US3791177A

US3791177A - Circular knitting machines

Info

Publication number: US3791177A
Application number: US00217332A
Authority: US
Inventors: B Swanwick; C Roper; D Gell
Original assignee: STIBBE MACHINERY Ltd
Current assignee: STIBBE MACHINERY Ltd
Priority date: 1971-01-21
Filing date: 1972-01-12
Publication date: 1974-02-12
Anticipated expiration: 1991-02-12
Also published as: IT949663B; DE2202951A1; CH544174A; FR2122989A5; GB1371049A

Abstract

Method and apparatus for stacking knitted fabric issuing from a circular knitting machine in layers in a container by imparting reciprocal motion to the fabric so that it is folded in concertina fashion. The means for layering the fabric are in the form of a pair of rods or rollers driven by reversible or nonreversible drive means, said rods or rollers operating in a stationary horizontal plane, or being raised in increments with the stacked fabric.

Description

United Sttes Patet [191 Swanwick et al.

[ Feb. 12, 11974 CIRCULAR KNITTING MAC 1: 1| 1 Inventors: Barry Frederick Swanwick,

Melton Mowbray; Coiin Vincent Roper, Braunstone; Dennis Gell, Leicester, all of England Stibbe Machinery Limited, Leicester, England Filed: Jan. 12, 1972 Appl. No.: 217,332

Assignee:

Foreign Application Priority Data Jan. 21, 1971 Bulgaria 2,850/71 US. Cl. 66/147 Int. Cl. D04b 35/00 Field of Search..... 66/147, 149, 153, 151, 152,

References Cited UNITED STATES PATENTS 7/1970 Tannert 66/142 X Miller 270/79 X 2,653,812 9/1953 Cohneta 270/79 2,218,062 10/1940 Yates 270/79 3,499,643 10/1967 Biggar 270/79 3,423,083 l/1969 Sherrill 270/79 X 2,016,539 10/1935 Brenn 270/79 2,723,546 11/1955 Buckreus.... 66/147 2,497,786 2/1950 Miller 66/152 3,037,768 6/1962 Anderson et a]. 270/79 X FOREIGN PATENTS OR APPLICATIONS 53,564 8/1910 Switzerland 270/39 Primary ExaminerRonald Feldbaum [5 7] ABSTRACT Method and apparatus for stacking knitted fabric issuing from a circular knitting machine in layers in a container by imparting reciprocal motion to the fabric so that it is folded in Concertina fashion. The means for layering the fabric are in the form of a pair of rods or rollers driven by reversible or non-reversible drive means, said rods or rollers operating in a stationary horizontal plane, or being raised in increments with the stacked fabric.

22 Claims, 12 Drawing Figures PATENTEDFEB 12 I974 sum 1 or 7 CIRCULAR KNITTING MACHINES This invention relates to circular knitting machines, and more particularly to a method of, and means for, automatically stacking knitted fabric in a container in continuation of the knitting thereof on large diameter circular knitting machines. By the term large diameter in this instance is meant machines having a knitting diameter of about inches and over.

At present the work take-off machanisms of large diameter circular knitting machines comprise a pair of co-acting work take-off which tension the fabric away from the needles, which are followed by a winding-up roller on which the fabric is wound as it issues from the take-off rollers.

Such mechanisms are becoming costly, and difficult to handle, as modern machines are producing fabric at ever increasing rates which gives rise to more frequent stoppages to unload the winding-up rollers. In an endeavour to alleviate this problem, the winding-up rollers are being allowed to wind-up more fabric thus making them very heavy and bulky to handle. A- further disadvantage of rolling up the fabric is that, when knitting with synthetic yarns, the act of rolling the fabric causes permanent creases therein.

It has been proposed, in order to overcome this problem, that instead of winding-up the fabric it be allowed to collect in a bin which, when full, can be wheeled out of the way and replaced by an empty one. This, of course, means that less time is lost during each stoppage since the fabric is more easily handled. Also, by raising the knitting head further from the floor, more fabric can be collected in the bin which, in the case of rotating cylinder knitting machines, is supported on a rotating platform and rotates with the needle cylinder and take-off rollers.

The problem arising from the latter method is that, although the fabric may fall into the bin and form layers, each layer does not necessarily cover the whole width of the bin and a pile of layers in the centre of the bin tends to be formed. This lack of complete use of the area of the bin is obviously wasteful and defeats the object of collecting more fabric per machine run. Furthermore, in an attempt to avoid the latter disadvantage, it is necessary for the operator to stop the machine frequently in order to re-arrange the random layers in the bin.

