US3744450A

US3744450A - Device for reclaiming dry powder particulates

Info

Publication number: US3744450A
Application number: US00200451A
Authority: US
Inventors: S Hardy
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-11-19
Filing date: 1971-11-19
Publication date: 1973-07-10
Anticipated expiration: 1990-07-10

Abstract

A moveable backdrop filter element mounted for travel over a plurality of rollers and arranged for collecting and reclaiming surplus dry powder particulates, such as used in electrostatic deposition systems. A particular feature of the invention is the ready interchangeability of the filter elements to permit the rapid change of deposition colors.

Description

United States Patent 1 Hardy 11 3,744,450 51 July 10,1973

1 1 DEVICE FOR RECLAIMING DRY POWDER PARTICULATES [76] lnventor: Sheila Hardy, 400 North Avenue,

Bartlett, 111. 60103 [22] Filed: Nov. 19, 1971 [21] Appl. No.: 200,451

[52] U.S. C1 118/326, 98/115, 118/309, 118/634 [51] Int. Cl B05b 1/28, BOSb 15/04 [58] Field of Search l18/DIG. 7, 309, 118/326, 634, 639, 640; 117/9341, 102 A; 98/115 SB [56] I References Cited UNITED STATES PATENTS 3,201,272 8/1965 Forshee 117/102 2,752,003 6/1956 Hersey, Jr. et a1 183/61 2,217,247 10/1940 Burns 91/44 3,537,424 11/1970 Sadler 118/6 3,395,972 8/1968 Hardison 23/4 2,730,460 l/l956 Ransburg 117/93 FOREIGN PATENTS OR APPLICATIONS 3,194 9/1910 Great Britain 118/326 X Primary Examiner-Mervin Stein Assistant ExaminerLeo Millstein Attorney-Edward M. Apple [5 7 ABSTRACT A moveable backdrop filter element mounted for travel over a plurality of rollers and arranged for collecting and reclaiming surplus dry powder particulates, such as used in electrostatic deposition systems. A particular feature of the invention is the ready interchangeability of the filter elements to permit the rapid change of deposition colors.

5 Claims, 3 Drawing Figures PATENTEBJUHO'W 3,744,450

h Am H111mmg Fi 1 g 3 33 13 1 5A 13A 25A 24 17 30 3 INVENTOR: 20A 7 L Sheila Hardy BY: 11 (M 2 ATTORNEY DEVICE FOR RECLAIMING DRY POWDER PARTICULATES This invention relates to electrostatic deposition systems, in which dry powder particulates are deposited on work pieces, prior to the heat treating operation.

This invention is an improvement on the invention disclosed in US. letters Pat. No. 3,201,272 issued to me Aug. 17 1965 under my previous name Sheila Forshee. In that Patent 1 disclosed a METHOD AND MEANS FOR TRAPPING AND RECLAIMING POR- CELAIN FRIT. That disclosure concerned itself with the handling of wet substances, whereas the instant disclosure relates to the trapping and reclamation of the over spray of dry powder. used in electrostatic deposition operations.

In the electrostatic deposition and reclamation and other systems, now known to the public, various pieces of equipment are necessitated, for example, in addition to the conventional electrostatic gun and supply elements a cyclone power unit, complicated conduits and bag stations are used and-when the production schedule calls for achange in color, the entire set-up has to be changed, all of which is time consuming and economically unsound, because ofdown-time in production and cost of labor in the change over.

It is therefore an object of this invention to obviate the foregoing difficulties and to produce other beneficial results.

Another object of the invention is to provide a trapping and reclamation system for dry powder particulates,which is compact in size, inexpensive to assemble and operate, and efficient in use.

' Another object of the invention is to provide a dry powder reclamation system,'which is constructed and arranged so that change of colors in the particulates used may be effected rapidly and deconomically.

I Anotherobject of the invention is to provide a mechanism of the character indicated indicated inlwhich the filter media may be changed rapidly by the simple expeident of removal and replacement, through cut out portions of the spray booth housing.

