GB2089462A

GB2089462A - Foil tube winding machine

Info

Publication number: GB2089462A
Application number: GB8136904A
Authority: GB
Original assignee: Christian Majer & Co KG GmbH; Christian Majer GmbH and Co KG Maschinenfabrik
Current assignee: Christian Majer & Co KG GmbH; Christian Majer GmbH and Co KG Maschinenfabrik
Priority date: 1980-12-12
Filing date: 1981-12-08
Publication date: 1982-06-23
Also published as: FR2495998A1; DE3046752C2; DE3046752A1; FR2495998B3; GB2089462B

Abstract

Control of the severance of predetermined lengths from a spirally- wound tube 10, as the latter is being wound, is achieved by the tube 10 rotating a fluted roller 12, on which it rests, to cause impulse transmitter 14 to supply impulses to a stepping motor 25, by way of a regulating stage 22. Motor 25 displaces carriage 20 (carrying a cutter) in synchronism with movement of the tube 10 for severing the latter, and after severance the carriage 20 returns to an initial position. <IMAGE>

Description

SPECIFICATION Foil tube winding machine This invention relates to a continuouslyoperating foil tube winding machine (that is to say a winding machine for winding foil strip into tubes), more especially a spiral winding machine, having an arrangement for controlling a carriage which can be displaced forwards and backwards in the feed (or advance) direction of the wound tube and which carries a cutting device.

Arrangements of this kind are already known.

Particular problems arise, in this respect, in controlling the carriage, carrying the cutting device, in synchronism with the tube movement (see, for example, German Offenlegungsschrift No.

24 28 219). It has already been proposed to determine the tube portions, to be cut to length, by measuring the length of the foil strips running to the winding location (see German Patent Specification No. 27 24 899 and German Patent Specification No. 875 914).

The problem underlying the invention is to provide a control arrangement of this kind which is significantly simplified without its reliability suffering therefrom.

The problem posed is solved, in a machine of the kind mentioned at the introduction hereof, in accordance with the invention, in that the control arrangement has a signal transmitter which is coupled to a roller which is rotatable by the feed movement of the wound tube thereon, and in the signal transmitter is coupled to a control unit which controls the carriage movement as a function of the transmitter signal and contains a counting stage which receives the transmitter signal and which triggers the cutting device.

In the arrangement in accordance with the ~invention, therefore, the feed movement of the wound tube is detected and both the simultaneous running movement of the carriage carrying the cutting device and the use of the cutting member of the cutting device are controlled by this feed movement. It was not obvious, in the control, to make a start from the longitudinal movement of the wound tube, because the winding tube performs not only a longitudinal movement, but also a rotary movement, which makes exact measurement of the longitudinal movement of the tube problematical. Practice shows that a roller having a smooth surface is not suitable for deducing the longitudinal movement of the supported wound tube which is at the same time carrying out a rotary movement.Only by providing a fluting, more particularly an axially-parallel fluting, on the roller has it been possible to achieve the result of detecting axially the longitudinal movement with no slippage of the roller occurring through the simultaneous rotary movement of the wound tube.

Advantageously an impulse transmitter, which is coupled to a counter, is connected as signal transmitter to the roller which deduces the tube movement. By counting the impulses supplied, the length of the wound tube moved in each case over the roller can be determined and, by comparison with a present desired value, the use of the cutting member of the cutting device for severing a portion of the winding tube, of desired length, can be controlled. From the frequency of the impulses supplied by the impulse transmitter, the adjusting movement of the carriage can be synchronised with the feed movement of the winding tube, in which respect the impulses can be utilised in impulse form or may be converted into an analogue signal, for the carriage drive.However, a conventional tachogenerator could be used, as signal transmitter, from the output signal of which impulses can be ascertained for the length determination by way of an analogue/digital converter.

Three exemplified embodiments of the invention will now be described, in more detail, with reference to the accompanying drawings, in which:~ Fig. 1 is a schematic perspective representation of the signal transmitter in conjunction with a block diagram of the remaining control arrangement in a first embodiment of the invention; Fig. 2 is a view, similar to Fig. 1, of a second exemplified embodiment of the control arrangement; Fig. 3 is a view, similar to Figs. 1 and 2, of a third exemplified embodiment of the control arrangement.

