Valve mechanism

Abstract

The drain trap 100 is provided in the valve chamber 22 and includes a valve seat 4 having a valve hole 41, a valve element 5 that moves forward and backward relative to the valve hole 41 to open and close the valve hole 41, a base 61 that is placed on a first wall surface 12b of the valve chamber 22, a first diaphragm 63 that forms an accommodation chamber S1 between the base 61, and a thermal actuator 6 that is accommodated in the accommodation chamber S1 and has an expansion medium 65 that expands and contracts according to temperature to deform the first diaphragm 63, holds the valve element 5, and moves the valve element 5 forward and backward by the deformation of the first diaphragm 63. The thermal actuator 6 further has a plurality of legs 69 that are placed on the first wall surface 12b by contacting the first wall surface 12b in a point contact state.

Description

[Technical field]

[0001] The technology of this disclosure relates to a valve device. [Background technology]

[0002] Conventionally, there has been known a thermally responsive valve device that opens and closes a valve hole in response to the ambient temperature. For example, in the valve device disclosed in Patent Document 1, a valve hole, a valve body that opens and closes the valve hole, and a thermally responsive device that causes the valve body to open and close the valve hole are provided in a valve chamber. The thermally responsive device has a base, a diaphragm that forms a storage chamber between the base, and an expansion medium that is stored in the storage chamber and expands and contracts in response to temperature to deform the diaphragm, and holds the valve body on the side opposite the storage chamber of the diaphragm. The thermally responsive device displaces the valve body by deforming the diaphragm, causing the valve body to open and close the valve hole. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2013-151960 A Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, the thermally responsive device disclosed in the above-mentioned Patent Document 1 is placed on a predetermined mounting surface in the valve chamber so that the valve body and the valve hole face each other. In such a valve device, foreign matter such as dust and liquids tend to accumulate at the contact portion between the thermally responsive device and the mounting surface. The accumulation of such liquids and foreign matter is undesirable because it may cause the growth of bacteria.

[0005] The technology disclosed herein has been made in consideration of the above circumstances, and has an object to provide a valve device that can suppress accumulation of liquid and foreign matter in the valve chamber. [Means for solving the problem]

[0006] The valve device of the present disclosure includes a casing in which a valve chamber is formed, a valve seat provided in the valve chamber and having a valve hole, a valve element that advances and retreats relative to the valve hole to open and close the valve hole, and a thermal actuator. The thermal actuator is placed on a predetermined mounting portion in the valve chamber, and includes a base, a diaphragm that forms a storage chamber between the base and the diaphragm, and an expansion medium that is housed in the storage chamber and expands and contracts in response to temperature to deform the diaphragm, holds the valve element, and advances and retreats the valve element by deformation of the diaphragm. The thermal actuator further has a plurality of legs that are placed on the mounting portion by contacting the mounting portion in a point contact state or line contact state. Effect of the Invention

[0007] According to the above valve device, it is possible to prevent liquid or foreign matter from remaining in the valve chamber. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a cross-sectional view of a drain trap. [Diagram 2] FIG. 2 is a plan view showing the drain trap as viewed from the inlet side. [Diagram 3] FIG. 3 is an enlarged side view of the valve mechanism. [Figure 4] FIG. 4 is a cross-sectional view showing the valve mechanism when the valve is open. [Diagram 5] FIG. 5 is a bottom view showing the thermally responsive device as viewed from the valve body side. [Figure 6] FIG. 6 is a cross-sectional view showing the valve mechanism when the valve is closed. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, exemplary embodiments will be described in detail with reference to the drawings. Fig. 1 is a cross-sectional view of a drain trap 100. Fig. 2 is a plan view showing the drain trap 100 as viewed from the inlet 21 side.

[0010] The drain trap 100 is provided in a steam pipe or the like of a steam system, and prevents the outflow of steam while allowing drain to flow out. The drain trap 100 is an example of a valve device, and drain and steam are examples of fluids. The drain trap 100 includes a casing 1, a valve seat 4, a valve body 5, and a thermally responsive device 6.

