US3566548A

US3566548A - Dust removal construction for a belt-type sander

Info

Publication number: US3566548A
Application number: US840773A
Authority: US
Inventors: Jacobus J Beckering; Allen G Beares
Original assignee: Black and Decker Manufacturing Co
Current assignee: Black and Decker Corp
Priority date: 1967-01-18
Filing date: 1969-07-10
Publication date: 1971-03-02
Anticipated expiration: 1988-03-02

Abstract

THIS INVENTION RELATES GENERALLY TO PORTABLE, POWER DRIVEN TOOLS, AND PARTICULARLY TO AN IMPROVED, PORTABLE, BELT-TYPE SANDING, POLISHING OR BURNISHING DEVICE AND HOUSING AND HANDLE CONSTRUCTION THEREFORE. MORE SPECIFICALLY, THE DISCLOSURE TO FOLLOW DESCRIBES A PORTABLE, POWER DRIVEN SANDING, BURNISHING OR POLISHING DEVICE OF THE TYPE HAVING A HOUSING AND SPACED DRIVE AND IDLER PULLEYS ROTATABLY SUPPORTED ON THE HOUSING FOR ROTATION ABOUT PARALLEL AXES. AN ELECTRIC MOTOR SUPPORTED UPON THE HOUSING DRIVES THE DRIVE PULLEY AND AN ENDLESS BELT ENTRAINED OVER THE DRIVE AND IDLER PULLEYS. THE BELT IS SUITABLY FORMED FOR SANDING, BURNISHING OR POLISHING AND THE BOTTOM OF THE HOUSING IS OPEN SO THAT THE WORKING SURFACE OF THE BELT IS EXPOSED AT THIS AREA. THE HOUSING DESCRIBED, AS WELL AS A HANDLE DETACHABLY SECURED THERETO, ARE OF CLAM-SHELL LIKE CONSTRUCTION SERVING TO TRAP VARIOUS COMPONENTS OF THE DEVICE IN PLACE. IN ADDITION, THE HANDLE, THE HOUSING, AND A DETACHABLE COVER PROVIDE A PASSAGEWAY THROUGH WHICH DUST MAY BE REMOVED UNDER THE ACTION OF A SUCTION FAN. A DETACHABLE DUST BAG MAY BE PROVIDED TO COLLECT THE DUST.

Description

March 2,1971 J. .1. BECKERING ET Q 3,566,548

DUST REMOVAL CONSTRUCTION FOR A BELT-TYPE SANDER Original Filed Jan. 18, 1967 4 Sheets-Sheet 203 V 29 '7 F I76 INVENTORS W8 -9 JACOBUS J. BECKERING W ALLEN G. BEARES l8 mo 203 I53 ATTORNEY March 2, 1971 BECKERlNG ET AL 3,566,548

DUST REMOVAL CONSTRUCTION FOR A BELT-TYPE SANDER 4 SheetS-Sheet 5 Original Filed Jan. 18, 1967 JACOBUS J. BECKERING ALI; N G. BEARES March .2, 1971 J. J. BECKERING ET AL DUST REMOVAL CONSTRUCTION FOR A BELT-TYPE SANDER 4 Sheets-Sheet 4 Original Filed Jan. 18, 1967 '94 FIG. :2 3e 20? FIG. l5

INVENTORS JACOBUS J. BECKERING ALL N G BEARES mJ ATTORNEY United States Patent O 3,566,548 DUST REMOVAL CONSTRUCTION FOR A BELT-TYPE SANDER Jacobus J. Beckering, Greenville, S.C., and Allen G. Beares, Towson, Md., assiguors to The Black and Decker Manufacturing Company, Towson, Md. Original application Jan. 18, 1967, Ser. No. 610,191, now Patent No. 3,474,575, dated Oct. 28, 1969. Divided and this application July 10, 1969, Ser. No. 840,773

Int. Cl. B24b 23/00, 55/06 U.S. Cl. 51170 19 Claims ABSTRACT OF THE DISCLOSURE This invention relates generally to portable, power driven tools, and particularly to an improved, portable, belt-type sanding, polishing or burnishing device and housing and handle construction therefor. More specifically, the disclosure to follow describes a portable, power driven sanding, burnishing or polishing device of the type having a housing and spaced drive and idler pulleys rotatably supported on the housing for rotation about parallel axes.

