GB1588576A

GB1588576A - Knitting machines

Info

Publication number: GB1588576A
Application number: GB19272/78A
Authority: GB
Original assignee: SCHAFFHAUSER STRICKMASCHF
Current assignee: SCHAFFHAUSER STRICKMASCHF
Priority date: 1977-05-13
Filing date: 1978-05-12
Publication date: 1981-04-23
Also published as: DE2726720C3; FR2390528B1; CH620954A5; DE2726720A1; JPS5418948A; ES469861A1; IT1094637B; DE2726720B2; IT7823361A0; JPS5754577B2; FR2390528A1

Abstract

To displace the sinkers, for example of a circular knitting machine, during the loop-forming operation, there is fastened to the stationary sinker ring (7) a toothed rim (11), with which meshes a pinion (12) of a two-stage angular gear (13) connected to a feed wheel (19). The feed wheel, having take-up bosses (20), performs the function of a wedge-shaped cam part for displacing the sinkers (21', 21'', 21'''), of which one sinker (21') is located at the start of the loop-forming depth and the other sinkers (21'', 21''') have assumed half the loop-forming depth and the entire loop-forming depth respectively. By means of the feed wheel (19), extremely large loop-forming angles can be achieved without appreciable wear of the parts connected to the loop-forming mechanism, so that complete individual loop-forming can be achieved, even where high finenesses and large stitch lengths are concerned. <IMAGE>

Description

(54) KNITTING MACHINES (71) We, SCHAFFHAUSER STRICK MASCHINENFABRIK, a Swiss body corporate of Schaffhausen, Switzerland, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to a device on a knitting machine which serves to displace the needles or sinkers used for stitch formation.

In knitting machines, carrying out the draw motion, i.e. the deformation of the thread supplied with the object of forming the stitch, is carried out with the aid of needles and sinkers which are displaced in a particular sequence. In known machines of this type, the displacement of the needles and sinkers is effected by wedge-shaped cam parts. Because of the friction of the needles and sinkers in their guides which cannot be avoided, the angle of the cam parts can however not be increased to any level; in known high speed machines it lies at about 53 to 57 angular degrees. Such angular values are however insufficient for a single draw motion of the thread, as is necessary in particular for slush knitting machines.In known circular knitting machines, e.g. in the French sinker wheel machine, the individual draw motion is achieved by a corresponding arrangement of the stitch forming elements in that with the aid of a lever action, greater draw motion angles can be achieved. However, it cannot be avoided by these measures that the cam parts and also parts which are connected to the sinker mechanisms such as needles, sinkers and their guide channels are subjected to heavy wear, which has as a result more adjustment work, greater maintenance costs and larger drive power requirements.

A circular knitting machine is further known (U.S. Patent Specification 3 690 124) in which it is attempted to diminish the frictional forces arising at steep cam angles in that the cam parts are brought into contact with vibration transducers for generating high frequency viblration running in a plane perpendicular to the butt of the needles, which generate a relative movement between the needles and the cam parts. The improvement thereby obtainable is however small and it additionally requires a comparatively high outlay.

Further a knitting machine is known (British Patent Specification 1 416291) in which for achieving a steeper displacement angle the needle is moved by means of a pretensioned spring. The - spring receives via a relatively fiat cam part a pretensioning, which after freeing of the needle brings the same with greater acceleration into the shifting position.

However also with this solution it is not possible to achieve the individual draw motion, particularly in plush knitting machines; this is because the displacement angle is dependent upon the easy movability or contamination of the needles, on the peripheral speed of the cylinder, on the material to be worked as well as on the stitch density. Since the needle feed does not take place automatically, the factors noted influence the feed angle which can be achieved.

The object underlying the invention is so to construct a device of the initially described type that extremely large draw motion angles can be achieved without subjecting the parts connected with the draw motion to high wear.

According to the present invention there is provided a knitting machine including means for displacing the needles or sinkers used for forming the stitches, comprising a feed wheel for operating the needles and/or sinkers to effect knitting, wherein the feed wheel is provided with at least one carrier stud which, on rotation of the feed wheel, displaces the sinker or the needle, the axis of rotation of the feed wheel forming an acute angle to the plane normal to the direction of movement of the sinker or needle, and means to rotate the feed wheel, synchronised with the machine speed, and at a speed determined corresponding to the machine fineness and the number of carrier studs.

By means of this it is achieved that the threads can be individually subjected to a draw motion by the stitch forming elements i.e. sinkers and needles since by means of the feed wheel according to the invention the sinkers or needles can be advanced or pulled back at a very steep angle, without the ideal conditions changing, that is a complete individual draw movement even with large fineness and extreme stitch lengths.

