US3709441A

US3709441A - Machine for disintegration of cellulose pulp sheets

Info

Publication number: US3709441A
Application number: US00118460A
Authority: US
Inventors: H Hessner; P Nilsson
Original assignee: Stille Werner AB
Current assignee: Stille Werner AB
Priority date: 1970-02-24
Filing date: 1971-02-24
Publication date: 1973-01-09
Anticipated expiration: 1990-01-09
Also published as: DE2108744A1; SE334811B; GB1302985A; CH513286A; FR2083123A5; SU413685A3

Abstract

A machine for disintegration of cellulose pulp sheet which comprises an essentially vertical magazine to receive pulp sheet bales with the sheets preferably lying horizontally, said magazine having a bottom consisting of a bed of slightly spaced, mutually parallel tearing tooth rods which are longitudinally relatively movable to one another and may include two groups which are alternately movable in opposite directions.

Description

United States Patent 1 Hessner et al.

MACHINE FOR DISINTEGRATION OF CELLULOSE PULP SHEETS Inventors: Hans Hessner, Djursholm; Per Olof Nilsson, l-lallsberg, both of Sweden Assignee: Aktiebolaget Stille-Werner,

Stockholm, Sweden Filed: Feb. 24, 1971 App1.No.: 118,460

Foreign Application Priority Data Feb. 24, 1970 Sweden ..2362/70 [1.8. CL ..24l/94, 241/263 Int. Cl .l ..B02 1/12 Field of Search ..24l/28, 94, 262, 263,283; 144/189; 146/149, 150 R 1451 Jan. 9, 1973 [56] References Cited UNITED STATES PATENTS 2,342,213 2/1944 Ostrander .241 /94 208,890 10/1878 Cornell et a1... .241/28 868,617 10/1907 Scozzari ..241/283 x 3,502,275 3/1970 Watson .241 94 x Primary Examiner-Granville Y. Custer, Jr. Attorney-Martin Kirkpatrick [57] ABSTRACT A machine for disintegration of cellulose pulp sheet which comprises an essentially vertical magazine to receive pulp sheet bales with the sheets preferably lying horizontally, said magazine having a bottom consisting of a bed of slightly spaced, mutually parallel tearing tooth rods which are longitudinally relatively movable to one another and may include two groups which are alternately movable in opposite directions.

8 Claims, 2 Drawing Figures PATENTEUJAN 9 I973 3 709' SHEET 1 UF 2 PATENTEDJAN 9|975 3 709441 SHEET 2 BF 2 MACHINE FOR DISINTEGRATION OF CELLULOSE PULP SHEETS For disintegration of cellulose pulp in sheets which are normally delivered from the mills in big bales one has heretofore as far as known essentially relied upon a softening of the normally very hard pulp sheets in water in connection with the disintegration. This has not caused any problems because one has in any case been working with the pulp in a water suspension of a rather low concentration in the succeeding steps of the process in question, such as at paper making. However, with the increased use of cellulose as fluff, i.e., a dry defibrated pulp wherein the fibers are comparatively well separated from each other, it has been necessary to develop disintegrating or defibrating means of a sufficient capacity and reliability; at the same time it has been found necessary to ensure that the disintegration or defibration is not carried on too far, so that a great proportion of the pulp is converted into something which might be termed short staple cellulose dust.

One known device for the disintegration of cellulose pulp is the so called hammer mill which, however, has the inherent disadvantage as far as the raw material is concerned that it is limited to work with pulp webs on rolls. However, as cellulose pulp is commonly delivered in sheets, packed in bales, attempts have been made to come to a disintegration or dry defibration directly from the bales. One such proposal involves the use of a plurality of parallel saw or tearing tooth chains which act on the bales from one side. The results heretofore achieved are not satisfying from the quality point of view, and furthermore it has been found that the power demand is too high; also, such proposed machines with saw or tearing tooth chains are comparatively susceptible to operational disturbances.

The object of the present invention is to provide a machine for the disintegration of cellulose pulp sheets wherein the above discussed limitations and drawbacks are eliminated. To this end, apparatus according to the invention comprises an essentially vertical magazine to receivepulp sheet bales with the sheets preferably lying horizontally, said magazine having a bottom consisting of a bed of slightly spaced, mutually parallel tearing tooth rods which are longitudinally relatively movable to one another and may include two groups which are alternately movable in opposite directions.

The invention will be disclosed in more detail below with reference had to the accompanying drawings, wherein:

FIG. 1 is a perspective view, partly in section, of apparatus according to the present invention;

FIG. 2 is a perspective view of a complete disintegrating machinery, including the apparatus of FIG. 1.

The apparatus of FIG. 1 comprises a frame which supports an at least essentially vertical magazine 11 which may be open on one side to permit inspection of the supply of pulp sheets therein. At least the upper part of the magazine has two flaps 13,14 which may be swung sidewardly by means of hydraulic or pneumatic cylinders 12 to permit loading of cellulose pulp sheet bales from one side, e.g. by means of a fork lift truck. The pile of pulp sheets has been denoted 15.

