Expansion valve

Abstract

To provide an expansion valve capable of preventing the degradation of a vibration insulation function by securing appropriate support of a coil spring.SOLUTION: The expansion valve includes a valve body including a valve chest VC and a valve seat 20, a valve element 3 for approaching / departing the valve seat, an energization device for energizing the valve element to the valve seat, and an operation rod 5 for pressing the valve element in the direction of departing the valve seat against energizing force by the energizing device, the energizing device having a coil spring 41 for generating the energizing force, a valve element support 42 including a circular part 42b and supporting the valve element, and a vibration insulation spring 44 to be displaced together with the valve element support, the vibration insulation spring having an annular base part 44a abutting on the circular part, and a plurality of leg parts 44b extending from the annular base part to the circular part side, the leg parts abutting on the inner wall of the valve chest while being elastically deformed with the edge of the circular part as supporting point.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an expansion valve. [Background technology]

[0002] Conventionally, in refrigeration cycles used in, for example, air conditioners installed in automobiles, a thermostatic expansion valve that adjusts the amount of refrigerant passing through according to temperature has been used. Such a thermostatic expansion valve employs a power element that drives a valve body via an actuating rod using the pressure of a sealed working gas.

[0003] Here, the pressure difference between the pressure upstream and downstream of the valve disc of the expansion valve can cause the valve disc and the actuating rod that presses the valve disc to vibrate, resulting in abnormal noise. In response to this, Patent Document 1 discloses an anti-vibration spring that can be placed inside the valve body of the expansion valve to suppress such vibration. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2018-25332 Summary of the Invention [Problem to be solved by the invention]

[0005] In the expansion valve of Patent Document 1, the valve element is supported by a coil spring via a valve element support and is biased toward the power element by the biasing force of the coil spring. The vibration-proof spring is supported by being sandwiched between the valve element support and the coil spring in the axial direction.

[0006] 18 is a perspective view of the coil spring 41, viewed along the axial direction, through the anti-vibration spring 44' placed on top of the coil spring 41. The anti-vibration spring 44' is formed by press-forming a thin plate material, and has multiple legs 44b' of the same length that extend radially from a central annular base 44a' and then bend, with their tips contacting the inner wall of the valve body (not shown). By contacting the valve body, the legs 44b' are elastically deformed radially inward.

[0007] Here, because the coil spring 41 is made of steel wire wound in a spiral shape, in order to stably support the annular base portion 44a' of the vibration-damping spring 44', it is necessary to cut the upper end in a direction perpendicular to the axial direction to form a flat surface that will serve as a bearing surface for the vibration-damping spring. In Figure 18, the hatched area is the bearing surface 41a that is formed in a crescent shape over about half the circumference of the vibration-damping spring, but because the bearing surface 41a is crescent-shaped, the following problems arise.

[0008] In other words, when the vibration-proof spring 44' is assembled to the valve body, there will be leg portions 44b' that contact the edge of the receiving surface 41a (leg portions 44b' located at the top of the figure) and leg portions 44b' that do not contact the edge of the receiving surface 41a (leg portions 44b' located at the bottom of the figure). The leg portions 44b' that contact the edge of the receiving surface 41a bend around point A, where the leg portions 44b contact the edge of the receiving surface 41a, as a fulcrum, whereas the leg portions 44b that do not contact the edge of the receiving surface 41a bend around point B, for example, where the leg portions 44b contact the outer curved surface of the steel wire of the coil spring 41. If LA is the distance from the center O to point A and LB is the distance from the center O to point B, then LA > LB. In this way, points A and B serve as fulcrums for leg 44b' when it elastically deforms, resulting in a difference in internal stress during elastic deformation between leg 44b' that contacts coil spring 41 at point A and leg 44b' that contacts coil spring 41 at point B. Furthermore, because the surface of the steel wire at point B is inclined according to its spiral shape, there is a risk of twisting when leg 44b' comes into contact. These effects may cause the support of vibration-damping spring 44' to become unstable, which could impair its vibration-damping function.

[0009] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an expansion valve that can ensure proper support for the coil spring and prevent a decrease in vibration-damping function. [Means for solving the problem]

