WO1997009129A1

WO1997009129A1 - Disc screen rotor

Info

Publication number: WO1997009129A1
Application number: PCT/SE1996/001112
Authority: WO
Inventors: Gustav Fredriksson
Original assignee: Rotom Verkstader AB
Current assignee: Rotom Verkstader AB
Priority date: 1995-09-06
Filing date: 1996-09-06
Publication date: 1997-03-13
Anticipated expiration: 1998-03-06
Also published as: NO980956L; SE506921C2; SE9503071L; NO980956D0; SE9503071D0

Abstract

Disc screen rotor (1) comprising an axle (2) and a set of radially arranged discs (3) fixed onto the axle (2), concentric to its axis of rotation. The axle (2) has a cylindrical section, concentric to its axis of rotation, and which is provided with a set of grooves on its mantle, each of which extends around the whole of its circumference. At least one groove extends along the mantle of the cylindrical section parallel to the axis of rotation of the axle. Discs (3) having a hole, through which the cylindrical section is insertable, are mounted onto the cylindrical part and fitted into a respective circumferential groove in said cylindrical section, and fixed to the cylindrical section.

Description

DISC SCREEN ROTOR

The present invention relates to disc screens, and more specifically to an axle provided with discs, a so-called disc screen rotor, and its structure, for use together with corresponding disc screen rotors in a disc screen.

Disc screen rotors used in present disc screens, comprise an axle, on which discs are arranged side by side. The distance between the discs is set by spacers disposed between every pair of adjacent discs. The discs are held in place by screw joints, which means that a nut arranged on at least one side of the rotor is used to press the discs together when it is tightened, so that they are fixedly located.

The problem with this type of disc arrangement is that tolerance deviations of both discs and spacers entails the variation from time to time of the distance between the respective pairs of discs as well as the distance between the discs located at the extreme ends of the axle. Since a disc screen works thus that the discs of one rotor are rotated in the gap between the discs of an adjacent rotor with the least play possible, the gaps between the discs must be as free of tolerance as possible. In order to adjust deviations so that the discs of the rotors can pass between each other it is necessary, when the deviations are too large, dismount the rotors and start over from the beginning with the mounting of the discs. This makes necessary regrinding of spacers, planing of discs and the like operations demanding a great deal of work, besides the dismounting and the remounting. Since a disc screen is comprised of great number of axles with discs, all which are consequently meant to cooperate, such an adaptation is very time-consuming.

The present invention aims at removing the above-stated problems. This aim is achieved through a disc screen rotor as stated in the appended claims, in which is also stated that, which especially characterises the invention.

The invention is described below together with the accompanying drawings, in which

FIG. 1 is a perspective end view of a disc screen rotor intended for a disc screen,

FIG. 2 is a side view of the axle in fig. 1, with no discs,

FIG. 3 is a cross-section of the disc in fig. 2 along the line III - III, and

FIG. 4 is a perspective end elevation view, broken away, corresponding that of fig. 1, but showing a disc being mounted.

With reference to fig. 1, a disc screen rotor 1 is shown, comprising an axle 2 and, disposed on it, a set of discs 3. The axle 2 is at both its ends provided with spindles 4 and members, not shown, for driven rotation of the disc screen rotor 1. The discs 3 are concentric around the axle 2.

Now with reference to fig. 2 and 3, the axle 2 is shown. Between the spindles 4, the axle has the shape of a cylinder 5, with a circular cross-section and with a diameter which is larger than the spindles 4. In the embodiment shown the cylinder 5 is of a tubular shape. In the mantle of the cylinder grooves 6 are cut around the whole of its circumference. Said grooves 6 are cut with great precision concerning both their position in the longitudinal direction of the cylinder 5, and their width. A number of longitudinal grooves 7, in the shown embodiment four grooves displaced 90° in relation to each other, extend from one end to the other end of the cylinder 5, parallel to its axis of rotation.

The discs 3 have a generally circular shape with a central hole 8. Said hole 8 has a shape corresponding to the cross-sectional shape of the cylinder 5, see fig. 3. The hole 8, which is basically circular, has four elements 9 projecting radially inwards corresponding to the grooves 7.

The mounting of the discs 3 on the cylinder 5 is carried out thus, that one disc at a time is mounted onto the cylinder 5 and moved to the position of the groove 6, where the disc is to be fixed. There the disc 3 is rotated so that the projecting elements 9 enter said groove 6, which rotation in the shown embodiment is approximately 45°. Through the precision of the disc 3 and of the grooves 6 the disc will be disposed in an axially accurate position. The disc 3 may then be fixed onto the cylinder 5, e.g. by means of welding, hard-soldering or any other suitable method.

When the disc screen rotors then are placed in sequence in the disc screen machine no fitting problems will arise, but these will cooperate from the start. Thus the aim set out at the beginning is reached. The design of the discs 3, and especially of the outer peripheral edge, may vary in a number of different ways, depending on e.g. the material to be screened. The number of grooves 7 in the axial direction of the cylinder 5 may also be varied. Such variations are, however, within the scope of the present invention.

Claims

1. Disc screen rotor (1) comprising an axle (2) and a set of radially arranged discs (3) fixed onto the axle (2) , concentric to its axis of rotation, characterised by the axle (2) having a cylindrical section (5) concentric to its axis of rotation, which is provided with a set of grooves (6) on its mantle, each of which extending around the whole of its circumference, by at least one groove (7) extending along the mantle of the cylindrical section (5) parallel with the axis of rotation of the axle (2), by discs (3) having a hole (8), through which the cylindrical section (5) is insertable, are mounted onto the cylindrical section (5) and fitted into a respective circumferential groove (6) in said cylindrical section (5), and by the discs (3) being fixed to the cylindrical section (5) .

2. Disc screen rotor according to claim 1, characterised in that the hole (8) in the discs (3) has a shape, which is congruent with the cross-sectional shape of the cylindrical section (5) .