US2570107A

US2570107A - Abrasive device

Info

Publication number: US2570107A
Application number: US135685A
Authority: US
Inventors: Harry U Gallagher
Original assignee: Individual
Current assignee: Individual
Priority date: 1949-12-29
Filing date: 1949-12-29
Publication date: 1951-10-02
Anticipated expiration: 1968-10-02

Description

Oct. 2, 1951 H. UQGALLAGHER ABRASIVE DEVICE Filed Dec. 29, 1949 far Patented Oct. 2, 1951 UNITED STATES PATENT OFFICE ABRASIVE DEVICE harry IT. Gallagher, Chicago, Ill.

Application December 29, 1949, Serial No. 135,685

claims. (01; 51-109) 1 This invention relates to an abrasive device, and-more particularly to a.--rotar ;abrasive device for use in preparing the edges. of instruments such asthose made of high-grade surgical steel,

as for example, those used by dentists andchiropodists.

A feature of this invention is to provide a new and improved abrasive'device of the character described. s p

Another feature is the provision of a rotary abrasive wheel having a workingsurface on its side to provide an effective diameter of Working surface larger than the diameter of the wheel itself.

Another feature is the provision of a device 'offjthe character described in which a side working surface on an abrasive wheel isaccessible for abradin'g the edge of an instrument from either side of the Working surface without interference from other parts of the wheel. 7

Another feature is the provision 'of a relatively small diameter abrasive wheel having a side working surface having an effective diameter much larger than that of the wheel, yet requiring lesspower to operate than astraightwheel of said effective diameter.

Another feature is that the side working surface provides a. greater wid-th of'working surface fora wheel of a given thickness and amount of abrasive material.

A further feature is theprovision ofrrotary abrasivewheels having'a working surface on the side of the wheel corresponding in radial" cross section to the cutting edge ofthe instrument toabeabraded.

Other features and advantages will be apparent from the description of a particular embodiment of the invention illustrated 'in the accompanying drawings, in which:

Fig. 1 is an 'elevatio'mpartly in "section, illustrating an embodiment of this invention;

Fig. 2 is a Fig. 1';

Fig. 3 is a vertical cross section throughwan abrasive wheel showing auvaried. form of working "surface'thereon; and

planvi'ew of the device illustrated in cal instrument such as used by dentist's or chiropodists, it is preferred that the diameter of the abrasive wheel be such that the cutting edge of the instrument is not too deeply hollow-ground. Ordinarily, a straight wheel, that is one inwhich the abrasive surface is around the periphery of the wheel generally normal to the sides ofthe wheel, is used to sharpen such instruments. It will be readily understood that'with a decrease in diameter of such a straight wheel an increase in the amount of hollow grinding of the cuttin ed'ge of the instrument results, as does also anincrease in the amount of tearing or gougingfof the edge because of the angle of attack of the Wheel to the edge being too great. Also with arelatively large diameter Wheel more power is required to operate the wheel than is necessary with amuch smaller diameter wheel. N

This invention has provided a solution to the above difiiculties wherein a relatively smalldiameter wheel may be used effectively and easily toabrade the instruments of the'pra'ctitioner' and the device may be placed in his oflice tahing'up relatively small space and utilizing: a relatively small amount of power in its operation. The term abrade or abrasive as herein used is to be construed as meaning any operation characterized by the act of a wearing by-friction; which may for example be any of the operations-commonlyn-called honing, sharpening, polishing, shapingQbuffi-ng; or the like.

The embodiment illustrated in Figs. l -and Z comprises generally-a housing 10 having a-bottomll supporting the housing and a top plate l2 enclosing at least a portion of the abrasive wheel all of relatively small size so that the dentist, chiropod-ist or other user may place the device at some convenient location where he may" use it at any time to abrade the cutting edges of his instruments. Mounted within the housing 10 isa slanting support member I3 carrying a motor 14 by brackets I5. The motor I4 is operativelyconnected to a shaft 16 upon which the abrasive wheel 20 is securely mounted and is preferablya relatively slow speed motor, that is havingpa speed of between and 200 revolutions perminute. The support member 13 is inclined within the housing [0 as will hereinaftermore lfully ap- .pear.

' diameter.

3 general known structures having an abrasive material bonded together to make a homogenous wheel or it may be of any base composition having an abrasive surface secured thereto, as a coating, disk, or the like. The wheel 2|] has a working surface 2| on its side adjacent the pe- .riphery 22 of the wheel and facing away from the plane of the wheel at approximately 10 degrees and the shaft I6 upon which the wheel is mounted is inclined within the housing at the same angle to the vertical so that the working surface 2| at the upper left hand portion of the wheel lies in a horizontal plane.

