Valve

Abstract

To provide a technique for quickly opening a valve for releasing pressure inside a case housing a battery when the pressure inside the case becomes high.SOLUTION: A valve is attached to a case that houses a battery to open and close a gas exhaust port for exhausting gas inside the case to the outside of the case. The valve includes a first valve body that opens and closes the gas exhaust port, an elastic body that presses the first valve body toward the gas exhaust port, and a support body that supports the elastic body. The first valve body includes a first pressure-receiving surface that faces the inside of the case through the gas exhaust port, and a second pressure-receiving surface that is located around the first pressure-receiving surface and receives the pressure of gas exhausted from the gas exhaust port to the outside of the case when the first valve body opens.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The technology disclosed in this specification relates to a valve for releasing pressure inside a case that houses a battery. [Background technology]

[0002] For example, a battery mounted on a vehicle or the like is housed in a case. When the pressure inside the case becomes high, it is necessary to reduce the internal pressure. For example, Patent Document 1 discloses a valve for releasing the pressure inside a case housing a battery. The valve of Patent Document 1 opens when the pressure inside the case becomes greater than a predetermined value, and the gas inside the case is released to the outside. The pressure inside the case is reduced by releasing the gas inside the case to the outside. The valve of Patent Document 1 is of a flap type, and when opening, the valve body opens obliquely with respect to the axis of the gas exhaust port. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-194719 A Summary of the Invention [Problem to be solved by the invention]

[0004] When the pressure inside the case that houses the battery becomes higher than a predetermined value, it is necessary to quickly reduce the pressure inside the case to avoid damage to the case. For this reason, it is required that the valve quickly opens when the pressure inside the case becomes higher than a predetermined value. However, in the valve of Patent Document 1, the valve body opens at an angle to the axis of the gas exhaust port, so that the gas exhausted from inside the case cannot be efficiently received by the pressure receiving surface of the valve body. Thus, when the valve body opens at an angle, there is a problem that the valve does not open quickly.

[0005] This specification discloses a technique for quickly opening a valve for releasing pressure inside a case that houses a battery when the pressure inside the case becomes high. [Means for solving the problem]

[0006] In a first aspect of the present technology, a valve is attached to a case that houses a battery to open and close a gas exhaust port for exhausting gas inside the case to the outside of the case. The valve includes a first valve body that opens and closes the gas exhaust port, an elastic body that presses the first valve body toward the gas exhaust port, and a support body that supports the elastic body. The first valve body includes a first pressure-receiving surface that faces the inside of the case through the gas exhaust port, and a second pressure-receiving surface that is located around the first pressure-receiving surface and receives the pressure of gas exhausted from the gas exhaust port to the outside of the case when the first valve body opens.

[0007] According to this configuration, by providing the first valve body with the second pressure receiving surface, when the first valve body opens, not only the first pressure receiving surface but also the second pressure receiving surface receives the pressure inside the case. This increases the area over which the first valve body receives the pressure of the gas discharged from the gas discharge port when the first valve body opens. This allows the first valve body to open quickly when the pressure inside the case increases.

[0008] In a second aspect, in the first aspect described above, a flow path may be provided between the first valve body and the case through which gas passes when the first valve body is opened and is discharged from the gas discharge port to the outside of the case.

[0009] According to this configuration, when the first valve body is opened, gas inside the case is discharged through a flow path between the first valve body and the case, making it difficult for the gas discharged from the case to flow into the opposite side of the first valve body. Therefore, when the pressure in case 2 increases, the pressure on the opposite side of the first valve body is less likely to increase, and the first valve body can be opened quickly.

[0010] In a third aspect, in the first or second aspect, the case may have an opening communicating with the inside and outside of the case. The valve may further include an attachment portion disposed around the opening and attached to the case, and a tubular portion protruding from the attachment portion to the outside of the case. The gas discharge port may be formed at a tip of the tubular portion. The first valve body may include a first portion facing the tubular portion, and a second portion located around the first portion and located closer to the case than the first portion.

[0011] According to this configuration, by providing the cylindrical portion, the gas exhaust port protrudes to the outside of the case, which makes it difficult for water to enter the gas exhaust port from outside the case when the first valve body is opened, thereby making it possible to suppress water from entering the case.

[0012] In a fourth aspect, in the third aspect described above, in a flow path through which gas flows to be discharged from the gas exhaust port to the outside of the case when the first valve body is opened, the area of ​​an upstream flow path formed between the tubular portion and the first valve body may be larger than the area of ​​a downstream flow path formed between the mounting portion and the first valve body during the period from the closed state to when the first valve body opens to a predetermined range.

[0013] According to this configuration, the area of ​​the upstream flow path is larger than the area of ​​the downstream flow path while the first valve body opens to a predetermined range from a closed state. As a result, while the first valve body opens to a predetermined range from a closed state, gas in the case is easily allowed to flow from the gas discharge port through the upstream flow path toward the downstream flow path, while the flow of gas (atmosphere) to the outside of the case via the downstream flow path is suppressed. Therefore, at the initial stage of opening of the first valve body, the pressure in the case acts on the first pressure receiving surface and the second pressure receiving surface, so that the opening stroke of the first valve body is easily increased, gas is easily allowed to flow from the gas discharge port to the outside of the case, and the first valve body can be opened quickly when the pressure in the case increases.

[0014] In a fifth aspect, in the third or fourth aspect described above, in a flow path through which gas flows to be discharged from the gas exhaust port to the outside of the case when the first valve body opens from a closed state beyond a predetermined range, if the area of ​​the opening flow path formed between the upper surface of the tubular portion and the first valve body is D1, the area of ​​the upstream flow path formed between the side surface of the tubular portion and the first valve body is D2, and the area of ​​the downstream flow path formed between the mounting portion and the first valve body is D3, then D1≦D2≦D3 may be satisfied.

[0015] According to this configuration, by configuring the valve so that D1≦D2≦D3 holds when the first valve body opens beyond a predetermined range from a closed state, the area of ​​the flow path through which the gas discharged from the gas discharge port to the outside of the case flows increases from the upstream side to the downstream side. This makes it possible to reduce the resistance applied to the discharged gas when the gas discharged from the gas discharge port and passing through the opening flow path with area D1 passes through the upstream flow path with area D2 and further flows into the downstream flow path with area D3. This makes it possible to suppress a decrease in the flow rate of the gas discharged from the gas discharge port.

[0016] In a sixth aspect, in any one of the first to fifth aspects, the first valve body may further include a protrusion on its outer periphery protruding outward from the case. The protrusion may block the flow of gas discharged from the gas discharge port to the outside of the case, toward the opposite side of the first pressure-receiving surface and the opposite side of the second pressure-receiving surface of the first valve body.

[0017] According to this configuration, the gas discharged from the case through the gas discharge port is blocked by the protrusion and is less likely to move to the opposite side of the pressure receiving surface of the first valve body (i.e., the first pressure receiving surface and the second pressure receiving surface). This makes it possible to prevent the pressure on the opposite side of the pressure receiving surface of the first valve body from increasing due to the gas discharged from the case, and to prevent a decrease in the valve opening speed of the first valve body.

