GB2184671A - Apparatus for disintegrating paper and cardboard - Google Patents

Abstract

Material to be disintegrated is fed, e.g. from a paper machine, into an open-topped tub (1) from where disintegrated material is removed by means of a pump, and at least two disintegrator units, preferably revolving rotors (3), are positioned on one wall (6) of the tub (1). Hitherto the positioning of the disintegrating devices has been such that they have not provided adequate space therebetween for the pump removing the disintegrated mass, and that the rotors have been arranged in a position non-conductive to efficient utilization of the flow energy, which has resulted in high energy consumption. These drawbacks are now overcome in that straight lines drawn through the axes of the shafts of the rotors (3) intersect at least in one projection. <IMAGE>

Description

SPECIFICATION Apparatus for disintegrating paper and cardboard The present invention concerns apparatus for breaking up paper and cardboard, said apparatus consist ing of an open-topped tub into which material to be disintegrated is fed, e.g. from a paper machine, and from where disintegrated material is removed by means of a pump, and at least two disintegrator units, preferably revolving rotors, positioned on one ofthe tub walls.

This kind of apparatus is used in conjunction with large paper machines to disintegrate the waste paper or cardboard which is produced, e.g. in connection with cutting. The apparatus is placed below the paper machine and provided with trough-like guiding means above itto guidethe material proceeding from the paper machine into the open tub.

The disintegrators, consisting of rotors, are positioned on one of the tub walls. Usually there are two rotors, each provided with its own motor, the rotors being placed side by side at the same height from the bottom of the tub and with their axles parallel to each other. The wall on which the rotors are placed is straight in form, at least as seen from above. The pump for removing the disintegrated mass is usually located outside the tub between the rotor shafts.

Thecurrentconstruction has several drawbacks, one of which is that the disintegrating apparatus used with large paper and cardboard machines is rather too wide, which means that the flow energy cannot be effectively utilized in the disintegration process and a large amount of energy is required in order to achieve good results. Moreover, the space between the rotor shafts is very narrow, so thatthere is not enough room for the pump removing the disintes rated mass. With the increased width of the cur- rently used straight-walled disintegrating apparatus the tub construction becomes costly, because the straight wall requires strong reinforcing structures to support the disintegrator units, since the tub as such is not rigid enough.

The object of the present invention is to provide apparatus for disintegrating paper and cardboard which is free of the drawbacks mentioned above and therefore cheaper to produce, and also has a better form with regard to utilization of flow energy than the corresponding devices known so far.

With this object in view, the apparatus of the invention is characterizell ii that the disintegrator units are so arranged that straight lines drawn through the longitudinal axes intersect in at least one projection.

The most important advantages ofthe invention are the rigidity of the structure and the increased space available for the mass pump between the rotor shafts.

The invention will be described in further detail by reference to an advantageous embodiment, refer encealsobeing made to the accompanying drawings, wherein: Figure lisa schematic view of apparatus for disintegrating paper and cardboard as provided bythe invention, seen in section along the line 1-1 in Figure4; Figure 2 is a view of the apparatus shown in Figure 1, seen from the left; Figure 3 is a plan view of previously known disintegrating apparatus; and Figure 4 is a plan view of the apparatus of the invention, as in Figures 1 and 2.

With reference to Figure 1 apparatusfordisintegrating paper and cardboard as provided by the invention is preferably placed below a large paper machine, so that material to be disintegrated is fed into a tub 1 via its open top. Forthis purpose, inclined guides 2 are provided above the tub 1.

The paper and cardboard are broken up in the tub 1 by means of disintegrator units 3, preferably consisting of rotors. In this embodiment there are two rotors placed at the same height on the same wall 6 ofthe tub 1. Respective motors 4 driving the rotors 3 are locatedoutsidethetub 1 on the same axis.

Figure 2 shows the apparatus of Figure 1 as seen from the left. Between the two rotor and motorshafts there is a pipe5 for removal ofthe disintegrated mass going through thetub wall and connecting two a pump,which,though not shown in the drawing is also preferably placed between the said shafts.

Figure 3 is a plan view of previously known disintegrating apparatus with parallel rotor shafts and a straight rotor mounting tubwall 6. Figure4 is a sim ilarview of the apparatus ofthe invention in which it can be seen that straight lines drawn through the axes of the rotor shafts intersect. Also the rotor mountingtubwall 6 is bent in such mannerthatthe distancetotheoppositewall islargestatthemiddle oftubl.

The invention is not restricted to the examples of its embodiments discussed above, and may be varied within the scope of the following claims.

1. Apparatus for disintegrating paper and cardboard comprising an open-topped tub into which material to be disintegrated is fed and from which disintegrated material is removed by means of a pump, and at least two disintegrator units positioned on one of the walls of the tub, characterised in that the disintegrator units are so arranged that straight lines drawn through their longitudinal axes intersect at least in one projection.

