T≤1.5t is satisfied.

[0060] Figure 7 About Figure 4 The impact stress relief portion 123 shown is Figure 4 The same enlarged section shows the Figure 6 The graph shown is a graph of the first to third modified examples of the stress relaxation effect. Figure 8 About Figure 4 The impact stress relief portion 123 shown is Figure 4 The same enlarged section shows the Figure 6 The graph shown is a graph of the fourth to sixth modified examples of the stress relaxation effect. Figure 7 as well as Figure 8 In Figure 4 The same components as those shown in the figure are marked with the same Figure 4 The same reference numerals are used, and repeated description of these components will be omitted below. Figure 7 (A) represents a first modification example, Figure 7 (B) represents a second modification example, Figure 7 (C) represents a third modification. Figure 8 (A) represents the fourth modification example, Figure 8(B) represents a fifth modification example, Figure 8 (C) shows a sixth modification example.

[0061] First, in Figure 4 In the impact stress relief portion 123 shown, the ratio of the thickness T of the tube wall 123b to the thickness t of the tube wall 111 of the valve body 11 is T=0.95t, which satisfies the relationship (Formula 3) above. Furthermore, the ratio of the length L of the axial direction D11 of the impact stress relief portion 123 to the thickness T of the tube wall 123b is L=1.2T, which satisfies the relationship (Formula 1) above.

[0062] Then, in Figure 7 In the impact stress relief portions 123-1, 123-2, and 123-3 of the first to third modified examples shown, the ratio of the thickness T of the tube wall 123-1b, 123-2b, and 123-3b to the thickness t of the tube wall 111 of the valve body 11 is T=1t. Figure 8 In the impact stress relief portions 123-4 and 123-6 of the fourth and sixth modified examples shown, the ratio of the thickness T of the tube wall 123-4b and 123-6b to the thickness t of the tube wall 111 of the valve body 11 is also T=1t. On the other hand, in the impact stress relief portion 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 tube wall 123-5b to the thickness t of the tube wall 111 of the valve body 11 is T=0.5t. These ratios are also consistent with Figure 4 The impact stress alleviation portion 123 shown similarly satisfies the relationship of (Formula 3) described above.

[0063] And, in Figure 7 In the impact stress relief portion 123-1 of the first modified example (A), the ratio of the length L in the axial direction D11 to the thickness T of the tube wall 123-1b is L=0.5T. Figure 7 In the impact stress relief portion 123-2 of the second modification example (B), L=1T. Figure 7 In the impact stress mitigation portion 123-3 of the third modification example (C), L=2T. Figure 4 The impact stress mitigation portion 123 shown in FIG. 1 also satisfies the above relationship (Formula 1). Figure 8 In the impact stress relief portion 123-4 of the fourth modification example (A), L=2T. Figure 8 In the impact stress relief portion 123-5 of the fifth modification example (B), L=2.5T. Figure 8In the impact stress relief portion 123-6 of the sixth modified example (C), L=5T. These three ratios also satisfy the relationship of (Formula 1) above. Among them, if the ratio deviates from the relationship of (Formula 2) above and becomes L>5T, the enlargement of the cover part including the impact stress relief portion in the axial direction D11 becomes obvious. The relationship of L≤5T mentioned in (Formula 2) above becomes the upper limit regulation for suppressing the enlargement in the axial direction D11 of the impact stress relief portion.

[0064] In addition, Figure 4 The impact stress mitigation portion 123 and Figure 7 In any of the impact stress relief portions 123-1, 123-2, and 123-3 of the first to third modified examples shown in FIG. 1 , a small-diameter cylindrical protrusion 123c is provided as follows. Figure 4 implementation and Figure 7 The first to third variants are the same parts, so Figure 4 as well as Figure 7 The same symbol "123c" is marked in the figure.

[0065] The small-diameter cylindrical protrusion 123c is a portion that protrudes in a cylindrical shape from the inner circumference of the protruding end edge 123a of the impact stress relief portion 123, ..., 123-3 toward the opening 11a side of the valve body 11 along the axial direction D11. The diameter of the small-diameter cylindrical protrusion 123c is smaller than the outer diameter of the impact stress relief portion 123, ..., 123-3. On the other hand, at the opening end 11b of the valve body 11, a positioning recess 11c is provided at the inner circumference of the opening end 11b to position the cover member 12 when it is installed by fitting the above-mentioned small-diameter cylindrical protrusion 123c.

