At paper, pulp and cardboard mills, the product, which during most of the process is in the form of a roll, is generally moved by rolling. Often the rolling takes place on an inclined surface, utilizing gravity. Along the way there may be a number of stop positions, where operations relating to separation, sorting, storage, quality control, chopping, packaging etc. are performed.

Repeated phases of operation in transfer systems based on rolling are those of pushing the roll to set it moving, control of the rolling mo- tion and gentle reception at the stop position. For these functions, numerous solutions have been developed, some of which are de- scribed in the following patent specifications.

Fl 104367 B describes a solution which can be used both as a push- ing means and as a stopping means. The electric power means is not sensitive to temperature variations and, being provided with sufficient automation, allows individual treatment of rolls of different weights.

FI 920517 and US 531429 disclose more sophisticated pneumatic roll stopping devices. With these devices, gentle stopping can be achieved, but the programs and control systems are complicated.

Further solutions are described in patent specification FI 91315 and in patent application FI 922795.

A comprehensive list of reference specifications relating to control of rolling is given in patent specification FI 96757.

Intermediate stoppers/sorting stoppers are often used in parallel con- figurations comprising up to several tens of stoppers. Therefore, ex- pensive stoppers like those described above are hardly eligible. One solution is described in patent specification FI 97126, in which the adaptation for rolls of different weights is accomplished via adjust- ment of pneumatic pressure. Hydraulic stoppers are also generally used. US company Lamb-Grays Harbor Co. has developed an stop- per based on a hydraulic shock absorber.

The cheapest intermediate stopper solution, i. e. pneumatic flaps without impact absorption, is rough and causes rebounce of the roll.

Known intermediate/sorting stoppers typically recede under the rolling ramp, where it is necessary to provide an appropriate space for the stopper and the required impact absorption systems, where the stop- pers can also be adjusted and serviced.

The roll weights vary from a few hundred kilograms to several tons.

Controlling loads varying within such wide limits by the same stopper is a difficult task. From the above-mentioned patent specifications it can be seen how complicated the solutions required may be.

To keep the kinetic energy of the roll within reasonable limits, the an- gle of inclination of the rolling ramp is minimized. This leads to slow- ness and uncertainty at the start of the motion, and the roll may also stop before the actual stop position. In this case, the operator has to assist manually, which is expensive and hazardous.

From the above comments it is evident that the numerous operations of pushing the rolls to start them moving and especially of arresting them are a significant cost factor. The simplest stoppers cause quality problems. The most sophisticated ones are expensive and their automatic features and/or adjustments are difficult to control.

The method and apparatus of the invention provide an advantageous solution in applications where a roll/roll set is pushed into motion and stopped a plurality of times within a reasonable distance.

The invention is characterized in that a roll/roll set can be set in mo- tion and stopped in a controlled manner at several positions and con- veyed between these. The invention is based on a multi-function ap- paratus, which is preferably provided with the best possible automatic features, i. e. features producing the smoothest acceleration and de- celeration. Even so, the cost per action position remains low.

As the unit controlling the rolling movement takes the roll/roll set at an optimal speed to an stopper array, it is possible to use economi- cally priced sorting stoppers that need not be provided with impact absorption.

No other stoppers receding under the rolling ramp are needed. This is of importance especially when the operations are performed near the floor level. Expensive installations below the floor level can be mini- mized.

The rolling ramp can be implemented with sufficient inclination as the rolls can be controlled by a contact element/contact elements even throughout the rolling process. The transfer takes place securely, fast and still in a gentle manner.

In systems already in use, there often appears a need to make changes in them afterwards. In the case of the system of the inven- tion, many changes can be easily implemented. In many cases it is sufficient to move/add sensors along with a change in software.

In respect of flexibility, the solution can be compared to an industrial robot.

In the following, the invention will be described in detail with reference to the attached drawings.

Fig. 1 presents a partially sectioned side view of an embodiment of the invention fitted in connection with a winder.

Fig. 2 presents an embodiment of a contact element according to the invention in side view.

