Патент USA US2119282код для вставки
' May 31, 1938. J‘ E_ LUDWIG 2,119,282 SPRAY BOOTH Filed Aug. 24, 1936 INVENTOR. BY ' f/QJHNE. LUUWIE WQM ATTORNEY. ' 2,119,282 UNITED STATES‘ PATENT OFFICE Patented May 31, 1938 2,119,282 SPRAY BOOTH John E. Ludwig, Detroit, Mich, assignor to De Vilbiss Company, Inc., Toledo, Ohio, a cor poration of Ohio Application August 24, 1936, Serial No. 97,533 11 Claims. (Cl. 91—-60) My. invention pertains to ventilated spraying ganization and its method of operation together booths and more particularly to spraying booths of the type suitable for continuous production spraying. It is an object of my invention to provide a ventilated spraying booth comprising a forced alr‘inlet header having airldirecting means asso ciated therewith for directing a flow of air downwardly at relatively low velocity adjacent the object being sprayed and having high ve locity air projecting means for projecting a thin blast or sheet of air downwardly at high ve locity between the object and the low velocity air to aid the operator in applying a smooth 15 even coating of paint on the object and to protect him from inhaling the poisonous fumes thereof. It is a further object of my invention to pro vide a spraying booth comprising an air ventilat ' ing means wherein fresh air'is forced into the 20 spraying booth through an inlet header which comprises low velocityvdirecting outlets on the lower wall at opposite sides of the housing for directing a large volume of air downwardly at low velocity on opposite sides of the object being 25 sprayed, also narrow air projecting nozzles for projecting thin sheets of air downwardly at high velocity adjacent the opposite sides of the object between the object and the low velocity air,v and 3 additional air projecting means for projecting a sheet of air at high velocity across the ceiling between the downwardly projected air streams. The purpose of this ‘sheet of air at high velocity crossing the ceiling is not only to aid in carry ing o? fumes, but it is also useful in preventing the curtains of high velocity air from creating a vacuum adjacent the object being sprayed which with additional objects and advantages thereof will best be understood from the following de script-ion of a speci?c embodiment, when read in conjunction with the accompanying drawing, in which: , Fig. 1 is a side elevational view of my venti lated paint spraying booth partially sectioned and .broken away to clearly show the internal construction thereof and the circulation of air provided therein; Fig. 2 is an enlarged sectional view thereof showing the arrangement of the ,inlet header with the high velocity air projecting nozzles and the low velocity air directing grills; and 15 Fig. 3 is an elevational view of a low velocity ' air admitting grill provided in one side of the ventilating header. _ _ Referring more particularly to Figs. 1 and 2 of the drawing, my ventilated spray booth com 20 prises a housing enclosed by side walls I and 3 and a roof 5 through which the objects to be sprayed are continuously passed. The spray housing is provided with a ?oor ‘I spaced above the ?oor 9 of the factory and provided with aper 25 tured exhaust grills H and I3 which are spaced from the side walls i and 3 of the housing. ‘The exhaust grills H and I3 are extendedvhorizontally along the floor ‘I of the ‘housing, and may com prise any suitable open-work grating or the like. 30 The objects to be sprayed are transported through the spray booth‘over the floor "I and between the exhaust grills II and I3 in any convenientman ner as on an endless conveyor for example. For supplying ventilating air to the spray booth, I provide a motorized exhaust fan l5 would then otherwise tend to cause said high ' therein for drawing air through an air intake velocity air streams to hug tightly to the object conduit H which extends upwardly and passes being sprayed. This laterally projected air sub through the roof ill of the factory, where fresh sequent to its travel across the ceiling moves air is drawn in through an, elbow-2|. 40 _For properly distributing the ventilating air downwardly comparatively slowly between the downwardly projected high velocity air streams in the spray booth to carry the poisonous fumes permitting them to maintain a substantially di away from the workman and to aid him in prop - rect path from inlet to‘outlet. It is also anvobject of my invention to provide is01 a ventilated spraying booth comprising a ?oor having spaced exhaust apertures therein, an ex h'aust fan for drawing air rapidly from the booth through the exhaust'apertures, an air intake 60 fan having air directing means for directing a volume of fresh air downwardly on opposite sides of the object to be sprayed, and air projecting nozzles for directing thin sheets of air down wardly at high velocity adjacent the opposite 55 sides of the object between the object and the large volume of downwardly directed air where by the ventilating air is aided by gravity in carrying the obnoxious spray vapors awayfrom the operator. , a, . The invention, however, both as to it's or erly distributing the sprayed material to provide a smooth coat upon the object, the lower end of the intake air conduit i1 is provided with a trans versely disposed header 23 of ?at shallow con struction which is transversely disposed in the spraying booth over the objects to be sprayed.