It is among the objects of the present invention to overcome or substantially reduce the aforementioned disadvantages.

According to the present invention, there is provided a method of stacking knitted fabric, in layers, in a container in continuation of the knitting thereof, which comprises continuously feeding the knitted fabric into the container and simultaneously causing the fabric to be folded, in concertina fashion, and in a uniform manner, over the width or the length of the container.

According to the invention furthermore, there is provided apparatus for stacking knitted fabric, in layers, in a container in continuation of the knitting thereof, which comprises means for guiding the fabric issuing from the knitting machine in a to-and-fro motion whereby the fabric will be folded, in concertina fashion, and in a uniform manner, over the width or the length of the container.

Themeans for guiding the fabric may comprise mechanical guide members which are reciprocated over the width or length of the container. Such reciprocation may be effected by a reversible drive motor, or alternatively, by a non-reversible drive motor through an endless chain drive.

Alternatively, the means for guiding the fabric may comprise pneumatic means in the form of a jet or jets of air under pressure arranged adjacent two opposite sides of the container, means being provided to control the operation of the air jets so that the fabric is guided by the air from opposite sides alternately.

In the case of a rotating cylinder machine the whole mechanism is of course mounted on a platform to rotate with the needle cylinder within the base of the machine.

The invention, as applied to a rotating cylinder type machine, is illustrated by way of example in the accompanying drawings in which,

FIG. 1 is an end elevation, partly in section, showing one embodiment of the fabric layering apparatus according to the invention, and also showing certain parts of the knitting machine with which the apparatus is used,

FIG. 2 is a side elevation corresponding to FIG. 1 but showing only the essential parts of the apparatus,

FIG. 3 is a part plan view corresponding to FIG. 2,

FIG. 4 is a detail, on an enlarged scale, of part of FIG.

FIG. 5 is a plan view of an alternative embodiment of the invention,

FIG. 6 is a side elevation corresponding to FIG. 5, certain parts of the apparatus being omitted,

FIG. 7 is a side elevation showing a modification of the embodiment of FIGS. 5 and 6,

FIGS. 8, 9 and 10 are details showing the mode of operation of the embodiment of FIG. 7,

FIG. 11 is a side elevation of a further modification of the embodiment of FIGS. 5 and 6, and

FIG. 12 is a schematic elevation of a further alternative embodiment of the invention.

Referring to FIGS. 1 to 4 of the drawings, there is shown the lower part of a circular knitting machine 1 having supporting legs 2 to which a stationary base plate 3 is fixed. Mounted on the base plate 3, with an annular bearing 4 interposed is a rotary table 5 which supports the fabric tensioning and collecting equipment generally indicated by a pair of tensioning rollers 6 and supporting posts 7.

The tensioning rollers 6 are driven in well known manner in synchronism with the fabric output. One such arrangement of fabric tensioning means is shown in our prior British Patent Specification No. 1,1 18,547. However, other arrangements may be used such as a brush tensioning mechanism of the kind described in British Patent Specification No. 729920 of G. Lebocey or a spiked roller mechanism of the kind described in British Patent Specification No. 671477 of Mellor Bromley Limited. In the latter arrangements, the tensioning mechanisms are arranged in circular formation within the tubular fabric and, in order to adapt such arrangements for use with the layering apparatus of the present invention, it is only necessary to arrange two guide bars or rollers below the tensioning means to close the tubular fabric into a substantially flat form before it is fed to the layering apparatus.

The rotary table 5 also supports the layering apparatus of the invention which comprises generally a pair of fabric layering rollers 8 and 9', a pair of spaced support frames 10, and a fabric-receiving container 11 which is removably supported on support blocks 12 between the frames 10.

The fabric layering rollers 8 and 9 are supported and driven at each end thereof in exactly the same manner and therefore the following description will be with respect to one end only thereof. Thus, the rollers 8 and 9 are mounted respectively on shaft 13 and 14 which are each provided with a freely rotatably roller 15. The roller 15 are positioned to run over a guide surface 16 provided on the frame 10 to provide heightwise location for the rollers 8 and 9. Also mounted on the shafts 13 and 14 are gear wheels 17, these gear wheels being fixed to the shafts and being adapted to engage a toothed rack 18 provided on the frame 10. In this respect, for the reason hereinafter described, the rack 18 does not extend over the full length of the container 1 1.