Fig. 3 presents a second embodiment of a contact element according to the invention in side view.

Fig. 4 presents a third embodiment of contact elements according to the invention in side view.

Fig. 5 presents an embodiment of the invention in top view.

Fig. 1 presents a system according to the invention, applied in con- nection with a ramp to whose upper end a winder pushes a set 1 of rolls slit by it. The roll set 1 rolls along the inclined ramp surface 2, meeting a contact element 3, which has already been set in motion in the same direction and which is part of the apparatus to be described hereinafter. For the sake of simplicity, number 1 is used to refer to both an individual paper/pulp/cardboard roll and a set of such rolls.

The contact element 3 is mounted on a bracket 4, which is connected to carriages 5 via joints 6. The carriages 5 move on bearing wheels 8 along guide beams 7. The operating power for the carriages 5 is ob- tained from a power means 9, preferably a geared motor, engaging a shaft 10.

Mounted on the shaft 10, which is supported with bearings at one end of the guide beams 7, are transmission sprockets 11. Mounted with bearings at the other ends are deflecting pulleys 13. Power transmis- sion is preferably implemented using cogged belts 12, whose ends are secured to the carriages 5 and which pass around the transmis-

sion sprockets 11 and the deflecting pulleys 13. Instead of a cogged belt, it is naturally possible to use a chain, and likewise it is also pos- sible to use a rack and pinion arrangement. As for the power means 9, there are several alternatives from hydraulic motor to electric ser- vomotor. In practice, an electric motor provided with an inverter is the most suitable solution: it is reliable, of economical price and allows sufficiently smooth operation.

The apparatus comprises two carriages 5, two guide beams 7 and two belt drives 11,12, 13, one of each being disposed on either side of the rolling area, preferably above the rolls 1. The structures in question are known in themselves e. g. from gantry robots.

The combination of the carriages 5, the bracket 4 and the contact element 3 forms a unit controlling the rolling motion and is abbrevi- ated as control unit 14.

In a working scheme according to the application, the positions of the contact element 3 at different stages are referred to as P1-P7. The process may be e. g. as follows.

When receiving a roll set 1 at position P1, the control unit 14 recedes in front of the roll set 1 at a speed lower than that of the roll set 1, which therefore meets the control unit 14. The control system adjusts the speed/torque values of the power means 9 so as to ensure that the contact element 3 can not at any stage exert on the roll set 1 a force that would damage the surface layers. When necessary, the control unit 14 decelerates down to a halt and leaves the rolls, e. g. every second roll, to be separated from the set by stoppers in a sort- ing stopper array S (=P2). The control unit 14 stops the other rolls at position P3 at a distance of e. g. half the roll diameter from the previ- ous position.

After the quality control actions have been carried out, the sorting

stopper flaps allow the rolls remaining there to roll on to position P3.

After that, the control unit 14 conveys the rolls to position P4, from where a conveyor C1 transverse to the rolling direction takes the rolls or some of them e. g. to a roll packaging stage.

In a normal situation, the control unit 14 now returns to the beginning of the rolling ramp 2 to receive a new roll set 1. To accelerate the op- eration, the power means 15, e. g. pneumatic cylinders, raise the bracket 4 to a high position. Thus, it will not hit any rolls that may still remain on the conveyor C1 during the return movement.

In the following situations, the control unit 14 will continue conveying the rolls further. Rolls rejected by quality control are conveyed to po- sition P5, from where they are taken to a chopper by conveyor C2.

When the packaging station/stations is/are not in operation, conveyor C1 can not receive any rolls. In this case, it is advantageous to put the rolls in an intermediate storage e. g. by conveying them to the lower end of the ramp, where the power means 15 raise the bracket 4 together with the contact element 3 to position P6. The rolls are thus allowed to roll on, and they will be stored by conventional methods.

The control unit 14 now returns to the upper end of the ramp to posi- tion P7 and the power means 15 lower the bracket 4 together with the contact element 3 to the low position to receive the next roll set 1.

