US2101494A

US2101494A - Circular knitting machine

Info

Publication number: US2101494A
Authority: US
Publication date: 1937-12-07
Anticipated expiration: 1954-12-07

Description

Dec. 7, 1937. E, DEANS ET AL 2,101,494

CIRCULAR KNITTING MACHINE Filed March 4, 1936 3 Sheets-Sheet 1 I "I, l

Dec. 7, 1937. F. E. DEANS ET AL 2,101,494

CIRCULAR KNITTING MACHINE Filed March 4, 1956 3 Sheets-Sheet 2 1937. F. E. DEANS ET AL 2,101,494

CIRCULAR KNITTING MACHINE Filed March 4, 1936 5 Sheets-Sheet 3 4m A 1 mm m PM *N 237. \NWN 1. u 1 ,6 I n N 4Q %WN ma Patented Dec. 7, 1937 UNITED STATES PATENT OFFICE CIRCULAR KNITTING MACHINE ompany Application March 4, 1936, Serial No. 67,162 In Great Britain March 14, 1935 3 Claims.

This invention is concerned with improvements in or relating to circular knittingv machines.

In application No. 667,444 filed April 22nd, 1933 there is disclosed a knitting machine which is arranged to knit a draw thread into the fabric, between adjacent articles of a string of articles knitted by the machine, to facilitate the subsequent separation of the articles from one another by withdrawal of the draw thread from the fabric. In said machine the draw thread is knitted at a feed point which is additional to the main feed point of the machine.

In British Patent No. 400,623, there is disclosed (see Figures 7 and 8 of the drawings-of said patent) an arrangement whereby at the said additional feed point, there is provision for the knitting of a draw thread as above mentioned and also for the knitting of one layer of a French welt, the yarn for the French welt being supplied from a second yarn-feeder provided for that purpose.

In a machine embodying features of the present invention, the second yarn-feeder above referred to is utilized to feed yarn to one or both sets of the needles at the additional feed point simultaneously with the feeding of yarn to the same set or sets of needles at the main feed point, with the result that the knitted fabric (plain or ribbed as the case may be) is composed of two helices of yarn, which yarns may be of a contrasting nature, say differing in colour.

In the knitting of a hose or half-hose by a machine accordingto said British Patent No. 400,623, a series of operations involving the introduction and withdrawal of the stitch cam of the additional feed point into and from its working position-each of which events occurs in two separate stages-and the movements of the two yarn-feeders of that feed point into and out of feeding position, has to occur in a definite order and in a definite timing in relation to the rotation of the needle cylinders and to other operations performed by the machine. This series of operations is effected by an operating mechanism which starting from an initial position operates said stitch cam, yarn feeders and thread trapper and cutter devices associated with the yarn feeders, ina series of steps. At the completion of said series of steps, the operating mechanism automatically ceases.to operate. The series of operations above referred to occurs during the knitting of a relatively small portion of the hose or the like i. e. that portion of the hose in the general neighbourhood of the welt. In a machine of the present invention however the sec ond yam feeder has movements into and out of feeding position at relatively widely separated portions of the hose. For instance, the second yarn feeder moves into feeding position for the knitting of the leg portion of the hose from yarn fed from both feed points, moves out of feeding position for the knitting of the heel pouch from yarn fed only at the main feed point, moves again into feeding position for the knitting of the foot portion from the said two yarns, and finally 10 moves out of feeding position for the knitting of the toe pouch from yarn fed only from the main feed point. The series of steps in which the devices at the additional feed point are operated is thus formed into a plurality of sections brought about by pauses in the operative movements of said operating mechanism. These pauses are effected automatically, the operating mechanism starting and stopping its operative movements at the beginning and end, respectively, of each 00 of the sections. Now, if the operator found it necessary, say by reason of breakage of yarn, to start the knitting of a fresh article before the knitting of the preceding article in the string was finished, the operating mechanism for the devices at the additional feed point, in such circumstances, would in all probability not be in its initial starting position, and consequently would be out of step with the rest of the machine when the machine wasstarted for the knitting of the new article. With a view to preventing such a situation arising, the present invention provides a correcting mechanism which returns the operating mechanism to its initial position if it has accidently been displaced therefrom and therefore not in step with the rest of the machine.