2. Apparatus as claimed in claim 1 wherein the disintegrator units consist of revolving rotors, the imaginary straight lines being drawn through the longitudinal axes of their respective shafts.

3. Apparatus for disintegrating paper and cardboard substantially as hereinbefore described with reference to and as illustrated in Figures 1,2 and 4 of the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (3)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Apparatus for disintegrating paper and cardboard The present invention concerns apparatus for breaking up paper and cardboard, said apparatus consist ing of an open-topped tub into which material to be disintegrated is fed, e.g. from a paper machine, and from where disintegrated material is removed by means of a pump, and at least two disintegrator units, preferably revolving rotors, positioned on one ofthe tub walls. This kind of apparatus is used in conjunction with large paper machines to disintegrate the waste paper or cardboard which is produced, e.g. in connection with cutting. The apparatus is placed below the paper machine and provided with trough-like guiding means above itto guidethe material proceeding from the paper machine into the open tub. The disintegrators, consisting of rotors, are positioned on one of the tub walls. Usually there are two rotors, each provided with its own motor, the rotors being placed side by side at the same height from the bottom of the tub and with their axles parallel to each other. The wall on which the rotors are placed is straight in form, at least as seen from above. The pump for removing the disintegrated mass is usually located outside the tub between the rotor shafts. Thecurrentconstruction has several drawbacks, one of which is that the disintegrating apparatus used with large paper and cardboard machines is rather too wide, which means that the flow energy cannot be effectively utilized in the disintegration process and a large amount of energy is required in order to achieve good results. Moreover, the space between the rotor shafts is very narrow, so thatthere is not enough room for the pump removing the disintes rated mass. With the increased width of the cur- rently used straight-walled disintegrating apparatus the tub construction becomes costly, because the straight wall requires strong reinforcing structures to support the disintegrator units, since the tub as such is not rigid enough. The object of the present invention is to provide apparatus for disintegrating paper and cardboard which is free of the drawbacks mentioned above and therefore cheaper to produce, and also has a better form with regard to utilization of flow energy than the corresponding devices known so far. With this object in view, the apparatus of the invention is characterizell ii that the disintegrator units are so arranged that straight lines drawn through the longitudinal axes intersect in at least one projection. The most important advantages ofthe invention are the rigidity of the structure and the increased space available for the mass pump between the rotor shafts. The invention will be described in further detail by reference to an advantageous embodiment, refer encealsobeing made to the accompanying drawings, wherein: Figure lisa schematic view of apparatus for disintegrating paper and cardboard as provided bythe invention, seen in section along the line 1-1 in Figure4; Figure 2 is a view of the apparatus shown in Figure 1, seen from the left; Figure 3 is a plan view of previously known disintegrating apparatus; and Figure 4 is a plan view of the apparatus of the invention, as in Figures 1 and 2. With reference to Figure 1 apparatusfordisintegrating paper and cardboard as provided by the invention is preferably placed below a large paper machine, so that material to be disintegrated is fed into a tub 1 via its open top. Forthis purpose, inclined guides 2 are provided above the tub 1. The paper and cardboard are broken up in the tub 1 by means of disintegrator units 3, preferably consisting of rotors. In this embodiment there are two rotors placed at the same height on the same wall 6 ofthe tub 1. Respective motors 4 driving the rotors 3 are locatedoutsidethetub 1 on the same axis. Figure 2 shows the apparatus of Figure 1 as seen from the left. Between the two rotor and motorshafts there is a pipe5 for removal ofthe disintegrated mass going through thetub wall and connecting two a pump,which,though not shown in the drawing is also preferably placed between the said shafts. Figure 3 is a plan view of previously known disintegrating apparatus with parallel rotor shafts and a straight rotor mounting tubwall 6. Figure4 is a sim ilarview of the apparatus ofthe invention in which it can be seen that straight lines drawn through the axes of the rotor shafts intersect. Also the rotor mountingtubwall 6 is bent in such mannerthatthe distancetotheoppositewall islargestatthemiddle oftubl. The invention is not restricted to the examples of its embodiments discussed above, and may be varied within the scope of the following claims. CLAIMS

1. Apparatus for disintegrating paper and cardboard comprising an open-topped tub into which material to be disintegrated is fed and from which disintegrated material is removed by means of a pump, and at least two disintegrator units positioned on one of the walls of the tub, characterised in that the disintegrator units are so arranged that straight lines drawn through their longitudinal axes intersect at least in one projection.

2. Apparatus as claimed in claim 1 wherein the disintegrator units consist of revolving rotors, the imaginary straight lines being drawn through the longitudinal axes of their respective shafts.

3. Apparatus for disintegrating paper and cardboard substantially as hereinbefore described with reference to and as illustrated in Figures 1,2 and 4 of the accompanying drawings.