Another object of the invention is to provide an endless b'elt type filtering media, which is carried on rollers, at least one of which is tension adjustable, from the exterior of the device.

Another object of the invention is to provide an endless belt type of filtering media which may be removed,

replaced, and adjusted by removing one or moresimple cover plates from the housing.

Another object of the invention is to provide a mechanism of the character indicated which performs double filtering actions, whereby to render negative emis-- sion-to-atmosphere of particulates, which might be damaging to the ecology. I Another object of the invention is to provide a powder deposition and reclamation system which can readily be used in continuing, or constant indexing, powder coating operations of heavy production.

Another object of the invention is to provide a device of the character indicated in which the filter media for the dry powerder partciualtes may be felt, paper, or any other material which will allow the passage there through of air, but will trap even the finest of particulates to reach the media.

Another object of the invention is to provide a device ofthe character indicated which has a high safety factor in that the collected over shot powder is quickly removed from the spraying area.

Another object of the invention is to provide a device of the character indicated in which'the dry particulates recovered are made more easily accessible for rc-use.

Another object of the invention is to provide means to protect the mediasupport shafts from any powder particulates, which might reach the area between the front and return portions of the endless belt filter.

Another object of the invention is to proivde a mechanism arranged so that air going through the return portion of the endless belt removes any residue of powder, not removed by the brushes, scraper, .or vibrator.

The foregoing and other objects-and advantages of the invention will become more apparent as the description proceeds, reference being made from time to time to the accompanying drawing, forming part of the within disclosure, in which drawing:

FIG. 1, is a side elevational view ofa device embody-' on the line closed the reference character 5, indicates a work' piece,which is being sprayed with a coating from a conventional electrostatic gun. The reference character 7, indicates in general, the spray booth which in this instanceconsists of a comparatively heavy side wall 8, a top wall 9, a back wall 10, an air plenum 10A, and a source of air supply not shown, and a comparatively light weight side wall 11, the major portion 11A, of which is supported, as at 13, and 1 3A at one end of a bridge like, cantilever, assembly 14, comprising

elements

14A, 14B, 14C, and 14D, which assembly is welded, or otherwise secured, as at 15, and 15A, to the heavy side wall 8. The side wall 8 also carries

heavy bearings

16, 17, and 18, which support at one end the rollers 19, and 20, and the shaft of a rotable brush 21 which is used to remove the overspray from the media 25, and cause it to fall into a removalb'e receptacle 258. The brush 21 is rotated by a motor 21A, and belt 218. The rollers 22, and 23 (FIG. 1) are likewise supported at one end by bearings (not shown) carried by the side wall 8. It will be understood that these bearings are large enough, and have thrust capabilities to hold the rollers at one end only, when the bearings at the opposite ends of the rollers are temporarily removed, as hereinafter described. The side wall ll1lA has a cut out portion 24 (FIG. 2) which is substantially of ,the contour of the endless belt filter media 25, which passes over the rollers as shown in FIG. 1. The spaces between the edges of the media belt 25, and the side walls 8-11 are sealed as at25ArThe cut out 24 is trapezoidal in contour and is defined between the adjacent edges of the

portions

11, and 11A of the side wall 11, and is of sufficient width to permit the entry of a mans hands, or any tool, which may be used to'instalL'or remove, the filter media 25, endwise from the rollers. This is an important feature of theinvention as it permits the filters 25 to be removed and replaced from the side of the spray booth, when a change of color is indicated. The filter media may be the material as disclosed in US. Pat. Nos. 2,841,073, 2,875,680, 3,071,060, 3,201,272 issued to me under my previous name,

Sheila Forshee, or it may be cloth, paper, felt or any other material found efficient for use in catching fine, dry powder particulates.

Although I have here in disclosed the use of an endless belt type of filter media, it will be understood that I may also use a media which has ends, and the ends may be joined together by any suitable means to form an endless belt. With such a structure the media could also be positioned over the rollers from the front.

