US3119208A

US3119208A - Abrasive disc units

Info

Publication number: US3119208A
Application number: US212617A
Authority: US
Inventors: Henry L Gianatasio
Original assignee: Pres-On Abrasives Inc
Current assignee: Pres-On Abrasives Inc
Priority date: 1962-07-26
Filing date: 1962-07-26
Publication date: 1964-01-28
Anticipated expiration: 1981-01-28

Description

Jan. 28, 1964 H. l.. slANATAslo ABRASIVE DISC UNITS Filed July 26, 1962 INVENTOR. HENRY L. GmNATASlo ited States Patent @ddee lld Patented Jan. 28, 1964 3,119,263 ABRASEJE DESC UNITS Henry L. Gianatasio, @als Park, lil., assigner to lires-n Abrasives, lne., Addison, lll., a corporation of Iliinois Filed July 26, 1962, Ser. No. 212,617 2 Claims. (Cl. 51-195) This invention relatesy to abrasive disc units for abrading tools.

More speciiically this invention relates to an abrasive control disc unit which -is adapted to be mounted on a rotatable arbor or shaft which is adapted to be attached to the chuck of a portable electric hand drill, or other source of pov/er, for rotating lthe unit.

One of the problems experienced in the use of prior abrasive coated disc units, of the character referred to above,` has been the fact that the rapid rotation of the abrasive coated disc units in contact with the work, and the pressure exerted thereon, as an incident to the operation, and the heat of friction developed therein, has tended to cause the abrasive coated disc to disintegrate under the heat and pressure incidental to the use thereof, particularly when it is necessary to press the abrasive coated disc into contact with a curved surface of the work, vas is irequently necessary in using such abrading tools on metal castings, and the like.

Accordingly, .an object of the invention is to provide a new `and improved `abrasive coated disc unit which in use overcomes the above-mentioned and other difficulties experienced in the use of prior abrasive coated disc units of `a comparable character.

Another object of the invention is to provide a new and improved abrasive coated disc unit embodying a flexible abrasive coated disc of paper, cloth, or the like, lhavin-g a flexible resinous backing ii-lrn thereon which imparts greater liexibility and greater heat resistance and longer working or useful life to the new abrasive coated disc unit.

Another object of the invention is to p-rovide a new and improved abrasive coated disc unit including `a ilexible abrasive coated disc of paper, cloth or like material, having a primary flexible resinous backing film thereon and which is :co-extensive with the back snrface of the abrasive coated disc and a second and auxiliary reinforcing film of smaller diameter than the primary reinforcing )backing film on the rear surface of the said abrasive coated disc and between the latter and the primary iiex- -ible ii-lm for imparting additional strength and resistance to tearing and rupturing of the abrasive coated disc unit, particularly in the area thereof which is subjected to the greatest tendency to tear and rupture, namely, the area adjacent to the threaded ferrule or rivet to which the abr-asive coated disc unit is attached.

Other and fur-ther objects of the present invention will be apparent from the following description and claims and are illustrated in the accompanying drawing, which by Way of illustration, shows a preferred embodiment of the present invention 'and the principles thereof and what l now consider to be the best mode in which I have contemplated applying these principles. `Other principles may be used and structural changes may be made as desired by those skilled in the art Without departing from the present invention.

in the drawing:

FIG. 1 is an elevational View, partly in section, of an abralding ftool embodying the nelw abrasive coated disc unit;

FIG. 2 is an enlarged sectional View on line Z-Z in FIG. l;

FlG. 3 is an exploded perspective view showing the parts embodied in the new abrasive coated disc unit; and

FIG. 4 is an enlarged fragmentary sectional view of the area shown in FIG. 2 showing the manner in which the :abrasive coated disc and the primary resinous backing lm and the secondary or auxiliary backing iilm are attached to the threaded ferr-nie or rive-t which is ernbodied in the new abrasive-coated disc unit.

A preferred embodiment of the new abrasive-coated .disc unit is illustrated in the drawing, wherein it is gen;- erally indicated at 1i), and is shown as being used with and as a part of an abrading -tool which comprises a relatively small cylindrical metal shaft or arbor 11 having an enlarged ruibber head or mandrel 12 mounted thereon at one end thereof, the mandrel 12 being substantially larger in diameter than the shaft v11, and the shaft 11 being designed to be inserted into the chuck of a portable electric hand drill, or lite source of power, as is well understood in the art.

