EP0391453B1 - Device for winding and unwinding printed products transported on a conveyor - Google Patents

Abstract

A driven and vertically adjustable winding core (19) and a supply reel (33) for dispensing or receiving a winding band (34) to be wound on or off with the flat products (Z) are provided as well as a conveyor (16) for supplying or removing the flat products (Z) to be wound on or off. Provided between the conveyor (16) and the winding core (19) is a conveyor belt arrangement (14) which feeds or guides away the flat products (Z) and the winding band (34). In order to reduce the space requirement of the device and to simplify its drive systems while still ensuring satisfactory winding-on or winding-off, the conveyor belt arrangement (14) is designed to rotate freely and partially loops around the winding core (19) or the roll (W) thereon with spring action, the driving elements (20, 21) for the winding core (19) protruding from a vertically guided, displaceable carriage which can be raised and lowered by means of a lifting drive (24, 25) controllable by the moment application of the conveyor belt arrangement (14). <IMAGE>

Description

The present invention relates to a device according to the preamble of claim 1.

Such a device is known from DE-OS 31 23 888. An essential element of the known device is the deflection roller, via which the winding tape runs from the supply reel to the winding or vice versa. In the known device, this deflecting roller is driven positively so that its peripheral speed is equal to the conveying speed of the shingled stream, this deflecting roller determining the peripheral speed of the roll and, consequently, its speed both during winding and during unwinding. In the known device, the winding core is driven during winding via a winding gear which tends to drive the winding core in such a way that the peripheral speed of the winding leads the conveying speed of the shingled stream. The result of this is that the winding tape between the deflecting roller and the run-up point on the winding is under a tensile stress, which causes a slight, however, elongation of the winding tape and is wound up in this state.

In order to avoid the winding mechanism of the above-mentioned known device, another comparable device has become known from DE-OS 33 45 191. Here the winding core is driven by an electric control motor driven, the speed of which is calculated from the feed rate of the shingled stream and the current winding diameter. In this further known device, the winding tape is advanced (with braking) in such a way that its speed is continuously adapted to the feeding speed without the tension in the winding tape changing during the acceleration or deceleration phases.

In this prior art, it is an object of the invention to improve a device of the type mentioned at the outset such that a length of the winding tape corresponding to the length of the wound (or unwound) scale formation is wound (or unwound), this winding tape length not increasing a (calculated) target speed of the winding is determined, but conversely the winding is driven at such a speed that the actual consumption of winding tape is achieved regardless of the constriction on the circumference of the winding generated by the tension of the winding tape.

Accordingly, the proposed device has the features specified in the characterizing part of claim 1.

It follows that the proposed device, starting from that of DE-OS 31 23 888, goes the diametrically opposite way in comparison to the device according to DE-OS 33 45 191.

In addition, the fact that the peripheral speed of the winding - measured on the winding belt - is exactly the conveying speed is remarkable in the proposed device corresponds to the shingled stream, since the winding tape as a whole is stretched between the supply reel and the winding, that is to say it runs onto the deflection roller in the stretched state. On the other hand, since the actual "tape consumption" represents the actual size, in particular when winding up, and a desired consumption of winding tape is aimed at via the speed of the control motor, the constriction of the winding caused by the winding tape is compensated for by a corresponding increase in the drive speed of the winding core.

Features of preferred embodiments can be found in the dependent claims.

• Fig. 1 eine schematische Ansicht einer Einrichtung;
• Fig. 2 eine Ansicht aus Richtung des Pfeiles II der Fig. 1, wobei die linke Hälfte etwa einem Schnitt A-A entspricht und
• Fig. 3 eine schematische Darstellung der Antriebe der Fig. 1 und deren Steuerglieder.

Further advantages of the proposed device result from the subsequent description of an embodiment with reference to the drawing. It shows:

• Fig. 1 is a schematic view of a device;
• Fig. 2 is a view from the direction of arrow II of FIG. 1, the left half corresponds approximately to a section AA and
• Fig. 3 is a schematic representation of the drives of Fig. 1 and their control elements.

The device 10 shown in the drawing has a base 11 on which, on the one hand, two upright guide columns 12, 13 are anchored and, on the other hand, a conveyor belt arrangement 14, only shown schematically, is mounted. The deflection roller 15 of the conveyor belt arrangement 14 connects to a conveyor 16, of which only the end or the beginning (depending on whether winding or unwinding) is shown in FIGS. 1 and 3.

