Expansion valve

Abstract

To provide an expansion valve that can suppress vibrations caused by pulsation occurring in a valve chamber.SOLUTION: An expansion valve 1 comprises a valve body 10 having a valve chamber 11 and an orifice 12, a valve element 20 arranged in the valve chamber 11, a coil spring 41 that is provided in the valve chamber 11 on the opposite side of the orifice 12 across the valve element 20 and urges the valve element 20 toward the orifice 12, and a valve element support member 30. The valve body support member 30 comprises a flange portion 22 that supports the valve element 20 in the axial direction of the orifice 12 at the orifice 12 side end of the coil spring 41, and an inserted portion 35 that is provided to be movable integrally with the valve element 20 in a direction perpendicular to the axial direction of the orifice 12 and is inserted into the coil spring. A bottom wall portion 38 of the inserted portion 35 deforms in response to the pressure inside the valve chamber 11.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] Expansion valves have long been used in refrigeration cycles for air conditioning. A known expansion valve is equipped with a vibration-damping spring that suppresses vibration of a valve disc arranged in a valve chamber. A known vibration-damping spring is equipped with multiple legs that are integrally formed with the valve disc. The multiple legs are in pressure contact with the inner peripheral surface of the valve chamber and act as a leaf spring. This type of vibration-damping spring displaces integrally with the valve disc, and during this displacement, the multiple legs slide in contact with the inner peripheral surface of the valve chamber. Vibrations generated in the valve disc are absorbed and suppressed by the multiple legs sliding in contact with the inner peripheral surface of the valve chamber (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6697976 Summary of the Invention [Problem to be solved by the invention]

[0004] One of the causes of valve disc vibration is pulsation that occurs in the valve chamber.

[0005] An object of the present invention is to provide an expansion valve that can suppress vibrations caused by pulsation occurring in a valve chamber. [Means for solving the problem]

[0006] The expansion valve of the present invention comprises a valve body, a valve element, a coil spring, a support portion, and an inserted portion. The valve body has a valve chamber and an orifice. The valve element is disposed in the valve chamber. The coil spring is provided in the valve chamber on the opposite side of the orifice from the valve element, and biases the valve element toward the orifice. The support portion supports the valve element on the coil spring. The inserted portion is provided so as to be movable integrally with the valve element in a direction perpendicular to the axial direction of the orifice, and is inserted into the coil spring. The inserted portion has an enclosed space therein, and a portion of a wall portion facing the space is a deformable portion that deforms in response to the pressure in the valve chamber. [Effects of the Invention]

[0007] According to the present invention, an expansion valve can be provided that can suppress vibrations caused by pulsation occurring in the valve chamber. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a cross-sectional view showing an expansion valve according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a cross-sectional view showing a main part of the expansion valve. [Figure 3] FIG. 4 is a cross-sectional view showing an expansion valve according to a second embodiment of the present invention. [Figure 4] FIG. 6 is a cross-sectional view showing an expansion valve according to a third embodiment of the present invention. [Figure 5] 5 is a cross-sectional view showing a valve body, a valve body support portion, and a vibration damping spring according to a modified example of the expansion valve of the first embodiment. FIG. [Figure 6] FIG. 6 is a cross-sectional view showing a valve body and a valve body support member according to another modified example of the expansion valve of the first embodiment. [Figure 7] FIG. 10 is a cross-sectional view showing an expansion valve according to a modified example of the expansion valve of the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] [First embodiment] An expansion valve 1 according to a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a cross-sectional view showing an expansion valve 1. FIG. 2 is a cross-sectional view showing a main portion of the expansion valve 1. FIG. 2 shows a valve body 20 and its vicinity. As shown in FIGS. 1 and 2, the expansion valve 1 includes a valve body 10, a valve body 20, a valve body support member 30, a biasing device 40, a power element 50, an actuation rod 60, a vibration damping spring 70, and an O-ring 75. The expansion valve 1 is part of a refrigeration cycle used in, for example, a vehicle. The expansion valve 1 forms part of the flow path between the condenser and the evaporator and part of the flow path between the evaporator and the compressor.

[0010] For convenience of explanation, the direction from the valve body 20 to the orifice 12 (described later) is defined as the up direction, and a linear direction perpendicular to the up direction is defined as the width direction. FIG. 1 is a cross-sectional view taken along both the up-down direction and the width direction. FIG. 2 is a cross-sectional view taken along both the up-down direction and the width direction.

[0011] As shown in Figure 1, the valve body 10 has a valve chamber 11, an orifice 12, an inlet passage 13, an outlet passage 14, a return passage 15, and a hole 16. A hole 10a is formed in the lower part of the valve body 10. The hole 10a opens to the lower end of the valve body 10. A female thread 10b is formed in the lower end of the inner circumferential surface of the hole 10a. A part of the hole 10a forms the valve chamber 11.

