SLIDING DRAWER DRY FILTRATION SYSTEM FOR A PAINT BOOTH

[0001] This application claims the benefit of U.S. Provisional Patent Application Ser. No. 63/125,528 filed on Dec. 15, 2020, the entire disclosure of which is incorporated herein by reference.

[0002] The subject disclosure relates in general to the field of paint booths, and more particularly to a dry filtration system for capturing and removing paint particles from a downdraft of process air in a paint booth.

[0003] This section provides background information related to the present invention which is not necessarily prior art.

[0004] Paint booths are used in many industrial applications for applying paint or other coatings to components or assemblies. However, not all of the paint is transferred to the components or assemblies in the painting process, resulting in paint overspray that becomes entrained within a downdraft of process air within the paint booth. These paint particles must be removed and purified from the downdraft of process air before the air can be released into the environment or introduced back into the paint booth for subsequent use as downdraft air.

[0005] In paint booth applications utilizing a large amount of paint consumption, such as paint booths for painting vehicle bodies, it is common to utilize a wet scrubber based filtration system to remove the paint from the downdraft of process air. One such example is disclosed in Applicant's U.S. Pat. No. 11,085,058. However, wet scrubbers are known to require a large amount of energy usage such as is required to circulate the large amounts of water through the paint booth assembly to capture the paint overspray and treat the resultant sludge. The processing of the resultant sludge can also be cost-intensive due to the requisite processing and potential use of chemicals to treat and dispose of the paint sludge. Additionally, due to the presence of water in the paint booth, the downdraft air necessarily takes up moisture that must be later processed out of the air before reintroduction into the paint booth, resulting in additional energy consumption.

[0006] Accordingly, in some applications in which the component or assembly is not as large as a vehicle body and thus less paint consumption is required, or where lower volume production requirements are present for the components or assemblies to be painted, it is common to utilize a dry filtration system in lieu of the wet scrubber filtration systems, namely because dry filtration systems have lower energy use requirements relative to their wet scrubber counterparts. In these dry filtration systems, the downdraft of air is passed through a filter module including at least one dry filter before the filtered air is released to the environment or recirculated back into the paint booth. When the dry filter becomes loaded excessively with paint particles, the filter module is taken “off-line” by a paint booth operator and replaced with a new filter module. Two such examples are disclosed in U.S. Pat. No. 10,350,627 and US Patent Application Publication No. 2016/00232321. However, the removal and replacement of the filter modules in these dry filtration systems is a time consuming process, namely because the entire filter module, which is a bulky structure, must be handled, removed and disposed of by the paint booth operator. These prior art dry filtration systems often require complicated rail structures or lifting trucks to remove and replace the bulky filter modules. Once removed, the bulky filter modules can also create disposal issues due to their large size.

[0007] Accordingly, a continuing need exists for a dry filtration system for a paint booth that provides for quicker and easier removal and disposal of the filters from the filter modules.

[0008] This section provides a general summary of the invention and is not intended to be a comprehensive disclosure of its full scope, aspects, objectives, and/or all of its features.

[0009] A paint booth assembly according to the subject disclosure includes a dry filtration system for filtering paint particles from a downdraft of air. The paint booth assembly includes a paint booth having a pair of side walls, and a grated floor extending between the pair of side walls to separate the paint booth between a spray portion disposed above the grated floor and a paint filtration portion disposed below the grated floor. At least one filter module is disposed in the paint filtration portion for receiving a downdraft of process air including entrained paint particles from the spray portion. The filter module includes a plurality of filter drawers sequentially arranged relative to one another along a flow path of the downdraft of air and each defining a filter compartment housing at least one disposable filter. Each of the filter drawers are slideably connected to the paint booth and slideable relative to one of the side walls between filtering and cleaning positions. In the filtering position, the filter compartment of the respective filter drawer is disposed within the paint filtration portion of the paint booth for filtering paint particles from the downdraft of process air. In the cleaning position, the filter compartment of the respective filter drawer is disposed in an outside environment of the paint booth for allowing the at least one disposable filter to be removed and replaced by a paint booth operator.

