GB2144153A - A structure-patterned knitted fabric and a knitting machine mechanism for its production - Google Patents

Abstract

By controlled adjustment of cam box parts 22 the needles 11 are influenced collectively whilst avoiding individual needle selection to produce pattern regions with varying stitch length. The formation of particular patterns is effected by the choice of the shape of cams 14', 15' on two or more cam carriers, 14, 15 which rotate relative to the cam-box carrier 21, by the choice of the direction of movement of these cam carriers 14, 15 relative to the needle cylinder 10, and by the choice of the ratio of the magnitude of movement of the carriers 14, 15 to that of the needle cylinder 10. In the latter respect, programme-controlled individual drive of the individual cam rings 14, 15 can be effected or they may be geared at 18 to the needle cylinder carrier 12. The pattern may take the form of stripes which can cross over, zig zag or have curved regions. <IMAGE>

Description

SPECIFICATION A structure-patterned knitted fabric and a knitting machines mechanism for its production This invention relates to a structure-patterned knitted fabric with stitches of different lengths as well as to a knitting machine mechanism for the production of such a structure-patterned knitted fabric.

One object of the invention is to provide a structure-patterned knitted fabric in which short stitches and long stitches do not occur only in fixedly preset stages and in regions which are correspondingly sharple defined from one another. Afurther object is to design a knitting machine in such a way that it can provide such a structure-patterned knitted fabric, whilst avoiding a customary Jacquard patterning mechanism, at full machine capacity, and in a form which is capable of modification but is reproducible.

The first object is achieved in accordance with the invention in that the knitted fabric is provided with patterning regions in which the length of the stitches changes from the region edge to the region centre or from one region edge to another region edge so that not only regions with uniformly short or with uniformly long stitches are present.

The structure patterning of the knitted fabric in accordance with the invention allows for a great deal of variation. Thus, for example, the stitch length of consecutive stitches can change progressively over entire stitch courses or stitch wales. Advantageously the patterning regions having stitches of different length are arranged between regions with uniformly short stitches and regions with uniformly long stitches, in which respect these patterning regions have a progressive transition of the stitch length between the two above-mentioned regions. Also the knitted fabric can have stitch courses with equally long stitches, between which there are stitch courses in which the stitch size changes along the length of the course.

In the knitted fabric fashions in accordance with the invention, the structure patterning can also be achieved by an alternation between tuck/stitch and back/stitch, such alternation again being effected in patterning regions or intermediate courses which lie between regions having uniform stitch pattern.

Particularly attractive structure patterns can be achieved in that regions with equally long stitches appear as longitudinal, transverse or oblique stripes or as curved paths in the fabric. The stripes, particularly the oblique stripes, can also intersect one another. A further possibility of variation is afforded in that the striped regions may have different widths and/or different spacings from one another.

Structure-patterned fabric in accordance with the invention can be obtained in a particularly advantageous manner using a knitting machine mechanism comprising cams for the collective control of the needles, which cams are moved relative to a machine cam box and bring about adjustment of the cam box parts controlling the needles, the cams being arranged exchangebly on at least one cam carrier which carries out, relative to a needle carrier and a cam box carrier, an adjustable but exactly determinable relative or absolute movement.

Adjustment of individual cam boxes parts of knitting machines by means of cams is already known. In this way, switching out and in of cam-box parts or a position change of a cam-box part can be varied, which also has an effect on the knitted fabric structure. Also, it is known in knitting machines to provide adjustable draw-off cam-box parts which determine the stitch length. With the known camcontrolled switching mechanisms for knitting machine cam-boxes flat two-dimensional knitting regions, (particularly regions consecutive in the longitudinal direction ofthe knitting,) having a different structure have been produced, but not genuine structure patterning with preset geometric figures. To date to achieve this individual needle selection has always been necessary.

In accordance with the invention, the cams may advantageously be arranged on at least two cam carriers which are selectively movable with the same or a different magnitude and/or direction. In this respect the cams of at laast one of the several cam carriers may be adjustable individually or jointly relative to the cams of another cam carrier.