[0018] In a seventh aspect, in any one of the first to sixth aspects, the support may include a cover that covers a surface of the first valve body opposite the first pressure-receiving surface and a surface of the first valve body opposite the second pressure-receiving surface, and the cover may include a first through-hole penetrating the cover.

[0019] According to this configuration, the cover can prevent the gas discharged from the case through the gas discharge port from flowing into the opposite side of the pressure receiving surface of the first valve body (i.e., the opposite side of the first pressure receiving surface and the opposite side of the second pressure receiving surface). On the other hand, if the opposite side of the pressure receiving surface of the first valve body is covered, there is a risk that the first valve body is pushed from the pressure receiving surface side when the first valve body is opened, and the pressure between the first valve body and the cover increases. By providing the cover with the first through hole, when the first valve body is pushed from the pressure receiving surface side, the gas between the first valve body and the cover is discharged from the first through hole. Therefore, even if the cover is provided, it is possible to prevent the pressure on the opposite side of the pressure receiving surface of the first valve body from increasing when the first valve body is opened. Therefore, it is possible to prevent the pressure on the opposite side of the pressure receiving surface of the first valve body from increasing while appropriately supporting the elastic body with the support body.

[0020] In an eighth aspect, in the seventh aspect, the support body may further include a second valve body that opens and closes the first through hole. The second valve body may close when the pressure between the first valve body and the cover is lower than a predetermined value to prevent gas from passing through the first through hole, and open when the pressure between the first valve body and the cover is higher than a predetermined value to allow gas to pass through the first through hole.

[0021] According to this configuration, when the pressure between the first valve body and the cover becomes higher than a predetermined value, the second valve body opens, allowing gas to pass through the first through hole. That is, when the first valve body opens, the pressure between the first valve body and the cover increases, and the second valve body opens. Therefore, when the first valve body opens, the pressure on the side opposite the pressure-receiving surface of the first valve body can be preferably prevented from increasing.

[0022] In a ninth aspect, in the seventh or eighth aspect, the first valve body may further include a protrusion on its outer periphery protruding outward from the case. The protrusion may block the flow of gas discharged from the gas discharge port to the outside of the case, toward the opposite side of the first pressure-receiving surface of the first valve body and the opposite side of the second pressure-receiving surface of the first valve body. The protrusion may be disposed outward from the cover when viewed along the axis of the gas discharge port.

[0023] According to this configuration, the gas discharged from the case through the gas discharge port is blocked by the protrusion and is less likely to move to the side opposite the pressure receiving surface of the first valve body (i.e., the first pressure receiving surface and the second pressure receiving surface), and is also less likely to move to the side opposite the pressure receiving surface of the first valve body due to the cover. Therefore, it is possible to prevent the pressure on the side opposite the pressure receiving surface of the first valve body from increasing due to the gas discharged from the case, and to prevent a decrease in the valve opening speed of the first valve body.

[0024] In a tenth aspect, in any one of the first to ninth aspects, the first valve body may include a second through hole extending from the first pressure-receiving surface to an opposite surface thereof, and a third valve body opening and closing the second through hole. The third valve body may open when the pressure received by the first pressure-receiving surface is lower than a predetermined value to allow gas to pass through the second through hole, and close when the pressure received by the first pressure-receiving surface is higher than the predetermined value to prevent gas from passing through the second through hole.

[0025] According to this configuration, when the pressure received by the first pressure-receiving surface is lower than a predetermined value (i.e., when the first valve body is closed), the third valve body is open. Therefore, when the first valve body is closed, gas can move between the inside and outside of the case via the second communication hole, and it is possible to appropriately respond to environmental changes (e.g., temperature changes, etc.). Furthermore, when the pressure received by the first pressure-receiving surface is higher than a predetermined value (i.e., when the first valve body is open), the third valve body is closed. Therefore, when the first valve body is open, the third valve body closes the second communication hole, so that the first valve body can reliably receive pressure at the first pressure-receiving surface. [Brief description of the drawings]

[0026] [Figure 1] FIG. 1 is a cross-sectional view showing a schematic configuration of a valve according to a first embodiment. [Diagram 2] FIG. [Diagram 3] 5 is a diagram showing the relationship between the pressure acting on a first pressure-receiving surface of the valve body and the valve opening degree of the valve body. FIG. [Figure 4] FIG. 2 is an enlarged view of the main part IV in FIG. [Diagram 5] 1A and 1B are diagrams showing the cover, where (a) is a top view, (b) is a cross-sectional view taken along line BB in (a) showing the valve body in a closed state, and (c) is a cross-sectional view taken along line BB in (a) showing the valve body in an open state. [Figure 6] 6 is a diagram showing the relationship between the flow rate of gas discharged from a gas discharge port when the valve body is opened and the back pressure of the valve body. FIG. [Figure 7] FIG. 7 is an enlarged view of the main part VII of FIG. [Figure 8] 1A and 1B are diagrams for explaining the flow path area of ​​the exhaust flow path of the gas exhausted from the gas exhaust port, in which (a) shows the valve body in a closed state, (b) shows the valve body in a slightly open state, and (c) shows the valve body in a completely open state. [Figure 9] FIG. 11 shows how the valve body opens quickly at the beginning of opening, where (a) shows the relationship between the acting pressure on the first pressure-receiving surface of the valve body and the opening degree of the valve body, (b) shows the relationship between the discharge flow rate of gas discharged from the case and time when the pressure in the case exceeds a predetermined value, (c) shows the relationship between the opening degree of the valve body and time when the pressure in the case exceeds a predetermined value, and (d) shows the relationship between the internal pressure of the case and flow path pressure and time when the pressure in the case exceeds a predetermined value. [Figure 10] Diagram showing the valve when the case is flooded. [Figure 11] FIG. 4 is a cross-sectional view showing another configuration of the valve according to the first embodiment. [Figure 12]10A and 10B are diagrams showing a support provided in a valve of Example 2, in which (a) is a top view, (b) is a cross-sectional view taken along line BB in (a) showing a state in which the valve body is closed, and (c) is a cross-sectional view taken along line BB in (a) showing a state in which the valve body is open. [Figure 13] FIG. 11 is a cross-sectional view showing a schematic configuration of a valve according to a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] Example 1 The valve 10 of this embodiment will be described with reference to the drawings. The valve 10 is attached to a case 2 that houses a battery. The case 2 is mounted on, for example, a vehicle. As shown in FIG. 1, the case 2 is provided with an opening 2a that communicates with the inside and outside of the case 2. The opening 2a is provided to exhaust gas within the case 2 when the pressure within the case 2 becomes high. The valve 10 is attached to the opening 2a and opens and closes the opening 2a (more specifically, the gas exhaust port 4 described below).

[0028] The valve 10 includes a case mounting portion 6, a valve body 12, an elastic body 40, and a cover 42. The case mounting portion 6 fixes the valve 10 to the case 2 (more specifically, to the portion of the case 2 where the opening 2a is provided). The case mounting portion 6 includes a mounting portion 7 and a cylindrical portion 8.

[0029] The mounting portion 7 is disk-shaped and its outer shape is larger than the opening 2a of the case 2. The mounting portion 7 is arranged so as to cover the opening 2a. The outer periphery of the mounting portion 7 is arranged on the case 2. A circular opening is provided in the center of the mounting portion 7. The mounting portion 7 is fixed to the case 2 on its outer periphery side by fastening members 9 (e.g., screws, etc.).

