The present invention relates to a pile forming apparatus.

FIELD OF THE INVENTION

The present invention provides a pile forming apparatus to form a loop pile or a tuft pile material. Further, the apparatus may be used to form a loop pile or a cut pile over an existing loop pile or cut pile materiaL The former process is referred to as tufting and the latter process is referred to as overtufting.

The processes of tufting and overtufting will hereinafter be referred to as tufting.

In general, a material is tufted by a pile forming apparatus having a needle bar assembly extending the entire width of a material to be tufted. The needle bar assembly has a plurality of needles each supplied with a thread of yarn and associated with a looper and a knife to form a tuft of yarn in the material. Such pile forming apparatus are intended to tuft while travelling along the material in only one direction. No tufting can be carried out on the return pass along the material. ^'

Such pile forming apparatus are suited to producing large amounts of tufted material and are not usually cost effective in producing a small quantity of relatively small tufted material such as floor rugs or door mats.

SUMMARY OF THE INVENTION The present invention provides a pile forming apparatus which can tuft each of two opposite directions along a material.

In accordance with one aspect of the present invention there is provided a pile forming apparatus comprising a sense means for sensing a master pattern and producing a first signal corresponding to the master pattern, a control means for converting the first signal to a corres¬ ponding second signal and for controlling a tuft means according to the second signal such that the tuft means operates to form a pattern corresponding to the master pattern, onto a material. In accordance with a further aspect of the present invention there is provided a method of forming a pattern¬ ed pile on a material, which comprises the steps of sensing a master pattern, producing a first signal corresponding to the master pattern, converting the first signal to a corresponding second signal, and controlling a tuft means according to the second signal such that the tuft means operates to form a pattern, corresponding to the master pattern, onto a material. In accordance with a still further aspect of the present invention there is provided a tuft means comprising a needle, having an eye, arranged to be threaded with a thread of yarn, said needle being arranged to pass the thread of yarn into and through a material, and a looper to collect a loop of the yarn from the eye of the needle to produce a loop of the yarn in the material.

In accordance with a still further aspect of the present invention there is provided a method of tufting a material, which comprises the steps of passing a thread of yarn, in a needle, into and through a material, collecting a loop of the yarn in a hook of a looper and cutting the loop of the yarn with a knife having a cutting blade arranged to pivot on a shaft.

Preferably, the sense means is an optical sense means capable of producing a first signal which is an optical signal and a second signal which is an electrical signal. In such manner the control means is preferably capable of converting the optical signal into an electrical signal which corresponds to the master pattern. Preferably, the looper comprises a hook at an end remote from a mounted end, wherein the remote hook is provided to collect a loop of the yarn. Preferably, a blade of a knife pivots to cut the loop of yarn held by the looper.

The pile forming apparatus of the present invention will hereinafter be described with particular reference to tufting carpet although it is to be understood that it is of general applicability.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will now be described, by way of example, with reference to the accompanying drawings, in whichi-

Figure 1 is a schematic view of a carpet board and boom assembly of the pile forming apparatus in accordance with the present invention; Figure 2 is a plan view of a tuft means for the carpet board and boom assembly of Figure 1;

Figure 3 is a side view of a portion of the tuft means of Figure 2 including drive shafts;.

Figure 4 is a schematic view of a pattern board and further boom assembly of the pile forming apparatus in accordance with the present invention;

Figure 5 is a circuit diagram of a control means of the pile forming apparatus in accordance with the present invention;

Figure 6 is a schematic circuit diagram of a master pattern sensor means of the control means of the pile forming apparatus in accordance with the present invention, shown in relation to the pattern board of Figure 4; Figure 7 is a schematic circuit diagram of a vertical step sensor means of a sensor assembly of the pile forming apparatus in accordance with the present invention; and Figure 8 is a schematic circuit diagram of a co-ordinating means of the pile forming apparatus in accordance with the present invention.

DESCRIPTION OF THE INVENTION

In Figure 1, there is shown a carpet board and boom assembly 9 which comprises a frame 10, formed of a plurality of substantially vertical members 12 and a plurality of substantially horizontal members 14. The frame 10 forms a carpet board 15 and is arranged to provide support to a boom assembly 16. The boom assembly 16 comprises a horizontally moveable carriage 18 and a vertically moveable carriage 20. Roller bearings 22, or the like, are arranged to maintain the horizontally moveable carriage 18 slidably secured to at least two of the horizontal members 14. The roller bearings 22 thus allow the boom assembly 16 to move horizontall . Further roller bearings 23, or the like, are arranged to maintain the vertically moveable carriage 20 slidably secured to the horizontally moveable carriage 18 to

allow the vertically moveable carriage 20 to move vertically.

It is envisaged that the carpet board and boom assembly 9 could be disposed substantially horizontally. In any such case the boom assembly 16 is intended to be moveable along the length of the frame 10.

The frame 10 has mounted on it a horizontal drive assembly 24 comprising a drive motor 26, drive cogs 28a, 28b and 28c and drive chains 30a and 30b. The drive chain 30b of the horizontal drive assembly 24, has its ends secured to the boom assembly 16. The drive chain 30a is endless and engages both cogs 28a and 28b. The cog 28b has a pair of sprockets mounted on a common shaft for rotation together and one sprocket is of larger diameter than the other. The chain 30a passes over the larger diameter sprocket of the cog 28b while the chain 30b passes over the smaller diameter sprocket and the cog 28c. Thus, rotation of the drive cog 28a by the motor 26 causes revolution of the drive chain 30a, rotation of the drive cog 28b and revolution of. the drive chain 30b. This results in horizontal movement of the boom assembly 16. That is, the horizontal drive assembly 24 is provided to move the boom assembly 16 in a substantially horizontal direction, as constrained by the horizontal members 14, along the frame 10.