The structure patterning achieved with a mechanism designed in accordance with the invention is thus dependent upon the relative speed of the control cams relative to the needle carrier or the machine cam boxes as well as upon the cam shape and the cam arrangement. A Jacquard mechanism with individual needle selection is abolished. The needles are controlled collectively such that the knitting machine can always be run at full machine capacity.

With the mechanism in accordance with the invention the needles can be influenced at any marked point of their movement curve. More espe ciallythe mechanism can be used for the adjustment of the draw-off cam-box parts during operation of the knitting machine, whereby a structure pattern in the fabric results through the formation of stitches of different lengths and the transition from a knitting region with a very small set stitch length to a knitting region with a maximum stitch length is gradual not sudden. The mechanism can, however, also be used to influence tuck cam-box parts or even for the simultaneous influencing of tuck cam-box parts and draw off cam-box parts. In each case the crossweaving structure of the knitting is influenced so as to produce a pattern.If, in this respect, fix ratio values of the relative speeds of the differently moving parts are chosen, uniform geometrical patterning figures result. It is, however, also possible in accordance with the invention to control the cam carriers with alternating movement ratios, e.g. by mean of programme-controlled stepping motors, whereby arbitrarily formed and non-uniform structure patterns which are however reproducible within a pattern repeat, can be achieved in a piece of knitting.

The invention can be applied in a particularly favourable manner to circular knitting machines. In the case of a circular knitting machine having a revolving needle carrier the cams on two cam rings arranged concentrically to the needle cylinder can be exchangeable and be so arranged that they are moved, for example by way of toothed-wheel change gear, synchronously or asynchronously with respect to the needle cylinder. In this respect, one of the cam rings is advantageously separated into a part carrying an exchangeable cam and a part having a drive toothing, the part carrying the cam being adjustable in the circumferential direction and securable relative to the other parts, and thus also relative to the other cam ring.

Thus, with a mechanism in accordance with the invention through stitch or loop structure changes various patterns can be achieved, for example longitudinal stripes patterns with uniformly or nonuniformly distributed stripes, obliquely extending stripes or even, in the case of cam carriers which are moved in the opposite direction to one another, cross-stripe patterns. The character of the strip structure will be partly dependent on the design of the cams which are advantageously mounted so as to be exchangeable. In this respect it is important to note that all these patterns are reproducible within the knitting region of a knitting machine even with respect to pattern angles.

The invention will be described further, by way of example, with reference to a structure patterning mechanism designed for a circular knitting machine and with reference to the accompanying drawings, in which: Figure 1 is a partial radial section through a single-knitting-headed circular knitting machine having a structure patterning mechanism in accordance with the invention; Figure 2 is a schematic partial diagram of the two cam rings of the structure patterning mechanism and a schematic representation of a structurepatterned piece of knitting; Figure 3 is a partial diagram of the cam rings corresponding to Figure 2 but with different structure patterning of the piece of knitting; Figures 4, 5 and 6 are schematic representations of exemplified embodiments of further possible structure patterns; and Figure 7 is a schematic stitch pattern representation of a knitted fabric with different structure pattern regions.

The partial radial section of Figure 1 shows a needle cylinder 10 of a single-knitting-headed circular knitting machine which is studded with latch needles 11. The needle cylinder 10 is fastened on a rotatably mounted cylinder carrier 12 which is provided with a toothed driving rim 13. Mounted rotatablyanovethetoothed rim 13 are two ram rings 14 and 15 which are in each case provided with exchangeable cams 14' and 15'. For driving the cam ring 14 is provided with a toothed rim 16 and the cam ring 15 is provided with a toothed rim 17. The toothed rim 17 is formed separately from the cam ring 15, so that the cam ring 15 can be rotated relative to the toothed rim 17 to vary the position of its cams 15' relative to the cams 14' of the other cam ring 14 after release of a coupling device (not shown).

The two cam rings 14 and 15 with their toothed rims 16 and 17 respectively are securely coupled, by way of a toothed gear wheel 18 having respective toothed wheels, with the toothed driving rim 13 of the cylinder carrier 12 and thus with the machine drive. The two cam rings 14 and 15 could alternatively be coupled with the machine drive in a freely selectable and non-rigid manner by way of separate motors and by way of a programmersynchronised with the machine drive.

