WO1999014412A1

WO1999014412A1 - An accessory for feeding yarn in a knitting machine

Info

Publication number: WO1999014412A1
Application number: PCT/GB1998/002844
Authority: WO
Inventors: Gary Paul Latham
Original assignee: Textured Jersey Uk Limited
Priority date: 1997-09-18
Filing date: 1998-09-18
Publication date: 1999-03-25
Also published as: GB9719791D0

Abstract

A device (40) to enable two yarns to be supplied separately to the feeder of a knitting machine is disclosed. The feeder is of the type in which each of the yarns is fed through an aperture (46) to a needle, and the device comprises an elongated housing (42) defining an enclosed path (44) extending between an exit aperture located at one end of the housing and adapted to be mounted in contact with an aperture (46) of the feeder and a second aperture located at the end of the housing remote from the exit aperture (48), for receiving yarn from a yarn store. The housing is preferably provided with a further aperture for the supply of compressed air (54) to the enclosed path, in order to simplify the rethreading of a needle when the yarn breaks. The device is particularly suitable or use when one of the two yarns which is being supplied to the feeder is a hard yarn such as a cotton yarn and the other is a resilient yarn such as a Lycra yarn.

Description

Title: An Accessory for Feeding Yarn in a Knitting Machine

The present invention relates to an accessory for feeding yam in a knitting machine, in particular but not exclusively, in a latch-hook knitting machine.

The accessory can be used on a circular machine such as a single or double jersey cylinder, 5 or a flat or v-bed machine.

Knitting machines are commonly used to produce knitted fabric in large quantities. A typical circular knitting machine includes a series of reciprocable needles which are furnished with yam by a series of feed systems having yam fed therethrough.

Certain fabrics incorporate two types of yam, one being a hard yam, such as cotton, viscose 0 or nylon, and the other being a resilient yam such as Lycra. It is hereby acknowledged that Lycra is a Registered Trade Mark.

In order to feed the two yams into the knit, commonly the feed system has been of a design such that the Lycra and the hard yam are fed so that they ran adjacently and then through separate apertures of a feeder to the needle. The Lycra and the hard yam are then plated so 5 that the resultant knitted fabric is of consistent appearance.

The feeder need not be of a unitary construction; a separate arm of the feeder may be provided for the Lycra, such that the Lycra is maintained on a path adjacent the path of the hard yam.

A feeder system as described above is illustrated in Figure 1 and will now be described by " . ) way of example of the prior art.

The feeder system 10 is one of a plurality of identical feed systems arranged in a radially spaced manner around a circular knitting machine of known type. The knitting machine comprises a plurality of radially spaced latch needles which are arranged to slide in corresponding tricks or grooves at the circumference of the needle cylinder. The cylinder is mounted for axial rotation about a substantially vertical axis.

5 Each needle has a butt arranged to engage with a cam or cams on the needle cylinder so as to reciprocate in the trick in a predetermined manner. Reciprocation of successive needles in their tricks is operative to produce a knitting action.

The feed system 10 has a vertically descending pillar portion 12, at the lower end of which is a feeder 14 which extends in a direction diagonally downwards and tangential of the 0 cylindrical trick.

A flange 16 extends from the pillar portion of the feed system 10. The flange 16 extends in a direction radially outwards of the trick. The flange 16 is generally L-shaped, having a horizontal portion 18 and a vertical portion 20. Two pot-eyes 22, 24 are situated in the horizontal portion 18, and one pot-eye is situated in the vertical portion 10. The pot-eyes 5 22, 24, 26 are provided for the passage of yam therethrough in a relatively frictionless manner.

At the end of the feeder 14 distal the pillar portion 12, there are two apertures 28, 30 extending, in a generally radial direction of the cylinder trick, through the feeder 14.

In use, and as shown in Figure 1, hard yam 32 such as cotton is fed from a creel (not shown)

') n via a storage unit (not shown) to the feed system 10 where it passes through one of the pot- eyes 22 and through one 28 of the apertures 28, 30 of the feeder 14. The yam 32 is fed through the aperture 28 in the direction towards the cylindrical trick and the needles engaged therein.

In use, Lycra yam 34 is fed from a cone mounted on an overhead rack (not shown) of the machine. The Lycra yam 34 is fed through the other 30 of the two apertures 28, 30 in the same direction as the cotton yam 32.

