JP3734901B2 - Bellows pump for cleaning - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a bellows pump used mainly for cleaning electronic components such as semiconductors.
[0002]
[Prior art]
Conventionally, pure water has been used for cleaning electronic components such as semiconductors, but it has become clear that this can be efficiently cleaned by spraying it at a high pressure of 50 to 300 kg / cm ² , and the use of a plunger pump Was considered.
[0003]
However, in the plunger pump, there is a possibility that fine metal powder generated by sliding between the metal of the plunger and the cylinder is mixed in the cleaning liquid and adheres to the electronic component, thereby making it a defective product.
[0004]
[Problems to be solved by the invention]
Therefore, it was attempted to use a bellows pump that does not have a sliding part like a plunger pump and does not generate metal powder even if it is torn. It is necessary to improve the durability by reducing the force acting on the bellows by filling oil between the body and balancing the pressure. However, in this case, there is a problem that if the bellows is torn, oil is mixed into the cleaning liquid and the object to be cleaned becomes defective.
[0005]
[Means, actions and effects for solving the problems]
In the present invention, as a means for solving the above problems, since the space between the bellows and the cylinder surrounding the bellows is filled with substantially the same liquid as the cleaning liquid, the cleaning liquid becomes soiled even if the bellows breaks. There is no risk of making the washed product defective.
[0006]
The breakage of the bellows can be detected immediately by the pressure drop of the cleaning liquid.
[0007]
In this specification, the liquid substantially the same as the cleaning liquid is the same liquid as the cleaning liquid, and the main constituent is the same and the mixing ratio of impurities such as dust is sufficient to maintain the cleaning performance. For example, when the cleaning liquid is ultrapure water having a resistance value of 18 megohm centimeters or more, pure water having a resistance value of 1 megohm centimeters or more is referred to as substantially the same liquid.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.
[0009]
In FIG. 1, reference numeral 1 denotes a cylindrical body forming a main body, and a piston 2 having a discharge hole 3 formed in the center thereof is closely and freely slidably fitted into a seal body 4 fitted to the upper part thereof.
[0010]
A bottom member 5 having a suction hole 9 formed in the center thereof is closely fitted and fixed to the lower part of the cylindrical body 1, and a check made up of a spherical valve body 7 and a valve seat 8 is provided in the middle of the suction hole 9. A valve 6 is configured.
[0011]
Attachment cylinders 10 and 11 are fixed to the lower end of the piston 2 and the upper end of the bottom member 5, and a bellows 12 made of synthetic rubber is tightly screwed to the attachment cylinders 10 and 11, respectively.
[0012]
Between the cylinder 1 and the piston 2 and the bellows 12, the same liquid a as the cleaning liquid, for example, pure water is filled when the cleaning liquid is pure water, and the same solvent is filled when the cleaning liquid is a solvent. Yes.
[0013]
In the present embodiment, when the piston 2 rises from the state shown in FIG. 1, a check valve (not shown) provided above the piston 2 is closed and the internal volume of the bellows 12 is increased. Is opened and the cleaning liquid is sucked from a tank (not shown) through the suction hole 9, and then the internal volume of the bellows 12 is reduced when the piston 2 is lowered to the position shown in the figure. Therefore, the lower check valve is closed and the upper check valve is closed. The valve is opened, and the cleaning liquid in the bellows 12 is discharged from the discharge hole 3 and sprayed onto the object to be cleaned, but the same liquid a as the cleaning liquid is filled between the cylinder 1, the piston 2 and the bellows 12. Therefore, even if the bellows is damaged due to long-term use, it is the same liquid that enters the bellows 12 and the object to be cleaned does not become a defective product. Insufficient article cleaned because is immediately detected by a drop in the discharge pressure will not be a large amount of generated.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an embodiment of the present invention.
[Explanation of symbols]
1: cylinder 2: piston 3: discharge hole 6: check valve 9: suction port a: liquid

Claims (1)

When the bellows expands and contracts in the cylinder by the reciprocating motion of the piston, and the internal volume increases due to the extension of the bellows, the check valve provided in the suction hole opens and the cleaning liquid is sucked into the bellows. In the bellows pump for cleaning, in which the check valve closes and the cleaning liquid in the bellows is discharged from the discharge hole to clean the article when the internal volume decreases due to contraction of the bellows. A cleaning bellows pump in which the space is filled with substantially the same liquid as the cleaning liquid.

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