US2917914A

US2917914A - Yarn feeding means for knitting machines

Info

Publication number: US2917914A
Application number: US608875A
Authority: US
Inventors: Shortland Arthur
Original assignee: Individual
Current assignee: Individual
Priority date: 1955-09-19
Filing date: 1956-09-10
Publication date: 1959-12-22
Anticipated expiration: 1976-12-22
Also published as: DE1102961B; GB810305A

Description

Dec. 22, 1959 A. SHORTLAND YARN FEEDING MEANS FOR KNITTING MACHINES 3' Sheets-Sheet 1 Filed Sept. 10, 1956 1 2 m n, w N f U Dec. 22, 1959 A. SHORTLAND 2,917,914

YARN FEEDING MEANS FOR KNITTING MACHINES Filed Sept. 10, 1956 3 Sheets-Sheet 2 Dec. 22, 1959 A. GSHORTLAND 2,917,914

YARN FEEDING MEANS FOR KNITTING MACHINES Filed Sept. 10, 1956 3 ShGGfS-Shflt 3 JLJ LJLJL "42 ugw United States YARN, FEEDING MEANS FOR KNITTING MACHINES Claims priority, application Great Britain September 19, 1955 '5 Claims. (Cl. 66132) This invention relates to yarn feeding means for knitting machines, and has for -its object to provide a generally improved, compact and efficient form of unitary mechanism for this purpose which is readily adjustable to vary the speed of the yarn or yarns being fed, according to knitting requirements, and is capable of simultaneously feeding a plurality of yarns to separate feeders.

The term yarn used in this specification is intended to cover a yarn or thread of any appropriate character.

The mechanism provided by this invention comprises, in combination, a rotary yarn feeding component (hereinafter for convenience referred to as a drum) which has a yieldable slip-resisting surface, and means whereby the said drum can be driven at a uniform, but readily variable, speed related to the speed of the knitting machine upon which the mechanism is mounted.

The improved mechanism may advantageously include, for the guidance of each relevant yarn to be fed to needles of the machine, a pair of yarn guides angularly spaced apart about and near to the cylindrical surface of the yarn feeding drum, the arrangement being such that a yarn properly threaded through both guides extends partially around the said drum en route from a yarn supply to the needles. Thus, the yieldable slip-resisting surface of the drum frictionally engages the yarn in a more or less positive manner and drives it forward at a linear speed corresponding to, or at least commensurate with, the rotational speed of the drum. It is the intention that each yarn shall normally be lapped around approximately half or a little more of the circumference of the drum, although provision is preferably made for varying the extent 'of this lap, by a relative adjustment of the yarn guides of each pair towards or away from one another] Such a variation in the circumferential extent of the contact with the drum results in the yarn being driven more or less powerfully, according to requirements. In this way any slackness, or excessive tension, in a running yarn can be obviated.

The surface of the yarn feeding drum may be covered or treated with any appropriate yieldable slipresisting material.

The yarn feeding drum may advantageously be made of a relatively light material, and the length thereof will be determined by the maximum number of yarns intended to be fed thereby. In this regard it is possible simultaneously to feed by the same drum as'many as, say, eight yarns to a corresponding number of individual feeders. In such'a case the drum has associated therewith as many pairs of yarn guides as there are yarns in the full complement of yarns to be fed, and these pairs are equally spaced'apart axially, i.e. along the drum. With such mechanism in use, not only can the yarn guides of the several pairs be relatively adjusted simultaneously, but any variation in the speed of rotation of the yarn feeding drum affects all of the yarns to the same extent. That is to say, by a single adjustment of the drum driving means, the linear speed of all the yarns being fed by the drum will be simultaneously varied the same amount.

2,917,914 Patented Dec. 22, 1959 The rotary drum may advantageously be frictionally driven from any appropriate rotating part of the knitting machine, through the medium of suitable gearing, provision being made for practically infinite variation, between limits, of the rotational speed of the drum.

In a convenient embodiment of the invention, a friction driving wheel, arranged with its periphery in contact with a plane face at one end of the drum, is rotatable together with a spindle adapted to be driven at a substantially uniform predetermined speed from a rotating part of the machine, this driving wheel being adjustable axially suchwise as to vary the radial distance between it and the axis of the drum. Consequently, by setting the friction driving wheel nearer to the axis of the drumthe speed of the latter will be increased, and, vice versa. The hub of the driving wheel may conveniently be slidable axially along the driven spindle, axial movements being imparted to the said hub for the purpose of adjusting the friction driving wheel by manually operable screw or equivalent means.

