FI72356C - Device for destruction of paper and cardboard. - Google Patents

Description

72356

PAPER AND BOARD LIMITING DEVICE - ANORDNING FÖR DESTRUKTERING AV PAPPER OCH KARTONG

The present invention relates to an apparatus for disintegrating paper and board, comprising an open-top bath into which the raw material to be disintegrated is fed, for example from an overhead paper machine and discharged by a pump, and at least two diffuser units located on one wall of the bath, most preferably rotating rotor.

A device like this is used under large paper machines to break up excess paper and board, for example generated as cutting waste. Above the device, trough-like guide members are formed which guide the paper to be disintegrated from the paper machine and the paperboard into an open bath at its upper end. Diffuser units, on which the rotors act, are placed on one wall of the bath. Most often there are two rotors and each has its own drive motor. The rotors are currently placed side by side at the same height from the bottom of the tub and their axes are also parallel. In this case, the wall of the bath in which the rotors are placed is straight, at least when viewed from above. Outside the bath, a scattered mass discharge pump is usually placed between the rotor shafts.

However, the current technology has several drawbacks, one of which is that under wide paper and board machines, the diffusers are wide, so that the utilization of the flow in the paper or board disintegration is not efficient enough, but requires a lot of energy to achieve a good disintegration result. In addition, the space between the drive shafts of the diffuser rotors is very small, leaving little space for the dissipated pulp discharge pump. As the width of existing straight-wall diffusers increases, the tub construction becomes expensive because rotors placed on a straight wall require a lot of support structures, as the tub as such is not rigid 72356 2.

The object of the present invention is to provide an apparatus for breaking up paper and board, which apparatus does not have the above-mentioned drawbacks and which is thus more advantageous to manufacture and flow-shaped better than the currently known devices. The device according to the invention is characterized in that the lines passing through the axis lines of the rotors intersect at least in one projection.

The main advantages of the device according to the invention are the rigidity of the structure and the additional space obtained for the pulp pump between the axes.

In the following, the invention will be explained in detail, by means of an example of a preferred embodiment, with reference to the accompanying drawing, in which

Fig. 1 is a side view, sectioned along the line I-I in Fig. 4, of an apparatus according to the invention for shredding paper and board.

Figure 2 shows Figures 1 seen from the left.

Fig. 3 shows a known device from above.

Fig. 4 shows a top view of a device according to the invention.

Figure 1 shows an apparatus according to the invention for breaking up paper and board. The device is most preferably located below a large paper machine, whereby the substance to be disintegrated is fed to the bath 1 via the open top of the bath. Oblique 3 72356 guides 2 are formed above the bath for this purpose.

The disintegration of the paper and board in the bath 1 takes place by diffuser units 3, which are most preferably rotary rotors. In this exemplary embodiment, there are two rotors and they are located at the same height and on the same wall of the tub 1. The drive motors 4 of the rotors 3 are arranged coaxially with the rotors outside the tub.

Fig. 2 shows the device according to Fig. 1 seen from the left. It can be seen that between the shafts between the drive motors and the rotors is connected to the wall of the bath a disintegrated pulp discharge pipe 5. This is connected to a pulp discharge pump, not shown in the figures, but also most preferably located between said shafts.

Figure 3 shows a top view of a known diffuser device. In it, the axes of the rotors 3 are parallel. In this case, the wall 6 of the bath 1 is also straight. Figure 4, on the other hand, shows a top view of a device according to the invention. As can be seen, the extensions of the rotors 3 intersect. The wall 6 is bent so that the widest point of the tub 1 is in the middle thereof.

It will be clear to a person skilled in the art that the invention is not limited to the above-mentioned exemplary embodiments, but can be varied within the scope of the appended claim.

Claims (1)

72356 A claim (6) a diffuser unit (3), most preferably a rotating rotor, characterized in that the lines passing through the axial lines of the rotors (3) intersect at least in one projection. Il