[0011] In this example, the valve seat 4, the valve element 5, and the thermally responsive device 6 form a thermally responsive valve mechanism 3. Specifically, a flow path 2 through which condensate flows is formed in the casing 1, and the valve mechanism 3 is provided in the flow path 2. The valve mechanism 3 closes to close the flow path 2 when the ambient temperature is high, and opens to open the flow path 2 when the ambient temperature is low. In this way, the drain trap 100 allows condensate below a predetermined temperature to flow out, while preventing steam above the predetermined temperature from flowing out.

[0012] The casing 1 is formed with an inlet 21, an outlet 23, and a valve chamber 22 that is in communication with each of the inlet 21 and the outlet 23. That is, the flow path 2 in this example is formed by the inlet 21, the valve chamber 22, and the outlet 23. The drain flows from the inlet 21 into the valve chamber 22, and then flows out of the casing 1 from the outlet 23.

[0013] Specifically, the casing 1 has a first member 11 and a second member 12 that are connected to each other. More specifically, a flange 11a of the first member 11 and a flange 12a of the second member 12 are connected with a gasket 13 sandwiched between them. In this example, both flanges 11a, 12a are fixed by a clamp 7. An inlet 21 is formed in the first member 11, and an outlet 23 is formed in the second member 12. A valve chamber 22 is formed between the first member 11 and the second member 12. The inlet 21, the valve chamber 22, and the outlet 23 have the same axis A, that is, are formed coaxially with each other.

[0014] Fig. 3 is an enlarged side view of the valve mechanism 3. Fig. 4 is a cross-sectional view showing the valve mechanism 3 when the valve is open. Fig. 5 is a bottom view showing the thermally responsive device 6 as viewed from the valve body 5 side.

[0015] The valve mechanism 3 is provided in the valve chamber 22. Specifically, the valve seat 4 is provided in the valve chamber 22, and has a valve hole 41. The valve hole 41 connects the valve chamber 22 and the outlet 23. More specifically, the valve seat 4 is provided in a first wall surface 12b that defines a part of the valve chamber 22. The valve hole 41 is formed coaxially with the valve chamber 22 and the outlet 23, and opens to the first wall surface 12b. In other words, the first wall surface 12b is a surface perpendicular to the axis A. An annular seat surface 42 that surrounds the valve hole 41 is formed on the first wall surface 12b.

[0016] The valve disc 5 advances and retreats relative to the valve hole 41 to open and close the valve hole 41. Specifically, the valve disc 5 is disposed in the valve chamber 22 facing the valve hole 41. The valve disc 5 advances and retreats to seat and separate from the valve seat 4 to open and close the valve hole 41. That is, the valve disc 5 advances into the valve hole 41 and seats on the seat surface 42 to close the valve hole 41. The valve disc 5 retreats from the valve hole 41 and separates from the seat surface 42 to open the valve hole 41. A seal surface 51 that seats and separates from the seat surface 42 is formed on the surface of the valve disc 5 facing the valve hole 41.

[0017] The thermally responsive actuator 6 moves the valve element 5 forward and backward relative to the valve hole 41. In other words, the thermally responsive actuator 6 moves the valve element 5 away from and toward the valve seat 4, causing the valve element 5 to open and close the valve hole 41. The thermally responsive actuator 6 is placed on the first wall surface 12b of the valve chamber 22. The first wall surface 12b is an example of a mounting portion.

[0018] The thermally responsive device 6 has a base 61 , a first diaphragm 63 , an expansion medium 65 , and a plurality of legs 69 , and further has a support member 62 , a second diaphragm 64 , and a contact portion 66 .

[0019] The first diaphragm 63 forms an accommodation chamber S1 between itself and the base 61. Specifically, the first diaphragm 63 is formed in a substantially disk shape. The first diaphragm 63 is deformable so that a central portion thereof is displaced in the direction of the axis A. In other words, the first diaphragm 63 is provided coaxially with the valve chamber 22 and the valve hole 41. The first diaphragm 63 is an example of a diaphragm.

