EP0307603B1 - Wire-rolling mill - Google Patents

Abstract

A wire-rolling mill having a plurality of roughing stands, a cropping shear, a finishing block, a loop layer with a laying pipe and having a drive comprising a loop-layer motor and a loop-layer gearbox and having a discharge conveyor for the finished rolled wire laid out in loops, these parts of the installation being arranged in series in the running direction of the wire. The wire-rolling mill has a control device with a computer, the computer controlling the cropping shear in accordance with a predetermined rolling program by means of a computer cutting command. In accordance with the computer cutting command, the cropping shear cuts off a certain length from the beginning of a wire strand before it enters the finishing block. It thereby produces the head of the wire to be laid out in loops. The cropping length is matched to the position of the loop layer. The loop layer is provided with an angular position sensor, which operates with digital pulses and is connected to the control device and the annular positions of which correspond to the positions of the laying pipe. The control device combines the computer cutting command and digital pulses of a predeterminable laying-pipe position sector by means of an electronic AND circuit to form a position cutting command, the cropping shear thus responding only to the position cutting command. <IMAGE>

Description

The invention relates to a wire rolling mill with a plurality of roughing stands, a cropping shear, a finishing block, a winding layer with a laying pipe and with a drive consisting of a winding layer motor and a winding layer gear, a discharge conveyor for the finished rolled wire laid out in turns, which plant parts are arranged one behind the other in the wire running direction, and with one Control device with a computer which controls the cropping shears according to a predetermined rolling program by means of a cutting command, the winding layer having a rotation angle position transmitter, the angular positions of which correspond to the laying tube positions and which is connected to the control device, the signals of the rotation angle position transmitter with the rolling program for a position cutting command for the cropping shears processed. - The cropping shear is in front of the finishing block. The discharge conveyor usually consists of several parallel pulling devices. It can also be designed as a roller table.

Such wire rolling mills operate at high rolling speeds. The division of a cropping length in front of the finishing block is necessary in such wire rolling mills because the beginnings of the wire strands which leave the roughing mill have irregularities which impair the service life of the rolls or calibres in the finishing block. On the other hand, there is a risk that a wire head that is uncontrolled by the winding layer to the discharge conveyor will not deposit without problems. This can lead to the fact that a complete wire strand cannot be combined into bundles and can be discarded as scrap got to. In order to avoid such faults, an operator stands at the winding layer, who grasps the wire head with a tool and deposits it according to the winding in such a way that the finished rolled wire is fanned out without interference in defined turns.

In a wire rolling mill of the type described at the beginning (FR-A 24 59 085), the measuring devices, in particular the rotary angle position transmitter, and also other setting devices work analogously. The rotary angle position sensor is arranged in the immediate area of the winding layer and is accordingly exposed to considerable heat loads and fluctuating temperatures. In the case of analog measurement technology, the measurement accuracy and accordingly the control of the wire rod mill as a whole can be impaired.

In experiments that are not part of the prior art, the computer takes into account a time span for the computer cut command, which is determined in accordance with the distance between the cropping shear in front of the finishing block and the winding layer, the speed of the wire and the laying tube position and is selected such that the wire head is in a laying tube position sector can hit the discharge conveyor, in which experience shows that the wire head is laid down in accordance with the wind and without problems. To this extent, experience from earlier times (DE-PS 20 38 747) is taken into account, which was obtained in rolling mills with a significantly lower rolling speed, in which the shears could still be arranged behind the finishing block.

Nonetheless, in the tests on the generic rolling mills with their high rolling speed, the described disturbances occurred in statistical distribution in practice. They are based on statistical fluctuations in parameters that the program with which the computer works cannot take into account.

The object of the invention is to improve a wire rolling mill of the type described in the introduction in such a way that system-related malfunctions are excluded.

This object is achieved in that the winding layer has a rotary angle position transmitter working with pulses, which emits 360 equidistant pulses and a defined zero pulse per revolution, that a counter is arranged between the rotary angle position transmitter and an electronic AND logic circuit of the control device, and that the counter with a Preselection is equipped with which the predeterminable laying pipe position sector and the sector width can be set. The counter can be set to a predefined, counting down value after each revolution of the rotary angle position encoder or set to zero when the counting is added. The preselection device should expediently be able to divide each unrotation of the rotation angle position transmitter into a predetermined number of laying tube position sectors, the setting of the sector width of these laying tube position sectors on the preselection device being changeable with increasing wire thickness.

There are several options for further training and design within the scope of the invention. In general, the arrangement will be such that the drive of the winding layer has the rotary angle position sensor. According to a preferred embodiment of the invention, the rotary angle position transmitter is placed on a shaft of the drive with the interposition of an adapter gear, the adapter gear accurately reproducing the positions of the rotary angle position transmitter and the laying tube, including a zero position.

In the case of a wire rolling mill according to the invention, for all wire thicknesses to be controlled, it can be visually determined in which laying tube position sectors the wire head of a new wire strand has to emerge after cutting off a cropping length, so that a winding-like and trouble-free depositing takes place on the discharge conveyor. With this information, the design is such that the control device subjects the computer cut command and the digital impulses of the laying tube position sectors to the AND link and the cropping shear consequently performs the cropping cut at the right moment.

The advantages achieved can be seen in the fact that the disturbances described at the outset and in particular also the statistically distributed disturbances no longer occur in the wire rolling mill according to the invention.

Fig. 1

das Schema eines erfindungsgemäßen Drahtwalzwerkes,

Fig. 2

in gegenüber der Fig. 1 vergrößertem Maßstab Einzelheiten aus dem Drahtwalzwerk der Fig. 1 in bezug auf den Windungsleger und den Drehwinkelpositionsgeber und

Fig. 3

in gegenüber der Fig. 1 vergrößertem Maßstab eine Draufsicht auf den Abführförderer der Fig. 1 mit Bauteilen des Windungslegers.

