US2505680A - Pneumatic sanding wheel - Google Patents

Description

April 1950 A. w. MALL 2,505,68fl

PNEUMATIC SANDING WHEEL Filed March 1, 1947 2 Sheets-Sheet 1 prfl 25, 1950 A. w. MALL 2,505,530

PNEUMATIC SANDING Filed March 1, 1947 2 Sheets-Sheet 2 a LR INVENTOR.

Patente Apr. 25, 1950 lTED STATES ATENT ()FFICE PNEUMATIC SANDING WHEEL Arthur W. Mall, Flossmoor, 11]., assignor to Mall Tool Company, Chicago, 111., a corporation of Illinois 2 Claims.

The present invention relates to a wheel that is provided with an air cushioned tread portion. The invention is primarily concerned with sanding wheels wherein a ring or band of an abrasive such as sandpaper, or the like, is mounted on the peripheral or tread portion of the wheel. This tread portion is backed up over substantially its entire area by an air chamber so as to give resiliency to the sanding surfaces of the wheel.

Among the principal objects of the present invention it is intended to provide a relatively simple and inexpensive Wheel of this sort that is made up of a relatively small number of parts that are easily assembled to form a strong and sturdy device. During use of a sanding wheel the wheel is caused to rotate at a relatively high velocity and the article to be sanded is applied against the sanding surface of the wheel. Due to the friction between the sanding surface of the wheel and the article applied thereto there is a constant tendency for the bands forming the surface of the wheel to creep or move circumferentially about the wheel. This movement is prevented in the device forming the subject matter of the present invention in a manner to be described hereinafter. The air cushioning for the wheel periphery is provided without the use of an inner tube and the resulting structure is readily adapted for large scale production methods.

The foregoin constitute some of the principal objects and advantages of the present invention, others of which will become apparent from the following description and the drawings, in which Fig. l is a side elevational View of the sanding wheel forming the subject matter of the present invention;

Fig. 2 is a transverse sectional view through the wheel taken along the line 22 of Fig. 1;

Fig. 3 is a vertical sectional view through the wheel, the view being taken on the line 3-3 of Fig. 2; and

Fig. 4 is a fragmentary transverse sectional view through the wheel, the view bein taken on the line 4- of Fig. 1.

For purposes of illustration a single embodiment of the present invention will be described herein, though it is recognized that modifications will occur to those skilled in the art and it is intended that such modifications may be made Without departing from the scope of the invention.

Referring to the drawings the device forming the subject matter of the present invention comprises a wheel generally indicated at I10 (Fig. 2) that includes a hub portion II, a web I2 and a rim 13. The hub portion H is apertured at M to receive a shaft.

As shown in Figs. 2 and 4 the rim I3 is substantially symmetrically disposed with respect to the web 12 and provides a pair of outwardly extending annular flanges I5, each provided with an underneath locking face It. A passage I8 (see Figs. 2, 3 and 4) extends in a radial direction through the rim [3 and part way through the web l2. An air valve member 19 is threaded into an aperture 20 in the web portion l2 and this aperture 29 communicates with the radial passage I8. The valve member 19 may be a conventional valve member of the type employed in automobile tires, through which air is inserted for inflatin the tires. A removable cap 2| is provided on the open end of the valve member [9.

Mounted over the rim I3 is a flexible band 22 of rubber or like mate-rial that can be inflated with air. This band 22 is adapted to slip over the rim l3 and is provided with looking portions or heads 23 that are adapted to rest against the underneath face of the corresponding flange it. The edges of the flanges l5 are rounded to accommodate the band 22. A locking ring 28 is provided for each side of the wheel, each ring being adapted to clamp one side of the band 22 against the adjacent flange l5 of the rim 13. Each locking ring 24 is provided with a shoulder portion or head 25 that engages the corresponding lockin portion or head 23 of the band 22. Each locking ring 24 is further provided with a flange portion 26 and these flange portions 26 together with the web l2 of the wheel are apertured as at 21 to receive a plurality of bolts 28 that pass through the flanges 26 and the web I 2. The bolts 28 are provided with nuts 29 which draw the locking rings 24 tightly against the web l2 of the wheel [0. When the locking rings 24 are thus secured tightly to the web [2 of the wheel the band 22 is firmly clamped in place on the rim l3.