In application No. 713,732 filed March 2nd, 1934 there is described a method of anchoring the ends of an additional helix of yarn which is knitted into the fabric at a portion thereof, from yarn supplied at an additional feed point, the ends of the additional helix being knitted into the fabric at the main feed point. In knitting machines as usually constructed and in cases in which the knitting of an additional helix is to stop just prior to the knitting of a heel or toe pouch, it is not possible to anchor the finishing end of the additional helix by the method above referred to for the reason which will now appear. Immediately preceding the knitting of a pouch, 0 the needles of about one half the needle circle are rendered inoperative, the sliders for these needles having-for this purpose long butts which can engage a cam brought into action at that time which moves the needles to non-knitting position. The sliders for the rest of the needles, i. e. those which are concerned in the knitting of the pouch, have short butts which are not long enough to engage the cam just referred to and consequently are not affected by it. In the machine described in said British Patent No. 400,623, the stopping of the knitting at the additional feed point is done in two stages. In the first stage, the stitch cam (or a bolt cam associated with the stitch cam) at that feed point, while the long butts are being acted upon by it, is moved outwardly from the needle cylinder a distance suflicient to permit the short butts later on to pass it unaffected but not suflicient for it to lose control of the long butts. At the second stage, the stitch cam is moved fully outward, out of range of the long butts, while the short butts are passing it. From the foregoing it will be apparent that the last needle to engage the stitch cam and therefore to knit at the additional feed point, is a needle associated with a long-butt slider, which needle is then moved to non-knitting position by the cam aforesaid acting upon the long butt of its slider. Hence this needle and the long-butt-slider needles adjacent to it no longer knit and the loose end of the yarn fed from and severed at the additional feed point cannot therefore be knitted into the fabric at the main feed point as required by the said method.

To obviate the above difliculty, the present invention provides an arrangement in which between the long-butt sliders and the short-butt sliders there are situated a. few (say six or eight) sliders having butts of medium length and the cam which engages the long-butt sliders to move their needles to non-knitting position for the operation of pouch formation, is adapted (for instance by being made narrower than usual) to permit the medium-butt sliders to pass it without being engaged by it. The medium butts, however, are long enough to engage the stitch cam at the additional feed point when the stitch cam is in the first of its two stages of withdrawal from operative position. Hence, at this time, the needles associated with the medium-butt sliders will knit at the additional feed point, and as they will not be moved to non-knitting position by the cam aforesaid, the loose yarn end held by them will be knitted into the fabric at the main feed point.

A construction of mechanism, illustrative of the present invention, will now be described with the aid of the accompanying drawings, and by way of example will be considered as applied to a machine of the kind described in .said British Patent No. 400,623.

In the drawings:-

Figure 1 is an elevation of part of the machine showing the lower or plain needle cylinder and devices associated with an additional feed point including a stitch cam for that needle cylinder;

Figure 2 is a plan of parts seen in Figure 1;

Figure 3 is an elevation of mechanismconcerned in the operation of the devices at the additional feed point;

Figure 4 shows in plan and partly in section, parts seen in Figure 3; and

Figure 5 is a diagram hereinafter referred to.

The machine described herein will be considered as arranged to knit ribbed hose or half-hose in the usual string formation, with a draw thread included between adjacent articles, each article having the usual type of welt, and with its sole hose including the sole, but not of course the pouches, will be knittedin two helices of yarn supplied from both feed points.

The machine to which the present correcting mechanism is applied, is provided with the customary control drum by rotation of which various changes in the knitting operation are brought about, the rotation of the control drum being controlled, as usual, by the main pattern chain (not shown) of the machine, which chain travels in timed relation with the rotation of the needle cylinders.

The operating mechanism of the present machine for the devices of the additional feed point, in general, is similar to the corresponding mechanism described in said British Patent No. 400,623 in connection with Figures 7 and 8 of the drawings thereof, and the driving and timing devices for that mechanism are, in the main, alike in the two machines.

