US1542328A - Let-back for loom take-ups - Google Patents

Description

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1 f w. H. WAKEFlEL D LET-BACK FOR LOOII nxz-urs Filed Oct. 4, 1923 5 b I I wumrfi m-w- "ingrotatesltlie take-up iroll in a steady for;

Patented June 16, 1925.

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a s qnusarrfs, ASS 'GN R T R MBTQN a Know sto u WORKS, or woia ons'rnn,nassacnusnrrs, acoarwganr qa or NAS T LET-BACK'FOB r f i hpplicatibn filed Qctober To all whom time comma,

Be known th t I, W LTER H. WAKE- FIE D, acitizen of the United Statespresid ing at Worcester, in the county or Worcester 1 and State of Massachusetts, have invented a new and useful Let-Back for Loom ilake- Ups, of which the following is a specification.

This invention relates tolet-bfack mechanismfor takemp motions" and an object of the invention is to relieve the filling stop motion of the" strain otdisconnecting e e-11p me hani m ro us d i e h n.

a fault in the filli' g occurs.

Take-up 'motions are ordinarily actuated y ome e ul r mar e Par or he 9 m nd e i e are: a c n ta t r int r te t motion means of which a trainlof gearr d'i t a h n a faultia e fi es occurs it is necessary for the weft to be withdrawn and unless the take-up roll is moved,

backwardly an amount to compensate the withdrawn weft, athin place will ap pe t thall etb ck,

motions are customarily: employed to, permit the take-up roll to have this retrograde o 1'? 9 se i s, ee sar btere 1 the roll can move back tO' dISQ O Ill'lQQlP gearingconnected therewith from the dr1'v-- in-g mechanism. In the"type' bidet-back motion to which present invention relates, the strain of disengaging the take-up motion from its drive has ordinarily been assumed by the filling stop 'motipn, but where the fabric is heavy found that the strain is so great that the stop motion cannotbe relied upon to eflect proper disengagement of the driving parts? In an application filed by Joseph Wilkinson June 18, 1923, Serial No. 645,968, there is shown a motion somewhat similar to thev let-back mechanism wherein the several,

parts may be made of relatively light material compared with the work to be done.

It is a further object of my invention to employ connections between the disengagmay; j; 4, 152 3. stun i 665,594,

ing mechanism and some adjacent fixed part of; the loom, whereby thefilling stop 'mo{ tion is called upon merely to position the connections, while the actual strain t' dis engaging the fixed part.

Vith these and other objects in view, which will appear as'the description pro ceeds, my inventionresides in the combination and arrangement of partshereinafter setforth and more particularly claimed In the drawings, wherein one form of my invention is shown, h

I Fig- 1 is a sideelevation of portions of loom having my invention applied thereto. Figs; 2 and 3 show certain parts illustrated in Fig. 1 in different positions.

Fig. 4- of Fig.1,and

Fig. 5r is vie-W- similar to Fig. {1, but

taken on line 5-5 of'Fig. l and showing motion shaft;- 7

Referring particularly to the drawings, there is shown a lool'n side 10 having a fill ing stop motion 11. provided with a fork 12 and tail 18flmovable. therewith, A lever la'pi-vote'd at 15 of"'the'loo1n"frame has *The crank shaft 23 has fixed thereon an eccentric 24 surrounded by an eccentric strap 25, by means of which a horizontal reciproeating motion is given feed pawl 26. R0- tatab y mounted on a fixed center, as at 27 is a ratchet Wheel 28, the teeth of which are successively engaged by pawl 26 and moved in a clockwise direction as viewed in Fig. 1 when the crank shaft 23 is rotating. A hold pawl 29 is pivoted to the frame'at 30 and serves to prevent retrograde movement of ratchet 28 when the pawl 26 is moving forwardly.

A stand 31 is secured to the loom side and has pivotally mounted thereon an arm 32' to the outward end of which is pivoted parts is transferred to the is a horizontal section on'line certain connections the filling a foot/L6 positioned for engagement with v let-back pawl 33 which latter is normally in.

contact with one of the teethof the ratchet 28, while the arm 32 is spaced from stop 34 located immediately in front of said arm. The matter thus far described is of the usual construction and no claim is made therefor.

My improvements consist of an arm 40 fastened to the shaft 20 as shown in Fig. 5 and from the rear end of which depends connector 41. A cam arm 42 is loosely mounted upon the shaft 20 between arm 40 and a collar 43 fastened to said shaft. For the purpose of raising cam arm 42 I provide a toggle joint, one member 44 of which is pivotally connected to a fixed stud 45 and the other member 46 of which is pivotally connected to the lower end of connector 41 as at 47 and also the cam arm 42 at 48. The cam arm 42 is normally in the position shown in'Fig. 1 with the toggle joint broken and is so positioned as to be out of thepath of the pawl 26 when the latter is in its foremost position.

When a fault in the filling occurs, arm 21 will move to the position shown in Fig. 2 and arm 40 will accordingly be raised, the result of which is to straighten the toggle. As this occurs the cam arm 42 is moved to the raised position shown in Fig; 2. The parts are so timed that the pawl 26 moves rearwardly. at the time that arm 19 moves forwardly, the resultof which is that hold pawl 29 is free to be raised from the ratchet wheel 28 when the toggle is straightened. For the purpose of raising pawl 29 a pin 49 is secured to cam arm 42 and passed under said holding pawl to raise the latter to the position shown in Fig. 2.

By referring to Fig. 1 it is seen that cam 17 is provided with a dwell, th purpose of which is to hold the arm 21 forwardly for an appreciable interval of time. Dur ing this interval of time, the pawl 26 is moved forwardly and a lateral extension 50 formed thereon is caused to ride upon the upper face of cam arm 42, the effect of this being to disengage the pawl 26 from ratchet wheel 28. When this takes place the tension of the cloth moves the ratchet wheel counterclockwise and the let-back pawl 33 moves forwardly until arm 32 is arrested in its motion by stop 34. The

parts will then assume the position shown in Fig. 3. After the filling fault has been corrected arm 21 and slide 22 are moved to their normal rearward position either by disengaging the tail 13 from the arm 19 or by turning the loom over until foot 16 leaves the dwell 47 on cam 17.

From the foregoing .it will be seen that the cam arm is raised to operative position with the driving pawl by means of connectors from the filling stop motion, but thatthe strain and pressure on said cam arm incident to the disengagement of the drive pawl and the ratchet wheel is transferred to some fixed part of the loom and not the filling stop motion.

Having described one form of my invention it will be apparent that changes and modifications may be made therein by those skilled in the art and I do not wish to be limited to the specific structures illustrated, but what I do claim is: 1. In a take-up for looms having a filling stop motion, a reciprocating take-up actuating pawl, a cam normally out of the path of the pawl, a toggle joint interposed between the cam and a fixed point on the loom, and connections between the stop motion and the toggle to move said cam into the path of the pawl when the stop motion operates.

2. In a take-up for looms having a filling stop motion, a reciprocating take-u actuating pawl, a cam normally out of the path of the pawl, a toggle joint interposed between the toggle joint and stop motion to straighten the toggle joint when the stop motion operates to move said cam in the path of the pawl, said connection resetting the toggle and moving the cam to inoperative position when the stop motion is restored to normal running position.

In testimony whereof I have hereunto affixed my signature.

WALTER H. WAKEFIELD.

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