The gear wheels 17 each incorporate a one-way gear to known construction which includes a pawl and ratchet mechanism so that the gear wheel is positively driven in one direction only. Thus, movement of the rollers 8 and 9, by means hereinafter described, in one direction is effective to cause one gear wheel 17 to positively rotate its co-acting roller, whereas movement of the rollers 8 and 9 in the opposite direction is effective to cause the other gear wheel 17 to positively rotate its co-acting roller. The arrangement of the gear wheels 17 and their one-way gears is such that rotation of the roller 8 or the roller 9 is in a direction that, in use, causes the fabric to be fed in a downward direction, it being understood that the roller which is not being positively driven is free-wheeling and is rotated by the pressure applied thereto by the positively driven roller via the fabric.

The means for effecting movement, that is to say reciprocal movement, of the rollers 8 and 9, and the means for urging the rollers into engagement with each other, will now be described with particular reference to FIGS. 2 and 4 of the drawings. Thus, the end of the shafts l3 and 14 extend through slotted holes 19 in a coupling link 20 and also, respectively, through a hole in one end of a pair of connecting links 21. The other ends of the connecting links 21 are hingedly connected together by a hinge pin 22 and, at a mid-position, the links 21 are coupled together by a tension spring 23. Thus, it will be seen that the shafts 13 and 14, and thus also the rollers 8 and 9, are urged towards each other by the spring 23.

For the purpose of causing reciprocal movement of the rollers 8 and 9, a driving link 24 is connected between an endless drive chain 25 and the centre of the coupling link 20, the link 24 being formed with a slot 26 so that a pin 27, which secures it to the link 20, is slidable therein. The chain 25 is continuously driven in one direction by means hereinafter described and is mounted for this purpose on end sprockets 28 and 29. It will be noted that, in the drawings, the rollers 8 and 9 are being moved from right and left and therefore positive drive is being applied to the roller 8 by its coacting gear wheel 17.

On reaching the left hand end of the stroke of the layering rollers 8 and 9, it will be seen that the latter stop whilst the drive link 24 moves round the sprocket 28 and takes up the position shown in chain dot lines in FIG. 4. When this position is reached, the rollers 8 and 9 will be moved in the opposite direction, i.e. from left to right.

During the aforementioned pause in the movement of the rollers 8 and 9, it will be appreciated that since rotation of the rollers is dependent upon movement thereof relative to the toothed rack 18, the rollers 8 and 9 will also stop rotating. However, to ensure proper layering of the fabric, it is preferably that the rollers 8 and 9 should continue to rotate during said pause in order that continued feeding of the fabric should take place. For this purpose, the rack 18 stops short of the end of the frame 10 so that the gear wheels 17 move out of engagement with the rack. In addition, a sprocket wheels 30 is mounted on the shaft 13 to enter into engagement with the drive chain 25. The sprocket wheel 30 is of the same type as that of the gear wheels 17, i.e. it incorporates a one-way gear mechanism consisting of ratchet 31 and a pawl 32 so that it drives in one direction only.

Thus, it will be seen that, whilst the rollers 8 and 9 are being moved, there is no relative movement between the gear wheel 17 mounted on the shaft 13 and the sprocket wheel 30 because they are both being turned in the same direction. However, when the roller 8 and 9 come to the end of a stroke and the gear wheels 17 become disengaged from the rack 18, the rollers remain stationary and continue movement of the chain 25 causes rotation of the sprocket wheel 30 in an anticlockwise direction. This causes interengagement between the ratchet 31 and the pawl 32 and effects positive rotation of the roller 8 and thus also rotation of the roller 9. On the return stroke of the rollers 8 and 9, rotation of the latter will again be effected by the rack 18 and the gear wheel 17 of the roller 8 will be freewheeling in synchronism with the sprocket wheel 30.

Since the chain 25 always travels in the same direction it is only necessary to provide a sprocket wheel 30 on the shaft 13 and this of course causes rotation of both layering rollers 8 and 9.

