US2746216A - Sanding attachment - Google Patents

Description

y 22, 1956 J. P. HOLLINGSWORTH 2,746,216

SANDING ATTACHMENT Filed May 12, 1953 Fig.

Fig. 3

Jean P. Hall/'ngsworfh INVENTOR.

BY wdWa/way 5m United States Patent Oflice 2,746,216 Patented May 22,1956

SANDING ATTACHMENT Jean P. Holliugsworth, Savannah, Ga.

Application May 12, 1953, SerialNo. 354,453

1 Claim. (Cl. 51-195) This invention relates in general for sanding attachments to be utilized in conjunction with portable sanding tools and pertains more particularly to an improved form of sanding member.

A primary object of this invention is to provide an improved form of sanding attachment which incorporates a sheet of flexible material of non-circular configuration whereby the circumferential portion of the attachment is formed in interrupted fashion, that is, the circumference of the member is formed with radial projections thereon.

Another object of this invention is to provide a sanding attachment constructed in accordance with a predetermined pattern to endow the same with the following characteristics 1. The attachment is self cleaning inasmuch as its circumferential portion intermittently engages against the surface which is to be sanded.

2. The attachment, by virtue of its interrupted circumferential formation, enables a user of the attachment to have visual access to a portion of the surface which is being sanded.

3. The standing member, being formed with radially projecting circumferential portions, will readily permit flexing of its circumferential portions to conform in shape with the object to be sanded.

The attachment will, by virtue of its interrupted abrading action, obviate the formation of grooves or scratches in the surface being sanded and will, in general, provide a more uniform sanding operation.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure 1 is a front elevation showing a portion of a vehicle with the novel sanding attachment utilized in conjunction therewith;

Figure 2 is a plan view of the sanding attachment and showing in dotted lines the manner of its sanding operations; and

Figure 3 is a transverse section taken substantially along the plane of section line 3-3 of Figure 2.

Referring now more particularly to Figure 1, reference numeral 19 indicates generally a portable grinder or sanding tool which is shown as of the electrically driven type and which includes a stub drive shaft 12 provided with the attaching washer and nut assembly 14, which is engageable within a central aperture 16 in the sanding attachment indicated generally by the reference character 18. Numeral 20 indicates generally the hood of a car while the reference character 22 indicates generally the fender thereadjacent and Figure 1 indicates the manner of utilizing the sanding attachment in conjunction with surfaces of both of these vehicle members.

Referring now more particularly to Figures 2 and 3,

2. reference numeral22 indicates the-main or central portion of the sanding-attachment within which the aperture 16 is providedandnumeral 24 indicatesthe peaked projections extending radially outwardly of this centralportion, such projections being formed by virtue of the fact that the sanding attachment is polygonal in configuration, although it is to beunderstoodthat other and different shapes than the hexagonal configuration shown may be utilized with advantage. The-material of which the sanding attachmentis. formed may be of any suitable commercial form. and. contemplates not only the use of a resilient backing plate provided with conventional sand paper secured to the outer surfaces thereof but also contemplates the use of the bonded type of abrasive material in which the abrasive is embedded throughout the entire body portion.

Referring now most particularly to Figure 2, it will be seen that the area which is sanded when the attachment is rotated will be circular in nature and will include those peripheral portions indicated generally by the reference numeral 26 and it will be appreciated that these portions form sectors of the circular area being sanded. Due to the rotation of the sanding attachment, an annular outer circumferential portion of the area sanded receives intermittent and sequential abrading actions by successive projection portions 24, this intermittent abrading action effecting the above described novel characteristics which enable the attachment to operate in the manner intended.

Considering the self-cleaning characteristic of the attachment, it will be noted that the radial projections extending from the main central portion of the sanding attachment will allow material engaged with the abrasive material to Work along the surface thereof until it has reached one of the edges 28 of the attachment and at this point such foreign material will be allowed to escape from the abrasive surface of the attachment. This will also tend to obviate the formation of deep scratches or grooves in the surface being sanded inasmuch as these grooves are normally formed by the abrasive material picking up particles torn from the metallic surface being sanded and carrying them along to gouge the surface of the metal. It will be readily appreciated that both of these characteristics are not present in the conventional form of circular sanding disks. Each individual path of movement on such disks defines a continuous circle which both prevents the above described cleaning operation and allows gouging of the metallic surface.

Furthermore, the over-all sanding action of the polygonal attachment shown will be far superior in its annular circumferential area than conventional circular sanding disks inasmuch as the intermittent abrading action by the radial projections will cancel out the minute scratches in the metallic surface of preceding projections, such not being the case in the use of circular disks inasmuch as these members will tend to establish a definite pattern of sanding operation forming a distinctive swirling lines of abrasion on the metallic surface.

Insofar as the visual aspect of the invention is concerned, it will be noted that the action of the projections 24 is much the same as is encountered in the case of rotating fan blades, that is, the surface being sanded beneath the projections is readily seen during the sanding operation so that the proper amount of abrading can be easily obtained.

In view of the foregoing, it will be readily appreciated that the preferred manner of utilizing the sanding attachment is to engage only its peripheral or circumferential portion against the surface to be sanded, the resultant sanding action by this particular portion of the attachment allowing the entire surface to be sanded to derive the benefits of the particular configuration of the attach- 3 1 ment as noted above. However, the device may be utilized in the manner shown in Figure 1 wherein a substantially circular area is sanded.

From the foregoing, the construction and operation of the device will be readily understood and further explanation is believed to be unnecessary. However, since numorons modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the appended claim.

What is claimed as new is as follows:

,A sanding tool comprising a rotary shaft and a disk of abrasive material having a center portion attached to said shaft for rotation of the disk about its axis by said shaft, said disk having a polygonal edge forming a plurality of straight peripheral edge portions and tips alternating with said edge portions, said edge portions and tips being of the same thickness, said disk from its center portion to said edge portions and tips being free and selfsupporting, said disk being flexible radially and axially for conforming to a concave surface to facilitate sanding by said edge portions and tips.

References Cited in the file of this patent UNITED STATES PATENTS 178,398 Barker June 6, 1876 1,156,958 Whitin Oct. 19, 1915 1,353,967 Lorenz Sept. 28, 1920 1,587,843 Koreneif June 8, 1926 1,938,520 Drapak Dec. 5, 1933 2,146,548 Mitschang et al. Feb. 7, 1939

Images