Abstract:
A housing for a fan motor for a portable paint spray gun has a compartment accessible from the bottom in which an air hose is storable and provides an air path from the fan motor to the air hose having a minimum number of turns or curves between the motor exhaust port and the air hose. The housing enhances portability by providing convenient storage for the air hose when not in use and increases fan motor efficiency by reducing drag on the air flow by providing a relatively low resistance air path from the fan motor to the air hose.

Description:
SUMMARY OF THE INVENTION 
     This invention relates to a housing for a portable spray paint gun fan motor. The housing provides an air path having a minimum number of restrictions such as turns between the fan motor and the air hose to reduce drag on the air flow. The housing also provides a bottom opening compartment for air hose storage. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the housing. 
     FIG. 2 is a perspective view of the housing showing the bottom panel removed and hose storage within the housing. 
     FIG. 2a is a fragmentary exploded view of the top of the bottom panel showing the means for fastening the bottom panel to the housing. 
     FIG. 3 is an exploded view of the housing shown in FIG. 1. 
     FIG. 4 is an end elevational view of the housing. 
     FIG. 5 is a sectional view taken along line 5--5 in FIG. 4; and 
     FIG. 6 is a fragmentary section through the air exit fitting and upper dome assembly. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to FIGS. 1, 2, 3 and 4, a preferred embodiment of the housing 8 of the present invention is provided with a pair of generally planar vertical sides 10 and 13 and a pair of generally arcuate vertical sides 12 and 14. As may be seen, sides 10, 12, 13 and 14 are preferably, but not necessarily, slightly angled from vertical. A radius of the arcuate vertical side 12 is preferably, but not necessarily, less than a radius of the arcuate side 14. Together with an upper surface 16, these sides 10-14 define a generally elongate body 15 with an interior space 17 (see FIG. 2), the elongate body 15 having an inner perimeter 102. As seen in FIG. 5, the upper surface 16 defines a first slightly tapered cylindrical depression 18 and a second slightly tapered cylindrical depression 20. 
     The first depression 18 is divided into an upper and lower tapered sections 122 and 124, a lowest portion 123 of the upper tapered section 122 having a slightly larger radius than a highest portion 125 of the lower tapered section 124. A first annular horizontal ledge 126 is located between the upper tapered section 122 and the lower tapered section 124. 
     Similarly, the second depression 20 is divided into an upper and lower tapered cylindrical sections 128 and 130, a lowest portion 129 of the upper tapered section 128 having a slightly larger radius than a highest portion 131 of the lower tapered section 130. A circular disc 170 preferably rests on a second annular horizontal ledge 132 between the upper tapered section 128 and the lower tapered section 130 of the second depression 20. The circular disc 170 separates the upper tapered section 128 from the lower tapered section 130. 
     As shown in FIG. 2, a cylindrical surface 118 of the first depression 18 is disposed within the interior space 17. Likewise, a cylindrical surface 120 of the second depression 20 is disposed within interior space 17. The upper cylindrical section 128 of second depression 20, as seen in FIG. 1, is adapted and designed for removable retention of a spray gun assembly (not shown). 
     As shown in FIG. 5, the first depression 18 is adapted and designed to retain a fan motor 24. A filter 26 is preferably disposed within the lower section 124 of the first depression 18 to filter air before the air enters the fan motor 24. The filter 26 is disposed beneath a bottom vented filter cup 172 having an upper rim 176 which rests on the first horizontal ledge 126. A tubular gasket 178 rests between the fan motor 24 and the filter cup upper rim 176. The filter cup 172 extends about half way into the lower section 124. As shown in FIG. 2, the lower section 124 of the first depression 18 is vented with a first set of vents 29 to allow entry of air into the depression 18 in response to the vacuum created by the fan motor 24. The sides 10-14 are provided with a second set of vents 31 (FIGS. 1 and 4) to allow air flow from outside the housing 8 to reach the fan motor 24 through the second set of vents 31 and then through the first set of vents 29 and the filter 26 in response to a vacuum created by operation of the fan motor 24. (FIGS. 2 and 4). Polyurethane foam has been found to be a suitable material for filter 26. It is also to be understood that the air inlet for motor 24 is a central opening in its lower or bottom wall. 