In order that the invention may be more clearly understood and readily carried into practical effect, a specific constructional form of the improved yarn feeding unit suitable for application to a multi-feed circular knitting machine of the cylinder and dial type and embodying the foregoing and other features of the invention will now be described, by way of example, with reference to the accompanying drawings, wherein,

Figure 1 .is a general perspective view of the said yarn feeding unit, I

Figure 2 is an end view of the same as seen in the direction of the arrow A in Figure 1,

Figure 3 is a vertical sectional view taken on the line 111111 of Figure 2, and

Figure 4 is a detail sectional view illustrating a smaller yarn feeding drum fitted upon the unit.

Like parts are designated by similar reference characters throughout the drawings.

In the illustrated example, the yarn feeding drum 1 consists of alight cylinder of aluminum a little over 5" in length and having an external diameter of approximately 2%. The circumferential surface of the drums 1 is wholly covered with a uniformly thick covering of silicon rubber 2. A covering of silicon rubber is found to be eminently satisfactory for the intended purpose. Although such rubber exercises the required degree of grip on a yarn, such as that indicated at Y in each of

Fig ures

1 and 2, a covering of this particular material is nevertheless of such a nature as to give to an extent sufficient to prevent a broken yarn from wrapping around the drum 1. The inner end of the light cylinder constituting the drum 1 is closed by a circular end plate or disc 3 presenting a plane outer surface 351 (see Figure 3) for contact with a small friction driving wheel 4 hereinafter to be described. The diameter of the end plate or disc 3 is the same as the external diameter of the aluminium cylinder, and the inner side of the said plate or disc is formed with a central boss 5 to enable it to'be fitted upon and to be rigidly secured to the inner end of a rotary tube 6 which, as depicted in Figure 3, is concentric with and constitutes a hub-like carrier for the cylindrical drum 1. The tube 6 is mounted to rotate freely about a horizontal spindle 7 which at its inner end is secured, by means of a grub screw 8, within a bored boss 9'ex'tending outwardly from the main bracket 10 of the unit. The inner end of therotary tube 6 is suitably counterbored at 621 to receive a bush 11 which is arranged to turn about the boss 9 and, at its inner end, is formed to receive a plain bearing '12. -In a similar way, the

outer end of the tube 6 is counter-bored at 6b to receive a bearing bush 13 in which is fitted another'pla'in bearing'ltl. The

plain bearings

12 and 14 may, if desired, be

replaced by anti-friction bearings of the needle or roller type. The central tube 6 is spring loaded, suchwise as to hold the outer plane face 3a of the end plate or disc 3 firmly in contact with the friction driving wheel 4, by means of a compression spring 15. As will be seen in Figure 3, the spring surrounds the outer end portion of the horizontal spindle 7 and is interposed between an abutment, e.g. a washer 16, on the latter andan end thrust anti-friction bearing 17 located, as shown, adjacent to the outer end of the bush 13. The outer end of the drum 1 is closed by a cap 18 which is centrally bossed at 18a to fit upon the concentric tube 6 and is also provided at its periphery with an inwardly directed annular flange 18b which is engaged within a counterbore in the drum 1. A somewhat similarly flanged and centrally bossed drum-supporting plate 19 is fitted with in the yarn feeding drum 1 intermediate its ends. To receive the said plate 19 the drum is counterbored at its inner end so as to provide an annular shoulder 20 against which the plate can be located. The entire drum 1, complete with its end cap 13 and supporting plate 19, is adapted to be engaged, as a unit, with the'central rotary tube 6 by an axial sliding movement. When fully engaged with the tube 6 by pushing it up to the inner face .of the circular end plate or disc 3, the drum 1 is secured to the said tube e.g. by means of a radially extending screw 21. Thus, by withdrawing this screw, the drum 1 can be readily removed from the tube 6, as occasion may demand.