The two yams 32, 34 are fed to the needles where they are knitted together to form a plated fabric.

It is widely appreciated that the build up of lint in knitting machines is a serious problem which can result in reduced quality product, and may cause malfunction of the knitting machine. Accordingly, a blowing device or a suction device can be used to remove lint from the knitting environment of the machine. Alternatively, the entire mill in which the machine is situated can be humidified.

In operating a knitting machine of the type described above, it has been observed that the Lycra yam may be displaced accidentally by the building up of lint so that the Lycra yam makes contact with the hard yam. The Lycra yam has very high frictional properties and so if the Lycra yam makes contact with the hard yam, the Lycra yam can be dragged through the aperture through which the hard yam is fed. This results in the two yams being presented to the needles in an orientation which precludes plating. That is a quality control fault which can barely be perceived in the final fabric. The fault results in waste fabric.

It will be appreciated that displacement of the Lycra yam into the hard yam may be caused by other factors, such as collision into the Lycra yam by a person inspecting the operation of the machine.

Known knitting machines are provided with a trip mechanism to ensure that the knitting process is interrupted if one of the yams, more frequently the hard yam, breaks. The operator then has to re-thread the needle mechanically, which can be inconvenient and time consuming.

It is an object of the invention to reduce the possibility of incorrect plating of two yams as a result of faulty feeding of yam to the needles of a knitting machine.

It is a further object of the present invention to provide an improved method of re-threading a needle during the knitting process.

The present invention provides a device to enable two yams to be supplied separately to the feeder of a knitting machine, which feeder is of the type in which each of the yams is fed through an aperture to a needle, which device comprises an elongated housing defining an enclosed path extending between an exit aperture located at one end of the housing and adapted to be mounted in contact with an aperture of the feeder and a second aperture located at the end of the housing remote from the exit aperture, for receiving yam from a yam store.

In that way, yam along adjacent supply paths cannot be knocked into contact with each other.

The present invention further provides a feed system for feeding two yams to a knitting machine, wherein a device to enable two yams to be supplied separately to the feeder of a knitting machine, which feeder is of the type in which each of the yams is fed through an aperture to a needle, which device comprises an elongated housing defining an enclosed path extending between an exit aperture located at one end of the housing and adapted to be mounted in contact with an aperture of the feeder and a second aperture located at the end of the housing remote from the exit aperture, for receiving yam from a yam store is mounted on the feeder, on the side of the feeder remote from the needle.

The present invention further provides a method of feeding two yams separately to a knitting machine, wherein one of the yams is a hard yam and the other of the yams is a resilient yam, and the hard yam is supplied to the feeder through a device to enable two yams to be supplied separately to the feeder of a knitting machine, which feeder is of the type in which each of the yams is fed through an aperture to a needle, which device comprises an elongated housing defining an enclosed path extending between an exit aperture located at one end of the housing and adapted to be mounted in contact with an aperture of the feeder and a second aperture located at the end of the housing remote from the exit aperture, for receiving yam from a yam store.

In a preferred embodiment of the invention, the elongated housing comprises a tube through which one of the supply paths passes. The tube is particularly advantageous in that one of the supply paths is completely surrounded and shielded thereby.

The tube may be of transparent or translucent material In that way, the build up of lint within the tube may be monitored.

Preferably, the tube is of polytetrafluoroethylene (PTFE). In that way, the tube is not susceptible to distortion through heat.

In a particularly preferred embodiment of a device according to the invention, the elongated housing comprises a casting, which casting is preferably provided with a further aperture for the supply of compressed air to the enclosed path.

It will be appreciated that the present invention is not limited to devices which furnish only two yams; further supply paths can be provided on the feeder, with further barriers provided to separate the supply paths against the yams of the supply paths against the ya s of the supply paths coming into contact.

Further aspects and advantages of the invention will be apparent from the following description, by way of example, of a specific embodiment of apparatus in accordance with the invention with reference to the accompanying drawings, in which:

Figure 1 is a front elevation of a feed system illustrated as an example of the prior art;

Figure 2 is a front elevation of a feed system comprising a first embodiment of a device to enable two yams to be supplied to the feeder of a knitting machine; Figure 3 is a front elevation, partially in section, of an alternative embodiment of a device to enable two yams to be supplied to the feeder of a knitting machine.