[0066] In the present embodiment and the first to third modified examples, the fixed portion of the valve body 11 and the cover member 12 is formed by welding as described above as the welded portion 16. The welded portion 16 is formed so that its weld depth Dp does not penetrate the small-diameter cylindrical protrusion 123c in the thickness direction D13.

[0067] In addition, Figure 8 In the impact stress alleviating portions 123-4, 123-5, and 123-6 of the fourth to sixth modified examples shown, unlike the above-described embodiment and the first to third modified examples, the following small-diameter recessed portions 123-4c, 123-5c, and 123-6c are provided.

[0068] The small diameter recessed portions 123-4c, 123-5c, 123-6c are recessed from the inner circumference of the protruding end edge 123a of the impact stress relieving portion 123-4, 123-5, 123-6 toward the stopper 122 side along the axial direction D11 to have a diameter smaller than the outer diameter of the impact stress relieving portion 123-4, 123-5, 123-6. On the other hand, at the opening end 11b of the valve body 11, at the inner circumference of the opening end 11b, positioning protrusions 11-4c, 11-5c, 11-6c are provided for positioning the cover member 12 when it is mounted by fitting into the small diameter recessed portions 123-4c, 123-5c, 123-6c.

[0069] In the fourth to sixth modified examples, the lengths of the small-diameter recesses 123-4c, 123-5c, and 123-6c in the axial direction D11 are different from each other. In addition, in the fifth modified example, the small-diameter recess 123-5c is formed in the axial direction D11 until it reaches the outer peripheral edge 122b of the stopper 122, that is, it covers the entire length of the impact stress relief portion 123-5. As a result, as described above, the impact stress relief portion 123-5 of the fifth modified example is thinned in such a manner that the ratio of the thickness T of the cylinder wall 123-5b to the thickness t of the cylinder wall 111 of the valve body 11 is T=0.5t. In the fourth and sixth modified examples, the positioning protrusions 11-4c, 11-5c, and 11-6c protrude by a length corresponding to the length of the small-diameter recesses 123-4c and 123-6c in the axial direction D11 into which the positioning protrusions 11-4c and 11-6c are to be embedded. In the fifth modification, the positioning protrusion 11-5c has a length substantially the same as that of the positioning protrusion 11-4c of the fourth modification, and is embedded in the small-diameter recess 123-5c until it is halfway close to the opening. In the fourth to sixth modifications, by providing such positioning protrusions 11-4c, 11-5c, and 11-6c on the valve body 11, the piston 221 stays on the inner side of the valve body 11 when it contacts the stopper 122, and the length L of the impact stress relief portions 123-4, 123-5, and 123-6 can be increased to 2T to 5T compared to the first to third modifications, thereby further relieving the stress generated in the welded portion 16 due to the impact when the piston 221 contacts the stopper 122.

[0070] In the fourth to sixth modified examples, the welded portion 16 as the fixing portion between the valve body 11 and the cover member 12 is formed so that the weld depth Dp does not penetrate the positioning protrusions 11-4c, 11-5c, and 11-6c in the thickness direction D13.

[0071] According to the above-described embodiment and the sliding switching valve 10 and the refrigeration cycle system 30 of the first to sixth modified examples, the following effects can be obtained. That is, in the present embodiment and the first to sixth modified examples, in the cover member 12, as an impact stress relieving unit for relieving the stress generated by the impact when the piston 221 abuts against the stopper 122, first, an impact stress relieving unit (1) (an impact stress relieving unit) is used.

[0072] The impact stress relief unit (1) (impact stress relief portion) is a unit in which an impact stress relief portion 123, ..., 123-6 is provided between the stopper 122 and the opening end 11b of the valve body 11, protruding from the outer peripheral edge 122b of the stopper 122 in the axial direction D11 and having its protruding edge 123a abutting against the opening end 11b of the valve body 11 and fixed to the opening end 11b. Thus, when the piston 221 abuts against the stopper 122 with a large collision load using an ultra-high pressure fluid in the refrigeration cycle system, the stopper 122 receives the collision load at a position away from the welded portion 16 of the valve body 11 and the cover member 12 to the outside in the axial direction D11 of the valve body 11. Therefore, the collision load is unlikely to act directly on the welded portion 16 as a stress that tends to separate the two, thereby improving the durability against the collision load when the piston 221 abuts against the stopper 122 of the cover member 12.