The additional feed point comprises'a stitch cam I4 located in the cam box for the lower or plain needle cylinder I2, a feeder 220 for the draw thread, a feeder 260 for the yarn of the helix that is knitted at this feed point, a trapper and cutter device 230 associated with the feeder 220, and a similar device 204 associated with the feeder 260.

These devices are operated by a set of cams mounted upon and rotatable with a shaft 04. The cam 294 operates the stitch cam I4, the

cams

234 and 280, respectively, operate the

feeders

220 and 268, and the cams 256 and 202, respectively, operate the trapper and

cutter devices

238 and 284. In the drawings these cams are shown diagrammatically as plain circular discs, i. e. no attempt has been made to indicate the peripheral configuration which in practice the cams possess. In the present machine the feeder 268 is mounted upon its supporting spindle 210 so as to be able to swing in a vertical plane about a pivot 500, a spring 502 serving to press the tail end of the feeder against a cam plate 500 which guides the feeding end of the feeder 260 over its companion feeder 220, as the feeder 288 moves between feeding and idle positions.

The driving mechanism for the cam-carrying shaft 94 is shown in Figures 3 and 4. This mechanism comprises a ratchet wheel I00 which is operated by a pawl I02, pivoted at I04 on a lever I06, a spring I00 (Figure 3) tending to maintain the pawl I02 in engagement with the ratchet 'wheel. The lever I06 is pivoted at I09 on a. bracket III! secured to a fixed part 52. The lever I06 is actuated by a cam II2 through the agency of a push rod I which, as presently will be explained, is moved laterally into and out of the path of the cam I I2, so as to start and stop, respectively, the driving action of the cam H2 upon the pawl and ratchet device I00, I02. The cam II2 has two rises and falls and is attached to a part of the machine (a bevel gear wheel 0) which revolves at the same speed as the needle cylinder and so gives two movements to the vertical shaft 94 for each revolution of the needle cylinder when the push rod Ill is in the path of the cam H2. The push rod III is mounted to slide in a guideway formed in a lever III which is fixed on a shaft I20, journalled in bearings I22 on a fixed part of the machine frame. The lever H0 is moved by connections between it and cams on the control drum I26 of the machine one of which cams is shown at I24, so that at predetermined times it moves the push rod Ill into and out of the path of the cam H2. The

idle track for the push rod H4 is round the outside of the cam H2. The connections between the control drum I26 and the lever II8 comprise a lever I28 fixed to the shaft I20, and a push rod I30, which passes through an eye in the end of the lever I28 and is operated by the cams I24 on the control drum I26. The push rod I30 operates the lever I28 through a spring I32, so that, should the cam I24 come into operation (either when the control drum I26 is being turned by hand, or otherwise) at a time when the push rod I I4 is in its idle track i. e. on the outer side of the cam II2, the push rod II4 will be pressed against the side of the cam H2 and the spring I32 will be compressed until the end of the cam II2 has passed the push rod II4 when the latter will spring into the track of the cam II2. A spring I34 serves to return the push rod II4 to its idle track after the required number of turning movements has been given to the vertical shaft 94 by the mechanism just described.

In the present machine, the cam-carrying shaft 94 makes one complete revolution during the knitting of each article, and the ratchet wheel I00 which is driven by the pawl I02, has eighteen teeth (pins). The cams on the shaft 94 which operate the two

feeders

220, 268, the two trapper and

cutter devices

238, 284, and the stitch cam I4 are of single formation, i. e. they are so formed as to impart but one complete operation or series of operations appropriate to a single article upon the devices they actuate, during each revolution of the shaft 94.