[0012] The orifice 12 is formed at the upper end of the valve chamber 11. A throat portion that is continuous with the orifice is formed downstream of the orifice 12. The periphery of the orifice 12 is a valve seat on which the valve element 20 is seated. The inflow passage 13 is formed at the bottom of the valve body 10. The inflow passage 13 is a flow path that allows the refrigerant to flow into the valve chamber 11. The inflow passage 13 extends in the width direction.

[0013] The outflow passage 14 is formed in the vertical middle of the valve body 10. The outflow passage 14 is a flow path that allows the refrigerant that has passed through the orifice 12 to flow out of the valve body 10. The outflow passage 14 extends in the width direction. Furthermore, the outflow passage 14 includes a throat portion that is located immediately downstream of the orifice 12 and extends in the vertical direction. The return passage 15 is formed in the upper part of the valve body 10. The return passage 15 is a flow path that allows the refrigerant that has passed through the evaporator to flow. The return passage is part of the flow path that connects the evaporator and the compressor. The return passage extends in the width direction.

[0014] The hole 16 is formed between the return flow path 15 and the outflow path 14, and extends in the vertical direction. The end of the hole 16 on the return flow path 15 side opens to the return flow path 15. The end of the hole 16 on the outflow path 14 side opens to the outflow path 14. An operating rod 60 is arranged in the hole 16 so as to be movable in the axial direction of the operating rod 60.

[0015] The hole 16 has a first hole portion 17 and a second hole portion 18. The first hole portion 17 is a portion of the hole 16 adjacent to the return flow path 15. An O-ring 75 is provided in the first hole portion 17.

[0016] The second hole portion 18 is a portion below the first hole portion 17. The second hole portion 18 has a smaller cross section than the first hole portion 17. The cross-sectional shape and size of the second hole portion 18 are such that the actuating rod 60 can slide against the inner circumferential surface of the second hole portion 18. In this embodiment, since the actuating rod 60 is cylindrical, the cross-sectional shape of the second hole portion 18 is circular. The inner diameter of the second hole portion 18 is slightly larger than the outer diameter of the actuating rod 60. The second hole portion 18 is an example of a guide portion that guides the displacement of the actuating rod 60 by the actuating rod 60 sliding against it.

[0017] 2, the valve element 20 is disposed in the valve chamber 11. The valve element 20 is, for example, spherical.

[0018] The valve body support member 30 includes a first member 31 and a second member 32. The first member 31 constitutes a support portion that supports the valve body 20 on a coil spring 41 of the biasing device 40, which will be described later.

[0019] The first member 31 includes a mounting portion 33 and a flange portion 34. The valve body 20 is mounted on the mounting portion 33. The mounting portion 33 is, for example, columnar and extends in the vertical direction, and is, for example, cylindrical. The upper end surface of the mounting portion 33 is recessed, for example, in a conical shape. The valve body 20 is mounted in this recess. The mounting portion 33 may be fixed to the valve body 20. The fixing means is, for example, welding or an adhesive.

[0020] The flange 34 extends outward from, for example, the lower end of the mounting portion 33. The flange 34 is annular, for example, circular, and functions as a support that supports the valve body 20 in the axial direction of the orifice 12 on the orifice 12-side end of a coil spring 41 (described later).

[0021] In this embodiment, the flange 34 is indirectly supported by the coil spring 41 via a flange 36 of the second member 32 (described later) and the vibration damping spring 70. Here, "support" includes both direct support, i.e., contact, and indirect support, i.e., contact via another member or the like. The lower surface of the first member 31 is, for example, a plane perpendicular to the axial direction of the mounting portion 33.

[0022] The second member 32 is fixed to the lower end surface of the first member 31. The second member 32 constitutes an inserted portion that is inserted into the coil spring 41. The second member 32 has a cylindrical, bottomed inserted portion 35, for example, a bottomed cylindrical inserted portion 35, and a flange portion 36 formed at the upper end opening of the inserted portion 35.

[0023] The second member 32 is disposed coaxially with the first member 31. Here, "coaxial" means that the center line of the first member 31, which in this embodiment is the axis of the placement portion 33, and the center line of the inserted portion 35, which in this embodiment is the axis of the inserted portion 35, coincide with each other. Alternatively, they may be approximately coaxial. "Approximately coaxial" means that deviation due to manufacturing errors, for example, is allowed.

[0024] The inserted portion 35 has a tubular portion 37 and a bottom wall portion 38. The tubular portion 37 is tubular, for example, cylindrical. The bottom wall portion 38 is provided at the bottom opening of the tubular portion 37 and closes the bottom opening.