It is envjaged that the horizontal drive assembly could be any drive assembly capable of moving the boom assembly 16 along the frame 10. The boom assembly 16 has mounted on it a. vertical drive assembly 32 comprising a drive motor 34, drive cogs 36a, 36b and 36c drive chains 38a and 38b. The drive motor 34 and drive cogs 36a and 36b are mounted on the horizontally moveable carriage 18, and the drive chain 38b has its ends

secured to the vertically moveable carriage 20. The drive chain 38a is endless and engages both cogs 36a and

36b.

The cog 36b has a pair of sprockets mounted on a common shaft for rotation together and are sprockets of larger diameter than the other. The chain 38a passes over the larger diameter sprocket of the cog 36b while the chain 38b passes over the smaller diameter sprocket of the cog 36c. Thus, rotation of the drive cog 36a by the motor 34 causes revolution of the drive chain 38a, rotation of the drive cog 36b and revolution of the drive chain 38b. This results in substantially vertical movement of the vertically moveable carriage 20. That is, the vertical drive assembly 32 is provided to raise and lower the vertically moveable carriage 20 in a substantially vertical direction, as constrained by the horizontally moveable carriage 18.

It is envisaged that the vertical drive assembly 32 could be any drive assembly capable of moving the carriage 20 over the boom assembly 16.

Therefore, the horizontal drive assembly 24 and the vertical drive assembly 32 enable the boom assembly 16 to traverse substantially all of the area within the frame 10. More particularly, the horizontal and vertical drive assemblies 24 and 32 enable the boom assembly to traverse at least a part of a carpet held on the carpet board 15 in the frame 10.

Preferably, the horizontal and vertical drive assemblies enable the boom assembly 16 to traverse the entire extent of a piece or part of a roll of carpet held on the carpet board 15.

The vertically moveable carriage 20 provides a moveable platform for a plurality of tufting means 40. As shown in Figures 2 and 3, each tufting means 40 comprises a looper 42, a knife 44 and a needle 46. The looper 42 comprises a loop portion 48 and a base portion 50. The loop portion 48 is arranged to retain a loop of yarn. The base portion 50 is located in a looper holder 52 arranged to secure the looper 42. The loop portion 48 comprises a hook 48a located remotely of the looper holder 52. The hook 48a is intended to retain the loop of yarn.

The looper holder 52 has a pivot 54 which is located remote from the secured looper 42. The pivot 54 allows the looper holder 52 and looper 42 to pivot subject to conditions described hereinafter.

The looper holder 52 is provided with an intermediately located roller bearing 56, or the like. The roller bearing 56 is spring urged outwardly against an eccentric cam 58 mounted on a rotatable cam drive shaft 60. The cam drive shaft 60 drives the eccentric cam 58 and causes the eccentric cam 58 to rotate. The rotation of the eccentric cam 58 causes reciprocal pivoting of the looper holder 52 and the looper 42 about the pivot 54. The knife 44 comprises a knife blade 62 and a cutting edge 64.

A knife holder 66, comprising a clamp 67 is mounted about the knife blade 64 to secure the knife 44. The knife holder 66 has a pivot 68 which is located remote from the securing clamp 67. In a manner similar to the looper holder 52, the knife holder 66 is spring urged so that the roller 70 is urged into contact with a further eccentric cam 71 mounted on

the shaft 60. The knife holder 66 is provided with a lateral extension 69 having a roller 70 at its outer end. The position of the two eccentric cams 58 and 71 about the circumference of the cam drive shaft 60 may be adjusted.

5 The adjustment may be made to effect suitable timing between the pivoting motion of the looper holder 52 and the pivoting motion of the knife holder 66. The required timing is described hereinafter. The tuft means also comprises a needle rod 72 slidably

10 mounted in bearings 74. The needle rod 72 comprises a securing means, such as a threaded bolt 76. The threaded bolt 76 is arranged to secure the needle 46 in a recess 78. The needle rod 72 has pivotally connected to it a first arm 80 situated intermediately of the length of the

15 needle rod 72.

The first arm 80 is pivotally connected to a second arm 82. The second arm 82 is rotatably fixed to an end of a needle drive shaft 84. Upon rotation of the needle drive shaft 84 the second arm

20 82 is caused to rotate about the shaft 84 and produce a corresponding movement in the first arm 80. The first arm 80 then causes reciprocal translation of the needle rod 72 and the needle 46 in the bearings 74. In Figure 1 there is shown a plurality of tuft means 40

25 mounted on the carriage 20.

Each needle drive shaft 84 and each cam drive shaft 60 of the tuft means 40 preferably have a respective timing belt 85 driven by a respective timing shaft 85a. Each timing belt 85 is arranged so that rotation of each

30 needle drive shaft 84 is simultaneous with the rotation of its corresponding cam drive shaft 60 and of synchronous timing.