During the knitting of an article the operating mechanism for the devices at the additional feed point acts as follows: The first movement of the shaft 94 is idle, that is to say, the shape and disposition of the cams upon it are such that no movement is given by the cams to the devices which they operate. At this time the long butt needle-sliders are passing the position of the stitch cam I4 which accordingly must not be moved inwardly otherwise these butts would be damaged. The second movement of the shaft 94 causes the stitch cam I4 to be given its first stage of inward movement which occurs during passage of the short butt needle-sliders past the stitch cam position, thus bringing the stitch cam I4 into the path of movement of the long butts but permitting the short butts to pass it unaffected. At this time the draw thread feeder 220 is moved into feeding position in readiness for the draw thread to be taken by the needles of the long butt sliders when these are acted upon by the stitch cam I4. At the third movement of the shaft 94, the stitch cam I4 is given the second stage of its inward movement while the long butts are being acted upon by it, so that the stitch cam I4 can act also upon the short butts when these reach this stitch cam. And the trapper 238 is {opened to release the end of the draw thread which is now being knitted into the fabric at the additional feedpoint by needles of the bottom cylinder while rib-knitting is being efiected at the main feed point. The fourth movement of the shaft 94 is an idle one. On the fifth movement of shaft 94 the stitch cam I4 is given the first stage of its outward movement while the long butts are being acted upon by it. On the sixth movement of shaft 94, the stitch ,cam I4, while the short butts are passing its position, is given the second stage of its outward movement, and at the same time the draw thread feeder 220 moves into inoperative position-and the draw thread is trapped and cut by the trapper and cutter device 238. This completes the operation of the knitting of the draw thread into the fabric.

The machine next forms the welt in the usual manner at the main feed point.

After the welt is knitted, the shaft 94 is given its seventh movement which, however, is an idle one. The eighth movement of the shaft 94 gives to the stitch cam I4 its first stage of inward movement, while the short butts are passing its position, and also brings the second yarn-feeder 268 into position to feed yarn to the needles of the long butt sliders when these butts in their turn reach and are acted upon by the stitch cam I4. The ninth movement of the shaft 94 gives to the stitch cam I4 the second stage of its inward movement in readiness to engage the short butts when these arrive at that cam, and the trapper 284 is opened to release the end of the yarn fed from the second yarn-feeder 268. The tenth movement of shaft 94 is idle. The fabric is now being knitted in two helices, one derived from yarn supplied at the main feed point and effected at both feed points, the machine being i provided, of course, at the additional feed point with a rib-stitch cam in the upper needle cylinder which cam is automatically adiusted into operative position when rib-knitting at that feed point is to be performed.

Rib-knitting now continues at both feed points until the heel pouch is to be knitted. At about this time the shaft 94 is given its eleventh movement during which the stitch cam I4 is given the first stage of its outward movement as the long butts are being acted upon by it. The twelfth movement of shaft 94 gives to the stitch cam l4 the second stage of its outward movement where it is out of range of all the butts and consequently knitting at the additional feed point ceases. During this movement of the shaft 94 the said second feeder 268 is moved into inoperative position and the yarn issuing from it is trapped and cut by the trapper and cutter device 284.

As before explained, in order to anchor at the main feed point this end of the yarn supplied from the second feeder at the additional feed point a few needle sliders (as shown in the diagram, Figure 5, of the needle circle) having medium-length butts 506 are inserted between the long-butt sliders 508 and short-butt sliders 5I0, which medium-length butts 506 can engage the stitch cam of the additional feed point when that cam is in the first stage of its outward movement, but are not long enough to engage'the cam aforesaid which, at the appropriate time, is automatically adjusted into position to engage the long-butt sliders 508 and move their needles to non-knitting position.

After the knitting of the heel pouch by the usual reciprocatory movement of the machine, rotary knitting is resumed for the foot part of the article with yam supplied from both feed points, the starting of knitting at the additional feed point being effected by movements thirteen to sixteen of the shaft 94, which movements cor respond with the seventh, eighth, ninth and tenth movements of that shaft and accordingly need not be described.

When the toe pouch is to be knitted, the shaft 94 makes its seventeenth and eighteenth movements, which correspond with its eleventh and twelfth movements already described, to suspend knitting at the additional feed point. The article is then completed by the knitting of the toe pouch in the usual manner. It will be understood that the ends of the yarn fed from the additional feed point during the knitting of the foot part of the article are also anchored in the fabric by the method hereinbefore referred to.

