JPH0815527B2 - HEPA filter - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a filter, and more particularly to a HEPA filter (High Efficiency) configured to remove deposits with a fluid jet.
Particulate Air Filter).

[Conventional technology]

Generally, the HEPA filter is well known as a filter having an extremely high collection performance, and is used in various technical fields for handling fine powder, for example, in the technical fields such as a chemical manufacturing process and a clean room for semiconductor manufacturing.

[Problems to be solved by the invention]

However, while the normal HEPA filter has a high collection performance, its thickness is considerably large, so it is difficult to clean up after collection, and it must be thrown away. In particular, when the HEPA filter is used in a place where the dust concentration is high, its lifetime is shortened, which is unsuitable for use.

Therefore, in the process of collecting fine metal powder, sulfur powder, toner for copying machines, wheat flour, etc. with the HEPA filter, the dust adhering to the HEPA filter is wiped off from the dust collecting surface. A filter with a clean-up mechanism has been proposed that ejects high-pressure gas from the back side of the surface to remove deposits.

However, in such a filter, the injection of high-pressure gas opens the fibers of the fiber in the portion of the filter element that directly collides with the jet flow of high-pressure gas,
The present inventor has found that there is a problem that dust leaks from that portion.

It is an object of the present invention to provide a filter capable of removing dust from a filter by jetting a fluid jet without damaging the filter element.

[Means for solving problems]

The HEPA filter of the present invention is provided with the protection means at the portion on the back surface side of the dust collecting surface of the filter element, which the fluid jet directly collides with.

[Action]

According to the above-mentioned means, the fluid jet does not directly collide with the filter element, but first directly collides with the protection means, so that the filter element is prevented from being broken by the jet of the fluid jet, and the desired clean Up can be efficiently realized.

[Embodiment 1] FIG. 1 is an enlarged partial explanatory view of an essential part of an embodiment of a filter according to the present invention, and FIGS. 2 (a) and 2 (b) are partially cutaway front views and plan views, respectively. FIG. 4 is a partially cutaway plan view of a dust collector to which the filter of the present invention can be attached, FIG. 4 is a partially cutout front view thereof, and FIG. 5 is a partially cutaway side view thereof.

In this embodiment, the filter is configured as HEPA filter F, configured as HEPA filter F, and
Four HEPA filters F are mounted in the filter housing 2 above the dust collector 1.

The dust collector 1 includes a pedestal 3 that supports a filter housing 2 and the like, a hopper 4 that sucks raw materials by a suction means such as a vacuum pump (not shown), a raw material suction port 5 to the hopper 4, and a collected material. Container 6 for accommodating HEPA filter F, filter base 7 for supporting HEPA filter F, filter attachment / detachment device 8 that detachably fixes HEPA filter F, and compressed air is ejected toward HEPA filter F to attach substances. Cleaning unit 9 for removing the noise, the housing door 10, and the pressure gauge 11
And the exhaust port 12 through which the gas collected by the HAPA filter F is discharged.

The HEPA filter F of this embodiment is composed of a filter element 13 having a fold-like structure in which a laminate of glass fiber and a resin film is formed in a fold shape in the up-down direction, and is viewed from the bottom to the top as seen in FIG. 2 (a). The collected substances such as fine powder contained in the passing gas are collected. In order to keep the folds of the filter element 13 of the HEPA filter F in a state of being separated from each other, a plurality of separators having a bent structure of metal plates are used.
The filter 14 is vertically inserted into each space of the filter element 13, and both ends thereof are fixed to a metal filter casing 16 by a fixing agent 15.

Of the filter elements 13 of this HEPA filter F,
At the portion where the jet stream of the high-pressure gas from the cleaning unit 9 directly collides, that is, at the top of the fold-like bent portion in FIG. It has a structure in which protective means) is applied and reinforced by coating or the like.
Since the protective layer 17 is provided, the jet stream of the high-pressure gas injected from the nozzle of the cleaning unit 9 first collides with the protective layer 17 first, and the filter element
Since it impinges on itself 13 only indirectly, the filter element 13 is effectively prevented from being destroyed by the jet stream of high-pressure gas.

Examples of the material that can be used to form the protective layer 17 include resin and rubber. Examples of such resins include acrylic resins, methacrylic resins,
Examples thereof include polyvinyl acetate, EVA (ethylene-vinyl acetate copolymer), polyvinyl alcohol, polyvinyl chloride, polyacrylamide, nylon, cellulose acetate, nitrocellulose, ethyl cellulose and the like. Further, examples of the rubber include polyisoprene, polychloroprene, butyl rubber, silicone rubber, nitrile rubber and the like.

 Next, the operation of this embodiment will be described.

First, the gas containing fine powder to be collected is sucked by the raw material suction port 5 by the suction force of suction means such as a vacuum pump (not shown).
Is sucked into the hopper 4 from above, and is sucked upward from the hopper 4.

Next, the gas reaches the HEPA filter F above the hopper 4, and after passing through the HEPA filter F to collect fine particles and the like in the gas, only the gas in the clean state is discharged from the exhaust port 12 to the dust collector. 1 is discharged to the outside.