[0030] The tubular portion 8 protrudes from the opening of the mounting portion 7 to the outside of the case 2 (upward in FIG. 1). The tubular portion 8 is cylindrical, and its cross-sectional area perpendicular to its axis is approximately constant. The end of the tubular portion 8 on the mounting portion 7 side is connected to the mounting portion 7, and the end on the outside of the case 2 is open. A gas exhaust port 4 is provided at the end of the tubular portion 8 on the outside of the case 2. By providing the gas exhaust port 4 at the end of the tubular portion 8, the gas exhaust port 4 protrudes to the outside of the case 2, and water is less likely to enter the gas exhaust port 4 when the case 2 is flooded.

[0031] The valve body 12 is made of metal and is arranged to open and close the gas discharge port 4. Specifically, the valve body 12 is closed when the pressure inside the case 2 is lower than a predetermined value, and opens when the pressure inside the case 2 is higher than the predetermined value. The valve body 12 is pressed toward the case 2 by an elastic body 40, as described later. Therefore, when the pressure inside the case 2 is lower than a predetermined value, the valve body 12 is in a closed state in which the gas discharge port 4 is blocked. On the other hand, when the pressure inside the case 2 is higher than a predetermined value, the valve body 12 is pressed toward the outside of the case 2 and is in an open state in which the gas discharge port 4 is opened. In this embodiment, the valve body 12 is made of metal, but is not limited to such a configuration. The valve body 12 may be made of resin, for example, as long as it can open and close the gas discharge port 4 according to the pressure inside the case 2.

[0032] As shown in Fig. 2, the valve body 12 includes a first portion 14, a second portion 16, a connecting portion 18, and a protrusion 20. In order to make the drawing easier to see, Fig. 2 omits illustration of the elastic body 40, the cover 42, and the second seal portion 62, and also omits illustration of the through hole 30 and the first auxiliary valve body 32 (described in detail later) in the first valve body.

[0033] The first portion 14 of the valve body 12 is in the shape of a substantially circular flat plate. The first portion 14 is disposed perpendicular to the axis of the cylindrical portion 8 and faces the cylindrical portion 8. The first portion 14 is larger than the gas discharge port 4, and completely covers the gas discharge port 4 when in contact with the gas discharge port 4 (for example, the state shown in FIG. 1).

[0034] The second portion 16 is disposed outside the valve body 12 relative to the first portion 14, and is located on the outer periphery of the valve body 12. The second portion 16 is annular and flat, and is disposed parallel to the first portion 14. The second portion 16 is disposed closer to the mounting portion 7 than the first portion 14. The second portion 16 is spaced apart from the mounting portion 7. Note that, although the second portion 16 is disposed parallel to the first portion 14 in this embodiment, the second portion 16 does not have to be parallel to the first portion 14.

[0035] The connection portion 18 connects the first portion 14 and the second portion 16. The connection portion 18 is disposed at an angle relative to the first portion 14 and the second portion 16.

[0036] In the valve body 12, in the closed state, only the area facing the inside of the case 2 through the gas discharge port 4 can receive the internal pressure of the case 2. Hereinafter, the area of ​​the valve body 12 facing the inside of the case 2 through the gas discharge port 4 in the closed state is referred to as the first pressure receiving surface 22, and the pressure received by the first pressure receiving surface 22 is referred to as the first pressure P1. The first pressure receiving surface 22 is provided in an area facing the gas discharge port 4 of the first portion 14.

[0037] The diameter of the valve body 12 is larger than the diameter of the gas discharge port 4. Therefore, the valve body 12 has a region around the first pressure receiving surface 22 that does not face the gas discharge port 4 when the valve body 12 is in a closed state. When the valve body 12 changes from a closed state to an open state, the region around the first pressure receiving surface 22 of the valve body 12 also receives the pressure of the gas discharged from the case 2. Hereinafter, the region around the first pressure receiving surface 22 of the valve body 12 is referred to as the second pressure receiving surface 24, and the pressure received by the second pressure receiving surface 24 may be referred to as the second pressure P2. The second pressure receiving surface 24 is provided in a region on the outer periphery side of the first pressure receiving surface 22 of the valve body 12. Therefore, the second pressure receiving surface 24 includes the pressure receiving surface of the region other than the first pressure receiving surface 22 of the first portion 14, the pressure receiving surface of the connection portion 18, and the pressure receiving surface of the second portion 16. The pressure acting on the second pressure-receiving surface 24 when the valve is open is much smaller than the first pressure P1 acting on the first pressure-receiving surface 22, and also decreases the further away from the gas discharge port 4. Therefore, on the second pressure-receiving surface 24, the first portion 14, the connection portion 18, and the second portion 16 receive the greatest pressure in this order when the valve is open.

[0038] In this embodiment, the valve body 12 has a first pressure receiving surface 22 and a second pressure receiving surface 24. By providing the valve body 12 with the first pressure receiving surface 22 and the second pressure receiving surface 24, when the valve body 12 changes from a closed state to an open state, the pressure inside the case 2 is received not only by the first pressure receiving surface 22 but also by the second pressure receiving surface 24. Therefore, when the valve body 12 opens, the area where the valve body 12 receives the pressure of the gas discharged from the gas discharge port 4 can be increased. Therefore, when the pressure inside the case 2 becomes high, the valve body 12 can be opened quickly. In addition, by providing the valve body 12 with the first pressure receiving surface 22 and the second pressure receiving surface 24, the gas discharged from the case 2 passes between the second pressure receiving surface 24 and the case 2 (specifically, the mounting portion 7 arranged on the case 2) and is discharged to the outside of the case 2. By forming such a discharge flow path, it becomes more difficult for gas discharged from the case 2 to flow into the opposite surface 26 of the valve body 12, compared to a valve body that does not have the second pressure-receiving surface 24. Therefore, when the pressure inside the case 2 increases, the pressure on the opposite surface 26 of the valve body 12 does not easily increase, and the valve body 12 can be opened quickly.

[0039] Fig. 3 shows the pressure (working pressure) acting on the first pressure-receiving surface 22 of the valve element 12 when the valve element 12 opens, and the valve opening degree (valve opening stroke) of the valve element 12. Graph A in Fig. 3 shows the valve element 12 having the first pressure-receiving surface 22 and the second pressure-receiving surface 24. Graph B shows, as a comparative example, a valve element having only the first pressure-receiving surface (i.e., a valve element having approximately the same size as the gas discharge port 4). Note that in the valve element of graph B, a pressure approximately equal to atmospheric pressure was applied to the surface of the valve element opposite to the pressure-receiving surface.

[0040] As shown in FIG. 3, both the valve body 12 of graph A and the valve body of graph B opened when the pressure acting on the first pressure receiving surface 22 became higher than a predetermined value a. In graph B of the comparative example, when the pressure acting on the valve body was higher than the predetermined value a, the valve body opened wider as the pressure acting on the valve body increased. On the other hand, the valve body 12 of graph A opened wider than the valve body of graph B when the pressure acting on the valve body 12 was between the predetermined value a and a pressure b that was somewhat higher than the predetermined value a. When the pressure acting on the valve body 12 was higher than the predetermined value a, the valve body 12 was open, and therefore the valve body 12 received the internal pressure of the case 2 not only at the first pressure receiving surface 22 but also at the second pressure receiving surface 24. Therefore, when the pressure acting on the valve body 12 was between the predetermined value a and a pressure b that was somewhat higher than the predetermined value a, the valve body 12 of this embodiment opened wider than the valve body of the comparative example.