Figure 1 illustrates a feed system which forms part of the state of the art. The feed system is described in the introduction above.

Figure 2 shows a feed system 110 of similar construction to the feed system 10 of Figure 1. In so far as certain features of the feed system of Figure 2 are identical with those of Figure 1, they are accorded the same reference numerals. Only those features of the feed system 110 of Figure 2 which are not present in the feed system 10 of Figure 1 will now be described.

A tube 36 of translucent PTFE material is mounted to extend between the pot-eye 22 through which cotton yam 32 passes in use and the aperture 28 in the feeder 14 through which the cotton yam 32 passes in use. In that way, the path of the cotton yam 32 along the feed system 110 is enclosed, and thus the cotton yam 32 and the Lycra yam 34 cannot collide, through any inadvertent interference or otherwise.

Figure 3 shows a device 40 for incorporation in a feed system of similar constmction to the feed system 110 of Figure 2 in place of the tube 36. In so far as certain features of the feed system of Figure 3 are identical with those of Figures 1 and 2, they are accorded the same reference numerals. Only those features of the device 40 of Figure 3 which are not present in the feeder system 10 of Figure 1 or the feeder system 110 of Figure 2 will now be described. A device 40 to enable two yams to be supplied to the feeder of a knitting machine comprises a housing 42, which is preferably an aluminium casting. The housing 42 is of elongated construction and includes a through bore 44 with apertures, 46 48 at either end. A further bore 50 in the housing 42 receives a ceramic tube 52.

A valve 54 is mounted on the housing 42 in communication with the aperture 48 of the bore 44. ^'•> The valve 54 is operable by means of a button 56 to allow compressed air into the bore 44. The button 56 is spring loaded, and is biased towards the closed position. The button 56 is manually operable to open the valve 54.

In normal operation, the hard yam enters the ceramic tube 52 at its free end, passes through the tube 52 and into the bore 44 leaving the bore 44 through the aperture 46 where it is fed to the aperture 28 of as feeder 14 of the type shown in Figures 1 and 2. The housing 42 prevents the hard yam 32 from contacting the resilient yam 34.

If the hard yam 32 breaks, the needle has to be rethreaded. Operation of the valve 54 by manual operation of the push button 56 directs compressed air into the bore 44. The yam in the tube 52 or bore 44 is drawn by the current of air through the feeder 14 and the needle is threaded automatically.

It is also possible to provide a barrier to prevent the yam 34 from being fed to an adjacent feeder. Such a barrier is suitably in the form of a ring, preferably made of metal to form a blade, and is located adjacent to the aperture 30.

The invention allows the production of knitted fabric incorporating two yams plated together, with a reduced likelihood of faults arising through the incorrect supply of yam to the needles.

Claims

1 A device to enable two yams to be supplied separately to the feeder of a knitting machine, which feeder is of the type in which each of the yams is fed through an aperture to a needle, which device comprises an elongated housing defining an enclosed path extending between an exit aperture located at one end of the housing and adapted to be mounted in contact with an aperture of the feeder and a second aperture located at the end of the housing remote from the exit aperture, for receiving yam from a yam store.

2 A device according to claim 1 wherein the elongated housing is a casting.

3 A device according to claim 1 or claim 2, wherein the housing is provided with a further aperture for the supply of compressed air to the enclosed path.

4 A device substantially as herein described, with reference to Figures 2 and 3 of the accompanying drawings.

5 A feed system for feeding two yams to a knitting machine, wherein a device according to any of claims 1 to 4 is mounted on the feeder, on the side of the feeder remote from the needle.

6 A feed system according to claim 5 which further comprises a barrer to prevent the yam which is not being fed through the housing, from being fed to an adjacent feeder.

7 A method of feeding two yams separately to a knitting machine, wherein one of the yams is a hard yam and the other of the yams is a resilient yam, and the hard yam is supplied to the feeder through a device according to any of claims 1 to 4.

3 A method according to claim 6 wherein the device is a device according to claim 3 and compressed air is supplied selectively to the housing, in the event of the yam breaking, in order to rethread the needle.