Expansion valve

Abstract

To obtain a configuration in which a small amount of fluid flows through a valve hole even in a closed state, without forming a recess part in a valve seat by pressing a tool against the valve seat.SOLUTION: An expansion valve comprises: a valve body having an inlet part, a valve chamber into which fluid flows via the inlet part, and a valve hole through which fluid flows out of the valve chamber; a valve element that is arranged in the valve chamber, and adjusts a flow rate of fluid through the valve hole by moving closer to and away from the valve hole; and a gap forming member that is integrated with the valve body or the valve element, is sandwiched between the valve element and the inner surface of the valve chamber when the valve element approaches the valve hole, and in the sandwiched state, forms a gap between the valve element and the inner surface of the valve chamber that constitutes a part of the flow path through which the inlet part side of the valve chamber and the valve hole communicate with each other.SELECTED DRAWING: Figure 4

Description

【Technical Field】 【0001】 The present disclosure relates to an expansion valve. 【Background Art】 【0002】 An expansion valve is used in a refrigerant circulation system. The expansion valve includes a valve body having a valve chamber and a valve seat into which a high-pressure refrigerant flows, a valve element disposed in the valve chamber and configured to adjust the flow rate of the refrigerant by approaching and separating from the valve seat (see, for example, Patent Document 1). There is also known an expansion valve that can allow a small amount of refrigerant to flow into the refrigerant circulation system even in a closed state. As this type of expansion valve, there is an expansion valve in which a concave portion is formed in the valve seat by pressing a tool having a convex portion against the valve seat. Even when the valve element is seated on the valve seat, a small amount of refrigerant can flow through the concave portion into the valve hole. 【Prior Art Documents】 【Patent Documents】 【0003】 【Patent Document 1】 Japanese Unexamined Patent Application Publication No. 2023-71 【Summary of the Invention】 【Problems to be Solved by the Invention】 【0004】 As described above, in an expansion valve in which a concave portion is formed in the valve seat by pressing a tool having a convex portion against the valve seat, a load is applied to the valve body when the tool is pressed. The load may cause deformation in a portion of the valve body different from the valve seat. In order to suppress this deformation to a level that does not cause a problem with the expansion valve, there have been restrictions on the depth and width of the concave portion. 【0005】 An object of the present disclosure is to obtain a configuration in which a small amount of fluid can flow through the valve hole even when the valve element closes the valve hole, without forming a concave portion in the valve seat by pressing a tool against the valve seat. 【Means for Solving the Problems】 【0006】 The expansion valve according to the first embodiment is characterized by comprising: a valve body having an inlet, a valve chamber through which fluid flows in via the inlet, and a valve hole through which the fluid flowing out of the valve chamber flows; a valve element disposed in the valve chamber and adjusting the flow rate of the fluid flowing through the valve hole by moving closer to or further away from the valve hole; and a gap-forming member integrated with the valve body or the valve element, which is sandwiched between the valve element and the inner surface of the valve chamber when the valve element approaches the valve hole, and in this sandwiched state, forms a gap between the valve element and the inner surface of the valve chamber that constitutes a part of a flow path connecting the inlet side of the valve chamber and the valve hole. 【0007】 In the above configuration, high-pressure fluid flows into the valve chamber from the inlet of the valve body, and the fluid that has entered the valve chamber flows out of the valve chamber and through the valve hole. The valve body adjusts the flow rate of the fluid flowing through the valve hole by moving closer to or further away from the valve hole. 【0008】 Here, the gap-forming member is sandwiched between the inner surfaces of the valve body and the valve chamber. In this sandwiched state, a gap is formed between the inner surfaces of the valve body and the valve chamber, forming a part of the flow path that connects the inlet side of the valve chamber to the valve hole. As a result, when the valve body closes the valve hole, a small amount of fluid passes through this gap, allowing a small amount of fluid to flow through the valve hole. 【0009】 In this way, by pressing the tool against the valve seat, it is possible to obtain a configuration in which a small amount of fluid flows through the valve opening even when the valve body is closed, without forming a recess on the valve seat. 【0010】 The expansion valve according to the second embodiment is characterized in that, in the expansion valve according to the first embodiment, the gap-forming member has a plurality of clamped portions that are sandwiched between the inner surface of the valve chamber and the valve body, with gaps between them in the circumferential direction of the valve hole. 【0011】 In the above configuration, the gap-forming member has multiple clamped portions that are sandwiched between the inner surface of the valve chamber and the valve body, spaced apart in the circumferential direction of the valve hole. In this way, even when the valve body closes the valve hole, fluid can pass through the multiple gaps formed at intervals in the circumferential direction of the valve hole. 【0012】 The expansion valve according to the third embodiment is characterized in that, in the expansion valve according to the second embodiment, the valve hole is cylindrical in shape with the valve body extending in an approach-to-across direction toward and toward the valve hole, and the gap-forming member is arranged at intervals in the circumferential direction of the valve hole and has a plurality of extended portions including the clamped portion, which extend in the radial direction of the valve hole when viewed from the approach-to-across direction. 