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

The invention also relates to a reel-up according to the preamble of claim 6.

As known in the state of the art, when full-width web reels i. e. machine reels are wound, a new, empty reel spool is brought from the reel spool storage and connected to the drive of the primary reeling device, i. e. the primary drive, after which the speed of the empty reel spool is accelerated to web speed. The reel that is being finished and which is connected to the drive of the secondary reeling device, i. e. the secondary drive, is transferred on a reeling carriage to a secondary braking position. The web is transferred by means of blows or equivalent to run onto the new reel spool. The web is cut off and the finished machine reel is braked in the secondary braking position and a new reel is started to be reeled on the primary reeling device. After that, the reeling carriage is moved to the primary reeling device to receive the reel before the maximum diameter of the primary reeling device has been reached.

The recent development of technology has led to the fact that the braking in the secondary position takes longer than previously because larger machine reels are made, which means that inertia is higher. In addition, machine speeds are increasing, so that braking starts from a higher speed, which further causes the braking time to be lengthened. Thus, it is becoming a problem that the new reel reeled on the primary reeling device reaches its maximum diameter before the reeling carriage manages to return from the secondary position to fetch the reel, i. e. before it is possible for the reel to be delivered to the reeling carriage.

The speeding up of braking is problematic because of the mechanical limitations imposed by the devices used, for example, motors, gearboxes and other equivalent devices. In particular, limitations are caused here by the fact that the drives must be movable and the frame structures used in connection with them impose further mechanical limitations.

The problem described above might also be solved by increasing the diameter of the primary reel, but it would lead to expensive, heavy and space-consuming arrangements.

In other words, the problem underlying the invention is that at high reel diameter growth speeds, in particular when using high running speeds and a web of great thickness, the reeling carriage does not have time to come from the change position, i. e. from the discharge position of the finished reel to the changeover of load/drive before the maximum diameter of the primary reeling is reached. Thus, the problem is encountered in particular in centre drive reel-ups that are provided with a secondary reeling carriage and in which the finished machine reel is slowed down by means of the centre drive in a controlled manner.

A further problem underlying the invention is that the alternative solution concerning the increasing of the maximum diameter of the primary reeling device is not efficient because in the future, with the further development of technology, for example, with increasing running speeds, it will be necessary to further increase the diameter of the reel formed on the reel spool and the diameter of the reel spool.

An object of the invention is to provide a solution to eliminate or at least minimize the problems described above.

With a view to achieving the objects described above as well as those coming out later, the method according to the invention is mainly characterized by what is stated in the characterizing part of claim 1.

The reel-up according to the invention is in turn mainly characterized by what is stated in the characterizing part of claim 6.

In accordance with the invention, a separate braking device, which can be, for example, an electric motor and/or a mechanical brake, is placed in the braking position of the secondary carriage. After a changeover has taken place from a full finished reel/reel that is being finished onto a new reel spool, the braking device is connected to the full finished reel/reel that is being finished, so that the secondary centre drive can be disengaged and there is time for the secondary carriage to be moved in order to fetch the reel before the maximum diameter of the primary reeling device is reached.

In the arrangement in accordance with the invention, controlled braking of the machine reel finished on the secondary centre drive reel-up is performed both by means of the secondary drive and by means of a separate braking device.

The arrangement in accordance with the invention makes it possible to perform reeling as a continuous operation and the slowing down of production caused by the interruption of the sequence is eliminated. In addition, the arrangement in accordance with the invention is inexpensive because larger devices and structures need not be used although the size of the machine reel and speeds increase.

The invention allows larger machine reels to be wound and speed to be increased.

The invention also makes it possible to lengthen the braking time, whereby the stresses the reel is subjected to during braking can be minimized. In accordance with one advantageous additional feature of the invention, the braking position of the braking device is movable, so that it can move in order to receive and to

transfer the reel aside for the purpose of braking. In that connection, the braking device, which moves substantially in the same direction as the reeling carriage, can move in a position parallel with the reeling carriage, part of the movement length for transferring the reel spool from the reeling carriage to the braking position of the braking device is overlapping.

It is advantageous to control the moment of the braking device used in the reel-up and in the method in accordance with the invention in the same manner as the moment of the secondary centre drive is controlled such that the moment is constant for the time of braking and increasing towards the end of braking. In connection with the invention it is possible to apply a procedure known in itself, such as is disclosed in FI patent application FI 982248, in which during braking a pressing device, for example, a pressing roll is used as an aid of the secondary centre drive to distribute the braking moments. The pressing device is attached to the secondary carriage and it is under load when braking is started by means of the secondary drive but moves away when braking continues in the braking position. Water or an adhesive depending on the paper grade is then sprayed under the surface sheets of the reel before the pressing device is removed. When the speed has slowed down, the water/adhesive prevents the surface from being unwound.

When needed, the surface of the finished machine reel is pressed with the pressing device, for example, a pressing roll, a brush, a spreader bar or an air pressing device, in a separate position even though the secondary carriage would have already moved in order to fetch a new reel that is being finished if the unwinding of the surface has not been prevented by other means, for example, utilizing an adhesive or water.

