US2605539A - Stock stop for automatic lathes - Google Patents

Description

'F iled Jan. 22, 1947 g- 5, 1952 4 G. E. cuT'rAT 2,605,539

. STOCK STOP FOR AUTOMATIC LATHES 3 Sheets-Sheet 1 v G. E. CUTTAT swocx STOP FOR AUTOMATIC LATHES Aug. 5, 1952 S'Sheets-Sheet 2 Filed Jan. 22, 1947 v I STOCK STOP FOR AUTOMATIC LATHES Filed J n.'22,j1947 i *5 s Sheets-Sheet-3 the length of-feedof the work,

Patented Aug. 5, 1952 f-2,e05,5-s-9= v lSTOCK STOP FOR AUTOMATICLATHES Geneva-,; Switzerland, asre De Machines Du Hau'tlthin, Ham-Elfin, Francega compamyof France Ap lication January 22, l|l47,1SerialNoT.723,596

In France November 23,1945

Georges Emile Cuttat, signor to Manufactu The present invention concerns the oscillatin thrust blocksusedin automatic lathes tolimit and, particularly, of the work bar. At the presenttime, these-oscillating thrust blocks are capable only of a rotary motion about their axle, in a plane perpendicular to the bar. This arrangement is not without its drawbacks as the friction exerted by the end of the bar on the thrust block, (the bar bein clamped in the headstock), offers a resistance which may be fairly considerable, to the motion of the thrust block.

In order to eliminate this drawback, an object of the present invention is an oscillatory thrustblock device receiving automatically from its controlling organ a slight longitudinal motion parallel to the bar, before the controlling organ imparts to the thrustblock its oscillating motion perpendicular to the bar.

One type of embodiment of an oscillating thrustblock device, in accordance with the invention will be described, hereinafter, by way of example and is represented on the appended drawings in which:

Figure 1 is a side elevation of the whole device; Figure 2 is an elevation at 90 to that of Figure Figure 3 is a modification of Figure 2 for the case where the drive is efiected by the main cam shaft instead of being eifected by the auxiliary shaft;

Figure 4 is a cross section, on an enlarged scale, of Figure l; and

Figures 5 to 9 are schematics, at 90 to Figure 4, showing the cooperation of the thrust block organ of the control lever with the stops of the thrust block ring.

It will be seen from Figure 1 that, to determine the extension of the work bar from headstock 2, an oscillating thrust block 3 is used, mounted on an axle 4 capable of turning inside a fixed part 6 of the frame (see also Figure 2). When bar I has been pushed against thrust block 3, and firmly clamped, the friction exerted between the bar and the thrust block opposes fairly strongly the motion of the latter to release the end of the bar. According to the present invention, it is proposed to eliminate this friction.

To this effect, (Figure 4), the axle 4 of the oscillating thrust block offers, at its rear end, a threaded part 1 on which is screwed the end of the controlling organ, either lever B, articulated to link 9, itself articulated to bell-crank lever connected through link l2 to a lever l3 capable of oscillating about an axle l4, and carrying a r ller z filazims. (01. 29-58) I 2-,"onauxiliary shaft l6.

2 engaged by-a cam [5, locked, in the case of Figure The drive can be effected, asshow-n on Figure 3, in a 7 does not have to be described especially, from the main cam shaft [1.

A return spring I8 connects bell crank lever l l to a fixed point of frame 6.

The axle 4 of the oscillating thrust block is associated, in rotation, by two fingers IS, with a ring 2|, constantly urged towards the left of Figure 4, by a spring washer 22 bearing against a lid 23 attached to frame 6. Ring 2| carries two stops (Figure 5), 24, 25 between which a thrust block organ 26 is engaged, associated with control lever 8. A spring 21 connects one point of control lever 8 to one of the steps '25 of ring 2|.

The operation of the device is as follows:

Suppose that we start from the position in which oscillating thrust block 3 is in contact with bar I. The roller of lever l3 moves on cam l5, which, through lever l and link 9 rotates control lever 8 while stretching return spring I8. Then,

' axle 4 of the oscillating thrust block is prevented from turning by the friction of thrust block 3 on bar I. The result is that control lever B is slightly unscrewed on threaded part 1 of axle 4. But spring 22, exerting its action through ring 2| pushes axle 4 towards the left until lever 8 bears against a shoulder of frame 6, (position represented on Figure 4). Meanwhile, thrust block organ 25 (Figures 5 and 6) has turned freely until contacting stop 25 .of ring 2!, (position shown on Figure 6). From that time on, control lever 8, continuing its rotation, drives stop 25 and, consequently ring 2|; the latter, inturn, rotates axle 4 and thrust block 3 rises, releasing bar The position of Figure 7 is then reached which corresponds to the position of the apex of cam l5. When this apex has been passed, it is return spring l8, which, upon extending, will cause the oscillating thrust block to move down, then displace it towards the right, so that the new bar introduced in the headstock can be applied against it. Lever 8 rises, (Figure 8) accompanied in its motion by stop 25, owing to the pull of spring I8, axle 4 therefore rotates, causing oscillating thrust block 3 to move down. Stop 24 then bears against frame 6. Then ring 2| is no longer driven and lever 8, continuing its upward motion, screws on threaded part 1, with the result of displacing axle 4 towards the right, (Figure 9) until it is in the required position. Bar I can then be pushed against oscillating thrust block 3 without any risk of the oscillating thrust block moving.

manner which What I claim is:

1. In a stock stop for an automatic lathe, an axle parallel to the direction of feed and rotatably and slidably mounted in a fixed part of the lathe, a stop mounted eccentrically on said axle, said axle having a threaded part, elastic means interposed between said axle and the fixed part of the lathe for moving said axle in the direction of feed, an internally threaded oscillating member mounted in the fixed part of the lathe, engaging the threaded part of said axle for imparting to said axle a first longitudinal limited releasing movement under the action of said elasticmeans when the rotation of said axle is prevented by the friction of the stock on the stop, and means provided on said oscillating control member adapted to actuate means associated with said axle to impart to said axle a rotating movement after the first longitudinal movement.

2. In a stock stop for an automatic lathe, an axle parallel to the direction of feed and rotatably and slidably mounted in a fixed part of the lathe, a stop mounted eccentrically on said axle, said axle having a threaded part, an internally threaded oscillating member mounted in the fixed part of the lathe concentrically with the axle at the rear of said axle and threadably connected therewith, a ring connected to said axle elastic means interposed between the fixed part of the lathe and said ring for moving said ring in the direction of the feed, two stops provided on the periphery of said ring, a stop provided on said oscillating control member between said two stops of the ring, and elastic means connecting one of the two stops of said ring with said oscillating control member.

'. GEORGES EMILE CUTTAT.

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

UNITED STATES PATENTS Stull June 17, 1941

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