【0013】 In the above configuration, the gap-forming member is arranged at intervals in the circumferential direction of the valve hole and has multiple extended portions that extend radially around the valve hole when viewed from the approach-to-approach direction and include a clamped portion. As a result, the gap is defined by a pair of adjacent extended portions and the inner surface of the valve chamber, and when viewed from the approach-to-approach direction, the portion extends radially around the valve hole. Therefore, the flow resistance in the gap can be reduced compared to the case where the gap extends spirally around the valve hole when viewed from above. 【0014】 The expansion valve according to the fourth embodiment is characterized in that, in the expansion valve according to the first embodiment, the gap forming member has a mounting portion that is fitted into the valve hole. 【0015】 In the above configuration, the gap-forming member is attached to the valve body by fitting its mounting portion into the valve hole. In this way, the gap-forming member can be attached to the valve body without providing a dedicated mounting member. 【0016】 The expansion valve according to the fifth embodiment is characterized in that, in the expansion valve according to the fourth embodiment, the mounting portion has a protruding portion that protrudes downstream from the outlet of the valve hole in the direction of fluid flow, and the protruding portion is formed in the shape of a cylindrical shape that is continuous around the axis of the valve hole, or in the shape that has both ends in the circumferential direction of the axis and the ends are separated from each other. 【0017】 In the above configuration, the protruding portion of the mounting portion protrudes from the outlet of the valve hole. As a result, the fluid flowing through the valve hole flows along the protruding portion and is discharged. Therefore, compared with the case where the entire mounting portion is within the valve hole, the rectifying effect on the refrigerant flowing through the valve hole can be improved. 【0018】 The expansion valve according to the sixth aspect is the expansion valve according to any one of the first to third aspects, and includes a biasing member that biases the valve body toward the inner surface of the valve chamber, and a rod-shaped member that is inserted into the valve hole and is disposed on the opposite side of the biasing member with the valve body interposed therebetween, and moves the valve body against the biasing force of the biasing member to separate the valve body from the valve hole. The gap forming member has a base portion sandwiched between the valve body and the valve rod. 【0019】 In the above configuration, the base portion of the gap forming member is sandwiched between the valve body and the valve rod. Therefore, the gap forming member can be attached to the valve body without providing a dedicated attachment member. 【Effects of the Invention】 【0020】 According to the present disclosure, a configuration in which a small amount of fluid flows through the valve hole even when the valve body closes the valve hole can be obtained without forming a recess in the valve seat by pressing a tool against the valve seat. 【Brief Description of the Drawings】 【0021】 [Figure 1] It is a cross-sectional view showing a schematic configuration of an expansion valve according to a first embodiment of the present disclosure. [Figure 2] It is a perspective view showing an expansion valve according to a first embodiment of the present disclosure. [Figure 3] It is an exploded perspective view showing a spacer and a valve body used in an expansion valve according to a first embodiment of the present disclosure. [Figure 4] (A)(B) It is a cross-sectional view showing a state where the valve body closes the valve hole and a state where the valve body opens the valve hole in an expansion valve according to a first embodiment of the present disclosure. [Figure 5](A)(B) An enlarged cross-sectional view showing a portion through which refrigerant can pass and a portion through which refrigerant cannot pass in a state where the valve body closes the valve hole, of an expansion valve according to the first embodiment of the present disclosure. [Figure 6] (A)(B) A perspective view showing a face portion etc. of an expansion valve according to a comparative form with respect to the first embodiment of the present disclosure. [Figure 7] (A)(B) A process diagram showing a process of forming a concave portion in a face portion etc. of an expansion valve according to a comparative form with respect to the first embodiment of the present disclosure. [Figure 8] An exploded perspective view showing a spacer and a valve body used in an expansion valve according to the second embodiment of the present disclosure. [Figure 9] (A)(B) Cross-sectional views showing a state where the valve body closes the valve hole and a state where the valve body opens the valve hole, of an expansion valve according to the second embodiment of the present disclosure. [Figure 10] (A)(B) An enlarged cross-sectional view showing a portion through which refrigerant can pass and a portion through which refrigerant cannot pass in a state where the valve body closes the valve hole, of an expansion valve according to the second embodiment of the present disclosure. [Figure 11] An exploded perspective view showing a spacer and a valve body used in an expansion valve according to the third embodiment of the present disclosure. [Figure 12] (A)(B) Cross-sectional views showing a state where the valve body closes the valve hole and a state where the valve body opens the valve hole, of an expansion valve according to the third embodiment of the present disclosure. [Figure 13] (A)(B) An enlarged cross-sectional view showing a portion through which refrigerant can pass and a portion through which refrigerant cannot pass in a state where the valve body closes the valve hole, of an expansion valve according to the third embodiment of the present disclosure. 