[0073] Next, the impact stress relieving means (2) (bending deformation) is a means that, for example, when the operating condition is a high-load operating condition, the pressure difference between the high and low pressures becomes large, and the collision load when the piston 221 abuts against the stopper 122 is too large, the stopper 122 is bent and deformed in the elastic region along the axial direction D11, and the impact stress relieving parts 123, ..., 123-6 are bent and deformed in the elastic region in the cross direction D12 relative to the axial direction D11, thereby relieving the stress generated in the welded portion 16 due to the impact when the piston 221 abuts. That is, in the impact stress relieving means (2) (bending deformation), the collision load when abutting is also unlikely to act as a stress that tends to separate the two on the welded portion 16 of the opening end 11b of the valve body 11 and the cover member 12. As a result, the durability against the collision load when the piston 221 abuts against the stopper 122 of the cover member 12 can be improved.

[0074] In this embodiment and the first to sixth modified examples, the impact stress relief portions 123, ..., 123-3 are formed so that the length L in the axial direction D11 and the thickness T of the cylinder wall 123b, ..., 123-3b satisfy the relationship of 0.5T≤L. According to this structure, the length L in the axial direction D11 of the impact stress relief portions 123, ..., 123-6 is sufficiently long, and the stopper 122 is arranged at a position sufficiently away from the welded portion 16 between the valve body 11 and the cover member 12 to the outside in the axial direction D11 of the valve body 11. With such an arrangement, the stress at the welded portion 16 can be more effectively relieved.

[0075] In addition, in the present embodiment and the first to sixth modified examples, the impact stress relieving portions 123, ..., 123-6 are further formed to satisfy the relationship of L ≤ 5T. According to this structure, stress can be effectively relieved, and the cover member 12 including the impact stress relieving portions 123, ..., 123-6, that is, the size of the slide-type switching valve 10 can be suppressed.

[0076] In addition, in the present embodiment and the first to third modified examples, the impact stress relieving portion 123, ..., 123-3 is provided with a small diameter cylindrical protrusion 123c, and the opening end 11b of the valve body 11 is provided with a positioning recess 11c. In addition, in the fourth to sixth modified examples, the impact stress relieving portion 123-4, 123-5, 123-6 is provided with a small diameter recess 123-4c, 123-5c, 123-6c, and the opening end 11b of the valve body 11 is provided with a positioning convex portion 11-4c, 11-5c, 11-6c. According to these structures, the cover part 12 is positioned at the opening 11a of the valve body 11 by embedding the small-diameter cylindrical protrusion 123c into the positioning recess 11c, or the positioning protrusions 11-4c, 11-5c, 11-6c into the small-diameter recesses 123-4c, 123-5c, 123-6c, so that the subsequent fixing operation can be carried out with good workability.

[0077] In addition, in the present embodiment and the first to sixth modified examples, the fixed portion of the valve body 11 and the cover member 12 is formed as a welded portion 16, and the welded portion 16 is formed with a welding depth Dp that does not penetrate the small-diameter cylindrical protrusion 123c or the positioning convex portions 11-4c, 11-5c, 11-6c in the thickness direction D13. According to this structure, the welded portion 16 as the fixed portion does not penetrate the small-diameter cylindrical protrusion 123c of the cover member 12 or the positioning convex portions 11-4c, 11-5c, 11-6c, so that splashes during welding can be effectively prevented from intruding into the interior of the valve body 11.

[0078] In addition, the above-described embodiments and the first to sixth modified examples are merely representative embodiments of the present invention, and the present invention is not limited thereto. That is, various modifications can be made within the scope of the present invention. Through such modifications, as long as the structure of the sliding switching valve and the refrigeration cycle system of the present invention is provided, it is of course also included in the scope of the present invention.

[0079] For example, in the above-mentioned embodiment and the first to sixth modified examples, as an example of a sliding switching valve, a sliding switching valve 10 as a four-way switching valve for switching the connection state of four pipes is illustrated, but the sliding switching valve is not limited to a four-way switching valve. As long as the sliding switching valve has at least one pair of pipes connected to the valve housing, it can also be a three-way switching valve for switching the pipes to be connected when a pair of pipes among three pipes is connected using a sliding valve core. Alternatively, it can also be a two-way switching valve that uses a sliding valve core to switch between two pipes. The number of pipes in the sliding switching valve, the method of switching the connection state, etc. can be appropriately set according to the application object of the sliding switching valve, etc.