[0010] In order to achieve the above object, the expansion valve according to the present invention comprises: a valve body having a valve chamber and a valve seat; a valve body that moves toward or away from the valve seat; an urging device that urges the valve body toward the valve seat; an actuation rod that presses the valve body in a direction away from the valve seat against the biasing force of the biasing device, the biasing device includes a coil spring that generates the biasing force, a valve element support that has a circular portion and supports the valve element, and a vibration-proof spring that displaces together with the valve element support, the vibration-proof spring has an annular base portion that contacts the circular portion and a plurality of legs that extend from the annular base portion toward the circular portion, The leg portion elastically deforms with the edge of the circular portion as a fulcrum and abuts against the inner wall of the valve chamber. death, the vibration-proof spring is disposed between the valve body and the valve body support, the valve body support and the coil spring are in contact with each other; The valve body is fitted into a central hole formed in the vibration-proof spring and is held by the valve body support. It is characterized by: In order to achieve the above object, an expansion valve according to the present invention comprises a valve body having a valve chamber and a valve seat, a valve element that moves toward or away from the valve seat, a biasing device that biases the valve element toward the valve seat, and an operating rod that presses the valve element in a direction away from the valve seat against the biasing force of the biasing device, wherein the biasing device comprises a coil spring that generates the biasing force, a valve element support that has a circular portion and supports the valve element, and a vibration-proof spring that displaces together with the valve element support, The vibration-damping spring has an annular base that abuts against the circular portion and a plurality of legs that extend from the annular base toward the circular portion, the legs abutting against the inner wall of the valve chamber while elastically deforming with the edge of the circular portion as a fulcrum, the vibration-damping spring is disposed between the valve disc and the valve disc support, and the valve disc support abuts against the coil spring, and the vibration-damping spring has a central hole and a plurality of claws that extend from the inner circumference of the central hole toward the valve disc, and the valve disc is held by the claws. In order to achieve the above object, an expansion valve according to the present invention comprises a valve body having a valve chamber and a valve seat, a valve element that moves toward or away from the valve seat, a biasing device that biases the valve element toward the valve seat, and an operating rod that presses the valve element in a direction away from the valve seat against the biasing force of the biasing device, wherein the biasing device comprises a coil spring that generates the biasing force, a valve element support that has a circular portion and supports the valve element, and a vibration-proof spring that displaces together with the valve element support, and the vibration-proof spring comprises The valve has an annular base that abuts against the circular portion and a plurality of legs that extend from the annular base toward the circular portion, the legs abutting against the inner wall of the valve chamber while elastically deforming with the edge of the circular portion as a fulcrum, the vibration-damping spring is disposed between the valve body and the valve body support, the valve body support abuts against the coil spring, the valve body support has a recess, and the vibration-damping spring has a central hole and a plurality of claws that extend from the inner periphery of the central hole toward the recess, and the valve body is held by the claws. In order to achieve the above object, an expansion valve according to the present invention comprises a valve body having a valve chamber and a valve seat, a valve element that moves toward or away from the valve seat, a biasing device that biases the valve element toward the valve seat, and an operating rod that presses the valve element in a direction away from the valve seat against the biasing force of the biasing device, wherein the biasing device comprises a coil spring that generates the biasing force, a valve element support that has a circular portion and supports the valve element, and a vibration-proof spring that displaces together with the valve element support, The vibration-damping spring has an annular base that abuts against the circular portion and a plurality of legs that extend from the annular base toward the circular portion, the legs abutting against the inner wall of the valve chamber while elastically deforming with the edge of the circular portion as a fulcrum, the vibration-damping spring is disposed between the valve body and the valve body support, the valve body support abuts against the coil spring, the valve body support has a recess, the vibration-damping spring has an engaging portion that is recessed to engage with the recess, and the valve body is held by the engaging portion. In order to achieve the above object, an expansion valve according to the present invention comprises a valve body having a valve chamber and a valve seat, a valve element that moves toward or away from the valve seat, a biasing device that biases the valve element toward the valve seat, and an operating rod that presses the valve element in a direction away from the valve seat against the biasing force of the biasing device, and the biasing device comprises a coil spring that generates the biasing force, a valve element support that has a circular portion and supports the valve element, and a vibration-damping spring that displaces together with the valve element support, The spring has an annular base that abuts against the circular portion and a plurality of legs that extend from the annular base toward the circular portion, the legs abutting against the inner wall of the valve chamber while elastically deforming with the edge of the circular portion as a fulcrum, the vibration-damping spring is disposed between the valve disc and the valve disc support, the valve disc support and the coil spring abut against each other, and notches are formed at the bases of the adjacent legs, and the edge of the notch that is closest to the center of the vibration-damping spring is located radially inward from the outer edge of the circular portion. In order to achieve the above object, an expansion valve according to the present invention comprises a valve body having a valve chamber and a valve seat, a valve element that moves toward or away from the valve seat, a biasing device that biases the valve element toward the valve seat, and an operating rod that presses the valve element in a direction away from the valve seat against the biasing force of the biasing device, and the biasing device comprises a coil spring that generates the biasing force, a valve element support that has a circular portion and supports the valve element, and a valve support that displaces together with the valve element support. and an anti-vibration spring, wherein the anti-vibration spring has an annular base that abuts against the circular portion and a plurality of legs that extend from the annular base toward the circular portion, the legs abutting against the inner wall of the valve chamber while elastically deforming with the edge of the circular portion as a fulcrum, the anti-vibration spring is disposed between the valve body support and the coil spring, the valve body abuts against the valve body support, and the legs of the anti-vibration spring have bent portions at their tips that are inclined toward the center of the anti-vibration spring. In addition, in order to achieve the above object, an expansion valve according to the present invention comprises a valve body having a valve chamber and a valve seat, a valve disc that moves toward or away from the valve seat, a biasing device that biases the valve disc toward the valve seat, and an operating rod that presses the valve disc in a direction away from the valve seat against the biasing force of the biasing device, wherein the biasing device comprises a coil spring that generates the biasing force, a valve disc support that has a circular portion and supports the valve disc, and a vibration-damping spring that displaces together with the valve disc support, wherein the vibration-damping spring has an annular base that abuts against the circular portion and a plurality of legs extending from the annular base toward the circular portion, the legs abut against the inner wall of the valve chamber while elastically deforming with the edge of the circular portion as a fulcrum, and the outer diameter of the circular portion is smaller than the outer diameter of the coil spring. In order to achieve the above object, an expansion valve according to the present invention comprises a valve body having a valve chamber and a valve seat, a valve element that moves toward or away from the valve seat, a biasing device that biases the valve element toward the valve seat, and an operating rod that presses the valve element in a direction away from the valve seat against the biasing force of the biasing device, wherein the biasing device comprises a coil spring that generates the biasing force, a valve element support that has a circular portion and supports the valve element, and a vibration-damping spring that displaces together with the valve element support, the vibration spring has an annular base that contacts the circular portion and a plurality of legs that extend from the annular base toward the circular portion, the legs contacting the inner wall of the valve chamber while elastically deforming with the edge of the circular portion as a fulcrum, the vibration-proof spring is disposed between the valve element support and the coil spring, the valve element and the valve element support contact each other, and notches are formed at the bases of the adjacent legs, and the edge of the notch that is closest to the center of the vibration-proof spring is located radially inward from the outer edge of the circular portion. . [Effects of the Invention]

[0011] The present invention can provide an expansion valve that can ensure appropriate support for the coil spring and prevent a decrease in vibration-damping function. [Brief explanation of the drawings]

[0012] [Figure 1]FIG. 1 is a schematic cross-sectional view showing an example in which the expansion valve according to the first embodiment is applied to a refrigerant circulation system. [Figure 2] FIG. 2 is an enlarged view showing the vicinity of the vibration-proof spring of the expansion valve of this embodiment. [Figure 3] FIG. 3 is a perspective view showing the valve body, valve body support, vibration-proof spring, and coil spring disassembled from the valve main body. [Figure 4] FIG. 4 is a schematic cross-sectional view showing an expansion valve according to the second embodiment. [Figure 5] FIG. 5 is a perspective view showing the valve element, valve element support, vibration-proof spring, and coil spring disassembled from the valve body. [Figure 6] FIG. 6 is a schematic cross-sectional view showing an expansion valve according to the third embodiment. [Figure 7] FIG. 7 is an enlarged view showing the vicinity of the vibration-proof spring of the expansion valve of this embodiment. [Figure 8] FIG. 8(a) is a perspective view of the vibration-proof spring of this embodiment, and FIG. 8(b) is a cross-sectional view of the vibration-proof spring. [Figure 9] FIG. 9 is a schematic cross-sectional view showing an expansion valve according to the fourth embodiment. [Figure 10] FIG. 10 is an enlarged view showing the vicinity of the vibration-proof spring of the expansion valve of this embodiment. [Figure 11] FIG. 11(a) is a perspective view of the vibration-proof spring of this embodiment, and FIG. 11(b) is a cross-sectional view of the vibration-proof spring. [Figure 12] FIG. 12(a) is a perspective view of a vibration-proof spring according to a modified example, and FIG. 12(b) is a cross-sectional view of the vibration-proof spring according to the modified example. [Figure 13] FIG. 13 is a schematic cross-sectional view showing an expansion valve according to the fifth embodiment. [Figure 14] FIG. 14 is a perspective view showing the valve body, valve body support, vibration-proof spring, coil spring, and spring receiving member disassembled from the valve main body. [Figure 15] FIG. 15 is a schematic cross-sectional view showing an expansion valve according to the sixth embodiment. [Figure 16]FIG. 16 is a perspective view showing the valve body, valve body support, vibration-proof spring, coil spring, and spring receiving member disassembled from the valve main body. [Figure 17] FIG. 17 is a perspective view of the vibration-proof spring of this embodiment. [Figure 18] FIG. 1 is a diagram showing the relationship between a vibration-proof spring and a coil spring in the prior art. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0014] (Direction definition) In this specification, the direction from the valve disc 3 to the actuating rod 5 is defined as the "upward direction," and the direction from the actuating rod 5 to the valve disc 3 is defined as the "downward direction." Therefore, in this specification, regardless of the position of the expansion valve 1, the direction from the valve disc 3 to the actuating rod 5 is called the "upward direction."