【Mode for Carrying Out the Invention】 【0022】 <First Embodiment> An example of an expansion valve according to the first embodiment of the present disclosure will be described with reference to FIGS. 1 to 7. In the figures, the arrow H indicates the vertical direction of the device, the arrow W indicates the width direction of the device, and the arrow D indicates the depth direction of the device. Furthermore, in this first embodiment, the vertical direction of the device is the direction in which the valve body 12 and the power element 70, as shown in Figure 1 and described later, are aligned, with the side on which the power element 70 is located being considered upward. The width direction of the device is the direction perpendicular to the vertical direction of the device and along the return flow path 30. The depth direction of the device is the direction perpendicular to both the vertical direction and the width direction of the device. 【0023】 As shown in Figure 1, the expansion valve 10 according to this embodiment is used, for example, in a refrigerant circulation system 200 and is connected to a compressor 201, a condenser 202, and an evaporator 204. 【0024】 (Configuration of expansion valve 10) As shown in Figure 1, the expansion valve 10 comprises a valve body 12, a power element 70, a valve element 40, a spacer 50, a valve stem 60, a support member 100, a coil spring 44, and an adjustment screw 120. 【0025】 [Valve body 12] The valve body 12 is made of metal, and more specifically, an aluminum alloy. It is formed by extruding an aluminum alloy with the device width direction shown in Figure 1 as the extrusion direction, and then machining the extruded member (see Figure 2). Extrusion molding is just one example, and the valve body 12 may be formed by other molding methods. 【0026】 As shown in Figure 1, the valve body 12 has a power element mounting portion 14 formed at the upper end of the valve body 12 and a female thread 12a formed at the lower end of the valve body 12. 【0027】 Furthermore, the valve body 12 has an inlet port 20 formed in the lower part of the valve body 12, with one side in the device width direction (right side in the figure) open, through which high-pressure liquid refrigerant flows in, and a valve chamber 24 formed on the other side in the device width direction relative to the inlet port 20, and in the central part of the valve body 12 in the device width direction. The valve body 12 also has a valve hole 26 with a circular cross-section extending from the valve chamber 24 in the vertical direction of the device, and an outlet port 28 formed above the valve hole 26, with the other side in the device width direction (left side in the figure) open, through which the liquid refrigerant flowing in from the inlet port 20 flows through the valve hole 26, undergoes adiabatic expansion, and flows out as gaseous refrigerant. Refrigerant is an example of a fluid. 【0028】 Furthermore, the valve body 12 has a gaseous refrigerant return passage 30 formed above the outlet port 28 and open on both sides in the device width direction, and a circular cross-section through hole 34 extending vertically from the outlet port 28 to the return passage 30. This through hole 34 is formed in the central part of the valve body 12 in the device width direction, and the upper part of the through hole 34 is a large-diameter portion 34a. 【0029】 Furthermore, the valve body 12 is positioned above the inlet port 20 and below the return passage 30, and has a mounting hole 80 for attaching the expansion valve 10 to an evaporator or other components (not shown). 【0030】 -Power element mounting section 14- As shown in Figure 1, the power element mounting portion 14 is formed at the upper end of the valve body 12. Specifically, the power element mounting portion 14 is a circular hole that opens upward in a circular shape, has an internal thread 14a on its inner circumference, and has a bottom surface. A circular communication port 32 that communicates with the return passage 30 is formed in the center of this bottom surface. The communication port 32 is formed in the central part of the valve body 12 in the device width direction, and the central axis of the communication port 32 coincides with the central axis of the power element mounting portion 14. 【0031】 -Female thread 12a, valve chamber 24- As shown in Figure 1, the female thread 12a is formed on the inner surface of a circular opening that opens to the lower surface of the valve body 12. The valve chamber 24 is formed above the male thread 12a. Furthermore, when the adjustment screw 120 is screwed into the male thread 12a, the opening on the lower surface of the valve body 12 is closed. 【0032】 Furthermore, the valve chamber 24 has a circular cross-section that extends vertically, and the central axis of the valve chamber 24 that extends vertically coincides with the central axis of the communication port 32 that extends vertically. 【0033】 -Inlet port 20, outlet port 28, valve hole 26- As shown in Figure 1, the inlet port 20 opens on one side in the width direction of the device, and a reduced-diameter inlet portion 20a is formed on the other side of the inlet port 20 in the width direction of the device for communication with the valve chamber 24. 【0034】 The outlet port 28 is located above the inlet port 20 and opens to the other side in the device width direction. A reduced-diameter portion 28a is formed on one side of the outlet port 28 in the device width direction. A valve chamber 24 is formed below this reduced-diameter portion 28a, and the reduced-diameter portion 28a and the valve chamber 24 are in communication through a valve hole 26. 【0035】 The valve bore 26 has a circular cross-section that extends vertically in the device, and the central axis of the valve bore 26 extending vertically coincides with the central axis of the valve chamber 24 extending vertically. Furthermore, a conical surface portion 24a is formed on the top surface of the valve chamber 24 on the valve bore 26 side. The surface portion 24a is an example of an inner surface. 【0036】 -Return channel 30, through hole 34- As shown in Figure 1, the return channel 30 is formed above the outlet port 28 and is open on both sides in the width direction of the device. The return channel 30 communicates with the small diameter portion 28a of the outlet port 28 via a through hole 34 that extends in the vertical direction. 【0037】 The through-hole 34 has a circular cross-section that extends vertically, and the central axis of the through-hole 34 that extends vertically coincides with the central axis of the valve chamber 24 that extends vertically. In addition, the upper portion of the through-hole 34 is a large-diameter section 34a. 