The boom assembly.16 further comprises a needle looper drive motor 86 having a drive shaft having rotatably mounted thereon a cog 87. The cog 87 engages further rotatable cogs 87a arranged to drive respective timing shafts 85a and timing belts 85. Respective spring wrap clutch assemblies 88 provide communication between the timing shafts 85a and respective pairs of needle drive shafts 84 and cam drive shafts 60. It is envisaged that the needle looper drive motor 86 will have a con- tinuous output via the rotatable cog 87 to the timing shafts 85a. The timing shafts 85a are driven through the spring wrap clutch assemblies 88.

Output from any particular spring wrap clutch assembly 88 may then be subject to energisation of a control solenoid 88a shown in Figure 5, in known manner. Thus, when one of the control solenoids 88a is energised a corresponding tufting means 40 may begin to operate, as described herein. In Figure 4 there is shown a pattern board 90 and a further boom assembly 92.

The further boom assembly 92 comprises a substantially vertical boom 94 slidably secured to substantially horizontal supports 96 and a further horizontal drive assembly 98. The further horizontal drive assembly 98 comprises a drive motor 100, drive cogs 102 and 103 and a drive chain 104.

The drive chain 104 has its ends secured to the boom 94 and passes over the cogs 102 and 103. Thus, rotation of the drive motor 100 produces rotation of the drive cog 102 and 1Q3 and revolution of the drive chain 104 and results in horizontal movement of the boom 94.

The further boom assembly 92 also comprises a further vertical drive assembly 106. The vertical drive assembly 106 comprises a drive motor 108, drive cogs 110 and 111 and a drive chain 112. The drive chain 112 has its ends secured to a vertically moveable carriage 114. The vertically moveable carriage 114 is slidably secured in the boom assembly 92 such that the carriage 114 may be moved in a substantially vertical direction. The carriage 114 is located adjacent the pattern board 90. Thus, rotation of the drive motor 108 produces rotation of the drive cogs 110 and 111 and revolution of the drive chain 112 and results in vertical movement of the carriage 114 on the boom 94. Therefore, the horizontal drive assembly 98 and the vert- ical drive assembly 106 enable the carriage 114 to traverse substantially all of the pattern board 90. The carriage 114 provides a moveable platform for a sensor (described hereinafter) . The sensor produces a first signal corresponding to a pattern on the pattern board 90. Then a control means (described hereinafter) converts the first signal into a corresponding second signal and uses the second signal to control the tuft means 40 such that the tuft means operates to form a scaled version of the pattern onto the material. In fact the pattern board 90 and the further boom assembly 92 are in essence the same as the carpet board and boom assembly 9.

The pattern board 90 is one of a plurality of pattern boards 90 forming a master pattern (not shown) . Each pattern board has associated with it a vertical drive assembly, further boom assembly and carriage. The horizontal drive assembly 98 is arranged to drive all

of the further boom assemblies 92 simultaneously back and forth along the horizontal supports 96.

Further, each pattern board 90 has associated with it one of the plurality of tuft means 40. Thus, each pattern board provides a pattern to which a corresponding tuft means 40 is controlled to tuft the material. It is envisaged that each of the pattern boards 90 at the master pattern provide a pattern for a colour of yarn to be tufted into the material. Thus, for example, a master pattern consisting of five colours, say, would require five pattern boards 90 and five corresponding tuft means 40

Each of the tuft means 40 is independent of the others and it is intended that one pattern board 90 provide pattern for only one tuft means 40.

Movement of the vertical carriage 20 about the carpet board 15, and movement of the carriage 114 about the pattern board 90, is co-ordinated so that a pattern of the pattern board 90 may be reproduced in a pile formed on a material secured on the carpet board 15. The material may be a backing material to be tufted or a tufted material, such as carpet, to be overtufted. More particularly, a co-ordinating means, as described hereinafter, may be provided to co-ordinate the horizontal movement of both the boom assembly 16 and the boom assembly 92. The co-ordinating means may allow the shape of the pattern to be enlarged and reduced in producing the pile. In this way the pattern may be of different dimensions to the pile which is produced. Preferably, the pattern is smaller in area than the material this is tufted therefrom. In Figure 5 there is shown a control means 119 arranged

to variously control the operation of the pile forming apparatus of the present invention. The control means 119 comprises a momentary contact start switch 120 arranged to energise a start relay coil 122a and supply power from a power supply 124, such as a 12V DC power supply, or the like, to the remainder of the control means 119.

The control means 119 also comprises a stop relay 126 comprising a stop relay coil 126a. The stop relay 126 is arranged to interrupt the supply of power from the power supply 124 through a start relay contact 122b via a stop relay contact 126b to the start relay coil 122a, subject to conditions described hereinafter. Once the contacts of the start switch 120 are closed and the start relay coil 122a energised an alternative current path is created via start relay contact 122b, to sustain the energisation of the start relay coil 122. The sustained energisation of the start relay 122, further, directs the supply from the power supply 124 to a switched power supply 128, via a start relay contact 122c, and to the remainder of the control means 119. The control means 119 further comprises a step relay 130 arranged to toggle its contacts between two operational modes when a step relay coil 130a is energised. As a step relay coil 130a is energised, its contacts may toggle from one mode to another, but de-energisation will not affect the operational mode of the contacts. The step relay 130 comprises a step relay contact 130b which is arranged to energise a left horizontal drive relay coil 132a by energising the step relay coil 130a, as described herein. Then a left horizontal drive relay contact 132b may set the horizontal drive assembly 24 and the further horizontal drive assembly 98 to

travel across their respective boom assemblies 16 and 92 in a direction to the left of their present positions. The step relay contact 130b is also arranged to energise a right horizontal drive relay coil 134a by energising the step relay coil 130a, as described herein. Then a right horizontal drive relay contact 134b may set the horizontal drive assembly 24 and the further horizontal drive assembly 98 to travel across their respective boom assemblies 16 and 92 in a direction to the right of their present positions.