An electric motor supported upon the housing drives the drive pulley and an endless belt entrained over the drive and idler pulleys. The belt is suitably formed for sanding, burnishing or polishing and the bottom of the housing is open so that the working surface of the belt is exposed at this area. The housing described, as well as a handle detachably secured thereto, are of clam-shell like construction serving to trap various components of the device in place. In addition, the handle, the housing, and a detachable cover provide a passage-way through which dust may be removed under the action of a suction fan. A detachable dust bag may be provided to collect the dust.

This application is a division application Ser. No. 610,191, filed Jan. 18, 1967, now Pat, No. 3,474,575.

SUMMARY OF THE INVENTION An important object of the present invention is to provide an improved housing and handle construction for portable sanding, polishing and burnishing devices and the like which construction is adapted for ready use with a dust removing and collecting device.

Still another object of the present invention is to provide an improved portable sanding, polishing or burnishing device embodying a housing and handle construction of the above character wherein provision is made to activate or deactivate a dust removing and collection device integrated therewith with a minimum of effort and part change and without disturbing or dismantling the handle or housing.

Still another object of the present invention is to provide an improved portable device of the above character wherein interchangeable parts capable of being formed from a single die are employed to activate and deactivate the dust removing and collecting device.

Further objects include the provision of an improved portable device and housing and handle construction therefor of the character described which is relatively inexpensive to manufacture, rugged and light-weight in construction, and safe and reliable in use.

Other objects and advantages of the present invention will become more apparent from a consideration of the following detailed description taken in conjunction with the drawings in which:

Patented Mar. v2, 1971 "ice FIG. 1 is a side elevational view of a portable sanding device embodying the present invention;

FIG. 2 is a sectional view of FIG. 1 taken along the line 22 thereof;

FIG. 3 is a sectional view of FIG. 2 taken along the line 33 thereof;

FIG. 4 is an exploded, perspective view illustrating the clam shell housing and handle construction of the present invention, shown with the internal parts removed for clarity;

FIG. 5 is a sectional view of FIG. 1 taken along the line 5-5 thereof;

FIG. 6 is a fragmentary elevational view of the other side of the device as shown in FIG. 1, and seen with the gear cover removed;

FIG. 7 is a sectional view of FIG. 6 taken along the line 77 thereof;

FIG. 8 is a sectional view of FIG. 6 taken along the line 8-8 thereof;

FIG. 9 is a sectional view of FIG. 1 taken along the line 9--9 thereof;

FIG. 10 is a side elevational view illustrating a preferred form of gear cover which is employed with the dust collection construction;

FIG. 11 is a view similar to FIG. 10 illustrating a modified form of gear cover which is employed without the dust collection construction;

FIG. 12 is a plan view of the upper housing frame member shown in FIG. 4 and looking in the direction of the arrows 12--12 thereof;

FIG. 13 is an enlarged, sectional view of the structure of FIG. 1 taken along the line 1313 thereof;

FIG. 14 is an enlarged plan vie-w of the motor housing cover shown in FIG. 4 and looking in the direction of the arrows 1414 thereof; and

FIG. 15 is a sectional view of the structure of FIG. 13 taken along the line 1515 thereof.

BROAD STATEMENT OF THE INVENTION Broadly described, the present invention includes a housing having a side wall, a drive motor supported by said housing and having an output shaft, a drive pulley supported by said housing and having a pulley shaft rotatable therewith, said output shaft and said pulley shaft extending outwardly of said side wall, transmission means outside said housing side wall interconnecting said output and drive shafts, a cover detachably secured to said side wall and defining therewith an enclosure in which said transmission and the outer ends of said shafts are disposed, idler pulley means supported by said housing, endless belt means entrained over said drive pulley and idler pulley means and having a longitudinal working run, dust removal passage means originating adjacent the rearward end of said belt working run and extending between said cover and said side wall and disposed wholly radially outwardly of said enclosure and beside and substantially in the same plane as said enclosure, and suction means communicated with said passage means for drawing dust from the rearward end of said belt working run through said passage means.