【0038】 [Power Element 70] As shown in Figure 1, the power element 70 includes a top cover member 72 made of metal, and in one example, stainless steel. Furthermore, the power element 70 includes a receiving member 74 with a central portion opening downward, and a diaphragm 76 sandwiched between the top cover member 72 and the receiving member 74. Furthermore, the power element 70 includes a stopper member 90 positioned so that its upper surface contacts the lower surface of the diaphragm 76. 【0039】 Furthermore, a pressure-operated chamber 78 is formed between the upper cover member 72 and the diaphragm 76, and this pressure-operated chamber 78 is filled with operating gas through a hole formed in the upper cover member 72. A sealing plug 66 for sealing the pressure-operated chamber 78 is attached to the hole in the upper cover member 72. 【0040】 Furthermore, the lower portion of the receiving member 74 is cylindrical in shape, extending in the vertical direction, and a male thread 74a is formed on the cylindrical outer surface. The power element 70 is attached to the valve body 12 by screwing this male thread 74a into a female thread 14a formed on the power element mounting portion 14 of the valve body 12. 【0041】 [Valve body 40, spacer 50, valve stem 60] As shown in Figure 1, the valve body 40 is spherical and positioned in the valve chamber 24, facing the valve hole 26 in the vertical direction of the device. 【0042】 The spacer 50 is made of metal, for example, stainless steel, and is positioned between the valve body 40 and the surface 24a of the valve chamber 24, as shown in Figure 4(A). The spacer 50 is an example of a gap-forming member. The spacer 50 will be described in detail later. 【0043】 Furthermore, as shown in Figure 1, the valve stem 60 is a cylindrical rod extending in the vertical direction of the device and is inserted into the valve hole 26, through hole 34, and communication port 32 of the valve body 12. The upper end of the valve stem 60 is inserted into a concave receiving portion 90a formed on the lower surface of the stopper member 90, and the lower end of the valve stem 60 is in contact with the upper surface of the valve body 40. In addition, an annular sealing member 36 is positioned in contact with the valve stem 60 and the circumferential surface of the large diameter portion 34a of the through hole 34. 【0044】 [Support member 100] As shown in Figure 1, the support member 100 is positioned in the valve chamber 24 and supports the valve body 40 from below. Specifically, the support member 100 has a cylindrical main body portion 100a extending in the vertical direction, a flange portion 100b projecting radially from the upper part of the main body portion 100a, and a recess 100c formed on the upper surface of the main body portion 100a. The valve body 40 is placed in the recess 100c. 【0045】 [Adjustment screw 120] As shown in Figure 1, the adjustment screw 120 is located at the lower end of the valve body 12 and comprises a main body portion 120a, a hexagonal socket 120b, an insertion portion 120c, a tip portion 120d, and a recess 120e. 【0046】 The outer shapes of the main body 120a, insertion portion 120c, and tip portion 120d are circular when viewed from above. The insertion portion 120c is provided on the upper part of the main body 120a with a smaller diameter than the main body 120a, and the tip portion 120d is provided on the upper part of the insertion portion 120c with a smaller diameter than the insertion portion 120c. Furthermore, a male thread 122 is formed on the outer circumference of the main body 12a, which is screwed into a female thread 12a formed on the valve body 12. 【0047】 The recess 120e has a circular cross-section with an open top. The hexagonal hole 120b is formed on the lower surface of the adjustment screw 120, and by inserting a hexagonal wrench into the hexagonal hole 120b and operating the hexagonal wrench to turn the adjustment screw 120, the male screw 122 is screwed into the female screw 12a of the valve body 12. 【0048】 Furthermore, an O-ring 118 is positioned between the outer circumferential surface of the tip portion 120d and the inner circumferential surface of the valve chamber 24. 【0049】 [Coil spring 44] As shown in Figure 1, the coil spring 44 is positioned on the opposite side of the valve stem 60 with the valve body 40 in between, and extends vertically in the device between the lower surface of the flange portion 100b formed on the support member 100 and the bottom surface of the internal space of the recess 120e formed on the adjustment screw 120. The coil spring 44 is in a compressed state. The elastic force of the coil spring 44 biases the valve body 40 toward the valve hole 26 via the support member 100. The coil spring 44 is an example of a biasing member. 【0050】 (Operation of expansion valve 10) Next, the operation of the expansion valve 10 will be explained. When the refrigerant is pressurized by the compressor 201, it is liquefied in the condenser 202 and sent to the expansion valve 10. The liquid refrigerant sent from the condenser 202 flows into the valve chamber 24 through the inlet portion 20a of the inlet port 20 of the expansion valve 10. When the valve is open, the liquid refrigerant that has flowed into the valve chamber 24 flows through the valve hole 26, undergoes adiabatic expansion, and flows into the outlet port 28. Through expansion, the liquid refrigerant becomes a gaseous refrigerant and is sent to the evaporator 204. In this embodiment, the open state is when the valve body 40 is separated from the spacer 50. 【0051】 The gaseous refrigerant sent to the evaporator 204 undergoes heat exchange with the surrounding air in the evaporator 204. The gaseous refrigerant that has undergone heat exchange in the evaporator 204 flows through the return passage 30 of the expansion valve 10 and is returned to the compressor 201. 【0052】 Here, the heat from the gaseous refrigerant flowing through the return channel 30 is transferred to the working gas filling the pressure working chamber 78 via the valve stem 60, the stopper member 90, and the diaphragm 76. As the volume of the working gas changes due to the amount of heat transferred, the gas pressure of the working gas acts on the upper surface of the diaphragm 76. 【0053】 The diaphragm 76 moves vertically in accordance with the difference between the gas pressure acting on its upper surface and the force acting on its lower surface. 【0054】 The vertical movement of the diaphragm 76 is transmitted to the valve body 40 via the stopper member 90 and the valve stem 60. As the valve body 40 moves vertically, it moves closer to and further away from the valve hole 26. In this way, the flow rate of the refrigerant sent from the expansion valve 10 to the evaporator 204 is adjusted. 