When the rolls are to be returned from the intermediate storage, they are rolled into the working area of the control unit 14, e. g. onto a hori- zontal part L of the ramp. The contact element 3 waiting at position P6 is lowered and the control unit 14 pushes the rolls onto conveyor C1.

Depending on the layout, it may be possible to utilize conveyor C2 as well for intermediate storage. When rolls are returned, the control unit 14 pushes the rolls coming from the intermediate storage from con- veyor C2 onto conveyor C1.

In the embodiment described, it is also possible to form roll sets with a changed order of rolls. To achieve this, rolls are admitted past the sorting stopper array S in a desired order, and the control unit 14 brings them onto conveyor C1, to be conveyed further in the trans- verse direction. If conveyor C1 is a single flat-top conveyor, there are limited possibilities of forming tight roll sets to be packaged. In this case it is possible to utilize conveyor C2 to convey desired rolls in the direction of motion of the conveyor to desired positions, from where they are pushed by the control unit 14 onto conveyor C1.

The invention can be implemented as various different embodiments.

The contact element 3 may consist of rubber or plastic coated rollers 17 as are generally used in roll pushing/receiving devices, the rollers forming a row of a length about equal to that of the roll set 1.

In the embodiment illustrated in Fig. 2, the contact element 3 com- prises a belt 16 passed around rollers 17. Alternatively, several belts 16 are placed side by side. With this solution, a very gentle contact with the paper roll 1 is achieved, which is advantageous in the han- dling of particularly sensitive paper sorts.

The embodiments illustrated in Fig. 3 and 4 are advantageous in the handling of particularly narrow rolls 1 of disc-like shape, which tend to tumble over during the rolling.

It is also possible to move the rolls over recesses below the ramp level, such as the spaces 20 for carriage conveyors and other ob- structions. In these cases it is advantageous to have a contact ele- ment 3 that can engage the roll set 1 from the opposite side, too, in which case the rolling ramp may even be horizontal.

Especially the embodiment presented in Fig. 3 can also be imple- mented as a divided structure comprising several contact units 19

placed side by side. These are provided with separate power means/ motion mechanisms 21, which can be implemented using any of sev- eral known alternatives.

A divided embodiment is especially applicable in cases where it is necessary to change the order of the rolls relative to each other. In this way, it is possible to bring under control only the rolls directly be- low selected contact units 19.

In a solution (not shown) alternative to that presented in Fig. 3, the belt 16 is omitted. In this case, the rollers 17A and 17B form the con- tact element 3.

In the embodiment presented in Fig. 4, one roller 17B has been ar- ranged to be movable relative to the other roller 17A. This provides the possibility that, when roller 17B gives way, roller 17A can receive the roll set 1, whereas during the conveying movement roller 17B is pressed against the roll set 1. The equipment 22 used to raise the contact element 3 is of known construction.

The control unit 14 can also be implemented as a simpler solution in which the bracket 4 is not pivoted on the carriages 5 but is fixedly connected to them (Fig. 5). This is possible in smaller systems where the return movement of the control unit 14 can be delayed until the rolls have been moved away.

In some applications, e. g. after a long rolling movement, the roll set 1 may meet the contact element 3 in an oblique position. As the re- ceiving/damping action occurs over a long distance, this is generally no problem. However, in the case of a long roll set 1, it may be ad- vantageous in extreme cases to adapt the alignment of the contact element 3 with the direction of the outer surface of the roll set 1 when receiving the rolls. This adaptation is achieved by providing each car- riage 5 with a separate power means 9 and power transmission 11,

12,13. The common long shaft 10 is replaced by two short ones. The joints 6 are of a spherical structure. The alignment of the contact ele- ment 3 is adjusted at a suitable point during the operating cycle by a known method, by driving the carriages 5 past calibrating sensors and making the required corrections via the control system.

The control system is preferably built on the basis of a programmable logic.

Other implementations of the invention are also possible. In addition to the winder/packaging environment, the invention can be applied in many other sections in a paper and cardboard factory. In addition, the invention can also be used in the handling of non-woven fabric rolls and equivalent.