JPH06156506A - Portable storage tank - Google Patents

Abstract

PURPOSE:To securely let the liquid pool of a storage tank for a chemical solution like a developing liquid used for a production process of LSI to coincide with the lower end of the liquid delivery pipe. CONSTITUTION:A short gas supplying pipe 6 and a long liquid delivery pipe 7 are inserted in an eccentric position of the upper face 1a of a tank body 1. And seats 6a, 7a are attached to the end protruded from the upper face 1a of the gas supplying pipe 6 and the liquid delivery pipe 7. On the other hand, the bottom face of the tank body 1 is slanting toward one side and a liquid pool is formed at the lowest position. The liquid pool is formed right under the liquid delivery pipe 7 and the lower end of the linear liquid delivery pipe 7 is extended to the liquid pool.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a portable storage tank capable of storing a chemical solution such as a developing solution used in an LSI manufacturing process and taking out a required amount thereof.

[0002]

2. Description of the Related Art Japanese Patent Application Laid-Open No. Sho 5 (1994)
Some are disclosed in Japanese Patent Publication No. 9-21021. This tank is equipped with a cap that closes the liquid injection opening on the upper surface of the airtight tank body, and the pressurizing gas supply pipe and liquid withdrawal pipe are passed through this cap, and the lower end of the liquid withdrawal pipe is close to the bottom of the tank. Extend the gas supply pipe so that its lower end is located above the liquid to be stored,
The pressure of the gas supplied into the tank through the gas supply pipe causes the liquid in the tank to be delivered through the liquid extraction pipe in a required amount.

In the above tank, a cylindrical body is extended downward from the outer periphery of the lower end of the tank so that the tank can stand on the floor or the like.

[0004]

In the conventional tank described above, both the gas supply pipe and the liquid take-out pipe are inserted in the cap. In this case, when the liquid take-out pipe is inserted through the center of the cap, the gas supply pipe largely separates from the center of the cap, and the cap becomes larger than necessary. Therefore, in general, both the gas supply pipe and the liquid take-out pipe are inserted at positions eccentric from the center of the cap.However, in this way, the lower end of the liquid take-out pipe is displaced from the liquid reservoir provided at the center of the bottom surface of the tank. It may happen. For this reason, it is also practiced to bend the liquid take-out pipe in a dogleg shape and rotate the liquid take-out pipe at a predetermined angle so that the lower end of the liquid take-out pipe coincides with the liquid reservoir. However, since the inside of the tank cannot be seen, if the rotation angle of the liquid take-out pipe is incorrect, the lower end of the liquid take-out pipe may be dislocated from the liquid pool, or the liquid take-out pipe may hit the bottom of the tank during insertion. .

Further, in the conventional tank, in order to make the tank self-supporting, a cylindrical body is hung downward from the outer periphery of the lower end of the tank. However, when the tank is filled with liquid, A considerable weight may be applied to the tubular body, and the tubular body may be deformed.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention inserts a pressurizing gas supply pipe and a liquid take-out pipe into a tank main body at a position deviated from the center of an airtight tank main body and takes out the liquid take-out. A liquid pool was provided at a position eccentric from the center of the bottom surface of the tank body so as to coincide with the lower end of the pipe. A cup-shaped support member can be attached to the bottom of the tank body.

[0007]

[Function] After injecting a chemical solution such as a developing solution into the tank main body and sealing it, nitrogen gas or the like is supplied into the tank main body through a gas supply pipe. When a chemical such as a developer is used, the pipe is connected to the liquid take-out pipe via a coupler and the valve is opened.The liquid in the tank body is delivered to the outside via the liquid take-out pipe due to gas pressure. It

[0008]

Embodiments of the present invention will be described below with reference to the accompanying drawings. Here, FIG. 1 is an overall perspective view of a portable storage tank according to the present invention, and FIG. 2 is a plan view of the portable storage tank.
3 is a vertical sectional view of the portable storage tank, and FIG. 4 is an enlarged view of a main part of FIG.

A cylindrical stainless steel airtight tank body 1 of a portable storage tank has an upper surface 1a which is an inclined surface that gently descends toward a peripheral edge, and a chemical solution such as a developing solution is provided at the center of the upper surface 1a. The inlet 2 is formed, and the cap 3 is attached to the outer peripheral portion of the inlet 2 via a double thread.

A plurality of (four) plate-like columns 4 are erected on the outer peripheral portion of the upper surface 1a of the tank body 1, and an annular protect pipe 5 is supported by the upper ends of the columns 4. There is. Here, the strut 4 is provided with an inward constricted portion 4a at an intermediate portion, and a lower surface of the constricted portion 4a is closely adhered to the upper surface 1a of the tank body 1 so as to enhance the attachment strength of the strut 4, In addition, the constricted portion 4a exerts the effect of a spring when it falls and prevents the protect pipe 5 from falling off. Further, the protect pipe 5 has an annular shape having substantially the same diameter as the tank body 1, and a part of the protect pipe 5 has downward curved portions 5a, 5a.