The chain sprockets 28 and 29 are mounted on stub axles 33 and 34 fixed to brackets 35 provided on the frame 10. For the purpose of imparting drive to the chain 25, a further sprocket wheel 36 is mounted on the stub axle 33 and is secured to the sprocket wheel 28 so that they rotate in unison. Arranged on the stationary base plate 3 is a magnetic particle coupling 37 of known construction. The output shaft of the coupling 37 has fixed thereto a bevel gear 38 whilst the input shaft thereof is fixed to the stationary base plate 3. The bevel gear 38 is in mesh with a bevel gear 39 fixed to a lay shaft 40. The shaft 40 has fixed thereto a chain sprocket 41 and a drive chain 42 extends between the sprockets 36 and 41 to impart drive to the chain 25. Thus, the coupling serves to apply a preset torque to the output shaft thereof and thus also to the bevel gear 38. In practice, it will be seen that the lay shaft 40 is turning with the layering apparatus whilst the output shaft of the coupling 37, which is fixed to the base plate 3, remains stationary. This condition generates rotation of the shaft 40 due to the fact that the bevel gear 39 moves round the bevel gear 38 and this will drive the chains 42 and 25 at a speed corresponding to the output of the knitting machine. If, however, the output shaft of the coupling 37 was freely rotatable relative to the base plate 3, it would merely rotate with the machine driven by the bevel gears 38 and 39 and no rotation of the shaft 40 would take place. Therefore, it will be seen that rotation of the lay shaft 40 can be governed by the amount of braking power which is applied thereto. This braking power is provided by the magnetic particle coupling 37 which is adapted to apply variable torque dependent upon the electronic power applied to its exciting coil. This action is governed by a potentiometer 43 which can be preset to provide a given output. Thus, the speed of transverse, and therefore the speed of rotation, of the layering rollers 8 and 9 is governed by the potentiometer 43.

Although only one potentiometer 43 has been described, it is possible to provide a plurality of potentiometers linked in parallel and all set at different levels, and switched into operation at pre-determined intervals, so as to provide different speeds of traverse, and therefore fabric consumption, of the rollers 8 and 9.

In operation, the fabric-receiving container 11 is positioned as shown in FIGS. 1 to 3 of the drawings and sufficient fabric F is knitted to be fed between the tensioning rollers 6 and the layering rollers 8 and 9 to reach the bottom of the container 11 where it may be fixed as by spring clips.

Knitting is then continued and the layering rollers 8 and 9 are reciprocated over the container 1 1 so that the knitted fabric will automatic-ally layer itself over the full length of the container 11. The rate of feed of the fabric through the rollers 8 and 9 is nominally set by the gear and chain drive ratios and the speed of traverse, and the feed can then be further adjusted by the potentiometer 43 which controls the magnetic particle coupling 37.

As previously stated, at the end of each stroke, lengthwise movement of the rollers 8 and 9 ceases whilst the drive link 24 changes its position from the upper run of the drive chain 25 to the lower run thereof, or vice versa. During this pause, the rollers 8 and 9 are rotated by the sprocket wheel so that fabric continues to be fed into the container 11. The reason for this is that it stops the tendancy of the fabric to be pulled away from the wall of the container 11 when the direction of movement of the rollers 8 and 9 is reversed, thereby enabling the container to be completely filled with the fabric which is layered in a neat and uniform manner.

When the container 11 is filled with fabric, the machine is stopped, the container is replaced, and the process is repeated with the minimum of delay.

The apparatus hereinbefore described may be modified for handling certain fabrics by providing means for positively holding each fold of the fabric in a position adjacent the end walls of the container 1 1. Such means comprise a pair of dropper arms 44 which are pivotally mounted in extensions 45 of the brackets to hang freely, under their own weight, within the container 11. The free ends of the arms 44 are preferably provided with means, such as rubber or nylon pads, to increase their gripping capabilities.

In use, as the layering rollers 8 and 9 approach the end of a storke, the arm 44 at that end is raised so that it will not interfere with the positioning of the fabric. The fabric is then folded over in the manner hereinbefore described and, as the rollers 8 and 9 move in the opposite direction, the arm 44 drops down onto the fold and prevents it from being pulled away from the end wall of the container 11. For this purpose, a cam plate 46 is positioned on the shafts l3 and 14 and has two cam surfaces 47, 48 which engage and lift the arms 44 respectively at the end of each stroke. To enable full movement of the cam plate 46 to take place without reducing the depth of the container 11, the latter is formed with slots 49 in its ends walls.

Referring now to the embodiment of FIGS. 5 and 6 of the drawings, there is shown a part of the framework of a rotating cylinder circular knitting machine having three legs 50, 51 and 52 one of which, as is usual with these machines, houses or supports a drive motor (not shown) and a main control mechanism. The legs are stationary but work take-off rollers 53 and 54, and their

supports

55 and 56, which also house the take-off roller drive mechanisms, are rotated in unison with the needle cylinder. This is accomplished by means of a work take-off carriage which is gear driven from the motor housed within leg 52.