[0080] In addition, in the above-mentioned embodiment and the first to sixth modified examples, as an example of a valve housing, the valve housing 1 in which the openings 11a at both ends of the cylindrical valve body 11 are blocked by the cover member 12 having the cover body portion 121 formed in a dome-shaped covered cylindrical shape is illustrated. However, the valve housing is not limited to this, and the valve body may be a cylindrical shape other than a cylinder, and the cover member may be any member as long as it blocks the opening of the valve body, and the cover body portion may be a covered cylindrical shape other than a dome-shaped covered cylinder.

[0081] In addition, in the above-mentioned embodiment and the first to sixth modified examples, as an example of an impact stress relieving portion, the impact stress relieving portion 123, ..., 123-6 in which the thickness T of the cylinder wall 123b and the thickness t of the cylinder wall 111 of the valve body 11 satisfy the relationship of 0.5t≤T≤1.5t are illustrated. However, the impact stress relieving portion is not limited to this, and can also be formed to deviate from this relationship. However, as described above, the relationship of 0.5t≤T≤1.5t is a preferred relationship in terms of the stress relieving effect at the welded portion 16. In addition, in the embodiment and the first to sixth modified examples, as specific examples satisfying this relationship, the impact stress relieving portion 123 with T=0.95t and the impact stress relieving portion 123-1, ..., 123-6 with T=1t are illustrated. However, the impact stress relieving portion when satisfying the relationship of 0.5t≤T≤1.5t is not limited to this, and as the thickness of the cylinder wall, any thickness that satisfies the above relationship can be adopted.

[0082] In addition, in the above-mentioned embodiment and the first to sixth modified examples, as an example of the impact stress relief portion, the impact stress relief portion 123, ..., 123-6 in which the length L of the axial direction D11 and the thickness T of the cylinder wall 123b, ..., 123-6b satisfy the relationship of 0.5T≤L is exemplified. However, the impact stress relief portion is not limited to this, and may be formed so that the length in the axial direction is 0.5T>L. However, according to the impact stress relief portion 123, ..., 123-6 formed so as to satisfy the relationship of 0.5T≤L, it is easy to bend and the stress at the welding part 16 can be relieved more effectively as described above. In addition, in the embodiment and the first to sixth modified examples, as specific examples satisfying this relationship, the impact stress relief portion 123 with L=1.2T and the impact stress relief portion 123-1, ..., 123-6 with L=0.5T, 1T, 2T, 2.5T, 5T are exemplified. However, the impact stress relaxation portion that satisfies the relationship of 0.5T≤L is not limited thereto, and any thickness that satisfies the above relationship may be adopted as the thickness of the tube wall.

[0083] In addition, in the above-mentioned embodiment and the first to sixth modified examples, as an example of the impact stress relief portion, in addition to the relationship of 0.5T≤L, the impact stress relief portion 123, ..., 123-6 that satisfies the relationship of L≤5T is exemplified. However, the impact stress relief portion is not limited to this, and may be formed to satisfy the relationship of 0.5T≤L, but L>5T. However, according to the impact stress relief portion 123, ..., 123-6 formed to satisfy the relationship of L≤5T, it is as described above that the size increase of the slide type switching valve 10 can be suppressed. In addition, in the embodiment and the first to sixth modified examples, as specific examples satisfying the relationship, the impact stress relief portion 123 of L=1.2T, and the impact stress relief portion 123-1, ..., 123-6 of L=0.5T, 1T, 2T, 2.5T, 5T are exemplified. However, the impact stress relief portion when satisfying the relationship of L≤5T is not limited to this, and as the thickness of the cylinder wall, any thickness that satisfies the above relationship can be adopted.

[0084] In addition, in the above-mentioned embodiment and the first to sixth modified examples, as examples of each of the impact stress relieving portion and the valve body, the impact stress relieving portion 123, ..., 123-6 provided with the small-diameter cylindrical protrusion 123c or the small-diameter recessed portion 123-4c, 123-5c, 123-6c and the valve body 11 provided with the positioning recessed portion 11c or the positioning convex portion 11-4c, 11-5c, 11-6c are exemplified. However, the impact stress relieving portion and the valve body are not limited to these, and the small-diameter cylindrical protrusion, the small-diameter recessed portion, the positioning recessed portion, and the positioning convex portion may not be provided. However, by providing the impact stress relief portion 123, ..., 123-6 and the valve body 11 with a small-diameter cylindrical protrusion 123c, small-diameter recesses 123-4c, 123-5c, 123-6c, a positioning recess 11c, and positioning protrusions 11-4c, 11-5c, and 11-6c, the cover part 12 can be fixed to the opening 11a of the valve body 11 with good operability as described above.