[0015] (First embodiment) The expansion valve 1 of the first embodiment will now be described. Fig. 1 is a schematic cross-sectional view showing an example in which the expansion valve 1 of this embodiment is applied to a refrigerant circulation system 100. Fig. 2 is an enlarged view of the vicinity of the vibration-proof spring of the expansion valve 1, showing the valve in a closed state. Fig. 3 is a perspective view showing the valve disc, valve disc support, vibration-proof spring, and coil spring disassembled from the valve body. The center line of the operating rod 5 of the expansion valve 1 is taken as axis L.

[0016] In this embodiment, the expansion valve 1 is fluidly connected to a compressor 101 , a condenser 102 and an evaporator 103 .

[0017] 1 and 2, an expansion valve 1 includes a valve body 2 having a valve chamber VC, a spherical valve element 3, a biasing device 4, an actuating rod 5, and a power element 8.

[0018] In addition to the valve chest VC, the valve body 2 includes a first flow path 21, a second flow path 22, an intermediate chamber 221, and a return flow path 23. The first flow path 21 is a supply-side flow path, and refrigerant is supplied to the valve chest VC via the supply-side flow path. The second flow path 22 is a discharge-side flow path, and the fluid in the valve chest VC is discharged to the outside of the expansion valve via the flow hole 27, the intermediate chamber 221, and the discharge-side flow path.

[0019] The first flow path 21 and the valve chamber VC communicate with each other through a connecting path (also called an introduction path) 21a having a smaller diameter than the first flow path 21. The valve chamber VC and the intermediate chamber 221 communicate with each other through the valve seat 20 and the flow hole 27.

[0020] The actuating rod insertion hole 28 formed above the intermediate chamber 221 has the function of guiding the actuating rod 5, and the annular recess 29 formed above the actuating rod insertion hole 28 has the function of accommodating the ring spring 6. The ring spring 6 applies a predetermined biasing force by abutting multiple spring pieces against the outer periphery of the actuating rod 5. The configuration of the ring spring 6 is described in, for example, JP 2019-74236 A.

[0021] The valve disc 3 is disposed in the valve chamber VC. As shown in FIG. 2, when the valve disc 3 is seated on the valve seat 20 of the valve body 2, the flow of refrigerant through the flow hole 27 is restricted. This state is called a non-communicating state. However, even when the valve disc 3 is seated on the valve seat 20, a restricted amount of refrigerant may still flow. On the other hand, when the valve disc 3 is separated from the valve seat 20 as shown in FIG. 1, the flow of refrigerant passing through the flow hole 27 increases. This state is called a communicating state.

[0022] The actuating rod 5 is inserted through the flow hole 27 with a predetermined gap. The lower end of the actuating rod 5 is in contact with the upper surface of the valve body 3. The upper end of the actuating rod 5 is fitted into a fitting hole 84c of a stopper member 84, which will be described later.

[0023] The actuating rod 5 can press the valve element 3 in the valve opening direction against the biasing force of the biasing device 4. When the actuating rod 5 moves downward, the valve element 3 moves away from the valve seat 20, and the expansion valve 1 enters the open state.

[0024] The biasing device 4 has a coil spring 41 made of a wire wound in a spiral shape, a valve body support 42, a cylindrical spring receiving member 43 with a bottom, and a vibration-proof spring 44. The wire forming the coil spring 41 has, for example, a circular cross section.

[0025] 3 is formed by cutting the spiral winding in a direction perpendicular to the central axis, and at this time, flat bearing surfaces 41a, 41b are formed by the cut ends on both ends of the coil spring 41. The lower end bearing surface 41b abuts against the bottom surface of the spring bearing member 43, and the upper end bearing surface 41a abuts against the lower surface of the valve body support 42.

[0026] A spring receiving member 43 that supports the lower end of the coil spring 41 can be screwed onto the valve body 2 and has the function of sealing the valve chamber VC and the function of adjusting the biasing force of the coil spring 41.

[0027] In FIG. 2, the valve body support 42 is formed by, for example, forging or cutting a metal material, and comprises a cylindrical portion 42a and a disk portion (also called a circular portion) 42b having a larger diameter than the cylindrical portion 42a, which are connected together.

[0028] A conical recess (also simply referred to as a recess) 42c is formed in the center of the upper surface of the disk portion 42b. Here, an example in which the recess is conical is shown, but it is sufficient that the recess has a shape whose inner peripheral surface slopes downward and whose function is to align the center of the valve element 3 with the central axis of the valve element support 42 when the valve element 3 abuts against it. Therefore, the recess is not limited to a cone; the cone shape of the recess is merely an example, and it may be a pyramid or a sphere as long as it fulfills the above function. The intersection of the outer peripheral surface of the cylindrical portion 42a and the lower surface of the disk portion 42b intersects at an acute angle to cut into the disk portion 42b, forming a recess 42d, but it is also possible to form no recess. The lower surface of the disk portion 42b, excluding the recess 42d, is flat. Since the disk portion 42b is relatively thick and rigid, even when its lower surface is in contact only with the receiving surface 41a of the coil spring 41, it can ensure close contact with the receiving surface 41a, and is therefore stably supported by the coil spring 41.

[0029] Here, when the outer diameter of the disk portion 42b is C and the outer diameter of the coil spring 41 is D, C < D holds.

[0030] As shown in FIGS. 2 and 3, the vibration isolator spring 44 is formed by connecting an annular base portion 44a and a plurality (here, eight) of leg portions 44b. The vibration isolator spring 44 can be integrally formed by press-forming from an elastic metal plate material such as stainless steel or its alloy. It is sufficient that there are three or more leg portions 44b at equal intervals in the circumferential direction.

[0031] The leg portion 44b extends radially from the outer periphery of the annular base portion 44a and then extends downward. Here, eight leg portions 44b of the same length are provided at equal angular intervals. The leg portion 44b includes an upper portion 44d, a side portion 44e, and a protrusion portion 44f. In the leg portion 44b, the boundary portion between the upper portion 44d and the side portion 44e constitutes a bent portion. Except for the bent portion, the upper portion 44d and the side portion 44e extend in a flat plate shape. Therefore, the upper portion 44d excluding the bent portion and the upper and lower surfaces of the annular base portion 44a are respectively connected planes.

[0032] In the free state where elastic deformation does not occur, the intersection angle between the upper portion 44d and the side portion 44e is an obtuse angle.

[0033] The upper portion 44d is connected to the annular base portion 44a. Between the base portions of each leg portion 44b, notch portions 44g having a substantially triangular shape or an arc shape are respectively formed.

[0034] The protrusion portion 44f is formed radially outward near the lower end of the side portion 44e. For example, the protrusion portion 44f can be formed by a spherical surface such as a hemispherical shape or a part of other curved surfaces. When the protrusion portion 44f is mounted in the valve body 2, it elastically contacts the upper wall of the connection passage 21a (the inner wall of the valve chamber VC). However, the dimensions of each part of the leg portion 44b are set so that the protrusion portion 44f does not enter the connection passage 21a even when the valve body 3 is at the lowest limit position.