The friction driving wheel 4, which may advantageously be made of nylon or any appropriate rubber or rubber-like composition, is mounted upon a hub 22 which is rotatable together with, but is slidable axially up and down, a vertical spindle 23 extending at right angles to the drum axis a. The spindle 23 is mounted for rotation in any suitable

anti-friction bearings

24 and 25 provided in the main bracket 10. The lower end of the vertical spindle 23 has secured thereto a pinion 26 which, when the unit is mounted upon a knitting machine of the cyl inder and dial type, is arranged in mesh with a gear ring 27, secured upon a gear 28 (Figures 2 and 3) arranged to be driven from the dial. For the purpose of moving the hub 22 up and down the spindle 23 there is provided a rotatable vertical screw 29 with which cooperates a nut 30 having integral therewith a radially extending finger 31 the outer end of which is engaged in a circumferential groove 32 formed in the said hub. The screw 29 thus extends parallel to the spindle 23 and is mounted to turn in vertically aligned bearing holes formed respectively in the upper and lower portions of the bracket 10. The screw 29 is prevented from any axial move ment so that, when it is rotated in one direction, the nut 30 will be caused to travel upwards and when the screw is rotated in the reverse direction the said nut will travel downwards. Accordingly, although the nylon, rubber or like friction driving wheel 4 is driven from the machine at a uniform speed, the rotational speed of the yarn feeding drum can be readily varied, within limits and according to requirements, by effecting an axial adjustment of the nut 30, such an adjustment serving to vary the radial distance between the drum axis a and the point of contact of the wheel 4 with the driven circular end plate or disc 3. Thus, with the wheel 4 in the full line position indicated in Figure 3, the drum 1 rotates at its highest speed, whereas with the said wheel in the chainline position the lowest drum speed is obtained.

For effecting rotation of the screw 29 manually, and hence also manual adjustment of the nut 30 as required, there is provided a peripherally milled knob 31 which is rigidly secured to the screw, near the lower end thereof, and a portion of which is arranged to protrude through an aperture 32 formed in the back of a hollow part of the bracket 10. Means of any suitable character may be provided to secure the knob 31 against rotation after an adjustment. If desired, moreover, the periphery of a vernier setting dial 33 combined with the knob 31 may be appropriately calibrated for use in conjunction with a fixed index on the bracket.

In an alternative constrution, not shown, the friction driving disc may be rigidly secured to the vertical spindle, in which instance the latter itself may be adjustable up and down and the gear 28 may be made sufliciently thick to ensure maintenance of driving engagement between the said gear and the pinion 26 during adjustments. For instance, the vertical spindle may conveniently be mounted for rotation in an axially movable non-rotatable bush to which axial movements can be readily imparted by manually operable rack and pinion or equivalent means.

To provide a different range of drum speeds, the pinion 26 at the lower end of the driving wheel spindle 23 may be interchangeable with another having a different number of teeth. To enable such an interchange to be effected, the main bracket 10 may be made to swing in and out upon its support 34 on the machine, e.g. about the axis of a pivot screw 35. After a fresh pinion has been intermeshed with the gear ring 27, by turning the bracket 10 inwards about the pivot screw 35, the unit may be easily secured in position by re-tightening the said screw. In the specific example illustrated the support 34 is constituted by a guard for the gear ring 27 and gear 28.

On a supplementary bracket 36 attached to the main bracket 19 of the unit is adjustably secured the inner end of a fixed horizontal bar 37 which, as shown in Figure 1, is drilled at regular intervals therealong to re ceive a longitudinal series of uniformly spaced yarn guiding eyes 38 or equivalent. This bar 37, which is disposed near to and parallel with the surface of the yarn feeding drum 1, is of approximately the same length as the latter. As will be seen, the inner end 37a of the bar 37 is slotted to permit of adjustment of the bar up or down Within the limits of the slot. Another similar adjustable bar 39, furnished with eyes 40 respectively disposed in line with the corresponding eyes 38 of the bar 37 is mounted adjacent to the drum on an extension 36a of the supplementary bracket 36. The yarn guide bars 37 and 39 are accordingly adjustable one or each in relation to the other suchwise as to vary the circumferential extent of the contact of the feeding yarns, such as Y, with the drum 1. That is to say, by appropriate relative adjustment of the

bars

37 and 39, the extent of the top of the yarns around the circumference of the drum 1 can be varied, according to knitting requirements.

To enable different yarns to be fed at respectively different speeds in one and the same machine, several alternative expedients may be adopted. For instance, two or more of the cylindrical yarn feeding drums may be fitted onto the machine and arranged to be driven from a common rotating part of the latter, provision in this case being made for varying the rotational speeds of the drums individually.