At each system of the mu It-system circular knitting machine the cams 14' and 15' of the two cam rings 14 and 15 act on a slider 20 which is provided with a feeler roll 19, or alternatively on two or more such sliders. The slider 20 is mounted so as to be displaceable in the vertical direction on a stationary cam-box or lock ring 21 of the circular knitting machine. In the illustrated embodiment the slider 20 supports a draw-off cam-box or lock part 22 of a cam-box system which positively controls the latch needles 11 in both needle adjustment directions by way of an upper control butt 23 and a lower control butt 24. The slider 20 can be adjusted by the cams 14', 15' of both cam rings 14 and 15 against the force of a restoring spring 24.The position of the draw-off cam-box part 22 is thus adjusted when necessary to continuously cange the draw-off stretch and thereby control the length of the stitches formed. This adjustment is variable.

The draw-off cam-box part 22 is fastened on a part 20a of the slider which is connected to the slider part 20 carrying the feeler roll 19 by an adjusting screw 26 with a knurled adjusting head 27 which is accessible from the outside of the knitting head. One stop of the slider 20 is formed by the feeler roll 19. Another stop is formed by an eccentric pin 28 which engages laterally into the slider 20 and which is fashioned on a rotatably mounted stroke limiting body 29 which is also accessible from the outside of the knitting head.

By rotating the stroke limiting body 29, which is provided in a manner which is not shown with a scale, the slider 20 can be lifted off to a greater or lesser extent from the path of revolution of the cams 14' and 15'. Indeed it can be lifted offto such an extent that the cams 14' and 15' can no longer touch the feeler roll 19.

The basic setting of the draw-off cam-box part 22 fastened to the slider part 20a is effected in stepless manner by way of the adjusting screw 26 with the knurled adjusting head 27. This fixes the minimum draw-off position necessary for the smallest stitch length. The difference between the longest producible stitches and these smallest stitches is then set by means of the stroke limiting body 29.

Figure 2 shows one above the other a partial diagram of the two cam rings 14 and 15 with the cams 14' and 15' which are screwed onto them so as to be exchangeable. in the illustrated embodiment, the cams 14' and 15' have the same shape. This is not always the case, however. The cams 14' and 15' are constructed symmetrically and include portions 30 which rise obliquely towards both ends and between which there lie horizontally extending portions 31 which form the highest cam prominences.

The length of each horizontal portion 31 is a multiple of the needle graduation step of the needle cylinder 10. This highest cam portions 31 give rise to the formation of small stitches, in other words, in the structure-patterned piece of knitting 32 shown schematically in Figure 2, to a stripe 33 consisting of small stitches, the width of these stripes depends upon the length of the horizontal cam portions 31. As a result of the oblique cam portions 30, a shifting of the draw-off cam-box part 22 is brought about, which means the formation of stitches which become increasingly larger if one considers an adjustment from the highest cam portion 31. The cams 15' are, however, offset relative to the identically formed cams 14' of the cam ring 14 by half of a cam length.

This means that the feeler roll 19 of the slider 20, even upon an appropriate setting of the stoke limiting body 29, cannot actualy reach the lowest cam locations 34. On the contrary, a feeler roll 19 running off from the upper cam portion 31 on an oblique portion 30 of a cam 14' soon arrives on the oppositely inclined oblique portion 30 of an offset cam 15' which raises the feeler roll 19 onto the upper horizontal portion 31 of the cam 15' and thereby compels the formation of a second stripe of small stitches. Between the stripes 33 of the piece of knitting 32, therefore, there extend regions 35 in which the stitch size increases as far as the centre of these regions and then decreases again until the next stripe 33 is reached.Through an adjustment of the stroke limiting body 29, however, the feeler roll 19 can be prevented from running down as far as the point of intersection of the two portions 30, so that in the centre of the region a panel with stitches of the same length, namely of a set limiting length, can arise.

Figure 2 shows a piece of knitting 32 having a vertically striped pattern. Such a vertically striped pattern emerges when the two cam rings 14 and 15 are driven synchronously with the needle cylinder 10. The width of the strips 33 and 35 are determined by the shape of the cams 14' and 15' used. Whether the stripe sequence is regular or irregular depends upon how far the cams 15' of the adjustable cam ring 15 are offset relative to the cams 14' of the cam ring 14.