The foregoing structure is known art and it is also known to use fabric receiving means, such as a container 57, to receive the fabric issuing from the take-off rollers 53 and 54. However, in carrying out the present invention, the container 57 is open-sided and has only a base 58, a front 59 and a back 60.

The container 57 is removable and is slidably received within, and supported by, location brackets 61 provided on a rotary table 62 so that, in use, it is possible to slide receptacles on and off the table 62 when changing a full container for an empty one.

Rotatably supported on the table 62 adjacent the corners of the fabric container 57 are four vertically disposed square-section-thread screws 63 which are also rotatably located, at their upper ends, in brackets (not shown) mounted on a revolving frame member of the knitting machine positioned above the fabric take-off rollers 53 and 54.

Each screw 63 has mounted thereon, by means of a mating screw-threaded hole, a co-acting bracket 64. The brackets 64 adjacent the back 60 of the container 57 support a drive shaft 65 on which are mounted, adjacent each bracket 64, sprocket wheels 66. The remaining two brackets 64 each have mounted thereon freely rotatable sprocket wheels 67. Extending between the

sprocket wheels

66 and 67 on opposite sides of the container 57 are drive chains 68. Centrally located on the drive shaft 65 is a reversible motor 69 which is attached to a bracket 70. The bracket 70 is formed with a projection which fits into a mating slideway formed on an upright post 71 so that the motor is movable, in a vertical direction, relative to the post 71.

Fixedly mounted on the lower end of the screws 63 are sprocket wheels 72. Passing round all of these sprockets wheels is a chain 73 so that, when one sprocket wheel turns, and thereby turns it co-acting screw 63 to raise its co-acting bracket 65, all the other sprocket wheels turn and raise their co-acting brackets 64.

Fixedly mounted on one of the screws 63 below the sprocket 72 is a star wheel 74. The star wheel 74 is turned, during rotation of the apparatus to carry out a knitting operation, by entering into contact with a cam 75 positioned on a stationary part of the machine, every time it passes said cam. There could of course be a multiple of star wheels 74 and/or cams 75 to impart varying amounts of vertical movement of the fabric guiding mechanism hereinafter described. The cam 75 is spring-loaded into an operative position and pulled out of action by a cable or other means under the control of the main control mechanism of the machine.

For manually raising and lowering the fabric guiding mechanism a handle is removably mounted on the top of one of the screws 63.

Power is supplied to the reversible motor 69 from a slip ring 76 arranged on a stationary part of the machine through contacts 77, an extension 78 of which is arranged vertically in the post 71 so as always to be in contact with the leads of the motor 69.

Positioned between, and fixed to, the two chains 68 are bars 79 and 80 through which the fabric is guided.

The bars 79 and 80 are driven backwards and forwards, as the fabric is drawn through the take-off rollers 53 and 54, by the motor 69 which, as stated, is a reversible motor. A suitable control mechanism is provided to reverse the direction of rotation of the motor after a predetermined number of rotations of the needle cylinder of the knitting machine has taken place.

In operation, the fabric guiding mechanism consisting of the bars 79 and 80 is raised manually to its highest position, just below the work take-off rollers 53, 54. The container 57 is then placed in position on the location brackets 61 of the table 62.

The fabric indicated at F is then knitted until it is of sufficient length to extend through the work take-off rollers 53 and 54 and the guiding bars 79 and 80 down to a corner of the container 57. The machine is then stopped and the end of the fabric is clipped into this corner by any suitable means such as detachable spring clips 81. The fabric guiding mechanism is then lowered to a position just above the base 58 of the container 57.

Knitting is then recommenced and the motor 69 started in order to impart reciprocatory movement to the bars 79 and 80. As the layers of fabric are formed, so the fabric guiding mechanism is raised by the cam 75 and star wheel 74. The motor and cam are operated in synchronism with the knitting machine output under the control of the main control mechanism of the machine.

When the fabric container 57 is full, the machine is stopped, either manually by the operator, or by virtue of an earthing circuit micro-switch 82 which is actuated by one of the brackets 64 as the latter reaches a predetermined height.

The fabric F is then cut leaving sufficient length to clamp into another fabric container for the next stacking cycle. The filled container is then removed and replaced by an empty one.

The container 57 is supported clear of the platform 62 by the brackets 61 in order to enable a fork-lift type of handling means to be used to take off the full containers.

