GB2098525A - Treatment of planar articles - Google Patents

Abstract

Articles, e.g. metal discs, to be stacked one upon the other are each provided with an irregular array of protrusions on at least one of a pair of opposite surfaces thereof. Preferably, the array of protrusions is provided by passing each of the articles between a pair of pinch rolls (4', 4'') of which one (4') has an array of protrusions (10) upon its cylindrical surface and the other (4'') has an array of distributed indents (11) in its cylindrical surface, the rolls (4', 4'') being rotated in such a manner that the protrusions (10) of the one roll (4') register with the indents (11) of the other roll (4''). <IMAGE>

Description

SPECIFICATION Treatment of planar articles This invention relates to the treatment of planar articles which are to be subsequently stacked one upon the other and then removed from the top of the stack in a sequential manner one by one.

It is generally known that planar articles, such as discs of metal, having comparatively smooth surfaces, are extremely difficult to remove individually from a stack of such articles. This is because the adjacent stacked planar articles tend to "adhere" to one another owing to the confronting smooth surfaces being in intimate contact, eliminating any air gap between adjacent planar articles. Additionally; if the smooth surfaces of the stacked articles are coated with a wetting agent, such as, in the case of metal discs, a soluble oil, then this adherence between adjacent articles is increased considerably, mainly due to the surface tension effect of the wetting agent.

The present invention sets out to provide a method of and apparatus for treating planar articles, whereby, after the treated articles have been stacked one on top of the other, they can easily be removed from the stack top.

In accordance with one aspect of the invention, there is provided a method of treating planar articles to be subsequently stacked one upon the other, which method comprises providing a random array of protrusions on at least one of a pair of opposed surfaces of the articles.

In accordance with another aspect of the invention, there is provided an apparatus for treating planar articles to be subsequently stacked one upon the other, which apparatus comprises cooperating means for forming a random array of protrusions on at least one of a pair of opposed surfaces of the articles.

The cooperating means preferably comprises a pair of pinch rolls, one having an array of randomly distributed protrusions upon its cylindrical surface and the other having an array of randomly distributed indents in its cylindrical surface. The rolls may be arranged such that, upon rotation thereof, the protrusions of the one roll register with the indents of the other. Alternatively, the other roll can have a smooth cylindrical surface and the protrusions of the one roll are arranged such that they provide the necessary protrusions in one surface of the planar article. A further alternative is to provide each roll with an array of randomly distributed protrusions and indents in its cylindrical surface, with respective pairs of protrusions and indents on the rolls registering with each other along the line of contact of the rolls.

Before the article, such as a metal disc, is passed between the pinch rolls, any liquid remaining on the surfaces of the disc from a previous manufacturing step may be removed or substantially removed by passing the disc through at least one pair of squeeze or pinch rollers. For instance, the metal disc can be passed initially between a pair of pressure rollers made of, say, a hard metal, which remove or flatten any burns on the circumference of the disc and, also, remove at least some of any liquid, such as soluble oil, on the surfaces of the disc. Subsequently, the disc is passed between a pair of rubber surfaced rollers which act as a type of "squeegy' to remove all or substantially all of the remaining liquid.

Any small amount of liquid, which may remain on the disc surfaces after the disc has been passed between the second pair of "squeegy" rollers, can be removed by evaporation before the disc is passed between the pair of projection-forming rolls. The evaporation of the remaining liquid is preferably effected by means of a jet of hot air from appropriate application means located between the pair of "squeegy" rollers and the pair of projection-forming rolls.

In order that the invention may be more fully understood, a preferred form of apparatus in accordance therewith will now be described by way of example with reference to the accompanying drawings in which: Fig. 1 is a schematic side view of apparatus for treating metal discs which are to be subsequently stacked and then removed individually from the top of the stack; Fig. 2 is a partial cross-section view of a pair of rolls of the apparatus of Fig. 1; Figs. 3 and 4 are respective plan and side views of a disc which has been treated by the apparatus shown in Figs. 1 and 2; and Fig. 5 is a side view of a stack of discs as shown in Figs. 3 and 4.

Referring to Figs. 1 and 2, apparatus 1 , for treating metal discs which are to be stacked and subsequently removed individually from the top of the stack, comprises two pairs of rollers 2', 2" and 3', 3" and a pair of pinch rolls 4', 4". The rollers and rolls are rotatable about horizontal axes and the rollers 2' and 3" and the pinch roll 4' are rotated by a driven continuous belt 5. The roller 2', in turn, rotates the roller 3' by means of another continuous belt 6, whilst the roller 3" rotates the roller 2" and roll 4" via respective drive belts 7 and 8.

The rollers 2', 2" have hard metal contact surfaces which engage with each other in line pressure contact, such that, when a metal disc to be treated is passed therebetween, some of any soluble oil or other liquid on the surfaces of the disc from a previous manufacturing process is removed and, also, any burrs on the disc from that previous process are removed.