In the following, the invention will be explained in more detail with reference to a drawing showing only one embodiment. Show it

Fig. 1

the diagram of a wire rolling mill according to the invention,

Fig. 2

in an enlarged scale compared to FIG. 1, details from the wire-rolling mill of FIG. 1 with respect to the winding layer and the rotary angle position transmitter and

Fig. 3

in an enlarged scale compared to FIG. 1, a plan view of the discharge conveyor of FIG. 1 with components of the winding layer.

The wire rolling mill shown is equipped with a plurality of roughing stands 1, a cropping shear 2, compensating device 3, a finishing block 4 with eight stands 5 in the exemplary embodiment, a winding layer 6 with a laying pipe 7, and a drive comprising a winding layer motor 8 and a winding layer transmission 9 and a discharge conveyor 10 for the Finished rolled wire D equipped. Only two last of the roughing stands 1 are drawn. There is a cooling section between prefabricated block 4 and winding layer 6. A driver 11 is connected upstream of the winding layer 6. The wire rolling mill has a control device 12 with a computer 13. The computer 13 controls the cropping shear 2 according to a predetermined rolling program by means of a computer cut command. The cropping shear 2 divides a cropping length from the start of a wire strand before it enters the finishing block 4 in accordance with the computer cut command. This creates the wire head of the wire D to be laid out in turns. The top length is matched in a special way to the position of the laying tube 7. It goes without saying that the cut cropping is discarded and removed, as indicated in Fig. 1 by an arrow behind the cropping shear 2.

As can be seen in FIG. 2, the winding layer 6 has a rotary angle position sensor 14 which works with digital pulses and which is connected to the control device 12. The angular positions of the rotational angle position transmitter 14 correspond to the positions of the laying tube 7. The control device 12 links the computer cut command and the digital pulses of a predefinable laying tube position sector S by means of an electronic AND logic circuit 15 to the position command. The cropping shear 2 only responds to the position cut command.

In the exemplary embodiment and according to a preferred embodiment of the invention, the rotational angle position sensor 14 is integrated with the drive of the winding layer. For this purpose, the rotary angle position sensor 14 is placed on a shaft 17 of the drive with the interposition of an adapter gear 16. The adapter gear corresponds mathematically exactly to the winding laying gear. The arrangement is such that the adapter gear 16 synchronizes the positions of the rotational angle position sensor 14 and the laying tube 7, including a zero position. 360 equidistant pulses and a defined zero pulse may be removable from the rotation angle position transmitter 14 per revolution. Between the rotation angle position sensor 14 and the electronic AND logic circuit 15 there is a counter 18 which resets after each rotation of the rotation angle position sensor 14 and thus of the laying tube 7, the counter 18 being equipped with a preselection device with which the predefinable laying tube position sector S and Sector width B are adjustable.

The preselection device divided each revolution of the rotational angle position sensor 14 and thus of the laying tube 7 into a predetermined number of laying tube position sectors. The sector width B can be changed with the increasing wire thickness.

The laying tube position sectors from which the wire head must exit so that the individual wire strands can be deposited without problems are determined when the wire rolling mill is retracted. Such a laying pipe position sector S is indicated in FIG. 3. The sector width B which can also be seen there is therefore chosen differently in accordance with the wire thicknesses, so that it is always possible to work with a short cropping length. The values once determined are independent of the rolling speed, but change somewhat over time as a result of caliber wear. The corrections required from this can easily be corrected by changing the position of the laying tube position sector in the circulation or increasing the sector width B.

Claims (4)

1. A wire rolling mill with a multiplicity of shaping mills (1), cropping shears (2), a finishing block (4), a coil laying head (6) with a guide tube (7) and with a drive comprising a coil laying head motor (8), a coil laying head transmission (9), a discharge conveyor (10) for the finished rolled wire (D) laid up as coils, which parts of the unit are disposed one behind the other in the direction of travel of the wire, and with a control device (12) with a computer (13) which controls the cropping shears (2) according to a predetermined rolling program by means of a cutting command, wherein the coil laying head (6) has an angular rotation position transmitter (14), the angular positions of which correspond to the guide tube positions, and which is connected to the control device (12) which processes signals from the angular rotation position transmitter (14) by means of the rolling program to give a cutting position command for the cropping shears (2), characterised in that the coil laying head (6) has an angular rotation position transmitter (14) which operates by means of pulses and which emits 360 equidistant pulses and a defined zero pulse per revolution, that a counter (18) is disposed between the angular rotation position transmitter (14) and an electronic AND operation circuit (15) of the control device (12), and that the counter (18) is equipped with a preselector device with which the programmable guide tube position sector (S) and the sector ranges (B) can be set.
2. A wire rolling mill according to Claim 1, characterised in that the drive (8, 9) of the coil laying head (6) has the angular rotation position transmitter (14).
3. A wire rolling mill according to Claim 2, characterised in that the angular rotation position transmitter (14) is placed in series with an adapter transmission (16) on a shaft (17) of the drive (8, 9), and that the adapter transmission (16) reproduces the positions of the angular rotation position transmitter (14) and of the guide tube (7), including a zero position.
4. A wire rolling mill according to Claim 1, characterised in that each revolution of the angular rotation position transmitter (14) can be divided into a predetermined number of guide tube position sectors (S) by the preselector device, and that the adjustment of the sector width (B) of these guide tube position sectors (S) can be altered at the preselector device with increasing wire thickness.

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