The invention is illustrated in the drawing with respect to two exemplary embodiments described below. In the drawing: Figure 1 is a vertical section through a circular knitting machine schematically and partially illustrated having bearded needles and taken along the line I-I in Figure 2; Figure 2 is a plan of the section illustrated in Figure 1 of a circular knitting machine with the sinker cam ring removed; Figure 3 is a vertical section through a schematic and partially illustrated circular knitting machine with latch needles along the lines III~III Figure 4, and Figure 4 is a side view of the section of the circular knitting machine according to Figure 3 with the cylinder cam set removed.

In Figures 1 and 2 there is illustrated by 1 a cylinder of a circular knitting machine at the vertical outer periphery of which bearded needles 2 are slidably mounted in guides 3. The displacement movement of the needles 2 takes place by means of cam parts 4 between which the butt 5 of the needles is guided. The cam parts 4 are fixed to a stationary cylinder cam fixture 6.

The cylinder 1 is connected with a sinker ring 7. The connection takes place via noses on non-illustrated bars which are fixed to the cylinder and which form the guide grooves for the needles. On these noses 8 the sinker ring 7 is centered by means of the aperture 9 and connected firmly with the cylinder 1 from below with the aid of clamping pieces 10. Fixed on the underside of the sinker ring 7 is a toothed ring 11 which meshes with a pinion 12 of a gear 13 which consists of a first bevel gear 14, 15 and a second bevel gear 16, 17. The pinion 17 is set on a shaft 18 which carries a feed wheel 19 which on its front face has four carrier studs 20 evenly distributed around its periphery.

The feed wheel 19 is, as is evident from Figure 2, arranged at a steep angle to the peripheral direction and takes over the function of a wedge-shaped cam part for displacing the sinkers 21 which are arranged horizontally and radially on the sinker ring 7.

Outside of the draw motion, the sinkers are guided by means of cam parts 22, 23, which are fixed to a sinker cam ring 24 arranged over the sinkers 21. For the draw motion, there is the feed wheel 19 and a draw counter guide 25 which is fixed together with the feed wheel 19 on a draw motion slide 26. The draw motion slide 26 is arranged radially movably on the sinker cam ring 24 so that the draw motion depth can be adjusted in common fashion by an adjusting screw not illustrated. In this connection note should be taken of the fact that gear 13 is so set that adjustment of the draw motion slide 26 does not bring any change relative to the engagement of these teeth.

In Figure 1 the sinker 21' is located directly at the moment of its taking over by the feed wheel 19. The sinker 21" has traversed half the displacement path, while the sinker 21' has taken up the draw motion depth set and in this position is guided by the draw motion counterguides 25. The cam part 23 is the return adjustment part on the wedge-shaped surface of which the sinkers 21 are pushed back again into their starting position.

In Figures 1 and 2 a thread guide 27 is illustrated still in dotted lines. On the other hand the presser bar for pressing the bearded needles together has been left out for clarity of illustration.

In Figures 3 and 4 the application of the feed wheel 19 to a circular knitting machine is shown. On the outer periphery of a cylinder 31 with a vertical axis there are arranged latch needles 32 movable in the vertical direction. The needles 32 have needle butts 33 by means of which they can be guided by cam parts 34, 35 outside of the draw motion and clearing motions. The cam parts 34, 35, of which cam part 35 is a clearing cam part, are fixed to a fixed position cylinder cam fixture.

The draw motion counterguide 37 and the drive provided for the drive of the feed wheel 19 are fixed on a draw motion slide 39 which on its part is mounted in fashion not shown on the cylinder cam fixture 36 and by displacement of which the depths to which the needles sink can be adjusted.

The gear 3!8 is composed of a toothed belt 40 which runs synchronously around the cylinder 31, a toothed belt pinion 41 and a screw gear 42, 43. The feed wheel 19 is fixed on the shaft 44 of the screw gear 43, which is arranged at a steep angle a to the peripheral direction of the machine.

From Figure 3 it is evident that the latch needles 32 have at their lower end a draw motion foot 45, on which the carrier studs 20 engage. The draw motion foot 45 is located in the out of action position and is moved downwards by the carrier stud. The draw motion feet 45' and 45" of two further latch needles are illustrated in the middle position and in the end position respectively (draw depth).

The cylinder 31 is connected by means of noses 46 of cylinder posts not illustrated in more detail with a sinker ring 47 and is fixed at its underside by means of the clamping pieces 48. In the sinker ring 47 knockover sinkers 49 are arranged in radial and horizontal position, which are moved by cam parts 50.