Between the two guide columns 12, 13, a carriage or carriage 18 is mounted, which is displaceably guided by rollers 17 and from which the drive members for an essentially hollow cylindrical winding core 19 protrude. These drive members comprise two drive wheels 20, 21 which drive the winding core 19 from the inside in a frictional engagement, and a freely rotatably mounted tensioning roller 22 which holds the winding core 19 in contact with the drive wheels 20, 21 EP OS 0161569 described in detail. However, it goes without saying that a differently designed drive for the winding core, which does not necessarily have to be hollow cylindrical, can also be provided.

A nut piece 23 (FIG. 2) is anchored on the carriage 18 and is penetrated by a threaded spindle 24 parallel to the guide columns 12, 13. The threaded spindle 24 can be driven by means of a stationary, for example on the guide columns 12, 13, only schematically indicated motor 25, so that the motor 18 of the carriage 18 can be practically steplessly moved and held over the entire height of the guide columns 12, 13 .

A motor 26 flanged to the carriage 18 is coupled to the drive wheel 21, while the drive wheel 20 is positively coupled to the drive wheel 21 via a chain drive 27.

The conveyor belt arrangement 14 is arranged in a frame 28, indicated only schematically in FIG. 1, which is pivotally mounted about the axis of the deflection roller 15 and carries a further deflection roller 29 at its end which appears on the right in FIG. 1. The two deflection rollers 15 and 29 are freely rotatably supported and looped around by a pair of comparatively slack conveyor belts 30, 31 (FIG. 2). Between the deflecting rollers 15 and 29 and between the conveyor belts 30, 31, a further deflecting roller 32 is freely rotatably mounted on the frame 28 in a manner not shown, which has a winding belt 34 pulled off a supply roller 33 or wound onto it and guided over the deflecting roller 29 brings to the height of the upper run of the conveyor belts 30, 31 and runs in the same direction with them.

The frame 28 and thus the conveyor belts 30, 31 and also the winding belt 34 are pushed upwards by means of a spring 35, for example a gas spring, so that the comparatively slack conveyor belts 30, 31 are pressed against the circumference of the winding W located on the winding core 19 and wrap it over a comparatively large arc length. If the winding W is driven via the winding core 19 in one or the other direction of rotation, the conveyor belts 30, 31 thus run along and the winding belt 34 is pulled off the supply roll 33 or wound onto it.

For this purpose, the supply roll 33 is positively coupled via a chain drive 36 to a torque-controlled machine 37, which will be returned in particular in connection with FIG. 3. It follows from the above description that the device is suitable for producing coils of the most varied diameters, and in addition finished coils W, regardless of their diameter, can be raised by means of the threaded spindle 24 to such an extent that they can be pulled through from the side opposite the carriage 18 ( 2 from the right) transport vehicle (for example by a forklift) can be removed from the drive wheels 20, 21 and the tensioning roller 22 and transported to an intermediate storage location. In Fig. 1 the bottom and top positions of the winding core 19 can be seen with dash-dotted circles. The direction of rotation of the winding W is indicated by the arrow 38 when winding and the arrow 39 indicates that when it is being unwound.

FIG. 3 largely corresponds to FIG. 1, but in this FIG. 3 a block diagram of the electrical circuit is superimposed. In this figure, the symbol M 1 corresponds to the motor 26, the symbol M 3 to the motor 25 and the symbol M 2 to the torque-controlled machine 37.

A transmitter 40, for example a tachometer generator, is coupled to the illustrated deflection roller of the conveyor 16, which generates a “target” signal relating to the speed and the conveying direction of the conveyor 16. This signal reaches a comparator and feed stage 42 via a line 41.