In the following, the invention will be described in greater detail with reference to the figures in the appended drawing, but the invention is by no means meant to be narrowly limited to the details of them.

Figures 1A-1D are schematic views of one prior art arrangement in connection with the changeover process in a reel-up.

Figures 2A-2D are schematic views of one application of the invention in connection with the changeover process in a reel-up.

Figures 3A-3D are schematic views of another prior art arrangement in connection with the changeover process in a reel-up.

Figures 4A-4D are schematic views of another application of the invention in connection with the changeover process in a reel-up.

In the following Figs. 1A-2D, the same reference numerals are used of the parts corresponding to one another. The reference numerals of the prior art arrangement are provided with apostrophes and when the arrangement in accordance with the invention is described, the same reference numerals without apostrophes are used of the corresponding parts. The reference arrows shown in the figures to indicate directions are denoted with the letter S and a subscript indicates which part is referred to and further, as also otherwise, the reference signs relating to the prior art are shown with apostrophes and those without an apostrophe relate to an arrangement in accordance with the invention.

As shown in Fig. 1A, as known in the prior art, in the stage before a changeover as shown in the figure, a web W'is wound into a reel 12'being formed on a reel spool 17'of a secondary reeling device. The reel spool 17'is connected to a secondary drive 13'and placed in a reeling carriage, i. e. in a secondary carriage 14'. A surface holding device, i. e. a pressing device, for example, a pressing roll 19'defines a reeling. nip with the reel 12'that is being finished and rotates as shown by the arrow S'ls. The pressing roll 19'also prevents access of air into the reel 12'. A new reel spool 15'connected to a primary drive 16'of a reeling

carriage (not shown) of a primary reeling device has been brought to the vicinity of a reel drum 10'to change reeling to a primary position. The reel spool 15'has been accelerated to reeling speed. The reel drum 10'rotates in the direction indicated by the arrow S'lo and, correspondingly, the reel spool 15'rotates in the direction indicated by the arrow S'15. The direction of rotation of the full reel that is being finished is indicated by the reference arrow S'l2. The reel drum 10'is provided with a drive 18'.

In the changeover process shown in Fig. 1B, in the arrangement of the prior art, the web W'has been cut off and the web W'to be reeled is guided to run around the new reel spool 15', for example, by means of blows or equivalent (not shown).

The reel spool 15'has been brought into nip contact with the reel drum 10'to form a reeling nip. The web tail W'of the full finished reel 12'in a secondary reeling position is held against the surface of the reel using a pressing device, for example, the pressing roll 19'.

In the stage shown in Fig. 1C, the finished reel 12'is braked in the secondary position, and in the primary reeling position the web W'is wound around the reel spool 15'by means of a reeling nip between the reel drum 10'and a web reel 20' that is building up. The pressing roll 19'still ensures that the tail of the web W' remains in contact with the reel.

Fig. ID shows the problem with today's technique, i. e. that the maximum diameter of the web reel 20'being reeled in the primary position is reached before the reeling carriage 14'manages to fetch the reel 20'and before the reel 20'can be delivered to the reeling carriage. The reeling carriage 14', the secondary drive 13' and the pressing roll 19'are just moving in order to fetch the reel 20'from the primary reeling position. The finished reel 12'in the secondary reeling position has been stopped and it is transferred for further processing.

Fig. 2A shows the situation before a changeover when an arrangement in accordance with the invention is applied. A web W is wound into a reel 12 around a reel spool 17 in a secondary position. A secondary drive is denoted with the reference numeral 13 and a reeling carriage is denoted with the reference numeral 14. A pressing device, for example, a pressing roll 19 is used for forming a reeling nip and also for preventing access of air into the reel 12 that is being finished. A new reel spool 15 has been transferred to the vicinity of a reel drum 10 provided with a drive 18 and a primary drive is denoted with the reference numeral 16. In this arrangement, a braking device 23 has been arranged in connection with the secondary drive 13.

In the changeover process stage shown in Fig. 2B, reeling is changed over from the secondary reeling device to the primary reeling device and the web has been cut off and the tail of the web is guided to run around the new reel spool 15 by means of blows or equivalent, which reel spool has been moved into nip contact with the reel drum 10 to start reeling on the primary reeling device. The secondary reel is braked in the secondary position by. means of the secondary drive 13 and the braking device 23 and, when needed, the tail of the web W is held against the surface of the reel using a pressing device, for example, the pressing roll 19. The pressing roll 19 can also be used as an aid in distributing the braking moments.

As shown in Fig. 2C, the finished machine reel 12 is braked in a separate braking position and braking is accomplished by means of the braking device 23, in which it is possible to use an electric motor, a mechanical brake, a hydraulic motor, a gearbox, a belt transmission or a combination of them. In that connection, the reeling carriage 14 and the secondary drive become free and the reeling carriage 14 starts to move towards the primary reeling position. The pressing roll 19 still ensures that the tail of the web W remains in contact with the reel 12.

As shown in Fig. 2D, the reeling carriage 14 has time to fetch the reel 20 and there is time for the reel to be delivered to the reeling carriage 14 before the

maximum diameter of the primary reeling device is reached, after which reeling is carried on by means of the secondary reeling device. The finished reel 12 is stopped by means of the braking device 23, after which it is transferred for further processing. The pressing roll 19 is moved Sls towards the secondary reeling position and moved into connection with the reel 20, when needed.