Mounted circumferentially about the wheel thus formed is a molded band 30 that has a width greater than the distance between the outermost edges of the assembled locking rings 24. Thus there is provided a wheel having a band 38 that provides a tread portion and by introducing air through the valve member and the passage it the band 22 becomes inflated with air that is disposed between the inner face of the band 22 and the outer face of the rim l3. By thus inflating the band 22 the molded band 30 is held in the flat poported on all sides. the vertically or radiall extending portions of sition shown in Figs. 2 and 4 or may in fact be very slightly arched outwardly with respect to the wheel II]. An abrasive band 3| may then be mounted over the molded band 30 and the wheel is then in condition for use as a sanding wheel, the abrasive band being mounted over the molded band before the band 22 is inflated. Pressure applied against the sanded surface of the wheel is thus resisted by the air cushioning behind th inflated band 22. The fact that the locking portions 23 are urged firmly against the underneath faces of the flanges 15 of rim l3 securely holds the band 22 on the rim [3 and prevents creeping or circumferential slipping of the band 22 about the wheel II]. It is to b noted that the underneath faces l6 of the flanges l are disposed in wedge-like relationship with respect to the locking rings 24 so that the locking portions 23 of the band 22 are in fact wedged between the looking rings 24 and the flanges I5 of rim l3. Thus, it will be seen that the inflatable band 22 is sup- It is supported laterally by V a sanding wheel it is recognized that it can also be provided with a polishing or bufling face in place of the sanding band and also there is provided a pneumatic wheel that i useful on small trucks, push carts, or other such small vehicles where an inflated wheel is desired.

The device herein described is uniformly balanced and a perfect seal for the air backing the band 22 is provided by virtue of the effective clamping arrangement. The wheel portion I0 may be die cast of aluminum, or the like, and thus the assembled device can be relatively light in weight.

I claim:

1. A pneumatic sanding drum comprising a wheel including a hub, a web extending around said hub and supported thereby, a rim extending around the web and supported thereby, said rim having flanges extending on each side of the web; an inflatable band fitted over said rim and an outer tread member mounted over said inflatable band for supporting a flexible abrasive band thereon, said band having beaded dges engaging the underside of the flanges On each side of said .web; a clamping ring for each side of the inflatableband, said rings being clamped to the web and having gripping portions extending laterally of; the web, said portions having a bead for engaging the corresponding bead on the inflatable i band so as to stretch said beaded edges towards the web and clamp the band around the rim when the clamping ring is tightened, thereby increasing the area of sealing contact of said band with said rim; each ring also having a portion extending radially from said lateral portion into contact with said tread and forming lateral support for ,said inflatable band, so that said band, when inflated, is clamped between said rim and said rings in a lateral direction, and between said rim and said tread in a, radial direction, said web having means for admitting air to the interior of the inflatable band to inflate the same.

2. A pneumatic sanding drum comprising a wheel including a hub, a web extending around said hub and supported thereby, a rim extending around the web and supported thereby, said rim having flanges extending on each side of the web, the side edges of each of the flanges being rounded and curving into the undersurface of each flange; an inflatable annular band fitted over said rim and extending around said curved flanges; an outer tread member mounted over said band for supporting thereon a flexible abrasive band; said inflatable band having beaded edges engaging, respectively, the underside of the flange on each side of said web; a clamping ring for each side of said inflatable band, said rings being clamped to the web and having a gripping portion extending laterally of the web, said portion having a bead for engaging the corresponding bead on the inflatable band so as to stretch said band around the curved edges of said rim when the clamping ring is tightened; said ring also having a portion extending radially from said lateral portion into contact with said tread, forming radial support for said tread and a lateral enclosure and support for said inflatable band, said band, when inflated, being supported laterally and radially in all directions, said web having means for admitting air to the interior of the inflatable band to inflate the same.

ARTHUR W. MALL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 472,287 Crooker Apr. 5, 1892 493,002 Webster Mar. 7, 1893 663,839 Woods Dec. 11, 1900 683,122 Knill Sept. 24, 1901 691,104 Blodgett Jan. 14, 1902 704,509 Cadman July 15, 1902 1,487,256 Mall Mar. 18, 1924

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