‘ The header is provided with inlet grills 25 and 21 which are mounted-in the lower wall of the header on opposite sides of the position occupied by the object being sprayed. For this purpose, any'suitable grill or open wire-work construc tion may be utilized. In the intermediate portion of‘ the lower wall of the intake header 23, I provide a closed panel '29 which is bulged upwardly in the middle to provide a convex surface disposed substantially over the position occupied by the object being 60 2 2,119,282 sprayed. The panel 29 extends the length of the header between the end walls thereof and is pro vided with marginal ?anges 3| and 33 at its left and right hand ‘edges respectively which are 5 turned upwardly in a substantially vertical posi tion. Parallel to and spaced from the upturned ?ange 33 at the right hand edge of the panel 29, I provide a vertical partition 35 which rises from _ the lower wall of the intake header. 10 The uppermost edge of the partition 35 is pro vided with a vane 39 which is turned horizontally toward the center of the header and is suitably spaced from the upper wall 31 of the header to de?ect the air and to de?ne an air inlet conduct ing passage of suitable size for receiving the air which passes downwardly through the grill 21 of the header with relatively "low velocity. The vertical panel-?ange 33 likewise carries at its upper edge vane portion 4| turned toward the 20 center of the header and which, with the vane 39, de?nes a passage for de?ecting and receiving the proper volume of air which passes down wardly through the duct defined between the ?ange 33 and the partition 35 into the spray 25 booth. The vertical walls 33 and 35 thus de?ne a nozzle for projecting a ?at blast or sheet of air downwardly with high velocity adjacent the side of the object being sprayed and between it’ and the larger volume of low velocity air which is 30 directed downwardly from the grill 21. For directing a sheet of high velocity air under and adjacent to the concave face of the closed panel 29, I provide a vertically disposed partition defusing globe of a suitable illuminating unit which, as will be readily understood, may be of suitable streamlined conformation to avoid set ting up eddies in the air stream. ' ‘Flor e?iciently exhausting the air from the spray booth and to aid the air projecting nozzles and grills in providing a smooth uniform circu lation of the air therein, I provide an exhaust fan 51 which is connected through a conduit 59 which connects into the air space defined under the 10 ?oor 1. At the left hand side of the exhaust grill II, a partition 61 is preferably inserted for restricting the exhaust passage de?ned there under. In operation, the objects to be sprayed are 15 moved through the spray booth in any suitable manner as upon a continuous conveyor (not shown), and as the attendant standing at one side of the spray booth sprays the object, the high velocity sheets of air 1| and 13 respectively 20 projected downwardly on opposite sides of the object tend to protect him effectively from inhal ing the poisonous vapors. If the paint spray is discharged strongly against the object being coated there is considerable re 25 bound of spray fumes which occasionally pene trate the high velocity streams. The addition of low velocity air between the object and high ve locity streams impedes the rebound and thereby assists the high velocity streams in preventing 30 the fumes from reaching the operator. Also the larger steams 15 and 11 of low velocity air projected downwardly from the grills 25 and wall which extends across the header in spaced 21 insure the sprayer a fresh supply of air at 35 relation from the left hand panel-?ange 3| and which, along its lower edge, is provided with a all times, and the circulation of the air above andaround the object at all times aids in properly horizontally disposed ?ange 45 which projects applying a smooth coat of the sprayed material . underand spaced from the closed panel 29. The air de?ecting ?ange 45 is provided along its edge 40 with an upturned vane portion 41 which is spaced substantially parallel with the under surface of the panel 29 whereby a thin jet or sheet of air is projected at high velocity along the under side of the panel 29 toward the jet of air which is 45 projected downwardly from the right hand side of the panel 29. The vertical partitions 3| and 43 are preferably provided at their upper edges with