JP2006132474A - Ejector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ejector capable of alleviating installation conditions inside a clean room. <P>SOLUTION: The ejector generating negative pressure by discharging pressurized air from a nozzle 7 to a diffuser 8 is provided an exhaust gas cleaner 21 using a hollow fiber membrane as a filter 23. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an ejector that generates a negative pressure based on supply of a compressed fluid, and more particularly to an ejector used in a clean room.

The ejector generates negative pressure in the intake port by discharging the compressed fluid supplied to the supply port from the exhaust port together with the outside air sucked from the intake port.
The above ejectors are disclosed in Patent Document 1 and Patent Document 2.
JP 2003-194000 A JP 2003-35300 A

  When the ejector as described above is used in a clean room, the exhaust discharged from the exhaust port cannot be discharged into the clean room. Therefore, it is necessary to discharge outside the clean room through a pipe.

  Accordingly, there is a problem that a space for installing the piping is required and the opening direction of the exhaust port for connecting the piping is restricted, so that the installation work of the ejector becomes complicated.

  An object of the present invention is to provide an ejector capable of relaxing installation conditions in a clean room.

  The above object is achieved by an ejector including an exhaust cleaner using a hollow fiber membrane as a filter medium.

  ADVANTAGE OF THE INVENTION According to this invention, the ejector which can ease the installation conditions in a clean room can be provided.

  Hereinafter, an embodiment of an ejector embodying the present invention will be described with reference to the drawings. In the ejector shown in FIG. 1, a cover 2 is attached to the upper surface of a body 1, and a pressure port 3 is provided on the cover 2.

  An electromagnetic valve 4 is attached to the upper surface of the cover 2, and the supply of pressurized air to the pressurizing port 3 is controlled by the electromagnetic valve 4. A supply port 5 to which pressurized air is supplied and an intake port 6 are respectively provided on the side surfaces of the body 1. Pressurized air supplied to the supply port 5 is supplied to the solenoid valve 4 through a communication hole (not shown) provided in the cover 2, and is supplied to the pressurization port 3 based on the opening / closing operation of the solenoid valve 4. Supplied.

The intake port 6 is connected to a suction conveyance device or the like via another pneumatic device such as a filter or a regulator.
A nozzle 7 is attached to the upper surface of the body 1 at a position below the pressure port 3, and a space formed below the nozzle 7 communicates with the intake port 6 and opens downward. .

  A first diffuser 8 is disposed below the opening of the nozzle 7, and a second diffuser 9 is disposed below the first diffuser 8. The peripheral edges of the first and second diffusers 8 and 9 are fixed to the body 1 by a cylindrical tube 10 fitted to the lower portion of the body 1.

The first diffuser 8 partitions the space in the body 1 up and down, and the second diffuser 9 partitions the body 1 and the space in the tube 10.
The first diffuser 8 is formed in a substantially conical shape, and a first throat portion 11 is formed at the center thereof. The first throat portion 11 is extended with a constant diameter. When pressurized air is ejected from the nozzle 7 to the first throat portion 11, the air in the space above the first diffuser 8 is caught in the first throat portion 11. By this operation, a negative pressure is generated in the space above the first diffuser 8, and the first vacuum chamber 12 is generated.

  Below the first throat portion 11, a second throat portion 13 that protrudes into the tube 10 is formed in the second diffuser 9. Then, when pressurized air is ejected from the first throat portion 11 to the second throat portion 13, the air in the space above the second diffuser 9 is caught in the second throat portion 13. By this operation, a negative pressure is generated in the space above the second diffuser 9, and the second vacuum chamber 14 is generated.

  A plurality of communication holes 15 for communicating the first and second vacuum chambers 12 and 14 are formed around the first throat portion 11 of the first diffuser 8. Around the periphery, a rubber plate-like check valve 16 that covers the communication hole 15 from the second vacuum chamber 14 side is attached.