The fine powder or the like collected by the HEPA filter F drops from the HEPA filter F by ejecting compressed air from the upper side of the HEPA filter F by the cleaning unit 9, and is collected in the container 6 through the inside of the hopper 4. . Collected substances such as fine powder in the container 6 are appropriately collected outside as necessary.

In the above collecting step, fine powder is efficiently and reliably collected on the dust collecting surface on the lower surface side of the HEPA filter F.
A jet stream of high-pressure gas is jetted from the cleaning unit 9 in order to brush off the collected matter from the dust collecting surface.

At that time, since the protective layer 17 is adhered to the portion of the filter element 13 of the present embodiment that is directly behind the dust collecting surface, that is, the upper surface, the jet stream from the cleaning unit 9 directly collides with the cleaning element 9. The jet stream from the head impinges directly on this protective layer 17 and not on the filter element 13 itself.

Therefore, it is prevented that the weave or the weave of the fibers of the filter element 13 is opened by the jet flow,
It is possible to prevent dust from leaking.

[Embodiment 2] FIG. 6 is an enlarged partial explanatory view showing a main part of another embodiment of the filter according to the present invention.

In this embodiment, as a protection means for protecting the filter element 13 from the jet stream of high pressure gas,
A protective cover 17a having an arc-shaped cross section is arranged by a mounting portion 18 made of a connecting agent or the like above the top of the filter element 13, that is, the portion where the jet flow directly collides.

Also in the case of the present embodiment, the jet flow of the high-pressure gas injected from the cleaning unit 9 at the time of cleaning up the filter element 13 does not directly collide with the filter element 13, but first directly collides with the protective cover 17a. It is possible to prevent the filter element 13 from being broken.

Examples of the structure and material of the protective cover 17a include metal and plastic (ABS, polyvinyl chloride, polyether, polyester, polyethylene, polypropylene, acrylic,
A plate or sheath made of polystyrene, nylon, ceramics, etc., a plastic film, cloth or paper (with eyes closed by impregnating or applying rubber, resin, etc.), a sheet with metal foil, etc. may be considered.

The present invention is not limited to the above-mentioned embodiment, and various other modifications can be made.

For example, as a means for protecting the jet stream for cleaning up, a structure other than that of the above-mentioned embodiment can be used.

In addition to the dust collector, the filter of the present invention can be widely applied to a device for collecting products by crushing or classification.

〔The invention's effect〕

According to the present invention, a filter that is formed in a fold shape and removes deposits by ejecting a fluid jet, and by providing a protection means at a portion of the filter element that directly collides with the fluid jet, the fluid jet is ejected. At times, the jet flow does not directly collide with the filter element, so that it is possible to prevent the filter element from being broken and prevent dust from leaking.

(2). According to the above (1), the filter, particularly the HEPA filter, can be used without clogging even in a place where the dust concentration is high.

(3). According to the above (1), the cleanup operation can be performed by the continuous fluid pulse jet without destroying the filter element.

(4). According to the above (1), the filter element is reinforced, the strength is improved, and the size can be reduced.

(5). With the above (1), energy can be saved.

[Brief description of drawings]

FIG. 1 is an enlarged partial explanatory view of an essential part of an embodiment of a filter according to the present invention, FIGS. 2 (a) and 2 (b) are partially cutaway front views and plan views, respectively, and FIG. A partially cutaway plan view of a dust collector to which a filter can be attached, FIG. 4 is a partially cutaway front view thereof, FIG. 5 is a partially cutaway side view thereof, and FIG. 6 shows another embodiment of the filter according to the present invention. It is an enlarged partial explanatory view showing an important part. 1 ... Dust collector, 2 ... Filter housing, 3 ... Stand, 4 ... Hopper, 5 ... Raw material inlet, 6 ... Container, 7 ... Filter base, 8 ... Filter attaching / detaching tool, 9 ... … Cleaning unit, 10… Housing door, 11… Pressure gauge, 12… Exhaust port, 13… Filter element, 14… Separator, 15… Fixing agent, 16… Filter casing, 17… Protective layer (Protective measures), 17a ... Protective cover, 18 ... Mounting part, F ... HEPA filter.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-60-261522 (JP, A) JP-A-61-57217 (JP, A) Actual opening Sho-58-91417 (JP, U) Actual opening Sho-56- 141726 (JP, U) Actual public Sho 56-22853 (JP, Y2)

Claims (3)

[Claims] 1. A HEPA filter, which is formed in a fold shape and removes deposits by jetting a fluid jet, wherein a protection means is provided on a portion of the filter element on the back side of the dust collecting surface where the fluid jet directly collides. A HEPA filter characterized by 2. The HEPA filter according to claim 1, wherein the protection means is at least a protective layer applied to a fluid jet collision portion of the HEPA filter. 3. The HE according to claim 1, wherein the protection means is a protection cover arranged so as to cover at least the fluid jet collision portion of the HEPA filter.
PA filter.