JP4755467B2 - Fluid pulsation mitigation device - Google Patents

Description

  The present invention relates to a fluid pulsation mitigation device capable of attenuating and mitigating pulsation during feeding of a fluid in a semiconductor manufacturing factory and other factories using various fluids.

  A fluid pulsation mitigation device that forms an air layer and a fluid layer in the container so that pulsation can be mitigated because pulsation occurs in various chemicals, pure water and other processing solutions used in the semiconductor manufacturing process. Is provided (for example, refer to Patent Document 1). Such a device can relieve pulsation by the pressure of the air layer, but the upper surface of the fluid layer moves vigorously, so that the air in the air layer gradually dissolves into the fluid layer and the amount of air decreases. The initial pulsation mitigating effect could not be expected.

Therefore, there is known a pulsation absorbing device in which an elastic film is provided between the air layer and the fluid layer, or a plurality of elastic bodies are levitated on the upper surface of the fluid layer so as to cover the upper surface of the fluid and prevent air from being melted. (For example, refer to Patent Document 2). However, if the elastic film or elastic body as described above is on the upper surface of the fluid layer and moves up and down with pulsation, generation of fine dust cannot be avoided. Such fine particles are undesirable because they have a great adverse effect on products, particularly in the semiconductor manufacturing process.
JP 2004-183730 A (Claim 1, FIG. 4) Japanese Utility Model Publication No. 4-17816 (Utility Model Registration Request (1), Fig. 1)

  The problem to be solved by the present invention is that in a fluid pulsation mitigation device that mitigates fluid pulsation by the action of an air layer, dust is not generated by eliminating moving parts, air penetration is reduced, and initial It is an object of the present invention to provide a fluid pulsation mitigation device that can maintain a pulsation mitigation effect.

  According to the present invention, in the fluid pulsation mitigation device in which an air layer is formed above the container, a fluid layer into which fluid with pulsation flows is formed below, and the pulsation is mitigated by the air layer. A reservoir layer leading to the fluid inlet / outlet and an inner partition located above the reservoir are formed in the container, and a lower end of the inner partition is opened at a lower surface of the inner partition and an air layer element is formed inwardly. A fluid pulsation mitigation device characterized by providing a plurality of cylinders is provided, and the above-mentioned problems are solved.

  Further, according to the present invention, there is provided the fluid pulsation mitigation device in which a wave-dissipating wall is provided in the reservoir so that the fluid flowing in from the inlet contacts, and the wave-dissipating wall is formed between the lower surface of the inner partition and the container. It is provided with a space between the bottom surface.

  The present invention is configured as described above, an internal partition is formed above the reservoir, a plurality of cylinders whose lower ends are open to the lower surface of the internal partition are formed in the internal partition, and an air layer element is formed in the cylinder Therefore, the air layer is composed of a plurality of air layer elements formed dispersed in a plurality of cylinders, and the air layer element in each cylinder has an area in contact with the fluid when a single air layer is formed as in the conventional case. In comparison with this, it is possible to significantly reduce the dissolution rate, and the rate of dissolution of air into the fluid can be reduced. As described above, since the apparatus of the present invention does not have a movable part unlike the conventional apparatus, dust is not generated, and it can be used with peace of mind even in a process in which extremely fine dust is a problem, such as a semiconductor manufacturing process. be able to.

  The fluid with pulsation flowing into the container from the inflow port hits the wave-dissipating wall and enters the reservoir through the gap below the wave-dissipating wall. At this time, the pulsation (wave) that preserves the pressure jumps like a mountain on the inner surface of the wave-dissipating wall and the lower surface of the inner bulkhead, and becomes a complicated pulsation (the pressure at the wave front and the wave tail is different). It flows with a tendency to spread. In the conventional apparatus, since there is one air layer, intense waves are generated on the upper surface of the fluid layer. However, in the present invention, since the fluid hits the lower surface of the internal partition wall, it is dispersed and enters each cylinder. The wave motion on the upper surface of the fluid in the cylinder is gentle, the air is less melted, the wave is surely extinguished by the pressure of each air layer element, and the pulsation is alleviated.

  Further, in the conventional pulsation mitigation device, the container forming the air layer is composed of a single plate member, so that the pressure resistance is poor. However, in the present invention, the air layer element is provided in a plurality of cylinders provided in the internal partition wall. Is formed and the air layer is dispersed, so that it has sufficient pressure resistance and durability against pulsation caused by intense pressure and pressure reduction.