[0025] The inserted portion 35 is inserted into the coil spring 41 from the upper end of the coil spring 41. The flange portion 36 is placed on the upper end of the coil spring 41 via the vibration damping spring 70. The axial length of the inserted portion 35 is set to a length that allows the inserted portion 35 to abut against the inner periphery of the coil spring 41, thereby preventing the valve element support member 30 from falling off the coil spring 41, even if the valve element support member 30 is tilted with respect to the coil spring 41 during assembly of the expansion valve 1.

[0026] In this embodiment, when inserted portion 35 is disposed inside coil spring 41, it is sized to have a gap around the entire circumference between it and coil spring 41. This gap is, for example, a gap that allows inserted portion 35 to be inserted into coil spring 41 without interfering with the expansion and contraction of coil spring 41. In this embodiment, because inserted portion 35 is cylindrical, the diameter of the outer circumferential surface of inserted portion 35 is set to be slightly smaller than the inner diameter of coil spring 41.

[0027] The bottom wall 38 of the inserted portion 35 is flexible. Flexibility here means that it can deform in response to pressure fluctuations within the valve chamber 11. In this embodiment, the second member 32 is a single member, i.e., the tubular portion 37 and the bottom wall 38 of the inserted portion 35 are integrally formed. As an example, the second member 32 can be formed by press-molding a plate member. As another example, the bottom wall 38 may be formed by fixing a separate member to the tubular portion 37. The bottom wall 38 is an example of a deformable portion.

[0028] The flange portion 36 extends outward from the upper edge of the inserted portion 35. The flange portion 36 is annular, for example, circular. The outer diameter of the flange portion 36 is, for example, the same as the outer diameter of the flange portion 34 of the first member 31. The flange portion 36 is fixed to the underside of the flange portion 34. The flange portion 36 functions as a fixed portion for fixing the inserted portion 35 to the flange portion 34. A fixing means for fixing the flange portion 36 and the flange portion 34 is, for example, welding. In another example, the fixing means may be an adhesive. A fixing portion 39 for fixing the flange portion 36 and the flange portion 34 seals the internal space of the inserted portion 35. The fixing portion 39 is constituted by the above-mentioned fixing means. The fixing portion 39 is annular and extends continuously around the inserted portion 35.

[0029] The biasing device 40 biases the valve body 20 toward the orifice 12. In this embodiment, the biasing device 40 biases the valve body 20 toward the orifice 12 via the valve body support member 30. The biasing device 40 includes a coil spring 41, an adjustment screw 42, and a seal member 45.

[0030] The adjusting screw 42 includes a lid portion 43 and a support portion 44. The lid portion 43 closes the opening at the lower end of the hole 10a of the valve body 10. A male thread 43a is formed on the outer peripheral surface of the lid portion 43. The male thread 43a is threadedly engaged with a female thread 10b formed in the opening 10a of the valve body 10, thereby fixing the lid portion 43 to the opening at the lower end of the hole 10a.

[0031] The support portion 44 is formed on the valve chamber 11 side of the lid portion 43. The support portion 44 is cylindrical and at least the lower end portion of the coil spring 41 is disposed therein. In this embodiment, the lower end portion of the coil spring 41 is disposed therein. Here, the lower end portion includes the lower end and its vicinity. The support portion 44 is coaxial with the orifice 12.

[0032] The coil spring 41 is disposed within the support portion 44. The outer diameter of the coil spring 41 is slightly smaller than the inner diameter of the support portion 44. "Slightly smaller" means that there is a slight gap between the coil spring 41 and the inner peripheral surface of the support portion 44. The slight gap is a gap that allows the coil spring 41 to be inserted into the support portion 44 without hindering the expansion and contraction of the coil spring 41. The upper end of the coil spring 41 abuts against the lower surface of the flange portion 34 of the valve body support member 30 via the vibration damping spring 70.

[0033] The seal member 45 is provided between the outer peripheral surface of the support portion 44 and the inner peripheral surface of the valve chamber 11 .

[0034] The power element 50 is fixed to the upper surface of the valve body 10. The power element 50 generates a driving force that displaces the valve body 20 in the valve opening direction. The power element 50 includes a housing 51 fixed to the valve body 10, a diaphragm 52 provided within the housing 51, and a stopper member 53 that restricts deformation of the diaphragm 52.

[0035] The housing 51 has an opening at its bottom that communicates with the return flow path 15. The diaphragm 52 is provided inside the housing 51. The diaphragm 52 divides the interior of the housing 51 into upper and lower sections. This defines a pressure actuated chamber 54 and a communication chamber 55 inside the housing 51. The pressure actuated chamber 54 is filled with working fluid. The communication chamber 55 is located below the diaphragm 52 and communicates with the return flow path 15.