【0055】 (Main part configuration) Next, the spacer 50, which is the main part of this embodiment, will be described in comparison with the expansion valve 510 of the comparative embodiment. The expansion valve 510 of the comparative embodiment will be described primarily for its differences from the expansion valve 10 of this embodiment. 【0056】 [Comparative form of expansion valve 510] The expansion valve 510 does not have a spacer 50. As shown in Figure 6(A), the surface 524a of the expansion valve 510 has multiple recesses 526, which are V-shaped V-notches in cross-section, extending radially from the valve hole 26. The surface 524a includes the valve seat. Part of the recesses 526 are formed in the valve seat. 【0057】 These multiple recesses 526 are formed by pressing a notch-forming jig 530, which has multiple V-shaped protrusions 530a, onto a cone-shaped surface 524a, as shown in Figures 7(A) and 7(B). The depth of the recesses 526 can be changed by the amount the notch-forming jig 530 is pressed in. The notch-forming jig 530 is an example of a pressing jig. 【0058】 Here, by pressing the notch-forming jig 530 into the inlet of the valve hole 26, a convex deformation 550 is created on the circumferential surface of the small-diameter portion 28a (see Figure 1) of the outlet port 28, as shown in Figure 6(B). 【0059】 In the above configuration, even when the valve body 40 of the expansion valve 510 closes the valve hole 26, a small amount of refrigerant passes through the recess 526, causing a small amount of refrigerant to circulate in the flow path of the refrigerant circulation system. For example, by including a lubricant in the refrigerant, the lubricant circulates in the flow path even when the valve body 40 closes the valve hole 26. This supplies lubricant to each device. 【0060】 [Surface portion 24a and spacer 50 in this embodiment] In this embodiment, the surface 24a of the valve chamber 24 is conical in shape, and no recesses are formed. In other words, the valve body 12 does not undergo deformation that would result from the formation of recesses. 【0061】 In this embodiment, the spacer 50 is made of metal, for example, stainless steel, and has a thickness of 0.05 mm. The thickness of the spacer 50 is just an example and may be other thicknesses. 【0062】 Figure 3 shows an exploded perspective view of the valve body 40 and the spacer 50. As shown in Figure 3, the spacer 50 has an annular portion 52 and an extended portion 54 that rises upward from the edge of the annular portion 52. The annular portion 52 is formed to follow the conical surface of the conical surface portion 24a. 【0063】 Three extensions 54 are provided around the valve hole 26 (see Figure 1) at similar intervals. The extensions 54 extend radially around the valve hole 26 when viewed from above. Here, "interval" refers to the pitch, which is the distance around the valve hole 26 from the center of one extension 54 to the center of the adjacent extension 54. "Similar" means that the interval of one extension is within ±10% of the interval of the others. Note that the number of extensions 54 is not limited to three; other numbers may also be provided. 【0064】 The extension portion 54 consists of a base portion 54a that follows the conical surface of the conical surface portion 24a, and a tip portion 54b with a circular arc cross-section that follows the inner circumferential surface 26a of the valve hole 26 (see Figure 4(A)). The tip portion 54b of the extension portion 54 is pressed against the inner circumferential surface 26a of the valve hole 26 by the biasing force generated by the elastic deformation of the spacer 50, and is attached. In this way, the spacer 50 is attached to the expansion valve 10. The tip portion 54b is an example of an attachment portion. 【0065】 In the above configuration, as shown in Figures 4(A) and 4(B), the valve body 40 moves upward and comes into contact with the spacer 50, and the extended portion 54 of the spacer 50 is sandwiched between the surface portion 24a of the valve chamber 24 and the valve body 40 (see Figure 4(A)). The valve body 40 moves downward and separates from the spacer 50 (see Figure 4(B)). The vertical direction of the device is an example of the contact and separation direction. Here, in this embodiment, the portion of the extended portion 54 that is sandwiched between the surface portion 24a and the valve body 40 is referred to as the sandwiched portion. 【0066】 Specifically, when the valve body 40 closes the valve hole 26, the base 54a of the extension 54 of the spacer 50 is sandwiched between the valve body 40 and the surface 24a of the valve chamber 24, as shown in Figure 5(B). In other words, the valve body 40 and the surface 24a of the valve chamber 24 are in a non-contact state. As a result, between adjacent extensions 54, as shown in Figure 5(A), a gap 56 is formed between the valve body 40 and the surface 24a through which the refrigerant can pass when the valve is closed. In other words, when the valve body 40, which has moved toward the surface 24a, is immobilized in the closed state, the base 54a of the extension 54 of the spacer 50 is sandwiched between the valve body 40 and the surface 24a of the valve chamber 24, thereby forming a gap 56 between the valve body 40 and the surface 24a. The gap 56 communicates with the inside of the valve chamber 24 and the inside of the valve hole 26. 【0067】 As a result, even when the valve body 40 is closed to the valve hole 26, that is, when the spacer 50 is sandwiched between the valve body 40 and the surface 24a of the valve chamber 24, a small amount of refrigerant flows through the gap 56, causing a small amount of refrigerant to circulate in the flow path of the refrigerant circulation system. For example, if the refrigerant contains a lubricant, the lubricant will circulate in the flow path even when the valve body 40 is closed to the valve hole 26. This ensures that lubricant is supplied to each device. 【0068】 Here, the state in which the valve body 40 closes the valve hole 26 is the state in which the valve body 40, having moved toward the valve hole 26, comes into contact with the spacer 50 and becomes unable to move. 