US1956638A - Mechanism for winding or taking down fabric as produced - Google Patents

Description

May 1, 1934- T. c. BRoMLl-:Y Er AL 1,956,638`

MECHANISM FOR WINDING OR TAKING DOWN FABRIC AS PRODUCED Filed June 15,'1951 e sheets-sheet 1 May 1,' 1934 T. c. BROMLEY Er AL 1,956-638 MECHANISM FOR WINDING' OR TAKING DOWN FABRIC AS PRODUCED Filed June 15, 1931 6 Sheets-Sheet 2 ,4 TTORNEYS May l, 1934. T. c. BROMLEY ET Al.

MECHANISM FOR WINDING OR TAKING DOWN FABRIC AS PRODUCED Filed June 15, 1931 6 Sheets-Sheet 3 F ig. 3. (cont.)

May l, 1934 T. c. BROMLEY ET AL 1,956,638

MECHANISM FOR WINDING OR TAKING' DOWN FABRIC AS PRODUCED Filed June 15, 1951 6 Sheets-Sheet 4 May l, A1934. T. c. BROMLEY ET AL MECHANISM FOR WINDING OR TAKING DOWN FABRIC AS PRODUCED Filed June l5. 1951 May 1, 1934. T. c. BRoMLEY Er Al.

MECHANISM FOR WINDING OR TAKING DOWN FABRIC AS PRODUCED Filed June l5. 1951 6 Sheets-Sheetl 6 Patented May 1, 1934 PATENT OFFICE MECHANISM FOR WINDING OR TAKING DOWN FABRIC AS PRODUCED Thomas Charles Bromley and Arthur Shortland,

Leicester, England, assignors to Mellor Bromley and Company Limited, Leicester, England, a

British company Application June 15, 1931, Serial No. 544,590 In Great Britain July 23, 1930 4 Claims. Y (Cl. Bti-153) 'Ihis invention relates to mechanism for Winding or taking down fabric as produced, and has reference more particularly to mechanism of this kind for application to circular knitting machines.

5 The invention is intended for application to both rib and plain machines of the rotary and of the stationary cylinder type.

For brevity herein the expression take down mechanism means mechanism of the type employing a pair of rollers by which the fabric is gripped and pulled down. The disadvantage with many take-down mechanisms is that the tension or pull on the fabric is seldom uniform, this being due, inter alia, to the fact that the take-down member or members do not rotate continuously, that is to say, there are times when the rotation of the said member or members is definitely interrupted. For instance, in mechanism o-f one type a slipping de- 2o vice is incorporated whereby the movement oi the take-down rollers is arrested when the tension on the fabric overcomes the power transmitted by the rollers. According to another known arrangement, the take-down rollers are driven by a worm and worm wheel or other gearing fitted with a clutch controlled by a series of gravity levers. The arrangement is such that the rollers rotate at a quicker rate than that at which the fabric is produced and thus climb up the fabric. The rotation of the rollers is arrested when they reach a predetermined point and commence feeding again when the gravity levers have fallen to a predetermined point. Thus at one period both rollers and levers are putting tension on the fabric, while at another period the levers only are tensioning the fabric, and it is found that the tension on the fabric varies considerably under these conditions. It will be understood from the preceding re- .40 marks that the main desideratum in a take-down mechanism is that a substantially constant or.

uniform pull should be exerted on the fabric, and

accordingly this invention has for its object the provision of a take-down mechanism of an improved and particularly efficient form whereby such desideratum can be achieved.

In itsbroadest aspect the present invention comprehends a take-down mechanism including driving means whereby the take-down members are driven continuously and positively, or substantially so, as long as fabric is being produced, and is or are thereby caused to exert a constant and even pull on the fabric throughout production. In other words the invention consists of a take-down mechanism wherein the fabric engaging members are adapted to have substantially continuous and positive action on the fabric while the latter is being produced so that the fabric is subjected to a constant and even tension during production.