Different ranges of speeds can also be obtained by exchanging a cylindrical drum for another of a different diameter, utilising the same circular end plate or disc 3. Thus, for example, and comparing Figure 3 with Figure 4, it will be appreciated thatthe drum 1 may be removed from the central rotary tube 6 and replaced by another drum 1 of a substantially smaller diameter. In the case of the small drum there is no need to provide an intermediate drum-supporting plate since the inner end of the drum 1' can, as shown in Figure 4, be supported directly upon the boss 5 of the circular end plate or disc 3. The outer end of the said small drum 1' is closed by a cap 18' which is also made to fit upon the tube 6. A screw 41 is employed to secure the drum 1 to the rotary tube. Accordingly, in one and the same machine, yarn feeding units fitted with drums of respectively different diameters may be used.

Again, if one and the same cylindrical yarn feeding drum is covered or treated with adjoining bands of contrastlng materials which are slip-resisting to respectively different degrees, yarns lapped around the drum and engaged with the different bands will be fed at different speeds.

A similar result could be achieved by providing upon one and the same drum adjoining slip-resisting bands of clrcumferential portions of slightly varying external diameters. Such bands or portions may be fitted upon or combined with a sleeve which is secured upon the cylindrical drum. Or, for the same purpose narrow drums of varying diameters may be combined together to provide a unitary rotary component.

Again, to feed different yarns at different speeds, the circumferential extents of the contact of the yarns with one and the same drum may be commensurately different.

At 42 in Figure 2 is indicated a stop motion device equipped with a pivoted wire dropper 43 arranged to be engaged and normally held up in the full line position shown by the yarn Y. If the yarn breaks or runs out, the dropper 43 falls to the chain line position to initiate stoppage of the knitting machine. A series of such stop motion devices is indicated in chain lines in Figure 3.

At 44 is shown an adjustable rod by which yarns running from the drum 1 to the stop motion devices 42 are supported. This rod may conveniently be made of steel and covered with glass.

In lieu of a cylindrical drum, there may be provided a rotary yarn feeding component composed of a plurality of co-axial and adjoining sections each of truncated conical form.

It is also within the scope of the invention to provide two drum units of different diameters and to drive these simultaneously at the same speed from a common drive source: in this case the said drum units may conveniently be arranged one above the other pick-a-back fashion.

I claim:

1. In a knitting machine, a yarn feeding mechanism comprising, in combination, a rotary yarn feeding drum of open cylindrical form, two parallel spaced longitudinal rows of yarn guides extending axially alongside the drum near to the cylindrical surface thereof, said guides being arranged in axially spaced pairs and each of said pairs enabling an individual running yarn appropriately threaded therethrough to extend partially around the drum in contact therewith whereby the drum can feed simultaneously as many yarns as there are pairs of guides, said drum having a covering of a slip-resisting material which is adapted to exercise a grip on yarns guided around the drum as aforesaid and yet is capable of yielding to an extent suflicient to prevent a broken yarn from wrapping around said drum, a carrier for said drum concentrically rotatable and in an interior engagement with said drum, a member forming a closure for one end of said drum and rotatable with said drum through engagement with said carrier, said member presenting a plain outer face, a friction driving wheel arranged with its periphery in contact with said outer face, a spindle, means driving said spindle at a uniform speed related to the speed of the knitting machine, the hub of the driving Wheel keyed to but slidable axially along said driven spindle, a manually adjustable screw provided for effecting the axial movement of the driving wheel hub, said driving wheel hub having a circumferential groove therein, a nut arranged to cooperate with said screw, and an element projecting from said nut and engaged in said groove.

2. In a knitting machine, a yarn feeding mechanism according to claim 1 having a bracket carrying the said mechanism, wherein said spindle driving means includes a pinion secured to said spindle and a rotary gear member meshing with said pinion and driven at a uniform speed from the knitting machine, said bracket being movable upon a support in such a manner as to enable interchanging said pinion on said driven spindle with another pinion having a different number of teeth so as to provide a different range of drum speeds.

3. A yarn feeding mechanism according to claim 1 having a spindle around which said carrier is arranged to revolve and an abutment provided on said spindle, wherein said carrier is loaded axially by a spring interposed between it and said abutment suchwise as to maintain the plain outer face of said plain-outer-faced member in contact with the friction driving wheel.

4. A yarn feeding mechanism according to claim 1, wherein the slip-resisting material covering said drum is a silicone rubber.

5. Ayarn feeding mechanism according to claim 1,. including a main bracket, aligned bearings in said bracket on which the driven spindle is mounted to rotate, a supplementa'ry bracket attached to said main bracket, and a pair of straight parallel bars mounted upon said supple-- mentary bracket, said bars having set therein rows of yarn guides in the form of apertured elements and being adjustable towards and away from one another in directions perpendicular to their length.

References Cited in the file of this patent UNITED STATES PATENTS