The control means 119 is also provided with a yarn sensor 136, which may be a photo transistor or the like. The yarn sensor 136 forms part of a sense means 137 of the present invention. The yarn sensor 136 is connected to an input of a yarn sensor amplifier 138. The yarn sensor amplifier 138 may then control the stop relay coil 126a.

The yarn sensor 136 is arranged to set the yarn sensor amplifier 138 output active and thus activate the stop relay coil 126a, when a thread of yarn in the needle 46 breaks.

The activated stop relay coil 126a may then supply power from the power supply 124, through the stop relay contacts 126c and to the audible alarm 140. Simultaneously, the now switched stop relay contacts 126b de-energise the start relay coil 122a and inhibit operation of the pile forming apparatus of the present invention. It is envisaged that further yarn sensors (not shown) may be provided to operate similarly to the yarn sensor 136 but arranged to confirm the presence of the yarn in

an eye of the needle 46. Further, each tuft means 40. has associated with it a corresponding yarn sensor 136. The control means 119 also comprises an up relay 142, comprising an up relay contact 142b and an up relay coil 142a.

The up relay contact 142b is arranged to de-energise both the left relay coil 132a and the right relay coil 134a, subject to operation of the step relay contacts 130b. More specifically, if, either the left horizontal drive relay coil 132a or the right horizontal drive relay coil 134a are energised, then energisation of the up relay coil 142a will de-energise these relay coils 132a and 134a. The up relay 142 also comprises an up relay contact 142c. The up relay contact 142c is arranged to control the vertical drive motor 36 in an upward direction. The control means also comprises a down relay 144, comprising a down relay contact 144b and a down relay coil 144a. The down relay contact 144b is connected in series with the up relay contact 142b. The down relay contact 144b has a similar effect on the horizontal drive relay coils 132a and 134a as does the up relay contact 142b. Thus, energisation of the up relay coil 142a and/or the down relay coil 144a precludes the energisation of both the left and right horizontal drive relay coils 132a and 134a. The down relay 144 also comprises a down relay contact 144c. The down relay contact 144c is arranged to operate the vertical drive motor 36 in a downward direction.

The control means 119 also comprises a plurality of clutch relays 146 comprising clutch relay coils 146a and clutch relay contacts 146b, only one of the plurality is shown in Figure 5 for reasons of clarity. One of the clutch relay contacts 146b is arranged to energise a corresponding one of the control solenoids 88a of a corresponding one of the spring wrap clutches 88. Each clutch relay coil 146a may become energised if a conduction path is established from the switched power supply 128, through a pattern sensor unit 148 of the sense means 137 (described hereinafter) , through the clutch relay coil 146a, and through an up relay contact 142d, a down relay contact 144d and through either a left or right horizontal drive relay contact 132c or 134c-.

Thus, each clutch relay coil 146a may become energised if both the up and down relay coils 142a and 144a are de-energised and either of the left or right horizontal drive relay coils 132a or 134a are energised, subject to detection of a pattern by the pattern sensor unit 148. The energised clutch relay coil 146a may then cause energisation of the control solenoid 88a corresponding to the pattern sensed. The control solenoid 88a may become energised if a conduction path ^" is established from the switched power supply 128, through the control solenoid 88a, and through down and up relay contacts 144e and 142e and to a negative power supply 150. The. negative power supply 150 is a negative 12V power supply, but could be any suitable non positive supply. Thus, the control solenoid 88a may be energised if the clutch relay coil 146a becomes energised, as described hereinabove, and if neither the down nor the up relay coils 144a or 142a are energised.

Upon energisation a corresponding one of the control sole¬ noids 88a and the corresponding tuft means 40 may perform one tufting cycle, as described hereinafter. The pattern sensor unit 148,. of Figure 5, may comprise any number of pattern sensor units 200, shown in Figure 6, such as five pattern sensor units. Each pattern sensor unit 200 forms a further portion of the sense means 137 of the present invention. The pattern sensor unit 200 comprises a pattern sensor 202 and an operational amplifier 204.

Preferably, the pattern sensor 202 is connected to an input of a comparator 204a and an input of another comparator 204b, of the operational amplifier 204. Each of the pattern sensors 202 are located on the vertically moveable carriages 114 of corresponding further boom assembly 92, shown in Figure 4. Therefore, each of the pattern sensors 202 may be moveably located adjacent corresponding pattern boards 90. The operational amplifier 204 may have two potentiometers 206a and 206b, or the like, connected to further inputs of the comparators 204a and 204b. The pote-±Lometers 206a and 206b may be adjusted to set a voltage level a which a voltage at the input of one of the comparators 204a or 204b may cause the output of the comparator 204a or 204b to become active.

The pattern sensor 202, the comparators 204a and 204b, and the potentiometers 206a and 206b, are thus arranged so that both the comparators 204a and 204b may produce active outputs when the pattern sensor 202 produces a voltage within voltage limits set by the potentiometers 206a and 206b.