From the foregoing it will be appreciated that the eighteen movements of the shaft 94 are broken up into sections by pauses in those move ments. In order to ensure that the movements constituting each section shall be completed even though the control drum I26 is moved on so that the push rod I30 is free to fall off the end of the cam I24 which operated it, the following mechanism is providedz-The ratchet wheel I has formed in it, a series of notches I36 and a tooth I30 at one end of a bell-crank lever I40 is adapted to engage these notches. The other end I42 of said lever lies alongside (i. e. below as seen in Figure 4) a projection I44 on the lever III if the push rod I I4 in that lever is in its idle track. The lever I40 is pivoted at I46 on the bracket I I0 and the tooth I30, for the purpose of adjustment may, as shown, be formed on a block I40 adjustably secured to the lever end by a screw I50. In the position just described the vertical shaft 94 cannot be rotated as the projection I44 prevents the lever I40 from being turned in a direction which would remove the tooth I36 from the notch I36 with which it is engaged. When the lever H6 is moved in the operative position (as shown in Figures 3 and 4) by the action of a cam I24 on the control drum I26, the first movement of the ratchet wheel I00 places the end I42 of the lever I40-behind (i. e. as shown in Figure 4) the projection I44. lhe lever H6 is thereby held in its operative position, irrespective of the position of the control drum I26 until the tooth I36 on the lever I40 falls into a notch I36 by the action of a spring I52. The push rod H4 is then sprung back to its idle track by the action of the spring I34. A spring I54 (Figure 4) connected to the lever I06 and to a fixed part I56 tends to keep the lever pressed against the push rod II4.

From the foregoing it will be appreciated that provided the shaft 94 is in its correct angular position in relation to its driving mechanism (which comprises the cam H2 and the pawl I02 operated by that cam) there is but little probability that the timing of the movements of the shaft 94 in relation to the timing of other associated devices of the machine, will be disturbed. The timing of the said driving mechanism in relation to the rotation of the needle cylinders, is taken care of by the provision of a curved plate II3 (Figure 3) which is attached to the cam H2 and closes one of the gaps between the contiguous ends of the two portions of the cam H2.

In order to ensure that the shaft 94 is in its correct starting position before the knitting of an article by the machine is begun, the following correcting mechanism is provided which will automatically return the shaft to its starting position should it have been accidentally displaced therefrom.

This correcting mechanism comprises a springcontrolled correcting rod 6I2 similar to the rod I30 and located below and somewhat to one side of the rod I30. One end of the correcting rod 6I2 is adjacent the control drum I26 and the other end of this rod is connected by an adjustable vertically-disposed link II4 to one end of a lever 6I6 arranged to turn about a pivot pin 6I6 carried on the bracket H0. The other end of this lever is upturned to form a cam follower arranged in the path of a cm 620 on the underside of the ratchet wheel I00 on the shaft 94. Secured to the shaft I20 and arranged alongside the lever I26 is a depending arm 622, the lower end of which is Just above a collar 624 on the correcting rod 5I2. This collar 624 is loose on the rod 5I2 but is backed up by a spring 526 that encircles the rod and bears against a collar 528 fast to the rod. The correcting rod 5I2 is moved endwise at times by a cam 630 on the control drum I26.

If the shaft 94 is in its correct starting position, the correcting rod 5I2 will merely be moved endwise idly against the action of its spring 6I3 by the cam 530 on the control drum I26. But if the shaft 94 is displaced from its starting position, the cam 520 on the ratchet wheel I00 will depress one end of the lever 5I6, thereby raising its other end and lifting the correcting rod 6I2 so as to bring the loose collar 524 thereon alongside the free end of the depending arm 622. When therefore the correcting rod 5I2 is moved endwise by the cam 530 on the control drum I26, the loose collar 524 on the rod will engage the depending arm 522 and, by way of force transmitted by the spring 626 on the rod, will turn the shaft I20 in a direction to bring the push rod I I4 into the path of the cam I I2 and thereby start the driving mechanism for the shaft 94 into action. The shaft 64 will thus be turned until it arrives in its starting position wherein the cam 520 on the ratchet wheel I00 will have been removed from engagement with the follower of the lever 5I6, permitting the lever 5I6 to turn and thereby allow the correcting rod 5I2 to fall into its lower and idle position.

