GB2202868A - Pattern selecting mechanisms for circular knitting machines - Google Patents

Abstract

An adjustable pattern key device for use in imposing a predetermined pattern upon pattern selecting blades (20) mounted in a bank or banks thereof in a circular knitting machine comprises a main body portion capable of being positioned in a readily removable manner adjacent a bank or banks of said blades (20), said body portion supporting a column of setting plates (8) each plate (8) adapted for sliding movement with respect to the body portion between a retracted position and at least one projected position in which an end portion of the plate (8) acts on the associated blade (20), and means (14) releasably to secure the plates (8) in their selected positions. The plates (8) preferably have three possible positions for a three-way selection by way of cams (22,24) actuated by the blades (20) and they may be set up by a unit with computer-controlled solenoids. <IMAGE>

Description

Pattern selecting mechanisms for circular knitting machines The invention is concerned with improvements in or relating to pattern selecting mechanisms for circular knitting machines.

In the production of jacquard fabrics, selecting means are required whereby to select appropriate needles in the needle cylinder for operation in accordance with the desired pattern, that is, a visible pattern formed by knit, tuck or miss stitches. The selecting means normally act, not directly upon the needles, but upon needle jacks or pattern jacks, separate cam tracks being required for the needles and for the jacks. The jacks are received in the lower portions of long tricks or slots formed in the cylinder.

The jacks are each provided with a raising butt, a lowering butt and at least one patterning butt. In each group of jacks, corresponding to the pattern repeat width which may comprise upto thirty six wales, each jack has its patterning butt at a different position or height for selective contact by the selecting means which is conventionally a plurality of sliding blades arranged in two banks at each yarn feed point of a multi-feed machine.

Projection of individual, pre-set blades from each bank causes the contact with appropriate pattern jacks to determine whether the associated needles miss, tuck or clear (knit).

In an example of such an arrangement, the blade at a given level in one bank is projected to cause the needle to tuck, the corresponding blade at the same level in the other bank being also projected alongside the first blade to cause the needle to miss. If neither blade at that level is projected, then the needle will clear.

It has become desirable in recent years to produce a greater variety in the patterning of jacquard fabric and this has resulted in the need for more frequent changes of pattern and a requirement for more versatility of pattern within a knitting operation.

Hitherto a number of pattern selecting mechanisms have been in common use. These range from pattern drums to individual combs, the former having a plurality of pairs of columns of pins or combs which project in an arrangement according to the desired pattern, the combs having breakable teeth or "bits" which are removed to form the appropriate arrangement. The mechanism is placed against the two banks of slidable patterning blades which when the appropriate blades are extended contact pattern jacks as mentioned above.

Pattern combs are usable once only,in the sense that the broken bits cannot be restored to provide a change in the pattern and therefore it is necessary to discard used combs and take fresh ones. This can often be costly and the removal of bits tedious and error-prone. Moreover there may be storage problems associated with a large number of "broken-out" combs.

Pattern drums may contain, say, four pairs of columns and inlay rotate to provide four changes of pattern, but the resetting of perhaps thirty six pins in each column on drums located one at each of say eighty four yarn feed points in a multi-feed machine, is a laborious and time-consuming task. Moreover, the use of drums is usually practical only with a knitting machine having no more than about forty eight feeds with pattern interchange in a sequential order, not at random choice.

It is an object of the invention to provide an improved pattern selecting mechanism offering increased versatility and range of patterning options on a multi-feed circular knitting machine.

The invention provides, in one of its several aspects, an adjustable pattern key device for use in imposing a predetermined pattern upon pattern selecting blades mounted in a bank or banks thereof in a circular knitting machine, said device comprising a main body portion capable of being positioned in a readily removable manner adjacent a bank or banks of said blades, said body portion supporting a column of setting plates, each plate adapted for sliding movement with respect to the body portion between a retracted position and at least one position in which an end portion of the plate projects with respect to the body portion and means releasably to secure the plates in one of the positions according to the predetermined pattern to be imposed upon the slidable blades.

The invention provides, in accordance with another of its several aspects, a method of imposing a predetermined pattern upon a bank or banks of slidable pattern selecting blades in a circular knitting machine comprising the steps of establishing a master pattern information source, submitting to said source a plurality of pattern key devices as described in the preceding paragraph, securing the plates thereof in positions determined by the information source and inserting the set-up key devices adjacent said bank or banks of slidable blades to impose the desired pattern thereon.

Preferably, the master pattern information source may be computer controlled. In an example a plurality of solenoids in a prograinmer unit are selectively energised to bring about movement of appropriate ones of said plates into a projecting position according to the master pattern.

The above mentioned method and device in accordance with the invention may readily be used with conventional banks of slidable pattern selecting blades comprising a plurality of pairs of side-by-side banks each pair arrangeable at a yarn feed point of the machine.