An important feature of the invention resides in the provision of a continuously and positively acting take-down mechanism and means whereby the rate at which the take-down members are driven can be varied innitesimally within predetermined limits according to the rateat which fabric is to be produced, said means being entirely independent of and therefore unaffected by the fabric as it is being produced.

In further describing the invention reference will be made to the accompanying drawings wherein practical examples of the invention as applied to a circular knitting machine of the rotary cylinder type, are shown.

In the drawings Figure 1 is an elevation of the major part of the machine showing one example of the invention applied thereto.

Figure 2 is an enlarged View, partly in section, ofthe take-down rollers and the operating mech- 30 anism shown in Figure 1.

Figure 3 is a plan view of the arrangement shown in Figure 2.

Figure 4 is an enlarged end view of the rollers and ratchet mechanism for operating the same.

Figure 5 is a view similar to Figure 4 but shows a modified form of ratchet mechanism;

p and Figure 6 is a sectional plan view taken on line VI-VI of Figure 5.

According to that example of the invention illustrated in Figures 1 to 4, the take-down mechanism includes duplicate sets of pawl and ratchet mechanism comprising ratchet wheels 1, 1a respectively made fast on the spindles 2, 2a, of the 95 fabric gripping rollers 3, 3a at opposite ends, as shown in Figure 3. The ratchet wheels 1, la are rotated respectively by means of pawls 4, 4a, conveniently ten in each set, which are carried by arms 5, 5a freely mounted co-axially with the 100 respective ratchet wheels.

The gripping rollers 3, 3a are driven one from the other by pinions 3b or 3c, depending on which mechanism is operative, and together with the pawl and ratchet mechanisms, are carried by 105 brackets 6 attached to a plate 7 mounted to revolve in an annular part 8 carried by the legs 8a of the machine, said plate being driven from the main driving shaft 9 through bevel gears 10, 11,

a vertical shaft 12 and spur gears 13 and 14, the 110 latter being secured to the plate l in any suitable manner.

The arms 5, 5a are furnished respectively with pairs of rollers 15 for engagement with both sides of a stationary race such as a ring 16, which is carried pivotally by brackets 17 depending from the part 8 and is adjustable, as indicated in ,dot and dash lines in Figure l, by means of a handoperated screw 18 and a nut 19 carried by said ring. It will be understood that when the ring 16 is in the position represented by full lines in Figure 1 no movement is imparted to the arms 5, 5a when the latter are revolved round the ring, but when said ring -is inclined e. g. adjusted to the position shown by dot and dash lines maximum movement is imparted to the arms 5, 5a and consequently to the gripping rollers 3, 3a'. Since the ring is adjustable to any intermediate position, the rate at which the rollers are driven and consequently the feed imparted to the fabric per revolution of the machine can be varied innnitesimally between desired limits. The screw 18 is rotatably mounted on a pin 20 carried by the part 8, and is furnished with a knurled collar 21 for hand operation. A further collar 22 fast on the pin 20 holds the screw 18 in position on the pin.

In order to enable continuous rotary movement to be imparted to the gripping rollers in conjunction with feed variation as aforesaid therev is provided on each of the arms 5, 5a a number of pawls, e. g. ten, these pawls being spaced at intervals varied incrementally by a certain fraction, e. g. 1/10th or 1/20th of the pitch of the ratchet teeth. Thus, as the ring 5 is adjusted to vary the amount of rotary movement imparted to the gripping rollers, a different pawl will drop into driving engagement with the corresponding ratchet wheel, the particular spacing aforesaid ensuring that for practically any adjustment of the ring one or another of the pawls will bein a position immediately to drive the ratchet wheel when the arm is moved operatively by the ring.

As already alluded to a racking unit as Yabove described is provided on each of the spindles 2, 2a of the gripping rollers but at the opposite ends, the arrangement being such that while one of the arms is making an operative stroke the other is on the return or idle stroke. Thus.v the said rollers are never allowed to rest i. e. they are driven continuously.