     Referring again to FIG. 3, an annular gasket 28 of a suitable resilient material is located over a motor positioning plate 30 having an outer rim 268 preferably secured to the fan motor 24 such as by screws 31 with another gasket 33 of suitable resilient material located between plate 30 and motor 24 to produce a substantially air-tight seal therebetween. An inner dome 32 having a circular opening 34 is located over the annular gasket 28 to produce a substantially air-tight seal therebetween. An outer dome 36 is located over the inner dome 32. As is also shown in FIG. 6, the outer dome 36 defines a threaded bore 38 into which an externally threaded fitting 40 is screwed. An interior end 42 of the fitting 40 is adapted and designed to rest within the circular opening 34 of the inner dome 32 with a relatively air-tight seal between fitting 40 and inner dome 32 when the fitting 40 is threaded into the bore 38. A smooth surface 136 of a slightly tapered cylindrical section 234 located at the interior end 42 of the fitting 40 which is disposed within the circular opening 34 preferably creates the air-tight seal. An exterior end 43 of the fitting 40, which extends out of the threaded bore 38 of the outer dome 36, preferably has an exterior perimeter section 45 with wrench flats thereon. The fitting 40 defines a cylindrical passage 47 which communicates between the interior end 42 and the exterior end 43 of the fitting 40. The interior end 42 preferably has a grill 49 disposed across the cylindrical passage 49. 
     Referring now more particularly to FIG. 3, the outer dome 36, inner dome 32, annular gasket 28 and the motor positioning plate 30 are secured to the upper surface 16 surrounding the first depression 18 with screws 44. The screws 44 are received in holes 180 in an annular base 46 of the outer dome 36, holes 181 in an annular bottom plate 48 of the inner dome 32, holes 182 in the annular gasket 28, holes 183 in an annular rim 268 of the motor positioning plate 30 and holes 184 in the upper surface 16 around the first depression 18. As seen in FIG. 6, a downwardly extending circumferential lip 50 on the annular base 46 of the outer dome 36 covers the annular bottom plate 48 and the annular gasket 28. This construction causes air flow from the fan motor 24 to be directed into the inner dome 32, through the passage 47 of the fitting 40 with only a single turn of 90° in the air path. 
     Referring back to FIG. 3, the inner dome 32 is preferably formed of the annular bottom plate 48, a cylindrical center section 238, an upper section 244 and a horizontally disposed, slightly arched top portion 258. The cylindrical center section 238 extends upwardly from an inner edge 240 of the annular bottom plate 48. An upper end 242 of the cylindrical central section 238 has two horizontal portions 243 extending inwardly therefrom. Two vertical arcuate walls 246 extend vertically from the cylindrical central section 238. Two panel walls 248 extend upwardly between the arcuate walls 246 from an innermost edge 250 of each of the two horizontal portions 243. The panel walls 248 are comprised of a planar lower section 252 having a slight inward incline and an upper section 254 extending upwardly from an upper edge 256 of each planar lower section 252. The upper sections 254 preferably have a greater inward incline than the lower sections 252 as may be seen most clearly in FIG. 5. The arcuate walls 246 and the panel walls 248 are capped by the generally horizontally disposed top portion 258. One of the two arcuate walls 246 defines the circular opening 34 generally centered between the panel walls 248. 
     The outer dome 36 is preferably formed of an annular base 46, a slightly tapered cylindrical middle portion 262, and a convex ceiling portion 264. 
     Referring back to FIG. 3, the cylindrical middle portion 262 of the outer dome 36 extends upwardly from the inner circumference of the annular base 46. The ceiling portion 264 is located above and closes the cylindrical middle portion 262. 
     Referring to FIGS. 4 and 5, the outer dome 36 is preferably provided with an over-arching handle 72 disposed at a right angle to the threaded bore 38. The handle 72 has a first handle end 74 disposed near a first end 76 of the elongate body 15 and a second handle end 75 disposed between the first end 76 of the elongate body 15 and a second end 77 of the elongate body 15 near a center 78 of the elongate body 15. As seen in FIG. 3, the outer dome 36 also has an indentation 51 in its upper surface, the indentation 51 having a vertical wall 52 and a horizontal floor 54. FIG. 5 shows that the horizontal floor 54 has a switch opening 58 defined therein having an on-off switch 56 disposed therein. The on-off switch 56 has first and second sets of leads 62, 64 disposed within the outer dome 36. The first set of leads 62 also passes through the inner dome 32 through a lead opening 60 (shown in FIG. 3) in the inner dome 32 and connects to the fan motor 24. The lead opening 60 in the inner dome 32 is preferably sealed after the first set of leads 62 is inserted to make the lead opening 60 air-tight. Silicone caulk 186 has been found to be a suitable material for sealing opening 60. The second set of leads 64 connects the on-off switch 56 and an electrical cord 66. Referring to FIG. 5, the outer dome 36 defines an electrical cord opening 68 disposed beneath the first handle end 74 of the over-arching handle 72 in which a strain relief connector 70 is received. A set of cord connectors &#34;C&#34; connects the second set of leads 64 within the outer dome 36 to the electrical cord 66. 