The voltage output produced by the pattern sensor 202 is dependent on the colour of a pattern sensed and thus the pattern sensor 202 may be operated to provide a representation of colour and no colour. That is, the sensor 202 can provide a representation of a contrast in colours.

The potentiometers 206a and 206b may be adjusted so that a first range of pattern sensor 202 voltages may set only one comparator 204a or 204b output active. Also, this potentiometer 206a and 206b adjustment may allow a second range of pattern sensor 202 voltages to set the other comparator 204a or 204b output active. Thus, the operational amplifier 204 may be adjusted to give correspondingly active and inactive outputs when the pattern sensors sense a desired colour contrast, corresponding to a pattern sensor 202 voltage within predetermined ranges.

The sensor unit 200 also comprises two opto couplers 208a and 208b, or the like, and amplifier 210 and a control transistor 212, or the like.

The opto couplers 208a and 208b are connected to the output of the comparators 204a and 204b. Outputs of the opto couplers 208a and 208b are arranged to be in series. Thus, the series combination of opto coupler 208a and 208b outputs will conduct only when both comparators 204a and 204b have active outputs.

The series combination of opto coupler 208a and 208b outputs are arranged to control the amplifier 210 , which is arranged to control the control transistor 212. In particular, the control transistor 212 will be caused to conduct when the amplifier 210 output is active. Conduction of the control transistor 212 will establish

a conduction path from the negative power supply 150 to the clutch relay coil 146a, as shown in Figure 5. Therefore, the control transistor 212 will conduct when the pattern sensor 202 senses the desired colour contrast of the pattern, as set by the potentiometers 206a and 206b.

In Figure 7 there is shown a vertical step sensor means 213 of the sense means 137 comprising a vertical step sensor 220, a rotatable disc 222 and a vertical step sensor amplifier 224.

The rotatable disc 222 may comprise any number of sections 226. Preferably, the sections 226 are arranged about the rotatable disc 222 so that adjacent sections 226 are of substantially different colours. The sections 226 may be sectors of a circle, as shown in Figure 7, and may comprise black sections 226a and white sections 226b.

The rotatable disc 222 is arranged to be rotated by a corresponding rotation of a shaft of the drive motor 108 (shown in Figure 4) .

The vertical step sensor 220 is located adjacent the rotatable disc 222, such that the vertical step sensor 220 may sense the differently coloured sections 226a and 226b. The vertical step sensor 220 is connected to inputs of the vertical step amplifier 224. The vertical step amplifier 224 or controlled by a voltage produced by the vertical step sensor 220 in accordance with the co-lour of the coloured sections 226a and 226b. The vertical step amplifier 224 is arranged to have an active output when the vertical step sensor 220 senses, say, a white coloured section 226b. Further, the

vertical step amplifier 224, in this arrangement, may have an inactive output when the vertical step sensor 220 senses, say, a black coloured section 226a. The vertical step amplifier 224 has an output connected to a vertical step relay coil 228a, of a vertical step relay 228, which also comprises a vertical step relay contact 228b.

The vertical step relay coil 228a is arranged to be energised when the vertical step sensor 220 senses a white coloured section 226b. Further, in this arrange¬ ment, the vertical step relay coil 228a may be de-energ¬ ised when the vertical step sensor 220 senses a black coloured section 226a. The vertical step relay contact 228b and a step relay contact 130c, of the step relay 130 shown in Figure 5, are arranged to control a further up relay coil 230a. The further up relay coil 230a may become energised when a conduction path is established from the switched power supply 128, through the vertical step relay contact 228b, through the step relay contact 130c and through the further up relay coil 230a to the negative power supply

150.

When the further up relay coil 230a is energised the further up relay contacts 230b-may set the further vertical drive motor 108 (shown in Figure 4) in an upward direction.

The further vertical drive motor 108 may then cause the rotatable disc 222 to rotate, as described hereinabove. As the rotatable disc 222 is rotated and the coloured section 226 adjacent the vertical step sensor 220 changes from one colour to the other colour the vertical step relay coil 228a may be energised or de-energised to

to interrupt the conduction path supplying power to the further up relay coil 230a.

That is, the drive motor 108 is set to operate vertically until the disc 222 rotates to the next adjacent section 226. Consequently, the vertical drive motor 108 may cease to cause its output shaft to rotate and so cause the rotatable disc 222 to cease rotating. The further up relay coil 230a may then remain de-energised until the step relay contact 130c is switched by momentary energisation of the step relay coil 130 as described hereinafter, to re-establish the conduction path supplying power to the further up relay coil 230a. Re-establishment of the conduction path may cause the rotatable disc 222 to rotate and the conduction path to be further interrupted, as described hereinabove.

The vertical step sensor means 213 controls the width between rows of tufts of yarn. Thus, row width of the pile may be altered by altering the ^' width of and number of the coloured sections 226. It is envisaged that the disc 222 could be replaced by a belt of coloured sections 226. In this manner the row width is readily alterable by only altering the width of the (rectangular) coloured sections 226. The tuft means 40 of the present invention may further comprise a coordinating means 240 to coordinate the relative speeds of the drive motors 26 and 100, shown in Figure 8.