In providing a working surface on the side of the wheel and inclining the Wheel, an effective diameter at the abrading position will be much larger than the diameter of the wheel itself. As an example, a wheel having a diameter of approximately 6' inches and a working surface at 15 degrees to the plane of the wheel, would have at an abrading position an effective are of working surface corresponding to the arc of a straight wheel approximately 14 inches in diameter. This would correspond to havinga straight wheel of a diameter of about 14 inches and would require, as will be readily understood, a much greater power unit to operate than the 6 inch wheel utilizing the side working surface disclosed by this invention. A working surface on a 6 inch diameter wheel inclined at 10 degrees to the plane of the wheel would have a still larger effective Also a greater width of working surface-may be had with the working surface on the side of the wheel than with the same diameter of straight wheel using the same amount of material in the wheel.

top plate |2 provides a shield about the abrasive wheel protecting the fingers and hands of the operator. It will be noted that the top |2 has an opening 3| corresponding in configuration to an arcuate segment of the working surface 2| so that only a portion of the wheel projects above the level of the top l2. A ledge 32 beyond the outer periphery of the wheel, comprising an ex- 5';-

4 be sharpened by holding the handle of the blade over the ledge 32 of the top I2. In order to sharpen the other side of the blade the blade is turned over and the handle held over the center portion of the wheel so that the working surface may come into the cutting edge from the same direction as when sharpening the other side, the center depression in the wheel permitting a low enough mounting of the guard plate to avoid interference with the handle of the instrument. As will readily be seen from Figs. l and 2 the top |2 covers most of the wheel so that the hand of the operator would not be injured while holding the handle of the instrument generally over the center of thewheel in performing an abrading operation.

Many dentaland chiropody instruments have a curved cutting edge rather than a straight one. When it is desired to sharpen such an instrument, an abrasive wheel I29, such as illustrated in Fig. 3, may be provided with a working surface |2l generally at a small angle to the plane of the wheel and curved along a radial In mounting the abrasive device in the housing In as described above, the

in sharpening an instrument because the handle of the instrument may be held on either the left hand or right hand side of the wheel without interference with the wheel itself. When the working surface is on the side of the wheel as in the present invention, ordinarily the working surface may only be approached from outside of the wheel. In the present invention the working surface 2| may be approached from either "side thereof. For example, one side of the blade may cross section to correspond to the cutting edge of the instrument to be sharpened. The wheel I20 may be substituted for the wheel 20 in the device illustrated in Figs; 1 and 2 by simply removing the top l2 on the housing it, loosening the nut 35 which retains the wheel 20 on the shaft i6 and then placing the wheel I20 in position on the shaft. 1

In Fig. 4 another wheel 22|Jis illustrated having a working surface 22| with annular grooves 222 in the working surface. Such a wheel may be used for sharpening instruments having a hooked portion and instruments with rounded cutting edges such as nucleus knives used by chiropodists. Other wheels having various shaped working surfaces may be provided as desired. 7

From the foregoing it is believed that this invention provides a new and improved abrasive device in which a relatively small diameter abrasive wheel may be used to obtain a requisite larger diameter effective working surface and which requires substantially less power to operate than a straight wheel having said effective working diameter.

While I have herein described certain embodiments of my invention, it is apparent that some changes may be made by those skilled in the art. However, the invention is not to be limited by the foregoing description but rather to be construed broadly within the spirit and scope of the appended claims.

Iclaim: V 1, A rotary abrasive device comprising: a housing including a planar work supporting surface, said surface having an arcuate opening therein; a shaft supported adjacent said surface and at an angle of less than 30 degrees to a perpendicular to said surface; power means supported by said housing for rotating the shaft; an abrasive wheel mounted on the upper endof said shaft at substantially degrees .to-said' shaft; said wheelhaving anannular radial abrasive face surface positioned at an angle of less than 30 degrees to the'plane normal to the axis ofrotation of said wheel andthe same as the first mentioned angle, withthe surface facing away from said shaft anda'depressedportion in the center of said wheel adjacent said abrasive surface, said inclination. of said shaft being sufficient to rotate successive portions of the abrasive surface into 5 face and extending through said arcuate opening, with the work support surface masking the remainder of said abrasive surface and the corresponding portions of said depression.

2. A device of the character claimed in claim 1, 5 wherein the angle of the shaft with respect to the perpendicular and the angle of the abrasive face surface with respect to the plane normal to the axis of rotation of the wheel are both between 10 and 15 degrees, and both the same angle.

HARRY U. GALLAGHER.

REFERENCES CITED The following references are of record in the 15 file of this patent:

Number UNITED STATES PATENTS Name Date Howson Apr. 8, 1879 Barclay Feb. 12, 1884 Conradson Jan. 26, 1892 Brown Mar. 13, 1900 Connet June 29, 1909 Redden Feb. 3, 1914 Barnhart Oct. 25, 1921 Osterholm May 7, 1935 Weidrich Nov. 2, 1937 Myers Apr. 19, 1938 Benedict Mar. 19, 1940 Atkin Aug. 2, 1949