Figure 3 show schematically the structure of a piece of knitting 36 which results when the cam rings 14 and 15, which are provided in exactly the same way as in Figure 2 with equal and mutually offset cams 14' and 15', are moved with the same speed but in the opposite direction to one another.

Through this opposed movement the stripes 33' brought about by the highest cam portions 31 and thus consisting of short stitches occur in a regular diamond pattern, whilst the knitting regions 35' lying therebetween, which are no longer in the form of stripes, have stitches the length of which becomes continuously largerfromthe edges of the regions 33' to the centre of the regions 35'.

The two pieces of knitting 32 and 36 shown schematically in Figures 2 and 3 already indicate a large number of patterning possibilities and also the fixedly preset and thus reproducible shape of patterns which can be achieved by appropriate choice of the shape of the cams 14',15', of the degree to which the cam 14' of the one cam ring 14 is offset relative to the cam 15' of the other cam ring 15 or vice versa, and of the direction of revolution of the two cam rings 14 and 15 if a constant speed ratio to the needle cylinder is given to the two cam rings 14 and 15. In this respect Figure 5 shows schematically a further example of a knitting pattern 37 which possesses stripe regions 38 which intersect one another at an acute angle.Further patterning possibilities arise through the removal or switching off of individual cams and the switing-away of sliders 20 of individual knitting systems.

The multiplicity of the patterning possibilities can, however, be increased still further if the speed ratio between the cam rings 14, 15 and the needle cylinder 10 is changed during the knitting operation. Figure 4 shows schematically a striped zig-zag pattern of knitting 39, which can be achieved by changing the speed ratio by means of a toothed-wheel changeover gear, the zig-zag stripes indicated by reference numeral 40. The knitting structure patterning is, however, not limited to rectilinear stripes. If the cam rings 14 and 15, as has already been mentioned, are driven by means of programme-controlled stepping motors, patterns with curved stripes 41 can be achieved, as illustrated in the structure-patterned piece of knitting 42 shown schematically in Figure 6.

Afurther increase in the structure-patterning possibilities is achieved if two or more sliders per system are adjusted by cam carriers and in so doing at two different locations of the so-called needle curve the needles of the knitting machine are influenced. For example, an adjustment of the draw-off cam-box parts and of cam-box parts controlling the needles in the tuck region could be undertaken at the same time. The mechanism of the invention is not restricted to circular knitting machines and can be used in flat knitting machines with a correspondingly different construction of the machine carriage.

The schematic Figure 7 is intended to impart an impression of the actual thread course in the structure-patterned knitted fabric. Figure 7 shows two stitch courses 43,44 having regions with long stitches and regions with short stitches as well as with regions, lying therebetween, with alternating stitch length. Bounded by dot-dash lines are stitch course regions A, B, C, D and E. In the stitch course regions A and E the stitch course 43 has uniformly short stitches 45 and the stitch course 44 uniformly long stiches 46. In the stitch course region C it is vice versa. There the stitch course 43 has uniformly long stitches 46 and the stitch course 44 has uniformly short stitches 45. The stitch course regions B and D form transitional regions in which the stitch length in the two stitch courses 43 and 44 changes continuously. In the stitch course region B the stitches 47 of the stitch course 43 are successively enlarged from the length of the short stitches 45 of the stitch course region A up to the length of the long stitches 46 of the stitch course region C, whilst conversely the stitches 48 of the stitch course 44 become successively smaller from the length of the long stitches 46 to the length of the short stitches 45. In the transitional region D the reverse alternation then takes place. The stitches 49 of the stitch course 43 shorten successively from the region boundary 51 to the region boundary 52, whilst the stitches 50 of the stitch course 44 become increasingly longer from the region boundary 51 to the region boundary 52.

The stitch course 53 linking underneath and shown only partially can have altogether equally long stitches 54 and belong to an unpatterned transverse stripe of the knitted fabric.

Claims (22)

1. A structure-patterned knitted fabric having stitches of different lengths, characterised by patterning regions in which the length of the stitches changes from the region edge to the region centre or from one region edge to another region edge.