The cam parts 50 are fixed on the underside of a fixed position sinker cam ring 51.

In Figure 3 a thread guide 52 is illustrated.

The device described makes possible the achievement of larger draw motion angles e.g.

of the order of 78 to 820. Despite this, the displacement conditions can pe characterised as ideal. At the moment of take-over of the sinkers 21 or of the needles 32 by the feed wheel 19, the feed movement in the feed direction is zero and it then rises sinusoidally to a maximum and then falls correspondingly again to zero. At this position the sinkers 21 or the needles 32 are taken over by the draw motion counterguide 25 or 37 to equalise the draw motion depth. Then the return position part 23 or 25 displaces the sinkers 21 or needles 32 back again into their starting position.

The number of carrier studs 20 of the feed wheel 19 has no influence on the principal function of the device and can be matched to the particular circumstances. The dimensioning and drive ratios of the device are dependent upon the machine data e.g. machine diameter, fineness, maximum draw motion depth and the measurements of the stitch forming elements and can be constructed correspondingly. The use of the device described can also take place on machines with rectilinear carriers for the stitch forming elements, e.g. straight bar knitting machines, Cotton machines or the like.

Likewise the sensible application of the device to needle or sinker movement in the opposite direction, not shown in the drawings, is possible. Also the application of the device described to both carriers of the stitch forming elements simultaneously is possible, by means of which further combinations of the device described arise.

WHAT WE CLAIM IS: 1. A knitting machine including means for displacing the needles or sinkers used for forming the stitches, comprising a feed wheel for operating the needles and/or sinkers to effect knitting, wherein the feed wheel is provided with at least one carrier stud which, on rotation of the feed wheel, displaces the sinker or the needle, the axis of rotation of the feed wheel forming an acute angle to the plane normal to the direction of movement of the sinker or needle, and means to rotate the feed wheel, synchronised with the machine speed, and at a speed determined corresponding to the machine fineness and the number of carrier studs.

2. A knitting machine according to claim 1 wherein the feed wheel is rotatably mounted on a cam part carrier.

3. A knitting machine according to claim 1 wherein the feed wheel and a draw motion counterguide are mounted on a draw motion part carrier.

4. A knitting machine according to any one of claims 1 to 3 wherein the feed wheel is driven synchronously from a drive member connected with the needle or sinker carrier.

5. A knitting machine according to claim 4 wherein the drive member is a toothed ring, a toothed rod or a toothed belt.

6. A knitting machine with means for displacing the sinkers substantially as hereinbefore described with reference to Figures 1 and 2 of the accompanying drawings.

7. A knitting machine with means for displacing the needles substantially as hereinbefore described with reference to Figures 3 and 4 of the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. of the order of 78 to 820. Despite this, the displacement conditions can pe characterised as ideal. At the moment of take-over of the sinkers 21 or of the needles 32 by the feed wheel 19, the feed movement in the feed direction is zero and it then rises sinusoidally to a maximum and then falls correspondingly again to zero. At this position the sinkers 21 or the needles 32 are taken over by the draw motion counterguide 25 or 37 to equalise the draw motion depth. Then the return position part 23 or 25 displaces the sinkers 21 or needles 32 back again into their starting position. The number of carrier studs 20 of the feed wheel 19 has no influence on the principal function of the device and can be matched to the particular circumstances. The dimensioning and drive ratios of the device are dependent upon the machine data e.g. machine diameter, fineness, maximum draw motion depth and the measurements of the stitch forming elements and can be constructed correspondingly. The use of the device described can also take place on machines with rectilinear carriers for the stitch forming elements, e.g. straight bar knitting machines, Cotton machines or the like. Likewise the sensible application of the device to needle or sinker movement in the opposite direction, not shown in the drawings, is possible. Also the application of the device described to both carriers of the stitch forming elements simultaneously is possible, by means of which further combinations of the device described arise. WHAT WE CLAIM IS:

1. A knitting machine including means for displacing the needles or sinkers used for forming the stitches, comprising a feed wheel for operating the needles and/or sinkers to effect knitting, wherein the feed wheel is provided with at least one carrier stud which, on rotation of the feed wheel, displaces the sinker or the needle, the axis of rotation of the feed wheel forming an acute angle to the plane normal to the direction of movement of the sinker or needle, and means to rotate the feed wheel, synchronised with the machine speed, and at a speed determined corresponding to the machine fineness and the number of carrier studs.