[0036] The stopper member 53 is disposed within the communication chamber 55. An upper portion of the stopper member 53 abuts against the diaphragm 52. When the diaphragm 52 displaces downward to bulge, the stopper member 53 displaces downward in response to this displacement. The stopper member 53 has a flange portion, and when the flange portion abuts against the housing 51, the stopper member 53 is restricted from moving downward beyond a predetermined position. By restricting the downward movement of the stopper member 53, deformation of the diaphragm 52 is restricted.

[0037] The actuating rod 60 transmits the driving force generated by the power element 50 to the valve body 20. The actuating rod 60 is provided between the stopper member 53 and the valve body 20. The actuating rod 60 is a straight rod extending in the vertical direction. The actuating rod 60 is, for example, cylindrical. The upper end of the actuating rod 60 is supported by the stopper member 53. The actuating rod 60 displaces integrally with the stopper member 53. A portion of the actuating rod 60 is disposed in the return flow path 15, the hole 16, and the outflow path 14. The portion of the actuating rod 60 disposed in the second hole portion 18 of the hole 16 slides against the inner circumferential surface of the second hole portion 18. The lower end of the actuating rod 60 abuts against the valve body 20. The actuating rod 60 is maintained sandwiched between the stopper member 53 and the valve body 20 by the biasing force of the biasing device 40 input via the valve body 20.

[0038] The vibration damping spring 70 suppresses or prevents vibration of the valve body 20. The vibration damping spring 70 includes a base 71 and a plurality of legs 72. The base 71 is provided between the flange portion 36 of the valve body support member 30 and the coil spring 41.

[0039] The base 71 is formed in an annular shape and has a hole. The hole is located at the center of the base 71. A part of the insertion portion 35 of the valve body support member 30 is located in the hole. A plurality of legs 72 are formed continuously with the base 71. The plurality of legs 72 are located at equal intervals around the axis of the hole of the base 71. For example, eight legs 72 are formed.

[0040] The leg portion 72 extends downward from the base portion 71 in a direction perpendicular to the axis of the base portion 71. In other words, the direction perpendicular to the axis of the base portion 71 is an example of a direction intersecting the direction in which the valve body 20 and the coil spring 41 are aligned. The base portion 71 extends, for example, below the opening of the inlet hole 13 in the valve chamber 11. The lower end of the leg portion 72 is in pressure contact with the inner circumferential surface 11a of the valve chamber 11.

[0041] When the vibration damping spring 70 is installed in the valve chamber 11, it contacts the inner peripheral surface 11a of the valve chamber 11, and is deflected so as to be displaced inward in the radial direction of the hole in the base 71 compared to the initial state. The initial state is the state when the vibration damping spring 70 is not installed in the valve chamber 11.

[0042] The restoring force against this deflection causes the multiple legs 72 of the vibration damping spring 70 to press against the inner circumferential surface 11a of the valve chamber 11. The pressing force caused by this pressing force urges the valve disc support member 30 to a position where the base 31 is coaxial with the support portion 44. As a result, the valve disc 20 is positioned via the valve disc support member 30 at a position where it is coaxial with the orifice 12, which is coaxial with the support portion 44.

[0043] The O-ring 75 is provided in the first hole portion 17 of the hole 16. The O-ring 75 abuts against the inner peripheral surface of the first hole portion 17 and the outer peripheral surface of the operating rod 60. The operating rod 60 is in sliding contact with the O-ring 75. The O-ring 75 is an example of a guide portion that guides the displacement of the operating rod 60.

[0044] Next, a portion of the operation of the expansion valve 1 will be described. The temperature and pressure of the refrigerant in the communication chamber 55 of the power element 50 are transmitted to the diaphragm 52 directly or via the stopper member 53. The volume of the working fluid in the pressure actuated chamber 54 changes depending on the temperature and pressure of the refrigerant received through the diaphragm 52. The diaphragm 52 deforms in response to this volume change, and the working rod 60 is displaced in accordance with this deformation. As the working rod 60 is displaced, the outer peripheral surface of the working rod 60 comes into sliding contact with the O-ring 75. The outer peripheral surface of the working rod 60 also comes into sliding contact with the inner periphery of the second hole portion 18 of the hole 16.

[0045] Furthermore, as the actuation rod 60 is displaced, the valve element 20 is displaced between the closed state and the maximum open state. As the valve element 20 is displaced, the valve element support member 30 and the vibration damping spring 70 are displaced integrally with the valve element 20. As the vibration damping spring 70 is displaced, the multiple legs 72 come into sliding contact with the outer peripheral surface of the support portion 44.