[0010] The filter module having a plurality of slideable filter drawers allows the disposable filters to be more easily and quickly replaced relative to the prior art designs which require the removal and replacement of the entire filter module from the paint booth, and thus a more complicated and cumbersome filter replacement process. In contradistinction, the subject dry filtration system including at least one filter module having a plurality of slideable filter drawers allows selective disposable filters to be discretely and individually replaced by a paint booth operator, while leaving the other filter drawers in the filter module “on-line” and in the closed position for continuing to filter the paint particles from the downdraft of process air. Thus, the filter module in accordance with the subject invention reduces the maintenance/labor requirements, and provides a solution which allows for faster disposable filter replacement relative to the prior art designs.

[0024] Example embodiments will now be described more fully with reference to the accompanying drawings. The example embodiments are provided so that this disclosure will be thorough and fully convey the scope to those skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, mechanisms, assemblies, and methods to provide a thorough understanding of various embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms, and that neither should be construed to limit the scope of the disclosure.

[0025] Referring to the drawings, wherein like numerals indicate corresponding parts throughout the several views, a paint booth assembly 20 is generally shown in FIGS. 1-5 and includes a paint booth 22 including a dry filtration system 24 for removing paint particles from a downdraft of air 25 in the paint booth 22. The paint booth 22 includes a pair of side walls 26 that extend from an entry end 28 to an exit end 30 for receiving a vehicle 32, or other component or assembly, to be painted. A conveyor 34 is located centrally between the pair of side walls 26 and extends along a central plane P from the entry end 28 to the exit end 30 to convey the vehicle 32 to be painted along the paint booth 22. Although described and illustrated in relation to a paint booth having a conveyor, it should be appreciated that the conveyor is not a requirement and could be omitted without departing from the scope of the subject disclosure. A grated floor 36 extends between the pair of side walls 26 to separate the paint booth 22 between a spray portion 38 disposed above the grated floor 36 and a paint filtration portion 40 disposed below the grated floor 36. The grated floor 36 defines a plurality of openings to allow the downdraft of air 25 to pass from the spray portion 38 to the paint filtration portion 40, while also allowing a paint booth operator 39 to move about the spray portion 38 of the paint booth 22 and access and service/clean equipment located inside the paint booth 22. A conveyor support 41 extends from each of the side walls 26 to provide structural support to the conveyor 34 and the grated floor 36.

[0026] As best illustrated in FIG. 1, a number of paint applicators 42 are typically placed in the paint booth 22 to apply paint particles to the vehicle 32. For example, the paint applicators 42 can include robot-arm-type paint applicators, rotary-bell type paint applicators or the like. As is known in the art, the paint applicators 42 can include a pair of paint applicators 42 that are typically placed on opposite sides of the central plane P and the conveyor 34 to allow the vehicle 32 to be painted from opposite sides at the same time. A plenum 44 extends along a top portion 46 of the paint booth 22 to introduce the downdraft of air 25 into the spray portion 38 of the paint booth 22 to capture and direct an overspray of paint particles that are not applied to the vehicle 32 in a downdraft of process air from the spray portion 38, through the grated floor 36 towards the paint filtration portion 40.

[0027] As best illustrated in FIGS. 1-4 and 6-10, the paint filtration portion 40 of the paint booth 22 includes the dry filtration system 24 for filtering the paint particles entrained within the downdraft of process air 25 as a flow of the downdraft air 25 travels in a flow path through the paint filtration portion 40 and towards an exhaust air chamber 48 disposed in fluid communication with the paint filtration portion 40 for subsequent routing to an exhaust air duct 50. As best illustrated in FIGS. 1-4, the exhaust air chamber 48 is disposed below the paint filtration portion 40, and the exhaust air duct 50 is disposed in fluid communication with the exhaust air chamber 48 and preferably extends outwardly from one of the side walls 26 of the paint booth 22 for allowing cleaned or filtered air to travel to an exhaust air fan for recirculation and potential later introduction into the plenum 44 as recycled downdraft of air.

