JPH0649518B2 - Pressure difference relief type container - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a container, such as a container, which is used particularly for transportation of a product which is not sensitive to moisture, for example, transportation of a large computer or the like, or storage of the same.

(Prior Art) For example, there is a container as a representative of the containers for transportation or storage.

3 and 4 show the outline of a conventional container of this kind. The container shown in FIG. 3 adopts a completely closed system, and is robustly manufactured so as to prevent outside air from entering and sufficiently withstand the pressure difference between the inside and the outside. Therefore, in this completely sealed system container, since the pressure difference between the inside and the outside is supported by the strength of the container itself, it is unavoidable to increase the weight of the container itself, and it is also necessary to sufficiently improve the processing accuracy. However, there is a drawback that it is not possible to wipe out the difficulties in handling and cost.

On the other hand, the container shown in FIG. 4 is equipped with a pressure control valve 1 on the wall thereof, and when the pressure difference between the inside and outside exceeds a certain value, the valve is opened to let gas flow from the high pressure portion to the low pressure portion to balance the internal and external pressures. Is designed. Then, for example, when the outside air pressure greatly exceeds the pressure inside the vessel, the control valve 1 is actuated to allow the outside air to enter the container, and the inside and outside pressures are balanced. A storage box 2 in which a desiccant for absorbing is stored is installed in the container. In the container of the system shown in FIG. 4, due to the presence of the pressure control valve 1, the strength of the container itself is sufficient to withstand the pressure within the working pressure of the pressure control valve 1, and the completely sealed container However, the desiccant needs to be replaced according to the situation, and it is necessary to perform regular inspection for that. If the operating pressure of the pressure control valve is increased with the delay of this periodic inspection, the strength of the container will have to be increased and the weight will increase.

(Problems to be Solved by the Invention) The present invention improves a conventional container having a pressure control valve and a desiccant, in which the weight of the container is inevitably increased if the period of the regular inspection is extended. Therefore, it is intended to provide a pressure difference relaxing type container capable of extending the periodic inspection period and suppressing the container strength to a necessary minimum and reducing the weight.

(Means for Solving the Problems) Therefore, the present invention provides a pressure difference relaxation type container in which a desiccant is disposed inside a pressure control valve that operates when the pressure difference between the inside and the outside exceeds a certain level. A part of the container is provided with a bellows that communicates with the inside of the container and that expands and contracts according to the difference in internal and external pressures, which is a means for solving the problem.

(Operation) Even if a bellows or a bladder tank is used as the expansion / contraction member, and the operating pressure of the pressure control valve is set low, the bellows or the bladder tank expands or contracts to produce a differential pressure. ease. The pressure control valve will not operate if the pressure difference is below a certain level even if the bellows expands / contracts, but will not operate until the pressure difference exceeds a certain level, at which time the moisture in the air that enters the container Absorbed by desiccant. Therefore, the bellows takes part of the strength of the container, which reduces the number of times the pressure control valve is operated, and as a result, the desiccant replacement period can be extended.

(Example) Hereinafter, an example of the present invention is described based on an accompanying drawing.

FIG. 1 shows an outline of a container which is an embodiment of the present invention, and
The operating principle of the expansion / contraction member is shown in the figure.

In the figure, 1 is a pressure control valve, 2 is a desiccant storage box,
These are the same as the conventional container shown in FIG. 4, but in this embodiment, a bellows 3 is continuously provided as a part of the container. Although the bellows 3 is illustrated in the illustrated example, a bladder tank can be used instead of the bellows.

FIG. 2 schematically shows the principle of operation of the container according to the present invention. Reference numeral 4 is a cylinder, 5 is a piston that freely slides in the cylinder 4, and the external pressure p _out is now greater than the internal pressure p _in . is greater, the piston 5 moves in the cylinder 4 to the left in the figure, to rest at a position where the pressure difference between inside and outside (p _out -p _in) becomes zero.

In the embodiment of FIG. 1, it can be considered that the container body corresponds to the cylinder and the bellows 3 corresponds to the piston.

Therefore, when the external air pressure rises and exceeds the pressure in the container, the bellows 3 contracts by the pressure difference, and the pressure difference between the internal pressure and the external pressure is relaxed. When this pressure difference exceeds the range in which the bellows can be relaxed, the pressure control valve 1 is operated for the first time. This operating pressure can be set lower than that of a container in which the bellows are not connected in series, and the number of times the pressure control valve 1 is operated can be reduced even if the operating pressure is set low. As a result, the moisture absorption amount of the desiccant is reduced, and the replacement period can be extended.

(Effect of the Invention) As described in detail above, the present invention is provided with the pressure control valve that operates when the internal / external pressure difference exceeds a certain level and the bellows that expands / contracts according to the internal / external pressure difference. It is possible to relieve a part of the pressure by the bellows, and the pressure control valve will not operate if the pressure difference is below a certain level even if the bellows expands and contracts, but it will not operate until the pressure difference exceeds a certain level. However, the moisture in the air that enters the container at this time is absorbed by the desiccant. Therefore, the bellows takes a part of the strength of the container, which reduces the number of times the pressure control valve is operated, and as a result, the desiccant and the replacement period can be extended.

[Brief description of drawings]

FIG. 1 is a sectional view of a pressure difference moderating container schematically showing an embodiment of the present invention, FIG. 2 is a schematic sectional view showing the operating principle of the container, and FIG. 3 is a conventional completely sealed container. Schematic sectional view, 4th
The figure is a schematic sectional view of a conventional pressure control valve / container with a desiccant. Description of main parts of the figure 1 …… Pressure control valve 2 …… Drying agent storage box 3 …… Bellows

Claims (1)

[Claims] 1. A pressure difference relaxation type container having a pressure regulating valve which operates when the internal and external pressure difference exceeds a certain level, and a desiccant disposed therein, which is a part of the container and is provided inside the container. A pressure difference relaxing container characterized in that it is provided with a bellows that communicates with each other and expands and contracts according to a pressure difference between the inside and the outside.