Although in the foregoing description the controlling mechanism has been described as giving various movements to the stitch cam of the additional feed point, in practice it is preferred to give such movements to a pilot cam which, when operative, deflects the slider-butts to the stitch cam proper. Further, this stitch cam itself is preferably made adjustable for stitch-length variation conveniently by means of operative connections between it and the mechanism for similarly adjusting the stitch cam of the main feed point.

We claim:

1. A knitting machine comprising a stitch cam movable between a needle-actuating position and an idle position, a plurality of thread feeders each independently movable between a threadfeeding position and an idle position, thread trapper and cutter devices each associated, respectively, with one of said feeders to trap and cut and to release thread fed from said thread feeder, operating mechanism for operating said stitch cam, thread feeders, and trapper and cutter devices, which operating mechanism during the knitting of an article by the machine is moved from an initial position in a series of steps formed into sections by pauses in the movement of said mechanism at predetermined points in the operation of the machine, driving means for driving said mechanism, stopping means for automatically stopping the ,driving action of said driving means at the end of each of said sections, starting means for starting said driving action at the beginning of each of said sections. pattern control means, devices on said pattern control means for actuating said starting means, and a correcting mechanism comprising an adjustable element, operative connections between said element and said operating mechanism arranged to maintain said element normally in operative relation with said starting means but to move said element out of such relation when the said operating mechanism is in its initial position, and, a device on the pattern control means for operating said element at a time in the operation of the machine at which the operating mechanism should be in its initial position, whereby if the relation between the pattern control means and the operating mechanism has been disturbed, the starting means will be actuated by said element and will cause the driving means to drive the operating mechanism into its initial position.

2. A knitting machine comprising a stitch cam movable between a needle-actuating position and an idle position, a plurality of thread feeders each independently movable between a threadfeeding position and an idle position, thread (rapper and cutter devices each associated, respectively, with one of said feeders to trap and cut and to release thread fed from said thread feeder, operating mechanism movable from an initial position in a series of steps for operating said stitch cam, thread feeders, and trapper and cutter devices, pattern control means for starting said operating mechanism into operation from said initial position and for thereafter stopping and restarting said mechanism thereby forming said series of steps into sections, driving means for said operating mechanism comprising a continuously moving cam, a pawl and ratchet device, and operative connections between said cam and device whereby said device is adapted to be driven by said cam, a disconnectable element in said operative connections under control of said pattern control means, a locking device operated by the pawl and ratchet device for maintaining said element in connecting position .until each section of said series of steps is complated, and means operatively connected with the pawl and ratchet device and also under control of said pattern control means for moving said disconnectable element into connecting position if the correct positional relationship of the pawl and ratchet device with the pattern control means is disturbed.

3. A knitting machine comprising a stitch cam movable between a needle-actuating position and an idle position, a plurality of thread feeders each independently movable between a thread-feeding position and an idle position, thread trapper and cutter devices each associated, respectively, with one of said feeders to trap and cut and to release thread fed from said thread feeder, operating mechanism movable from an initial position in a series of steps for operating said stitch cam, thread feeders, and trappers and cutter devices, a control drum, devices carried thereby for starting said operating mechanism into operation from said initial position and for thereafter stopping and restarting said mechanism thereby forming said series of steps into sections, driving means for said operating mechanism comprising a continuouslymoving cam, a pawl and ratchet device and operative connections between said cam and device whereby said device is adapted to be driven by said cam, a disconnectable element in said operative connections under control of the said devices on the control drum, a locking device operated by the pawl and ratchet device for maintaining said element in connecting position until each section of said series of steps is completed, a cam driven by said pawl and ratchet device, a member adjustable into and out of operative connection with said disconnectable element, operative connections between said last-named cam and said member for effecting such adjustment of said member, and a device on the control drum for actuating said member.

FREDERICK EDWARD DEANS. CHARLES FREDERICK MANGER. GEORGE ALFRED BUSWELL.