【0069】 (summary) As explained above, in the expansion valve 10, when the valve is closed, the base 54a of the extended portion 54 of the spacer 50 is sandwiched between the valve body 40 and the surface 24a of the valve chamber 24, thereby forming a gap 56 between the valve body 40 and the surface 24a of the valve chamber 24. As a result, in the expansion valve 10, unlike the expansion valve 510, a recess 526 can be formed on the surface 524a by pressing the notch forming jig 530 against the inlet of the valve hole 26, and a configuration can be obtained in which a small amount of refrigerant passes through the valve hole 26 even when the valve body 40 is closed. 【0070】 Furthermore, in the expansion valve 10, unlike the expansion valve 510, the notch forming jig 530 is not pressed against the inlet of the valve hole 26. Therefore, deformation of the valve body 12 caused by pressing the notch forming jig 530 against the inlet of the valve hole 26 can be suppressed. 【0071】 Furthermore, in the expansion valve 10, the extended portion 54 of the spacer 50 is arranged at intervals in the circumferential direction of the valve hole 26, and when viewed from above, it extends radially around the valve hole 26. The gap 56 is part of a groove defined by a pair of adjacent extended portions 54 and the surface portion 24a of the valve chamber 24. When viewed from above, this groove extends radially around the valve hole 26. Therefore, the flow resistance generated in the gap 56 can be reduced compared to the case where this groove extends spirally around the valve hole when viewed from above. 【0072】 Furthermore, in the expansion valve 10, the spacer 50 is attached to the valve body 12 by mounting the arc-shaped tip portion 54b to the inner circumferential surface of the valve hole 26. This allows the spacer 50 to be attached to the valve body 12 without the need for a dedicated mounting member. 【0073】 <Second Embodiment> An example of an expansion valve according to the second embodiment of this disclosure will be described with reference to Figures 8 to 10. The second embodiment will primarily describe the differences from the first embodiment. 【0074】 (composition) Figure 8 shows an exploded perspective view of the valve body 40 and spacer 250 in the expansion valve 210 of the second embodiment. In this embodiment, the spacer 250 is made of metal, for example, stainless steel, and has a thickness of 0.05 mm. The thickness of the spacer 250 is just an example and may be other thicknesses. The spacer 250 is an example of a gap-forming member. 【0075】 As shown in Figure 8, the spacer 250 has a cylindrical portion 252 and an extended portion 254 extending downward from the lower edge of the cylindrical portion 252. The cylindrical portion 252 has a circular cross-section and is fitted into the valve hole 26 as shown in Figures 9(A) and 9(B). The upper part of the cylindrical portion 252 has a protruding portion 252a that protrudes upward from the outlet of the valve hole 26. Specifically, the cylindrical portion 252 is fitted into the valve hole 26 and mounted on the inner circumferential surface 26a of the valve hole 26. In this way, the spacer 250 is attached to the valve body 12. The cylindrical portion 252 is an example of a mounting portion. The protruding portion 252a is not limited to a cylindrical shape and may have a shape in which a part is spaced apart in the circumferential direction of the valve hole 26, etc. 【0076】 As shown in Figure 8, three extensions 254 are provided around the valve hole 26 at similar intervals. When viewed from above, the extensions 254 extend radially around the valve hole 26 and are formed to follow the conical surface of the conical surface portion 24a. Note that the number of extensions 254 is not limited to three, and other numbers may be used. 【0077】 In the above configuration, as shown in Figures 9(A) and 9(B), the valve body 40 moves upward and comes into contact with the spacer 250, and the spacer 250 is sandwiched between the surface 24a of the valve chamber 24 and the valve body 40 (see Figure 9(A)). The valve body 40 moves downward and separates from the spacer 250 (see Figure 9(B)). 【0078】 Specifically, when the valve body 40 closes the valve hole 26, the extended portion 254 of the spacer 250 is sandwiched between the valve body 40 and the surface 24a of the valve chamber 24, as shown in Figure 10(B). In other words, the valve body 40 and the surface 24a of the valve chamber 24 are in a non-contact state. As a result, between adjacent extended portions 254, as shown in Figure 10(A), a gap 256 is formed between the valve body 40 and the surface 24a, through which the refrigerant can pass. In other words, in the closed valve state, when the valve body 40, which has moved toward the surface 24a, is immobilized, the extended portion 254 of the spacer 250 is sandwiched between the valve body 40 and the surface 24a of the valve chamber 24, thereby forming a gap 256 between the valve body 40 and the surface 24a. The gap 256 communicates with the inside of the valve chamber 24 and the inside of the valve hole 26. For example, if the refrigerant contains a lubricant, the lubricant circulates through the flow path even when the valve body 40 is closed to the valve hole 26. This ensures that the lubricant is supplied to each device. 【0079】 (summary) As explained above, in the expansion valve 210, the upper portion of the cylindrical part 252 of the spacer 250 has a protruding portion 252a that protrudes upward (downstream in the direction of refrigerant flow) from the outlet of the valve hole 26. As a result, the refrigerant flowing through the valve hole 26 flows along the protruding portion 252a and is discharged. Therefore, compared to the case where the cylindrical part is contained within the valve hole, the rectifying effect on the refrigerant passing through the valve hole 26 can be improved. 【0080】 <Third Embodiment> An example of an expansion valve according to the third embodiment of this disclosure will be described with reference to Figures 11 to 13. Note that the third embodiment will primarily describe the differences from the first embodiment. 【0081】 (composition) Figure 11 shows an exploded perspective view of the valve body 40 and spacer 350 in the expansion valve 310 of the third embodiment. In this embodiment, the spacer 350 is made of metal, for example, stainless steel, and has a thickness of 0.05 mm. The thickness of the spacer 350 is just an example and may be other thicknesses. The spacer 350 is an example of a gap-forming member. 