2. A knitted fabric as claimed in claim 1, characterised in that the stitch length of consecutive stitches changes progressively over entire stitch courses or stitch wales.

3. A knitted fabric as claimed in claim 1 or 2, characterised in that it includes regions with uniformly short stitches, regions with uniformly long stitches, and regions lying therebetween having a progressive transition of the stitch length between the two above-mentioned regions.

4. A knitted fabric as claimed in claim 1,2 or 3, characterised in that it has stitch courses with equally long stitches, between which there are stitch courses in which the stitch size changes along the stitch course length.

5. A knitted fabric as claimed in any preceding claim, characterised in that it has structure-patterned intermediate courses form by alternation between tuck/stitch and back/stitch.

6. A knitted fabric as claimed in any preceding claim, characterised in that its regions where equally long stitches appear as longitudinal, transverse or oblique stripes or as curved paths in the knitted fabric.

7. A knitted fabric as claimed in claim 6, characterised in that the stripes are oblique and intersect one another.

8. A knitted fabric as claimed in claim 6 or 7, characterised in that the striped regions have a different widths andlor different spacings from one another.

9. A knitting machinemechanismfortheproduc- tion of structure-patterned knitted fabric as claimed in any of claims 1 to 8, said mechanism cams comprising for the collective control of the needles, which cams are moved relative to a machine cam box and bring about adjustment of the cam box parts controlling the needles, the cams being arranged exchangeably on at least one cam carrier which carries out, relative to a needle carrier and a cam box carrier, an adjustable but exactly determinable relative or absolute movement.

10. A mechanism as claimed in claim 9, characterised in that the cam box parts which are adjustable by means of the cams positively control the needles in their expulsion movement and/or in the restoring movement.

11. A mechanism as claimed in claim 9 or 10, characterised in that the cams are arranged on at least two cam carriers which are selectively movable with the same or different magnitude and/or direction.

12. A mechanism as claimed in any of claims 9 to 11, characterised in that the cam of at least one of the cam carriers is adjustable relative to the cam of another cam carrier.

13. A mechanism as claimed in any of claims 9 to 12 for a circular knitting machine with a revolving needle carrier, characterised in that arranged concentrically to a needle cylinder are two cam rings which are coupled with a driving shaft for the needle cylinder by way of at least one toothed wheel gear.

14. A mechanism as claimed in claim 13, characterised in that one cam ring is separated into a part carrying an exchangeable cam and a part having a driving toothing, the part carrying the cam being adjustable in the circumferential direction and securable relative to the other part.

15. A mechanism as claimed in any of claims 9 to 14, characterised in that the movement of the cam carriers is effected by means of separate stepping motors, which are controlled as a function of the movement of the needle carrier or the cam box carrier.

16. A mechanism as claimed in claim 15, characterised in that the stepping motors are controllable by means of a programmer which is dependant upon the relative movement of the needle carrier.

17. A mechanism as claimed in any of claim 9 to 16, characterised in that the cams of all the cam carriers on each cam box system act by way of at least one lever or slider on at least one draw-off cam box part which determines the stitch length.

18. A mechanism as claimed in any of claims 9 to 16, characterised in that the cams of all the cam carriers on each cam-box system can act by way of at least one lever or slider on at least one cam-box part which determines the expulsion position (rest, tuck or knitting position) of a needle.

19. A mechanism as claimed in any of claims 9 to 18, characterised in that the cams have a top region which is aligned at their direction of movement and the length of which is a multiple of a graduation step of the needle carrierofthe knitting machine.

20. A mechanism as claimed in any of claims 9 to 19, characterised in that the cams and/or the switching members influenced by them are designed so that they can be individually disconnected into a rest position.

21. A structure-patterned knitted fabric substantially as hereinbefore described with reference to and as illustrated by Figure 2, or Figure 3, or Figure 4 or Figure 5, or Figure 6, or Figure 7 of the accompanying drawings.

22. A knitting machine mechanism for production of a structure-patterned knitted fabric as claimed in any of claims 1 to 8 substantially as hereinbefore described with reference to and as illustrated in Figure 1 and Figure 2 or Figure 3 of the accompanying drawings.