JPH04171374A - Safety valve for pressure container - Google Patents

Abstract

PURPOSE:To secure the airtightness of a closing body under the normal temperature condition by allowing the closing body installed on the constitution wall of a pressure container to lead to the inner and outer surfaces, penetrating through a through hole, and by allowing the closing body to be equipped with a closing part which is closely attached on the inner and outer surfaces of the constitution wall. CONSTITUTION:A through hole 14 formal on a recessed part 13 formed on the bottom plate 11 of a pressure container 1 is closed by a closing body 3, and a rivet having a head part whose shape is previously set according to the shape of the recessed part 13 is used as closing body 13. In this case, the constitution material of the rivet is constituted of the low melting point alloy material, and the rivet is installed from the outer surface side of the bottom plate 11, and the shaft part 32 is allowed to penetrate through the through hole 14, and the shaft part 32 projecting to the inner surface side of the bottom plate 11 is caulking-fitted to constitute a closing body 3. In this case, the head part 31 forms the closing part on the outer surface side of the closing body 3, and a part the shaft part 32 which is formed flat by caulking forms the closing part on the inner surface side of the closing body 3.

Description

Detailed Description of the Invention [Field of Application and Summary of the Invention] The present invention relates to a safety valve for a pressure vessel, particularly a heat-sensitive safety valve that opens under abnormal heating conditions. A safety valve in which a through hole formed in a wall surface of a pressure vessel is closed by a closing body is intended to open reliably in the event of abnormal heating and to improve airtight performance in normal times. The manner in which the through hole is closed by the closing body is closed from both the inside and outside of the constituent wall.

In addition, the periphery of the closed portion on the inner surface side is covered with a synthetic resin coating layer to further improve the airtightness.

[Prior art and its problems] Patent application No. 2, No. 1999, relates to a safety valve in which a through hole formed in a wall of a pressure vessel is closed by a closing body made of a low melting point metal.
-46526 has already been proposed.

As shown in FIG. 6, this has a concave part (1
3) and a through hole (13) in the center of this recess (13).
4) is formed through the bottom plate (11), and the through hole (10) is closed and vaporized from the outer surface side of the bottom plate (11) by a closing body (3) made of a low melting point metal.

In this case, the melting point of the closing body (3) is set at a predetermined temperature, so if the pressure vessel (1) is left under abnormal temperature conditions, the closing body (3) will melt and become transparent. Hole (1
4) is opened, the pressure inside the pressure vessel (1) is reduced, and accidents such as explosions can be prevented. Furthermore, such a heat-sensitive safety valve can be realized with a simple configuration.

However, in this case, the through hole (14) due to the closure body (3)
Depending on the state of occlusion, the airtightness during occlusion may be insufficient. This is because if the through hole (14) is simply closed off from the outer surface side of the constituent wall of the pressure vessel (1) with the closing body (3), there remains a possibility of leakage.

The present invention has been made in view of this point, and the through hole (14) formed in the constituent wall of the r pressure vessel (1) is made of a low melting point metal closure body ( 3)
The objective of the heat-sensitive safety valve is to ensure airtightness in the closed state.

11 [Technical Means] The technical means of the present invention taken to solve the above problem is to connect the closure body (3) attached to the constituent wall of the pressure vessel (1) to the through hole (14). ) to reach both the inner and outer surfaces of the component wall, and the closure body (3) is provided with a closure portion that comes into close contact with both the inner and outer surfaces of the component wall.

[Effect] The above technical means of the present invention operates as follows.

The closure body (3) has a through hole (14) through the constituent wall of the pressure vessel (1).
), and the closing portions provided on both the inner and outer surfaces of this constituent wall close the entire outer periphery of the periphery of the through hole (14).

Therefore, the through hole (14) has a closure body (3) passing through it.
It is closed by the constituent materials, and is also closed by the closing part that is in close contact with both the inner and outer surfaces. In other words,
The through hole (14) formed through the constituent wall of the pressure vessel (1) is triple-occluded by the inner and outer closing portions and the constituent material filled in the through hole (14).

Furthermore, since the melting point of the closing body (3) is set to a predetermined temperature, if the pressure vessel (1) is placed under abnormal heating conditions, the closing body (3) will melt due to the temperature at this time. The through hole (14) opens and the internal pressure of the pressure vessel (1) is reduced.

[effect] Since the present invention has the above configuration, it has the following unique effects.

Since the through hole (14) is triple-occluded by the closing body (3) made of a low melting point metal, the airtightness of the closing body (3) under normal temperature conditions is ensured.

11 kodan or 1 ri This invention of claim 2 specifies the structure of the constituent wall of the pressure vessel (1) in the invention of claim 1, and the closure body (3)
The aim is to further improve the airtightness of the through hole (14) in a state where the through hole (14) is closed. The inner surface of the wall was covered with a synthetic resin M (2), and an opening (21) was formed in this synthetic resin layer (2) at a location corresponding to the center of the closed portion on the inner surface side of the closing body (3). One thing.