The rubber head or mandrel 12 has an enlarged annular flange portion i3l at its -forward end and this ilan-ged portion 13 forms or provides a cylindrical cup or cavity 14 which is open at its forward end, for a reason which will be pointed out presently.

The shaft 11 has a reduced screw threaded front end portion 1S which is arranged centrally within the cup or cavity 14 provided by the annular iiange 13 on the rubber cup or mandrel .12. The threaded vfront end portion 15 of the shaft 11 is adapted to be received in the threaded central base 16 of a ferm-le or rivet 17 which is provided at its front end with -iiexible deformable clamping iianges 18 `which are arranged radially therearound. As will be seen presently, the threaded ferrule or rivet 17 provides 'means for detachably atta-ching the new abrasive-coated disc unit 1@ to the parts 1-1-15-12 of an abrading tool.

The new abrasive-coated disc unit 11d includes a primary and disc-shaped flexible, resinous and relatively thin `abrasive-coated disc 19, which may be made of suitable material, such as paper, cloth, or the like, and which has an abrasive coating 2d on its face or front surface.

In the practice of the present invention, I provide a primary thin, disc-shaped, flexible, resinous lilrn 21 of iiexible polyester resinous material, such as Mylar (Du Pont), or equivalent flexible resinous material, which is co-extensive with the entire rear or back surface of the abrasivecoated disc 19-20, and this primary thin, flexible, resinous iilrn 21 is preferably in the order of about 0.003 inch thick, and is, heat-sealed or otherwise integrally bonded throughout its radially outer portion to the back or rear sunface of the abnasive-coated disc 19-20- The new abrasive-coated disc unit 1i? also includes a second and' auxiliary thin, plastic, resinous polyester film of disc-shaped form, of the same material (Mylar, Du Pont), or equivalent thin, iiexible material, which is preferably in the order of about 0.010 inch thick, but is substantially smaller in diameter than the abrasive-coated disc 1-9-20 and the primary, thin, iiexible resinous backing 21. This second or auxiliary flexible backing film 22 is disposed between the rear suriace of tlhe abrasive-coated disc .19 and the front sunface of the primary, thin, flexible, resinous backing iilm 21 and i-s also heatsealed or otherwise integrally bonded to the back or rear surface of the abrasive-coated disc 19, and the radially inner port-ion of the primary, thin, liexible, resinous back- 4ing film 21 is heat-sealed or otherwise integnally bonded to the rear surface of the secondary or auxiliary thin, flexible, resinous backing iilm 22.

In assembling the new abrasive disc uni-t a centrally arranged aperture Z5 is provided in the auxiliary iiexible resinous backing disc Z2 and a centrally arranged aperture 26 is provided in the primary, thin, resinous backing iillm 21, so that an annular marginal edge portion 24 of the second or auxiliary backing film 22 surrounds the central aperture 2.5I therein, and an annular manginal edge portion 23 in the primary resinous backing lilm 21 surrounds the central aperture 26 therein (FIGS. 3 and 4).

In assembling the parts of the new abrasive coated disc unit 10, the primary resinous backing film 19 and the auxiliary backing film 22 are cut from stock to suitable size and disc-shaped form with the

apertures

25 and 26, respectively, formed centrally therein. The flanged front end portion 18 of the thereaded ferrule or rivet 17 is then inserted through the central aperture 26 in the primary backing film 21 and through the central aperture 25 in the auxiliary flexible resinous backing film 22. The clamping flanges 118 on the ferrule or rivet 17 are then peened or deformed radially outwardly into engagement with the adjacent annular marginal edge portions 24 of the auxiliary flexible resinous backing film 22 so as to clamp the annular .marginal edge portions 24 land 23 of the flexible

resinous backing films

22 and 21 respectively, between the front face 27 of the body of the ferrule or rivet 17 and the clamping flanges 18 thereon (FIG. 4).

The thus assembled abrasive coated disc unit may then be detachably attached to the arbor or shaft 11 by threading the threaded front end portion of the shaft 11 into the threaded central lbore 16 in the ferrule or rivet 17.