[0041] The valve element 12 opens when the pressure inside the case 2 becomes higher than a predetermined value. For example, when the pressure inside the case 2 increases suddenly, it is necessary to reduce the pressure inside the case 2 quickly. For this reason, it is desirable for the valve element 12 to open quickly when opening. In particular, it is desirable for the valve element 12 to open quickly at the beginning of the valve opening. In this embodiment, the valve element 12 has not only the first pressure receiving surface 22 but also the second pressure receiving surface 24, so that the valve element 12 can be opened quickly when opening.

[0042] As shown in FIG. 1 and FIG. 2, the protrusion 20 is disposed on the outer periphery of the valve body 12 (i.e., the outer periphery of the second portion 16). The protrusion 20 is disposed over the entire circumferential direction of the valve body 12. The protrusion 20 protrudes toward the outside of the case 2. When the valve body 12 opens, gas in the case 2 is discharged to the outside of the case 2. The valve body 12 opens when pressed by gas discharged from the case 2. When the gas discharged from the case 2 moves to a surface 26 opposite to the pressure receiving surfaces 22, 24 of the valve body 12 (in FIG. 2, the upper surface of the valve body 12, hereinafter also referred to as the "opposite surface 26"), the pressure on the opposite surface 26 side of the valve body 12 increases, which may decrease the opening speed of the valve body 12. By providing the protrusion 20, the gas discharged from the case 2 is blocked by the protrusion 20 and is less likely to move to the opposite surface 26 side. Therefore, the decrease in the opening speed of the valve body 12 can be suppressed.

[0043] The projection 20 is provided with a drain hole 23. The drain hole 23 is provided in the projection 20 at a position near the second portion 16 of the valve body 12. The drain hole 23 is provided partially in the circumferential direction of the valve body 12. The valve body 12 may have at least one drain hole 23, and may have one or more. When the case 2 is flooded with water, water may enter the opposite surface 26 of the valve body 12. When water enters the opposite surface 26 of the valve body 12, the water accumulates on the second portion 16 due to the projection 20. By providing the drain hole 23, when the case 2 is flooded with water, the water that enters the opposite surface 26 of the valve body 12 can be discharged from the drain hole 23. The drain hole 23 also functions as an air hole (described later).

[0044] 1, the valve body 12 is provided with a through hole 30, and a valve element 32 is installed in the through hole 30. Hereinafter, the valve element 12 will be simply referred to as the "valve element 12", and the valve element 32 installed in the valve element 12 will be referred to as the "first auxiliary valve element 32". The through hole 30 extends from the first pressure-receiving surface 22 to the opposite surface 26 of the valve element 12. That is, the through hole 30 communicates between the inside and the outside of the case 2 when the valve element 12 is closed.

[0045] The first auxiliary valve body 32 is installed in the through hole 30. As shown in FIG. 4, the first auxiliary valve body 32 includes an insertion portion 34, a support portion 36, and a blocking portion 38. The insertion portion 34 is rod-shaped, and a cross-sectional area perpendicular to the axis is smaller than a cross-sectional area perpendicular to the axis of the through hole 30. The insertion portion 34 extends over the entire through hole 30, and both ends protrude from the through hole 30. The support portion 36 is connected to an end of the insertion portion 34 on the outside side of the case 2. The support portion 36 is disposed outside the case 2. The support portion 36 is spherical, and its diameter is larger than a cross section perpendicular to the axis of the through hole 30. The blocking portion 38 is connected to an end of the insertion portion 34 on the inside side of the case 2. The blocking portion 38 is disposed inside the case 2. The blocking portion 38 is plate-shaped, and is larger than a cross section perpendicular to the axis of the through hole 30. The outer periphery of the closing portion is curved towards the valve body 12. The closing portion is connected to the insertion portion at approximately the center.

[0046] The first auxiliary valve element 32 opens when the pressure in the case 2 is lower than a predetermined value, and closes when the pressure in the case 2 is higher than the predetermined value. When the pressure in the case 2 is lower than a predetermined value, the first auxiliary valve element 32 is positioned downward by its own weight and is supported by the valve element 12 by the support portion 36. When the first auxiliary valve element 32 is positioned downward, the blocking portion 38 is also positioned downward, and a gap is formed between the blocking portion 38 and the valve element 12. Therefore, gas can pass between the insertion portion 34 and the through hole 30, and between the blocking portion 38 and the valve element 12. That is, the state in which the first auxiliary valve element 32 is positioned downward is the open state. While the first auxiliary valve element 32 is in the open state, gas can pass through the through hole 30. Therefore, while the first auxiliary valve element 32 is in the open state, gas can move from the inside of the case 2 to the outside, and also from the outside of the case 2 to the inside, through the through hole 30. When the pressure inside the case 2 is lower than a predetermined value, the valve element 12 is closed. The pressure inside the case 2 may change due to environmental changes such as temperature. Since the first auxiliary valve element 32 is open when the pressure inside the case 2 is lower than a predetermined value, gas can move between the inside and the outside of the case 2 via the through hole 30 when the valve element 12 is closed. Therefore, the pressure inside the case is appropriately adjusted when the valve element 12 is closed.

[0047] When the pressure inside the case 2 becomes higher than a predetermined value, the blocking portion 38 receives the pressure inside the case 2, and the blocking portion 38 moves upward. As a result, the entire first auxiliary valve body 32 moves upward. Since the blocking portion 38 is larger than the cross-sectional area perpendicular to the axis of the through hole 30, when the first auxiliary valve body 32 moves upward, the blocking portion 38 blocks the through hole 30. Then, gas cannot move through the through hole 30. That is, the first auxiliary valve body 32 is in a closed state when it is located at the upper position. When the pressure inside the case 2 becomes higher than a predetermined value, the valve body 12 opens. If the through hole 30 is open even when the valve body 12 is open, gas is discharged from the through hole 30, and the pressure acting on the valve body 12 decreases. By closing the first auxiliary valve body 32 when the pressure inside the case 2 is higher than a predetermined value, it is possible to suppress a decrease in the pressure acting on the valve body 12 when the valve body 12 is open.

[0048] As shown in FIG. 1, the elastic body 40 is a spring, and is installed so as to press the valve body 12. One end of the elastic body 40 is attached to the second part 16 of the valve body 12 (specifically, the surface of the second part 16 opposite to the second pressure receiving surface 24), and the other end is attached to the inner surface of the cover 42. The elastic body 40 is installed so that its axis is approximately parallel to the axis of the gas discharge port 4. The elastic body 40 is compressed between the valve body 12 and the cover 42, thereby pressing the valve body 12 toward the gas discharge port 4. A plurality of elastic bodies 40 are arranged at intervals in the circumferential direction of the second part 16 of the valve body 12. The number of elastic bodies 40 provided in the valve 10 is not particularly limited.