【0082】 As shown in Figure 11, the spacer 350 has a circular portion 352 that is circular when viewed from above, and an extended portion 354 that extends radially from the periphery of the circular portion 352 towards the valve hole 26 when viewed from above. 【0083】 The circular portion 352 and the extended portion 354 are formed to conform to the spherical surface of the valve body 40. Furthermore, when viewed from above, the circular portion 352 has a slightly smaller diameter than, for example, the outer surface of the valve stem 60 (see Figure 1). Also, when viewed from above, the edge of the circular portion 352 is positioned inward from the outer surface of the valve stem 60. In other examples, the circular portion 352 and the valve stem 60 may be formed to the same diameter, and when viewed from above, the edge of the circular portion 352 may overlap with the outer surface of the valve stem 60. The circular portion 352 is sandwiched between the valve body 40 and the valve stem 60, as shown in Figures 12(A) and 12(B). The circular portion 352 is an example of a base. 【0084】 As shown in Figure 11, three extensions 354 are provided around the valve hole 26 at similar intervals. The extensions 354 are fan-shaped, with their width increasing as they move away from the circular portion 352. Furthermore, the extensions 354 are spherical, extending downward from the vertical center of the valve body 40. Note that the extensions 354 are not limited to three, and other numbers may be used. 【0085】 In the above configuration, as shown in Figures 12(A) and 12(B), as the valve body 40 moves upward, the valve body 40 contacts the surface 24a of the valve chamber 24 via the spacer 350. In this embodiment, the portion of the surface 24a of the valve chamber 24 that the valve body 40 contacts via the spacer 350 is defined as the valve seat 24b. In this embodiment, the valve seat 24b is included in the surface 24a. That is, the valve body 40 seats on the valve seat 24b via the spacer 350 (see Figure 12(A)). Figure 12(B) shows the state after the valve body 40 has moved from the closed state. In this embodiment, the closed state is defined as the state in which the valve body 40 moves toward the valve hole 26 and seats on the valve seat 24b via the spacer 350. In other words, in this embodiment, the closed state is the state in which the valve body 40 is seated on the valve seat 24b. 【0086】 Specifically, when the valve body 40 is seated on the valve seat 24b, the extended portion 354 of the spacer 350 is sandwiched between the valve body 40 and the valve seat 24b, as shown in Figure 13(B). In other words, the valve body 40 and the valve seat 24b are in a non-contact state. As a result, a gap 356 is formed between adjacent extended portions 354, allowing refrigerant to pass between the valve body 40 and the valve seat 24b, as shown in Figure 13(A). In other words, when the valve body 40, which has moved toward the valve seat 24b, is immobilized, the extended portion 354 of the spacer 350 is sandwiched between the valve body 40 and the valve seat 24b, forming a gap 356 between the valve body 40 and the valve seat 24b. 【0087】 As a result, even when the valve body 40 is seated on the valve seat 24b, a small amount of refrigerant flows through the gap 356, causing a small amount of refrigerant to circulate in the flow path of the refrigerant circulation system. For example, if the refrigerant contains a lubricant, the lubricant will circulate in the flow path even when the valve body 40 is seated on the valve seat 24b. This ensures that lubricant is supplied to each device. 【0088】 (summary) As explained above, in the expansion valve 310, the circular portion 352 of the spacer 350 is sandwiched between the valve body 40 and the valve stem 60. Furthermore, the extended portion 354 is spherical and extends downward from the vertical center of the valve body 40, thereby covering the valve body 40 from the outside with its spherical surface. For this reason, the spacer 350 can be attached to the valve body 40 without the need for a dedicated mounting member. Moreover, because the circular portion 352 of the spacer 350 is sandwiched between the valve body 40 and the valve stem 60, displacement of the spacer 350 relative to the valve body 40 can be suppressed. In other words, the posture of the spacer 350 can be maintained so that the center of the circular portion 352 of the spacer 350 is at its highest position. 【0089】 Although this disclosure has described in detail a particular embodiment, it will be apparent to those skilled in the art that this disclosure is not limited to such embodiments, and that various other embodiments are possible within the scope of this disclosure. For example, in the above embodiment, the gaps 56, 256, and 356 through which the refrigerant flows are part of a groove defined by a pair of adjacent extensions 54, 254, and 354 and the surface 24a of the valve chamber 24. When viewed from above, this groove extends radially around the valve hole 26, but when viewed from above, this groove may extend spirally around the valve hole. However, in this case, the effect achieved by the groove extending radially around the valve hole 26 is not achieved. 【0090】 Furthermore, in the above embodiment, the extensions 54, 254, and 354 of the spacers 50, 250, and 350 were arranged at similar intervals in the circumferential direction of the valve hole 26 when viewed from above, but they may be arranged at different intervals. However, in this case, the effect achieved by arranging them at similar intervals will not be achieved. 【0091】 Furthermore, in the second embodiment described above, the cylindrical portion 252 of the spacer 250 is, for example, cylindrical. The cylindrical portion 252 is not limited to being cylindrical, as long as it is cylindrical and can be fitted into the valve hole 26. However, as in the second embodiment described above, it is preferable that it has the same cross-sectional shape (cylindrical) as the valve hole 26. Furthermore, the cylindrical portion 252 is formed as a continuous cylindrical shape around the circumference, as an example. In other examples, the cylindrical portion 252 may be a cylindrical shape with both ends in the circumferential direction and a gap between these ends. In other words, the protruding portion 252a may not be a continuous cylindrical shape around the circumference, but a cylindrical shape with a gap in a part of the circumferential direction. As an example of this, the cylindrical portion 252 may be a cylindrical shape with a cross-sectional shape perpendicular to its axis being arc-shaped. Thus, when the cylindrical portion 252 is formed as a cylindrical shape, it includes being formed as a continuous cylindrical shape around the circumference, and being formed as a cylindrical shape with both ends in the circumferential direction and a gap between these ends. When the protruding portion 252a has both ends in the circumferential direction, the gap between these ends is preferably less than 180 degrees around the axis of the valve hole 26, and the smaller the gap, the better. 