[0028] The dry filtration system 24 includes at least one filter module 52 having a plurality of filter drawers 54 sequentially arranged relative to one another along the flow path of downdraft air through the respective filter module 52. For clarification, and as illustrated in the Figures, the flow path of downdraft air passes from the spray portion 38 through the paint filtration portion 40 (and directed through the at least one filter module 52) and then to the exhaust air chamber 48. Each of the filter drawers 54 defines a filter compartment 56 that houses at least one disposable filter 58 for filtering the downdraft air as it serially passes through the respective filter drawer 54. As best illustrated in FIGS. 1, 3-4 and 7, each of the plurality of filter drawers 54 are slideably connected to one of the side walls 26 of the paint booth 22 and slideable from a filtering (or closed) position wherein the filter compartment 56 is disposed within the paint filtration portion 40 of the paint booth 22 for filtering the downdraft of air with the at least one disposable filter 58 to a cleaning (or open) position wherein the filter compartment 56 is moved or slid to an outside environment of the paint booth 22 for allowing the at least one disposable filter 58 to be removed and replaced by the paint booth operator 39 such as after the disposable filter 58 has been filled or loaded up with filtered paint particles.

[0029] As best illustrated in FIG. 1, a filter drawer access platform 60 can extend along the side wall 26 of the paint booth 22 adjacent the at least one filter module 52 for allowing the paint booth operator 39 to individually and selectively slide the filter drawers 54 between the filtering and cleaning positions to change their respective disposable filters 58. Once a new disposable filter is placed in the filter compartment 56 by the paint booth operator 39, the filter drawer 54 is slid back into the paint filtration portion 40 of the paint booth 22 and back “on-line” for filtering the downdraft of air passing through the paint filtration portion 40. The filter module 52 having a plurality of slideable filter drawers 52 allows for the disposable filters 58 to be more easily and quickly replaced relative to the prior art designs which require the removal and replacement of the entire filter module 52 from the paint booth, which as explained previously requires the entire filter module 52 to be taken “off-line”, resulting in a more complicated and cumbersome filter replacement process. In contradistinction, the subject dry filtration system 24 including at least one filter module 52 having a plurality of slideable filter drawers 52 allows selective disposable filters 58 to be discretely and individually replaced by a paint booth operator 39, while leaving the other filter drawers 52 in the filter module 52 “on-line” and in the closed position for continuing to filter the paint particles from the downdraft of process air.

[0030] As best illustrated in FIGS. 3-4 and 7, a drawer slide 62 preferably establishes the slideable connection between the plurality of filter drawers 54 and the paint booth 22. For example, the drawer slide 62 can include a track 64 mounted on opposing drawer sides 66 and a rolling mechanism 68 mounted to the side wall 22 of the paint booth 22 in mating relationship with the track 64 to allow the filter drawer 54 to slide relative to the paint booth 22. However, placement of the track 64 and the rolling mechanism 68 can be interchanged, or other means of establishing the slideable connection can be utilized without departing from the scope of the subject disclosure. As further illustrated in FIGS. 6-7, at least one releasable locking mechanism 64 is disposed adjacent each filter drawer 54 for securing the filter drawer 54 in the filtering (closed) position, and preventing downdraft air and paint particles from escaping out of the filter drawer 54 and into the environment of the paint booth. For example, the releasable locking mechanism 64 is preferably comprised of a clamp. However other releasable locking mechanisms could be utilized without departing from the scope of the subject disclosure. When the paint booth operator 39 desires to change the disposable filter 58 disposed within the filter drawer 54, the locking mechanism 64 is released or unlocked to allow the filter drawer 54 to be pulled or slid from the filtering position to the cleaning (open) position for allowing the paint booth operator 39 to access the filter compartment 56.

[0031] As best illustrated in FIGS. 2, 6 and 8, each filter drawer 54 includes a drawer front 72 which extends transversely to the drawer sides 66 in parallel and spaced relationship to the central plane P of the paint booth 22. The drawer front 72 is disposed in overlaying and abutting relationship with the side wall 26 of the paint booth 22 when the filter drawer 54 is disposed in the filtration position to close the filter drawer 54 and isolate the paint filtration portion 40 from the environment of the paint booth 22. A seal 74 extends around a perimeter of the drawer front 72 and is disposed in abutting and compressed relationship with the side wall 26 when the filter drawer 54 is closed and the releasable locking mechanism 70 is locked to establish a seal between the filter drawer 54 and the side wall 26 of the paint booth 22 for preventing paint particles from escaping into the environment. At least one handle 76 extends outwardly from the drawer front 72 for allowing the paint booth operator 39 to pull and push the filter drawer 54 between the filtration (“closed”) and cleaning (“open”) positions.