In still another aspect, the present invention includes a housing having a side wall, a drive motor on said housing, drive and idler pulley means on said housing and disposed to the inside of said side wall, said drive pulley means and said drive motor each having rotatable shafts extending to the outside of said housing side wall, transmission means to the outside of said side wall and interconnecting said shafts, cover means for said transmission means detachably secured to said side wall an endless belt entrained over said drive and idler pulley means and having a longitudinal working run, means on said housing adjacent the rearward end of said belt working run defining an inlet opening, said inlet opening extending transversely of said working run and to one side of said housing, said cover overlaying said inlet opening at said housing one side and having means associated therewith blocking passage of material out of said inlet opening, said cover being adapted, when said blocking means is omitted therefrom, to permit free passage of material out of said inlet opening, suction means on said housing, dust removing passage means formed between said housing side wall and said cover, and outside said transmission, interconnecting said suction means and said inlet opening when said blocking means is omitted, whereby dust formed during 'use of said device may be withdrawn through said inlet opening and said passage means.

DETAILED DESCRIPTION Referring now more specifically to the drawings, a compact belt sander embodying the present invention is illustrated generally at 11 in FIGS. I3 and is seen to include a housing 13 having a handle assembly 15 secured thereto. A drive motor 17 is positioned Within the housing 13 and is adapted to be connected to a power source through a line cord 19 and is controlled by a trigger switch 21. The motor 17 is drivingly interconnected to a drive pulley 23 positioned within the housing 13 and preferably to the rear of the motor. An idler pulley 25 is also positioned within the housing 13 and is disposed forwardly of the motor 17. An endless belt 27, suitably formed for abrading, polishing or burnishing, is entrained over the

pulleys

23, 25 and has upper and lower runs 27A, 27B above and below the motor 17. The belt 27 moves with rotation of the drive pulley 23, the latter having a friction sleeve 28 thereon, and turns the idler pulley 25. The bottom of the housing 13 is substantially completely open so that the belt lower run 27B is exposed, the latter being backed by a smooth shoe plate 26. Thus, when the motor 17 is energized, the pulley 23 turns and by friction causes the belt 27 to move and the pulley 25 to turn whereupon the device is ready for .use.

Turning now to FIGS. l-4 and 12-l4, the housing 13 is seen to include detachably secured, mating, upper and

lower frame members

29, 31 which preferably, but not necessarily, are constructed of cast aluminum. The upper frame member 29 has an elongated top 32 and side wall portion 33 while the lower frame member 31 has an elongated side Wall portion 34 which is substantially co extensive with and mates with the side wall potrion 33. A motor housing 36 comprising a mating pair of substantially semi-cylindrical

motor housing portions

37, 39 are rigid with and extend inwardly from the

side wall portions

33, 34, respectively. The

motor housing portions

37, 39 preferably are constructed integral with the

frame members

29, 31, respectively, and are disposed to closely interfit when the

side wall potrions

33, 34 are juxtaposed. A separate motor housing cover 35 forms substantially a continuation of the motor housing portion 37 and mates with the inner end of the motor housing portion 39 for a purpose hereinafter set forth. Screws 40, 41 extend through

bosses

36, 38 in the side wall potrion 33 and motor housing portion 37 and are threaded into

openings

44, 46 in the side wall portions 34 and motor housing portion 39, respectively, to secure the frame members together. The cover 35 is secured in place on the motor housing portion 39 by screws 42 which extend through the former and are threaded into openings 48 in the latter.

The motor 17 shown is a conventional universal type and is disposed substantially completely within the motor housing 36 and has an armature shaft 43 supported fore and aft by spherical sleeve or

needle bearings

45, 47 trapped in

recesses

49, 51 which are shaped complementary to the

bearings

45, 47 and are formed at the parting plane between the frame member

side wall portions

33, 34 and between the motor housing portion 39 and the cover 4 35, respectively. Of course, if straight type bearings are employed, the

recesses

49, 51 would be correspondingly straight in configuration.

An armature windings assembly 53 is fitted to the shaft 43 and is rotatable within a field windings sub-assembly 55, the latter being fixed within the

motor housing members

37, 39. A commutator 57 is fixed to the shaft 43 for rotation therewith and is located between the armature windings assembly 53 and the bearing 47. A pair of

electrical brushes

59, 61 are engageable with the commutator 47 and are supported in

brush holders

63, 65, respectively.