【0092】 Furthermore, in the second embodiment described above, the cylindrical portion 252 of the spacer 250 had a protruding portion 252a that projected upward from the outlet of the valve hole 26, but the entire cylindrical portion may be housed within the valve hole. However, in this case, the effect achieved by having the protruding portion will not be realized. [Explanation of symbols] 【0093】 10 Expansion valve 12 Valve body 20a Entrance 24 valve chambers 24a Surface (an example of the inner surface) 24b Valve seat 26 valve holes 40 valve body 44. Coil spring (an example of a biasing member) 50 Spacer (an example of a gap-forming member) 54 Extension section 54b Tip (Example of mounting part) 56 gaps 60 valve stems 210 Expansion valve 250 Spacer (an example of a gap-forming member) 252 Cylindrical section (an example of a mounting section) 252a Projecting part 254 Extension section 256 gaps 310 Expansion valve 350 Spacer (an example of a gap-forming member) 352 Circle section (an example of the base) 354 Extension section 356 gap

Claims

[Claim 1] A valve body having an inlet, a valve chamber through which fluid flows in via the inlet, and a valve opening through which the fluid flows out of the valve chamber, A valve body is positioned in the valve chamber and adjusts the flow rate of the fluid flowing through the valve hole by moving closer to or further away from the valve hole, The valve body or valve element is integrated with the valve element and, when the valve element approaches the valve hole, is sandwiched between the valve element and the inner surface of the valve chamber, and in this sandwiched state, a gap forming member is formed between the valve element and the inner surface of the valve chamber, forming a gap that constitutes a part of the flow path connecting the inlet side of the valve chamber and the valve hole. The valve hole is cylindrical in shape, with the valve body extending in a direction toward and toward the valve hole. The gap-forming member is arranged at intervals in the circumferential direction of the valve hole and extends radially in the direction of the valve hole when viewed from the approach-to-separation direction, and has a plurality of extended portions including a clamped portion that is sandwiched between the inner surface of the valve chamber and the valve body. Expansion valve. [Claim 2] The gap-forming member has a mounting portion that is fitted into the valve hole. The expansion valve according to claim 1. [Claim 3] A valve body having an inlet, a valve chamber through which fluid flows in via the inlet, and a valve opening through which the fluid flows out of the valve chamber, A valve body is positioned in the valve chamber and adjusts the flow rate of the fluid flowing through the valve hole by moving closer to or further away from the valve hole, The valve body or valve element is integrated with the valve element and, when the valve element approaches the valve hole, is sandwiched between the valve element and the inner surface of the valve chamber, and in this sandwiched state, a gap forming member is formed between the valve element and the inner surface of the valve chamber, forming a gap that constitutes a part of the flow path connecting the inlet side of the valve chamber and the valve hole. The gap-forming member has a mounting portion that is fitted into the valve hole, The mounting portion has a protruding portion that extends downstream from the outlet of the valve hole in the direction of fluid flow, and the protruding portion is formed in the shape of a cylindrical tube that is continuous around the axis of the valve hole, or in the shape of having both ends in the circumferential direction of the axis and the ends being separated from each other. Expansion valve. [Claim 4] A valve body having an inlet, a valve chamber through which fluid flows in via the inlet, and a valve opening through which the fluid flows out of the valve chamber, A valve body is positioned in the valve chamber and adjusts the flow rate of the fluid flowing through the valve hole by moving closer to or further away from the valve hole, A gap-forming member is integrated with the valve body or the valve element and, when the valve element approaches the valve hole, is sandwiched between the valve element and the inner surface of the valve chamber, and in this sandwiched state, forms a gap between the valve element and the inner surface of the valve chamber that constitutes a part of the flow path connecting the inlet side of the valve chamber and the valve hole, A biasing member that biases the valve body toward the inner surface of the valve chamber, The valve comprises a rod-shaped valve stem inserted into the valve hole and positioned on the opposite side of the biasing member between the valve body and the valve body, which moves the valve body against the biasing force of the biasing member, thereby separating the valve body from the valve hole, The gap-forming member has a base that is sandwiched between the valve body and the valve stem. Expansion valve. [Claim 5] The gap-forming member has multiple clamped portions that are sandwiched between the inner surface of the valve chamber and the valve body, with gaps between them in the circumferential direction of the valve hole. The expansion valve according to claim 4. [Claim 6] The valve hole is cylindrical in shape, with the valve body extending in a direction toward and toward the valve hole. The gap-forming member is arranged at intervals in the circumferential direction of the valve hole and has a plurality of extended portions that extend in the radial direction of the valve hole when viewed from the approach-separation direction and include the clamped portion. The expansion valve according to claim 5.

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