The coordinating means 240 comprises a servomechanism control unit 242 and a horizontal drive motor tachometer generator 244 corresponding to the horizontal drive motor 26 and a further drive motor tachometer generator 246 corresponding to the further horizontal drive motor

100. The servomechanism control unit 242 is connected to the horizontal drive motors 26 and 100 and the corresponding tachometer generators 244 and 246. The connection allows the servomechanism control unit 242 to control the speed of the horizontal drive motors 26 and 100.

The speed control is for the speed of one of the horizontal drive motors 26 or 100 with respect to the other horizontal drive motor 100 or 26. That is, the servomechanism control unit 242 may control the relative speeds of rotatable shafts of the horizontal drive motors 26 and 100 such that the horizontal drive motor 100 may operate at a fractional speed of the horizontal drive motor 26. Therefore, the horizontal length of the pattern on the pattern board 90 may be a fraction of the horizontal length of the -material on the carpet board 15.

The direction of travel of the boom assemblies 16 and 92 is set by the left relay contact 132b and a right relay contact 134b, according to the coordinating means. That is, the left and right relay contacts 132d and 134d set the servo-mechanism control unit to cause the rotatable shafts of the horizontal drive motors 26 and 100 to rotate in one direction or the other. It is understood that different servo-mechanism control units 242 may require different control signals to those hereinabove described.

It is envisaged that a similar servo-mechanism control unit (not shown) could be used to control the vertical drive motors 134 and 108. Thus, the vertical length of the pattern may be a fraction of the. vertical length of the material.

It is further envisaged, that the horizontal drive assemblies 24 and 98 and/or the vertical drive assemblies 32 and 106 could be controlled by the horizontal drive motor 26 and the vertical drive motor 34, respectively. Then pulleys, or the like, could be arranged to drive the further horizontal and vertical drive assemblies 98 and 106 , without the need for further horizontal and/or vertical drive motors 100 and/or 108. Also, those pulleys could affect the speed reduction employed in travel of the further boom assembly 92.

The control means, shown in Figure 5, further comprises a further vertical step sensor assembly corresponding to the carpet board 15. The further vertical step sensor means 151 comprises a rotatable disc 152, a further vertical step sensor 154, a further vertical step amplifier 156 and a further vertical step relay 158.

The further vertical step sensor 154 ^' is located adjacent sectors of the further disc 152. The further vertical step amplifier 156 is arranged to control a further vertical step relay coil 158a.

A further vertical step relay contact 158b and a step relay contact 130d are arranged to energise the up relay coil 142a in manner similar to the energisation of the further up relay coil 230a.

Energisation of the up relay coil 142a will cause the up drive motor 36 to operate and the further disc 152 to rotate. Then when .the coloured sector corresponding to the further vertical step sensor 154 changes the energisation state of the further vertical step relay coil 158a and the up drive motor *36 will cease to operate. The up drive motor 36 may again operate when the step relay 130 toggles to its other mode of operation, that

is, upon reaching the other end of the pattern.

The size of the sectors of the further disc 152 may be altered to alter the distance between consecutively tufted rows. Furthermore, the up drive motor 36 may operate at a speed greater than the further up drive motor 108 so that the vertical dimension of the tufted material may be greater than that of the pattern.

For example, the up drive motor 36 may have a speed three times that of the further up drive motor 108 so that the tufted material will be three times larger vertically than the pattern.

The further vertical step relay 158 also comprises further vertical step contacts 158c and 158d. The further vertical step contacts 158c and 158d may be arranged to control further paralleled carpet board and boom assemblies 9.

The control means 119, shown in Figure 5,-also comprises a vertical searching sensor unit 160, comprising a proximity switch (not shown), and a search sensor 164, such as a photo transistor or the like.

The proximity switch 162 may be a switch that may be activated by the presence of a metallic strip. In this way the vertical searching sensor unit 160 may be energised when a metallic strip, or the like, is sensed.

Then the search sensor 164 is arranged to energise the up relay coil 142a if a suitable vertical line is sensed, such as a black vertical line.

When the vertical line ceases the vertical searching sensor unit 160 will be deactivated and the up drive motor 36 will stop, giving control back to the remainder of the control means 119.

In use, the pile forming apparatus of the present invention may be controlled to produce a tufted material or an over- tufted material in accordance with an optically sensed pattern while the tuft means 40 tufts in both of two opposed directions relative to the material.

The pile forming apparatus of the present invention may be in either of two modes. The tow modes comprise an automatic mode and a manual mode. In the automatic mode the pattern, the sense means 137 and various end limits control the apparatus, and in the manual mode an operator may manually control the apparatus, subject to various end limits.

It is intended that the apparatus of the present invention may have a material such as a backing material or a carpet, which may be secured, by a suitable securing means, in the frame 10 of the carpet board 15 (shown in Figure 1) . Also, patterns may be secured on the pattern boards 90 (shown in Figure 4) . When the material is secured in the frame 10 a first and a second guide plate 250 and 252 (see Figure 2) may be arranged to correspond with the two surfaces of the material.

The distance between the guide plates 250 and 252 may be adjusted to allow for different pile heights of fabric to be treated. The distance from the first guide plate 250 to the eye of the needle 46 may also be adjusted to alter the pile height produced by the apparatus of the present invention. To begin to form a pile in the automatic mode of operation the apparatus of the present invention may be activated by pressing the momentary contact start switch 120. Then, if a thread of yarn is sensed to be present in the needle 46, by the yarn sensor 136, the apparatus may remain activated.

