US806594A - Spindle-lock for micrometer-gages, &c. - Google Patents

Description

110.8%,594. v 4 'PATENTEDDEG.5,1905.

' L. s. STARRETT.

- I SPINDLE LO GK FOR MICROMETER GAGES, 6w.

APPLICATION FILED maze, 1905.

7 tween its tubular end portions an annular' UNITED STATES 'LAROY S. STARRETT, ATHOL, MASSACHUSETTS, ASSIGNOR TO L. S. STARRETT COMPANY, OF ATHOL,

OF MASSACHUSETTS.

PATENT OFFICE.

MASSACHUSETTS, A. CORPORATION SPINDLE-LOCK FOR MIC-ROMETER-GAGES.-&o.

Specification of Letters Patent.

Patented. Dec. 5, 1905.

Application filed March 23, 1905. Serial no. 251,691.

To all whom it mag/concern.-

Be it known that I, LAROY S. STARRETT, of

Athol, in the county of Worcester and State of Massachusetts, haveiinvented certain new anduseful Improvements in Spindle-Locks for MicrometenGages, &c., of which the fol- "lowing is a specification.

The object of this invention is to provide at small cost a simple and most efiicient device for locking a rotatable shaft or spindle in its bearing, so as by a very slight rotary movement to hold the shaft or spindle in any given adjusted position.

My especial purpose is, as herein illustrated, to perfect the ordinary micrometer-caliper by furnishing it with my improved locking device.

My improvement consists in bushing firmly secured in the tool-head or bearing portion of a micrometer-body surrounding its rotatable spindle and having bespring-tongue integral with and nearly severed from said end portions in parallel transverse planes and nearly-or quite severed at one end in a longitudinal or axial plane and weakened to permit a slight yielding or spring action at that end of the tongue, said tongue having near such longitudinal plane of severance a flat-bottomed peripheral recess deepest at its radial inner end and decreasing thence outwardly, the plane of its bottom being preferably the half-chord of a short are and terminating abruptly, in combination with a minute bar or roller located longitudinally in said recess with its ends adjacent to the inner walls of the end portions of said bushing and with an actuating-ring fitting rotatably into a transverse slot in the tool-head and loosely around said annular tongue and the rollerin' closed in its recess.

In thedrawings, Figure 1 is a side elevation of a micrometer-caliper provided with my improvement. Fig. 2 is an enlarged longitudinal section through the tool-head and locking device. Figs. 3 and 4 are transverse sections taken, respectively, on lines 3 and4, Fig. 2. Fig. 5 is a side view, and Fig. 6 a distorted perspective, of the bushing detached.

. In Fig. 1, 10 represents the tool-head at one end of its curved body, 11 the fixed cylindrical shell projecting from the head, and 12 the rotatable sleeve surrounding said shell, both bea cylindrical ing accurately graduated in a manner well known in instruments of this class. The spindle 13 is secured at its inner end for rotation with said sleeve and has a threaded engagement within shell 11 of a pitch corresponding to the graduations on said shell. 1

- In applying my improved locking device to a rotatable shaft or caliper-spindle I form through the bearing portion or head 10 a transverse slot 14 perpendicular to the spindleaxis. ring 15, snugly fitting between the slot-walls and extending radiallyslightly beyondthe periphery of the bearing, or head, and I introduce axially into said bearing or head and through ring 15 a cylindrical bushing 16 of peculiar construction and secure it firmly within head 10, said ring being rotatable in. slot 14 around such bushing. Between; the end portions of bushing-16 and integral with Ithen place within said slot a milled.

it I form an annular spring-tongue 17 in the plane of but slightly narrower than ring 15 by sawing two deep parallel transverse slots 18, as best shown in Figs. 5 and 6, such slots nearly severing the bushing, as in Fig. 4:, which is a section inthe plane of one of these slots. Adeep longitudinal saw-cut, slot, or groove 19 at one end of slots 18 and a peripheral recess 20 adjacent thereto so weaken the ring-shaped tongue that at that point it may be pressed slightly inward into binding contact with the inclosed spindle, so as to prevent its rotation. The recess 20 (best shown in Fig. 6) has a fiat bottom and radial inner end wall extending thefull width of the tongue, said bottom preferably forming the half-chord of a short are and said recess diminishing in depth from such end wall and disappearing near slot 19.

,cess with a wedging action, which springs that part of the tongue inwardly and locks the spindle firmly. A similarly-limited-reverse movement of ring 15 instantly releases the grip upon the spindle.

I claim as my invention 1. The described locking device for a rotatable shaft or spindle, comprising abearing or tool-head formed with a deep transverse slot, a cylindrical bushing inserted axially and fixed in position in such bearing or head, bored to fit the inclosed shaft or spindle, and having between its rigid end portions and in the plane of said slot an annular springtongue integral with but nearlysevered from such end portions and formed with a peripheral recess deepest at its abrupt inner end, decreasing in depth outwardly therefrom in a plane flat bottom, in combination with a movable clampingpiece located longitudinally in said recess, its diameter being equal to the greatest depth thereof, and with an actuating-ring fitting rotatably in the tool-head slot and around the recessed tongue and inclosed piece substantially as set forth.

2. In a micrometer-gage the tool frame or head, the rotatable spindle and micrometer mechanism, a deep transverse slot in the toolripheral recess, deepest at its radial inner end and decreasing thence outwardly, its fiat bottom forming the half-chord of a short are, and a roller of a diameter equal only to the greatest depth of such recess held movably therein and operated by said actuating-ring, for the purpose set forth.

In testimony whereof I have aflixed my signature in presence of two witnesses.

LAROY S. STARRETT.

Witnesses:

FLORENCE E. Boron, FRANK E. TING.

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