WO1995019463A1

WO1995019463A1 - Knitting apparatus

Info

Publication number: WO1995019463A1
Application number: PCT/GB1995/000060
Authority: WO
Inventors: Norman Alan Brunton; Robert John Tipler
Original assignee: Monarch Knitting Machinery (Uk) Limited
Priority date: 1994-01-15
Filing date: 1995-01-12
Publication date: 1995-07-20

Abstract

A lint removal system is disclosed for removing lint from a circular knitting machine (1) and at least one associated creel (2) supplying yarn to the knitting machine. The system comprises an extraction hood (6) disposed above the knitting machine and connected via a duct (4) to a suction unit (3), and a housing enclosing the creel and having an air outlet connected via a duct (5) to the suction unit for removal of lint from the creel housing. The creel has its supports for yarn packages located in the housing so as to support the packages in the air stream sucked through the housing between an air inlet of the housing and the air outlet.

Description

Knitting Apparatus

The present invention relates to industrial knitting apparatus and, more particularly, to lint removal systems for knitting apparatus for the removal and collection of lint dust and other waste material. Hereinafter, such material will be generally referred to simply as lint.

In industrial knitting systems, in particular those using circular knitting machines, the generation of lint, that is, fragments of yarn, is unavoidable. Lint is formed, for example, wherever the yarn travels over a machine part. Some of the lint accumulates on the equipment and some is released into the environment. The accumulation of lint on the knitting machine and associated equipment means that these must be cleaned periodically, during which time the machine is inoperative. Airborne lint can cause colour contamination of yarns and, also, presents a health and fire hazard. Previous attempts to overcome the problems caused by lint generation have generally relied on fans or the like to blow lint away from the machine knitting head, yarn feeding equipment and creels. While this may inhibit the accumulation of lint on the knitting machine, it does not solve, and may even exacerbate, the problems caused by airborne lint. The use of suction or extraction hoods for removing lint from knitting machines has also been proposed, for example, in GB-A-1 557 215 and 2 122 653. Similar problems of lint generation are encountered in yarn creel systems. Lint is formed when the yarn is unwound from the yarn packages, such as pay-off bobbins or spools, and wherever it travels over or through a yarn guide. It also collects on the stationary reserve yarn packages. Enclosed creels have been proposed which contain fans generating airflows which circulate within and/or flow out of, the enclosures through filters for collecting the lint. Examples of such creel cleaning systems are described in US-A-4 551 927 and EP-A-0 509 483. They suffer from the disadvantage, however, that the filters must be cleaned from time to time and, also, that the enclosures must be fitted with doors to permit access.

It is an object of the present invention to provide a lint removal system for use with knitting apparatus which overcomes or substantially mitigates the above-mentioned problems. From one aspect, the invention consists in a knitting apparatus comprising a circular knitting machine, at least one creel having supports for packages of yarn to be fed to the knitting machine, and a lint removal system, characterised in that the lint removal system comprises an extraction hood disposed above the knitting machine and via which lint is removable from the machine, a duct for connecting the hood to a suction unit, and a housing enclosing the or each creel and having air inlet means and air outlet means adapted to be connected to the suction unit for removal of lint from the creel housing, the supports for^"the yarn packages being disposed in the housing so as to support the yarn packages in the air stream between the inlet and outlet means. The lint removal system of the invention is advantageous in that both accumulated and airborne lint can be collected. This reduces the problems associated with lint generation, such as fabric defects, and the health and fire risks associated with airborne lint and dust (particularly cotton dust) . The efficient removal of lint may enable the knitting machine to be operated at higher speed and, in addition, the interval between machine cleaning operations may be significantly increased, resulting in increased productivity.

Another particular advantage of the lint removal system is that the same suction unit may be used to remove lint from both the knitting machine and the associated creel(s). The extraction hood may have any form adapted to facilitate airflow over the machine knitting head and into its suction duct. It may, for example, include a downwardly depending circular air deflector, the diameter of . which is preferably somewhat larger than the diameter of the machine knitting head. Preferably, however, the hood is generally conical.

