Paint spray booth

Abstract

A paint booth or paint booth system is presented having an upper and lower portion containing a flood plane panel located at the lower portion of the paint spray booth. An annular region is formed within the flood plane panel for receipt of a metal mesh filter removably fixed within the annular region and at least partially above the flood plane panel, for filtering of paint spray booth contents. The paint spray booth may also contain a perforated plate fixed over the filter for regulating the flow of air and bulk fluid through the filter.

Claims

1. A paint spray booth having an upper and lower portion comprising: a flood plane panel located at the lower portion of the paint spray booth; an annular region formed within said flood plane panel; and a metal mesh filter removably fixed within said annular region and at least partially above said flood plane panel, for filtering of paint spray booth contents.

2. The paint spray booth of claim 1 further comprising: a perforated plate fixed over said filter for regulating the flow of air and water through said filter.

3. The paint spray booth of claim 2 wherein said perforated plate is bolted to said flood plane panel in a sealed relationship thereto.

4. A paint spray booth having an upper and lower portion comprising: a flood plane panel located at the lower portion of the paint spray booth; an annular region formed within said flood plane panel, the annular region having an inner peripheral wall; and a metal mesh filter having an outer periphery, said metal mesh filter removably fixed within the inner peripheral wall of said annular region, said metal mesh filter extending above said flood plane panel for filtering of paint spray booth bulk fluid.

5. The paint spray booth of claim 4 wherein said metal mesh filter extends from three to six inches above said flood plane panel.

6. The paint spray booth of claim 4 wherein said inner peripheral wall has a protrusion or tongue, and said metal mesh filter has a groove extending about its outer periphery, said inner peripheral wall and said metal mesh filter fixed in a tongue and groove relationship.

7. The paint spray booth of claim 1 wherein said metal mesh filter is sealed within said annular region.

8. The paint spray booth of claim 4 further comprising a seal between said inner annular peripheral wall and said outer wall.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) FIG. 1 exemplifies a paint spray booth in accordance with the present invention.

(2) FIG. 2 exemplifies the filter and the associated annular region of the flood plane panel in an exploded view.

(3) FIG. 3 is an exploded view that exemplifies the filter and the associated annular region of the flood plane panel, and a perforated cover and an associated seal for sealing of the filter when installed within the annular region of the flood plane panel.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

(4) A paint spray booth is constructed as known in the art. For example only, and not by way of limitation, a paint spray booth may be constructed as described in U.S. Pat. Nos. 6,093,250 and 6,024,796, each herein incorporated by reference. As such, typical operation of any paint spray booth is contemplated. However, in accordance with the present invention, the treatment of the overspray is mechanically modified to result in a reduction in energy, maintenance, equipment, manufacturing, and/or related paint shop costs.

(5) In accordance with the present invention, it has been discovered that effective treatment of the paint overspray can be accomplished by modifying known paint spray booths to incorporate relatively low pressure mixing and treatment of the bulk fluid and the paint overspray, respectively, rather than the relatively high pressure mixing attendant to the vortex chamber as illustrated in U.S. Pat. Nos. 6,024,796 and 6,093,250. Accordingly, a paint spray booth constructed in accordance with the present invention will incorporate a metal mesh filter, woven or sintered for example, and positioned in a plane residing above at least a portion of an adjacent flood sheet or flood plane panel, in lieu of the vortex chamber or acceleration cone incorporated in U.S. Pat. No. 6,024,796, for example. Other metal matrix filters are also contemplated wherein the preferred metal is of the stainless steel variety.

(6) In further accordance with the present invention, a method of treating paint overspray is provided, the method including the following steps: providing a bulk fluid for treating the paint overspray; providing a filter removably positioned within the floor of a flood plane sheet or panel; and directing at least a portion of the paint overspray and bulk fluid through the filter and into a reservoir positioned beneath the paint spray booth.