[twill also be understood that I intend to seal the spray booth between the edges of the media 25, and the side walls 8-11 of the of the booth by any suitable means available.

The media 25 is reinforced against air movement in the direction of the arrows, as at 26 and 27 as in conventional practice. The cut out 24 is covered by

removable cover plates

28, 29, and 30 which are secured in place by machine screws 31 (FIG. 1) which engage .30 and the same end of the shaft, of the brush 21 is carried by the side wall 11.

The roller 20 is an idler, as are the rollers 22 and 23.

- g The roller 19 is driven, as at 32, by a belt and motor 33.

The idler 20 is mounted in bearings (not shown) carried by blocks which are adjustable in slides 34, carried on the inside of both the walls 8 and 11A. The blocks are adjusted by threaded rods 35. The rods 35 are accessible through the cut out 24, and a covered cut out (not shown) in the sidewall 8. By adjusting the rods 35, the roller 20 may be moved to and away from the filter media 25. Movement of the roller 20 away from the return section of the filter media 25, developes slack in the endless belt 25, so that it can more easily be removed from the ends of the rollers, through the cut out 24.

In order to protect the rollers from collecting different colored powder, I may insert sleeves 36, (FIG. 3) over the ends of the rollers, which sleeves 36 may also be removed endwise through the cut out 24.

ln order to install or remove the endless belt media 25, the

cover plates

28, 29, and 30 are firt removed. It will be remembered that the

end bearings

19A, 20A, 22A, and 23A are carried by the

cover plates

28, 29,

replacing the

cover plates

28, 29, 30 the bearings 19A,

A, 22A, and 23A carried by them are first placed over the ends of the roller shafts and the cover plates are then secured by the-machine screws 31.

It is believed that the operationof the device is obvi-.

ous from the foregoing description.

Having described my invention, what I claim and de- 1 me to secure by Letters Patent is:

lates from an electrostatic gun, said front wall length of media having a rearwardly directed angular portion arranged to travel over a removable collecting receptacle, means to remove the particulates from said media and deposite them in said receptacle and means to move said media through said front and rear wall areas and return, said rear wall portion of said media being angularly directed with respect to said front wall portion, said media being supported for travel over a plurality of elongated rollers and is removable from said rollers laterally with respect to the length of said media and axially with respect to said rollers.

2. The structure of claim 1, in which said spray booth is provided with at least one trapezoidal shaped side wall opening, which provides access to said mediaand said rollers, said opening having removable covers thereon.

3. The structure of claim 2, in which. at least one of said removable covers supports a bearing having received therein one end of one of said rollers.

4. The structure of claim 1, in which at least one of said rollers is provided with a replaceable protective element.

5. The structure of claim 1, including means to move air through both front and rear wall areas of said media.

* It I! 4R

Claims

1. In a device for trapping and reclaiming dry powder particulates, including a spray booth having an air plenum and an exhaust stack, the improvement consisting of a continuous length of air permeable media, of sufficient tensile strength to prevent shear, forming both a flexible front wall and a flexible rear wall within said booth, said media being positioned ahead of said plenum and stack and arranged to receive powdered particulates from an electrostatic gun, said front wall length of media having a rearwardly directed angular portion arranged to travel over a removable collecting receptacle, means to remove the particulates from said media and deposit them in said receptacle and means to move said media through said front and rear wall areas and return, said rear wall portion of said media being angularly directed with respect to said front wall portion, said media being supported for travel over a plurality of elongated rollers and is removable from said rollers laterally with respect to the length of said media and axially with respect to said rollers.

2. The structure of claim 1, in which said spray booth is provided with at least one trapezoidal shaped side wall opening, which provides access to said media and said rollers, said opening having removable Covers thereon.

3. The structure of claim 2, in which at least one of said removable covers supports a bearing having received therein one end of one of said rollers.