US77219A

US77219A - Improvement in braces for bits

Info

Publication number: US77219A
Authority: US
Publication date: 1868-04-28
Anticipated expiration: 1885-04-28

Description

SLQRUNDLETT. BEACH FOR BITS.

m 77,219. Patented Apr. 28,' 1868.

,, Mtg

SAMUEL o. RUNDLETT, OF PORTLAND, MAINE.

* Letters Patent No. 17,219, dated April 28,1868.

IMPROVEMENT IN BRAGES FOR BITS.

ililn grinds-taunt is hi tips: with; than nut uniting put at ti e same TO'ALL WHOM'IT MAY CONCERN:

Be it known that I, SAMUEL C. Runnnnrr, of Portland, in the county of Cumberland, and State of Maine have invented a new and useful Improved Bit-Stock; andI hereby declare the following to be a full, clear, and exact description thereof,.which will enable others to make and use my inuentiom-reierenec being bad to the accompanying drawings, forming part of this specification, in whieh-- Figure 1 is 'a side sectional elevation. I

Figure 2, a plan of the slide or holder.

The operation of my invention is as follows: Through the head of the bit-stock, seen at a, fig. 1, into which the end, f, of the bit fits, I make aslot, b, somewhat wider than the cavity 'm, containing the head f of the borer. In this cavity is fitted a slide, a, which is shown in plan in fig. 2, in which there is a slot, d, 02' a proper size to admit the head of the bit. On the lower side of the slot, this slide'is chami'ered, as shown at a and a corresponding out made in the bit. At one extremity of the slide is a shoulder, 7:, to prevent it from slipping to i'itt into the stock, and at the other is a rod, 2', provided with a screw thread, and a thumb-screw, j. Around this red is arranged a spiral spring, k, which tends to keep the slide 0 in the stock, whether the bit or borer is in place or not.

When a tool is to be put into the bit-stock,- it is only necessary to slip it into the cavity m, when the end of the bit, coming against the chami'ered edge of the slide, will force it back till it strikes the out made in the hit-head, when, acted upon by the spiral spring k, it will be drawn forward and caught therein, securing the hour firmly in its place. When is is desired to change the instrument, by pressing the thumb on the thumbscrew j, it will be forced into the position shown by the dotted lines, fig. 1, when the tool may be readily drawn out, and the slide will resume its former place. The object of providing the endoi the rod 1' with the thumbscrew j is that the spring'may be readily tightened, it it should work loose, by a turn of the screw j. This will be found a great advantage; j

The peculiar points of my invention are its simplicity, rendering it less liable to get out of order, or wear out the arrangement of its parts allowing it to be readily got at, and-the accuracy with which the cut or shoulder may be made-in the bit or borer.

To fit a bit to this stock, the slide c is to be removed by taking oii the thumb-screw j and slipping back the slide, and the bit-he'ad is put in its place in the cavity m. Then a knife, or other marking-instrument, may be passed through they slot b, in which the slide c moves when in place, and the exact place upon which the chamfered edge e will strike when it is in the slot can be readily and accurately marked. This is of great practical value. g I

It will be seen that the slide 0 has no tendency to get loose, pressing, as it does, allthe time upon the borer, except when ptished outwardly by the hand on the thumb-plate. I

I do not claim securing the borer in' its place by a slotted slide, neither do I claim an automatic bit-brace; I do not claim the improvement of Horace Lettington, May 13, 1856, No. 14,876, where the bit is held by a rod or arbor, passing through the stock or hit ands portion of the socket, the arbor having a notch, as well as the shankof the bit, with a bolt pressing against the same.

I also disclaim the patent of L. L. Pollard, No. 32,890, July 23, 1861, where an anger is held in a. handle by a swinging pawl,-having a projection fitting into a notch on the auger-shank, which pawl is kept pressed against the shank by a thumb-piece, which is operated by a vertical spiral spring. This is diiierent from mine in that, in mine, the spiral operates directly upon a horizontal slotted slide, which encompasses the shank of the bit; but

What I do claim, and desire to secure by Letters Patent, is- The arrangement, in the horizontal slot'b, of the slide c, having'the shoulder h, slot d, edge a. rod 2, spiral is, and adjusting thumb-piece j, as and for the purposes set forth.

SAMUEL G. RUNDLETT.

Witnesses:

WM. H. Cmrroso, WM. FRANK Sssvsr.