(7) A method of constructing or retrofitting a paint spray booth is also provided wherein the method includes the following steps: providing a paint spray booth containing one or more flood sheets or flood plane panels; cutting one or more portions of the one or more flood plane panels, each portion consisting of a predetermined area, and each portion corresponding to an open area created by the removal of the portion; installing a wire mesh or metallic mesh filter, or an equivalent thereof, into each open area; and sealing the interface between each filter and each open area, wherein the seal may be a rubber gasket for example. The seal may in fact be fixed to the periphery of the upper or bottom portion of the filter, whereby when the filter is removed, so is the seal.

(8) Accordingly, as shown in FIG. 1, one or more walls 11, and typically a plurality of walls, define a paint spray booth 10 or a containment area for painting an article such as a vehicle. A flood plane sheet or flood plane panel 18 is proximate to, adjoined to, or included within the one or more walls of the paint spray booth 10, and provides an area where bulk fluid is drained from the paint spray booth 10, or, wherein bulk fluid communicates therewith. A filter 14 having a top portion 15 and a bottom portion 17 is removably positioned at least partially above and within an annular or open portion 36 of the flood sheet or flood plane panel 18, and provides a relatively large area for filtration of the bulk fluid as it drains from the paint spray booth 10. The filter 14 may, for example, be assembled by a tongue and groove relationship formed between the filter (grooved side edges) and the flood plane panel 18 (the flood plane edges inherently comprising tongued edges).

(9) As shown in FIG. 2, a first peripheral edge 28 of the filter 14 may have a groove 30 formed about at least a portion of the first peripheral edge 28 of the filter 14. An inner annular wall 32 formed about the inner periphery 34 of the annulus 36 in the flood sheet 18 may contain a corresponding tongue or protrusion 38 extending radially inward and formed at least partially about the inner annular wall. As the filter groove 30 is mated with the flood plane protrusion 38, the filter 14 is thereby installed above the floor of the flood plane in a tongue and groove relationship with the inner peripheral wall 34 of the annulus 36.

(10) In one embodiment, the filter 14 may for example extend completely above the flood sheet 18, and preferably from three to six inches above the surface of the flood plane panel 18, and even more preferably from about five and a half inches above the flood plane panel 18. The filter 14 is thereby assured to be immersed within the flood plane as the level of the bulk fluid rises over the flood sheets 18. It has been found that filtration through the filter 14 is more efficient when the filter 14 is elevated above the flood sheet 18, and it is believed that the residence time of the bulk fluid/paint mixture is slightly increased over the flood plane panels 18, thereby providing a more sedentary flow through the filter 14.

(11) When assembled, the filter 14 thereby fits within an annular or rectangular opening 36 in the flood plane panel 18. The filter 14 may be made from a fine mesh, and preferably a metallic mesh. The bulk fluid passes through the filter 14 into a lower region or reservoir 48 beneath the paint spray booth 10 for recirculation back through an associated system, such as a bulk fluid reservoir. If desired, one or more splash panels 42 angularly or orthogonally extend from an area of the paint spray booth 10 that is adjacent to the bottom portion 17 of the filter 14, into the lower region of the paint spray booth 10. As the bulk fluid passes through the filter 14, the splash panel(s) directs the flow of bulk fluid into lower reservoir beneath the paint spray booth 10 for recirculation back into the system.

(12) In yet another aspect of the invention, a perforated enclosure or panel 42 may be bolted or otherwise fixed over the filter 14, thereby providing a greater retention time within the flood plane area while yet protecting the filter 14 from any copious blocking due to paint solids for example. The perforations 43 of the panel 42 may be iteratively varied depending on what air velocity is desired in the paint booth 10. Furthermore, the perforated panel 42 may be formed with a seal or flange 44 about its outer periphery 46 whereby when the perforated panel 42 is bolted or otherwise fixed to the flood plane panel 18, the perforated panel 42 forms a sealed relationship with the flood plane panel 18.

(13) The filter mesh or the degree of filtration may be varied as determined by local design criteria. Accordingly, the total surface area and the total interstitial area defined by the filter type may be determined on an iterative basis by measuring the pressure drop across the filter and optimizing the filtration mesh based on design requirement.