de?ecting vanes 44- and 46 respectively turned toward the center of the header. For projecting a high velocity sheet of air 50 downwardly adjacent the left hand side of the object being sprayed, I provide a vertical partl tion 49 which passes through the header in pare allel spaced relation from the ‘partition 43 and 55 de?nes a high velocity projecting duct therebe tween. This high velocity nozzle projects a sheet 00 65 70 75 upon the object. The jet of high velocity air coming through the passage between the vertical partitions 3| and 43, and which starts out in the direction of the arrows under the panel 29 becomes substan tially two’ low velocity streams of air passing downwardly on each side of the article being sprayed, due to the eddies or suction effect set 45 up between high velocity streams 1| and 13. The turns and narrow sections of the passage for the air passing between vane 41 and panel 29 prevent‘ the resulting air jet from having as much bulk or as high velocity as the vertical 50 sheets of air 1| and 13. It therefore is lacking in carrying power and is in?uenced by the down ward pull of the suction set up by the high velocity sheets 1| and 13. A portion of the jet near sheet 1| will be attracted by it and travel 55 with it to the exhaust opening while a major of air downwardly between the object being part of the jet will continue forwardly until it is sprayed and the larger volume of low velocity air turned downwardly by sheet 13. The general passing downwardly from the grill 25 at the left downward movement of the air jet is caused by hand side of the panel 29. The upper edge of . the pull of the air sheets 1| and 13 and has 60 the partition 49 is provided with a horizontally therefore less velocity than have these sheets. disposed ?ange 5| which projects 4 toward the The above advantages are also augmented by middle of the header and is spaced. from theupper gravity when the air inlets are above the outlets. wall 31 of the header for de?ning an air conduct In applicant's construction more effective protec ing passage suitable for passing a proper volume tion is provided for the attendant whereby he 65 of air from the conduit through the low velocity can closely and clearly see his work. grill 25. , Although I have shown and described a speci?c The low velocity air inlet grills 25 and 21 re embodiment of my invention, I am aware that spectively may be of any suitable open-work but many modifications are possible, my invention I preferably providea grill comprising‘a plurality therefore is not to be restricted except insofar 70 of metallic bars 53 securedtogether in parallel as it is limited by the prior art and the scope ’ relation by transversely‘ disposed rods 55, as of the claims. shown in Fig. 3. For providing e?icient illumi I claim: ‘ nation, a circular aperture 58 is provided in the 1. A ventilated spray booth having air supply center of the grill for mounting the re?ector and means for supplying fresh air to said booth, an 75 2,119,282 air inlet header associated therewith, low veloc ity directing means connected with said header for directing a large volume of air to flow in a path adjacent the object being sprayed, and an air projecting nozzle for projecting a sheet of air at high velocity between said large volume of moving air and the object being sprayed. 2. A ventilated spray booth having air supply means for supplying fresh air to said booth, an H) air inlet header connected therewith, an open grill in the lower wall of said header for direct ing a large volume of air ‘to ?ow in a path adja cent the object being sprayed, and an elongated air projecting nozzle opening from the lower face of said header for projecting a thin sheet of air to flow downwardly at high velocity between said large volume of downwardly ?owing air and the object being sprayed. - ' 3. A ventilated spray booth having air supply means for supplying fresh air to said booth, an air inlet header connected therewith, spaced air projecting nozzles for sheets of air at high veloc ity on opposite sides of objects to be sprayed and means for supplying lower velocity air between said sheets of air at high velocity. _ 4. A ventilated spray booth having an air inlet conduit for supplying fresh air to said booth, an air intake fan for forcing the air downwardly through said conduit, an air inlet header con 30 nected therewith, low velocity air directing means in the lower face of said header at opposite sides thereof comprising an open grill work for direct ing large volumes of air downwardly on opposite sides of the object being sprayed, elongated slots 35 in the lower face of said header at the adjacent edges of said spaced grills for directing thin sheets of air downwardly at high velocity adja 3 for directing large volumes of air downwardly outside of said high velocity sheets of air. 7. An air inlet header for ventilating a paint spraying booth comprising an elongated casing of ?attened conformation adapted to be con nected with an air inlet conduit, a solid ceiling panel extending across the middle of the lower wall, of said casing, air outlets of substantially broad area on opposite sides of said panel, and elongated slots extending along the opposite edges 10 of said panel adjacent said outlets for project ing thin sheets of air therefrom. 