As shown in FIG. 13, at least one and preferably both the motor housing portion 39 and the motor housing cover 35 are formed with recess means 64, 66 at the parting plane therebetween which receive and trap the brush holders 63, in place. In this manner, the

brush holders

63, 65 can be removed and the

brushes

59, 61 replaced simply by removing the motor housing cover 35 and does not require disassembly of any of the other housing components. A fan 73, which serves both to draw cooling air past the motor 53 and to assist in dust collection during use of the device, is pressed on the armature shaft 43 adjacent the bearing 45 and rotates freely in a substantially cylindrical cavity 68 formed in the

motor housing portions

37, 39.

To energize the motor 17, the

brushes

59, 61, which are biased against the commutator 57, are connected to a pair of

leads

56, 58, the former being a power lead from the line cord 19 and the latter being connected to the motor field, Another lead 60 interconnects the field and the trigger switch 21 which in turn is connected to another other power lead 62 carried by the line cord 19 so that when the line cord is plugged into an electrical source and the switch 21 closed, the motor 17 is energized and the armature shaft 43 rotated in the usual manner.

The other end of the armature shaft 43 extends beyond the bearing 45 and outside the housing 13, as shown in FIG. 2, and is formed With pinion teeth 75, or, alternatively, has a pinion fixed thereto. An idler gear 77 is rotatably supported on a stub shaft 81 pressed into the side wall portion 34 and is engaged by the pinion teeth so as to be driven thereby. A retainer 83 holds the idler gear 77 in place on the shaft 81. The idler gear 77 also engages an intermediate gear 85 held in place by a retainer 87 on a stub shaft 89 also pressed into the housing member 31. An intermediate pinion 93 is formed on a hub of the gear 85 or is keyed thereto so as to rotate therewith and drivingly engages a spindle gear 95 which is keyed to a pulley shaft 97 and held in place thereon by a screw 99 and a lock washer 101. The pulley shaft 97 extends substantially parallel to the armature shaft 43 and through a mating pair of generally semi-cylindrical shaft supports 111, 113 depending inwardly from the

side wall portions

33, 34, respectively, and preferably integral therewith. A pair of sleeve or needle *bearings 103, are trapped in axially spaced,

cylindrical recesses

107, 109 formed at the parting plane between the shaft supports 111, 113 and rotatably support the pulley shaft 97. A plurality of screws 115 detachably secure the supports 111, 113 and assist in holding the

frame members

29, 31 together.

The drive pulley 23 is provided with a substantially central opening therethrough 117 which receives the shaft 97 in press fit relation so that the pulley 23 turns with rotation of the shaft 97. The drive pulley 23 is disposed closely adjacent the rearward end of the motor housing 36 while the idler pulley 25 is disposed closely adjacent the forward end of the motor housing. The idler pulley 25 is rotatably supported by sleeve or needle bearings 119, 121 upon a shaft 123 carried by a generally U-shaped pulley bracket 125. The shaft 123 is formed with splines 127 which interferingly engage the bracket to prevent shaft rotation. The pulley bracket 125 is supported upon a support bracket 129 for pivotal and longitudinal movement relative thereto by a pivot pin 131 pressed into openings in rearwardly extending

legs

133, 135 on the pulley bracket 125 and extending freely through longitudinal slots (not shown) in

arms

141, 143 forming a part of the support bracket 129. The idler pulley 25 is normally held in the position shown in FIGS. 2 and 3 by a torsion spring 145 entrained around the pin 131 and having spring lugs engaging the bracket 125 so that belt 27 entrained over the drive pulleys 23, 25 is tensioned. However, to remove and/or replace the belt 17, the idler pulley 25 is moved toward the drive pulley by manipulating a lever device 147 which is pivoted on the side wall portion 34 and operably connected to the pulley bracket 125 and adapted to move it and the idler pulley 25 carried thereby rearwardly or toward the left against the force of the spring 145 (FIG. 2). This lever device 147 forms no part of the present invention but is illustrated and described in detail in the Beckering et al., US. Pat. No. 3,393,573, granted July 23, 1968, and owned by the assignee of the present application, so that reference may be made thereto for a better understanding thereof.

In addition, the idler pulley 25 is adjustable in a plane transverse to the direction of belt movement by manipulating a tracking device 149. This device includes a knob 148 threaded on the end of the shaft 123 and adapted to move the shaft axially and pivot the bracket 125 about the pin 131 to maintain the center of pressure on the pulley 25 aligned with the center of resistance on the belt 17. Again, this device 149 forms no part of the present invention but for a better understanding thereof, reference may be made to the Beckering U.S. Pat. No. 3,429,- 078 granted Feb. 25, 1969, and owned by the assignee of the present application.