[0046] Vibrations occur in the valve disc 20 due to various causes. The expansion valve 1 has a structure that acts to suppress vibrations after the valve disc 20 starts to vibrate. In this embodiment, this structure is, for example, sliding contact of the multiple legs 72 of the vibration damping spring 70 with the inner circumferential surface 11a of the valve chamber 11, sliding contact of the actuating rod 60 with the second hole portion 18 of the hole 16, and sliding contact of the actuating rod 60 with the O-ring 75.

[0047] These vibration suppression structures can suppress the occurrence of vibration of the valve disc 20. Furthermore, these vibration suppression structures suppress the vibration of the valve disc 20 even after it starts to vibrate. For example, the vibration component in the vertical direction of the vibration is absorbed by the sliding contact of the multiple legs 72 of the first vibration suppression spring 70 with the inner circumferential surface 11a of the valve chamber 11. The vibration component in the direction perpendicular to the vertical direction of the vibration is absorbed by the deflection of the vibration suppression spring 70.

[0048] In this expansion valve 1, the valve disc support member 30 is divided into a first member 31 and a second member 32. Furthermore, the second member 32 is cylindrical with a bottom, and the bottom wall portion 38 is flexible. Therefore, the valve disc support member 30 is lighter than a configuration in which the second member 32 is solid. Therefore, the vibration suppression effect after vibration begins due to the vibration suppression structure described above is enhanced. As a result, vibrations occurring in the valve disc 20 can be suppressed without increasing the spring load of the vibration-damping spring 70, i.e., while suppressing wear on the inner circumferential surface of the valve chamber 11. Furthermore, because the bottom wall portion 38 of the second member 32 is flexible, the bottom wall portion 38 can deform and absorb pulsation within the valve chamber 11. As a result, vibrations of the valve disc 20 caused by the pulsation can also be suppressed.

[0049] [Second embodiment] Next, an expansion valve 1A according to a second embodiment of the present invention will be described with reference to FIG. 3. Components having the same functions as those in the first embodiment are given the same reference numerals as those in the first embodiment, and their description will be omitted. In this embodiment, the configuration of the valve body and the configuration of the valve body support member differ from those in the first embodiment. The other configurations are the same as those in the first embodiment. FIG. 3 is a cross-sectional view taken along the vertical and width directions, showing the main parts of the expansion valve 1A. FIG. 3 shows the valve chamber 11 of the expansion valve 1A and its vicinity.

[0050] As shown in Figure 3, the expansion valve 1A includes a valve body 10, a valve body 20A, a valve body support member 30A, a biasing device 40, a power element 50 (omitted in Figure 3), an actuating rod 60, a vibration damping spring 70, and an O-ring 75 (omitted in Figure 3).

[0051] The valve body 20A has a shape that opens downward, and includes, for example, a valve body main body 21 and a flange portion 22. The valve body main body 21 is, for example, a cylindrical shape with a top, and includes a body portion 23 and an upper wall portion 24. The body portion 23 is, for example, cylindrical. Note that the body portion 23 is not limited to a cylindrical shape. In other examples, it may be a cylindrical shape with a polygonal cross section or a cylindrical shape with an elliptical cross section. The upper wall portion 24 has, for example, a shape that bulges upward. The upper wall portion 24 is, for example, hemispherical.

[0052] The flange portion 22 is formed on the lower edge of the body portion 23. The flange portion 22 has a size and shape that allows the valve body 20A to be supported on the upper end of the coil spring 41. In this embodiment, the flange portion 22 is formed in an annular shape, for example, a circular ring shape. Such a valve body 20A can be formed, for example, by press-molding a single plate member. The flange portion 22 is indirectly supported by the coil spring 41 via the valve body support member 30A and the vibration damping spring 70. The flange portion 22 is an example of a support portion that supports the valve body 20A on the coil spring 41.

[0053] The valve body support member 30A has an inserted portion 35 that is inserted into the coil spring 41, and a fixed portion that is fixed to the flange portion 22 of the valve body 20A. The fixed portion is fixed to, for example, the flange portion 22. The valve body support member 30A has a configuration that is, for example, only the second member 32 of the first embodiment.

[0054] The valve body support member 30A has an inserted portion 35 and a flange portion 36 serving as a fixed portion. The flange portion 36 is fixed to the underside of the flange portion 22 of the valve body 20A by fixing means such as welding or adhesive. The inserted portion 35 is arranged coaxially with the body portion 23. Alternatively, it may be approximately coaxial. "Approximately coaxial" means that misalignment due to manufacturing errors is tolerated. The internal space of the inserted portion 35 is in communication with the internal space of the valve body 20A. A fixing portion 39 that fixes the flange portion 36 and the flange portion 22 is formed by, for example, welding or adhesive. The fixing portion 39 is formed in a ring shape that extends continuously around the inserted portion 35. The fixing portion 39 seals the internal space of the inserted portion 35 from the internal space of the valve body 20A.