When the apparatus is activated the start relay contact 122c allows power to be supplied from the power supply 124 to the switched supply 128 and to the remainder of the control means 119. If the yarn sensor 136 does not sense the presence of a thread of yarn the control means 119 will be deactivated, by energisation of the stop relay coil 126a, and the audible alarm 140 will be sounded, as controlled by the stop relay contact 126c. Also, the control means 119 may be deactivated by manually pressing a stop switch 254, or an emergency stop switch 255. When the control means 119 is activated the boom assemblies 16 and 92 begin to move in one or two horizontal directions. In the case depicted in Figure 5 the left horizontal drive relay coil 132a may become active and the boom assemblies may begin to move in a direction left of ^" their original position.

The activated left horizontal drive coil 132a causes the left horizontal drive relay contacts 132b to activate the coordinating means 240. The servo-mechanism control unit 242 may then cause the shafts of the horizontal drive motors 26 and 100 to rotate. The rotating shafts will cause the cogs 28a, 28b, 28c and 102 to rotate and the drive chains 30a, 30b and 104 to revolve and consequently the boom assemblies 16 and 92 will move horizontally left.

The distance travelled by the boom assembly 92 will be a fraction of the distance travelled by the boom assembly 16. This fractional distance may be set by adjustment of the coordinating means 240. As the boom assemblies 16 and 92 move left the pattern sensors 202, located adjacent

the master pattern, may detect the presence of a pattern and a voltage may be established at the inputs to the operational amplifiers 204. If the established voltages are between voltage limits set by the potentiometers 206a and 206b, corresponding to a desired colour contrast, the outputs of the comparators 204a and 204b will become active and the control transistors 212 will be turned on. Once the control transistors 212 are turned on and the vertical carriages 20 and 114 are vertically stationary the corresponding clutch relay coils 146a may be energised and a tufting cycle initiated at a corresponding tuft means 40.

The material may be tufted by the tufting means 40 (shown in Figure 3) , arranged on the vertical carriage 20 of the boom assembly 16, when the tufting means 40 is activated.

The tufting means 40 may become active when the pattern sensor 202 detects a pattern and when the boom assemblies 16 and 92 are in horizontal motion, but not in vertical motion.

When the tufting means 40 is activated the needle drive shaft 84 and the cam drive shaft 60 may both be set to rotate by the needle looper drive motor 86 through the rotatable cogs 87a, via the spring wrap clutch assemblies 88 and the timing shafts 85 and the timing belts 85a.

As the needle drive shaft 60 rotates the first and second arms 82 and 80 may move about the axis of rotation of the needle drive shaft 60. The motion of the arms 82 and 80 may lead to a translation of the needle rod 72 and the needle 46 in the bearings 74. The needle 46 translation may be substantially at right angles to the material. In its translation the needle 46 passes through an aperture in the second guide plate 252,

through the material and then through an aperture in the first guide plate 250.

Furthermore, the needle translation has two limiting positions. A first position in which the needle 46 is entirely removed from the material and a second position in which the needle 46 protrudes partly through the material.

When in the second position the looper 42 and looper holder 52 are spring urged against the eccentric cam 58 to a position corresponding the end of the needle 46. In this position the hook 48a passes between the yarn and the needle 46. As the needle 46 retracts toward the first position, the hook 48a retains a loop of yarn. Also, as the needle 46 retracts, the knife holder 66 and knife 44 are forced to pivot about the pivot 68 by the action of the roller bearing 56 being spring urged against the eccentric cam 71 on the cam drive shaft 60. The position of the cam 71, about the circumference of the cam drive shaft 60, with respect to the cam 58, ™ay be such that the knife edge 64 may cut the yarn held by the looper portion 48. In particular, the yarn is cut by the knife edge 64 when the needle rod 72 is substantially at the first position and the needle 46 is stationary. The present arrangement of the needle 46, the knife 44 and the looper 42 will be able to perform tufting cycles while the boom assembly 16 travels in both opposed horizontal directions. To achieve tufting in both horizontal directions the looped thread of yarn is most preferably cut at location A (see Figure 2) of the looper portion 48, that is at the hook 48a.

Whereas, conventional loopers and knives are arranged to cut the looped yarn at location B (see Figure 2) of the looper portion 48 wherein the knife reciprocates to cut the yarn. Thus, conventional tufting means may only tuft in one horizontal direction.

The speed at which the needle 46 passes the yarn through the material is dependent upon the speed at which the boom assembly 16 passes along the material and the rate of delivery of the needle 46 must deliver the loop of yarn through the material in a period of time short enough to ensure that the boom assembly 16 remains substantially stationary with respect to the material. The needle looper drive motor 86 may be driven, for example, at about 1800 rpm in order to achieve a suitably fast needle 46 delivery.

Further tufting cycles may proceed as the pattern sensor unit 148 senses the presence of further-patterns of the master pattern. In any case the boom assembly will continue to proceed left.

The boom assemblies 16 and 92 in the left direction will eventually reach and operate a left hand limit switch 257. The left hand limit switch 257 will become open circuit and prevent the control solenoids 88a, of the spring wrap clutches 88, from becoming energised. Thus, no more tufting cycles will occur while travel is in this direction. However, the boom assemblies 16 and 92 will continue to travel left until the boom assembly 16 reaches a further left hand limit switch 258, shown in Figure 5, having normally open contacts. When the boom assembly reaches the limit switch 258, the limit switch 258 contacts will close and cause the step relay coil 130a to be energised and the left horizontal relay

coil 132a to be de-energised.