As described above, the housing 13 is formed of at least two parts, i.e.

frame members

29, 31, adapted to mate along substantially a longitudinal, horizontal plane which intersects the

armature shaft bearings

45, 47 and the pulley shaft bearings 103. Thus, the

frame members

29, 31 form a clam-shell like construction which, when open, permits easy removal and/or replacement of any of the motor and drive pulley components and, when closed, secures these parts in place in a simple but highly effective manner without requiring special fasteners and/ or supports for any of these components. In addition, this clam-shell like configuration eliminates the need for expensive machining techniques and therefore contributes greatly to an overall reduction in cost of the device. The use of the separate motor housing cover 35 maintains the basic clam-shell arrangement and, in addition, permits easy removal and/or replacement of the motor brushes 59, 61 while leaving the rest of the housing 13 intact.

Along with the motor 17 and the components of the drive pulley 23, the clam-shell housing 13 traps the belt tensioning and tracking

operating mechanisms

147, 149 in place therebetween in a simple, facile manner which again requires no special fasteners or supports. Furthermore, the

brackets

125, 129 which provide support for the idler pulley 125, as well as to facilitate both tensioning and tracking movement thereof,'are in turn supported directly on the frame member 31 so as to be easily removable if desired when servicing the motor 17 and the drive pulley components.

Of substantial importance in the construction thus far described is the location of the motor housing 36 and the motor 17 between the belt runs 27A, 27B, and the particular disposition of the motor 17 together with the arrangement of the transmission connecting the motor 17 and the drive pulley 23. Thus, by locating the motor 17 between the

pulleys

23, 25 and the belt runs 27A, 27B, the device 11 is made more compact and its center of gravity lowered somewhat making it considerably easier to handle. Furthermore, as shown, the motor axis is disposed transverse to the belt runs 27A, 27B, and generally parallel to the axes of the

pulleys

23, 25. This, together with the disposition of the gear transmission outside the housing 13 greatly decreases the space between the

pulleys

23, 25 required by the motor 17 as compared with one where the motor axis is disposed along the belt runs and the transmission located Within the housing. Thus, a relatively large, more powerful motor can be employed without significantly increasing the size of the device thereby facilitating a highly efiicient, easily handled tool.

The frame member top 32 has a relatively large slot or opening 151 formed therein overlaying the motor housing 36 and the pulley shaft supports 111, 113. This opening 151 advantageously exposes all of the screws 41, for easy access in assembling and disassembling the housing 13, and in addition, contributes materially to reducing both the overall weight and cost of the device 11. In assembly, the opening 151 is covered by a forward portion of the handle assembly 15, to be described in detail below, which advantageously extends to a forward region of the housing 13. The handle assembly 15 is constructed of a considerably lighter weight material than the housing 13 so that a considerable weight saving is achieved.

Turning now to FIGS. 1, 3 and 4, the handle assembly 15 is seen to include handle and handle

cover portions

153, 155 detachably secured by screws 156 along a longitudinal, vertical plane. Like the housing 13, the handle assembly 15 forms essentially a clam-shell like construction and traps the trigger switch 21 and the line cord 19 in place therebetween.

As shown in FIGS. 3 and 4, the handle and handle

cover

153, 155 are formed with mating rear

handle grip portions

152, 154, respectively. The trigger switch 21 is trapped between the

grip portions

152, 154 and includes an apertured mounting plate 158 adapted to fit on a pair of posts 160 formed in the handle grip portion 152 and held in place thereon by a tubular boss 162 formed on the handle grip portion 154. A trigger 164 is pivoted on the mounting plate 158 and extends through an aperture 166 in the

handle grip portions

152, 154 for easy access by the operator during use of the device. The line cord 19 extends through an aperture 168 formed at the juncture between the handle and handle

lever

153, 155 and has a protective sheath 170 encased therearound and provided with a flange 172 adapted to snugly fit in a recess 174 also at the handle and handle cover juncture. In addition, the handle and handle

cover

153, 155 may be formed with

portions

140, 142, respectively, removed to receive a two-speed switch (not shown). Advantageously, the handle and handle

cover

153, 155 with or without the

portions

140, 142 removed, can be molded using the same basic dies, for example by employing removable die pins as is customary in the art.