     Referring now to FIGS. 2, 2a, and 5 the housing 8 is preferably provided with a bottom cover 80 having a generally planar section 82 and a first and second cylindrical well sections 84 and 86. The generally planar section 82 defines a waffle-like patterned grate of venting holes 266 communicating between a top 88 and bottom 90 of the bottom cover 80. The bottom 90 of the bottom cover 80 also has four support feet 92 disposed thereon. An outer perimeter 100 of the bottom cover 80 is adapted and designed to fit within the inner perimeter 102 of the elongate body 15 with the first and second cylindrical well sections 84 and 86 disposed upwardly and aligned with the first and second depressions 18 and 20 of the elongate body 15 respectively. 
     Disposed above the first cylindrical well section 84 is a first circular rotatable top plate 104 having a circumference slightly greater than a respective outer circumference of the first cylindrical well section 84. The first top plate 104 is provided with two horizontal beveled flanges 108 extending along a diameter of the first top plate 104. The first top plate 104 is disposable within a first annular bottom rim 112 of the first depression 18. The first annular bottom rim 112 of the first depression 18 defines two diametrically opposed notches 114 adapted and designed to receive the beveled flanges 108. Thus, the first top plate 104 is rotatable to position the beveled flanges 108 for insertion into radial notches 114 in the first annular bottom rim 112 of the first depression 18. Upon such insertion, the top plate 104 may be rotated up to 90 degrees. Upon rotation of the first top plate 104, the horizontal beveled flanges 108 are no longer aligned with the radial notches 114 and the first top plate 104 is retained within the first depression 18 against the first annular bottom rim 112 by the flanges 108. 
     The first cylindrical well section 84 preferably has a first annular backing lip 134 having a smaller inner radius than an inner radius of the first cylindrical well section 84. A first cylindrical blocking peg 136 extends upwardly from the first backing lip 134. The first top plate 104 defines a first arcuate channel 138 communicating between a front surface 140 and a back surface 142 of the first top plate 104. The arc of the first arcuate channel 138 is concentric with the first top plate 104. The first blocking peg 136 is disposed within the first arcuate channel 138 and limits axial rotation of the first top plate 104 to a range of 90 degrees. 
     A first backing disc 148 is disposed below the first top plate 104. The first backing disc 148 has a radius greater than the inner radius of the first annular backing lip 134, and less than the inner radius of the first cylindrical well section 84. As may be seen in FIGS. 2 and 5, a lower surface 156 of the first backing disc 148 is provided with a first blade 158 along a diameter of the first backing disc 148. An upper surface 157 of the first backing disc 148 has a raised center section 150 concentric with the first backing disc 148. The raised center section 150 has a radius slightly less than the inner radius of the first annular backing lip 134. Raised center section 150 has a thickness slightly greater than a thickness of a top surface 190 of the first annular backing lip 134 of the first cylindrical well section 84 such that when a top surface 190 of the first backing disc 148 is secured to top plate 104 by a pair of screws 160, 162, the assembly of disc 148 and top plate 104 is free to rotate with respect to lip 134. 
     The top surface 190 of the first raised center section 150 is provided with a pair of interlock pegs 152, 154 having a larger radius and a smaller radius respectively, upwardly extending from and symmetrically disposed on the raised center section 150 along a diameter of the raised center section 150. The first top plate 104 defines a larger interlock hole 144 and a smaller interlock hole 146 symmetrically disposed along a diameter of the first top plate 104. The larger and smaller interlock pegs 152, 154 are positioned for insertion into the larger and smaller interlock holes 144, 146 respectively. Such an interlocking peg and hole arrangement insures correct assembly of the first top plate 104 with the first backing disc 148. 
     Referring to FIG. 2a, the first top plate 104 is preferably affixed to the first backing disc 148 with first and second screws 160, 162 received through screw holes 161 in the top plate 104 and secured in screw holes 163 in the first backing disc 148. First blade 158 is aligned over a pair of bosses 270 containing screw holes 163 to provide additional strength. 
     Referring to FIGS. 2 and 5, the second cylindrical well section 86 is removably attachable to the second depression 20 using a second top plate 106 having a second pair of beveled flanges (not shown) inserted into a second pair of radial notches 115 in the same manner in which the first top plate 104 of the cylindrical well section 84 is removably attachable to the first depression 18. 
     As shown in FIG. 2, the inner perimeter 102 of the elongate body 15 is preferably provided with a set of bottom stop ridges 166 to rest against the bottom cover 80 and prevent the bottom cover 80 from deflecting inward into the interior space 17 of body 15. 
     An air hose 168 is storable within interior space 17 by wrapping the hose 168 around the cylindrical surfaces 118, 120 of the first and second depressions 18, 20 and then attaching bottom cover 80 to body 15 by inserting both pairs of horizontal beveled flanges 108, (not shown), into their respective pairs of radial notches 114, 116 and rotating the first blade 158 and a second blade 159 to secure the bottom cover 80 in place. 
     Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.