US2353973A - Knitting machine - Google Patents

Description

July 18, 1944.

A.. SHORTLAND 2,353,973

KNITTING MACHINE Filed March.22, 1943 3 Sheets-Sheet l I nvenlor ,flrt'har' Shortland;

A torn July 18, 1944. A SHORTLAND 2,353,973

KNITTING MACHINE I Filed March 22, 1945 s Sheets-Sheet 2 F/GZ.

In venior firth ur Short land,

By W

Allard;

July 18, 1944.

A. SHORTLAND' 73- KNITTING MACHINE Filed Mar ch 22, 1943 3 Sheets-Sheet-3 V In ventor flrthur Short la nd,

By I Atlor y Patented July 18, 1944 UNl'lED STATES 'nm'r'rme MACHINE Arthur Shortland, Leicester, England, assignor to Mellor Bromley and Co. Limited, Leicester,

England Application March 22, 1943, Serial No. 480,074

In Great Britain December 31, 1941 1c- Claims. (Cl. 66-126) This invention comprises improvements in draw mechanism for rotary and straight bar knitting machines of the type having a line of needles and at least one element which, in the knitting process, is reciprocated lengthwise of said line and the amplitude of travel of which requires to be varied. In the most important application of this invention the said element is a thread carrier or carrier bar. In machines of this type (of which the Cottons Patent is the modern example) the draw mechanism by which the thread carriers are reciprocated commonly comprises a friction rod which is reciprccated with a constant amplitude (usually by a rotary draw cam which drives a piv oted draw lever through the medium of a draw bar having trucks engaging the periphery of said cam) and carries at least one friction box that is connected to any selected carrier bar; the amplitude of traverse of the latter is variably determined by adjustable end stops so that when the traverse of a carrier bar is terminated by contact with an end stop the friction rod slides through the box for the remainder of the traverse of said rod. Hence shock and frictional losses are inseparable from this known mechanism, and the object of the present invention is the provision of variable draw mechanism which obviates friction boxes and is not subject to these a disabilities.

The present invention provides, in a knitting machine of the type specified, draw mechanism comprising a cam track, a follower, engaging said track, for movement to and fro thereby,

which follower is connected to the reciprocating 85 element, and means for modifying said track to vary the amplitude of travel of said element. According to a feature of the invention there are two members that are simultaneously oscillatable, a cam track formed on the two members 40 and comprising a helical part on one and a part of reduced pitch with a lead-in thereto on the other, and means for eflectlng relative circumferential and axial adjustment between said two members to vary the length of the cam track 46 while keeping the lead-in blending with the helical part of the track. More specifically the said mechanism may comprise a cam having a helical cam track, mounted for oscillation (or rotation to and fro) about its longitudinal axis, and so an annular member, at least at one end of said cam and partaking of the said oscillation, having a circumferential track for the follower and a lead-in track portion blending into the helical helical track to the circumferential portion and vice versa. It will therefore be appreciated that by this adjustment of the annular member the effective axial length of the cam track is varied with a corresponding variation in the traverse of the carrier bar or other element. In general there will be an annular member aforesaid at each end of the cam; in some cases the two members will be adjusted symmetrically and in others differing adjustments will be imparted to hem.

The foregoing and other features of the invention set out in the appended claims are incorporated in the constructions that will now be described with reference to the accompanying drawings, in which Figure 1 is an elevation, to some extent diagrammatic, showing a draw cam according to the invention and associated parts;

Figures 2 and 3 are sectional views showing certain details;

Figure 4 is a cross section through a Cottons Patent orother straight bar or rotary knitting machine incorporating the invention;

Figure 5 is a perspective view showing carrierlocating mechanism.

The draw mechanism comprises a cylindrical drum l0 mounted on a shaft H which is oscillated first in one direction and then in the other 9 by suitable mechanism. This drum H) has its periphery cut with a helical cam track or groove E2 the axial length of which is such as to provide the maximum length of draw required. This groove I2 is engaged by a follower I3 which is connected by mechanism hereinafter described to a thread carrier bar it or any selected carrier bar so that as the cam is oscillated to-andfro the carrier bar is reciprocated. Surrounding each end of the drum there is a sleeve (15a, l5b) which is sliclable and rotatable on it, each sleeve having a peg E6 or its equlvalentengagedin the helical. track I2. Each sleeve also has a circumferential track It cut into it for somewhat less than 360; one end l8 of this circumferential track is blind and the other end l8" merges with a curved lead-in portion into the helical-track I2. It will therefore be appreciated that as the sleeves I511, I512 are adjusted axially on the drum l0 they rotate thereon in such manner that the said lead-in portions 18 always register with the helical track l2 and the efiective length of the cam trackis thus varied. As the drum in revolves the follower i3 traverses the helical track 12 and towards each end of the rotation in either track whereby the follower may pass from the 5s direction passes from the track in th drum by circumferential portion of the track IS on the appropriate sleeve. The curved blending portion provides for the deceleration of the follower, and the circumferential portion provides for a rest period thereof. Likewise when the drum reverses the follower travels in the reverse direction and the curved blending portion ll" accelerates the follower from rest.