The handle and handle

cover

153, 155 partially embrace the housing 13 and are secured thereto in a novel, simple and effective manner calculated to provide both utility as Well as simplicity of design. Thus, the handle and handle

cover

153, 155 have forwardly projecting, upwardly facing

ledges

167, 169 adapted to seat beneath downwardly facing

ledges

171, 179 formed on dependent, slotted

ears

180, 182 at the rearward end of the frame top 32. The forward portions of the handle and handle

cover

153, 155 are adapted to receive an upwardly projecting lug 177, integral with the frame top 32, therebetween. A mounting screw 175 extends through an opening in the handle cover 155 and an opening in the lug 177 and is threaded into an opening in the handle 153 (see FIG. 5). In addition, a mounting bolt 173 extends through

bosses

176, 178 in the handle and handle

cover

153, 155, respectively, and through the slotted

ears

180, 182 and is threaded into a nut 184 trapped in the boss 176. The screw 175 and the bolt 178 of course supplement the screws 156 in hoiding the handle 153 and handle cover 155 together; however, it will be apparent that when it is desired to remove the handle assembly 15 before dismantling the housing 13 for service or replacement of the motor or drive pulley assembly, only the screw 175 and the bolt 173 are removed whereupon the handle assembly 15 is detachable from the housing 13 but is still intact. In addition to the

rear handle portions

152, 154, the handle and handle

cover

153, 155 are pro vided with mating front handle

portions

163, 165 which, together with the former, facilitate easy two-handed operation and control of the device 11.

An important feature of the device of the present invention is the adaptability thereof to use with or without a dust collecting device. Stated another way, the device of the present invention employs a basic construction and arrangement susceptible to relatively rapid and inexpensive conversion from inactive to active dust collection. It will be appreciated that some part change, modification and/ or replacement will be required when converting the device; however, according to the present invention, a minimum of part change is required and those parts involved are not only fully interchangeable on the basic device 11, but also are adapted to be molded using a single, basic die. Furthermore, the dust collecting device includes an integrated bag assembly quickly and easily attachable and detachable from the basic device 11 and which requires no separate, unsightly or burdensome features or supports.

Turning now to FIG. 2, the fan 73 is seen to include oppositely disposed sets of

blades

183, 185 separated by a generally disc shaped baffle 181, the baffle being disposed closely adjacent the wall of the cylindrical cavity 68 so as to effectively divide the latter into two chambers. The blades 183 serve to draw cooling air axially past the motor 17 and to this end, the inner radial wall of the cavity 68 has a relatively large aperture 189 surrounding the armature shaft 43. This cooling air is then exited through arcuately spaced openings 187 formed in the peripheral wall of the cavity 68. The fan blades 185 serve to draw dust from the workpiece and delivers it to a dust bag when the dust collecting construction is active and are correspondingly inactive when the dust collection construction is inactive.

During rotation of the fan 73, the blades 185 draw air through openings 190 formed in the outer radial wall of the cavity 68 (see FIGS. 4 and 6). A gear cover 191 is fixed to the housing 13 by screws (not shown) adapted to extend through aligned

bosses

193, 194 in the cover 191 and the

side walls

33, 34, respectively. The cover 191 has an outer substantially peripheral lip 195 which seats snugly in a recess 197 formed in the frame

member side walls

33, 34. A continuous inner lip 199 formed on the gear cover 191 seats tightly on a continuous lip 201 formed on the frame

member side walls

33, 34 and circumscribing the transmission gears 75, 77, 85, 93, 95 so as to define an enclosure for and seal off these gears when the cover 191 is in place. In addition, the engaged

lips

199, 201 and lip and

recess

195, 197 define a dust passage 202 therebetween which is Wholly radially outwardly and beside and substantially in the same plane as the gear enclosure, and which communicates with the suction openings 190 and through which dust is adapted to be transported.

Dust is removed from the work during use of the device through an intake slot 203 located in the bottom of the handle and handle

cover

153, 155 beneath the

ledges

167, 169 and adjacent the rear end of the lower belt run 27B. The intake slot 203 communicates with an inlet pocket 205 in the gear cover 191 which, in the embodiment shown in FIGS. 1-10, is open to the dust passage 202. The suction generated by the fan blades 185 is communicated to the passage 202 and the intake slot 203 so that during use of the device, dust is drawn into the intake slot 203 and inlet pocket 205, through the passage 202 and into the fan blades 185 through the openings 190.

