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Publication numberUS81260 A
Publication typeGrant
Publication dateAug 18, 1868
Publication numberUS 81260 A, US 81260A, US-A-81260, US81260 A, US81260A
InventorsS. W. Davis
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
US 81260 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)


Lettera Patent No. 81,260, dated August 1 8, 1868.


@the dgehule referat tu iu tlgeststters @that dat making gaat nf tkt sume.


Be it known that I, S. W. DAVIS, of Wilmington, in the county of New Castle,and State of Delaware, have invented a new and improved Bit-Brace, and I do hereby declare that the' following isa full, clear, and exact description thereof, which will enable those skilled in the art to make and use the same, reference being had t'o the accompanying drawings, forming part of this specificatiomiin whichv The drawing represents a side view of my improved bit-brace, with the bit-holding devices shown in section.

The object 'of thisinvention is to provide a simple and eicient bit-brace.

It consists of the combination of devices herein shown and described.

In the drawings, G is the ordinary bit-stock or brace. t p

My improvements relate to the manner of fastening the bit, for which purpose Iiemplhoy the case or'sleeve C, having a shoulder, c, which ts on the shank D, which is aixed to the partH ofthe brace, by means ofthe reduced end E of the' shank D, fitting in va hole in the part H,'and being keyed therein by a tapering pin or key,d. Y

The sleeve C slides freely on the shank D, against the tensionv of the spring e, coiled around the said shank, as shown. l

The front end of the shank is enlarged to t the bore of the sleeve, and is formed with a square cavity, to receive the square end A ofthe bit D.

I A pawl, a, is pivoted in the lateral mortise-shaped cavity, and opens into the end cavity ofthe shank, being so arranged that the pawl will 'catch in the notch of the b it, as shown, and prevent it from being withdrawn.

A stud or projection, b, from the pawl, passes loosely through a hole in the sleeve C, beingso arranged that when the said sleeve is pushed forward, theedge ofthe hole will encounter the projection b, and caus'e the end `of the pawl to be raised from the notch in the bit, so that the latter may be withdrawn.

The sleeve is held back against the part H by the tension ofthe coiled spring, and the opposite edge of the hole from that which acted to raise the pawl will act to depress the end ofthe pawl, and hold it in the notch.

Thus the coiled spring serves to bear the free end of the pawl in the notch when the brace is being used in boring.

I claim as new, and desire to secure by Letters Patent- The-combinationrof the shank D, and spring e coiled thereon, the movable sleeve C,'pawl a, and projection b, in a bit-stock, H vG, all substantially as shown and described, and for the purpose set forth. The above specification oi' my invention signed by me', this 26th day of June, 1868.

. s. wf DAvIs. Witnesses:

TuoMAs YOUNG, H. Monnow.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2639799 *Feb 1, 1950May 26, 1953 Pikal
US4900202 *Sep 8, 1988Feb 13, 1990Wienhold James LChuck assembly for tool bits
US5013194 *Feb 6, 1990May 7, 1991Wienhold James LChuck assembly for tool bits
US5417527 *Aug 12, 1994May 23, 1995Wienhold; James L.Quick change chuck assembly for tool bits
US6260857Jan 6, 2000Jul 17, 2001James L. WienholdQuick-change three-jaw drill chuck
US6457916Nov 15, 2000Oct 1, 2002Insty-Bit, Inc.Locking quick-change chuck assembly
US6561523Nov 16, 2000May 13, 2003James L. WienholdAutomatic tool-bit holder
US6588994May 15, 2001Jul 8, 2003James L. WienholdDrill bit tail
Cooperative ClassificationB23B31/02