[0035] The vertical length of the leg 44b can be set to any length as long as the lower end of the leg 44b does not enter the connecting passage 21a at the lowest point within the range of vertical movement of the vibration-proof spring 44, which moves together with the valve disc 3. In particular, it is desirable that the lower end of the leg 44b does not reach the connecting passage 21a so as not to obstruct the flow of refrigerant introduced from the connecting passage 21a into the valve chest VC and to prevent a decrease in flow rate, turbulence, etc., as a result.

[0036] When installing the vibration-damping spring 44, the valve disc support 42 is placed on the upper end of the coil spring 41 so that the cylindrical portion 42a is inserted inside the coil spring 41, and then the vibration-damping spring 44 and valve disc 3 are placed from above in that order. In other words, the vibration-damping spring 44 is sandwiched between the valve disc 3 and the valve disc support 42. Because there is almost no gap between the inner periphery of the coil spring 41 and the outer periphery of the cylindrical portion 42a, relative displacement between the valve disc support 42 and the coil spring 41 in the direction perpendicular to the axis is suppressed.

[0037] 2, when the vicinity of the lower end of the valve disc 3 is held in contact with the conical recess 42c of the valve disc support 42, the outer periphery of the valve disc 3 is in contact with (fits) the inner periphery of the central hole 44c along its entire periphery, thereby maintaining coaxiality among the valve disc 3, valve disc support 42, and vibration-damping spring 44. In this embodiment, the valve disc 3, valve disc support 42, and vibration-damping spring 44 are not joined to one another, thereby reducing the number of assembly steps. However, the valve disc 3, valve disc support 42, and vibration-damping spring 44 may also be joined to one another by welding or the like while assembled concentrically, in which case there may be a gap between the inner periphery of the central hole 44c and the outer periphery of the valve disc 3.

[0038] When assembled, the undersides of the annular base portion 44a and part of the upper portion 44d of the vibration-damping spring 44 are in close contact with the underside of the disk portion 42b of the valve disc support 42. At this time, as shown in Figure 3, the innermost end of the notch 44g (the edge closest to the center of the vibration-damping spring 44) is located radially inward from the outer edge of the disk portion 42b. Therefore, all of the legs 44b can elastically deform with the outer edge of the disk portion 42b as a fulcrum.

[0039] The valve body 3, valve body support 42, vibration-damping spring 44, and coil spring 41 assembled in this manner are attached to the spring receiving member 43, and then inserted into the valve chamber VC of the valve body 2, thereby installing the biasing device 4 in the valve body 2.

[0040] With the biasing device 4 installed in the valve body 2, a downward biasing force is applied to the valve disc 3 from the operating rod 5, and an upward biasing force is applied to the valve disc support 42 from the coil spring 41, so that even if the valve disc 3, valve disc support 42, and vibration-damping spring 44 are not joined together, they can maintain their coaxiality without being disassembled. Furthermore, when the protrusions 44f of the legs 44b of the vibration-damping spring 44 abut against the inner wall of the valve chamber VC, the legs 44b elastically deform in the radial direction with the outer edge of the disc portion 42b of the valve disc support 42 as a fulcrum.

[0041] Next, the power element 8 will be described. In Fig. 1, the power element 8 has a plug 81, an upper cover member 82, a diaphragm 83, a receiving member 86, and a stopper member 84. Here, too, the upper cover member 82 side is the upper side, and the receiving member 86 side is the lower side.

[0042] The top cover member 82 is formed, for example, by pressing a metal plate. The top cover member 82 has an annular outer flange portion 82a and a dome-shaped central portion 82b that is connected to the inner periphery of the outer flange portion 82a. An opening 82c is formed in the center of the central portion 82b and can be sealed with a plug 81.

[0043] The receiving member 86, which faces the top cover member 82, is formed, for example, by pressing a metal plate. The receiving member 86 has an outer diameter approximately the same as the outer diameter of the outer flange portion 82a, and is configured by connecting the flange portion 86a and a cylindrical portion 86b. A male thread 86c is formed on the outer periphery of the cylindrical portion 86b.

[0044] A cylindrical recess 2a is formed at the upper end of the valve body 2, and a female thread 2c that can be threaded onto the male thread 86c is formed on the inner periphery of the recess 2a.

[0045] The diaphragm 83 disposed between the upper cover member 82 and the receiving member 86 is made of a thin, flexible metal (for example, SUS) plate material, and has approximately the same outer diameter as the upper cover member 82 and the receiving member 86.

[0046] The stopper member 84 is composed of a solid cylindrical main body and a disk portion extending radially outward from the main body, and has a blind hole-shaped fitting hole 84c formed in the center of the lower surface of the main body.

[0047] Next, we will explain the procedure for assembling the power element 8. While placing the stopper member 84 between the diaphragm 83 and the receiving member 86, the upper cover member 82, the diaphragm 83, and the receiving member 86 are stacked in this order and pressed in the axial direction, and the outer periphery is welded by, for example, TIG welding, laser welding, plasma welding, or the like, all around to weld them together.

[0048] Next, a working gas is injected into the space surrounded by the upper cover member 82 and the diaphragm 83 (referred to as the pressure actuated chamber PO) through the opening 82c formed in the upper cover member 82, and then the opening 82c is sealed with a plug 81, and the plug 81 is further fixed to the upper cover member 82 using, for example, projection welding.

[0049] At this time, the central portion of the diaphragm 83 is subjected to pressure by the working gas sealed in the pressure actuated chamber PO, causing it to protrude toward the receiving member 86, and the central portion of the diaphragm 83 is supported by abutting against the upper surface of the stopper member 84, which is located in the lower space LS surrounded by the diaphragm 83 and the receiving member 86.

[0050] Thereafter, the male thread 86c formed on the outer periphery of the lower end of the cylindrical portion 86b of the power element 8 is screwed into the female thread 2c formed on the inner periphery of the recess 2a of the valve body 2, and when the male thread 86c is threadedly advanced relative to the female thread 2c, the lower surface of the receiving member 86 comes into contact with the upper end surface of the valve body 2. This allows the power element 8 to be fixed to the valve body 2.

[0051] A packing PK is interposed between the assembled power element 8 and valve body 2, sealing the space within the recess 2a that connects to the lower space LS and preventing refrigerant leakage from the recess 2a. In this state, the lower space LS of the power element 8 communicates with the return flow path 23 via the communication hole 2b formed between the recess 2a and the return flow path 23. Thereafter, the actuating rod 5 is inserted from below the valve body 2, passed through the communication hole 2b, and its upper end is fitted into the fitting hole 84c of the stopper member 84. Furthermore, the valve body 3 and the biasing device 4 are assembled as described above, and the expansion valve 1 is completed.

[0052] (Expansion valve operation) An example of the operation of the expansion valve 1 will be described with reference to Figure 1. The refrigerant pressurized by the compressor 101 is liquefied by the condenser 102 and sent to the expansion valve 1. The refrigerant adiabatically expanded by the expansion valve 1 is sent to the evaporator 103, where it exchanges heat with the air flowing around the evaporator. The refrigerant returning from the evaporator 103 passes through the expansion valve 1 (more specifically, the return flow path 23) and is returned to the compressor 101 side. At this time, by passing through the evaporator 103, the fluid pressure in the second flow path 22 becomes greater than the fluid pressure in the return flow path 23.