It will be appreciated that the track I! in each sleeve is of necessity formed at a greater radius than that of the track in the drum, and that pro vision must be made for the follower to pass smoothly from one to the other. For this purpose each sleeve Ilia and Nb is provided at the end of its curved blending portion ll" with a ram'p l9 which engages in the helical track It, and the follower I3 is spring loaded (by means indicated diagrammatically at 20) to ride up and down the ramp I! in passing from the helical track I! to the blending portion l8" and vice versa.

The sleeves lia, b are adjusted in any suitable manner. For example they may each be provided with an annular collar or groove ll engaged by a shoe or slipper II which is moved axially of the drum through suitable mechanism. These shoes or slippers may be moved by the fashioning screws through connections indicated at 22, or by a separate screw -23 which may be operated in step with the fashioning screws. It is desirable, however, that the step-by-step variations in the draw should be accurately and positively determined. For this purpose the interior of each sleeve Ha, lib is provided with a series of annular grooves 24 the pitch of which corr sponds to the minimum step in the draw variations; for example'the grooves may have a twoneedle pitch. Extending lengthwise of the drum Ill in its interior there is a roller 25 mounted to rwk about an eccentric axis 28 which extends parallel with the drum axis. This roller 25 (or at least each end of it) is grooved in a similar manner, and it is so arranged that owing to its eccentricity it may be rocked between a locking position in which it engages the grooves 24 in the sleeves and an inoperative position in which it is buried within the periphery of the drum. Means are provided for rocking it to the locking position after the sleeves lia, lib have received each adjustment, and to the inoperative position preparatory to each adjustment of the sleeves. For this purpose the roller may be provided with a forked arm 21 projecting from the drum periphery and adapted to engage a striking pin 28 as the drum oscillates.

This striking pin may itself be movable into and out of operative position.

The application of the present draw mechanism to a Cottons patent or other rotary or straight.

bar knitting machine is illustrated in Pig. 4. This figure only shows those parts of the machine that .are desirable to identify it (such for example as the cross frame I! incorporating front rail 8|, k rail 3 template'rail 38 and head rail 84,

and the needles II and sinkers It) or are helpful in understanding the invention, since the remainder or the machine is well understood in the art and needs no illustration or description herein.

'I'hecamdrum" It occupies a rearwardly inclined attitude at the back of the machine, and

the mechanism for oscillating it about its axis is in this example illustrated as consisting of a draw cam -31 rotatingat an appropriate speed (I eiproeated lengthwise of the on the camshaft 88 and oscillating a draw lever 38 to the free end of which a rack 40 is connected; the latter drives a shaft II that extends horizontally lengthwise of the machine and is connected to the drum i0 through bevel gearing 42. The follower I3 is carried by a bracket 43 travelling on guides 44 and has two carrier racks 45, 46 connected to it. The rack is for the main carrier rods Na and rack 48 is for the plating carrier rods lib and in order to preserve. the requisite plating lead the plating rack 48 is driven through a lost-motion connection comprising a finger 41 on bracket 43 working between spaced stops 48 on the rack. The racks 45, ll respectively drive pinions 49, 50 that are movable axially into engagement with the required carrier rods by mechanisms 5|, 52, said rods being provided with racks of teeth as shown in Fig. 5.

Means are also preferably provided for ensuring that the carrier bars II are located correctly and positively at each end of their particular draw, and after each narrowing movement. In this, use is made of the racks of teeth with which they are provided which teeth may have a two-needle pitch. Associated with said racks there is a plateor other member 53, Fig. 5, carrying teeth which are adapted to mesh with those of the racks. At the end of each draw, this plate is brought into engagement with the teeth of all the carrier bar racks, and preparatory to and during each draw it is disengaged from the racks to permit the selected carrier bar to be traversed. One mechanism for controlling this carrier-locking device is indicated at 54 in Fig. 4.

The sleeves 15a, |5b may be adjusted in con,- formity with the adjustment of the fashioning screws 55 of the fashioning mechanism 56 (itself of well understood construction) so that as the fabric under production is narrowed or widened the draw is correspondingly adjusted. One

. means for effecting this is diagrammatically illustrated in Fig. 4. One rack mechanism 51 for the screws 55 is operated by a truck lever 58 having other for driving the left-hand splicing carrier.