The pawls 4, 4a are conveniently made out of circular discs 23 each recessed on one face 'as shown most clearly in Figures 2 and 4 so as to leave a projecting part to constitute the pawl. The discs are located in corresponding holes or recesses 24 in the arms 5, 5a and are held therein by a cover plate 25. Said discs are spring urged towards the ratchet teeth. n

The pivots of the ring 16 conveniently consist of screws 26 furnished with wing nuts 27 whereby the ring may be locked in position after adjustment.

According to a modication shown in Figures 5 and 6 we provide instead of the pawls and ratchet wheels aforesaid ratchet mechanisms each of which comprises an oscillatory arm l28 furnished at one end with a block 29 having formed therein recesses 29a the faces 38 of which are` slightly eccentric with respect to the pivotal axis of the arm, a plain disc or wheel 31 and rollers 32 located between the faces 30 and the periphery of the disc or wheel as shown in Figure 5. The arm or lever 28 is freely mounted co-axially with the disc or wheel 31, which latter is fast 'on the 'spindle 2 of one of the gripping rollers 3 of the takedown mechanism, the arrangement being the same at the opposite end of the spindle of the other winding roller, and the oscillatory arms are fitted with rollers 15a for engagement with the ring 16 for the purpose previously alluded to.

As already mentioned the cam faces 30 on the block 29 are slightly eccentric with respect to the pivotal axis of the arm 28, i. e. the centre of the disc or wheel 31, so that when the arm or lever 28 is moved by the ring 16, in the direction of the arrow in Figure 5, the rollers 32 are jammed or wedged between said faces and the opposing part o f the periphery of the disc or wheel 31, whereby the latter and the fabric gripping rllers are rotated.

As shown in Figure 6 the rollers are retained in position by a cover plate 33 screwed to the block 29. The block 29 is attached to a flange `34 on the arm or lever 28 by screws 35 so as to be readily removable for renewing purposes.

As will be observed the take-down rollers and the associated ratchet mechanisms revolve bodily synchronously with the needle cylinder and that both of the oscillatory arms are operated to drive the take-down rollers at every revolution of the machine i. e. the rotation imparted to the rollers is the same during each half revolution of the machine, so that said rollers are driven substantially continuously, and this in conjunction with appropriate adjustment of the ring 16 causes the rollers to act practically continuously with a constant and even pull on the fabric throughout production.

It will be understood from the foregoing description that in both-cases the take-down rollers are positively driven and practically always in motion while the machine is working, said rollers being rotated to the same extent according to the adjustment of the ring 16 for every revo 1 los lution of the machine. The tension on the fabric therefore is always the same. Further, as both rollers are directly driven in turn, i, e. one for one half revolution of the machine Vand vthe other for the other half revolution, the tension on both sides of the fabric is substantially the same, and there is no slip. In addition to this, as the rollers are drivenV from both ends, `the drive being taken by each roller in turn as aforesaid, the tension at each end of the fabric is j the same, and the possibility of the rollers slipping back is eliminated.

In order to facilitate the removal and insertion of the fabric from vor between the gripping so as to be relatively movable. For this purpose, and as shown particularly in Figure 4, one of the roller spindles 2 is Vcarried at -each end in a bearing block 36 adapted to -slide in a guideway 37 in the bracket V6. Each blockis spring controlled in one direction, and is'moved to separate the rollers by means of a plunger rod 38 having a bevelled or tapered-end V39 vfor co-operation with la corresponding part 40 on the block 36. Thusas the V1'od38 is moved downwards the block 36 and roller are moved outwardsor away from the other roller. For depressing the plunger rod we prefer to employ a cam or eccentric 41 on a horizontal Arod or shaft 42 for action upon the Yhead of said rod,

vmechanism of the Vforms Vherein described is `found'to function very `eiiiciently,and"accor` :l