[0053] A high-pressure refrigerant is supplied from a condenser 102 to the expansion valve 1. More specifically, the high-pressure refrigerant from the condenser 102 is supplied to the valve chest VC via a first flow path 21.

[0054] As shown in Fig. 2, when the valve disc 3 is seated on the valve seat 20 (in a non-communicating state), the flow rate of the refrigerant delivered from the valve chamber VC to the evaporator 103 through the flow holes 27, the intermediate chamber 221, and the second flow path 22 is restricted. On the other hand, as shown in Fig. 1, when the valve disc 3 is separated from the valve seat 20 (in a communicating state), the flow rate of the refrigerant delivered from the valve chamber VC to the evaporator 103 through the flow holes 27, the intermediate chamber 221, and the second flow path 22 increases. The expansion valve 1 is switched between a closed state and an open state by an actuation rod 5 connected to a power element 8 via a stopper member 84.

[0055] 1, the power element 8 is provided with a pressure actuated chamber PO and a lower space LS separated by a diaphragm 83. Therefore, when the working gas in the pressure actuated chamber PO is liquefied, the diaphragm 83 rises, and the stopper member 84 and the working rod 5 move upward in response to the biasing force of the coil spring 41.

[0056] On the other hand, when the liquefied working gas vaporizes, the diaphragm 83 and the stopper member 84 are pressed downward, causing the actuating rod 5 to move downward. Furthermore, the vaporized refrigerant can pass through the gap between the stopper member 84 and the receiving member 86 to the lower space LS of the power element 8. Therefore, the volume of the working gas in the pressure actuated chamber PO changes depending on the temperature and pressure of the refrigerant flowing through the return flow path 23, driving the actuating rod 5. In other words, in the expansion valve 1 shown in FIG. 1, the amount of refrigerant supplied from the expansion valve 1 to the evaporator 103 is automatically adjusted depending on the temperature and pressure of the refrigerant returning from the evaporator 103 to the expansion valve 1.

[0057] According to this embodiment, the protrusions 44f of the legs 44b of the vibration-proof spring 44 come into contact with the inner wall of the valve chamber VC, causing the legs 44b to elastically deform, and the elastic force of the legs 44b presses the protrusions 44f toward the inner wall of the valve chamber VC with a predetermined force, thereby generating sliding resistance in accordance with the movement of the valve disc 3. This makes it possible to suppress vibration of the valve disc 3 and the actuation rod 5.

[0058] Furthermore, the anti-vibration spring 44 is disposed coaxially with the valve disc support 42, and all of the legs 44b of the anti-vibration spring 44 elastically deform with the outer edge of the disc portion 42b of the valve disc support 42 as a fulcrum, so that the elastic deformation of each leg 44b is uniform. Therefore, the biasing force applied from the anti-vibration spring 44 to the valve disc 3 and the valve disc support 42 is approximately uniform in the circumferential direction, so that in addition to being properly supported, the valve disc 3 and the valve disc support 42 are stably supported, and the anti-vibration function of the anti-vibration spring 44 is also stabilized. In other words, a deterioration in the anti-vibration function of the anti-vibration spring 44 can be prevented.

[0059] Furthermore, because the outer diameter C of the disk portion 42b is smaller than the outer diameter D of the coil spring 41, the leg portions 44b bend with a fulcrum located radially inward from the outer diameter of the coil spring 41. This ensures a long span for the leg portions 44b and reduces the maximum amount of protrusion of the leg portions 44b radially outward, ensuring an appropriate spring constant for the vibration-proof spring 44 while achieving compactness.

[0060] Furthermore, since the vibration-damping spring 44 is in contact with the inner wall of the valve chamber VC above the connecting passage 21a, the leg portion 44b does not interfere with the connecting passage 21a, suppressing the generation of turbulence in the refrigerant introduced from the connecting passage 21a into the valve chamber VC and reducing the noise of the refrigerant passing through.

[0061] In addition, since the vibration-proof spring 44 has the notch 44g on the surface having the annular base 44a, the only bent portion is the leg 44b, which makes it easier to design the vibration-proof spring 44, including setting the spring constant.

[0062] (Second embodiment) Fig. 4 is a schematic cross-sectional view showing an expansion valve 1A in a second embodiment. Fig. 5 is a perspective view showing the valve body, valve body support, vibration-proof spring, and coil spring disassembled from the valve body. In this embodiment, only the configuration of the vibration-proof spring 44A in the biasing device 4A differs from that of the first embodiment; the other configurations are the same as those of the first embodiment, so repeated explanations will be omitted.

[0063] The vibration-proof spring 44A, which can be formed by press-forming a metal plate, differs from the first embodiment in that a plurality of (four in this example) claws 44Ah are formed at equal intervals on the inner periphery of a central hole 44Ac of an annular base 44Aa. The leg portion 44b, including the upper portion 44d, side portion 44e, and protrusion 44f, is the same as in the first embodiment, so a repeated description will be omitted.

[0064] The central hole 44Ac has a larger diameter than the central hole 44c of the first embodiment. The claws 44Ah are, for example, rectangular plate-shaped. The claws 44Ah are bent upward and inclined so as to move away from the central axis as they extend upward (widening outward as they extend upward). As shown in FIG. 5, the claws 44Ah abut against the outer peripheral surface of the lower part (below the center) of the spherical valve body 3, and the radially inward surfaces of the claws 44Ah support the outer peripheral surface of the valve body 3.

[0065] Because the claw portions 44Ah are configured in this manner, when the expansion valve 1 is assembled, the vibration-proof spring 44A is sandwiched between the valve element 3 and the disc portion 42b of the valve element support 42. A downward biasing force is applied to the valve element 3 from the actuation rod 5, and an upward biasing force is applied to the valve element support 42 from the coil spring 41, so that the valve element 3 is pressed toward the valve element support 42. The claw portions 44Ah of the vibration-proof spring 44A are deformed by being pressed by the valve element 3, allowing the valve element 3 to seat in the conical recess 42c. In this way, the elastic deformation of the claw portions 44Ah allows the valve element 3 to be held within the multiple claw portions 44Ah, and the valve element 3 is maintained seated in the conical recess 42c. In other words, the valve element 3 does not separate from the conical recess 42c.

[0066] The valve disc 3 abuts against the conical recess 42c of the disc portion 42b of the valve disc support 42, so that the center of the valve disc 3 is aligned with the center of the valve disc support 42. In this state, the claw portion 44Ah abuts against the lower part of the valve disc 3. At this time, as described above, the claw portion 44Ah has a shape that opens as it moves upward. Therefore, when the claw portion 44Ah receives a downward pressing force from the valve disc 3, the pressing force is broken down into a force (1) perpendicular to the axis of the valve disc support 42 and a force (2) along the axis of the valve disc support 42.