The suction unit may be of generally conventional form including, for example, an impeller, and a lint collection receptacle, and be generally constructed as a free standing unit positioned to the side of the knitting machine. Alternative, it may be a larger unit located away from the knitting machines for multi-machine installations. The lint collection receptacle may be a removable bag. Air exhausted from the suction unit is preferably filtered, the filter conveniently being one which satisfies relevant health and safety requirements so as to permit the expelled air to pass directly back to the working environment. The duct for connecting the extraction hood to the suction unit may, for example, be a metal or plastics pipe, and may have a relatively large diameter, typically of the order of 15 to 30cm.

A plurality of creels may, and generally are, used in association with each knitting machine. Air may be drawn simultaneously from the knitting machine and from each associated creel. However, this increases the overall air flow necessary for efficient operation. It may, therefore, be an alternative for air to be drawn from the various pieces of equipment sequentially.

The suction unit may also be connected, via a flexible tube, to a suction nozzle which may be used to remove any lint which collects on, or in the vicinity of, the system. The flexible tube may be permanently connected to the suction unit. Alternatively, the flexible tube may be connected to the suction unit only as and when required, e.g. to a suitable socket in the suction duct of the extraction hood. In any event, the suction nozzle may be used to collect accumulated lint etc. whilst the knitting machine remains in operation.

Although the suction unit will generally be a stand-alone unit which is dedicated to the knitting assembly, in principle the suction unit could also be used for another purpose, e.g. as part of an air- conditioning system.

From another aspect, the invention consists in knitting apparatus comprising a circular knitting machine and a lint removal system characterised in that the lint removal system comprises an extraction hood disposed above the machine and via which lint is removable from the machine, a duct for connecting the hood to the suction unit, and one or more fans arranged to blow air inwardly of the machine for dislodging lint from the machine and removal via the extraction hood.

In one embodiment, the fan(s) are mounted for orbital motion about the knitting machine and are arranged to blow air inwardly towards the machine knitting head, in a direction generally towards the centre of the machine. Conveniently, the or each fan is mounted at the end of a radial support arm which rotates about a vertical axis substantially coaxial with the machine knitting head.

An important distinction between the lint removal system of this invention and conventional systems, where lint is generally blown outwards into the surrounding environment, is that with the present invention lint is blown in the opposite direction towards the centre of the machine and into the airflow created by the suction unit. This is an added benefit when manual cleaning does eventually become necessary.

According to a further aspect of the invention, there is provided creel apparatus for a knitting or other textile machine, comprising a housing having air inlet and outlet means, supports for yarn packages mounted in the housing so as to support the yarn packages in the air stream between the inlet and outlet means, and a duct for connecting the air outlet means to a suction unit for removing lint from the creel housing. With this arrangement, air is drawn through the air inlet, past the yarn packages, and through the air outlet to the suction unit, and lint from the vicinity of the yarn packages is entrained in the airflow for collection in the receptacle in the suction unit. With the invention, the duct connecting the air outlet to the suction unit may, similarly to the duct connected to the extraction hood of the knitting machine, have a relatively large cross section to alleviate clogging.

The air inlet means may simply be an open side of the housing, opposite to the air outlet. Alternatively, the housing may be fully enclosed, the air inlet being an opening or openings in the wall opposite to the air outlet. Particularly if fully enclosed, the housing may be provided with a door, e.g. a hinged or sliding door, for access to the yarn packages. Preferably, the air inlet means incorporates a filter screen in the form of a gauze or mesh panel which may occupy substantially all of one side of the creel housing so as to be at least coextensive with the yarn packages. The mesh size is preferably of the order of l-2mm and the mesh is most conveniently made of plastics material.

In one embodiment, in which the yarn package supports are arranged in a vertical column or stack, the air outlet means is a series of apertures in the wall of the creel opposite to the air inlet means. Alternatively, and preferably, the air outlet means may simply be a single slot extending along substantially the full height of that wall.

In any event, the air inlet and outlet means are preferably positioned such that the airflow between them passes over the yarn packages.

The slot(s) functioning as the air outlet may typically have a width of between 5mm and 40mm. It has been found that a slot width of 10mm is particularly effective. In general, the narrower the slot, the higher the velocity of air flowing through it. The air velocity should be sufficiently high to be effective in entraining the lint, but not so high as to deflect the yarns.

It is preferred that the side walls of the creel converge towards the air outlet means so as to provide a smooth airflow through the creel.

The yarn may travel from the creel to the knitting machine through yarn guide tubes, as is known. The intake ends of these guide tubes are preferably positioned close to the air outlet means, so that the yarn travels in the same direction as the airflow from the air inlet to the air outlet.