[0055] This embodiment achieves the same functions and effects as the first embodiment. Furthermore, by communicating the internal space of the valve body 20A with the internal space of the insertion portion 35, the space that contributes to absorbing pulsation within the valve chamber 11 can be increased. This improves the ability to absorb pulsation within the valve chamber 11.

[0056] [Third embodiment] Next, an expansion valve 1B according to a third embodiment of the present invention will be described with reference to FIG. 4. Components having the same functions as those in the second embodiment are given the same reference numerals and will not be described again. In this embodiment, the configuration of the valve body support member differs from that in the second embodiment. FIG. 4 is a cross-sectional view showing a state in which a main part of the expansion valve 1B is cut along the vertical and width directions. FIG. 4 shows the valve chamber 11 of the expansion valve 1B and its vicinity.

[0057] As shown in FIG. 4, the expansion valve 1B includes a valve body 10, a valve body 20A, a valve body support member 30B, a biasing device 40, a power element 50 (not shown), an actuating rod 60, a vibration damping spring 70, and an O-ring 75 (not shown). The valve body support member 30B has an inserted portion 35B and a flange portion 36. The inserted portion 35B has a cylindrical portion 37B and a bottom wall portion 38B. The cylindrical portion 37B is a bellows. The cylindrical portion 37B is expandable and contractable depending on the pressure inside the valve chamber 11. The cylindrical portion 37B is an example of a deformable portion. The inserted portion 35B is coaxial with the body portion 23 of the valve body 20A. Alternatively, it may be approximately coaxial. Approximately coaxial means that misalignment due to manufacturing errors, for example, is permitted.

[0058] The inserted portion 35B is inserted into the coil spring 41 from the upper end of the coil spring 41. The flange portion 36 is formed on the upper edge of the tubular portion 37B. The flange portion 36 is placed on the upper end of the coil spring 41 via the vibration damping spring 70. The axial length of the inserted portion 35B is set to a length that can prevent the valve element support member 30 from falling off the coil spring 41, even if the valve element support member 30 is tilted with respect to the coil spring 41 during assembly of the expansion valve 1, by the inserted portion 35B abutting against the inner periphery of the coil spring 41.

[0059] In the present embodiment, the inserted portion 35B has a size that provides a gap around the entire circumference between the inserted portion 35B and the coil spring 41 when the inserted portion 35B is disposed inside the coil spring 41. This gap is, for example, a gap that allows the inserted portion 35B to be inserted into the coil spring 41 without interfering with the expansion and contraction of the coil spring 41. In the present embodiment, because the inserted portion 35B is cylindrical, the diameter of the outer circumferential surface of the inserted portion 35B is set to be slightly smaller than the inner diameter of the coil spring 41.

[0060] The bottom wall portion 38B is fixed to the lower end opening of the cylindrical portion 37B. The lower end opening of the cylindrical portion 37B is sealed by the bottom wall portion 38B. The bottom wall portion 38B may be flexible and deformable in response to the pressure inside the valve chamber 11.

[0061] According to this embodiment, the same actions and effects as those of the second embodiment can be obtained. Furthermore, to explain the action unique to this embodiment, in this embodiment, the cylindrical portion 37B expands and contracts in response to the pressure in the valve chamber 11, thereby suppressing pulsation in the valve chamber 11. Note that the second member 32 of the expansion valve 1 of the first embodiment may be configured to have the inserted portion 35B of this embodiment instead of the inserted portion 35.

[0062] In the first embodiment, a configuration has been described in which the flange portion 36 of the second member 32 is fixed to the underside of the flange portion 34 of the first member 31. In another example, as in the modified example shown in Fig. 5, a configuration may be adopted in which the base portion 71 of the vibration damping spring 70 is fixed to the underside of the flange portion 34, and the second flange portion 36 is fixed to the underside of the base portion 71. In other words, the second flange portion 36 is indirectly fixed to the flange portion 34 via the base portion 71. Fixing the inserted portion 35 to the flange portion 34 also includes indirect fixing via the base portion 71 in this manner.