'rollers 3, 3a, said rollers are preferably mounted ingly, to achieve the desideratum hereinbefore mentioned in an eminently satisfactory manner. Further considerably less tension on the fabric is required owing to the fact that the feed is always the same, thereby giving better loop formation without fear of cutting, throwing oil or loads up on the needles, and enabling very delicate yarns to be knitted. Another advantage is that the tension on the fabric or in other words the amount of rotation imparted to the rollers per revolution of the machine can be regulated without stopping the machine and Without the use of tools. A further advantage arising out of the improved arrangement is the entire absence of dangerous revolving parts between the bed plate of the machine and the take-down mechanism, so that a clear space is provided for observation and examination of the fabric as it is produced.

While for convenience the mechanisms hereinbefore described are referred to as take-down mechanisms it will be understood that the invention is not limited to use in any particular position in relation to the fabric producing means or instrumentalities e. g. below the same, as said mechanisms may be arranged in any suitable position for drawing-off or winding up the fabric as produced.

In the foregoing description of the construction of the machine the rotation of the roller has been described as positive and continuous. It is to be understood however, that the term continuous does not indicate that there is no cessation or intermittance whatever of rotary motion of the rollers, since such intermission may occur in the transfer of operating means from one roller to the other.

Such intermission or cessation however, is so slight and the transfer so nearly instantaneous that it is wholly negligible in its effect on the drawing down action of the rollers. The phrase substantially continuous herein used and embraced in the claims is therefore to be understood as indicating such a rotation alternately of the rollers as will produce the same effect as if their rotation were absolutely continuous and without any intervening pauses.

What we claim then is:-

1. In a circular knitting machine, power-driven fabric take-down mechanism comprising, in combination, a pair of rollers between which the fabric is gripped, means for positively and, substantially continuously, driving said rollers during the production of fabric, including ratchet mechanism and an angularly adjustable operating means between which and the ratchet mechanism there is relative rotation for operating the ratchet mechanism and means, operable manually, to effect the adjustment of the operating means to different angular positions, to vary the rate at which the rollers are driven and also adapted to hold the said means rigid in the desired position after adjustment.

2. In a circular knitting machine, powerdriven, takedown mechanism, comprising in combination, a pair of rollers between which the fabric is gripped, means for positively and, substantially continuously, driving said rollers during the production of the fabric, including ratchet mechanism and an angularly operating ring between which and the ratchet mechanism there is relative rotation for operating the ratchet mechanism, and means, operable manually, to Vary the inclination of the ring and consequently the rate at which the rollers are driven, and adapted to hold said ring rigidly in the desired position after adjustment.

3. In a circular knitting machine, powerdriven fabric take-down mechanism, comprising, in combination, a pair of rollers between which the fabric is gripped, means for driving said rollers positively and substantially continuously, during the production of the fabric, including ratchet mechanism having pawls spaced at intervals varied incremently by a fraction of the pitch of the teeth, and an angularly adjustable pivoted ring between which and the ratchet mechanism there is relative rotation for operating the ratchet mechanism and means operable manually for adjusting the ring to different angular positions and consequently regulating the speed of the rollers, and adapted to hold said ring rigidly in position after adjustment.

4. In a circular knitting machine, powerdriven fabric take-down mechanism, comprising, in combination, a pair of rollers between which the fabric is gripped, means for driving said rollers positively and substantially continuously during the production of fabric, including ratchet mechanism consisting of an oscillatory member formed with at least one face slightly eccentric with respect to the pivotal axis of the member, a disc, and an angularly adjustable pivoted ring between which and the ratchet mechanism there is relative rotation for operating the ratchet mechanism, and means, operable manually, to vary the inclination of the ring and consequently the rate at which the rollers are driven and adapted to hold the ring rigidly in the desired position after operation.

THOMAS CHARLES BROMLEY. ARTHUR SHORTLAND.

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