[0032] The plurality of filter drawers 54 for the filter module 52 includes an upper filter drawer 54′ disposed adjacent the grated floor 36 and the spray portion 38 of the paint booth 22 and a lower filter drawer 54″ disposed adjacent the exhaust air chamber 48 and the exhaust air duct 50. Thus, the upper filter drawer 54′ in the filter module 52 is arranged to first receive the downdraft of air from the spray portion 38 of the spray booth for initially filtering the paint entrained in the downdraft of air with the at least one disposable filter 58′ housed within the respective filter compartment 56. Correspondingly, the lower filter drawer 54″ is arranged to lastly receive the downdraft of air for conducting a final filtration of the downdraft of air before the filtered downdraft air exits to the exhaust air chamber 48 and the exhaust air duct 50. Although the plurality of drawers 54 are illustrated as including only an upper filter drawer 54′ and a lower filter drawer 54″, other intermediate or middle drawers could be placed between the upper and lower filter drawers 54′, 54″, such as to increase the filtering capacity and capabilities of the filter module 52.

[0033] As best illustrated in FIGS. 8-9 and 11, the at least one disposable filter 58 housed in the filter compartment 56 of the upper filter drawer 54′ is preferably a cube filter 58′ defining a plurality of filter pockets 78. As further illustrated in FIGS. 8-9 the upper filter drawer 54′ preferably includes a plurality of disposable cube filters 58′ disposed in the filter compartment 56 to initially filter paint from the downdraft of air passing through the filter module 52. As best illustrated in FIGS. 10 and 12, the at least one disposable filter 58 housed in the filter compartment 56 of the lower filter drawer 54″ is preferably a pleat filter 58″ including a plurality of pleated sections 80. Similar to the upper filter drawer 54′, the lower filter drawer 54″ preferably includes a plurality of disposable pleat filters 58″ disposed in the lower filter compartment for conducting a final filtration of any residual paint particles or other contaminants from the downdraft of air before the filtered air exits the filter module 52 and is passed to the exhaust air chamber 48 and the exhaust air duct 50 for recirculation to the plenum 44.

[0034] As best illustrated in FIGS. 2-5, the at least one filter module 52 of the paint booth 22 preferably includes a plurality of filter modules 52 arranged between the entry and exit ends 28, 30 of the paint booth 22, with a first set of filter modules 52 disposed adjacent and along one of the side walls 26 and a second set of filter modules 52 disposed adjacent and along the other one of the side walls 26. In each of the first and second sets, the filter modules 52 are placed serially between the entry and exit ends 28, 30 of the paint booth 22 at a predetermined filter module spacing, such as with one filter module 52 placed per five foot length of the paint booth 22. However, other preferred filter module spacing could be utilized without departing from the scope of the subject disclosure. In this first and second set filter module arrangement, the downdraft of air exiting the spray portion 28 of the paint booth is directed to either side of the central plane P in the paint filtration portion 40 and downwardly towards the first and second set of filter modules 52 for filtering paint from the downdraft of air by the plurality of filter drawers 54.

[0035] As noted previously, after the downdraft of air has been filtered by the filter module(s) 52, the filtered air enters the exhaust air chamber 48 and is subsequently routed through the exhaust air duct 50 extending from the paint booth 22 to an exhaust air fan for recirculation. As best illustrated in FIGS. 2-4, at least one baffle assembly 82 is disposed in the exhaust air chamber 48 in fluid communication with the at least one filter module 52 for adjusting a flow of filtered air passing from the filter module 52 into the exhaust air chamber 48. For example, as best illustrated in FIG. 4, the baffle assembly 82 can include a plurality of baffles 84 which are adjustable by a motor 86 to control an amount of filtered air capable of passing from the filter module 52 to the exhaust air chamber 48.

[0036] The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.