[0085] In addition, in the above-mentioned embodiment and the first to third modified examples, as an example of a valve housing, the valve housing 1 is illustrated in which the valve body 11 and the cover member 12 are fixed by forming a weld portion 16 with a welding depth Dp that does not penetrate the small-diameter cylindrical protrusion 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 weld portion formed with a welding depth that penetrates the small-diameter cylindrical protrusion and the positioning protrusion. However, as described above, by forming the weld portion 16 with a welding depth Dp that does not penetrate the small-diameter cylindrical protrusion 123c and the positioning protrusions 11-4c, 11-5c, 11-6c, it is possible to effectively prevent spatter from intruding into the interior of the valve body 11 during welding.

Claims

1. A sliding switching valve, characterized in that: have: The valve housing is cylindrical and has openings at both ends of the valve body connected to at least a pair of pipes on its peripheral wall, each of which is blocked by a cover member; a valve element which is provided inside the valve body so as to be slidable in the axial direction of the valve body and switches the communication state of the pipe; and The sliding mechanism is a mechanism portion extending in the axial direction inside the valve body and having pistons at both ends, the valve core is connected to the middle portion thereof, and the valve core slides due to the axial sliding driving force received by the piston. The cover member comprises: a cover body portion formed in a covered cylindrical shape having an inner diameter smaller than the inner diameter of the opening of the valve body, and arranged outside the opening of the valve body in the axial direction in such a manner that the cylinder opening faces the opening of the valve body; a stopper portion extending from the opening edge of the cylinder opening of the cover body toward the outside of the cover body in a flange shape having an outer diameter larger than the inner diameter of the opening of the valve body, and abutting and stopping the piston on one end side of the sliding mechanism that slides through the opening in the axial direction on a surface facing the opening side; as well as an impact stress relief unit for relieving stress generated by an impact when the piston abuts against the stopper, The impact stress relief unit is a unit that relieves the stress by providing an impact stress relief portion between the stop portion and the open end of the opening surrounding the valve body. The impact stress relief portion protrudes in a cylindrical shape along the axial direction from the outer peripheral edge of the stop portion, and its protruding end edge abuts against the open end of the valve body and is fixed to the open end.

2. The sliding switching valve according to claim 1, characterized in that: The impact stress relieving unit is provided with the impact stress relieving portion, and further becomes the following unit: due to the impact when the stopper abuts against the piston, the stopper is bent and deformed in the axial direction, and the impact stress relieving portion is bent and deformed in a direction intersecting the axial direction, thereby relieving the stress.

3. The sliding switching valve according to claim 1, characterized in that: The cylindrical impact stress alleviating portion is formed to satisfy the relationship of 0.5T≤L, where L is the length in the axial direction and T is the thickness of the cylindrical wall.

4. The sliding switching valve according to claim 3, characterized in that: The impact stress alleviating portion is also formed to satisfy the relationship of L≤5T.

5. The sliding switching valve according to claim 1, characterized in that: The impact stress relief portion is provided with a small-diameter cylindrical protrusion or a small-diameter recess, the small-diameter cylindrical protrusion protrudes from a position close to the inner periphery of the protruding end edge along the axial direction toward the opening side of the valve body in a cylindrical shape with a diameter smaller than the outer diameter of the impact stress relief portion, and the small-diameter recess is recessed from a position close to the inner periphery of the protruding end edge along the axial direction toward the stop portion side with a diameter smaller than the outer diameter of the impact stress relief portion, At the opening end of the valve body, a positioning recess is provided at an inner circumferential position of the opening end for positioning the cover component during installation by embedding the small-diameter cylindrical protrusion of the impact stress relief portion, or a positioning protrusion is provided at an inner circumferential position of the opening end for positioning the cover component during installation by embedding the small-diameter recess of the impact stress relief portion.

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

7. A refrigeration cycle system, characterized in that: have: a compressor that compresses a refrigerant as a fluid; a first heat exchanger that functions as a condenser in a cooling mode; and a second heat exchanger that functions as an evaporator in a cooling mode; An expansion unit that expands and decompresses refrigerant between the first heat exchanger and the second heat exchanger; and the slide-type switching valve according to any one of claims 1 to 6.

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