Alternative arrangements of this specific embodiment are of course possible, one of which serves to further lengthen the container 57 and also ensures more accurate control over the folds of the layered fabric. Such an arrangement is shown in FIGS. 7 to 10 of the drawings which show only details which differ from FIGS. 5 and 6. In this case the motor 69 is mounted in a similar manner to that already described and shown but is offset from the chain sprockets 66 adjacent the back wall 60 of the container and drives these through gears or pulleys 83 and 84 and belt 85. A shaft 86 on which the pulley or sprocket 83 is mounted is driven by the motor 69 which is supported in the same manner as that shown in FIGS. 5 and 6.

In this arrangement, it can be seen that the container 57 is extended so that its front 59 and back 60 extend beyond the sprockets 66.

It is intended with this arrangement that the layering of the fabric is started as hereinbefore described but the bars 79 and 80 in this case move to a position part way round sprocket 67 as shown in FIGS. 7 and 8. The drive motor 69 is then stopped and the fabric allowed to continue to fall to the position shown in FIG. 9. As this point, the motor 69 is started up in the opposite direction so that the two bars 79 and 80 travel back along the fabric as is shown in FIG. 10. The bars continue to travel in this manner until the position shown in FIG. 7 is reached at the other end of the container 57.

Thus, it will be appreciated that, in this arrangement, the fabric folds are retained at the extreme ends of the container and are not pulled back by the bars 79 and 80 on their return movement. In this respect, the bars 79 and 80 could be replaced by freely rotatable rollers.

In order to ensure neat laying of the fabric in he receptacle, it may be advantageous to allow the bars or rollers 79 and 80 to actually rub or roll along the top of the stack to keep it packed down. For this purpose a modification of the arrangement of FIGS. 5 and 6 is shown in FIG. 11 wherein a sensing device to sense the level of the fabric relative to the bars 79 and 80 may be provided. Such a device would relay command signals to the drive mechanisms of screws 63 or its equivalent to stop or drive.

For this purpose a light beam sensing device such as photoelectric cell 87 may be fitted on one of the brackets 64 to co-act with a light source (not shown) fitted on the bracket 64 on the other side of container 57 at a position directly opposite photo-electric cell 87. The circuit from the photo-electric cell to the screw drive mechanism would be such that, when the light beam is totally cut-off by the rising layers of fabric, the cam is operated to engage the star wheel 74 to raise the bars 79 and until the light beam is just above the level of the layered fabric.

In the alternative embodiment shown in FIG. 12, the guide mechanism is dispensed with and use is made of a container 89 having four sides.

In this arrangement, nozzles 90 and 91 are positioned respectively adjacent two opposite sides of the container 89. Each nozzle may extend over the full length of the side of the container, or alternatively, a plurality of adjacent nozzles may be provided.

In operation, the knitted fabric F is fed through the work take-off rollers 53 and 54 and, at the appropriate time, the leading end of the knitted fabric is secured by clips 81 in the manner hereinbefore described.

The knitting operation is continued and, when sufficient fabric has been knitted to cause it to take up the vertical, or substantially vertical, position indicated in solid lines in FIG. 12, ajet or jets of compressed air is or are projected through the nozzle or nozzles 90 so that, as knitting progresses, the fabric is neatly positioned in the receptacle. When the fabric F takes up the position indicated in chain dot lines 92 in FIG. 12, the air supply to the nozzle or nozzles 90 is cut and the fabric, as a result of continued knitting, is again allowed to drop under its own weight until it takes up a vertical position as previously described, but in the opposite direction. In this position, compressed air is projected through the nozzle or nozzles 91 to repeat the previously described operation. These operations are carried out alternately until the stacked fabric fills the receptacle when the fabric is cut and a fresh container is positioned in the machine.

It will of course be appreciated that, as the fabric layers build up in the container, the angle and/or height of the nozzles 90, 91 will be varied to ensure that each layer extends the full width or length of the container. The opening and closing of the air valves controlling the supply of air to the nozzles will vary depending upon the type of quality of the fabric being knitted. Overall control will of course be effected from the main control mechanism of the machine in known manner,

The air supply to the nozzles will be provided by a suitable compressor which could be rotated with the container 89. However, the compressor may be stationary and the air transferred to the nozzles via a rotatable pneumatic gland of the type manufactured by Tecalemit Llmited.

Although the invention has been described with respect to a rotating cylinder type of machine, it will be understood that it is not limited in this respect. Thus, the invention can also be applied to a rotating cam box type of machine where the fabric receiving container and other ancillary parts and mechanisms will be stationary.