[0049] In this embodiment, the elastic body 40 is attached to the second portion 16 of the valve body 12. Therefore, the elastic body 40 presses the second portion 16 toward the case 2, thereby pressing the valve body 12 toward the case 2. In order for the elastic body 40 to press the valve body 12 sufficiently, the elastic body 40 needs to extend over a certain range in the pressing direction. The elastic body 40 can press the valve body 12 on the case 2 side of the gas discharge port 4 by pressing the second portion 16 located on the case 2 side of the first portion 14. Therefore, the range in which the elastic body 40 extends from the gas discharge port 4 to the outside side of the case 2 can be reduced. Therefore, the size of the entire valve 10 can be prevented from increasing.

[0050] The cover 42 is disposed outside the case 2 relative to the valve body 12. As shown in FIG. 5, the cover 42 is circular when viewed along the axis of the gas discharge port 4, and is larger than the valve body 12. In FIG. 5, in order to make the drawing easier to see, a through hole 50 and a second auxiliary valve body 52, which will be described later, are omitted from illustration. The cover 42 opens toward the case 2, and is disposed so as to cover the entire valve body 12 (specifically, the opposite surface 26 opposite to the pressure receiving surface of the valve body 12). The cover 42 is supported by a support 44. The support 44 is disposed approximately parallel to the axis of the gas discharge port 4. One end of the support 44 is connected to the mounting portion 7, and the other end is connected to the outer periphery of the cover 42. The support 44 is disposed at intervals in the circumferential direction of the cover 42. Since the support 44 is disposed at intervals in the circumferential direction of the cover 42, a gap is formed between the cover 42 and the mounting portion 7 in the portion where the support 44 is not disposed. In this embodiment, three support columns 44 are installed, but the number of support columns 44 is not particularly limited as long as the support columns 44 can support the cover 42. The support columns 44 are fixed to the mounting portion 7 by, for example, screws or the like.

[0051] An end of the elastic body 40 is fixed to the inner surface of the cover 42 (the surface facing the valve body 12). When the pressing force of the elastic body 40 on the valve body 12 is higher than the pressure inside the case 2, the valve body 12 is pressed by the elastic body 40 and pressed against the gas discharge port 4. The valve body 12 is closed as a result of the valve body 12 being pressed by the elastic body 40. When the pressure inside the case 2 becomes higher than the pressing force of the elastic body 40 on the valve body 12, the valve body 12 is pressed toward the outside of the case 2 and the elastic body 40 is compressed. The compression of the elastic body 40 opens the valve body 12.

[0052] The cover 42 supports the elastic body 40 and covers the opposite surface 26 of the valve body 12. When the valve body 12 opens, gas in the case 2 is discharged from the gas discharge port 4. Since there is a gap between the cover 42 and the mounting portion 7, the gas discharged from the gas discharge port 4 passes through the gap between the cover 42 and the mounting portion 7 and is discharged to the outside of the case 2. The opposite surface 26 of the valve body 12 is covered by the cover 42. Therefore, a space 46 is formed by the opposite surface 26 of the valve body 12, the protrusion 20 of the valve body 12, and the inner surface of the cover 42. By forming the space 46, the gas discharged from the gas discharge port 4 is less likely to come into contact with the opposite surface 26 of the valve body 12. Therefore, even when the valve body 12 opens, the periphery of the opposite surface 26 of the valve body 12 can be maintained at a state that is approximately equal to the atmospheric pressure. Therefore, by providing the cover 42, it is possible to prevent the pressure around the opposite surface 26 of the valve body 12 from increasing due to the gas discharged from the gas exhaust port 4, and to prevent a decrease in the opening speed of the valve body 12.

[0053] FIG. 6 shows the flow rate (exhaust flow rate) of the gas discharged from the gas exhaust port 4 when the valve body 12 opens, and the pressure acting on the opposite surface 26 of the valve body 12 (hereinafter also referred to as back pressure). Graphs A and B in FIG. 6 show the back pressure on the valve body 12 of this embodiment (i.e., the valve body 12 having the first pressure receiving surface 22 and the second pressure receiving surface 24). Note that graph A shows the back pressure on the valve body 12 having the protrusion 20, and graph B shows the back pressure on the valve body 12 not having the protrusion 20. Graph C shows the back pressure of the valve body on a valve (for example, a valve described in JP 2020-194719 A) configured so that the entire amount of gas discharged from the case flows into the opposite surface of the valve body as a comparative example. As shown in FIG. 6, in graph C, the entire amount of the exhaust flow rate from the gas exhaust port 4 flows into the opposite surface, so that the back pressure also increases as the exhaust flow rate increases. On the other hand, in graphs A and B, even if the gas discharge flow rate from the gas discharge port 4 increases, the increase in back pressure is small, and in particular, the valve body 12 of graph A equipped with the protrusion 20 experienced almost no change in back pressure. Thus, in this embodiment, by providing the cover 42 and the protrusion 20, the back pressure does not increase, and a decrease in the valve opening speed of the valve body 12 can be suppressed.

[0054] 1, a through hole 50 is provided in the cover 42, and a valve body 52 is installed in the through hole 50. Hereinafter, the valve body 52 installed in the cover 42 will be referred to as the "second auxiliary valve body 52." The through hole 50 passes through the cover 42 from the inside to the outside.

[0055] The second auxiliary valve body 52 is installed in the through hole 50. As shown in FIG. 7, the second auxiliary valve body 52 includes an insertion portion 54, a blocking portion 56, and a stopper 58. The insertion portion 54 is rod-shaped, and a cross-sectional area perpendicular to the axis is smaller than a cross-sectional area perpendicular to the axis of the through hole 50. The insertion portion 54 extends over the entire through hole 50, and both ends protrude from the through hole 50. The blocking portion 56 is connected to an end of the insertion portion 54 on the outer side of the cover 42. The blocking portion 56 is disposed outside the cover 42. The blocking portion 56 is plate-shaped, and is larger than a cross-sectional area perpendicular to the axis of the through hole 50. In addition, the outer periphery of the blocking portion 56 is curved toward the cover 42. The blocking portion 56 is connected to the insertion portion 54 at a substantially center thereof. The stopper 58 is connected to an end of the insertion portion 54 on the inner side of the cover 42. The stopper 58 is disposed inside the cover 42. The stopper 58 is spherical, and its diameter is larger than the cross section perpendicular to the axis of the through hole 50 .

[0056] The second auxiliary valve element 52 closes when the pressure in the space 46 is lower than a predetermined value, and opens when the pressure in the space 46 is higher than the predetermined value. When the pressure in the case 2 is lower than the predetermined value, the valve element 12 is closed. At this time, since the volume of the space 46 is sufficiently large, the pressure in the space 46 becomes lower than the predetermined value, and the second auxiliary valve element 52 is positioned downward by its own weight. When the second auxiliary valve element 52 is positioned downward, the second auxiliary valve element 52 is supported by the blocking portion 56. In addition, the through hole 50 is blocked by the blocking portion 56. Therefore, the gas in the space 46 cannot pass through the through hole 50. That is, when the second auxiliary valve element 52 is positioned downward, the second auxiliary valve element 52 is in a closed state.