Further, a gas supply pipe 6 for pressurization and a liquid take-out pipe 7 are inserted at a position eccentric from the center of the upper face 1a of the tank body, and the gas supply pipe 6 and the liquid take-out pipe 7 project from the upper face 1a. The pedestals 6a and 7a are attached to the end portions, and the curved portion 5 is attached to the portions near the pedestals 6a and 7a.
By forming a and 5a, the pedestal 6 of the pipe coupler attached via the coupler attached to the pedestals 6a and 7a
It is designed to be easily attached to and detached from a and 7a. The gas supply pipe 6 is short so that its lower end is higher than the liquid level in the tank body 1, and the liquid take-out pipe 7 is long.

On the other hand, the bottom surface 1b of the tank body 1 is inclined toward one side, and a liquid pool portion 1c is formed at the lowest position thereof. The position where the liquid reservoir 1c is formed is directly below the liquid take-out pipe 7, and as a result, the linear liquid take-out pipe 7 is formed.
The lower end of is exposed to the liquid reservoir 1c.

Further, the pedestals 6a and 7a with the cap 3 sandwiched therebetween.
A gas vent valve mechanism 8 is provided at a position opposed to. The valve mechanism 8 has a cylindrical valve case 9 fixed to the upper surface 1a of the tank body 1, and a valve 11 biased in a closing direction by a spring 10 is inserted into the valve case 9 and attached to the upper end of the valve 11. The gas inside the tank body 1 is opened to the atmosphere by pulling the ring 12 upward.

Furthermore, since the bottom of the tank body 1 is inclined as described above, it cannot be self-supporting as it is. Therefore, a cup-shaped support member 13 is fitted on the bottom. On the lower surface of the support member 13, an annular convex portion 13a which is a contact portion with the floor or the like is formed, and a step portion 13b is formed outside the annular convex portion 13a. When the tank main body 1 is vertically stacked on the stepped portion 13b, the protect pipes of the lower tank engage with each other, so that the tanks can be stably stacked and the strength is improved.

[0015]

As described above, according to the present invention,
The gas supply pipe and the liquid extraction pipe, which are inserted into the upper surface of the portable storage tank that stores the chemical liquid such as the developer, are inserted at positions eccentric from the center of the upper surface. It is easy to remove (hose),
The cap will not be made larger than necessary. Also, since the liquid pool formed on the bottom surface of the tank body is also provided at an eccentric position according to the position of the liquid take-out pipe, the lower end of the liquid take-out pipe can be reliably faced to the liquid pool. The liquid inside can be used up to the end without waste. Further, the support member attached to the bottom of the tank is cup-shaped instead of the conventional tubular shape, so that the strength is significantly improved.

[Brief description of drawings]

FIG. 1 is an overall perspective view of a portable storage tank according to the present invention.

FIG. 2 is a plan view of the portable storage tank.

FIG. 3 is a vertical sectional view of the portable storage tank.

FIG. 4 is an enlarged view of a main part of FIG.

[Explanation of symbols]

1 ... Tank body, 2 ... Liquid inlet, 3 ... Cap, 4 ...
Prop, 5 ... Protect pipe, 6 ... Gas supply pipe, 7 ... Liquid take-out pipe, 6a, 7a ... Pedestal, 13 ... Support member, 1
3a ... convex portion, 13b ... step portion.

Front page continued (72) Inventor Yasushi Sengoku 150 Nakamaruko, Nakahara-ku, Kawasaki, Kanagawa Tokyo Ohka Kogyo Co., Ltd. 2-17-11 Minamigaoka, Sakae-cho, Inba-gun

Claims (2)

[Claims] 1. A gas supply pipe for pressurization and a liquid extraction pipe are inserted into an airtight tank body, and the liquid in the tank body is connected to the liquid extraction pipe by the pressure of the gas supplied into the tank body through the gas supply pipe. In a portable storage tank that is designed to be delivered via a liquid injection port is formed at the center of the upper surface of the tank body, and the pressurizing gas supply pipe and the liquid are provided at a position eccentric from the center of the upper surface of the tank body. A portable storage tank, wherein a take-out pipe is inserted, and a lower end of the liquid take-out pipe faces a liquid pool portion provided at a position eccentric from the center of the bottom surface of the tank body. 2. The portable storage tank according to claim 1, wherein a cup-shaped support member is attached to the bottom of the tank body.