[0020] The base 61 is formed in a substantially disk shape. The base 61 has substantially the same outer diameter as the first diaphragm 63. The base 61 faces the first diaphragm 63. The central portion of the base 61 bulges out toward the opposite side to the first diaphragm 63.

[0021] The expansion medium 65 is accommodated in the accommodation chamber S1, and expands and contracts according to temperature to deform the first diaphragm 63. For example, the expansion medium 65 is a liquid having a boiling point lower than that of water. The expansion medium 65 may be water, or a mixture of water and a liquid having a boiling point lower than that of water.

[0022] The storage chamber S1 is a sealed space. In the storage chamber S1, the first diaphragm 63 is deformed by the expansion and contraction of the expansion medium 65. Specifically, when the expansion medium 65 expands, the first diaphragm 63 is deformed so that the center of the first diaphragm 63 moves away from the base 61, that is, the storage chamber S1 expands. On the other hand, when the expansion medium 65 contracts, the first diaphragm 63 is deformed so that the center of the first diaphragm 63 moves closer to the base 61, that is, the storage chamber S1 shrinks.

[0023] An opening 61a for injecting the expansion medium 65 into the storage chamber S1 is formed in the center of the base 61. The opening 61a is sealed by a plug 67. The plug 67 is fixed to the base 61 by, for example, welding.

[0024] The second diaphragm 64 is formed in a substantially disk shape. The second diaphragm 64 has substantially the same outer diameter as the first diaphragm 63. The first diaphragm 63 and the second diaphragm 64 face each other. More specifically, the second diaphragm 64 faces the surface of the first diaphragm 63 opposite the base 61. In other words, the second diaphragm 64 is provided outside the accommodation chamber S1. The second diaphragm 64 is deformable so that its central portion is displaced in the direction of the axis A.

[0025] The support member 62 sandwiches the first diaphragm 63 and the second diaphragm 64 between the support member 62 and the base 61. Specifically, the support member 62 is formed in a substantially disk shape. The support member 62 has substantially the same outer diameter as the base 61. The support member 62 faces the surface of the second diaphragm 64 on the opposite side to the first diaphragm 63. The support member 62 is fixed to the base 61 with the outer periphery of the first diaphragm 63 and the outer periphery of the second diaphragm 64 sandwiched between the support member 62 and the base 61. In this example, the outer peripheries of the base 61, etc. are fixed by welding. The center of the support member 62 bulges out toward the opposite side to the second diaphragm 64.

[0026] The contact portion 66 transmits the deformation of the first diaphragm 63 to the second diaphragm 64. Specifically, the contact portion 66 is disposed in the space S2 between the first diaphragm 63 and the second diaphragm 64. The contact portion 66 is attached to a surface of the second diaphragm 64 that faces the first diaphragm 63. The contact portion 66 transmits the deformation of the first diaphragm 63 to the second diaphragm 64 by coming into contact with the first diaphragm 63 when the expansion medium 65 expands.

[0027] The thermally responsive actuator 6 holds the valve element 5 and advances and retreats the valve element 5 by deformation of the first diaphragm 63. Specifically, the thermally responsive actuator 6 holds the valve element 5 between the support member 62 and the first diaphragm 63, more specifically, between the support member 62 and the second diaphragm 64. The thermally responsive actuator 6 advances and retreats the valve element 5 through an opening 62a formed in the support member 62.

[0028] Specifically, the valve body 5 is provided on the surface of the second diaphragm 64 opposite to the first diaphragm 63. The valve body 5 is welded with the central portion of the second diaphragm 64 sandwiched between the valve body 5 and the contact portion 66. In other words, the valve body 5 is held by the second diaphragm 64. The valve body 5 is displaced integrally with the central portion of the second diaphragm 64 in response to the deformation of the second diaphragm 64.