[0057] When the pressure in the case 2 becomes higher than a predetermined value, the valve body 12 opens and moves toward the cover 42. When the valve body 12 opens, the volume of the space 46 becomes smaller due to the valve body 12 that has moved, and the pressure in the space 46 becomes higher. Then, the gas in the space 46 moves into the through hole 50 and presses the blocking portion 56. When the pressure in the space 46 becomes higher than a predetermined value, the blocking portion 56 moves upward. When the blocking portion 56 moves upward, the entire second auxiliary valve body 52 moves upward until the stopper 58 abuts against the cover 42. When the second auxiliary valve body 52 moves upward, the gas in the space 46 that presses the blocking portion 56 through the through hole 50 is discharged directly to the outside of the cover 42. Therefore, when the pressure in the case 2 becomes higher than a predetermined value and the valve body 12 opens, the second auxiliary valve body 52 opens, and the gas in the space 46 can be discharged to the outside of the cover 42. That is, the second auxiliary valve element 52 is in an open state when it is in an upper position.

[0058] In this embodiment, by providing the cover 42 and the protrusion 20, a space 46 surrounded by the opposite surface 26 of the valve body 12, the cover 42, and the protrusion 20 is formed, and the gas discharged from the gas discharge port 4 can be prevented from flowing into the opposite surface 26 of the valve body 12. On the other hand, when the valve body 12 opens, the volume of the space 46 is reduced by the valve body 12, so that the pressure in the space 46 increases, and the pressure acting on the opposite surface 26 of the valve body 12 exposed to the space 46 increases. By providing the through hole 50 and the second auxiliary valve body 52 in the cover 42, the gas in the space 46 can be discharged when the valve body 12 opens. In addition, since the protrusion 20 is provided with the water drain hole 23, when the pressure in the space 46 increases, the gas in the space 46 is also discharged from the water drain hole 23. In this way, the gas in the space 46 is discharged when the valve body 12 opens, so that the pressure in the space 46 can be prevented from increasing when the valve body 12 opens. Therefore, when the valve body 12 is opened, it is possible to suppress a decrease in the pressure acting on the first pressure receiving surface 22 and the second pressure receiving surface 24 of the valve body 12. Since the protrusion 20 is provided with the drainage hole 23, it is not necessary to provide the second auxiliary valve body 52 on the cover 42.

[0059] Next, the flow path area of ​​the exhaust flow path of the gas exhausted from the gas exhaust port 4 will be described with reference to Fig. 8. In the following, the area of ​​the flow path formed between the end of the tubular portion 8 and the first portion 14 when the valve body 12 is opened is referred to as the "opening area D1", the area of ​​the flow path formed between the side surface of the tubular portion 8 and the connecting portion 18 is referred to as the "upstream area D2", and the area of ​​the flow path formed between the attachment portion 7 and the second portion 16 is referred to as the "downstream area D3".

[0060] As shown in FIG. 8, the valve body 12 is formed so that the upstream area D2 is larger than the downstream area D3 when the valve body 12 is closed (see FIG. 8(a)), and the upstream area D2 is equal to or smaller than the downstream area D3 when the valve body 12 is completely opened (see FIG. 8(c)). The valve body 12 is also formed so that the upstream area D2 is equal to or larger than the opening area D1 when the valve body 12 is completely opened. When the valve body 12 is formed as described above, the upstream area D2 is larger than the downstream area D3 during the period from the closed state of the valve body 12 to the predetermined range of opening (see FIG. 8(b)). When the valve body 12 is closed, the gap between the valve body 12 and the gas discharge port 4 is blocked, while a gap is formed between the valve body 12 and the attachment portion 7. When the valve body 12 is closed, gas outside the case 2 flows into the space 28 formed between the case 2 and the valve body 12 outside the case 2 through the gap between the valve body 12 and the attachment portion 7. Therefore, when the valve body 12 is closed, the pressure in the space 28 becomes substantially constant at atmospheric pressure.

[0061] When the valve body 12 opens, the gas in the case 2 is discharged from the gas discharge port 4. During the period from the closed state to the predetermined range of the valve body 12, the upstream area D2 is larger than the downstream area D3. The gas is more likely to enter the upstream area D2 side, which has a larger flow passage area, than the downstream area D3 side. For this reason, the gas moves more easily from the upstream area D2 side to the downstream area D3 side, and the gas discharged from the gas discharge port 4 easily flows into the space 28, while the gas is less likely to be discharged to the outside (atmosphere) side through the gap between the valve body 12 and the mounting portion 7. The gas discharged from the gas discharge port 4 enters the space 28, and the second pressure P2 acting on the second pressure receiving surface 24 tends to increase. During the period from the closed state to the predetermined range of the valve body 12, the gas discharged from the gas discharge port 4 enters the space 28 and the pressure in the space 28 increases, so that the valve body 12 can be opened quickly at the beginning of the valve opening.

[0062] Furthermore, when the valve body 12 is fully opened (see FIG. 8(c)), the opening area D1 ≦ upstream area D2 ≦ downstream area D3. That is, when the valve body 12 is fully opened, the area of ​​the flow path through which the gas discharged from the gas discharge port 4 to the outside of the case 2 flows increases from the upstream side to the downstream side. This makes it possible to reduce the resistance applied to the gas discharged from the gas discharge port 4 when it passes through the flow path with the opening area D1 and the upstream area D2 and flows into the flow path with the downstream area D3. This makes it possible to suppress a decrease in the flow rate of the gas discharged from the gas discharge port 4.

[0063] FIG. 9 is a diagram showing that the valve body 12 opens quickly in the initial stage of opening. Graphs A and B in FIG. 9 show the valve body 12 of this embodiment (i.e., the valve body 12 having the first pressure receiving surface 22 and the second pressure receiving surface 24). Note that in graph A, the upstream area D2 is not adjusted to be larger than the downstream area D3 when the valve body 12 is closed, and in graph B, the upstream area D2 is adjusted to be larger than the downstream area D3 when the valve body 12 is closed. Graphs C and D show a valve body having only the first pressure receiving surface (i.e., a valve body having approximately the same size as the gas discharge port 4) as a comparative example. Graph C is, for example, a valve body described in JP 2020-194719 A, and is configured so that the entire amount of gas discharged from the gas discharge port 4 flows into the surface opposite the pressure receiving surface of the valve body. In addition, graph D is configured so that a pressure approximately equal to atmospheric pressure acts on the surface opposite the pressure receiving surface of the valve body.

[0064] As shown in Figure 9(a), the valve disc 12 of graph A opened more widely than the valve discs of graphs C and D of the comparative examples when the pressure acting on the valve disc 12 exceeded a predetermined value. Also, the valve disc 12 of graph B opened even more widely than the valve disc 12 of graph A when the pressure acting on the valve disc 12 exceeded a predetermined value. This shows that the valve disc 12 of graph A opens quickly in the initial stage of opening of the valve disc 12, and the valve disc 12 of graph B opens even more quickly in the initial stage of opening of the valve disc.

[0065] Figures 9(b) to 9(d) show the relationship between the discharge flow rate of gas discharged from case 2 when the pressure inside case 2 exceeds a predetermined value, the opening degree of valve body 12, and the internal pressure (P1) and flow path pressure (P2) of case 2 versus elapsed time.