The dust drawn into the fan blades 185 is thrown radially outwardly by centrifugal force through an outlet passage 207 formed in the peripheral wall of the cylindrical cavity 68 (FIG. 7). The gear cover 191 has an integral outlet tube 209 communicating with the outlet passage 207. A dust bag assembly 210 including a dust bag 215 is provided with an exhaust tube 211 communicated with the bag 215 and adapted to be inserted in the outlet tube 209 and retained therein by a clip spring 213. Thus, the dust blown by the fan blades through the outlet passage 207 is also blown through the outlet tube 209 and exhaust tube 211 and into the bag 215. The bag assembly 210 is removable simply by pulling on the exhaust tube 211 with a force sufficient to release the spring 213 from the outlet tube 209.

If it is desired to use the device 11 without the dust collecting device, a modified gear cover shown generally at 219 (FIG. 11) is substituted for the gear cover 191. The modified gear cover 219 is identical to that shown at 191 with the exception that the modified cover 219 is provided with a wall 221 across the top of the inlet pocket 205 and which is adapted to seat tightly against an outer horizontal edge 220 of the ledge 167 on the handle 153. The cooperating wall 221 and edge 220 seal the inlet pocket 205 and therefore the intake slot 203 from the dust passage 202 and the suction effect of the fan blades 185 so that no dust is picked up when the modified cover 219 is used. In addition, the outlet tube 209 on the modified cover 210 is sealed off by an integral Wall 223.

It will be appreciated that when it is desired to convert from active to inactive dust collection, or vice-versa, all that is necessary is to interchange the

covers

191, 219 and add or remove the dust bag assembly 210 as is the case. This construction is advantageous not only from the viewpoint of providing a relatively easy and inexpensive change over from active to inactive collection, but also for the more important reason that the gear covers 191, 219 can be formed using basically the same die. Thus, removable inserts are used in the die to alternatively form the wall 121 and the outlet tube wall 223 so that in this way, manufacturing costs are kept to a minimum.

By the foregoing, there has been disclosed an improved housing and handle construction for portable sanding devices and the like calculated to fulfill the inventive objects hereinabove set forth, and while a preferred embodiment of the present invention has been illustrated and described in detail, various additions, substitutions, modifications and omissions may be made thereto without departing from the spirit of the invention as encompassed by the appended claims.

We claim:

1. A portable sanding polishing or burnishing device comprising a housing having a side wall, a drive motor supported by said housing and having an output shaft, a drive pulley supported by said housing and having a pulley shaft rotatable therewith, said output shaft and said pulley shaft extending outwardly of said side wall, transmission means outside said housing sidewall interconnecting said output and drive shafts, a cover detachably secured to said side wall and defining therewith an enclosure in which said transmission and the outer ends of said shaft are disposed, idler pulley means supported by said housing, endless belt means entrained over said drive pulley and idler pulley means and having a longitudinal working run, dust removal passage means originating adjacent the rearward end of said belt working run and extending between said cover and said side wall and disposed wholly radially outwardly of said enclosure and beside and substantially in the same plane as said enclosure, and suction means communicated with said passage means for drawing dust from the rearward end of said belt working run through said passage means.

2. A construction as defined in claim 1 wherein saidq cover is generally concave in cross-sectional configuration, said cover and side wall being formed with, mutually; engageable, rib means extending substantially ,continuously around said transmission and, the outer-ends of said shafts.

3. A construction. as. definedlin. claim 2 where n S id rib means is spaced inwardly from the outer peripheral edge of said cover, and where-in said peripheral edge snugly engages said side wall which, together with said engaged rib means, defines said passage means.

4. A construction as defined in claim 1 wherein said suction means is positioned within said housing side wall and is communicated with said passage means by at least one opening in said side wall.

5. A construction as defined in claim 4 wherein said suction means includes a fan rotatable with said motor shaft and positioned within said side wall.

6. A construction as defined in claim 1 wherein said drive motor is supported within the confines of said belt and wherein said suction means includes a fan rotatable with said motor shaft and disposed within said side wall.