  A valve stopper 17 is fitted on the outer periphery of the first throat portion 11 below the check valve 16 to position the check valve 16. With such a configuration, when the atmospheric pressure in the second vacuum chamber 14 becomes lower than the atmospheric pressure in the first vacuum chamber 12, the check valve 16 is opened, and the first and second vacuum chambers 12 and 14 are equal in pressure. It comes to become.

The lower end portion of the second throat portion 13 has its inner diameter gradually enlarged at a predetermined angle in order to efficiently discharge pressurized air.
A bottom cover 18 is fitted to the lower end of the tube 10, and an exhaust port 19 is formed at the center of the bottom cover 18. Then, the air discharged from the second diffuser 9 is discharged from the exhaust port 19. A cylindrical silencer 20 is provided between the tip of the second diffuser 9 and the exhaust port 19.

  A clean room exhaust cleaner 21 is attached to the exhaust port 19. The clean room exhaust cleaner 21 includes a case 22 and a filter medium 23 filled in the case 22.

  In the case 22, a cylindrical accommodating portion 24 having an open front end and a base end portion 25 formed so as to be attachable to the exhaust port 19 are integrally formed, and a communication hole formed in the base end portion 25. 26, the accommodating portion 24 communicates with the exhaust port 19.

  The accommodating portion 24 is filled with a filter medium 23 composed of a polypropylene porous hollow fiber membrane. That is, the filtering material 23 is formed by folding a large number of thread-shaped hollow fiber membranes cut into a predetermined length into two and bundling them, and impregnated with urethane resin on the cut end side, so that the space between the hollow fiber membranes is reduced. A solid portion 27 is formed which is solidified in a sealed state. Then, the solid portion 27 side is fitted into the case 22 with the opening end side of the case 22 being set.

  Since the hollow core portion of each hollow fiber membrane is opened at the opening end of the case 22, the air discharged to the exhaust port 19 passes through each hollow fiber membrane from the outer surface side toward the hollow core portion. Then, the air is discharged from the air core portion to the open end of the case 22. In this way, particles and the like are filtered when air passes through the hollow fiber membrane.

  Next, the operation of the ejector configured as described above will be described. When the solenoid valve 4 is opened while pressurized air is supplied to the pressurized port 3, a high-speed air flow is ejected from the nozzle 7 as the pressurized air.

  The air discharged from the nozzle 7 flows into the first throat part 11, and at this time, the air in the first vacuum chamber 12 is caught in the first throat part 11 by the air flow, and the first vacuum chamber A negative pressure is generated within 12. Then, outside air is sucked from the intake port 6 by the negative pressure.

  Air discharged from the first throat portion 11 flows into the second throat portion 13. Then, the air in the second vacuum chamber 14 is caught in the second throat portion 13, and a negative pressure is generated in the second vacuum chamber 14. When the atmospheric pressure in the second vacuum chamber 14 becomes lower than the atmospheric pressure in the first vacuum chamber 12, the check valve 16 opens and air is drawn from the first vacuum chamber 12 into the second vacuum chamber 14. .

The air flowing into the second throat portion 13 passes through the silencer 20 and is discharged from the clean room exhaust cleaner 21.
By such an operation, a negative pressure is generated in the first vacuum chamber 12 by the first diffuser 8, and the negative pressure is supplied to the intake port 6. Further, air is drawn into the second vacuum chamber 14 from the first vacuum chamber 12 through the check valve 16 by the second diffuser 9, and the intake capacity of the outside air sucked from the intake port 6 is secured.

With the ejector configured as described above, the following operational effects can be obtained.
(1) By supplying pressurized air to the pressurized port 3, negative pressure can be generated in the intake port 6, and outside air can be sucked into the intake port 6.
(2) The exhaust discharged from the exhaust port 19 can be filtered by the clean room exhaust cleaner 21. Therefore, the exhaust can be discharged into the clean room.
(3) Since the exhaust can be discharged into the clean room, there is no need to connect an exhaust pipe to the ejector. Therefore, the freedom degree of the installation position of the ejector in a clean room can be improved.
(4) The exhaust sound can be further silenced by the clean room exhaust cleaner 21.
(5) Since it is only necessary to attach the clean room exhaust cleaner 21 to the exhaust port 19, the configuration can be made extremely simple.
(Second embodiment)
FIG. 2 shows a second embodiment. The configuration of the ejector of this embodiment is substantially the same as that of the first embodiment, and the same components are denoted by the same reference numerals and description thereof is omitted.