[0029] The opening 62a is formed in the center of the support member 62. A part of the valve body 5 can protrude from the opening 62a toward the opposite side to the first diaphragm 63. The valve body 5 advances and retreats through the opening 62a relative to the valve hole 41. Furthermore, the support member 62 is formed with a plurality of openings 62c surrounding the opening 62a. The fluid that has flowed into the valve chamber 22 can flow into the space between the support member 62 and the second diaphragm 64 through the openings 62a and 62c.

[0030] The second diaphragm 64 and the valve body 5 are formed with a through hole 52 penetrating the second diaphragm 64 and the valve body 5. Specifically, holes are formed in the second diaphragm 64 and the valve body 5, and these holes are continuously connected to form the through hole 52. The through hole 52 communicates the space S2 with the valve hole 41 when the valve is closed. A hole 66a connected to the through hole 52 is formed in the center of the contact portion 66. Furthermore, the contact portion 66 is formed with a communication passage 66b that communicates the space S2 with the hole 66a when the contact portion 66 is in contact with the first diaphragm 63.

[0031] The thermally responsive device 6 is placed on the first wall surface 12b by contacting the first wall surface 12b with the multiple legs 69 in point contact with the first wall surface 12b. In other words, the thermally responsive device 6 is placed on the first wall surface 12b in point contact with the first wall surface 12b.

[0032] Specifically, a plurality of legs 69 are provided around the opening 62a in the support member 62. In this example, three legs 69 are provided. More specifically, the legs 69 are provided on the edge of the opening 62a. More specifically, the legs 69 are integrally formed with the edge of the opening 62a.

[0033] 5, the multiple legs 69 are multiple bent pieces formed by bending multiple protrusions formed by partially cutting the edge of the opening 62a outward from the support member 62. That is, multiple pairs of notches 62b (three in this example) are formed in the circumferential direction of the edge of the opening 62a, and one protrusion is formed between each pair of notches 62b. Each protrusion is bent outward from the support member 62, i.e., toward the first wall surface 12b, to form the multiple bent pieces. In this way, the multiple legs 69 are formed in the circumferential direction of the edge of the opening 62a.

[0034] The leg 69 has a contact portion 69a that contacts the first wall surface 12b and is formed in a curved shape. In other words, the tip of the bent piece is formed in a curved shape. More specifically, the contact portion 69a is formed in an arc shape. By forming the contact portion 69a in a curved shape in this manner, the leg 69 contacts the first wall surface 12b in a point contact state.

[0035] The length of the leg 69 in the direction of the axis A is set so that the distance between the valve element 5 (specifically, the seal surface 51) and the valve seat 4 (specifically, the seat surface 42) when the valve is open is a predetermined value. This predetermined value is set based on the displacement amount of the valve element 5 when the valve element 5 is displaced toward the valve hole 41 due to the deformation of the first diaphragm 63, and the required outflow amount of drain when the valve is open. When the predetermined value is small, the valve element 5 is more likely to seat on the valve seat 4, but the required outflow amount is lowered. When the predetermined value is large, the required outflow amount is higher, but the valve element 5 is more difficult to seat on the valve seat 4. In this way, the leg 69 also has a positioning function that determines the relative position of the valve element 5 with respect to the valve seat 4 (i.e., the position of the valve element 5 in the direction of the axis A with respect to the valve seat 4).

[0036] Next, the operation of the drain trap 100 will be described. When the valve mechanism 3 is in an open state as shown in Fig. 4, fluid such as drain or steam flows into the valve chamber 22 from the inlet 21. In the valve chamber 22, the thermally responsive device 6 is heated or cooled by the flowing fluid.