The invention will now be described in more detail and by way of illustration only with reference to the accompanying drawings, in which : -

Figure 1 is a schematic view of knitting apparatus embodying the invention,

Figure 2 is a detailed view, partially in section, of the circular knitting machine forming part of the apparatus of Figure 1,

Figure 3 is a perspective view of the yarn creel forming part of the apparatus of Figure 1 and also illustrates in broken lines how several such creels may be arranged in a bank for supplying the knitting machine, and

Figure 4 is a schematic view illustrating the construction of the suction unit of Figure 1.

Referring to Figure 1, the knitting apparatus includes a circular knitting machine 1 which is fed with yarn from a number of creels 2 (for simplicity only one creel is shown in Figure 1) . The apparatus also includes a suction unit 3 which is connected to the knitting machine 1 by a first suction duct 4 and to the creel 2 by a second suction duct 5. The first duct 4 is connected to an extraction hood 6 in the form of a downwardly depending conical funnel positioned above the knitting head 7 of the knitting machine 1 and substantially coaxially with the machine. A flexible pipe 8 is connected to the first duct 4 and is provided at its free end with a nozzle

9.

As best seen in Figure 4, the suction unit

3 is of generally conventional design and comprises a casing 10 having an impeller and electric motor assembly 11 disposed in an upper chamber 12 of the casing, , the outlet of the impeller being connected to an exhaust outlet 13 for clean air in the top of the casing. The inlet of the impeller is connected to a filter assembly 14 located below the assembly 11 in an intermediate chamber 15 of the casing. Air drawn through the suction ducts 4,5 by operation of the impeller is supplied to the filter assembly 14 via an air inlet 16 and a lint collecting funnel 17 disposed in the lower chamber 18 of the casing 10. Lint removed by the filter assembly 14 and collected in the funnel 17 is discharged via a discharge opening in the neck 19 of the funnel into a lint collection bag 20, such as a disposable plastic bag, releasably attached to the funnel neck by means of a suitable strapping device 21. The suction unit is also provided with a control panel (not shown) and access doors to the three chambers 12,15,18, including a door 22 (Figure 1) which can be opened to provide access to the lower chamber 18 for removal of a full collection bag 20.

Figure 2 illustrates in more detail the arrangement of the extraction hood 6 above the knitting head 7 of the knitting machine 1. The hood is supported generally coaxially of the machine 1 in an annular plate 23 secured to a ring frame member 24 supported in a position spaced above the head 7 by three frame posts 25 projecting upwardly from the main frame of the knitting machine 1 at equally spaced positions thereabout. Attached to the upper side of the annular plate 23 at equally spaced positions are six radial arms 26 having downwardly depending brackets 27 at their outer ends supporting mounting rings 28 for yarn feed wheels 29. As is conventional, the yarn feed wheels are driven in a controlled manner from drive wheels 30 mounted on a pedestal projecting upwardly from the main frame of the knitting machine and coupled to the yarn feed wheels by drive tapes (not shown) engaging the drive wheels 30 and driven wheels 32 fixed to the spindles of the yarn guide wheels.

Depending from the ring member 24 is a yarn spreader support assembly 33 which supports the upper end of the spindle 34 of a rotary fabric spreader. The assembly 33 comprises three equally spaced posts 36 projecting downwardly from the plate 23 and into the interior of the extraction hood. Carried on the bottom ends of these posts is a mounting plate 37 for the bearing for the upper end of the spindle 34, of the yarn spreader. Supported on an annular plate 38 disposed about the hood 6 and secured to the inner ends of the radial arms 26 is a frame 39 for supporting an orbital fan assembly 40 which is directed to blow cleaning air downwardly and inwardly towards the centre of the knitting machine 1 and onto the knitting machine head 7. The frame 39 comprises three upright posts 41 disposed at equally spaced positions about the annular plate 38 and supporting a mounting plate 42 at their upper ends in which is carried a vertical sleeve 43 mounting a vertically adjustable shaft 44. The latter is mounted substantially coaxially of the machine 1 and is slidable within the sleeve 43. Journalled on the upper end of the shaft 44 is an electric drive motor 45 which is rotatable about the shaft in order to provide for the orbital movement of the fan assembly 40. The fan assembly comprises a fan 46 and electric drive motor 47 and is articulated to the outer end of a radial support arm 48 by an adjustable joint 49. The support arm 48, itself, is mounted at its inner end in a clamp on the casing of the drive motor 45. It is clamped in a radially adjusted position by the clamping wheel 50. The adjustable joint 49 is lockable in a selected position and enables the angle of the downwardly directed airflow produced by the fan 46. The vertical height of the fan can be altered by adjusting the shaft 44 relative to its mounting sleeve 43.