It has been found that the primary disc-shaped flexible resinous backing film 21 on the back or rear surface of the abrasive coated disc 19-20 and the intermediate auxiliary flexible disc-shaped resinous backing film or washer 22 which is arranged between rear surface of the abrasive coated disc 19-20 `and the front Isurface of the primary flexible, resinous backing lrn 21 and around the ferrule or rivet 17, 'gives the new abrasive coated disc unit 1) greater flexibility and greater heat resistance, and longer working or useful life while, at the same time, providing greater resistance to tearing and rupturing of the abrasive coated disc 19-20 in use, 'and particularly in the area thereof which is subjected to the greatest tendency toward tearing and rupturing, namely, the area adjacent to the ferrule or rivet 17.

It will thus be seen from the foregoing description, considered in conjunction with the accompanying draiwing that, ythe present invention provides a new and improved abnasive coated disc unit having the desirable advantages and characteristics and accomplishing its intended objects including those hereinbefore pointed out and others which are inherent in the invention.

I claim:

1. An abrasive-coated disc unit for attachment to the shaft of a power driven rotary abi-lading tool comprising `a flexible abrasive-coated disc having `an uninterrupted front surface entirely covered with an abrasive coating, a second and auxiliary thin flexible resinous backing disc having a central aperture therein, said second and auxiliary thin flexible resinous backing disc being attached ccntrally to the rear surface of the said ilcxible abrasivecoated disc and being substantally smaller than said abrasive-coated disc, la flexible resinous backing lilm having a central aperture therein and attached to the second and auxiliary thin flexible resinous backing disc, and means directly attached to the said second and smaller auxiliary thin backing disc and to the said flexible resinous backing film adjacent the said central apertures therein for detachably attaching the said abrasive-coated disc unit to the shaft of a rotary power driven abrading tool.

2. An abrasive-coated disc unit as defined in claim l-iin which the said means for detachably attaching the said abrasive-coated disc unit to the shaft of a rotary power driven abrading tool is in the form of ia ferrule or rivet having a centrally arranged threaded bore therein for the reception of the threaded end portion of the said shaft of an abrading tool, and in which the said ferrule or rivet has a front end portion provided with a series of radially arranged clamping flanges extending radially outwardly from the said centrally arranged threaded bore in the said ferrule or rivet and into engagement with the marginal edge portions of the said centra-l :aperture in said second and 'auxiliary flexible resinous backing disc and binding the marginal edge portions of the said second or auxiliary flexible resinous backing disc and the marginal edge portions defining tlle `said centrally arranged aperture in said flexible resinous backing film between the said clamping flanges .and the body of the said fer-rule or rivet.

References Cited in the file of this patent UNITED STATES PATENTS 2,320,139 Kirchner May 25, 1943 2,520,763' Goepfer-t et al Aug. 29, 195() 2,567,782 Rhees Sept. 1l, 1951 2,996,851 Gianatasio Aug. 22, 1961

Claims

1. AN ABRASIVE-CAOTED DISC UNIT FOR ATTACHMENT TO THE SHAFT OF A POWER DRIVEN ROTARY ABRADING TOOL COMPRISING A FLEXIBLE ABRASIVE-COATED DISC HAVING AN UNINTERRUPTED FRONT SURFACE ENTIRELY COVERED WITH AN ABRASIVE COATING, A SECOND AND AUXILIARY THIN FLEXIBLE RESINOUS BACKING DISC HAVING A CENTRAL APERTURE THEREIN, SAID SECOND AND AUXILIARY THIN FLEXIBLE RESINOUS BAKCING DISC BEING ATTACHED CENTRALLY TO THE REAR SURFACE OF THE SAID FLEXIBLE ABRASIVECOATED DISC AND BEING SUBSTANTIALLY SMALLER THAN SAID ABRASIVE-COATED DISC, A FLEXIBLE RESINOUS BACKING FILM HAVING A CENTRAL APERTURE THEREIN AND ATTACHED TO THE SECOND AND AUXILIARY THIN FLESIBLE RESINOUS BACKING DISC, AND MEANS DIRECTLY ATTACHED TO THE SAID SECOND AND SMALLER AUXILIARY THIN BAKCING DISC AND TO THE SAID FLEXIBLE RESINOUS BACKING FILM ADJACENT THE SAID CENTRAL APERTURES THEREIN FOR DETACHABLY ATTACHING THE SAID ABRASIVE-COATED DISC UNIT TO THE SHAFT OF A ROTARY POWER DRIVEN ABRADING TOOL.