GB2136322A - Vibratory concentration table - Google Patents

Abstract

A concentration table for dressing of minerals comprises a vibratory table, the table plate of which is guided for sliding on a plurality of bearings.

Description

SPECIFICATION Rapid percussion table The invention relates to a rapid percussion table for dressing minerals.

In a rapid percussion table hitherto known, the table plate thereof is mounted for oscillation linkage springs with wood or spring-steel leaves.

An eccentric with a stop equipped with springs serves as a drive. This known rapid percussion table is particularly suitable for the dressing or very fine-grained minerals, particularly for the treatment of slurries, a throughput capacity between about 200 and 300 kg/h being achieved with a stroke length up to about 25 mm.Because of the comparatively short travel and the nonplanar movement of the table plate, adequate separation of the desired minerals from the accompanying minerals or the waste cannot be achieved in many cases during the operation of this mechanically driven rapid percussion table, particularly if it is a question of dressing finegrained minerals below 100 y. In addition, in this mechanically driven rapid percussion table, the table plate has to be designed with a separate steel lower structure which not only has a disadvantageous effect from the energy point of view as a result of the masses which have to be accelerated in operation but also impairs the course of movement of the table plate and the associated precision in separation.

The invention seeks to provide a rapid percussion table, particularly with regard to the bearing arrangement and the drive of the table plate, such that a sufficiently precise separation of fine-grained minerals, even under 100 u, can be carried out economically.

According to the invention, there is provided a rapid percussion table for the dressing of minerals, comprising a vibratory table, wherein the table comprises a table plate which is guided for sliding movement on a plurality of bearings.

As a result of this guiding of the table plate for sliding on a plurality of bearings, a purely linear oscillatory movement of the table plate can be achieved very advantageously in operation of the rapid percussion table and, as a result, the vertical forces having a disturbing effect on the separating process are eiiminated.

The table plate may be provided with an hydraulic drive. The hydraulic drive renders possible an increase in the length of stroke of the table plate up to about 50 mm, in a very advantageous manner, which likewise contributes to a considerable improvement in the precision in separation. As a result of the increase in the length of stroke of the table plate, the number of Strokes per unit of time can actually be correspondingly reduced in a simple manner and as a result the period of oscillation of the table plate, that is to say the so-called intervals of rest between two reversal points, can be increased so that even the very fine particles of heavy material under 100 4 present in the feed material have sufficient time to settle to form the lowest layer on the table plate.

Furthermore, as a result of the linear oscillatory movements of the table plate, the forces may be equalized so that the cylinder of the hydraulic drive only needs to take up forces parallel to the movement of the piston rod. In this manner, the cylinder of the hydraulic drive is, to a large extent, saved from wear.

In addition, as a result of the guiding of the table for sliding motion on a plurality of bearings, in comparison with known rapid percussion tables, the table plate can be made comparatively light in weight without a separate steel'lower structure, which leads to a not insignificant reduction in driving energy. A table plate of sandwich construction made of light metal, is particularly suitable for this. Such a table plate may comprise, very advantageously, two cover plates which are disposed spaced apart and which are connected to one another by cells of honeycomb construction.

Such a table plate is distinguished, apart from the very low weight, in particular by its high mechanical stability and satisfactory thermal conductivity. Because of the satisfactory thermal conductivity of the table plate, there is also no distortion of the table plate so that this always remains plane even with severe thermal loading.

This, in turn, renders possible, in a very advantageous manner, a particularly uniform, plane guiding of the table plate on the bearings, which in turn has a favourable effect on the separating process.

The table plate may be guided for sliding motion on aerostatic or hydrostatic bearings. The particular advantage of this mounting of the table plate consists in that these bearings operate substantially completely free of wear and practically without friction. Practical experiments have shown that the driving power necessary for the guiding of the table plate in aerostatic or hydrostatic bearings amounts to only about 1 kW.

The aerostatic or hydrostatic bearings of the table plate may be disposed on a supporting frame of hollow construction which serves to supply static pressure media. In this manner, separate pressure lines for the aerostatic or hydrostatic bearings are avoided very advantageously and, as a result, the rapid percussion table is considerably simplified in construction.

The invention will now be described in greater detail, by way of example, with reference to the drawings, the single figure of which shows, diagrammatically, one embodiment of the invention.

The table plate 1 of a rapid percussion table illustrated in the drawing is guided for sliding on bearings 2 which in turn are disposed on a supporting frame 3 of hollow construction. As a result of the guiding of the table plate 1 for sliding on the bearings 2, a linear oscillatory movement of the table plate 1 is rendered possible in a very advantageously manner and has a favourable effect on the separating process.

The bearings 2 may very advantageously be constructed in the form of aerostatic or hydrostatic bearings. The aerostatic or hydrostatic bearings 2 of the table plate 1, which are disposed on the supporting frame 3 of hollow construction, are very advantageously in communication with one another through pressure lines 4 via which the static pressure media are supplied to the bearings in the direction of the arrow 5. The table plate 2 is further provided with a hydraulic drive 6 which acts on the table plate 1 via a rod 7 and sets this in linear oscillation in one plane.

The table plate is very advantageously made of light metal and is of sandwich construction. It comprises two outer plates 8 and 9 disposed spaced apart and rigidly connected to one another by cells 10 of honeycomb construction. The table plate of sandwich construction made of light metal in this manner not only has a very low weight but also is distinguished in particular by its high mechanical stability and satisfactory thermal conductivity. The table plate therefore remains in operation, retaining its planar shape even with severe thermal loading, which is of significance particularly when the table plate is mounted on aerostatic or hydrostatic bearings.

In the dressing of minerals, not only is a considerable improvement in the precision of separation achieved with the rapid percussion table constructed to the invention, in comparison with the rapid percussion table previously known, particularly with very fine-grained mineral mixtures, but also the rapid percussion table described above renders possible a significant increase in the throughput capacity per unit of time, in a very advantageous manner. According to the invention, it is also possible to develop the hydraulic drive of the table plate for electronic control so that the rapid percussion table can be adapted in the optimum manner to the particular minerals to be dressed, with little expense.

Claims (7)

1. A rapid percussion table for the dressing of minerals, comprising a vibratory table, wherein the table comprises a table plate which is guided for sliding movement on a plurality of bearings.

2. A table as claimed in claim 1, wherein the table plate has an hydraulic drive.

3. A table as claimed in claim 1 or 2, wherein the table plate is guided for sliding movement on aerostatic or hydrostatic bearings.

4. A table as claimed in claim 1, 2, or 3, wherein the table plate has a sandwich construction, made of light metal.

5. A table as claimed in claim 4, wherein the table plate comprises two cover plates which are disposed spaced apart and which are connected to one another by cells of honeycomb construction.

6. A table as claimed in claim 3 or claim 4 or claim 5 when appendent directly or indirectly to claim 3, wherein the aerostatic or hydrostatic bearings of the table plate are disposed on a supporting frame of hollow construction which serves to supply the static pressure media.

7. A rapid percussion table for the dressing of minerals substantially as described herein with reference to the drawing.