9. third for driving the split foot and block toe carriers. These mechanisms may be arranged substantially as in Fig. 4. In the case of the splicing carriers the two sleeves of each drum are given differing adjustments because one end of the traverse of each splicing carrier must correspond to a selvedge edge of the blank and the other end of its traverse must correspond to the inner margin of the splicing. Therefore the sleeve at one end of each splicing drum may be controlled by the same mechanism that controls the sleeves of the main carrier drum (e. g. by

means such as that illustrated in Fig. 4 control- I ling the fashioning screws), and the sleeve at drum by a sepa draw cam partaking of movements about an axis and the amplitude of travel or draw of which element requires to be varied, which draw mechanism comprises an oscillatory draw cam provided with a cam track, a follower, engaging said track, for movement to and fro thereby which follower is connected to the reciprocating element, and means for modifying said track to vary the amplitude of travel of said element.

2. Mechanism according to claim 1, comprising two members that are simultaneously scillatable, a cam track formed on the two members and comprising a helical part on one and a part of reduced pitch with a lead-in thereto on the other, and means for effecting relative circumferential and axial adjustment between said two members to vary the length of the cam track while keeping the lead-in blending with the helical part of the track.

3. Mechanism according to claim 1, comprising a cam having a helical cam track mounted for oscillation about its longitudinal axis, and an annular member at least at one end of said cam and partaking of said oscillation, having a circumferential track for the follower and a leadin track portion blending into the helical track whereby the follower may pass from the helical track to the circumferential portion and vice versa.

4. Mechanism according to claim 1, comprising a cam, having a helical cam track, mounted for oscillating about its longitudinal axis, an annulan member at each end of said track and partaking of said'oscillation, each of which members has a circumferential track for the follower and a lead-in track portion thereto, blending into the helical track, for thev passage of the follower from the helical track into the circumferential portion and vice versa, and means for adjusting said members axially to vary the amplitude of travel of said element.

5. Mechanism according to claim 1, comprising two members that are simultaneously oscillatable, a cam track formed on the two members and comprising a helical part on one and a part of reduced pitch with a lead-in thereto on the other, a ramp between the helical track and the lead-in, and means for effecting relative circumferential and axial adjustment between the two members to vary the length of the track while keeping the lead-in blending with the helical part of the track; combined with means for permitting the follower to give in travelling up and down the ramp.

6. Draw mechanism for a straight bar knitting machine of the type having a line of needles and at least one element which in the knitting process is reciprocated lengthwise of the line of needles and the amplitude of travel or draw of which requires to be varied, which draw mechanism comprises a cam itself comprising two members that are simultaneously oscillatable, and a cam track formed on them and comprising a helical part on one and a part of reduced pitch with a lead-in thereto on the other; a locating device on the member formed with thelead-in for engaging in said helical part of the track andfor causing the lead-in to blend with said helical part during relative axial and circumferential adiustment between the two members, means for 7. Draw mechanism for a straight bar knitting machine of the type having a line of needles and at least one element which in the knitting process is reciprocated lengthwise of the line of needles and the amplitude of travel or draw of which requires to be varied, which draw mechanism comprises a draw cam, means for oscillating it, and a follower connected to the reciprocating element and movable to and fro by the cam, and which draw cam comprises two members that are simultaneously oscillatable, a cam track formed .on the two members and comprising a effecting said adjustment, a follower engaging.

helical part on one and a part of reduced pitch with a lead-in thereto on the other, means for effecting relative circumferential and axial adjustment between said members to vary the effective length of the cam track and the draw of the aforesaid element whil keeping the leadin blending with the helical part of the track, and means for locking the two members in the position to which they are adjusted.

8. For a straight bar knitting machine of the type having a line of needles and at least one carrier which, in the knitting process, is reciprocated lengthwise of the needles to feed thread thereto and the amplitude of travel or draw of which carrier requires to be varied; draw mechanism for said carrier which comprises a single oscillatory draw cam having a cam track, a follower engaging said track for movement to and fro thereby, means connecting the follower to the. carrier, and means for modifying said track to vary the draw of the carrier.

9. In a straight bar knitting machine of the type having a line of needles, a carrier which, in the knitting process, is reciprocated lengthwise of the line of needles to feed thread thereto, and fashioning mechanism including points that are displacea'ble along the line of the needles; the combination with means for moving said points lengthwise of the line of needles, of draw mechanism for the carrier which mechanism comprises an oscillatory draw cam having a cam track,,a follower engaging said track for movement to and fro thereby, a connection between said follower and carrier, and means for modifying said track to vary-the amplitude of travel or draw of the carrier in accordance with the said movement of the fashioning points.

10. In a knitting machine of the type having a line of needles, a thread carrier movable along said line of needles to feed thread thereto, and fashioning mechanism, including screws and means for racking them, for fashioning the edges of the fabric being produced,

in which machine the draw of the carrier requires to be varied in conformity with the operaof which members has a circumferential track and a lead-in track portion blending into the aforesaid helical track, means for oscillating said cam and annular members, a follower for engaging said track and for passing between the helical part and the circumferential parts by way of the lead-in portions during said oscillation, and means for racking said annular members towards and away from one another as the fashioning screws are racked.

, ARTHUR SHORTLAND.

fashioning

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