8. An air inlet header for ventilating a paint spraying booth comprising an elongated casing of ?attened conformation adapted to be con nected with an air inlet conduit, a solid ceiling panel extending across the middle of the lower wall of said casing, air outlets of substantially broad area in the lower face of said header on opposite sides of said panel, elongated slots along the opposite edges of said panel adjacent said outlets for projecting thin sheets of air there from at high velocities, spacedpartition walls projecting into said header from the opposite edges of said slot for de?ning an air projecting nozzle and passage connecting from the interior of said header. 9. An air inlet header for ventilating a paint spraying booth comprising an elongated casing of ?attened conformation adapted to be con nected with an air inlet conduit, a solid ceiling panel extending across the middle of the lower wall of said casing, air outlets of substantially broadarea in the lower wall of said header on opposite sides of said panel, elongated slots along the opposite edges of said panel adjacent said outlets for projecting thin sheets of air there cent the inside each stream of slow moving from, spaced partition walls projecting into said air. header from the opposite edge’ of said slot for _ 5. A ventilated spray booth having a housing de?ning an air projecting nozzle and passage 40 enclosed by side walls and a roof for de?ning the connecting from the‘ interior of said header, a space through which objects are transported to ceiling panel ventilating slot extending adja be sprayed, a ?oor in said housing, spaced ex cent one edge of said panel, and an air projecting haust apertures in said ?oor, for' drawing air -vane connected from the lower edge of said slot 45 from said booth at opposite sides of the sprayed spaced from and substantially parallel to the object, an exhaust fan connected for drawing lower face of said panel for-directing a thin sheet air therefrom, an air supply conduit for supply of air thereacross. ing fresh air in said housing, an intake fan asso 10. An air inlet header for ventilating a paint ciated therewith for forcing air downwardly spraying booth comprising a ?at casing having air outlets of broad area spaced in the lower wall 50 through said conduit, an air inlet header con nected therewith, low velocity air directing means on opposite sides of the header, a solid panel dis for directing streams of air downwardly adjacent posed in the lower face of said casing between opposite sides of the sprayed‘ object, and highv said outlets, said panel comprising a concave velocity air projecting means associated with lower face, an air projecting nozzle for project ing a thin stream of air at high velocity across 55 said header for projecting thin sheets of air down wardly at high velocity on both sides of the the lower face of said panel, spaced air project 40 sprayed object between the object and the slowly ing nozzles of elongated conformation disposed moving streams of air. 6. A ventilated spray booth having a housing 60 for enclosing a space through which objects may be passed for spraying comprising side walls and a roof, a floor in said housing, spaced exhaust apertures in said ?oor, an exhaust fan for drawing air rapidly from said housing through said ex 65 haust apertures, an air inlet conduit for supply ing fresh air to said housing, an air intake fan for forcing air downwardly through said con duit, an air inlet header connected therewith,‘ high velocity air projecting means associated therewith for projecting thin sheets of air down wardly at high velocity in spaced relation toward the spaced exhaust apertures in said ?oor, and low velocity air directing outlets in said header on opposite sides of said panel for projecting thin sheets of air downwardly at high velocity there from, and partition walls projecting inwardly in to said header from the opposite sides of said slots for de?ning air ducts or nozzles leading thereto and for providing sufficient back pressure to project the high velocity blasts of air while di recting a suitable volume of air to supply the large low velocity openings. 11. A ventilated spray booth having air supply means for supplying fresh air to said booth, an air inlet header associated therewith, a discharge nozzle for projecting a sheet of air at high veloc ity to one side of the object being sprayed and discharge means for projecting air at low velocity on both sides of the sheet'of high velocity air. JOHN E. LUDWIG.