Referring to Figure 3, the creel 2 comprises an elongated upright housing 51 having a roof 52 and a floor 53 interconnected by upright metal frame members 54. The sides 55 of the housing are glazed between the frame members 54 with clear plastic sheeting, whilst the front side includes a door 57 hinged to a frame member 54 at one corner of the housing. The door is constructed with filter screen panels 58 formed from plastics mesh and provides an air inlet to the housing 51. Towards the back of the housing, the sides 55 converge to a back wall 56 which is formed with an air outlet slot 59 extending for substantially the full height of the housing. The slot 59 is preferably about 10mm wide and opens into a vertical manifold 60 of square cross section which, in turn, communicates at its upper end with the second suction duct 5. Pin supports 61 for pay-off bobbins or yarn packages 62 are arranged within the creel housing in two side-bγ-side columns at the front side of the housing. They project inwardly from convenient frame members 54 at the front side so as to support the yarn packages 62 within the housing in the airflow between the air inlet door 57 and the air outlet slot 59 of the housing. Only half of the yarn packages are in use at any one time, the remainder being reserve packages. Yarn guide tubes 63 extend from the knitting machine 1 to the creel and enter the creel housing through its roof 52 and adjacent the back of the housing. The tubes 63 terminate at positions adjacent the air outlet slot 59 so that the intake ends 64 of each tube is opposite to the pin support 61 for an associated yarn package 62. Yarn is fed from the associated yarn package into the intake end of the yarn guide tube and then to the knitting machine 1.

As illustrated in broken lines in Figure 3, two or more creels 2,2a,2b of the above construction may be arranged side-by-side and/or back-to-back to form a bank of creels. Two creels 2,2b arranged back- to-back may have their air outlet slots 59 connected by a common manifold 60 to the suction duct 5 whilst creels 2,2a located side-by-side are connected by individual manifolds 60,60a to the duct. Alternatively, creels 2,2b arranged back-to-back may have individual manifold connections to the suction duct 5 and, in other embodiments, each creel 2,2a,2b may have a separate suction duct connector to the suction unit.

In the operation of the lint cleaning system, air is drawn by the suction unit 3 along the first and second ducts 4,5 either simultaneously or sequentially. At the knitting machine, as the fan 46 orbits the machine under the control of the motor 45, it produces a flow of cleaning air downwardly and inwardly over the yarn feed wheels and associated equipment and towards the centre of the machine. This air flow or stream dislodges and entrains lint, whereafter the lint is removed with the air drawn through the extraction hood 6 and suction duct 4, as illustrated by the arrows in Figure 2. At the creel 2, air is drawn through the creel housing 51, from the filter screen panels 58 in the door 57, over the yarn packages 62 and the intake ends 64 of the yarn guide tubes and extracted through the outlet slot 59 into the suction duct 5. Lint entrained in the airflows in the suction ducts 4,5 is removed from these airflows by the filter assembly 14 in the suction unit and falls into the collection bag 20. As and when required, this bag is removed from the suction unit and emptied or replaced.

During operation of the system, lint which accumulates on exterior surfaces of the apparatus, for example on the exterior of the screen panels 58 of the creel door, may be removed and collected using the flexible pipe and nozzle 8,9. The pipe 8 may be permanently connected to the first suction duct 4. However, it is preferably attached to a suitable socket in the duct as and when required for use.

Whilst particular embodiments have been described, it will be understood that modifications may be made without departing from the scope of the invention as defined by the appended claims. For example, an additional orbital fan assembly 40 may be mounted on a radial support arm at a diametrically opposite position to the fan assembly 40 illustrated in Figure 2 so as to provide another cleaning air flow downwardly and inwardly towards the centre of the knitting machine.

