JPH028136Y2 - - Google Patents

Description

[Detailed explanation of the idea] This invention relates to a pressure chamber sealing device.

A heat medium or other fluid may be sealed in a pressure chamber such as a heat pipe or pressure vessel.
In that case, if the filling hole is sealed by pressure welding, brazing, welding, etc.
Although a high degree of airtightness can be ensured, it is not easy to open and is extremely difficult to reseal. In addition, a screw-in type structure consisting of a combination of a taper screw and a taper plug is sometimes used to seal the filling hole, but this makes opening and resealing easy, but does not ensure a high degree of airtightness. Particularly in the case of heat pipes, microbreathing takes place between the inside and the outside, making it impossible to maintain a high internal vacuum, resulting in significant deterioration of the heat pipe's operating characteristics over time.

This idea allows the sealing hole of the pressure chamber to be easily opened while maintaining a high degree of airtightness. The seal can be resealed freely, and when the temperature inside the pressure chamber rises above a predetermined value, the airtightness is released to prevent damage to the pressure chamber. The purpose is to prevent explosions.

An embodiment of this invention will be described with reference to the drawings. In the figure, 1 is a pressure chamber such as a heat pipe, and 2 is an inlet port thereof, in which an inlet hole 3 communicating with the inside of the pressure chamber is provided, and a screw hole 4 is provided on the outside continuously from the inlet hole 3. There is. A set screw 5 is composed of a screw body 6 and a ball-shaped valve 7 made of steel, for example. A through hole 8 is formed in the center of the screw body. A valve 7 is fixed to the opening surface of the lower end of the hole 8 so as to close it.
The valve 7 has a hole 9 formed through its axis, and a molten metal (or alloy) 1 that melts at a predetermined temperature is inserted into the hole 9.
Filled with 0s. The valve 7 is then fixed to the screw body 6 as described above so that the hole 9 is aligned with the through hole 8 of the screw body 6.

In the above configuration, after the inside of the pressure chamber 1 is evacuated and a required fluid such as a heating medium is injected, the sealing port 2 is sealed with a set screw 5. This sealing can be accomplished by simply screwing the threaded portion 6A on the outer periphery of the screw body 6 into the threaded hole 4 of the sealing opening portion 2. For screwing, for example, a polygonal (hexagonal in the illustrated example) square hole 6B may be provided inside the screw body 6, and a tool may be inserted into the hole 6B for screwing.

By screwing in the screw body 6, the valve 7 comes to be pressed against the upper opening surface of the filling hole 3 of the filling port portion 2. This upper end opening surface acts as a valve seat, but by finishing this upper end opening surface and the valve 7 sufficiently smoothly, airtightness can be maintained reliably by sufficiently screwing the screw body 6. will be done. Since it is sealed with screws like this, it cannot be opened. Needless to say, resealing is easy. In the position where the sealing hole 3 is closed by the valve 7, the opening surface of the lower end of the hole 9 faces the sealing hole 3.

During use, if the temperature within the pressure chamber 1 rises above the melting temperature of the molten metal 10, the molten metal 10 will be melted by the heat generated at that time. The molten metal 1 melted by the pressure inside the pressure chamber 1
0 flows out from the hole 9 through the through hole 8, and as a result, the through hole 8 and the sealing hole 3 communicate with each other through the hole 9. Through this communication, steam within the pressure chamber 1 is released to the outside. This caused damage to pressure chamber 1. This will prevent explosions.

As understood from the above explanation, the high temperature inside the pressure chamber 1. Damage caused by high pressure. Since the purpose is to prevent explosions, the molten metal 10 to be used should have a melting temperature that does not exceed the maximum allowable operating temperature of the pressure chamber. good.

FIG. 4 shows a configuration in which this invention is applied to a heating medium-filled induction heating roller device. A shaft 12 is connected to the roller body 11, and a bearing 13
It is rotatably supported with respect to the machine base 14 by. An induction coil 16 and an iron core 17 (fixed shaft 1
A part of 5 may also be used. ) is supported, and when the induction coil 16 is excited by an AC power source via a conductor 19,
A current is induced in the peripheral wall portion 11A of the roller body 1, and the peripheral wall portion 11A generates heat due to this current.

The temperature of the peripheral wall portion 11A is detected by a temperature sensor 20. That is, the voltage induced in the temperature sensor 20 is led to the outside via the lead 21, the slip ring 22, and the brush 23. The surface temperature of the peripheral wall portion 11A is maintained at a desired value by adjusting the voltage of the induction coil 16 according to the detected temperature.

An airtight jacket chamber 23 is installed within the thick wall portion of the peripheral wall portion 11A, and a gas-liquid two-phase heating medium 24 such as water or oil is sealed therein. It is already well known that the entire area of the peripheral wall 11A is temperature-equalized by the movement of latent heat due to the phase change of the heating medium, and a uniform temperature distribution can be obtained.

However, if the temperature control of the rollers is not performed smoothly due to a failure of the temperature sensor 20, voltage regulator, etc., the roller temperature will rise abnormally, causing the heating medium 23 to reach a high temperature, and eventually the jacket chamber 22 and even the It is also possible that the roller body 11 breaks or explodes.

To prevent this, a sealing device according to this invention is installed in the jacket chamber 23 as shown in the figure. That is, a hole communicating with the outside air may be provided in a part of the jacket chamber 23, and this hole may be used as the sealing hole 3 shown in FIG. 1, and a set screw 5 may be installed therein as shown in the figure.

To explain the sealing device actually manufactured by the present inventor, the diameter of the sealing hole 3 is 3.5 mm, and the diameter of the valve 7 is 4.7 mm.
mm, the diameter of the hole 9 at the center is 1.0 mm, the molten metal is an alloy of lead and silver, and the melting temperature is approximately 304℃.
And so. In this configuration, when the jacket chamber was at an abnormally high temperature (approximately 302 DEG C.), the molten metal melted and the steam inside the jacket chamber was discharged to the outside through the valve 7 and hole 8.

As detailed above, according to this invention, sealing, unsealing, and resealing of the sealing port of the pressure chamber is extremely easy due to the screw-in method, and in the event of an abnormality, the pressure chamber communicates with the outside air, so there is no possibility of damage or damage. This has the effect of reliably preventing the occurrence of abnormal conditions that may lead to explosions.

[Brief explanation of drawings]

Figure 1 is a sectional view showing an embodiment of this invention, Figure 2 is a sectional view showing an embodiment of this invention.
The figure is an exploded sectional view, Figure 3 is a plan view of the set screw,
FIG. 4 is a sectional view showing an example of the use of this invention, and FIG. 5 is a partially enlarged sectional view. DESCRIPTION OF SYMBOLS 1... Pressure chamber, 2... Filling port part, 3... Filling hole, 4... Screw hole, 5... Set screw, 6... Screw body, 7... Valve, 8... Through hole, 9... ...hole, 10
...molten metal.

Claims (1)

[Scope of utility model registration request] A sealing hole that communicates with outside air is provided in the sealing port of the pressure chamber,
A screw hole is provided that is continuous with the sealing hole, and a set screw is constituted by a screw body having a through hole and a ball-shaped valve fixed to the opening surface of the lower end of the through hole. A hole is provided in line with the hole, the hole is filled with molten metal, and the screw body is screwed into the screw hole so that the valve closes the filling hole, and the closed position A sealing device for a pressure chamber in which a lower end opening surface of the hole filled with the molten metal faces the sealing hole.