By adopting this configuration, the outer peripheral area of the opening (21) closes the joint between the closing part of the closing body (3) and the constituent wall of the pressure vessel (1), further improving airtightness in normal times. improves.

In addition, since the synthetic resin layer (2) is provided with an opening at a location that corresponds to the center of the closed part of the closure body (3), the closure body (3) melts and the through hole (14) opens. In this case, the inside and outside of the pressure vessel (1) are in communication with each other, and the synthetic resin layer (2) does not become an obstacle to safe operation.

[Example] Hereinafter, an example of the present invention will be described based on FIGS. 1 to 5.

look! The embodiment shown in FIG.
The through hole (work 4) of the recessed part (13) formed in the blocker (3)
), and in this embodiment, as shown in FIG. 2, it is provided with a head (31) having a shape set in advance to match the shape of the recess (13). A rivet is used as a closure (3).

In this device, the constituent material of the rivet is a low melting point alloy material, and the rivet is attached from the outer surface side of the bottom plate (11), and its shaft portion (32) is passed through the through hole (14). Then, the shaft portion (32) protruding from the inner surface of the bottom plate (11) is caulked to form the closure body (3) as shown in FIG. In this case, the head (31) becomes a closure part on the outer surface side of the closure body (3), and a part of the shaft part (32) flattened by caulking becomes a closure part on the inner surface side of the closure body (3). Become.

The pressure vessel (1) of this embodiment is an aerosol container, and the bottom plate (11) is caulked to the open lower end of the body of the pressure vessel (1), and the contents are filled and the valve device (v) It is used by attaching it to the lid plate (lO).

In addition, in this example, the closure body (3) is the pressure vessel (1).
Although this closure body (3) is provided on the bottom plate (11) as a constituent wall, it may be provided on other constituent walls, such as the lid plate (1G) or the body of the pressure vessel (1). .

This embodiment corresponds to the invention of claim 2 above,
As shown in FIG. 3, a bottom plate (11) whose inner surface is coated with a synthetic resin layer (2) is used.

A metal plate material provided with this synthetic resin layer (2) is punched out in advance into a blank of a predetermined shape, and then bent into a predetermined cross-sectional shape by drawing. At this time, the concave portion (13)
and a through hole (14). When forming the through hole (14), the synthetic resin layer (2) is also punched out at the same time, so the portion corresponding to the through hole (14) becomes the opening (21).

In this embodiment, the recess (13) is spherical, the diameter of the recess (13) is set to approximately 511II11~8+nm, and the through hole (14) bored in the center has a diameter of 0.5 mm. It is about 2.0 ■. A low melting point alloy is melted and bonded to cover substantially the entire bottom wall of this recessed portion (13) to form a closed body (3). At this time, the weight of the low melting point alloy is approximately 0.6 g to 1.6 g, and the thickness of the low melting point alloy is 0.5 mm.

The melting point of this low melting point alloy is 9 in this example.
The temperature is set at 5°C to 180°C, but preferably 100°C.
Set the temperature to 150°C. Depending on the usage conditions of the sealed container, it is also possible to set the temperature lower or higher than this temperature.

In order to melt and bond the low melting point alloy to the bottom plate (11) used in the container of the above embodiment, a method as shown in FIG. 4 is adopted.

Note that it is natural that the melting point of the synthetic resin layer (2) is higher than that of the closure body (3), but this synthetic resin layer (
The softening point of step 2) is also set higher than the melting point of the closing body (3). For example, if the melting point of the closing body (3) is set at 100°C to 150°C as described above, the synthesis As the resin layer (2), one made of epoxy-phenol resin can be used.

In this method, a conveyor (41) is disposed so as to pass through the heating furnace (4), and a pellet (P ) is located in the hopper (42). In addition,
The size of each pellet (P) is commensurate with the above weight.

On the conveyor (41), support stands (43) (43) that support the bottom plate (11) in a downwardly convex posture are successively arranged at predetermined intervals, and each support stand (43) The bottom plate (11) is placed on the conveyor (41) and the conveyor (41) is run at a predetermined speed.

A pellet (P) is placed at the outlet of the hopper (42).
A loading device (5) for dropping the (P) one by one is provided, and this immersion device (5) operates at a predetermined timing based on the output from the detection device (51) that detects the bottom plate (11).

Therefore, when this detection device (51) detects that the bottom plate (11) is located below the outlet of the hopper (42),
The output at this time operates the feeding device (5) to drop one pellet (P) from the hopper (42), and as the conveyor (41) travels, the bottom plate (11) is moved below the hopper (42). The above operation is repeated each time the camera is located at .

The pellet (P) thrown into the bottom plate (11) by the above procedure is not exactly thrown into the recess (13), but the bottom plate (11) is supported by the support stand (43) (43). In the supported position, since the upper surface side is concave (spherical), the pellet (P) inserted into the bottom plate (11) is reliably located in the recess (13).

Moreover, since this concave part (13) is also concave (spherical), the pellet (P) located inside this concave part (13)
coincides with the through hole (14) located in the center of this.