[0063] In this configuration, the base 71 is fixed to the flange 34 by fixing means such as welding or adhesive. The fixing portions 39 that fix the base 71 to the flange 34 are formed in a continuous ring shape around the hole in the base 71. In addition, the flange 36 is fixed to the base 71 by fixing means such as welding or adhesive. The fixing portions 39 that fix the flange 36 to the base 71 are formed in a continuous ring shape around the inserted portion 35. The internal space of the inserted portion 35 is sealed by these fixing portions 39.

[0064] Similarly, in the second embodiment, the base 71 of the vibration damping spring 70 may be fixed to the underside of the flange portion 22 of the valve body 20A, and the flange portion 36 of the valve body support member 30A may be fixed to the underside of the base 71. Similarly, in the third embodiment, the base 71 of the vibration damping spring 70 may be fixed to the underside of the flange portion 22 of the valve body 20A, and the flange portion 36 of the valve body support member 30B may be fixed to the underside of the base 71.

[0065] Furthermore, in the first embodiment, a configuration was described in which the valve disc support member 30 and the vibration damping spring 70 were separate members. In another example, as in the modified example shown in Figure 6, the valve disc support member 30 and the vibration damping spring 70 may be configured as an integrated unit. "Integrated" here means that the valve disc support member 30 and the vibration damping spring 70 are configured as a single member. In other words, the valve disc support member 30 has the legs 72 of the vibration damping spring 70. This example will be explained using Figure 6. Figure 6 shows the valve disc 20 and the valve disc support member 30, and shows the valve disc support member 30 cut in cross section along the vertical and width directions.

[0066] As shown in Figure 6, the flange portion 36 of the second member 32 of the valve element support member 30 according to this modified example comprises the leg portion 72 of the vibration damping spring 70 described in the above embodiment. In other words, the flange portion 36 also functions as the base portion 71 of the vibration damping spring 70. Similarly, in the second embodiment, the flange portion 36 of the valve element support member 30A may be configured integrally with the base portion 71 of the vibration damping spring 70. Similarly, in the third embodiment, the flange portion 36 of the valve element support member 30B may be configured integrally with the base portion 71 of the vibration damping spring 70.

[0067] Furthermore, in the second embodiment, it has been explained that the inserted portion 35 of the second member 32 of the valve body support member 30 has a dimension that can prevent the valve body support member 30 from falling off the coil spring 41 during the assembly work of the expansion valve 1. As one example, the inserted portion 35 has a dimension that does not reach the upper end of the support portion 44 of the biasing screw 42 of the biasing device 40 in the vertical direction.

[0068] In another example, as shown in a modified example in FIG. 7 , the inserted portion 35 may have a dimension such that the lower end of the inserted portion 35 is positioned below the upper end of the support portion 44 when the valve element 20 is in the fully open state. The inserted portion 35 has a dimension such that it does not abut against the bottom surface of the internal space of the support portion 44, so that the valve element 20 can be opened to the fully open state. The fully open state is the fully open state required for the performance of the expansion valve 1. For example, the fully open state is a state in which the flange of the stopper member 53 abuts against the housing 51, thereby stopping the downward movement of the stopper member 53. By having such a dimension, the inserted portion 35 is positioned inside the coil spring 41 exposed from the support portion 44 when in the fully open state. The inserted portion 35 prevents the refrigerant from passing radially through the coil spring 41.

[0069] In other words, the refrigerant is prevented from entering the coil spring 41. As a result, the vibration of the coil spring 41 that occurs when the refrigerant passes through the coil spring 41 is suppressed, and therefore, the generation of noise caused by the vibration of the coil spring 41 is suppressed.

[0070] Furthermore, in this modified example, the lower end of the body 37 of the valve element 20 is also located below the upper end of the support portion 44 when the valve element 20 is in the fully open state. Since the body 37, which has a constant diameter, is located below the upper end of the support portion 44, the gap between the body 37 and the coil spring 41 can be reduced, making it even more difficult for the refrigerant to penetrate into the coil spring 41.

[0071] 7, an example has been described in which inserted portion 35 has a dimension such that, in the maximum valve open state, the lower end of inserted portion 35 is positioned vertically lower than the upper end of support portion 44. In another example, inserted portion 35 may have a dimension such that, in the maximum valve open state, the lower end of inserted portion 35 is positioned vertically at the same position as the upper end of support portion 44. Alternatively, inserted portion 35 may have a dimension such that, in the maximum valve open state, the lower end of body portion 37 is positioned vertically at the same position as the upper end of support portion 44.

[0072] In yet another example, the inserted portion 35 may have a dimension such that, when the opening is equal to or greater than the predetermined opening, the lower end of the inserted portion 35 is at the same position as the upper end of the support portion 44 in the vertical direction, or may be lower than the upper end of the support portion 44. Regardless of the dimension, the inserted portion 35 is sized so as not to abut against the bottom surface of the internal space of the support portion 44, so that the valve can be opened to the set maximum open state. The predetermined opening is, in other words, the lift amount of the valve element 20. For example, the predetermined opening is a lift amount that is half the maximum lift amount. Other examples include the maximum open state and the state immediately after the valve element 20 separates from the valve seat. The predetermined opening can be set arbitrarily depending on the quietness required for the expansion valve 1.