The bottom of the magazine on which the pile of pulp sheet rests, comprises a bed of slightly spaced tearing tooth bars 16. In the example shown, the bars 16 are divided into two groups, with the bars of each group disposed alternately with the bars of the other group and with the bars 16 of both groups longitudinally movable to-and-fro, alternately in opposite directions. The movement is in this case accomplished by means of a crank and lever mechanism, generally denoted 17, which over a suitable transmission 18 is driven by means of an electric motor 19. In as much as a plurality of different drive mechanisms may be used to drive the toothed rods 16 to-and-fro through a suitable stroke which may be variable, if desired, and with a suitable frequency, it has been deemed unnecessary to disclose such mechanisms in more details. The rods 16 of each group are preferably rigidly interconnected and the respective groups are guided on guide rails 20 over rollers 21,22. At each end of the magazine there are provided stripping plates 23,24 which have teeth or protrusions extending down between the rods 16. Such plates with protrusions prevent the pulp from passing out laterally for which reason the pulp falls down a hopper 25 or the like to a conveyor (not shown in FIG. 1) or directly to a mill or the like for a continued disintegration.

The design of the teeth of the rods 16 and the mutual spacing between such rods as well as the stroke and frequency thereof may be varied as necessary. For certain applications, it would also be possible to arrange only some of the rods movable whereas the others may be arranged stationary.

It should be mentioned that the pulp sheets are not drydefibrated entirely in the machine in FIG. 1 so it may be used directly as fluff in diapers or similar absorbant pads, for example, moreover, the machine in FIG. 1 should preferably be followed by some other machine, such as a hammer mill, for instance, which brings about the final dry defibration. However, it has been found that such a subsequent machine will have such a great capacity and gives a product of such a high quality that the use of a machine as shown in FIG. 1 in a precedent step is more than well justified. i

The probably most surprising fact with the machine according to the invention is that the capacity thereof and the outer appearance of the pulp pieces torn off from the sheets are remarkably uninfluenced by the height of the sheet pile 15 in the magazine. Of course, this fact is very important for the function of the subsequent machine or mill so that this machine may give off an entirely uniform product, irrespective of whether or not the preceding machine according to the invention works with a full or nearly emptied magazine.

FIG. 2 shows a machine for drydefibration of cellulose pulp to be used as fluff" or absorbent filler in diapers, sanitary pads and the like. This machinery comprises a disintegrator, generally denoted 50, which is preferably of the kind as shown in FIG. 1. The pulp sheet pieces are fed down on to a conveyor 51, driven by a drive mechanism 52. The conveyor 51 brings the pulp sheet pieces upwardly to the upper end of a mill 53, from which the still further disintegrated pulp sheet pieces are brought upwardly by means of a second conveyor 54, and areplaced on a further overhead conveyor 55 which may run horizontally beneath the ceiling of a diaper plant, for instance.

A guide 56 diverts the pieces off from the overhead conveyor 55 into a hopper 57; preferably the plant has one such hopper 57 for each manufacturing line in the plant, in which case the guide 56 may take only a part of the mass off from the overhead conveyor 55 for each hopper.

The hopper 57 stores a supply 58 of disintegrated pulp which may be ready for use or nearly ready for use. The bottom of the hopper is constituted by the upper flight of an endless belt 59, driven in the direction indicated by arrow A, and one side wall of the hopper is constituted by the inner flight of another endless belt 60, driven in the direction as indicated by arrows B. These conveyors or belts 59 and 60, which have serrated surfaces or surfaces with protrusions, ridges or the like, serve to bring about a mixing action in the pulp supply 58 to make it uniform in consistency. A brush roller 61 serves to take out the disintegrated pulp from a slot between belts 59 and 60.

What we claim is:

l. A machine for disintegration and drydefibration of cellulose pulp sheets, comprising an essentially vertical magazine to receive pulp sheet bales with the sheets lying horizontally, said magazine having a bottom consisting of a bed of slightly spaced, mutually parallel tearing tooth rods, of which at least some are longitudinally movable to-and-fro, said tearing tooth rods being divided into two groups which are alternately movable in opposite directions.

2. A machine as claimed in claim 1, wherein the tearing tooth rods of each group are mutually interconnected and in that the two groups are alternately movable to-and-fro in opposite directions.

3. A machine as claimed in claim 2, wherein the two groups of tearing tooth rods are movable to-and-fro by means of the same drive mechanism.

4. A machine as claimed in claim 1, further including stripper plates disposed transversely of said rods at the ends of the tearing tooth rod bed.

5. A machine as claimed in claim 3 wherein said drive mechanism includes a crank and lever means having adjustable stroke and frequency.

6. A machine for disintegration and drydefibration of cellulose pulp sheets, comprising an essentially vertical magazine to receive pulp sheet bales, said magazine having a bottom consisting of a bed of slightly spaced, mutually parallel tearing tooth rods longitudinally relatively movable to one another.

7. A machine as claimed in claim 6, wherein the tearing tooth rods are divided alternately into two groups.

8. A machine as claimed in claim 7 further including stripper plates having protrusions extending down between the tearing tooth rods disposed transversely of said rods at the ends of the tearing tooth rod bed.

Claims

1. A machine for disintegration and drydefibration of cellulose pulp sheets, comprising an essentially vertical magazine to receive pulp sheet bales with the sheets lying horizontally, said magazine having a bottom consisting of a bed of slightly spaced, mutually parallel tearing tooth rods, of which at least some are longitudinally movable to-and-fro, said tearing tooth rods being divided into two groups which are alternately movable in opposite directions.