[0067] The force (1) has an aligning effect that acts equally on each vibration-damping spring 44A relative to the valve disc 3 (for example, when a relatively strong force (1) acts on one claw portion 44Ah, the vibration-damping spring 44A is displaced relative to the valve disc 3 in the direction of that force (1), and the force (1) in that direction decreases and becomes equal to the other forces (1)), so it acts as a force that tries to align the center of the vibration-damping spring 44A with the centers of the valve disc 3 and valve disc support 42. As a result, even when the expansion valve 1 is in operation, the vibration-damping spring 44A is subjected to a force that tries to align its center with the centers of the valve disc 3 and valve disc support 42, preventing the vibration-damping spring 44A from becoming misaligned.

[0068] The force (2) acts to press the vibration-proof spring 44A against the valve disc support 42. As a result, the annular base portion 44Aa of the vibration-proof spring 44A is maintained in surface contact with the disc portion 42b of the valve disc support 42. In other words, the vibration-proof spring 44A is prevented from shifting in the up and down direction relative to the valve disc support 42.

[0069] (Third embodiment) Fig. 6 is a schematic cross-sectional view showing an expansion valve 1B in a third embodiment. Fig. 7 is an enlarged view of the vicinity of the vibration-proof spring of the expansion valve 1B, showing the valve in an open state. Fig. 8(a) is a perspective view of the vibration-proof spring 44B, and Fig. 8(b) is a cross-sectional view of the vibration-proof spring 44B. In this embodiment, only the configuration of the vibration-proof spring 44B in the biasing device 4B is different from that of the first embodiment; the other configurations are the same as those of the first embodiment, so repeated explanations will be omitted.

[0070] The vibration-proof spring 44B, which can be formed by press-forming a metal plate, differs from the first embodiment in that a plurality of (four in this example) claws 44Bh are formed at equal intervals on the inner periphery of a central hole 44Bc of an annular base 44Ba. The leg 44b, including the upper portion 44d, side portion 44e, and protrusion 44f, is the same as in the first embodiment, and therefore a repeated description will be omitted.

[0071] The trapezoidal plate-shaped claws 44Bh are bent downward and inclined at a constant angle so as to approach the central axis as they extend downward. The tips of the claws 44Bh are spaced apart from each other. The claws 44Bh support the outer circumferential surface of the valve body 3.

[0072] 6 and 7, when the biasing device 4B is assembled to the valve body 2, a downward biasing force is applied to the valve disc 3 from the operating rod 5, and an upward biasing force is applied to the valve disc support 42 from the coil spring 41, so that the valve disc 3 is pressed toward the valve disc support 42. At this time, the valve disc 3 presses the claws 44Bh, causing them to abut against the conical recess 42c. This ensures that the valve disc 3 is stably supported by the valve disc support 42. Even when the expansion valve 1 is in operation, the multiple claws 44Bh engage with the conical recess 42c, ensuring coaxiality between the vibration-damping spring 44B and the valve disc support 42. Therefore, even if the valve disc 3, the valve disc support 42, and the vibration-damping spring 44B are not joined to one another, they can maintain their coaxiality without coming apart.

[0073] (Fourth embodiment) Fig. 9 is a schematic cross-sectional view showing an expansion valve 1C in a fourth embodiment. Fig. 10 is an enlarged view of the vicinity of the vibration-proof spring of the expansion valve 1C, showing the valve in an open state. Fig. 11(a) is a perspective view of the vibration-proof spring 44C, and Fig. 11(b) is a cross-sectional view of the vibration-proof spring 44C. In this embodiment, only the configuration of the vibration-proof spring 44C in the biasing device 4C is different from that of the first embodiment; the other configurations are the same as those of the first embodiment, so repeated explanations will be omitted.

[0074] The vibration-proof spring 44C, which can be formed by press-forming a metal plate, differs from the first embodiment only in the configuration of the circular base 44Ca, which corresponds to the annular base described above. The upper portion 44d, the side portion 44e, and the leg portion 44b including the protrusion 44f are the same as those in the first embodiment, so a duplicated description will be omitted.

[0075] The circular base 44Ca has a conical portion (also called a recessed engagement portion) 44Ch that protrudes downward corresponding to the conical recess 42c of the valve body support 42. The outer peripheral surface of the valve body 3 is supported by the inner peripheral surface of the conical portion 44Ch.

[0076] 9 and 10, with the biasing device 4C installed in the valve body 2, a downward biasing force is applied to the valve disc 3 from the actuation rod 5, and an upward biasing force is applied to the valve disc support 42 from the coil spring 41, so that the valve disc 3 is pressed toward the valve disc support 42. At this time, the valve disc 3 presses the conical portion 44Ch, causing it to come into close contact with the conical recess 42c. This ensures that the valve disc 3 is stably supported by the valve disc support 42. The conical portion 44Ch engages with the conical recess 42c, ensuring coaxiality between the vibration-proof spring 44C and the valve disc support 42. Therefore, even if the valve disc 3, valve disc support 42, and vibration-proof spring 44C are not joined together, they can maintain their coaxiality without coming apart.

[0077] (Variation) FIG. 12(a) is a perspective view of a vibration-proof spring 44D according to a modified example, and FIG. 12(b) is a cross-sectional view of the vibration-proof spring 44D according to the modified example.

[0078] The anti-vibration spring 44D has a circular opening 44Di formed in the center of a conical portion (also called an engagement portion) 44Dh formed on a circular base 44Da. Other configurations are the same as those of the fourth embodiment, so a repeated explanation will be omitted. When forming the anti-vibration spring 44D by press molding, the conical portion 44Dh is pressed and plastically deformed using a forming die. If the opening 44Di were not present, the plate thickness at the center would become thin, which could result in cracks. Forming the opening 44Di in the center of the conical portion 44Dh can eliminate this problem.

[0079] (Fifth embodiment) Fig. 13 is a schematic cross-sectional view showing an expansion valve 1E in a fifth embodiment. Fig. 14 is a perspective view showing the valve body, valve body support, vibration-proof spring, coil spring, and spring receiving member disassembled from the valve body. In this embodiment, only the configurations of the valve body support 42E and the vibration-proof spring 44E in the biasing device 4E are different from those of the first embodiment; the other configurations are the same as those of the first embodiment, so repeated explanations will be omitted.

[0080] The valve element support 42E is formed by, for example, forging or cutting a metal material, and comprises a cylindrical portion 42Ea and a disk portion (also called a circular portion) 42Eb having a larger diameter than the cylindrical portion 42Ea, which are connected together. A conical recess 42Ec is formed in the center of the upper end of the disk portion 42Eb.

[0081] The vibration-proof spring 44E, which can be formed by press-forming a metal plate, comprises an annular base 44Ea and multiple (eight in this example) legs 44Eb connected together. A central hole 44Ec is formed in the center of the annular base 44Ea. The legs 44Eb extend radially from the outer periphery of the annular base 44Ea and then extend upward.

[0082] The leg portion 44Eb includes a lower portion 44Ed, a side portion 44Ee, and a protrusion 44Ef. The boundary between the lower portion 44Ed and the side portion 44Ee of the leg portion 44Eb forms a bent portion. The lower portion 44Ed and the side portion 44Ee extend in a flat plate shape excluding the bent portion. Therefore, the lower portion 44Ed excluding the bent portion and the upper and lower surfaces of the annular base portion 44Ea are each connected to a flat surface. The base portion of each leg portion 44Eb includes the outer edge of the annular base portion 44Ea and includes a substantially triangular or arc-shaped notch 44Eg (see FIG. 17, described later). The vibration-proof spring 44E resembles the vibration-proof spring 44 of the first embodiment turned upside down.

