WO1990015185A1

WO1990015185A1 - A device for removing waste paper that falls under a paper machine

Info

Publication number: WO1990015185A1
Application number: PCT/FI1990/000146
Authority: WO
Inventors: Arvo Kartano
Original assignee: Jymet Oy
Priority date: 1989-05-31
Filing date: 1990-05-30
Publication date: 1990-12-13
Also published as: FI82504B; FI82504C; FI892631A0; AU5663490A

Abstract

The object of the invention is a device for removing the waste paper or similar that falls beneath a paper machine, which device consists of an endless, continually circulating conveyor screen (3). In accordance with the invention the first section (1) of the upper section of travel (4) is essentially arranged horizontally, and the necessary rising final section (2) is formed between the first and second rollers (6, 7), and that the device includes a third roller (9) located essentially further than the aforementioned first roller (6), which with the first roller (6) creates a backwards directed loop in the upper section of travel (4), and in which the waste paper in arranged to drop from the third roller (9) onto the rising final section (2).

Description

A Device for removing Waste Paper that falls under a Paper Machine

The object of the invention is a device for removing waste paper or similar matter that falls under a paper machine, which device consists of an endless, continually rotating conveyor screen, and which screen permits drying air to blow through it, and in which the endless conveyor screen extends essentially for the entire length of the drying section of the paper machine, and the discharge end of which is located on top of the edge of a pulper or similar that is essentially above the level of the floor.

A considerable amount of waste paper collects underneath the drying section of a paper machine in connection with breaks in the paper web. At present, various kinds of conveyor devices are used to remove the waste paper. Often conveyors in sequence are used, each of which is equipped with its own rotation devices and tensioning devices, which makes the system complicated and expensive. On the other hand, it is often impossible to get one conveyor to fit under the paper machine, because the structure of the drying section extend low down and also the edge of the pulper rises considerably above the level of the floor.

Finnish Publication Print 57287 also presents one solution for removing waste paper from beneath a paper machine. In this solution a large gatherable cloth is used, which is spread beneath the paper web to collect the waste paper, and which is then wound round an operating roller, when the waste paper is made to travel towards the operating roller, and from which it can be dropped into the pulper or other reservoir. After this the cloth is rolled open again, when it is ready to receive a new batch of waste paper.

As the size of paper machines increases, the conveyor device must now be constructed over a length of 70 - 100 metres, which causes new construction difficulties to control such a long track. The intention of this invention is to create a waste paper conveyor device that is simpler than the above, and which can easily be installed even under an old paper machine. The charac¬ teristic features of the device in accordance with the invention appear in the accompanying Patent Claim 1. Other advantageous forms of application of the invention appear in connection with the accompanying example of application. In what follows, the invention is illustrated with reference to the accompanying figures, which show one form of application of the invention.

Figure 1 shows the device for removing waste paper Figure 2 shows the device in Figure 1, seen from above Figure 3 shows a partial enlargement of Figure 1.

The waste paper conveyor is constructed inside the hood 17 in the basement level, whereas the cylinders of the drying section itself are principally located above the base level. Figures 1 and 2 show a device in accordance with the invention in connec¬ tion with a real paper machine. Various machines differ from one another to some extent, but there are certain common features. Normally the edge of the pulper is quite high up, and some of the screens of the drying section extend so far down that it is not possible to construct a straight single stage conveyor.

The conveyor screen 3 consists of a horizontal first section 1 and a rising second section 2 , which is formed between the first roller 6 and the second roller 7. The direction of travel of the conveyor screen 3 is then selected in such a way that the upper part of its travel 4 conveys the waste paper from the beginning to the pulper 8. Many screens of the drying section, however, come very low down, for which reason there is very little height available. Figure 1. The first section 1 of the conveyor screen can advantageously always be arranged horizontally, in which case it is simple to construct. The second section 2 is, on the contrary, arranged at a sufficient angle to create the necessary height at the discharge end 16, when the conveyor screen extends sufficiently to drop the waste paper into the pulper 8. The entire conveyor screen 3 is constructed between the front end roller 10 and the second roller 7 of the discharge end 16. Auxilliary roller 13, 14 are used both above and beneath.

5 The first section is turned upwards by means of the aforemen¬ tioned first roller 6 and the third roller 9, Figure 3. Here, the first roller 6 is taken behind the third roller 9, in which case the upper part of the conveyor travel 4 of the conveyor 3 creates a rearwards oriented loop, when the waste paper is made 10 to fall from the third roller 9 onto the rising section 2. By means of these two rollers 6 and 9, as well as the second roller 7 the angle of the rising section 2 can be adjusted as desired.

The detaching of the waste paper from the third roller can be 15 improved by means of a wing component 18, which is set to scrape the waste paper as it turns round the third roller 9.

Only one drive roller, which is advantageously the second roller 7 of the discharge end 16, is required for the conveyor screen 203. Drive device 15 is advantageously connected to this.

Here it is also possible to advantageously use gravity for the tensioning of the conveyor screen. This takes place in such a way that after the rising section, the lower section of travel 25 has two fixed rollers 11 and one roller 12 supported in slide guides, under which the conveyor screen is led. Weighted roller 12 is linked to a weight of a certain size, which is transmitted directly to the conveyor screen.

Claims

Patent Claims

1. A device for removing the waste paper or similar that falls beneath a paper machine, which device consists of an endless continually circulating conveyor screen (3) , and which screen (3) makes possible the blowing of drying air through it, and in which the endless conveyor screen extends essentially over the entire length of the drying section and the discharge end (16) of which is arranged on top of the edge of a pulper (8) which is essentially above floor level (17) , characterized in that the first section (1) of the upper section of travel (4) is arranged essentially horizontally and that in the final section there is arranged the necessary rising section (2) between the first and second rollers (6, 7) , and that the device includes a third roller (9) located further than the first roller (6) , which creates, together with the first roller (6) a backwards directed loop in the upper section of travel (4) , and in which the waste paper is arranged to drop from the third roller (9) onto the rising final section (2) .

2. A device in accordance with Patent Claim 1, characterized in that the device includes a wing component (18) , which is arranged to scrape the waste paper that is turning round the above-mentioned third roller (9) onto the rising final section (2) of the upper section of travel.

3. A device in accordance with Patent Claims 1 or 2 , characterized in that the rotation of the endless conveyor screen (3) takes place through the aforementioned second roller (7) , which is connected to a drive device (15) .

4. A device in accordance with Patent Claims 2 or 3, characterized in that it includes two fixed rollers (4) beneath the aforementioned rising final section (2) , through which the endless screen (3) is guided to travel under an adjustment roller (12) equipped with a standard weight, and that this adjustment roller (12) is attached to vertical slide guides and thus creates a continual tension ^'in the endless screen (3) .