[0037] For example, when a low-temperature fluid such as drain or air flows into the valve chamber 22, the volume of the expansion medium 65 (i.e., the degree of expansion) is small, and the first diaphragm 63 is deformed so that the center of the first diaphragm 63 approaches the base 61, as shown in Fig. 4. At this time, the valve body 5 is separated from the valve seat 4, i.e., the seal surface 51 is separated from the seat surface 42, and the valve hole 41 is opened. Therefore, the fluid that has flowed into the valve chamber 22 passes between the seat surface 42 and the seal surface 51 and flows into the valve hole 41, and then flows out from the outlet 23. In this way, the drain trap 100 allows the flowing-in drain or air to flow out.

[0038] FIG. 6 is a cross-sectional view showing the valve mechanism 3 when the valve is closed. On the other hand, when a high-temperature fluid such as steam flows into the valve chamber 22, the temperature of the valve chamber 22 rises, and the expansion medium 65 expands as shown in FIG. 6. The expansion of the expansion medium 65 deforms the first diaphragm 63, and the center of the first diaphragm 63 is displaced toward the second diaphragm 64. The first diaphragm 63 contacts the contact portion 66 and presses the center of the second diaphragm 64 through the contact portion 66. The valve body 5 displaces (i.e., advances) toward the valve hole 41 in a direction substantially parallel to the axis A together with the center of the second diaphragm 64, and the valve body 5 sits on the valve seat 4, i.e., the seal surface 51 and the seat surface 42 come into close contact with each other, and the valve hole 41 is closed. This prevents steam from flowing out from the valve hole 41. In this way, the drain trap 100 prevents the flowing-in steam from flowing out.

[0039] When the temperature of the expansion medium 65 drops due to heat radiation or the like, the expansion medium 65 contracts. The first diaphragm 63 is deformed so that its center is displaced toward the opposite side to the second diaphragm 64. This also releases the pressure of the first diaphragm 63 on the second diaphragm 64 via the contact portion 66. The second diaphragm 64 is deformed so that its center is displaced toward the first diaphragm 63. The valve body 5, together with the center of the second diaphragm 64, is displaced (i.e., retreated) toward the opposite side to the valve seat 4 in a direction substantially parallel to the axis A, and the seal surface 51 is separated from the seat surface 42, and the valve hole 41 is opened. When the temperature of the expansion medium 65 drops in this way, the steam in the valve chamber 22 is condensed and becomes drain. In other words, although a fluid flows out from the outlet 23, the fluid is not steam but drain.

[0040] Next, the fail-open function will be described. The fail-open function in this example is a function that automatically opens the valve hole 41 when at least one of the first diaphragm 63 and the second diaphragm 64 is damaged when the valve is closed. For example, when the first diaphragm 63 is damaged, the expansion medium 65 leaks from the accommodation chamber S1 to the space S2. The expansion medium 65 leaked into the space S2 flows out to the valve hole 41 through the communication passage 66b, the hole 66a, and the through hole 52. The first diaphragm 63 is deformed by the leakage of the expansion medium 65 so that its center is displaced to the opposite side to the second diaphragm 64. The second diaphragm 64 is released from the pressure of the first diaphragm 63 and deforms so that its center is displaced toward the first diaphragm 63. In response to this, the valve body 5 is lifted off the valve seat 4, and the valve hole 41 is opened. As a result, the high-temperature fluid in the valve chamber 22 flows out from the valve hole 41.

[0041] On the other hand, if the second diaphragm 64 is broken, the high-temperature fluid that has flowed into the valve chamber 22 enters the space S2 through the second diaphragm 64. The high-temperature fluid that has entered the space S2 flows out into the valve hole 41 through the communicating passage 66b, the hole 66a, and the through-hole 52.

[0042] In this way, when either the first diaphragm 63 or the second diaphragm 64 is damaged, the valve hole 41 is substantially opened, and the flow path 2 in the drain trap 100 is opened. Due to this fail-open function, even when either the first diaphragm 63 or the second diaphragm 64 is damaged, the fluid passes through the drain trap 100.

