US2572327A

US2572327A - Spool-gripper carpet loom

Info

Publication number: US2572327A
Application number: US161832A
Authority: US
Inventors: Felton William
Original assignee: Crabtree & Son Ltd D
Current assignee: Crabtree & Son Ltd D; David Crabtree & Son Ltd
Priority date: 1949-08-17
Filing date: 1950-05-13
Publication date: 1951-10-23
Anticipated expiration: 1968-10-23

Description

W. FELTON SPOOL-GRIPPER CARPET LOOM Oct. 23., 1951 3 Sheets-Sheet 1 Filed May 13, 1950 I nventor Fulton William Attorney Oct. 23, 1951 w. FELTON SPOOL-GRIPPER CARPET LOOM 5 Sheets-Sheet 2 Filed May 13, 1950 Inventor Mil Ziam Fulton .B MMM W QEMlLMJdQ Attorney Oct. 23, 1951 w. FELTON 2,572,327

SPOOL-GRIPPER CARPET LOOM' Filed May 13, 1950 3 Sheets-Sheet 5 Inventor William Fulton Q By Attorney Patented Oct. 23, 1951 UNITED STATES PATENT OFFICE' 2,573,327 SPOOL-GRII'PER CARPET LOOM William Felton, Bradford, England, assignor to David Crabtree & Son Limited, Bradford, England, a British company Application May 13, 1950, Serial No. 161,832

In Great Britain August 17, 1949 1 Claim. (Cl. 139-7) This invention relates to spool-gripper carends through the comb whilst the spool frame is held momentarily in its active position by a holding device to provide the desired pile tufts which are then severed from the ends so as to leave sufiicient yarn projecting from the comb to enable the ends to be gripped on the next presentation of the said ends to the grippers.

In order to ensure that the correct length of pile tuft is severed and that a clear severance takes place, the ends must be kept in tension. Hitherto this tension was obtained by a continuously acting, spring loaded brake block pressing on the periphery of one flange of each spool. If the frictional resistance of the brake block to rotation of the spool is sufficiently strong to produce suflicient yarn tension to obtain the correct tuft length, a clean severance and the correct amount of projecting yarn for next production of tufts therefrom, the yarn gradually slips backwards through the comb, because it is elongated and tightened on the spool during the drawing thereof from the spool and thereafter gradually returns to its normal length and slackness on the spool, and therefore at the next presentation of the ends to the grippers there is in-' sufiicient yarn projecting to enable the grippers to grip it or the length of yarn engaged in "the grippers is reduced and therefore the tuft is shorter. As difierent ends stretch differently and are gripped with difierent degrees of tightness by the comb, this backward slipping takes place irregularly and gives rise to tuftless points and a ragged pile surface.

The object of the said invention is to ensure that the ends shall always be present in correct length of projection of their extremities from the comb when the grippers operate to grip them, whilst also ensuring that the yarn shall be in tension whilst it is being drawn through the comb and is having a tuft length cut off it.

A spool-gripper carpet loom'according to the said invention has a spool brake or brakes which exert a braking effect on the spools intermittently .and thus leave the spools free to rotate and thereby give off yarn to compensate for the yarn shrinkage in length and slackening'on the spools which occur between successive removals of tuft lengths from the spools.

The said spool brake or brakes may be operated by a mechanism which acts synchronously with the spool-frame holding device to apply the brakes for each period of operation of the holding device and release the brake or brakes at the end of each period of operation. v

The said spool brake or brakes may be mounted on a stationary part of the loom and act suc- 1 cessively on the spool or spools of each spool frame when it is in its active position.

The brake operating mechanism may be actuated by a link rod pivotally mounted on an. oscillatable arm forming part of the spool-frame,

'- holding device and connected by a second arm.

The brake or brakes preferably operate on one flange of each spool.

In addition to the intermittently acting brake or brakes, a constantlyacting brake may be provided on each spool frame for each spool, the resistance of the constant brakes to rotation of the spools being less than the resistance of the comb to slipping of the yarn therethrough and therefore not preventing rotation of the spools to compensate for the yarn shrinkage in length and slackening on the spool, but however being sufi'icient to prevent undesirable slackness of the yarn between the spools and the combs due to the weight of the yarn or vibration by preventing rotation of the spools by the weight of the yarn between the spools and the comb or by vibration in the intervals between the control of the spools by the intermittently acting brake or brakes.

I attain the said object by the mechanism illustrated in the accompanying drawings, wherein- Figure 1 is a fragmentary front elevation of a spool brake mechanism of a spool-gripper carpet loom;

Figure 2 is a front elevation of a portion of the mechanism illustrated in Figure 1 and is drawn to a larger scale; and

Figure 3 is a side view, regarded in the direction of the arrow 3, of the mechanism illustrated in Figure 1, and is drawn to the same scale as Figure 2.

Referring to the drawings, wherein some known parts are indicated in dot-and-dash lines, a construction is shown therein as applied by way of example to a spool-gripper. carpet loom in which each spool frame I has a spool 2 and a spool 3 rotatably mounted on it and is held temporarily arrested in its active position by a holding arm 4 which clamps it to a locating block 5 and is mounted on an operating shaft 6 actuated mechanically at the correct moments. A brake operating arm 4 is provided on the operating shaft 6 and has an elongated slot I and a pivotal stud 8 parallel with the operating shaft 6 is mounted adjustably along the slot I. An upwardly extending link rod 9 is connected to the brake operating arm 4' by an end piece I mounted on the pivot stud 8. The. upper end of the link rod 9 is connected to one end of an arm II by means of an end piece I2 and a pivot pin I3 engaging the end piece I2 and arm II and situated horizontally but at right angles to the pivot stud 8.