[0066] 9(b) and 9(c), in the early stage of valve opening, the valve element 12 of graph A quickly increases the discharge flow rate of gas discharged from case 2 compared to the valve elements of graphs C and D of the comparative examples, and the valve element 12 also quickly opens widely. Also, in the early stage of valve opening, the valve element 12 of graph B quickly increases the discharge flow rate of gas discharged from case 2 even more quickly than the valve element 12 of graph A, and the valve element 12 also opens widely.

[0067] Also, as shown in Figure 9(d), in the early stage of valve opening, the internal pressure (P1) of case 2 for the valve disc 12 of graph A dropped more quickly than for the valve discs of graphs C and D of the comparative examples. Also, in the early stage of valve opening, the internal pressure (P1) of case 2 for the valve disc 12 of graph B dropped even more quickly than for the valve disc 12 of graph A. In the early stage of valve opening, the flow path pressure (P2) was higher for the valve disc 12 of graph B than for the valve disc 12 of graph A. For this reason, the internal pressure (P1) of case 2 dropped more quickly for the valve disc 12 of graph B than for the valve disc 12 of graph A.

[0068] In addition, since the valve body 12 of the graph A and the valve body 12 of the graph B opened quickly, the peak of the internal pressure (P1) of the case 2 of the valve body 12 of the graph A was smaller than that of the valve bodies of the graphs C and D of the comparative example, and the peak of the internal pressure (P1) of the case 2 of the valve body 12 of the graph B was even smaller than that of the valve body 12 of the graph A. Therefore, the peak of the internal pressure (P1) of the case 2 of the valve body 12 of the graph A and the valve body 12 of the graph B was smaller than the allowable case internal pressure. On the other hand, the peak of the internal pressure (P1) of the valve body of the valve body of the comparative example of the graphs C and D exceeded the allowable case internal pressure. In this way, it was found that the valve body 12 of this embodiment (i.e., the valve body 12 of the graph A and the valve body 12 of the graph B) can open quickly when the pressure in the case 2 exceeds a predetermined value by opening quickly at the beginning of the valve opening, and damage to the case 2 can be avoided. In other words, it was found that by providing the valve body 12 with the second portion 16, the valve body 12 opens quickly at the initial stage of opening, and by adjusting the gas exhaust flow path from the case 2 as described above, the valve body 12 opens even more quickly at the initial stage of opening, making it possible to more reliably avoid damage to the case 2.

[0069] 1, the valve 10 includes a first seal portion 60 and a second seal portion 62. The first seal portion 60 is, for example, an O-ring, and is disposed around the entire circumferential direction of the gas discharge port 4 (i.e., the end of the cylindrical portion 8 on the outer side of the case 2). By disposing the first seal portion 60 at the gas discharge port 4, the gap between the valve body 12 and the gas discharge port 4 is sealed when the valve body 12 is closed. By sealing the gap between the valve body 12 and the gas discharge port 4 when the valve body 12 is closed, it is possible to prevent water from entering the case 2 from between the valve body 12 and the gas discharge port 4 even if the case 2 is flooded.

[0070] As described above, in this embodiment, the gas discharge flow path from the case 2 is adjusted so that the upstream area D2 is larger than the downstream area D3 when the valve body 12 is closed. As shown in Fig. 10, if the upstream area D2 when the valve body 12 is closed is larger than the downstream area D3, water will not enter the entire space 28 formed between the case 2 and the valve body 12 outside the case 2 even if the case 2 is flooded. This makes it possible to more reliably prevent water from entering the case 2 from between the valve body 12 and the gas discharge port 4 when the case 2 is flooded.

[0071] 1, the second seal portion 62 is, for example, a lip seal, and is disposed over the entire circumferential direction between the end of the valve body 12 (specifically, the second portion 16) and the attachment portion 7. By disposing the second seal portion 62, the gap between the valve body 12 and the attachment portion 7 is sealed when the valve body 12 is closed. By sealing the gap between the valve body 12 and the attachment portion 7 when the valve body 12 is closed, water is prevented from entering the space 28 in the event that the case 2 is flooded. This makes it possible to more reliably prevent water from entering the case 2.

[0072] In this embodiment, the cover 42 is larger than the valve body 12 when viewed along the axis of the gas discharge port 4, but is not limited to this configuration. For example, as shown in FIG. 11, the cover 242 may be smaller than the valve body 212 when viewed along the axis of the gas discharge port 4. That is, the protrusion 220 of the valve body 212 may be disposed outside the cover 242 when viewed along the axis of the gas discharge port 4. In this case, too, the gas discharged from the case 2 is blocked by the protrusion 220 and is difficult to move to the opposite side of the pressure receiving surface of the valve body 212, and is difficult to move to the opposite side of the pressure receiving surface of the valve body 212 by the cover 242. For this reason, it is possible to suppress the pressure on the opposite side of the pressure receiving surface of the valve body 212 from increasing, and to suppress a decrease in the opening speed of the valve body 212.

[0073] Example 2 In the above-mentioned first embodiment, the valve body 12 is covered by the cover 42, but the present invention is not limited to such a configuration. For example, the valve body 12 may not be covered by the cover 42, and the elastic body 40 may be supported by the support 142 instead of the cover 42. In this embodiment, the support 142 supporting the elastic body 40 is different from the cover 42 in the above-mentioned first embodiment, and the other configurations are substantially the same. Therefore, the description of the same configuration as the valve 10 in the first embodiment will be omitted. In addition, in FIG. 12, the protrusion 20, the through hole 30, and the first auxiliary valve body 32 of the valve body 12 are omitted, but the valve body 12 may include the protrusion 20, the through hole 30, and the first auxiliary valve body 32.

[0074] 12, the support 142 is disposed on the outer periphery side of the case 2 relative to the valve body 12. The support 142 is annular when viewed along the axis of the gas discharge port 4, and its outer periphery approximately coincides with the outer periphery of the valve body 12. The support 142 and the second portion 16 of the valve body 12 are spaced apart from each other, and an elastic body 40 is disposed between the support 142 and the second portion 16. One end of the elastic body 40 is attached to the second portion 16, and the other end is attached to the support 142.

[0075] The support 142 is supported by a support 144. The support 144 includes a support body 144a, a connection portion 144b, and a base 144c. The support body 144a is disposed substantially parallel to the axis of the gas discharge port 4. When viewed along the axis of the gas discharge port 4, the support body 144a is disposed outside the outer periphery of the valve body 12. The support body 144a extends from the attachment portion 7 to a height where the support 142 is located. The connection portion 144b extends from the end of the support body 144a opposite to the case 2 toward the support 142. The connection portion 144b connects the support body 144a and the support 142. The base 144c extends from the end of the support body 144a on the case 2 side toward the opposite side to the support 142. The base 144c is disposed on the attachment portion 7. The base 144c is fixed to the attachment portion 7 by, for example, a screw.

[0076] In this embodiment, the support 142 supports the elastic body 40 without covering the valve body 12. In this embodiment as well, since the valve body 12 has the second pressure-receiving surface 24, it is possible to increase the pressure-receiving area of ​​the valve body 12 when the valve body 12 is opened, and it is possible to open the valve body 12 quickly. In addition, since the elastic body 40 is disposed in the second portion 16, it is possible to prevent the size of the entire valve including the support body 142 from becoming large.