A transmitter 43 is also coupled to the deflection roller 32 for the winding tape 34, which generates an “actual” signal with respect to the actual peripheral speed and the direction of rotation of the winding W. This actual signal is fed via a line 44 to the comparator and feed stage 42. In accordance with the difference signal determined in the stage 42, this controls the motor 26 (M 1) via a feed line 45 in such a way that the rotational speed at which it drives the winding core 19 leads to a peripheral speed of the winding W, which with respect to the direction and speed of that of the Conveyor 16 corresponds. For this purpose, the motor 26 (M 1) can be a reversible DC machine or a frequency-controlled pole-changing asynchronous motor. The conveyor belt arrangement 14 is assigned two buttons 46, 47, for example light barriers, which detect the momentary installation of the upper run of the conveyor belts 30, 31. If the button 47 responds, the motor 25 (M 3) of the threaded spindle 24 is switched on via the line 48 in the sense of lifting the carriage 18 (and thus the roll W) and remains switched on (when winding up) until the button 46 appeals. When the roll W is unwound, the buttons 46, 47 swap their roles. The motor 25 (M 3) can, however, also be switched on and off via a switch 49, which is only indicated schematically and bridges the buttons 46, 47. A reversible and pole-changing asynchronous machine has proven to be expedient for the motor 25 (M 3). The motor 25 (M 3) is switched on via the switch 49 when a finished roll has to be raised to the highest position for takeover by a transport vehicle (as mentioned) or when an empty roll core 19 has to be lowered so far that it touches the conveyor belt arrangement 14 .

The winding tape 34 is kept under as constant a tension as possible when winding the winding W. Therefore, the supply roll 33 is to be braked in accordance with its own diameter so that the winding tape receives the desired tension (and elongation) between the run-off point from the supply roll 33 and the run-up point on the roll W. The braking torque to be exerted on the supply roll 33 is of course dependent on its current diameter. Therefore, the supply roll 33 is assigned a diameter sensor 50 which controls the torque-controlled machine 37 (M 2) via a control line 51 and a control stage 52. This torque-controlled machine 37 (M 2) is expediently a torque-controlled servo DC machine which can be switched both as a motor (drive) and as a generator (brake).

When the reel W (arrow 39) is unwound, the direction of rotation of the machine 37 (M 2) is reversed, so that it drives the supply roll 33, possibly via a slip clutch (not shown), approximately as the receiving reel of a magnetic tape cassette, which means that liberated winding belt 34 is fed back onto the supply roll 33, while the flat structures Z reach the conveyor 16 via the conveyor belt arrangement 14.

Claims (7)

1. A device for winding and unwinding flat articles (Z), in particular printed items in overlapping array, which by means of a conveyor (16), are being fed to or discharged from a roll (W), with a roll hub (19) and with a winding strip (34) to be wound or unwound with the flat articles (Z) which extends from a supply spool (33) over a deflection roller (32) rotating at its periphery at the same speed as the conveyor (16) to the roll hub (19), or as the case may be from the roll (W), the roll hub (19) being respectively driven or braked while the supply spool (33) is respectively braked or driven, characterized in that the roll hub (19) is coupled to an electric variable speed motor (26, M1) and the hub of the supply spool (33) is coupled to a rotating electrical machine (37, M2), the required value for the speed of the variable speed motor (26, M1) being picked up from the conveyor (16) and the actual value from the deflection roller (32), in both directions of rotation, while the machine (37, M2) coupled to the supply spool (33) is operated to yield a braking torque in one direction and a driving torque in the other direction.
2. A device according to Claim 1, characterized in that the variable speed motor (26, M1) is a reversible, frequency-controlled asynchronous machine connected via a feed circuit (42) which is coupled for its part to sensors (40,43) coupled respectively one to the conveyor (16) and one to the deflection roller (32).
3. A device according to Claim 1, characterized in that the variable speed motor (26, M1) is a reversible direct current machine connected via a feed circuit (42) which is coupled to sensors (40,43) coupled respectively one to the conveyor (16) and one to the deflection roller (32).
4. A device according to one of Claims 1 to 3, characterized in that the machine (37, M2) coupled to the supply spool (33) is a direct current servo machine which can be switched to operate as motor and as generator, and which at least when in generator mode is instantaneously torque-controlled according to the momentary value of the diameter of the supply spool.
5. A device according to one of the preceding Claims, characterized in that the deflection roller (32), which is freely rotatable and is made to rotate by the winding strip (34), is arranged between two free-running lead-in belts (30,31) which partially wrap the roll hub (19) or the roll (W) wound thereon as the case may be.
6. A device according to Claim 5, characterized in that the lead-in belts (30,31) run over end rollers (15,29) which are mounted in a frame (28) pushed by spring action against the outer circumference of the roll hub (19) or of the roll (W) wound thereon.
7. A device according to Claim 6, characterized in that the bearings (20,21,22) of the roll hub (19) are guided in a vertically adjustable manner and are coupled to lifting mechanism (24,25) which can be switched on and off, in either direction, according to the position of the frame (28).

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