Referring firstly to Fig. 1, a spirally-wound tube 10 rests on a roller 11 which is provided with axially-parallel fluting 12. Shaft 13 of the roller 11 is connected to an impulse transmitter 14 which may be of known construction. Axial displacement of the winding tube 10 causes rotation of the roller 11, and this rotary movement triggers impulses in the impulse transmitter 14 which impulses are transmitted, by way of an output line 15 and a second branch line 16, to a preselection counter 17.The preselection counter 17 is connected to an intermediate logic stage 18 which, after reaching a specific, preset impulse count corresponding to a specific displacement length of the tube 10, supplies to an output line 29 a triggering command for a cutting member (not shown) which is arranged on a carriage 20, which is indicated only schematically in the drawing, of the cutting device.

By way of a second branch line or wire 21, the impulses, supplied by the impulse transmitter 14, pass to a regulating stage 22 which, by way of two output lines 23 and 24, supplies switching impulses to a stepping motor 25 which serves to drive the carriage 20. The drive is achieved by means of a pinion 27 which is fitted onto the motor shaft 26 and which engages with a rack 28 fastened to the carriage 20. The carriage 20 is moved, in a manner which is not evident from the drawing, parallel to the lap tube 10 and, in so doing, by means of the control arrangement, is caused to move synchronously with the longitudinal movement of the tube 10. In the opposite direction a restoring movement takes place at increased speed to return the carriage 20 into an initial position.This restoring movement is controlled by the intermediate logic stage 18 by way of the line 29 leading to the regulating stage 22, and the regulating stage 22 brings about, by way of a line 30, reversal of the direction of a rotation of, and high-speed movement of the stepping motor 25.

The desired tube portion length corresponds to a specific impulse count from the impluse transmitter 14. This impulse count is fed as desired or nominal value into the control arrangment. As soon as the preselection counter 1 7 has reached this impulse count, by way of the intermediate logic stage 18 the cutting member (not shown) present on the carriage 20 is actuated to sever the portion of tube from the winding tube 10. After the severance of the wound tube portion which has been effected, in the case of the stepping motor 25 synchronised by impulses supplied by the impulse transmitter, in synchronism with the feed movement of the winding tube 10, the stepping motor 25 is switched-over in its drive direction, and with an impulse count which is independent of the impulse transmitter 14, rotates back rapidly to the initial position.During this time, in the preselection counter 17 the non-interrupted feed movement of the winding tube 10 is already detected once again.

In the embodiment in accordance with Fig. 2, a hydraulic motor 31 is provided instead of a stepping motor 25 for driving the carriage 20, which motor 31 is driven, by way of a valve unit 32 controlled by regulating stage 22', synchronously with the movement of the winding tube 10. In this circuit, a digital/analogue converter 33 is connected into the branch line 21.

Connected to the hydraulic motor is a tachogenerator 34 which, by way of the control line 30, supplies an actual-valve signal to the regulating stage 22' which is compared with the analogue signals arriving by way of the output line 35 of the digital/analogue converter 33.

In the exemplified embodiment in accordance with Fig. 3, tachogenerator 36 is provided as signal transmitter, instead of the impulse transmitter 14, which supplies an analogue signal to the output line 15. Connected into the connecting branch line 1 6 is an analogue/digital converter 37 which, by way of an output line 38, supplies impulses to the preselection counter 17 which is effective, in the manner already described, by way of the intermediate stage 1 8. By way of the branch line 21, the analogue signal of the tachogenerator (or tacho-alternator) 36 passes directly to an input of the regulating stage 22', which has the-same form as in the case of the exemplified embodiment in accordance with Fig. 2, because here, too, a hydraulic motor 31 for the synchronous drive of the carriage 20 is provided.

Claims

1. A continuously-operating foil tube winding machine, more especially a spiral machine having an arrangement for controlling a carriage which can be displaced forwards and backwards in the feed direction of the wound tube and which carries a cutting device, characterised in that the control arrangement comprises a signal transmitter which is coupled to a fluted roller which is rotatable by the wound tube resting thereon, and in that the signal transmitter is coupled to a control unit which controls the movement of the carriage as affunction of the transmitter signal and contains a counting stage which receives the transmitter signal and triggers the cutting device.

2. A machine as claimed in claim 1, characterised in that the roller has axially-parallel fluting.

3. A machine as claimed in claim 1, 2, characterised in that the signal transmitter is an impulse transmitter which is coupled to a counter and the impulses of which control a stepping motor for the drive of the carriage.

4. A machine as claimed in claim 1, 2 or 3, characterised in that connected subsequent to the impulse transmitter is a digital/analogue converter the output analogue signal of which controls the carriage drive in the tube feed direction.

5. A continuously-operating foil tube winding machine having a control arrangement substantially as hereinbefore described with reference to and as illustrated in Fig. 1, in Fig. 2 or in Fig. 3 of the accompanying drawings.