In this way, the bellet (
P), each bottom plate (11) is moved to the conveyor (41
) is fed into the heating furnace (4) as it travels, the atmospheric temperature in the heating furnace (4) is set higher than the melting point of the low melting point alloy. Since the length of 4) is set to a predetermined value, the pellet (P) accommodated in the concave portion (13) passes through the heating furnace (4).
is melted and diffused onto the bottom wall of the recess (13).

In particular, in this embodiment, the temperature in the heating furnace (4) is set higher than the softening point of the synthetic resin layer (2) and lower than the melting point of the synthetic resin layer (2). Therefore, the molten alloy melted and diffused on the bottom wall of the concave portion (13) as described above also flows out to the back side of the bottom plate (11) through the through hole (14) and connects to the synthetic resin layer (2) on the back side and the bottom plate. (11) and the metal layer constituting the bottom plate (11), as shown in Figure 5.
) is constructed such that the periphery of the closed portion on the back side is covered with the synthetic resin layer (2).

Although the principle of penetration of this molten alloy has not been elucidated, under conditions where the synthetic resin layer (2) is heated to an abnormally high softening point temperature, the metal layer and the synthetic resin layer ( It is thought that the bond with 2) is weakened and the molten alloy enters the boundary from that part. In the case where the synthetic resin layer (2) is made of epoxy-phenol resin, when the ambient temperature in the heating furnace (4) is around 250°C, the molten alloy is mixed with the metal layer and the synthetic resin! (2)
There was a moderate amount of intrusion between the two.

In this embodiment, an air cooling device (6) is provided downstream of this heating furnace (4), and while passing through this, a concave portion (1) is provided.
The low melting point alloy diffused and melted at the bottom of 3) hardens and is fused and bonded to the front and back sides of the bottom wall of the recessed part (13) to form a closing body (3), and the through hole (4) is closed. Ru.

When the bottom plate (11) with the through hole (14) closed with a low melting point alloy is caulked to the open lower end of the container main pressure vessel (1), a sealed container is completed.

In the case of an aerosol container, a high-pressure gas is sealed in the sealed container, and the operation of filling the high-pressure gas is carried out by a known method. In addition, in some cases, the bottom plate (11)
A valve body for sealing the high-pressure gas body may be separately provided at the bottom of the valve body.

When using a special high-pressure gas filling device, such as when filling a high-pressure chamber with liquefied gas and caulking the bottom plate,
The valve body for filling the high-pressure gas is not required.

As the low melting point alloy used in the above embodiments, various known alloys can be used. For example, solder can be used. still,
Bismuth is an example of this type of alloy.

An alloy of lead and tin is commonly used, and various melting points can be set by changing the ratio of each component. For example, alloys that melt at temperatures as low as 50° C. can also be manufactured.

In the above embodiment, the safety valve of the present invention is provided at the bottom of the aerosol container, but it goes without saying that the safety valve of the present invention can be employed in other types of sealed containers. 11) does not necessarily have to have an inwardly convex cross-sectional shape.

Furthermore, in the invention of claim 2, if the bottom plate (xi) has a shape such as a conical shape in which the central part gradually projects inward from the outer peripheral part, the bottom plate (11) does not necessarily have a spherical shape. do not have to. There is no need for the recessed portion (13) to be approximately spherical.

Furthermore, the pellets (P) may be added manually, or the low melting point alloy may be hardened by natural cooling without using the air cooling device (6). Furthermore, it goes without saying that the present invention can be used in various containers other than the aerosol container of the above embodiment. Further, the present invention can also be applied to a type of container in which the inner surface of the body of the main body (1) of the container is also coated with a synthetic resin layer.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the first embodiment of the present invention, and FIG. 2 is a bottom plate (
11), and FIG. 3 is a detailed view of the main parts of the bottom plate (1) of another embodiment.
1), FIG. 4 is an explanatory diagram of the manufacturing method of the bottom plate (11) of the safety valve material of this sealed container, FIG. 5 is an enlarged view of the main part of the second embodiment, and FIG. 6 is the safety valve of the prior art. It is an explanatory diagram of
In the figure. (1)...Pressure vessel (14)...Through hole (3)...Closing body (2)...Synthetic resin layer (21)...Opening

Claims (1)

[Claims] [1] A through hole (14) formed in the constituent wall of the pressure vessel (1).
) is closed by a closing body (3) made of a low melting point metal whose melting point is set at a predetermined temperature.
) is passed through a through hole (14) to reach both the inner and outer surfaces of the constituent wall, and the closing body (3) is provided with a closing portion that is in close contact with both the inner and outer surfaces of the constituent wall. [2] The inner surface of the constituent wall of the pressure vessel (1) equipped with the closure body (3) is coated with a synthetic resin layer (2), and this synthetic resin layer (2) includes the composition of the closure body (3). The safety valve for a pressure vessel according to claim 1, wherein the opening (21) is formed at a location corresponding to the center of the closed portion on the inner surface side.