  1 is a front view, FIG. 2 is a longitudinal sectional view of FIG. 1, FIG. 3 is a longitudinal sectional view of FIG. 2, and FIG. 4 is a container in which a bottom plate and a wave-dissipating wall are omitted. FIG. The container (1) of the present invention can be made of an appropriate material corresponding to a fluid to be applied, such as a plastic material or a metal material having chemical resistance, and is formed in a substantially rectangular parallelepiped shape as a whole, and has an inlet (2), The outflow port (3), the drain (4), the exhaust port (5) and the like are provided on the same surface, the front side in the figure. As will be described later, each of these openings can be provided at an appropriate position so that the fluid entering from the inlet (2) flows out from the outlet (3) after receiving the pulsation mitigating action. The inflow port (2) and the outflow port (3) are provided apart on both ends of the front.

  The said container (1) has the storage layer (6) connected to the said inflow port (2) and the outflow port (3) below, and the lower surface is sealed by the bottom plate (7). An internal partition (8) is formed above the reservoir (6), and a bolt (9) for reinforcing the bottom plate (7) in a fixed state is provided between the bottom plate (7) and the internal partition (8). ing. The drain (4) is also in communication with the reservoir (6).

  The reservoir (6) is provided with a wave-dissipating wall (10) so that the fluid entering from the inlet (2) contacts. The wave-dissipating wall (10) is formed in a substantially L-shaped cross section, the tip of the horizontal portion (11) is fixed to the inner surface of the container (1) by welding or the like, and the lower end of the standing portion (12) and the bottom plate (7 ) Is formed with a lower gap (13) through which the fluid passes. An upper gap (15) is formed between the horizontal portion (11) and the lower surface (14) of the internal partition wall (8).

  A plurality of cylinders (16) are formed in the inner partition wall (8) so that the lower end is opened at the lower surface (14), and an air layer element (17) is provided in the cylinder (16). ing. The inner partition wall (8) is preferably formed integrally with the container (1) so as to be obtained easily and economically, and a plurality of cylinders (16) are formed by drilling from the lower surface side. It may be made separately from (1) and inserted into the container and fixed. In the case of making a separate body, a plurality of holes may be formed in one block body to provide a cylinder, or a plurality of independent cylindrical cylinders may be combined to form an internal partition (not shown).

  The cylinder (16) is formed in a circular cross section as shown in FIG. 4, but may be formed in a polygonal cross section. The exhaust port (5) communicates with the cylinder (16).

When a fluid with pulsation flows in from the inlet (2), the fluid hits the wave-dissipating wall (10), passes through the lower gap (13), passes through the inside of the wave-dissipating wall (10), and rises. And enters the upper gap (15). When the air enters the cylinders (16) through the lower surface (14) of the internal partition wall (8), the air in the cylinders stays upward to form an air layer element (17). It enters to a height that balances the pressure of the air layer element (17), the pulsation is mitigated by the pressure action of the air layer element (17), and flows out from the outlet (3) provided at a position away from the inlet. To do. Thereafter, the fluid entering from the inlet also rises in the reservoir and enters the cylinder, so it is mixed with the fluid in the cylinder, pulsation is relaxed, and flows out from the outlet.

  The air layer elements (17) are independent from each other, and have a smaller contact area with the fluid and less pulsation of the fluid entering the cylinder as compared with the case where one conventional air layer is provided. As a result, the movement of the upper surface of the fluid in the cylinder can be moderated, the dissolution rate of air dissolved in the fluid can be reduced, and the initial pulsation mitigating effect can be maintained for a long period of time.

The front view which shows one Example of this invention. The longitudinal cross-sectional view of FIG. The longitudinal cross-sectional view of FIG. The bottom view of the container which excluded the baseplate and the wave-dissipating wall.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Container 2 Inlet 3 Outlet 6 Reservoir 7 Reservoir 7 Bottom plate 8 Internal partition 10 Dissipating wall 13 Lower gap 15 Upper gap 16 Cylinder 17 Air layer element

Claims (1)

  Forming a reservoir below the container and sealing the bottom with a bottom plate; providing an inlet and an outlet communicating with the reservoir on both sides of the container; forming an internal partition above the reservoir; A fluid pulsation mitigation device in which a plurality of cylinders, each having a lower end opened at the lower surface of the internal partition wall, are provided in the internal partition wall.

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