We claim:

1. Apparatus for use. in combination with a circular knitting machine for stacking knitted fabric in layers in a container in continuation of the knitting thereof, the knitting machine being of the type having supporting framework and elevated work take-off means with a downwardly directed discharge, said apparatus comprising a supporting table for mounting a container within the knitting machine framework below the work take-off means, a container removably carried by said table, guiding means arranged below the work take-off means for directing knitted fabric issuing from the knitting machine into said container, support means mounted on said table for supporting said guiding means, and means for causing said guiding means to impart reciprocal motion to the knitted fabric relative to said container in timed relation to the issuing of the knitted fabric, whereby knitted fabric is folded in concertina fashion and in a uniform manner between two opposite walls of said container.

2. Apparatus according to claim 1, in which said guiding means comprise a pair of fabric layering elements and means mounting said fabric layering elements for horizontal movement and for directly receiving knitted fabric descending from said work take-off means, and said means for. imparting reciprocal motion to the knitted fabric comprise driven means to which opposite ends of said fabric layering elements are coupled, and non-reversible drive means for driving said driven means continuously in one direction.

3. Apparatus according to claim 2, in which said fabric layering elements comprise rollers and means are provided for imparting rotation to said rollers during reciprocal movement thereof.

4. Apparatus according to claim 3, in which said rollers are each mounted on a shaft which projects from opposite ends thereof, said shafts at each end of said rollers being received in a coupling link and having operatively associated therewith spring means which bias said rollers into engagement with one another, coupling of said rollers to said driven means being effected by a drive link extending between said coupling link and said driven means.

5. Apparatus according to claim 4, in which said means for imparting rotation to said rollers comprise a toothed rack positioned to engage gear wheels fixed to said roller shafts, said gear wheels incorporating oneway gears, whereby positive drive will be imparted to one of said rollers during traverse in one direction, and to the other of said rollers, during traverse in the opposite direction.

6. Apparatus according to claim 5, in which said driven means comprise an endless chain whereby, during reversal thereof at the end of a stroke of said rollers, said rollers remain stationary.

7. Apparatus according to claim 6, in which means are provided for effecting continued rotation of said rollers at the end of each stroke, said means comprising a sprocket wheel mounted on the shaft of one of said rollers to engage said endless driven means, said sprocket wheel incorporating a one-way gear whereby drive will be imparted to one of said rollers by movement of said driven means relative to said rollers.

8. Apparatus according to claim 2 wherein said knitting machine is of the type which rotates the fabric as it is knitted in which said supporting table is rotated in synchronism with the knitted fabric and said nonreversible drive means comprise a stationary bevel gear in mesh with a second bevel gear arranged to move with said rotary supporting table and to orbit said stationary bevel gear, said second bevel gear being mounted on, and causing rotation of, a lay shaft from which drive is imparted to said driven means.

9. Apparatus according to claim 8, in which said stationary bevel gear is mounted on the output shaft of a magnetic particle coupling under the control of at least one potentiometer, whereby variable torque is applied to govern the speed of traverse of said fabric layering rollers.

10. Apparatus according to claim 9, in which dropper arms are pivotally supported to extend into said container at positions adjacent each end of the stroke of said fabric layering rollers to hold each fold of said knitted fabric adjacent one wall of said container, cam means being positioned on said roller shafts to raise and lower said dropper arms at the end of each stroke.

11. Apparatus according to claim 1, in which said guiding means comprise a pair of spaced fabric layering elements and means mounting said fabric layering elements for horizontal movement and for directly receiving knitted fabric descending from said work take-off means, and said means for imparting reciprocal motion to the knitted fabric comprise endless driven means to which opposite ends of said layering elements are connected, and reversible drive means for imparting reciprocal motion to said driven means and thus also to said fabric layering elements.

12. Apparatus according to claim 11, wherein said container is open-sided and means are provided for raising said fabric layering elements relative to said container during layering of said knitted fabric.

13. Apparatus according to claim 12, in which said means for raising said fabric layering elements comprise a screw-threaded upright post positioned adjacent each corner of said container, a co-acting bracket member mounted in screw-threaded relationship with each of said screw-threaded posts on which brackets said endless driven means are mounted, and means for rotating all of said screw-threaded posts simultaneously to cause axial movement of said bracket members relative thereto.