[0083] During assembly, the vibration-damping spring 44E is placed on the coil spring 41, and the cylindrical portion 42Ea of the valve element support 42E is brought close from above and inserted into the inside of the coil spring 41 while passing through the central hole 44Ec of the vibration-damping spring 44E. The valve element 3 is then placed in the conical recess 42Ec of the valve element support 42. In this embodiment, the vibration-damping spring 44E is sandwiched between the valve element support 42E and the coil spring 41.

[0084] The annular base portion 44Ea and the lower portion 44Ed excluding the bent portion of the vibration-damping spring 44E abut against the receiving surface 41a (see FIG. 18) of the coil spring 41. However, by bending each leg portion 44Eb upward, each leg portion 44Eb abuts against the outer edge of the disk portion 42Eb of the valve body support 42E. Therefore, all of the leg portions 44Eb are elastically deformable with the outer edge of the disk portion 42Eb as a fulcrum, thereby achieving stable vibration-damping function.

[0085] (Sixth embodiment) Fig. 15 is a schematic cross-sectional view showing an expansion valve 1F in a sixth embodiment. Fig. 16 is a perspective view showing the valve body, valve body support, vibration-proof spring, coil spring, and spring receiving member disassembled from the valve body. Fig. 17 is a perspective view of a vibration-proof spring 44F. In this embodiment, only the configuration of the vibration-proof spring 44F in the biasing device 4F differs from the first embodiment; the other configurations are the same as those in the fifth embodiment, so repeated explanations will be omitted.

[0086] The vibration-proof spring 44F, which can be formed by press-molding a metal plate, differs from the fifth embodiment only in the configuration of the legs 44Fb. The rest of the structure is the same as the fifth embodiment, so a duplicated description will be omitted.

[0087] As shown in Figure 17, the leg portion 44Fb is similar to the above-described embodiment in that it has a lower portion 44Fd, a side portion 44Fe, and a protrusion portion 44Ff, but has a bent portion 44Fj at its tip that is bent radially inward (inclined toward the center of the vibration-damping spring 44F).

[0088] Because the legs 44Fb protrude outward in a free state without elastic deformation, the tips of the legs 44Fb must be elastically deformed so as to be constricted radially inward before being inserted into the valve body 2. Furthermore, when the vibration-proof spring 44F is displaced toward the assembly position, as the tips of the legs Fb pass through the connecting passage 21a, they may become caught by engaging with the connecting passage 21a, which may hinder assembly.

[0089] According to this embodiment, by providing a bent portion 44Fj at the tip of the leg portion 44Fb, when assembling the vibration-damping spring 44F, the tip of the leg portion 44Fb is prevented from getting caught on the connecting path 21a and hindering displacement, thereby improving assembly ease.

[0090] It should be noted that the present invention is not limited to the above-described embodiments. Any of the components of the above-described embodiments may be modified within the scope of the present invention. Furthermore, any of the components may be added or omitted from the above-described embodiments.

[0091] As a modification of the above-described embodiment, the valve disc and the valve disc support may be fixed by welding, adhesive, etc. In this modification, the vibration-damping spring may be fixed to at least one of the valve disc and the valve disc support by welding or adhesive, or may not be fixed to both the valve disc and the valve disc support.

[0092] This specification includes the disclosure of the following inventions. (First aspect) a valve body having a valve chamber and a valve seat; a valve body that moves toward or away from the valve seat; an urging device that urges the valve body toward the valve seat; an actuation rod that presses the valve body in a direction away from the valve seat against the biasing force of the biasing device, the biasing device includes a coil spring that generates the biasing force, a valve element support that has a circular portion and supports the valve element, and a vibration-proof spring that displaces together with the valve element support, the vibration-proof spring has an annular base portion that contacts the circular portion and a plurality of legs that extend from the annular base portion toward the circular portion, the leg portion elastically deforms with the edge of the circular portion as a fulcrum and abuts against the inner wall of the valve chamber. An expansion valve characterized by:

[0093] (Second form) The vibration-proof spring is disposed between the valve body and the valve body support, and the valve body support and the coil spring are in contact with each other. An expansion valve according to a first embodiment, characterized in that:

[0094] (Third Form) The valve body is fitted into a central hole formed in the vibration-proof spring and is held by the valve body support. An expansion valve according to a second embodiment, characterized in that:

[0095] (Fourth Form) The vibration-proof spring has a central hole and a plurality of claws extending from the inner periphery of the central hole toward the valve body, and the valve body is held by the claws. An expansion valve according to a second embodiment, characterized in that:

[0096] (Fifth form) The valve body support has a recess, The vibration-proof spring has a central hole and a plurality of claws extending from an inner periphery of the central hole toward the recess, and the valve body is held by the claws. An expansion valve according to a second embodiment, characterized in that:

[0097] (Sixth form) The valve body support has a recess, The vibration-proof spring has an engagement portion that is recessed to engage with the recess, and the valve body is held by the engagement portion. An expansion valve according to a second embodiment, characterized in that:

[0098] (7th form) An opening is formed in the center of the engagement portion. An expansion valve according to a sixth aspect, characterized in that:

[0099] (8th form) a notch is formed at the base of the adjacent leg portion, and an edge of the notch closest to the center of the vibration-proof spring is located radially inward from an outer edge of the circular portion; An expansion valve according to a second embodiment, characterized in that:

[0100] (9th form) The vibration-proof spring is disposed between the valve body support and the coil spring, and the valve body and the valve body support abut against each other. An expansion valve according to a first embodiment, characterized in that:

[0101] (10th form) an introduction hole for introducing a refrigerant into the valve chamber is formed in the inner wall of the valve chamber; The leg portion of the vibration-proof spring has a bent portion at a tip thereof facing radially inward. An expansion valve according to a ninth aspect, characterized in that:

[0102] (11th form) The outer diameter of the circular portion is smaller than the outer diameter of the coil spring. The expansion valves of the first to tenth modes are characterized by the above. [Explanation of symbols]

[0103] 1, 1A, 1B, 1C, 1E, 1F: Expansion valve 2: Valve body 3: Valve body 4, 4A, 4B, 4C, 4D, 4E, 4F: Biasing device 5: Operating rod 6: Ring spring 8: Power Element 20: Valve seat 21: First flow path 22: Second flow path 221: Intermediate Room 23: Return flow path 27: Ventilation hole 28: Actuating rod insertion hole 29: Annular recess 41: Coil spring 42, 42E: Valve support 43: Spring support member 44, 44A, 44B, 44C, 44D, 44E, 44F Anti-vibration springs 81: Stopper 82: Top cover member 83: Diaphragm 84: Stopper member 86: Support member 100: Refrigerant circulation system 101: Compressor 102: Capacitor 103: Evaporator VC: Valve chamber