  The lower end of the tube 10, that is, the exhaust side end, is filled with the filter medium 28 as a clean room exhaust cleaner without attaching the bottom cover 18 of the first embodiment. The filter medium 28 has the same configuration as that of the first embodiment, and is fitted so that the solid portion 29 is located on the opening end side of the tube 10.

With such a configuration, the exhaust gas from the ejector is filtered by the filter medium 28 and discharged, so that the same effect as that of the first embodiment can be obtained.
(Third embodiment)
FIG. 3 shows a third embodiment. The configuration of the ejector of this embodiment is substantially the same as that of the first embodiment, and the same components are denoted by the same reference numerals and description thereof is omitted.

  One end of a cylindrical cleaner case 30 is attached to the lower end of the tube 10, and the filter case 31 is filled in the cleaner case 30 to constitute a clean room exhaust cleaner. An exhaust hole 32 is opened in the side surface of the cleaner case 30.

A bottom cover 33 is attached to the other end of the cleaner case 30, a drain hole 34 is formed in the bottom cover 33, and a water pipe (not shown) is connected to the drain hole 34.
The filter medium 31 is formed by bundling a large number of linear hollow fiber membranes, impregnated with the urethane resin at both ends thereof to form solid portions 35a and 35b, and an air core is opened at the end of each hollow fiber membrane. ing. And each hollow fiber membrane is comprised with the membrane | film | coat provided with hydrophobicity, and does not permeate | transmit a water | moisture content.

  In the ejector configured as described above, the exhaust discharged from the second diffuser 9 is filtered through the hollow fiber membrane of the filter medium 31 and discharged from the exhaust hole 32. The moisture contained in the exhaust gas passes through the hollow core of each hollow fiber membrane and is discharged from the drain hole 34 without passing through the hollow fiber membrane.

With the ejector configured as described above, it is possible to obtain the same operational effects as those of the first and second ejectors, and to remove moisture contained in the exhaust gas.
You may implement the said embodiment in the following aspects.
-The filter medium may be composed of a porous hollow fiber membrane other than polypropylene.

It is sectional drawing which shows 1st embodiment. It is sectional drawing which shows 2nd embodiment. It is sectional drawing which shows 3rd embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Body 5 Supply port 6 Intake port 7 Nozzle 8,9 Diffuser 10 Tube 19 Exhaust port 21 Exhaust cleaner 23,28,31 Filter material 27 Solid part

Claims (5)

In the ejector that generates negative pressure by discharging pressurized air from the nozzle to the diffuser,
An ejector comprising an exhaust cleaner using a hollow fiber membrane as a filter medium.   The ejector according to claim 1, wherein the exhaust cleaner is filled with the filter medium in a case, and the case is attached to an exhaust port.   2. The ejector according to claim 1, wherein the exhaust cleaner is configured by filling the filter medium at an exhaust side end portion in a tube of the ejector. 3.   The filter medium is formed by folding a large number of thread-like hollow fiber membranes into two, bundling them, hardening the cut end side of the hollow fiber membranes with resin, and allowing exhaust to permeate from the surface of the hollow fiber membranes to the air core. The ejector according to claim 2 or 3, wherein   The filter medium is formed by bundling a large number of thread-like hollow fiber membranes having hydrophobicity in a straight line, both ends of the hollow fiber membranes are solidified with resin, and exhaust gas is transmitted from the air core part of the hollow fiber membranes to the surface. 4. The ejector according to claim 3, wherein moisture in the exhaust gas passes through the air core.

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