7. A construction as defined in claim 1 which includes discharge passage means in said side wall and cover, a detachable dust collecting means communicated with said discharge passage means, said suction means being operable to deliver dust from said dust removal passage means to said discharge passage means and then to said dust collecting means.

8. A construction as defined in claim 7 wherein said dust collecting means includes a dust bag having an inlet spout, said discharge passage means including an opening in said cover shaped complementary to said spout, and cooperable detent means on said spout and in said opening to detachably retain said bag on said device.

9. A construction as defined in claim 7 wherein said cover and side wall are formed with engaging surfaces spaced inwardly from the outer edge of said cover defining said enclosure, said suction means including a rotatable fan disposed within said housing side wall, first opening means in said side wall adjacent said fan and communicating the suction side of the latter with said dust collecting passage means, said discharge passage means being communicated with the blower side of said fan, whereby dust is drawn along said dust collecting passage means, through said first opening means and then to said dust collecting means by way of said discharge passage means.

10. A construction as defined in claim 7 wherein said discharge passage means includes communicated openings in said side wall and cover, said side wall and cover having cooperable, engageable surfaces surrounding said openings, said suction means including a rotatable fan disposed Within said side wall and having a blower portion to direct the collected dust away from said fan, said discharge passage opening in said side wall being communicated with said blower portion of said fan.

11. A construction as defined in claim 1 which includes handle means fixed to said housing and having a portion adjacent the rearward end of said belt working run, said handle portion having an inlet opening facing said 'belt, said cover having a portion overlaying said handle portion, said dust removing passage means being communicated with said inlet opening.

12. A construction as defined in claim 11 wherein said inlet opening extends transversely of said belt run and is opening to one side of said handle means, said cover overlaying said open side of said inlet opening.

13. A construction as defined in claim 11 wherein said handle means includes detachable, handle and handle cover portions secured together along a plane extending in the direction of said belt working run, said inlet opening extending transversely of said belt run and being formed in said handle and handle cover portions.

14. A portable sanding, polishing or burnishing device comprising a housing having a side wall, a drive motor on said housing, drive and idler pulley means on said housing and disposed to the inside of said side wall, said drive pulley means and said drive motor each having rotatable shafts extending to the outside of said housing side wall, transmission means to the outside of said side wall and interconnecting said shafts, cover means for said transmission means detachably secured to said side wall, an endless belt entrained over said drive and idler pulley means and having a longitudinal working run, means on said housing adjacent the rearward end of said belt working run defining an inlet opening, said inlet opening extending transversely of said working run and to the one side of said housig, said cover overlaying said inlet opening at said housing one side and having means associated therewith blocking passage of material out of said inlet opening, said cover being adapted, when said blocking means is omitted therefrom, to permit free passage of material out of said inlet opening, suction means on said housing dust removing passage means formed between said housing side Wall and said cover, and outside said transmission, interconnecting said suction means and said inlet opening when said blocking means is omitted, whereby dust formed during use of said device may be withdrawn through said inlet opening and said passage means.

15. A construction as defined in claim 14 wherein said cover has an inlet pocket communicated with said inlet opening, said passage means being formed by engaging surfaces on said cover and side Wall, and wherein said blocking means includes wall means on said cover adjacent said pocket and cooperable with a surface on said side wall whereby to prevent passage of material from said inlet opening, said suction means adapted to draw dust from said inlet opening into said inlet pocket and through said passage means when said rib means is omitted.

.16. A construction as defined in claim 14 wherein said cover is molded and of one piece construction and is adapted to be formed, using a single basic die, both with and without said blocking means.

17. A construction as defined in claim 15 wherein said blocking Wall is integral with said cover, said cover being adapted .to be molded, using a single basic die, both with and without said blocking wall.

18. A construction as defined in claim 14 wherein said cover is provided with a discharge opening therein communicating said suction means and dust bag.

19. A construction as defined in claim 18 wherein said cover is adapted to be molded both with and without said discharge opening and using a single basic die.

References Cited UNITED STATES PATENTS 3,049,842 8/1962 Morschel 5 l273X 2,280,867 4/1942 Swan 5'1-170.4 3,391,499 7/1968 Batson 51 '170.4 1,969,318 8/1934 Myers 51l70.4 2,654,190 10/ 1953 Mitchell 51-170.4

JAMES L. JONES, 111., Primary Examiner US. Cl. X.R.