Claims

1. Knitting apparatus comprising a circular knitting machine (1) , at least one creel (2) having supports (61) for packages (62) of yarn to be fed to the knitting machine, and a lint removal system, characterised in that the lint removal system comprises an extraction hood (6) disposed above the knitting machine (1) and via which lint is removable from the machine , a duct (4) for connecting the hood to a suction unit (3), and a housing (5) enclosing the or each creel and having air inlet means (57) and air outlet means (59) adapted to be connected to the suction unit for removal of lint from the creel housing, the supports (61) for the yarn packages (62) being disposed in the housing (51) so as to support the yarn packages in the air stream between the inlet and outlet means.

2. Apparatus according to claim 1, wherein the lint removal system includes one or more fans (46) arranged to blow air inwardly of the knitting machine (1) for dislodging lint from the machine and removal via the extraction hood (6).

3. Knitting apparatus comprising a circular knitting machine (1) and a lint removal system characterised in that the lint removal system comprises an extraction hood (6) disposed above the machine (1) and via which lint is removable from the machine, a duct (4) for connecting the hood (6) to the suction unit (3), and one or more fans (46) arranged to blow air inwardly of the machine (1) for dislodging lint from the machine and removal via the extraction hood (6) .

4. Apparatus according to claim 2 or 3, wherein the fan(s) (46) are located above the knitting machine (1) and the intake to the extraction hood (6) so as to blow air downwardly and inwardly onto the knitting machine.

5. Apparatus according to claim 2, 3 or 4, wherein the fan(s) are mounted for rotation about the knitting machine.

6. Apparatus according to claim 5, wherein the or each fan (46) is mounted on an arm (48) projecting substantially radially of the machine (1) and the arm is mounted for rotation about an axis substantially coaxial with the knitting machine.

7. Creel apparatus for a knitting or other textile machine comprising a housing (51) having air inlet and outlet means (57,59), supports (61) for yarn packages (62) mounted in the housing so as to support the yarn packages in the air stream between the inlet and outlet means, and a duct (5) for connecting the air outlet means (59) to a suction unit (3) for removing lint from the creel housing (51).

8. Apparatus as claimed in any preceding claim, wherein the or each creel housing (51) is an elongated housing and the yarn package supports (61) are arranged in one or more columns generally parallel to the longitudinal axis of the housing, and wherein the air inlet and outlet means (57,59) are positioned so that the cleaning air stream produced in the housing by the suction unit is in a direction generally orthogonal to the columns of package supports (61).

9. Apparatus according to any preceding claim, wherein the or each creel housing (51) has yarn guide tubes (63) for feeding yarn from the creel (2) to the machine (1), the intake end (64) of each yarn guide tube being arranged relative to its associated yarn package support (61) so that the yarn is fed from a yarn package to the associated yarn guide tube (63) in the direction of the air stream between the air inlet and outlet means.

10. Apparatus according to claim 9, wherein the yarn guide supports (61) are mounted adjacent the air inlet means (57) and the intake ends (64) of the yarn guide tubes are disposed adjacent the air outlet means (59)

11. Apparatus according to any preceding claim, wherein the air inlet means (57) comprises an air inlet opening or openings in a side of the housing (51) adjacent the yarn supports (1) and substantially coextensive therewith and the air outlet means comprises an elongated slot (59) in the opposite side of the housing.

12. Apparatus according to claim 11, wherein the supports (61) for the yarn packages are arranged in side-by-side columns adjacent to and coextensive with the air inlet means, and the air inlet means comprises a door providing access to the creel housing (51).

13. Apparatus according to any preceding claim, wherein the air inlet means (57) incorporates at least one filter screen (58).

14. Apparatus according to any preceding claim, wherein the extraction hood (6) includes a downwardly directed conical air deflector, the intake diameter of which is larger than the diameter of the knitting machine head (7) .

15. Apparatus according to any preceding claim, including a suction unit (3) adapted to draw air sequentially from the extraction hood and the or each creel housing (21).

16. Apparatus according to any preceding claim, including a suction unit (3) having a lint collection receptacle (20) for collecting lint entrained in the suction air stream drawn into the suction unit.

17. Apparatus according to claim 16, wherein the suction unit (3) comprises a suction fan assembly (11) connected to the suction ducts (4,5) via filter means (14) and wherein the lint collection receptacle (20) is arranged adjacent the intake side of the filter means (14) to collect lint entrained in the suction air stream.