14. Apparatus according to claim 13, in which said means for rotating said screw-threaded posts comprise a sprocket wheel fixed to each of said posts, a continuous chain interconnecting said sprocket wheels, a star wheel attached to at least one of said posts, and means for turning said star wheel.

15. Apparatus according to claim 14, wherein said means for turning said star wheel comprise at least one cam which is movable into and out of an operative position, turning of said star wheel being effected by relative movement between said star wheel and said cam.

16. Apparatus according to claim 15, in which operation of said cam is effected by said knitting machine control in synchronism with said knitted fabric output.

17. Apparatus according to claim 15, in which operation of said cam is effected by a sensing device which senses the level of said fabric in said container.

18. Apparatus according to claim 17, in which said sensing device comprises a light source attached to one of said brackets on one side of said container and a photo-electric cell attached to the corresponding bracket on the opposite side of said container.

19. Apparatus according to claim 1, in which said means for guiding said knitted fabric comprise at least one nozzle arranged on each of opposite sides of said container through which compressed air is projected alternately.

20. Apparatus according to claim 19, including means for varying the angular position of said nozzle. 21. Apparatus according to claim 1, wherein said knitting machine is of the type wherein issuing fabric is rotated, bearing means support said table for rotation, and means are connected to said table for rotating said table in unison with issuing knitted fabric.

22. A method of stacking knitted fabric in layers in a container in continuation of the knitting thereof on a circular knitting machine wherein the knitted fabric is delivered downwardly from the knitting machine, which method comprises continuing the downward feeding of said knitted fabric from said knitting machine into said container which is positioned within framework of said knitting machine while imparting generally horizontal reciprocal motion to said fabric to cause it to be folded in concertina fashion, and in a uniform manner between two walls of said container, rotating the knitted fabric as it issues from the knitting machine, and rotating the container in unison with the issuing knitting fabric.

v UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION February 12, 1974 Patent No. 177 Dated Inventor(s) Barry Frederick Swanwick, et al It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In the patent heading, under "Foreign Application Priority Data", "Bulgaria 2,850/71 should read -Great Britain 2, 850/7l- Signed and goaled thisipth day of June 19714..

(SEAL) Attest: v

EDWARD M.FLETCHER, JR. 0'; MARSHALL DANN Attesting Officer Comissioner of Patents USCOMM'DC 6087 6-5 69 FORM PO-1050 (10-69) v: us. uovznumsm PRINTING OFFICE nus o-ase-su,

Claims

1. Apparatus for use in combination with a circular knitting machine for stacking knitted fabric in layers in a container in continuation of the knitting thereof, the knitting machine being of the type having supporting framework and elevated work takeoff means with a downwardly directed discharge, said apparatus comprising a supporting table for mounting a container within the knitting machine framework below the work take-off means, a container removably carried by said table, guiding means arranged below the work take-off means for directing knitted fabric issuing from the knitting machine into said container, support means mounted on said table for supporting said guiding means, and means for causing said guiding means to impart reciprocal motion to the knitted fabric relative to said container in timed relation to the issuing of the knitted fabric, whereby knitted fabric is folded in concertina fashion and in a uniform manner between two opposite walls of said container.

2. Apparatus according to claim 1, in which said guiding means comprise a pair of fabric layering elements and means mounting said fabric layering elements for horizontal movement and for directly receiving knitted fabric descending from said work take-off means, and said means for imparting reciprocal motion to the knitted fabric comprise driven means to which opposite ends of said fabric layering elements are coupled, and non-reversible drive means for driving said driven means continuously in one direction.

5. Apparatus according to claim 4, in which said means for imparting rotation to said rollers comprise a toothed rack positioned to engage gear wheels fixed to said roller shafts, said gear wheels incorporating one-way gears, whereby positive drive will be imparted to one of said rollers during traverse in one direction, and to the other of said rollers, during traverse in the opposite direction.

8. Apparatus according to claim 2 wherein said knitting machine is of the type which rotates the fabric as it is knitted in which said supporting table is rotated in synchronism with the knitted fabric and said non-reversible drive means comprise a stationary bevel gear in mesh with a second bevel gear arranged to move with said rotary supporting table and to orbit said stationary bevel gear, said second bevel gear being mounted on, and causing rotation of, a lay shaft from which drive is imparted to said driven means.

20. Apparatus according to claim 19, including means for varying the angular position of said nozzle.

21. Apparatus according to claim 1, wherein said knitting machine is of the type wherein issuing fabric is rotated, bearing means support said table for rotation, and means are connected to said table for rotating said table in unison with issuing knitted fabric.