GB2136152A - A Device for the Electronic Control of Flat Circular Knitting Machines - Google Patents

Abstract

A device for the electronic control of flat circular knitting machines of the type having at least one needle bed pair, with carriages circulating after one another in one direction and a micro-computer control, in which the micro-computer control (6) is disposed in a compact housing (7) which is disposed in a rotatable manner centrally to the path of circulation of the carriages (2), wherein the housing (7) is driven synchronously with the movement of the carriages (2) and each carriage (2) is connected via a trailing cable (10) with the micro-computer control (6). <IMAGE>

Description

SPECIFICATION A Device for the Electronic Control of Flat Circular Knitting Machines A device for the electronic control of a flat circular knitting machine of the type (hereinafter referred to as the type set forth) having at least one pair of needle beds, having carriages rotating consecutively in one direction and a microcomputer control.

A flat knitting machine with pairs of needle beds disposed one after the other and rotating cam carriages each having a pattern wheel and stationary electromagnetic control members disposed between the pairs of needle beds for transmitting the pattern or control signals from a fixed micro-computer control unit located outside of the flat knitting machine to the cam carriages is known (East German Patent Specification 1 58 484). The drawback of this flat knitting machine is the limited pattern repeat caused by the use of mechanical pattern wheels.It has been attempted to counter these drawbacks, in the case of a flat knitting machine of the type described above, by dividing the control members for Jacquard information into two groups and guiding these in alternating directions along a respective path branching off from the carriage path in the area of the pattern bases of the pivoting sinkers on the needle bed, wherein the control members are actuated by a fixed control unit in accordance with the pattern via trailing cables which are known per se (East German Patent Specification 141 175). The high costs incurred as a result of the use and the operation of changeable control member groups is disadvantageous in this respect.In addition, conventional lift carriage flat knitting machines are known, in which each needle or its striker is associated with an individual magnet, which is controlled by a fixed micro-computer control disposed externally to the machine (East German Patent Specification 24031; West German Patent Specification 1 635 968). The number of control magnets used makes these flat knitting machines both costly and liable to malfunction.For this reason, electronically controlled conventional lift carriage flat knitting machines have become known, in which a few electromagnetic control members for needle selection are disposed on the carriage of the machine (West German Patent Specification 2 010 973) or on a support which may be displaced parallel to the carriage (US Patent Specification 3 867 820), which members may be controlled in accordance with the pattern by a fixed control unit via a respective trailing cable. This control of the control members using trailing cables has appeared to be impossible, or only possible with considerable expenditure, up to now for the control of a plurality of control members on several cam carriages which rotate on two needle bed pairs disposed one after the other.The East German Patent Specification 211066 therefore discloses a solution for guiding the trailing cables rotating with control member supports, which proposes a switchback path guide with switch points which is costly in terms of material and requires a great deal of space. It was therefore attempted to control the control members rotating with the carriages via sliding contacts on the carriages. As this transmission led to problems with the control signals as a result of soiling or disturbances within the transmission (German Offenlegungsschrift 2 658 588), this method was not successful.The wireless transmission between fixed transmitters and movable receivers on the rotating carriages (West German Patent Specifications 2 060 942, 2 114 013 and 2 658 588) using electro-optic, acoustic or screened directional electromagnetic methods is not only extremely costly, but also subject to malfunction (West German Patent Specification 2 658 588) and requires special protection against interference.

The invention is directed to the provision of a simple electronic control for the flat knitting machine which is not subject to any great extent to malfunction and to improve the transmission of data between the micro-computer and the control members rotating with the carriages.

According to the present invention, there is provided a device for the electronic control of a fiat circular knitting machine of the type set forth, wherein the micro-computer control is disposed in a compact housing, which is disposed in a rotatable manner on the circular knitting machine centrally to the guideway of the carriages, in that the housing is driven synchronously with the movement of the card ages and in that each carriage is connected with the micro-computer control via a trailing cable.

The invention wili be more fully understood from the following description given by way of example only with reference to the figures of the accompanying drawings in which: Figure 1 is a diagrammatic illustration of the control of a flat circular knitting machine, Figure 2 is a block circuit diagram of a microcomputer control.