[0043] In this manner, in the valve chamber 22 through which fluids such as drainage flow, the thermally responsive device 6 is placed in point contact with the first wall surface 12b via the multiple legs 69. Therefore, the contact area between the thermally responsive device 6 and the first wall surface 12b is reduced compared to when the thermally responsive device is placed in surface contact with a placement portion such as the first wall surface 12b. This prevents drainage or foreign matter from accumulating at the contact points between the thermally responsive device 6, more specifically the legs 69, and the first wall surface 12b.

[0044] As described above, the drain trap 100 includes the casing 1 in which the valve chamber 22 is formed, the valve seat 4 provided in the valve chamber 22 and having the valve hole 41, the valve element 5 that advances and retreats relative to the valve hole 41 to open and close the valve hole 41, and the thermal actuator 6 placed on the first wall surface 12b of the valve chamber 22. The thermal actuator 6 includes the base 61, the first diaphragm 63 that forms a housing chamber S1 between the base 61, and the expansion medium 65 that is housed in the housing chamber S1 and expands and contracts according to temperature to deform the first diaphragm 63, holds the valve element 5, and advances and retreats the valve element 5 by the deformation of the first diaphragm 63. The thermal actuator 6 further includes a plurality of legs 69 that are placed on the first wall surface 12b by contacting the first wall surface 12b in a point contact state.

[0045] According to this configuration, the thermally responsive device 6 is placed on the first wall surface 12b in point contact through the multiple legs 69. Therefore, the contact area between the thermally responsive device 6 and the first wall surface 12b can be reduced compared to when the thermally responsive device is placed on a mounting portion such as the first wall surface 12b in surface contact. This makes it possible to prevent liquid or foreign matter from accumulating at the contact points between the legs 69 and the first wall surface 12b. This makes it possible to prevent liquid or foreign matter from accumulating in the valve chamber 22, thereby making it possible to prevent the growth of bacteria and other problems caused by this.

[0046] The thermal actuator 6 further includes a support member 62 having an opening 62a formed therein and sandwiching an outer peripheral edge of a first diaphragm 63 between the support member 62 and the base 61, and holds the valve body 5 between the support member 62 and the first diaphragm 63 and moves it forward and backward through the opening 62a. A plurality of legs 69 are provided around the opening 62a in the support member 62.

[0047] This configuration allows the multiple legs 69 to be as close as possible to the valve disc 5 and the valve seat 4. This improves the accuracy of the positioning function that determines the relative position of the valve disc 5 with respect to the valve seat 4 by the length of the legs 69. In other words, the longer the distance between the legs 69 and the valve disc 5 and the valve seat 4, the more significant the effect of error becomes, and the worse the positioning function becomes; however, this example suppresses this effect.

[0048] The legs 69 are formed by bending a plurality of protruding pieces formed by partially cutting off the edge of the opening 62a outwardly of the support member 62.

[0049] According to this configuration, since the legs 69 are provided on the edge of the opening 62a, the distance between the legs 69 and the valve body 5 and the valve seat 4 can be shortened. Therefore, the accuracy of the positioning function of the valve body 5 based on the length of the legs 69 can be improved. In addition, since the edge of the opening 62a is partially cut away, there is no need to prepare separate parts as the legs. Therefore, the number of parts is reduced. In addition, since the legs 69 are formed by bending a part of the edge, the relative position of the valve body 5 with respect to the valve seat 4 can be easily adjusted by changing the bending angle, etc.

[0050] The valve seat 4 is provided on a first wall surface 12b that defines a part of the valve chamber 22. The first wall surface 12b serves as a mounting portion on which the thermally responsive device 6 is mounted.

[0051] According to this configuration, the thermally responsive actuator 6 is placed on the same wall surface on which the valve seat 4 is provided, that is, the legs 69 are in contact with the same wall surface, so that the accuracy of the positioning function of the legs 69 is improved.

[0052] Further, the leg 69 has a contact portion 69a that comes into contact with the first wall surface 12b and is formed in a curved shape.

