US1659687A

US1659687A - Dental-tool grinder

Info

Publication number: US1659687A
Application number: US554006A
Authority: US
Inventors: William G Hart
Original assignee: Individual
Current assignee: Individual
Priority date: 1922-04-17
Filing date: 1922-04-17
Publication date: 1928-02-21
Anticipated expiration: 1945-02-21

Description

Feb. 21, 1928. 1,659,681

W. G. HART DENTAL TOOL GRINDER 4 Filed April 17. 1922 INVENTOR.

JBZL. I

ATTORNEY-3.

Patented Feb. 21, 1928.

UNITED STATES 1 warms. mm,- or safaris-Ln, rumors.

Barman-r001. eniunnn. f

Application filed April 17,1922. Berlal 1T0. 554,006;

My invention relates to miniature grinders of the type used by dentists in sharpening by them .in the practice of their profession. I The grindingwheel which is formed as a' small stoneor from other abrasive material, is mounted upon the front end of a shaft which is journalled intermediate its ends in a: bracket so formed that it may be conveniently attached in position'upon any suitable base or support. The other end of 1 theshaft, projecting rearwardly from the bracket, is adapted to be clamped in the chuckon thelfree end of the flexible rotatingshaft whichforms apart ofthe equip ment of the dentists oilice. e i A tool rest issecured to the bracket atthe .front side ofthestone,'andtransversely to the axis thereof, inposition to oppose any .,longitudinal oraxial movement ofthe shaft carrying the stone, sothat thestone will rotate ina fixed plane during the grinding floperatiomandso tend to accurate well as.

uniform grinding of the instruments.

recess for the reception of the projecting forward end of the shaft, so that such tool rest may be located in immediate proximity to the stone. 7

The tool rest is provided with tool positioning guides, constituted as notches inclined at various angles with relation to the front face of the stone, so that the instruments mav be accurately held in position and supported near their points to permit correct sharpening. It has been found desirable to form the tool positioning guides upon both the upper and lower faces of the m tool rest. so as to meet the conditions im' posed when reversal of the attachment is required by any limitations of space, or for other reasons. b

Having in the foregoing outlined the purposes of my invention and its general nature,

I will now proceed with a specific description of the construction illustrated in the drawing, and then point out the novel fea- The face of the tooLrest next to the front sidepyof the stone,is bored out to form a as clamped upon the rear end. of the shaft 0 p upon which the grinding stone is mounted. thedehcately pointed instruments emplo ed Fig. 2 is a view in front elevation, showing the grinder in operative position. 7

Fig. 3 is a vertical sectional view on the line3-3,Fig. 2, but showing the shaft in elevation.

In the drawingthe numeral 10 indicates a bracket or frame formed by casting, press ing, or otherwise, and provided with means,

as a leg 11 and foot 12, for convenient attachment in any desired angular position upon a fixed or-stationary base or support.

I The front face of the-bracket is formed as a yoke, between the prongs 13 of which, space is provided for the accommodation of a small grinding wheel 14. the rear side of which lies in close proximity to the base plane 15 of the yoke. The thickness of the stone approximates the depth of the yoke.

The rearsideof the bracket is extended to form'a boss 16, which is bored transversely toform a bearing for a short, revoluble shaft 17.,which may rotate in a bushing shoulder against which rests 'awasher 19. A thread is out upon the projecting end of the reduced portion of the shaft, and a nut 20 is screwed thereon, to firmly clamp the grinding stone 14 against the washer, so that the saidstone will partakeof the rotation of the shaft 17 The bushing 18 should extend a short distance beyond the base 15 1 8,- setin the said bearing. The front end of "the shaft17 is reduced so as to provide s.

of the yoke, as shown in Figs. 1 and 3. so

that'the rotationof the parts will not be impeded by the frictional engagement of the washer with the bracket.

A tool rest 21, in the form of a bar, extends across the front face of the grinding stone, and is secured in position upon the bracket 10 by means of screws 22, which pass through the opposite ends of the bar, and are entered into threaded recesses in the prongs 13 of the oke, as shown in Fig. 1. The inner face of the bar in the line of the shaft, is provided with a circular recess 23, in which is received the front end of the shaft and the clamping nut thereon. The

purpose of this last described feature of construction is to enable the tool rest 21 to be positioned immediately adjacent the outer face of the grindingstone, so that the space to be bridged by that portion of the implethe most accurate results will be secured.

The tool rest 21 is speciallyformed so as to adapt it to the successful performance of its functions, the said tool rest 21 formed as a bar being provided upon its upper and lower sides with-a series of notches, some of which are indicated 24:, and which stand at various angles with relation to the vertical plane of the front face of the grinding wheel. The angular grinding or bevel of the point of the instrument may thus be effected by selectively positioning the instrument in that notch of the tool rest best adapted for the attainment of the purpose desired.

By providing notches 24, upon both sides of the bar constituting the tool rest, the device is rendered serviceable regardless of whether the foot 12 be attached at the left or at the right, or in other position with relation to the shaft 17. Additional holding guides 25, of different angles, may be formed upon the cross bar constituting the tool rest, to enlarge the range of the results flowing from the use of the device.

The end of the shaft 17 projecting rearwardly of the bracket will be reduced as at 26, to the diameter of the shanks of the drills forming part of the oflice equipment, so as to be readily entered into and clamped by the chuck 27 upon the free end of the flexible driving shaft 28.

In the construction which has been described, the grinding wheel 14 is held against movement axially of the shaft by which it is carried. By so maintaining the grinding wheel in a fixed plane of rotation, the grinding of the points of the instruments may be effected with greater precision.

Having thus described my invention, what I claim and desire to secure by Letters Patent of the United States, is:

A grinder for dental instruments comprising an attachable bracket recessed in its face to form a yoke for the reception of a grind-- in stone, a short shaft journalledin the said bracket and carrying at its front end a. stone arranged within the yoke, the rear end of the shaft projecting beyond the bracket to permit a driving connection to be made therewith, in combination with a tool rest secured to the front face of the bracket and provided with positioning means for determining the angularity of the points of the instruments with relation to the grinding stone, the said tool rest being recessed on its inner face for the reception of the front end of the shaft, whereby the tool rest maybe arranged in close proximity to the side face of the stone, and vibration of the instru ments during the grinding operation be avoided. i 7 v In testimony whereof, I have si ned my name at Fairfield, Il1inois,this 12t day of April, 1922.

wILLIAM e. Ham