In Figure 1 a closed guideway 1 of a Jacquard flat circular knitting machine has carriages 2 that are guided on this guideway, which carriages are provided with the knitting systems in a known manner, which are not shown. The carriages 2 circulate continuously on the guideway 1, via the two needle bed pairs 3,4 in the direction of the arrow. The drive is provided in a known manner via a chain drive 5. Micro-computer control 6 is disposed in the centre of the guideway 1. The micro-computer control is disposed in a compact housing 7 which is rotatably disposed on the frame 8. The micro-computer control 6 is driven synchronously with the movement of the carriages 2, via a chain drive 9, by the main drive of the machine. The micro-computer control 6 is connected with each carriage 2 via a trailing cable 10.A length compensator 11 is disposed on each carriage 2, which compensator, in the same way as known cable take-up devices, compensates the different lengths of the trailing cable in the case of rotation. The micro-computer control 6, which is disposed in the housing 7, comprises the central processing unit 12 (CPU). The CPU 12 is connected via the address bus 13 and the data bus 1 6 with a ROM memory 14, which contains the operating programme for the micro-computer control 16, with a RAM memory 15 which contains the pattern programme and with both input unit 1 7 and output unit 1 8. In addition the microcomputer control 6 comprises a timing generator 19 and a power supply 20. The output unit 18 is connected via an amplifier 21 and a group of output lines 22 with control member section 23 of each carriage 2.The control member section 23 comprises the control members for the displacement functions, for the switching functions of the known flat circular Jacquard machines (i.e. cam position, rigidity, thread guide, pressure strip, loop transfer components) and for the Jacquard functions. The formation of control members of this type is known and is not described in detail here. The transmission of the electrical power required for the operation of the micro-computer control 6 takes place in the moving system by means of slip ring system 24 which is rotatably connected with the housing 7 of the micro-computer control 6. In the same way the on/off signal for the machine drive is supplied via the slip ring system 24.In addition, each carriage 2 is provided with a needle pulse initiator 25 which is connected via line 26 with the input unit 1 7. Each carriage 2 further supports an initiator strip 27 which carries the initiators 28 for the displacement functions, the initiators 29, 30 for the switching functions and the initiators 31, 32 for the Jacquard functions. Each initiator 28 to 32 is connected via a line 33 to 37 with the input unit 17.Each carriage 2 is provided, in addition to the initiators 28 to 32, with signal transmitters in a known manner which are not shown, for thread breakage, needle breakage, knot detection, which transmitters are connected via a respective line with the input unit 1 7. A signal tappet 38 which moves downwardly into the slot of the initiators 28 to 32 is disposed on the guideway 1, between the needle bed pairs 3, 4 in the area of movement of each initiator 28 to 32:'Slot initiators are used for the initiators 28 to 32. Other known methods of electrical signal production may be used instead of these slot initiators.

During operation, the initiators 28 to 32 are arranged to produce an input signal when each carriage 2 passes a signal tappet 38, which signal is subsequently supplied to the lines 33 to 37 of the input unit and therefore to the micro computer control 6. The micro-computer control is therefore caused to transmit, in the manner disclosed in East German Patent Specification 158 484, the displacement, switching and Jacquard functions to the control members of the control member section 23. The transmission of the displacement and switching signals is terminated before the carriage 2, to be programmed, enters the needle. bed pair 3. The transmission of the Jacquard signals commences when the needle pulse initiator 25 moves with each carriage 2 into the needle bed pair 3 or 4 in the needle sequence and is discontinued on leaving these needle bed pairs 3 and 4. The needle pulse signals of the needle pulse initiator 25 are supplied via the line 26 to the input unit 1 7. The input of the required knitting data into the micro-computer control 6 takes place when the machine is stationary, for example by plugging in a portable perforated strip reader or a like data input device.

Claims (6)

1. A device for the electronic control of a flat circular knitting machine of the type set forth, wherein the micro-computer control is disposed in a compact housing, which is disposed in a rotatable manner on the circular knitting machine centrally to the guideway of the carriages, in that the housing is driven synchronously with the movement of the carriages and in that each carriage is connected with the micro-computer control via a trailing cable.

2. The device as claimed in claim 1, wherein the input unit, the output unit, the central processing unit, the ROM memory, the RAM memory, the timing generator, the amplifier and the power supply are disposed in the rotatable housing of the micro-computer control, wherein the housing and a slip ring system are connected together coaxially and rotatably.

3. The device as claimed in claims 1 and 2, wherein on each carriage the control member sections for all the switching and Jacquard functions are connected via the output lines and the amplifier with the output unit of the microcomputer control, in that a needle pulse initiator is connected via a line with the input unit and the initiators for the displacement, switching and Jacquard functions are connected via the lines with the input unit.

4. The device as claimed in claims 1 to 3, wherein a length compensator for the trailing cable supplied is disposed on each carriage.

5. The device as claimed in claims 1 to 3, wherein each carriage comprises an initiator strip on which the initiators are consecutively disposed in the direction of circulation of the carriages.

6. A device for the electronic control of flat circular knitting machines of the type set forth, said device being constructed and arranged substantially as hereinbefore described and as shown in the figures of the accompanying drawings.