The disc is then passed between the roller pair 3', 3" which are provided with rubber contact surfaces such that, as the disc passes therebetween, any soluble oil or other liquid remaining on the disc surfaces is removed or substantially removed therefrom. This pair of rollers 3', 3" act as a type of "squeegy".

If any soluble oil or other liquid remains on the metal disc surfaces after the disc has been passed between the roller pair 3', 3", then it is evaporated from these surfaces by a jet of hot air from each of a pair of nozzles 9 located on opposite sides of the path of the disc between the rollers 3', 3" and rolls 4',41'.

Subsequently, the "dry" and deburred disc is passed between the rolls 4', 4" which are provided with random arrays of projections 10 and indents 1 1 on their surfaces. Corresponding pairs of projections 10 and indents 1 1 on the rolls 4', 4" register with each other along the line contact of the rolls, such that the disc is provided with an array of corresponding projections and indents on its two surfaces.

In Figs. 3 and 4, there are shown respective plan and side views of a disc 14 treated with the apparatus described above with reference to Figs.

1 and 2. As can be seen, the surfaces 12, 13 of the disc 14 are provided with a random array of corresponding pairs of projections 12', and indents 13' which have been formed between the pair of pinch rolls 4', 4".

Referring now to Fig. 5, a stack of dry treated discs 14 clearly illustrates that a small air gap 20 is provided between adjacent discs by the separation of the discs due to the projections 12', 1 3' on the surfaces 12, 13 of the discs.

The array of projections is random such that none of the indents 12", 13" of one disc coincide with projections 12', 13' of an adjacent disc, otherwise no disc separation would be provided.

Thus, it can be seen that the air gap 20 between adjacent discs 14 allows the discs to be removed individually from the top of the stack 1 5 of discs, without there being any "sticking" of the discs to each other, as described above and in the case of the discs having smooth surfaces.

Claims (18)

1. Apparatus for treating planar articles to be stacked one upon the other, comprising cooperating means for forming a random array of protrusions on at least one of a pair of opposite surfaces of each of the articles.

2. Apparatus according to claim 1 , wherein said cooperating means comprises a pair of pinch rolls of which one has an array of randomly distributed protrusions upon its cylindrical surface and the other has an array of randomly distributed indents in its cylindrical surface, the rolls being arranged such that, upon rotation thereof, the protrusions of the one roll register with the indents of the other roll.

3. Apparatus according to claim 1, wherein said cooperating means comprises a pair of pinch rolls of which at least one has an array of randomly distributed protrusions upon its cylindrical surface.

4. Apparatus according to claim 3, wherein one only of the pair of pinch rolls has an array of protrusions randomly distributed upon its cylindrical surface, whilst the other pinch roll has a smooth cylindrical surface.

5. Apparatus according to claim 2, wherein said one pinch roll has also an array of randomly distributed indents in its cylindrical surface and the other pinch roll has an array of randomly distributed protrusions on its cylindrical surface, the rolls being such that, upon rotation thereof, the protrusions and indents of the one roll register with respective indents and protrusions of the other roll.

6. Apparatus according to any preceding claim including at least one pair of pinch rollers upstream of said cooperating means for removing any burrs and/or at least some of any liquid on the surfaces of the planar articles.

7. Apparatus according to any preceding claim, including means for evaporating at least some of any liquid on the surfaces of the planar articles.

8. Apparatus for treating planar metal discs substantially as hereinbefore described with reference to Figs. 1 and 2 of the accompanying drawings.

9. A method of treating planar articles to be stacked one upon the other, which method comprises providing a random array of protrusions on at least one of a pair of opposite surfaces of each of the articles.

10. A method according to claim 9, wherein the random array of protrusions is provided by passing each of the articles between a pair of pinch rolls of which one has an array of randomly distributed protrusions upon its cylindrical surface and the other has an array of randomly distributed indents in its cylindrical surface, the rolls being rotated in such a manner that the protrusions of the one roll register with the indents of the other roll.

11. A method according to claim 9, wherein the random array of protrusions is provided by passing each of the articles between a pair of pinch rolls of which at least one has an array of randomly distributed protrusions upon its cylindrical surface.

12. A method according to claim 1 wherein one only of the pair of pinch rolls has an array of protrusions randomly distributed upon its cylindrical surface, whilst the other pinch roll has a smooth cylindrical surface.

13. A method according to claim 10, wherein said one pinch roll has also an array of randomly distributed indents in its cylindrical surface and the other pinch roll has an array of randomly distributed protrusions on its cylindrical surface, the rolls being rotated such that the respective protrusions and indents of the two rolls register with each other.

14. A method according to any of claims 9 to 13, wherein any burrs and/or at least some of any liquid on the surfaces of the planar articles are and/or is removed before the random array of protrusions is provided on at least one surface of each article.

15. A method according to any of claims 9 to 14, wherein at least some of any liquid on the surfaces of the articles is caused to be evaporated therefrom.

16. A method according to claim 15, wherein said evaporation is caused by a jet of air directed at the surfaces of the articles.

17. A method of treating planar metal articles substantially as hereinbefore described.

18. A planar article when treated by a method according to any of claims 9 to 17.