The step relay contact 130c will then switch and establish a path for conduction of current to the up relay coil 230a. The energised up relay coil 230a will cause the vertical drive motor 108 to drive the vertical carri ye 114 upwardly. While the up relay coil 142a will be energised and the vertical drive motor 34 set to drive the vertical carriage 20 upwardly. Simultaneously, the rotatable discs 152 and 222 will begin to rotate, as they are driven by the vertical drive motors 34 and 108, respectively. The vertical carriages 20 and 114 will continue to be driven upwardly until the vertical step sensor 154 and 220 detect the next coloured section of the discs 152 and 222. When the next coloured section is sensed the vertical step relay coils 158a and 228a will change from energised to de-energised or vice versa and the vertical step relay contacts 158b and 228b will switch over. The switched vertical step relay contacts 158b and 228b will interrupt the flow of current to the up relay coils 142a and 230a and the vertical drive motors 34 and 108 are stopped.

Energisation of the step relay coil 130a also energises the right horizontal drive relay coil 134a which will cause the boom assemblies 16 and 92 to be driven to the right via the communicating means 240. Tufting cycles will not commence until the left hand limit switch 257 is passed, thus allowing a period of time for the motors 26, 86 and 100 to come up to operating speed. While the boom assemblies 16 and 92 travel right tufting cycles may be performed, as described hereinabove. A delay means is used to provide a delay of approximately

2 seconds as the boom assembly 16 changes direction. This delay corresponds to the delay associated with system response time as the pattern is sensed and a tuft cycle is initiated. The effect of this delay is most pronounced when the horizontal drive motors 26 and 100 are operated at high speeds.

Movement of the boom assemblies 16 and 92 in the right hand direction will eventually reach and operate a right hand limit switch 259. The right hand limit switch 259 will become open circuit and prevent the control solenoids 88a, of the spring wrap clutches 88, from becoming energised.

Thus, no more tufting cycles will occur while travel is in this direction. However, the boom assemblies 16 and 92 will continue to travel right until the boom assembly 16 reaches a further right hand limit switch 260, having normally open contacts. Operation may then proceed similarly to the previous case, where the boom assembly 16 reached the left limit switch 258, excepting that the left horizontal drive relay coil 132a is energised by the step relay 130 and the boom assemblies 16 and 92 begin to travel left again. As the height of the vertical carriages 20 and 114 increase an up limit switch 262 will eventually be reached and switched to open circuit. Upon switching, the up limit switch 262 will de-energise the up relay coil 142a, and the carriages 20 and 114 and boom assemb¬ lies 16 and 92 will stop. If the boom assembly 16 does travel past the'left or right limit switches 258 or 260, ultimate left and right limit switches 263 and 264 are provided to de-energise

the left or right horizontal drive relay coil 132a or 134a, respectively, and prevent further horizontal motion. A horizontal drive motor overload switch 272 is provided to de-energise the start relay coil 122a in response to an overload condition occurring in the horizontal drive motor 26.

The de-energised start relay coil 122a will in turn deactivate the remainder of the control means 119. When the remainder of the control means 119 is deactivated the tufting apparatus of the present invention may be operated in a manual mode.

In the manual mode of operation the boom assemblies 16 and 92 may be driven horizontally left or right by a manual left switch 264 and a manual right switch 266.

In this mode movement of the boom carriages 16 and 92 is subject to the limit switches 257, 258, 259 and 260, as before and dependent on left and right horizontal relays 132 and 134, and the communicating means 240. There is also provided a manual up switch 268 and a manual down switch 270 to manually control the vertical carriages 20 and 114 in a vertical direction. Control vertically upward is subject to the vertical step assemblies while control vertically downward is continuous. The up limit switch 262 and a down limit switch 274 set the ultimate vertical travel of the vertical carriages 20 and 114.

The control means is preferably arranged so that tufting cycles may not be performed when the apparatus is operated in the manual mode.

It is envisaged that the tufting apparatus of the present invention could comprise any number of carpet board and

-boom assemblies 9, arranged in parallel. In this manner several frames of material could be tufted simultaneously to the same pattern. It is also envisaged that the vertical step sensor means 151 and 222 could be replaced with times arranged to drive the boom assemblies 16 and 92 upwardly for a pre-set time.

It is further envisaged that the optical sensors could be optical fibre sensors. In such manner the aste-. pattern could be substantially smaller than the pile formed corresponding thereto..

It is still further envisaged that the apparatus of the present invention could be controlled by a computer or a programmable logic controller or the like. It is still further envisaged that a breaking means be applied to each yarn to hold the yarn stationary in the needle 46 as the needle 46 retracts from the material and the yarn is cut. Modifications and variations such as would be apparent to a skilled addressee are deemed within the scope of the present invention. For example, the control means could be any control means that could give control similar to that described hereinabove. Also, any or all of the limit switches 257, 258, 259, 260, 262, 264, 266, 268, 270 and 272 could be replaced if a control means that could measure distance travelled, is used. Furthermore, whilst the carpet board of the present . . invention is rectangular it is envisaged that other shaped carpet boards could be used, such as circular. Still further, the vertical drive motors 36 and 108 could be stepper motors so that a predetermined number of pulses could be used to drive the carriages 20 and 114 upward.