[0077] Example 3 In the above-mentioned first and second embodiments, the cylindrical portion 8 is provided on the case mounting portion 6 of the valve 10, but the present invention is not limited to such a configuration. For example, as shown in Fig. 13, the cylindrical portion 108 may be provided on the case 102. Note that the valve 110 of this embodiment differs from the valve 10 of the above-mentioned first embodiment in the configuration of the cylindrical portion 108, and other configurations are substantially the same. Therefore, a description of the same configuration as the valve 10 of the first embodiment will be omitted.

[0078] The valve 110 includes a valve body 12, an elastic body 40, and a cover 42. That is, the valve 110 differs from the valve 10 of the above-described first embodiment in that the valve 110 does not include a case mounting portion 6.

[0079] The case 102 includes a main body 105 that houses the battery, and a tubular portion 108 in which the gas exhaust port 4 is provided. The tubular portion 108 protrudes from the main body 105 to the outside of the case 102 (upward in FIG. 13). The tubular portion 108 is cylindrical, and the cross-sectional area perpendicular to its axis is substantially constant. The end of the tubular portion 108 on the side of the main body 105 is connected to the main body 105, and the end on the outside of the case 102 is open. The gas exhaust port 4 is provided at the end of the tubular portion 108 on the outside of the case 102. The valve body 12 is attached so as to open and close the gas exhaust port 4 provided in the tubular portion 108 of the case 102.

[0080] In this embodiment as well, a gas discharge port 4 is provided at the end of the cylindrical portion 108, and a valve body 12 is installed so as to open and close the gas discharge port 4 provided in the cylindrical portion 108. Therefore, it is possible to achieve the same effects as those of the above-mentioned embodiment 1.

[0081] In the above-mentioned Examples 1 to 3, the tubular parts 8 and 108 are cylindrical, but are not limited to such a configuration. For example, the tubular parts 8 and 108 may be cylindrical and polygonal when viewed along their axis. In the above-mentioned Examples 1 to 3, the valve body 12 is substantially circular, but are not limited to such a configuration. The valve body 12 may be capable of opening and closing the gas discharge port 4 provided at the end of the tubular parts 8 and 108, and the shape thereof is not limited. For example, the valve body 12 may be polygonal.

[0082] Points to note regarding the valve 10 described in the embodiment will be described below. The valve body 12 in the embodiment is an example of the "first valve body", the through hole 30 is an example of the "second through hole", the first auxiliary valve body 32 is an example of the "third valve body", the through hole 50 is an example of the "first through hole", and the second auxiliary valve body 52 is an example of the "second valve body".

[0083] Although specific examples of the present invention have been described above in detail, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and variations of the specific examples exemplified above. The technical elements described in this specification or drawings exhibit technical utility alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or drawings can achieve multiple objectives simultaneously, and achieving one of these objectives is itself technically useful. [Explanation of symbols]

[0084] 2, 102: Case 2a: Case opening 4: Gas outlet 7: Mounting part 8, 108: Cylinder part 10, 110: Valve 12, 212: Valve body 14: Part 1 16:Second part 18: Connection 20, 220: Protrusion 22: First pressure surface 24: Second pressure surface 30:Through hole of valve body 32: First auxiliary valve body 40: Elastic body 42, 242: Cover 50: Cover through hole 52: Second auxiliary valve body 60: First seal part 62: Second seal part 105: Main body of the case 142:Support

Claims

1. A valve attached to a case for opening and closing a gas exhaust port for exhausting gas inside the case to the outside of the case, the valve comprising: a first valve body that opens and closes the gas discharge port; an elastic body that presses the first valve body toward the gas discharge port; A support body that supports the elastic body, The first valve body is a first pressure receiving surface facing the inside of the case through the gas exhaust port; a second pressure-receiving surface located around the first pressure-receiving surface, the second pressure-receiving surface receiving the pressure of gas discharged from the gas exhaust port to the outside of the case when the first valve body is opened.

2. 2. The valve of claim 1, a valve including a flow path between the first valve body and the case, through which gas passes when the first valve body is opened and the gas is discharged from the gas discharge port to the outside of the case.

3. 3. A valve according to claim 1 or 2, the case has an opening communicating with the inside and the outside of the case, The valve further includes an attachment portion disposed around the opening and attached to the case, and a tubular portion protruding from the attachment portion to an outside of the case, The gas exhaust port is formed at a tip end of the cylindrical portion, The first valve body comprises a first portion facing the cylindrical portion and a second portion positioned around the first portion and closer to the case than the first portion.

4. 4. The valve of claim 3, a flow path through which gas flows to be discharged from the gas exhaust port to the outside of the case when the first valve body is opened, the area of ​​an upstream flow path formed between a side surface of the cylindrical portion and the first valve body is larger than the area of ​​a downstream flow path formed between the mounting portion and the first valve body during the period from when the first valve body is closed to when it opens to a predetermined range.

5. 4. The valve of claim 3, A valve in which, in a flow path through which gas flows to be discharged from the gas exhaust port to the outside of the case when the first valve body opens beyond a predetermined range from a closed state, when the area of ​​an open flow path formed between the upper surface of the cylindrical portion and the first valve body is D1, the area of ​​an upstream flow path formed between the side surface of the cylindrical portion and the first valve body is D2, and the area of ​​a downstream flow path formed between the mounting portion and the first valve body is D3, D1≦D2≦D3.

6. 3. A valve according to claim 1 or 2, The first valve body further includes a protrusion on an outer periphery thereof protruding outwardly from the case, The protrusion blocks the flow of gas discharged from the gas exhaust port to the outside of the case to the opposite side of the first pressure receiving surface of the first valve body and to the opposite side of the second pressure receiving surface.

7. 3. A valve according to claim 1 or 2, The support body includes a cover that covers a surface opposite to the first pressure receiving surface of the first valve body and a surface opposite to the second pressure receiving surface, The cover includes a first aperture extending through the cover.

8. 8. The valve of claim 7, The support body further includes a second valve body that opens and closes the first through hole, The second valve body closes when the pressure between the first valve body and the cover is lower than a predetermined value, thereby preventing gas from passing through the first through hole, and opens when the pressure between the first valve body and the cover is higher than a predetermined value, thereby allowing gas to pass through the first through hole.

9. 8. The valve of claim 7, The first valve body further includes a protrusion on an outer periphery thereof protruding outwardly from the case, the protrusion blocks a flow of gas discharged from the gas discharge port to the outside of the case toward the opposite side of the first pressure receiving surface of the first valve body and the opposite side of the second pressure receiving surface, The protrusion is disposed outwardly of the cover when viewed along the axis of the gas discharge port.

10. 3. A valve according to claim 1 or 2, The first valve body includes a second through hole extending from the first pressure receiving surface to an opposite surface thereof, and a third valve body opening and closing the second through hole, The third valve body opens when the pressure received by the first pressure-receiving surface is lower than a predetermined value, allowing gas to pass through the second through hole, and closes when the pressure received by the first pressure-receiving surface is higher than a predetermined value, preventing gas from passing through the second through hole.

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