In the following Figs. 3A-4D, the same reference numerals are used of the parts corresponding to one another. The reference numerals of the prior art arrangement are provided with apostrophes and when the arrangement in accordance with the invention is described, the same reference numerals without apostrophes are used of the corresponding parts. The reference arrows shown in the figures to indicate directions are denoted with the letter S and a subscript indicates which part is referred to and further, as also otherwise, the reference signs relating to the prior art are shown with apostrophes and those without an apostrophe relate. to an arrangement in accordance with the invention.

Figs. 3A-3D show an arrangement known in the prior art in a reeling device in which the changeover is made while the reeling nip is closed Fig. 3A shows the situation before the changeover. The reference numeral 30' designates a reel drum rotating as shown by the arrow S'30, and the drive of the reel drum 30'is denoted with the reference numeral 38'. A web is wound around a reel spool 37'and the reel spool 37'is provided with a drive 33'. The reel that is being finished is denoted with the reference numeral 32'and a reeling carriage 34' is in connection with the reel spool 37', and the direction of rotation of the reel being finished is denoted with the reference arrow S'32. A pressing device, for example, a pressing roll 39'is in its ready position and rotates as shown by the arrow S'39.

Fig. 3B shows the changeover process. The web has been cut off and one end of the web W'is held against the surface of a reel 32'being finished by means of a

pressing device, for example, the pressing roll 39', which rotates as shown by the arrow S'39 and it has been moved upwards to form a nip with the reel that is being finished, which is indicated by the arrow S'y. A new reel spool 35'rotating as shown by the arrow S'35 is provided with a primary drive 36'and the other end of the web W'has been transferred into connection with the reel drum 30'. The surface holding device, i. e. the pressing roll 39'has been engaged immediately after the changeover.

In the situation shown in Fig. 3C, the finished reel 32'is transferred on the reeling carriage 34'to a secondary position and it is braked using the secondary drive 33'.

A reel 40'to be wound around the reel spool 3S'by means of the reel drum 30'is transferred to a reeling position, whereat the primary reeling device is turned down onto reeling rails and the diameter of the primary reel increases. The end of the web is still held against the finished reel 32'by means of the pressing device 39'.

Fig. 3D shows the problem of the arrangement known from the prior art, i. e. the reel 40'reeled on the primary reeling device in the primary position reaches the maximum diameter before the reeling carriage 34'manages to fetch the reel/the reel 40'can be delivered to the reeling carriage 34. The pressing device, for example, the pressing roll 39'moves with the. reeling carriage as shown by the arrow S'39.

Figs. 4A-4D show the changeover process in an arrangement in accordance with the invention, in which the changeover process is carried out while the nip is closed.

Fig. 4A shows a situation in which a web has been just cut off and the situation corresponds to the stage shown in Fig. 3B in the prior art. A braking device 43 used as an aid in the arrangement in accordance with the invention is in a ready position. The reeling of the web into a reel 32 in a secondary position has ended

and one end of the web W is held against the surface of the reel using a pressing device 39. The reel 32 being finished is braked by means of a secondary drive 33.

The other end of the web has been transferred to run around a new reel spool 35 brought into connection with a reel drum 30. In the primary reeling device, the primary drive is denoted with the reference numeral 36 and the drive of the reel drum is denoted with the reference numeral 38.

Fig. 4B shows a situation in which the secondary reeling device is transferred to a braking position and the braking device 43 has been brought into connection with the secondary reeling device and the reel is braked. The pressing device 39 can be used as an aid in distributing the braking moments. In the primary reeling position, the primary reeling device is turned down onto reeling rails or equivalent and the diameter of the reel starts to increase around the reel spool 35. The new reel that is building up is denoted with the reference numeral 40.

In the stage shown in Fig. 4C, the secondary reeling device is disengaged from the finished reel 32 and braking is carried on only by means of the braking device 43.

The pressing roll 39 is still used for holding the web against the surface of the reel. A reeling carriage 34 and the secondary drive 33 move towards the primary reeling position, in which the reel 40 that is building up is reaching its maximum - diameter : The braking of'the finished reel 32 is accomplished in this braking position by means of the braking device 43, for example, an electric motor, a mechanical brake or a combination of them. In that connection, the reeling carriage 34 becomes free to move S34 towards the primary reeling position already during the braking of the finished reel 32. The surface holding device, for example, the pressing roll 39 remains in the braking position for the entire time of braking.

In the situation shown in Fig. 4D, reeling has changed over to the secondary reeling device because the reeling carriage 34 has had time to fetch the new reel 40/there has been time for the new reel 40 to be delivered to the reeling carriage

34 before the maximum diameter of the primary reeling device is reached. The pressing roll 39 is moved to the primary reeling position after braking has ended in the secondary reeling position. The finished reel 32 is transferred for further processing.

Above, the invention has been described only with reference to some of its advantageous application examples, but the invention is not by any means meant to be narrowly limited to the details of them.