In our co-pending application no. 8701887 there is described a patterning mechanism comprising a single bank of superimposed patterning blades, each blade carrying a first camming surface and being associated through a rotatable member with a pivotable member bearing a second camming surface. Each blade is capable of taking one of three positions, fully retracted, partly extended and fully extended, corresponding to a selection of "clear", "tuck" and "miss" respectively.

The invention therefore provides in another of its several features, an adjustable pattern key device as mentioned above in accordance with the invention, wherein each plate is adapted for sliding movement between a retracted position, a first extended position in which the end portion of the plate projects with respect to the body portion hy a first pre-set distance and a second extended position in which the end portion projects by a second, longer, pre-set distance.

Conveniently the means releasably to secure the plates in one of the positions comprising a locking pin passing through one of two or three apertures in each of the plates, appropriate ones of said apertures being in alignment according to the desired positions of the plates.

Advantageously, two key devices according to the invention may be arranged side-by-side adjacent the single blades bank of the patterning mechanism as described in our co-pending application, each device having been subjected to a different pattern arrangement in a programmer unit.

In this way, one or the other or both or neither devices may be selectively applied to operate the single blades in a permutation of positions, thereby increasing the potential versatility of the patterning selecion.

There will now be described an example of an adjustable pattern key device according to the invention. It will be understood that the description which is to be read with reference to the drawings is given by way of example only and not by way of limitation.

In the drawings: Figure 1 is a side elevational view of a key device according to the invention; Figures 2, 3 and 4 are cross-sectional views taken on line III-III of Figure 1 showing plates thereof in three operating positions respectively; Figure 5 shows a plan view of a bank of single blades of a patterning mechanism; and Figures 6 to 11 are diagrammatic plan views of a key device in association with the single-blade bank patterning mechanism of Figure 5 and shown in six alternative operating and non-operating positions: and Figure 12 is a fragmentary view corresponding to Figure 8 but showing two columns of plates arranged side by side.

The device illustrated in the Figures comprises a main body portion 2 having a retaining bar 4 defining an elongate slot 6 within which are mounted for sliding movement a plurality, in the present example thirty nine, of setting plates 8.

The bar 4 is mounted to span the length of the slot 6 between two end pieces 10. Each end piece 10 has an aperture 12 through which passes a rod 14.

Each plate 8 is provided with three apertures 16 the purpose of which will be explained below.

The plates 8 comprise a column as shown in Figure 1. The provision for sliding movement allows each plate 8 to take up any one of three pre-determined positions within the slot 6, these positions being shown in Figures 2-4 respectively.

The first position shown in Figure 2 is regarded in the present example as the retracted position (clear). The second position (tuck) is an extended position in which an end portion 18 of the plate projects a short distance from the body portion 2.

The third position is shown in Figure 4 in a second extended position (miss)in which the end portion 18 projects a longer distance from the body portion 2.

The various positions are imposed upon the plates 8 by means of a programming step comprising subjecting the column of plates, which are in a freely slidably condition at this stage, to a unit including a solenoid or series of solenoids energised or non-energised in a computer-controlled pattern. In the example, all the plates are first moved to the central position shown in Figure 3, corresponding to the first extended position mentioned above. The action of the solenoid or solenoids is arranged to move selected ones of the plates by a distance x to the left, ( Figure 2 retracted position) or by the same distance to the right (Figure 4 second extended position), Figure 4 giving a distance 2x between the retracted and second extended positions.When the positions have been established, the plates are locked in their individual positions by passing the rod 14 through the apertures 12, 16, 12. It is necessary for the rod 14 to remain undeflected or undistorted in use to maintain the plates accurately in their exact position. To prevent any risk of the rod bending, strengthening means 15 are provided as shown in Figure 1.

Release of the plates is achieved by removing the rod, the plates being withdrawn from their extended position and easily re-set into a different combination of positions by re-submission to the programmer unit.

It will be understood that, if desired, the plates 8 may be re-set by hand. However, by using the programmer unit as in the present example, instead of the laborious task of re-setting pins in a pattern drurn or breaking teeth from a pattern comb, fresh patterns may he set up with the minimum of time and labour. In addition, there are economic advantages in employing a re-usable pattern key device in contrast with replacement of throw-away combs. Moreover, the pattern informative may conveniently be stored on for example, floppy discs or cassettes, thus taking up minimal storage space.

Figure 5 of the drawings illustrates patterning mechanism of the kind described in brief here and more fully in the co-pending patent application.

The mechanism comprises a single bank of thirty nine slidable pattern blades 20, each one arranged level with a corresponding one of the plates 8, for operation thereby.

As explained, in order for a patterning mechanism to operate to control the individual needles of a knitting machine, the mechanism must select one of three positions, miss, tuck and knit (clear). In a conventional pattern selecting device there are two banks of sliding blades each having a cam surface provided thereon the first being known as the "tuck" cam and the second the "miss" cam. When both blades of a pair (one from each bank) are retracted, both cams are out of action and the needle will knit. When only the tuck cam is extended, the result is a tuck stitch and when the miss cam is extended also, the result is a miss.