The arm II is secured on one end of a short shaft I4 mounted in a. stationary bearing I5 and having secured at its other end an arm I3 projecting upwardly and at right angles to the arm II, the shaft I4 being parallel with the pivot pin I3. The arm l6 has a link rod I1 connected to it pivotally by means of an end piece I8 on the rod and a pivot pin I9 which is parallel with the shaft I4.

The link rod II extends horizontally into the space between the sides of the spool-frame chains (not shown) and the lower chain wheels 3I provided to guide the said chains at the locality where the frames arrive in the active position.

A bell-crank lever 29 is mounted on a pivot stud 22 carried by a stationary part of theloom, the pivot stud 22 being parallel with the shaft I4. The lever 20 has an upwardly projecting arm 24 the upper end of which has a fork 25 open at the upper end and slidably engaged by the link rod H. The lever 2i} also has an arm 28 which is at an angle to the arm 24 and is also bent laterally to clear a shaft 33 on which the chain wheels 31 are mounted.

A bell-crank lever 2! is mounted on a pivot stud 23 carried by a stationary partrof the loom, the pivotstud 23, being parallel with the shaft IL The lever 2i has an upwardly projecting arm 25 the upper end of which has a fork 2l open, at the upper end and slidably engaged by the link rod II. The lever 2I alsohas an arm 29 which is at. an angle. to the arm 25 and is also bent laterally to clear the shaft 33.

The end of the arm 2.8 registers with a flange 32 of the spool 2 of each spool-frame I and the end of the arm 29 registers. with a flange 33 of the spool 3 of the same spool frame I when the respective spool frame I is in its active position. The end of the arm 28, has a brake block 34 adapted to be pressed against the periphery of the spool flange 32'. The. end of the arm29 has a brake block 35 adapted to be pressed against the periphery of the spool flange33.

For the arm 24 of the lever 29,. there is: on'the link rod H a fixed but adjustable collar 36 which acts to hold the brake block 34 clear and .a fixed but adjustable collar 33 which acts on the fork 4 tween the collar 38 and the fork 26 and presses the fork 26 towards the collar 36.

For the arm of the lever 2|, there is on the link rod I I a fixed but adjustable collar 31 which acts to hold the brake block 35 clear, and a fixed but adjustable collar 39 which acts on the fork 21 in reverse direction through a helical compression spring M on the rod I'l between the collar 39 and the fork 21 and presses the fork 21 towards the collar 37.

In operation, as the holding arm 4 is moved by its operating shaft 6 into the spool-frame clamping position, the link rod 9 is driven upwards by the brake operating arm 4' and rocks the shaft I4 by means of the arm II thereon. The shaft I4 rocks the arm I6 thereon and thereby pushes the link rod I! in the said reverse direction. The

collars

38, 39 on the rod I'I act through the compression springs 40, ill on the bell crank levers 20, 2| and rotate them until their

brake blocks

34, 35 are pressed against the spool rims 32 and 33 respectively with'pressure's pression spring 43 interposed between it and theare applied notwithstanding the presence of 26 in reverse direction through-ahelical compression spring 40 provided on the rod- I'I. be-

small irregularities in one spool position as compared with another or small discrepancies in the diameters of the spool flanges 32 and 33 or the inoperative brake block positions.

When the holding lever 4 is rocked by theoperating shaft 6 in reverse direction to release the spool frame I after yarn has been drawn and cut therefrom, the link rod 9 is pulled down by the brake operating lever 4' and the coliars 36, 31 onthe link rod H are thereby caused to pull the.

brake blocks

34 and 35 clear of the spool flanges 32 and 33 respectively The brake blocks 34 and 35 therefore hold the spools 2 and 3- strongly against rotation during each period of yarn withdrawal and cutting, but release the spools 2. and 3 immediately after that period and leave them free to rotate until the succeeding period of yarn withdrawal and cuttingoccurs. Therefore instead of the yarn being drawn between those periods backwards through the comb by shrinkage and slackening on the spool, the spools 2 and 3 rotate to let oif more yarn and therefore the positions of the ends are not disturbed at the comb between the said periods and the extremities of the. ends thereof are always available to the grippers and the length of the tuft pieces is substantially constant.

Light spring brakes (not shown) may-without detriment be provided on each frame to act on flanges of the spools in order to prevent the pull created by the Weight of the yarn or vibration from unwinding the yarn from the spools and thereby forming between the spools and the combs yarn loops liable to become entangled with each other. The spring brakes act continuously as heretofore but have insuiflcient braking action to prevent rotation of the spools'by the stronger pull created by yarnshrinkage and slackening ofthe coils of yarn on the spools after the tuft pieces: have been cut off and. the yarn tension created by thepull of. the; grippers: against the braking action of the intermittently acting brake blocks has therefore ceased.

I claim:

A spool-gripper carpet loom having a spoolbraking mechanism comprising an oscillatable arm, a link rod pivotally connected to the said oscillatable arm, a second arm pivotally connected to the link rod, an oscillatable shaft on which the second arm is fixed, a third arm fixed on the said shaft, 2, second rod pivotally connected to the third arm, an oscillatably mounted bell crank lever operated by the second rod, and a brake surface provided on the said bell crank lever for operation on successive spools of the loom whilst they are in the operative position.

WILLIAM FELTON.

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

UNITED STATES PATENTS