[0053] According to this configuration, the leg 69 can be brought into point contact with the first wall surface 12b with a simple structure.

[0054] (Other embodiments) As described above, the above embodiment has been described as an example of the technology disclosed in this application. However, the technology in this disclosure is not limited to this, and can be applied to embodiments in which modifications, replacements, additions, omissions, etc. are appropriately performed. In addition, it is also possible to combine the components described in the above embodiment to form a new embodiment. In addition, among the components described in the attached drawings and detailed description, not only components essential for solving the problem but also components that are not essential for solving the problem in order to exemplify the technology may be included. Therefore, the fact that these non-essential components are described in the attached drawings and detailed description should not immediately be taken to mean that these non-essential components are essential.

[0055] For example, the legs 69 may be attached to the edge of the opening 62a in the support member 62 or to the surrounding area thereof as separate parts.

[0056] The number of legs 69 may be four or more.

[0057] In the thermally responsive device 6, the second diaphragm 64 and the contact portion 66 may be omitted.

[0058] Furthermore, the support member 62 may be omitted from the thermally responsive device 6. In that case, the legs 69 are provided on the outer periphery of the base 61 or the outer periphery of the first diaphragm 63, for example.

[0059] The legs 69 may be in line contact with the first wall surface 12b, which is the mounting portion. Even in this case, the contact area between the thermally responsive device 6 and the first wall surface 12b can be reduced compared to when the thermally responsive device is mounted on the mounting portion in surface contact, so that retention of liquid or foreign matter in the valve chamber 22 can be suppressed.

[0060] Furthermore, the shape of the contact portion 69a of the leg 69 may be other than a curved shape. For example, the contact portion 69a of the leg 69 may be formed in a pointed shape to make point contact with the first wall surface 12b, or may be formed in a shape having a straight corner to make line contact with the first wall surface 12b.

[0061] Further, the mounting portion on which the thermally responsive device 6 is mounted may be a wall surface of the valve chamber 22 other than the first wall surface 12b. [Industrial Applicability]

[0062] As described above, the technology of the present disclosure is useful for a valve device. [Explanation of symbols]

[0063] 100 Drain trap (valve device) 1 Casing 12b First wall surface (mounting portion) 22 Valve chamber 4 Valve seat 41 Valve hole 5 Valve body 6. Thermal Response Device 61 Base 62 Support material 62a aperture 63 First diaphragm (diaphragm) 65 Expansion medium 69 legs 69a Contact part S1 Containment Cell

Claims

1. a casing in which a valve chamber is formed; a valve seat provided in the valve chamber and having a valve hole; a valve body that moves forward and backward relative to the valve hole to open and close the valve hole; a diaphragm that is placed on a predetermined placement portion of the valve chamber, a base, and a diaphragm that forms a storage chamber between the base and the base; and a thermal actuator that is contained in the storage chamber and has an expansion medium that expands and contracts in response to temperature to deform the diaphragm, holds the valve body, and moves the valve body forward and backward by deformation of the diaphragm, the thermal actuator further has a plurality of legs that are placed on the placement portion by contacting the placement portion in a point contact state or a line contact state, the thermal actuator further includes a support member having an opening formed in a central portion thereof and configured to sandwich an outer peripheral edge of the diaphragm between the support member and the base, the valve body being held between the support member and the diaphragm and moved forward and backward through the opening; The legs are provided on an edge of the opening in the support member. A valve device characterized in that

2. 2. The valve device according to claim 1, The plurality of legs are a plurality of bent pieces formed by partially cutting off the edge of the opening and bending the protruding pieces toward the outside of the support member. A valve device characterized in that

3. The valve device according to claim 1 or 2, the valve seat is provided on a wall surface that defines a portion of the valve chamber, The mounting portion is the wall surface. A valve device characterized in that

4. The valve device according to claim 1 or 2, The legs have contact portions that come into contact with the placement portion and are formed in a curved shape. A valve device characterized in that

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