In the present example, the miss cam is provided as a surface 22 on the sliding blade 20 and the tuck cam is provided as a surface 24 upon an extension portion of a pivotal member 26 arranged for controlled, limited pivotal movement about a first fixed axis 28. The retraction and extension of the tuck cam surface 24 on the member 26 is controlled by the movement of a rotary member 30 about a second fixed axis 32. The member 30 is provided at one peripheral edge portion thereof with gear teeth 34 which mesh with similar teeth 36 provided in rack formation on a longitudinal edge of the blade 20. Thus, when the blade is extended, its lengthwise movement causes the member 30 to rotate about the axis 32.

It will be apparent that, where the plates are not in their extended positions the blades will remain in a position to cause the associated needle to knit. Where any plates are in their first extended position, i.e. extended by the distance x, each blade associated with such a plate will be advanced so that the cam surface 24 is projected beyond the operation line OL and the needle will tuck.

Where any of the plates are in their second, fully extended position, i.e. extended by the distance 2x, each blades associated with a fully extended plate will be advanced by distance 2x so that the cam surface 22 is also projected beyond the line OL and the needle will miss. In the present example the value of x is 3mm. In use, the column of plates 8 will be preset in the desired pattern and loaded into a knitting machine into an out-of-the way inoperative position in which the plates are clear of the blades 20 and all the needles knit. In the Figures, where x is 3mm, the plates 8 in the retracted position as shown in Figure 6 havo a distance of 6.5mm between them and the blades 20. In Figure 7 the distance is 3.5mm and in Figure 8 the distance is 0.5mm.

When the column of plates 8 is moved bodily frorn its inoperative position to an operative position, the blade of Figure 6 is shown in Figure 9 as corning only into abutting contact with the blade 20 but not causing any movement thereof so that the associated needle knits. It will be appreciated that the bodily movement is over a distance of 6.5mm, so that the plate 8 of Figure 7 (clearance distance 3.5mm) impinges on the blade 20 to move it 3mm (x) to the right as in Figure 10 and the associated needle tucks.

Similarly, the plates 8 of Figure 8 in moving 6.5mm, takes up the clearance distance of 0.5mm and then causes the blade 20 to move 6mm (2x)to the right and the associated needle misses.

The operation of the blades 20 may be controlled by either one column of plates 8 or if preferred by two columns arranged side-by-side as shown in Figure 12. Thus control by the key devices of the invention allows a greatly increased level of versatility without a corresponding increase in space occupied in the machine or in time and labour expenditure.

Various modifications may be made within the scope of the invention.

Claims (10)

1. An adjustable pattern key device for use in imposing a predetermined pattern upon pattern selecting blades mounted in a bank or banks thereof in a circular knitting machine, said device comprising a main body portion capable of being positioned in a readily removable manner adjacent a bank or banks of said blades, said body portion supporting a column of setting plates, each plate adapted for sliding movement with respect to the body portion between a retracted position and at least one position in which an end portion of the plate projects with respect to the body portion and means releasably to secure the plates in one of the positions according to the predetermined pattern to be imposed upon the slidable blades.

2. An adjustable pattern key device as claimed in claim 1, wherein each plate is adapted for sliding movement between a retracted position, a first extended position in which the end portion of the plate projects with respect to the body portion by a first pre-set distance and a second extended position in which the end portion projects by a second, longer, pre-set distance.

3. An adjustable pattern key as claimed in claim 1 or 2, wherein one of the positions comprises a locking pin passing through one of two or three apertures in each of the plates, appropriate ones of said apertures being in alignment according to the desired positions of the plates.

4. A patterning mechanism comprising a single bank of superimposed patterning blades, each blade carrying a first camming surface and being associated through a rotatable member with a pivotable member bearing a second camming surface, a pair of adjustable key devices as defined in any preceeding claim being provided in side-by-side arrangement adjacent said single bank of blades, each of said devices having a different pattern arrangement thereon.

5. A method of imposing a predetermined pattern upon a bank or banks of slidable pattern selecting blades in a circular knitting machine comprising the steps of establishing a master pattern information source, submitting to said source a plurality of pattern key devices as defined in any of claims 1-3, securing the plates thereof in positions determined by the information source and inserting the set-up key devices adjacent said bank or banks of slidable blades to impose the desired pattern thereon.

6. A method as claimed in claim 5, wherein the master pattern information source is computer controlled.

7. A method as claimed in claim 5 or 6, wherein solenoids in a programmer unit are selectively energised to bring about movement of appropriate ones of said plates into a projecting pattern according to the master pattern.

8. An adjustable pattern key device which is substantially as herein described in relation to the accompanying drawings.

9. A pattern mechanism which is-substantially as herein described in relation to the accompanying drawings.

10. A method of imposing a predetermined pattern upon pattern selecting blades which is substantially as herein described