[0073] Alternatively, the inserted portion 35 may have a dimension such that, when the valve body 20 is in the closed state, the lower end of the inserted portion 35 is at the same position as the upper end of the support portion 44 in the vertical direction, or may be positioned lower than the upper end of the support portion 44. Even in a configuration having such dimensions, the inserted portion 35 is set to a dimension such that it does not come into contact with the bottom surface of the internal space of the support portion 44, so that the valve can be opened to the set maximum open state.

[0074] In other words, the lower end of the inserted portion 35 may be located at the same position as the upper end of the support portion 44 in the vertical direction, or may be located within the support portion 44, in either the closed valve state or the state where the opening is at or above the predetermined degree. Furthermore, for example, if the bottom wall portion has a shape that bulges downward and tapers toward the lower end, the lower end of the body portion 37 may be located at the same position as the upper end of the support portion 44 in the vertical direction, or may be located within the support portion 44, in either the closed valve state or the state where the opening is at or above the predetermined degree. Regardless of which of the above-mentioned dimensional configurations the inserted portion 35 has, the inserted portion 35 has dimensions that do not abut against the bottom surface of the internal space of the support portion 44, so that the inserted portion 35 can be opened to the set maximum valve open state.

[0075] The configuration of the modified example shown in FIG. 7 and another modified example related to this modified example are the same as those of the first and third embodiments.

[0076] The above describes an embodiment of the present disclosure with reference to the accompanying drawings. However, it is clear that a person with ordinary knowledge in the field of technology to which the present disclosure pertains can conceive of various modifications or applications within the scope of the technical ideas set forth in the claims, and it is understood that these also naturally fall within the technical scope of the present disclosure. [Explanation of symbols]

[0077] 1, 1A, 1B...expansion valve, 10...valve body, 11...valve chamber, 12...orifice, 20...valve disc, 22...flange portion, 30, 30A, 30B...valve disc support member, 31...first member, 32...second member, 34...flange portion (support portion), 35...inserted portion, 37...cylindrical portion, 37B...cylindrical portion (deformation portion), 38...bottom wall portion (deformation portion), 41...coil spring, 44...support portion (second support portion), 72...leg portion.

Claims

1. a valve body having a valve chamber and an orifice; a valve body disposed in the valve chamber; a coil spring provided in the valve chamber on the opposite side of the valve body from the orifice, the coil spring biasing the valve body toward the orifice; a first support portion that supports the valve body on the coil spring; an inserted portion fixed to the first support portion and inserted into the coil spring; Equipped with the inserted portion has a sealed space therein, and a part of a wall portion facing the space is a deformable portion that deforms in response to pressure in the valve chamber. Expansion valve.

2. a support member that is a separate member from the valve body and has the first support portion and the inserted portion; The expansion valve according to claim 1 .

3. the support member includes a first member constituting the first support portion, and a second member fixed to the first member and constituting the inserted portion, The second member includes a cylindrical tube portion and a bottom wall portion formed at one end of the tube portion opposite the orifice to close the one end and functioning as the deformation portion. The expansion valve according to claim 2.

4. the second member includes a plurality of legs that are in pressure contact with the inner circumferential surface of the valve chamber. The expansion valve according to claim 3.

5. The valve body is hollow and communicates with the inserted portion. The expansion valve according to claim 1 .

6. The valve body includes a hollow main body communicating with the inserted portion, and a flange serving as the first support portion, the flange extending outward from the main body and supported by the coil spring. The expansion valve according to claim 5.

7. a second support portion provided on the opposite side of the coil spring from the orifice, the second support portion accommodating at least an end portion of the coil spring opposite the orifice to support the coil spring; an end of the inserted portion on the side of the second support portion is located at the same position as the end of the second support portion on the side of the orifice in the axial direction of the orifice, or is located within the second support portion, in either of two states, namely, a closed valve state and a state in which the opening degree is equal to or greater than a predetermined value; The expansion valve according to claim 1 .

8. a vibration damping spring provided between the valve body and the coil spring; the vibration damping spring has a plurality of legs extending in a direction intersecting a direction in which the valve body and the coil spring are arranged, The expansion valve according to claim 1 , wherein the plurality of legs are in pressure contact with an inner circumferential surface of the valve chamber and slide against the inner circumferential surface as the valve body is displaced.

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