(14) It will be appreciated that the filter 14 may be readily cleaned or replaced as necessary to maintain the bulk fluid and air flow within system design tolerances. The filter 14 may, for example, be assembled by a tongue and groove relationship formed between the filter 14 (wherein the filter has grooved side edges) and the flood plane panel 18 (wherein the flood plane panel edges inherently comprise tongued edges for mating with the grooved side edges of the filter). When the filter 14 reaches capacity, the filter 14 may be slid from its berth on the edges of the flood plane panel open area 36, and a clean one may be immediately installed, thereby reducing the time needed to maintain the paint spray booth 10. Alternatively, the filter 14 may simply be inverted to expose a cleaner surface from the bottom 17 of the filter 10, whereby the former upper surface 15 now becomes the bottom surface 17 for cleaning thereof. The filter 14 may be supplied by a myriad of suppliers who provide metallic weave filters in pleated or non-pleated form. One such company includes Metal Filters, Inc. from Lorain, Ohio 44053, for example.

(15) Furthermore, one of ordinary skill in the art will also appreciate that the high pressure typically found in venturi systems, for example, is not necessary for optimum paint overspray/bulk fluid contact, particularly in view of the relatively large aggregated surface area of the filter and the resultant overspray/bulk fluid contact. Other structures typically associated with paint spray booths may be utilized in conjunction with the filter/flood sheet assembly to include mist eliminators and baffle system, for example. U.S. Pat. No. 4,704,952 exemplifies the use of such structures and is incorporated herein by reference. In essence, the use of the filter combined with other known paint spray booth structure results in the elimination of mist and emissions flowing out of associated ventilation or paint stacks.

(16) In accordance with the present invention, and again referring to FIG. 1, a paint spray booth 10 is exemplified, but not thereby limited. One or more walls 11 define the containment area 10 for containment of the painting operation. A paint spray booth 10 may be employed to paint an article such as an automobile while moving along a conveyor line passing through the working area of the booth 10. Air 26 is typically moved or directed from an area 12 above the article downwardly around the article for discharge into and through a filter 14 positioned along a center line of the booth 10, for example. Other configurations may be utilized wherein more than one filter 14 is assembled within the flood plane panel and employed within the booth 10. Accordingly, another configuration (not shown) within an automotive paint spray booth 10 might, for example, include a pair of filters existing in a plane coplanar or substantially parallel to the flood sheet or flood plane panel, herein each filter 14 is located beneath each respective rocker panel. As such, at least one filter 14 may be employed in a paint spray booth 10 of the present invention. In any design, bulk fluid 16 is supplied to a pan or flood plane or flood plane panel(s) 18 positioned beneath the articles or vehicle whereby the bulk fluid 16 cascades downward through the filter(s) 14, in fluid communication therewith. Concurrently, therewith, paint overspray 20 may be directly carried onto the pan(s) 18 by forced air 26 and then through filter 14 for contact and for mixing of the paint overspray with bulk fluid 16. Alternatively, or at the same time, paint overspray 20 may also be entrained within bulk fluid 16 in a known manner (exemplified by a fluidized curtain 15) and then supplied to flood sheets or pan(s) 18 whereby the bulk fluid 16 is then drained through filter(s) 14.

(17) One or more benefits may be associated with the present invention, depending on the specific application. For example, it has been found that chemical stability of the bulk fluid with an increased amount of solids is enhanced. Further, other benefits include: reduced energy costs due to a reduction in pressure across the filter as compared to venturi systems; reduced filter costs; reduced water loss due to reduced evaporation; reduced maintenance or booth cleaning costs due to more efficient treatment of the paint overspray; and other cost improvements. Accordingly, paint spray booths incorporating the filter 14 of the present invention will typically observe one or more of the benefits stated. The filter 14 may be provided, for example, by N.S. Technologies, Inc. as described in U.S. Pat. No. 6,162,270, herein incorporated by reference.

(18) It will be understood that the foregoing description of the preferred embodiment of the present invention is for illustrated purposes only. As such, the various structural and operational features herein disclosed are susceptible to a number of modifications commensurate with the abilities of one of ordinary skill in the art, none of which departs from the scope of the present invention as described above and as stated in the claims appended hereto.