JPS5822938Y2 - Lid for volatile liquid storage tank - Google Patents

Description

[Detailed description of the invention] The present invention aims to improve the lids of fuel storage tanks such as gasoline and kerosene, or organic solvent storage tanks, etc., and in particular, as the internal pressure of the storage tank gradually decreases as the stored fuel is used. The present invention relates to a lid body equipped with a negative pressure release mechanism that prevents the tank from being destroyed by decreasing the pressure and finally becoming negative pressure.

In general, the strength of airtight containers such as fuel storage tanks is said to be lower when the internal pressure is negative than when the internal pressure is greater than the external atmospheric pressure. In lid-type storage tanks, etc., an intake hole is provided in the tank itself or in the middle of the piping in order to prevent the tank from being destroyed by negative pressure, but vaporized stored fuel, etc. leaks into the atmosphere from the intake hole. It may be dangerous.

This invention immediately opens the storage tank to introduce outside air when the pressure inside the storage tank becomes negative, preventing the tank from being destroyed, and also seals the intake port to vaporize when the tank has positive pressure. The object of the present invention is to provide a lid for a volatile liquid storage tank that is equipped with a negative pressure prevention mechanism that can completely prevent leakage of fuel, etc.

The present invention will be explained below with reference to illustrated examples. In FIGS. 1 to 3, the lid 1 of the present invention, which is screwed or fitted into the opening of a storage tank (not shown), is attached to the top plate 1a. A negative pressure prevention valve fitting hole 2 for fitting a stem portion 7 of a negative pressure prevention valve 4 described later, and one or more (two in the illustrated example) ventilation pores 3, 3 are bored. ing.

In addition, in the figure, 10 is a backing fitted to the inner surface of the lid body 1.

The lid 1 of the present invention also includes a negative pressure prevention valve 4 that is in close contact with the inner surface of the top plate, as shown in FIG. A seal step portion 6 is integrally formed at the center of the concave surface of the sealing portion and protrudes from the concave surface; The negative pressure prevention valve 4 is made of, for example, oil-resistant acrylonitrile-butadiene copolymer rubber (selected depending on the required conditions). The insertion point 9, which is made of a rubber elastic body and is initially integrally formed at the distal end of the expanded diameter fitting part 8 of the stem part 7, is inserted into the negative pressure prevention valve fitting hole 2 of the lid body 1. By inserting the pointed end 9 into the outer surface of the top plate portion 1a of the lid body 1 and strongly pulling the pointed end 9, the subsequent enlarged diameter fitting portion 8 is also passed through the fitting hole 2, and thus the third As shown in the figure, the negative pressure prevention valve 4 is attached to the lid 1, and the insertion point 9 is removed.

The umbrella-shaped sealing part 5 of the negative pressure prevention valve 4 installed in the lid 1 is in close contact with the inner surface of the top plate part 1a of the lid 2, and the ventilation holes 3,
3, and the seal stepped portion 6 and the expanded diameter fitting portion 8 close the negative pressure prevention valve fitting hole 2 to prevent leakage of vaporized heat materials, etc. inside the storage tank to the outside.

When the fuel, etc. in the storage tank is gradually consumed and the internal pressure of the tank becomes negative, the umbrella-shaped sealing part of the negative pressure prevention valve 4 deforms so as to flip inward to the tank, as shown by the dotted line in FIG. 3. Since the ventilation holes 3, 3 are opened, external air is introduced through the holes, and the pressure inside the tank becomes equal to atmospheric pressure, and the negative pressure prevention valve 4 returns to the shape shown by the solid line in FIG. and lid body 1
All through holes 2 and 3 are closed.

As described in detail above, the lid for a storage tank of a volatile liquid such as gasoline, kerosene, or an organic solvent according to the present invention is a lid that is screwed or fitted onto an opening such as a liquid injection port of the storage tank. Ventilation pores are bored in the top plate of the body, and the top plate of the lid is in close contact with the inner surface of the top plate when the inside of the storage tank is at atmospheric pressure or positive pressure. to close the ventilation pores to prevent leakage of the vaporized stored liquid, and when the pressure inside the storage tank becomes negative than atmospheric pressure, the ventilation pores are opened to introduce outside air. The device is equipped with a negative pressure prevention valve made of rubber elastic material, which prevents accidents such as negative pressure inside the storage tank due to consumption of the stored liquid and the tank being destroyed, and also prevents volatile stored liquid from being released. Completely eliminates the risk of leakage outside the tank and causing poisoning or ignition/explosion accidents.

[Brief explanation of drawings]

FIG. 1 is an exploded perspective view of the lid of the present invention, FIG. 2 is a sectional view of a negative pressure prevention valve used in the lid of the present invention, and FIG. 3 is a partial sectional view of the assembled lid. 1... Lid body, 1a... Top plate part of the lid body,
2... Negative pressure prevention valve fitting hole, 3... Ventilation hole, 4... Negative pressure prevention valve, 5... Umbrella-shaped sealing part, 6...Seal step part, 7...Shaft part, 8...Bulging diameter fitting part, 9...Insertion tip part, 10... ··backing.

Claims (1)

[Scope of utility model registration request] On the inner surface of the top plate of the lid, which has a negative pressure prevention valve fitting hole and one or more ventilation holes,
an umbrella-shaped sealing part, a seal step part integrally formed at the center of the concave surface of the sealing part and protruding from the concave surface, and integrally formed from the seal step part along the central axis of the umbrella-shaped sealing part;
A negative pressure prevention valve constituted by a rubber elastic body, and a stem portion having a bulging diameter fitting portion formed at the tip thereof, and a negative pressure prevention valve configured by fitting the stem portion of the negative pressure prevention valve into the negative pressure prevention valve of the lid body. A lid for a volatile liquid storage tank that is tightly fitted by fitting into a matching hole.