Claims

1. a valve body having a valve chamber and a valve seat; a valve body that moves toward or away from the valve seat; an urging device that urges the valve body toward the valve seat; an actuation rod that presses the valve body in a direction away from the valve seat against the biasing force of the biasing device, the biasing device includes a coil spring that generates the biasing force, a valve element support that has a circular portion and supports the valve element, and a vibration-proof spring that displaces together with the valve element support, the vibration-proof spring has an annular base portion that contacts the circular portion and a plurality of legs that extend from the annular base portion toward the circular portion, the leg portion abuts against the inner wall of the valve chamber while elastically deforming with the edge of the circular portion as a fulcrum, the vibration-proof spring is disposed between the valve body and the valve body support, the valve body support and the coil spring are in contact with each other; The valve body is fitted into a central hole formed in the vibration-proof spring and is held by the valve body support. An expansion valve characterized by:

2. A valve body having a valve chamber and a valve seat; a valve body that moves toward or away from the valve seat; an urging device that urges the valve body toward the valve seat; an actuation rod that presses the valve body in a direction away from the valve seat against the biasing force of the biasing device, the biasing device includes a coil spring that generates the biasing force, a valve element support that has a circular portion and supports the valve element, and a vibration-proof spring that displaces together with the valve element support, the vibration-proof spring has an annular base portion that contacts the circular portion and a plurality of legs that extend from the annular base portion toward the circular portion, the leg portion abuts against the inner wall of the valve chamber while elastically deforming with the edge of the circular portion as a fulcrum, the vibration-proof spring is disposed between the valve body and the valve body support, the valve body support and the coil spring are in contact with each other; The vibration-proof spring has a central hole and a plurality of claws extending from the inner periphery of the central hole toward the valve body, and the valve body is held by the claws. An expansion valve characterized by:

3. A valve body having a valve chamber and a valve seat; a valve body that moves toward or away from the valve seat; an urging device that urges the valve body toward the valve seat; an actuation rod that presses the valve body in a direction away from the valve seat against the biasing force of the biasing device, the biasing device includes a coil spring that generates the biasing force, a valve element support that has a circular portion and supports the valve element, and a vibration-proof spring that displaces together with the valve element support, the vibration-proof spring has an annular base portion that contacts the circular portion and a plurality of legs that extend from the annular base portion toward the circular portion, the leg portion abuts against the inner wall of the valve chamber while elastically deforming with the edge of the circular portion as a fulcrum, the vibration-proof spring is disposed between the valve body and the valve body support, the valve body support and the coil spring are in contact with each other; The valve body support has a recess, The vibration-proof spring has a central hole and a plurality of claws extending from an inner periphery of the central hole toward the recess, and the valve body is held by the claws. An expansion valve characterized by:

4. A valve body having a valve chamber and a valve seat; a valve body that moves toward or away from the valve seat; an urging device that urges the valve body toward the valve seat; an actuation rod that presses the valve body in a direction away from the valve seat against the biasing force of the biasing device, the biasing device includes a coil spring that generates the biasing force, a valve element support that has a circular portion and supports the valve element, and a vibration-proof spring that displaces together with the valve element support, the vibration-proof spring has an annular base portion that contacts the circular portion and a plurality of legs that extend from the annular base portion toward the circular portion, the leg portion abuts against the inner wall of the valve chamber while elastically deforming with the edge of the circular portion as a fulcrum, the vibration-proof spring is disposed between the valve body and the valve body support, the valve body support and the coil spring are in contact with each other; The valve body support has a recess, The vibration-proof spring has an engagement portion that is recessed to engage with the recess, and the valve body is held by the engagement portion. An expansion valve characterized by:

5. An opening is formed in the center of the engagement portion.

5. The expansion valve according to claim 4.

6. A valve body having a valve chamber and a valve seat; a valve body that moves toward or away from the valve seat; an urging device that urges the valve body toward the valve seat; an actuation rod that presses the valve body in a direction away from the valve seat against the biasing force of the biasing device, the biasing device includes a coil spring that generates the biasing force, a valve element support that has a circular portion and supports the valve element, and a vibration-proof spring that displaces together with the valve element support, the vibration-proof spring has an annular base portion that contacts the circular portion and a plurality of legs that extend from the annular base portion toward the circular portion, the leg portion abuts against the inner wall of the valve chamber while elastically deforming with the edge of the circular portion as a fulcrum, the vibration-proof spring is disposed between the valve body and the valve body support, the valve body support and the coil spring are in contact with each other; a notch is formed at the base of the adjacent leg portion, and an edge of the notch closest to the center of the vibration-proof spring is located radially inward from an outer edge of the circular portion; An expansion valve characterized by:

7. A valve body having a valve chamber and a valve seat; a valve body that moves toward or away from the valve seat; an urging device that urges the valve body toward the valve seat; an actuation rod that presses the valve body in a direction away from the valve seat against the biasing force of the biasing device, the biasing device includes a coil spring that generates the biasing force, a valve element support that has a circular portion and supports the valve element, and a vibration-proof spring that displaces together with the valve element support, the vibration-proof spring has an annular base portion that contacts the circular portion and a plurality of legs that extend from the annular base portion toward the circular portion, the leg portion abuts against the inner wall of the valve chamber while elastically deforming with the edge of the circular portion as a fulcrum, the vibration-proof spring is disposed between the valve body support and the coil spring, and the valve body and the valve body support abut against each other; The leg portion of the vibration-proof spring has a bent portion at a tip end that is inclined toward the center of the vibration-proof spring. An expansion valve characterized by:

8. A valve body having a valve chamber and a valve seat; a valve body that moves toward or away from the valve seat; an urging device that urges the valve body toward the valve seat; an actuation rod that presses the valve body in a direction away from the valve seat against the biasing force of the biasing device, the biasing device includes a coil spring that generates the biasing force, a valve element support that has a circular portion and supports the valve element, and a vibration-proof spring that displaces together with the valve element support, the vibration-proof spring has an annular base portion that contacts the circular portion and a plurality of legs that extend from the annular base portion toward the circular portion, the leg portion abuts against the inner wall of the valve chamber while elastically deforming with the edge of the circular portion as a fulcrum, the vibration-proof spring is disposed between the valve body support and the coil spring, and the valve body and the valve body support abut against each other; a notch is formed at the base of the adjacent leg portion, and an edge of the notch closest to the center of the vibration-proof spring is located radially inward from an outer edge of the circular portion; An expansion valve characterized by:

9. The outer diameter of the circular portion is smaller than the outer diameter of the coil spring. The expansion valve according to any one of claims 1 to 8.

10. A valve body having a valve chamber and a valve seat; a valve body that moves toward or away from the valve seat; an urging device that urges the valve body toward the valve seat; an actuation rod that presses the valve body in a direction away from the valve seat against the biasing force of the biasing device, the biasing device includes a coil spring that generates the biasing force, a valve element support that has a circular portion and supports the valve element, and a vibration-proof spring that displaces together with the valve element support, the vibration-proof spring has an annular base portion that contacts the circular portion and a plurality of legs that extend from the annular base portion toward the circular portion, the leg portion abuts against the inner wall of the valve chamber while elastically deforming with the edge of the circular portion as a fulcrum, The outer diameter of the circular portion is smaller than the outer diameter of the coil spring. An expansion valve characterized by:

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