Abstract:
A blasting cabinet for use in cleaning a work piece with abrasive intrained in an air stream under pressure. An enclosure having multiple access openings and configured interior surfaces that direct spent abrasive forward to a collection area in spaced relation to the supported work piece on a solid work surface within said cabinet.

Description:
BACKGROUND OF THE INVENTION 
     1. Technical Field 
     This invention relates to blasting cabinets that are used to conduct high pressure abrasive cleaning of articles positioned within. 
     2. Description of Prior Art 
     Prior art devices of this type have been used in industry for many years. Typically bench mounted or free standing cabinets (so called a blast cabinet) are used in which an abrasive material such as sand is propelled at high velocity by a compressed gas stream such as air directed against a surface of a work piece by a blast gun, all within the confines of the cabinet. 
     Examples of such blasting cabinets typically have a viewing window and a pair of sealed access gloves that allow the user to manipulate the blasting gun and article within the cabinet while being safely outside. Typically, cabinets have a collection area positioned directly below the work piece which is placed on a screen support that extends over the collection opening. The collection area on prior art blasting cabinets are funnel shaped so as the used abrasive collects within it can be picked up and reused by the gun utilizing a pick-up tube and venturia effect. In some applications a vacuum system is connected to the cabinet collecting dust and light debris particles from within the cabinet&#39;s atmosphere to a collection filter bag within the vacuum. Back-up air enters the cabinet via an air inlet which is shielded from abrasive within the cabinet; see for example U.S. Pat. Nos. 3,300,902, 5,601,480, 5,971,837 and 4,918,873. 
     In U.S. Pat. No. 3,300,902 a dry abrasive honing device is disclosed wherein a blasting cabinet is shown having a cyclone separator within. 
     U.S. Pat. No. 5,601,480 is directed to a cleaning machine that uses liquid mixture with granules that are circulated over the article within the cabinet to be cleaned. 
     U.S. Pat. No. 5,971,837 discloses a barrel-shaped abrasive blasting cabinet having a collection and storage hopper for the collection and feeding of blasting gun. 
     Finally, U.S. Pat. No. 4,918,873 illustrates an apparatus for refinishing golf clubs with an enclosure having access rubber gloves mounted in the openings in the front wall and a golf club flexible access slit in one of the sidewalls so that the club head can be positioned within the closure for cleaning. 
     SUMMARY OF THE INVENTION 
     A blasting cabinet having an interior configuration and collection hopper that enhances the circulation and effectiveness of abrasive material intraned in a high velocity air stream directed at a work piece to be cleaned. By reconfiguring and repositioning the abrasive supply and collection hopper and supporting the work piece on an integral solid surface, the unique air abrasive circulation pattern is achieved that produces a self-cleaning and collection abrasive action. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the blasting cabinet of the invention; 
     FIG. 2 it a side elevational view of the cabinet of the invention; 
     FIG. 3 is a cross-sectional view on lines  3 — 3  of FIG. 1; 
     FIG. 4 is a top, plan view of the invention with portions cut away for illustrating air flow patterns graphically within during use; 
     FIG. 5 is a top plan view of the invention with portions cut away for illustrating alternate air flow patterns graphically within during use; and 
     FIG. 6 is a front elevational view. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIGS. 1 and 2 of the drawings, a blasting cabinet  10  of the invention can be seen having a top  11 , a bottom  12  and front and back walls  13  and  14  respectively. Integral sidewalls  15  and  16  complete the cabinet enclosure with an access door  17  in the sidewall  16 . The door  17  is secured to the back wall  14  by a hinge  17 A and held in selective closed position by a door latch  17 B. 
     The front wall  13  has a vertical portion  13 A with a pair of openings  18  and  19  for the insertion of hands within protective flexible glove inserts  18 A and  19 A respectively secured to and extending from within the openings as hereinbefore described. An angle portion  13 B of the front wall  13  has a viewing window  20  within as is well known and understood within the art. 
     A collection and supply funnel  21  extends from the bottom  12  defining an opening therein along the base of the vertical front wall portion  13 A as best seen in FIG. 3 of the drawings. A screen  22  extends over an opening defined by the funnel forming an abrasive collection area. 
     The funnel  21  has parallel front and back panels  21 A and  21 B with interconnecting angularly inclined oppositely disposed side panels  22 A and  22 B. An extension tube  23  and incline gate valve  24  communicates with and extends from an outlet opening  25  within a base member  26  of the funnel that interconnects said respective panels  21 A,  21 B and  22 A and  22 B as best seen in FIG. 1 of the drawings. 
     A pick-up tube  27  is secured within the funnel  21  having an inlet opening  27 A at one end and an oppositely disposed outlet engagement fitting  27 B. 
     A vacuum hose attachment inlet fitting  28  extends through the sidewall  15  providing a selective access opening for the use of dust removal and vacuum system (not shown) as will be well understood by those skilled in the art. An air make-up inlet assembly  29  is positioned on the upper portion of the back wall  14  having an aperture at  30  within a rectangular baffle configuration  31  positioned thereover on the inside wall surface at  32 . 
     In use, a power abrasive blast gun  33  is positioned within the cabinet  10  through the access door  17 . The gun  33  is connected to the pick-up tube outlet  27 B via an abrasive supply hose  34  and to a high pressure air source (not shown) by an air supply hose  35  that extends from within the base cabinet  10  of the invention through a hose inlet fitting  36  in the back wall  14  as best seen in FIGS. 2 and 3 of the drawings. 
     The power gun  33  which is typical within the art is supplied air under pressure creating a venturia effect drawing up abrasive material from within the supply and collection funnel  21  and dispensing it at high velocity through a nozzle  33 A against a work piece W to be cleaned. It will be evident from the above description that the work piece W is positioned inside the blast cabinet and on a unique solid support surface  37  defined by the bottom  12  of the cabinet. 
     Referring now to FIGS. 3-5 of the drawings, a unique abrasive flow pattern can be seen as illustrated by directional flow arrows A. In FIG. 3 of the drawings, the abrasive flow pattern is illustrated in side elevational view wherein the abrasive strikes the work piece W and deflects around within the contoured cabinet interior of the invention due to the solid work surface  37  and its relationship to the back and side surfaces  14 ,  15 , and  16  respectively and the intervening top and front walls  11 ,  13 A and  13 B respectively. The abrasive material as indicated by the directional flow arrows A flows around within the interior forward to the funnel opening along the base of the front wall  13 A. 
     Referring now to FIGS. 4 and 5 of the drawings, an illustrated top plan view of the cabinet is seen showing the abrasive flow pattern arrows A from the blast gun  33  with the work piece positioned in alternate positions as would be found in a typical application use. 
     It will be seen that the abrasive flow patterns indicated by the abrasive flow arrows A within the high velocity air stream around within the cabinet interior surface and forward to the opening of the collection and supply funnel  21  provides a unique self-cleaning and recycling environment. 
     It will be apparent from the above description that a more efficient abrasive cleaning action is achieved within the blast cabinet  10  of the invention by providing the solid support surface  37  for the work piece so as to enhance the circulation within the cabinet. By having the abrasive recess opening of the collection and supply funnel  21  along the inside base of the front vertical wall portion  13 A, the spent abrasive is circulated about the interior of the cabinet working its way forward to the front of the cabinet and into the collection supply funnel  21  via the cover screen  22 . 
     It will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention.