GB2084490A - Article separators - Google Patents

Abstract

A separator for use in separating sprues from moulded articles comprises at least two parallel axles (1, 3, 5) upon each of which a number of wheels (18, 20, 22) are eccentrically mounted, the wheels on adjacent axles overlapping each other. Each wheel has an indented periphery. The wheels on adjacent axles (1, 3; 3, 5) are preferably arranged to reach top dead centre simultaneously. Thus, by virtue of the indented periphery of each wheel and the fact that the configuration of the trough formed between overlapping wheels on adjacent axles varies cyclically, more efficient transfer of the sprues is achieved. <IMAGE>

Description

SPECIFICATION Improvements relating to article separators The present invention relates to a separator for use in separating articles.

In particular the present invention relates to a separator for separating finished articles or components made of a plastics material, from the sprues and runners also produced during moulding.

During the injection moulding of plastics articles or components wherein a number of articles are manufactured simultaneously, molten plastics material is fed along narrow passageways interconnecting moulding cavities. When the mould has cooled and is opened the moulded articles are interconnected by sprues of plastic which has set within the passageways. So-called submarine gates are used to sever the sprues from the articles, and the articles are then moved together with the sprues, onto a conveyor for subsequent separation. The sprues are elongate lengths of plastic material, which are usually considerably longer than the required articles.

Thus it is possible to effectively filter the articles from the sprues.

One known piece of apparatus for filtering the sprues from the associated articles utilises overlapping rows of rotating wheels, the articles falling between the wheels to a collection region and the sprues passing over the wheels to a further collection region for recycling. In practice however, whilst the articles do pass between the wheels, the sprues tend to collect between adjacent rows of wheels so that the sprues are not continuously passed to the collection area and often manual clearing of the sprues from the trough defined between adjacent rows of wheels, is required.

The aim of the present invention is to provide a separator for use in separating sprues from finished articles or components wherein the sprues more readiiy pass to the collection area.

According to the present invention there is provided a separator for use in separating sprues from moulded articles comprising at least two parallel axles upon each of which a number of spaced apart wheels are eccentrically mounted, the wheels of adjacent axles overlapping each other and having an indented periphery.

Thus, by virtue of a separator constructed according to the present invention the sprues are conveyed across the rows of wheels to a collecting station, the eccentric motion of the wheels causing the configuration of the trough formed by overlapped wheels, to cyclically change and so induce the sprues to move, aided by the indented periphery of the wheels.

In a preferred embodiment of the present invention, the separator comprises three parallel axles, the wheels on the axles having a sinusoidal indented periphery. Preferably the wheels on each axle are driven by a common motor and are arranged to simultaneously all reach top dead centre. Alternatively, the wheels on adjacent axles may be out of synchronisation. Preferably four wheels are provided on the two adjacent axles on the input side of the separator, one wheel on one axle overlapping between two adjacent wheels on the other axle, and a much larger number of wheels are provided on the third axle on the output side of the separator. Alternatively any number of wheels may be provided on the axles, the main criterion being that the articles can pass between adjacent wheels on the input side of the separator Thus the separator can be any desired width.Further, the wheels are preferably all the same size though wheels on adjacent axles may differ in size if required.

Preferably the separator of the present invention is arranged at the end of a conveyor to feed the sprues to a granulator wherein the sprues are ground up ready for recycling. To prevent the granulator from effectively back-firing or throwing the sprues back out due to the grinding action, the separator preferably feeds the granulator via a rotating paddle wheel arrangement which closes off the granulafor inlet.

The present invention will now be further described, by way of example, with reference to the accompanying drawing in which a preferred embodiment of separator constructed in accordance with the present invention is shown schematically and partially cutaway, in conjunction with a conveyor and a schematically illustrated granulator.

The separator illustrated in the accompanying drawing comprises three parallel axles 1, 3 and 5 which are rotatably driven by motor 7 via chains or belts 9, 11, 13 and 1 5. Axle 1 is iocated adjacent the exit end of a conveyor 1 7 and carries four eccentrically mounted wheels 1 8 which are spaced apart from each other and which each have a sinusoidally indented periphery. Axle 3 carries three eccentrically mounted wheels 20 which also have a sinusoidally indented periphery, each of the three wheels 20 engaging between two adjacent wheels 1 8 on axle 1. Axle 5 carries a multiplicity of eccentrically mounted wheels 22, each wheel again having a sinusoidally indented periphery, a number of wheels 22 engaging between each pair of adjacent wheels 20 on axle 3 to provide the desired overlap.The wheels 18, 20 and 22 are all of like dimensions e.g.

1 50 m.m. diameter, with the same eccentric mounting e.g. 5 m.m. Also the axles are rotationally arranged with respect to the drive by motor 7, so that all of the wheels 18, 20 and 22, attain the top dead centre position simultaneously.

Alternatively, the wheels of the separate axles can be of different dimensions, different eccentricity and/or out of phase. However, the eccentric arrangement causes the troughs produced between adjacent rows of overlapping wheels to change with regard to their configuration, thus inducing the sprues to pass thereover with the aid of the indented wheel peripheries.

The separator is arranged at the exit end of feed conveyor 17, the articles (not shown) passing from the conveyor 1 7 between wheels 1 8 into a collection bin 24 and the elongated sprues (not shown) passing over the sheels, 1 8, 20, 22 of the separators to a granulator 26 of known construction wherein the sprues are ground up ready for subsequent recycling. To prevent the sprues from being thrown back out of the granulator 26 by the grinding action of the granulator a paddle wheel feeder 28 is provided which is also driven by motor 7 and which effectively closes off the granulator inlet.

Whilst the above described separator constructed according to the present invention, utilises a specific number of transfer wheels on axles 1 and 3, any desired number of wheels can be provided within the scope of the present invention, the sole criterion being that the wheel spacing on axle 1 is sufficient to allow the said article to pass therethrough to the collection bin 24. Thus it is clear that the separator can be constructed with any desired width.

The present invention thus provides an improved separator whereby the sprues can be more efficiently conveyed away for recycling.

Claims (11)

1. A separator for use in separating sprues from moulded articles comprising at least two parallel axles upon which a number of spaced apart wheels are eccentrically mounted, the wheels of adjacent axles overlapping each other and having an indented periphery.

2. A separator as claimed in claim 1, in which the wheels on each axle are driven by a common motor.

3. A separator as claimed in claim 1 or claim 2, in which the eccentrically mounted wheels on each axle are arranged to simultaneously all reach top dead centre.

4. A separator as claimed in any one of the preceding claims, in which three axles are provided and the two adjacent axles on an input side of the separator having only one wheel on one axle overlapping between two adjacent wheels on the other axle, whilst a larger number of wheels are provided on the third axle forming an output side of the separator, more than one wheel on said third axle overlapping between adjacent wheels on the middle axle.

5. A separator as claimed in claim 4, in which four wheels are provided on each of said two adjacent axles on the input side of the separator.

6. A separator as claimed in any one of the preceding claims, in which the wheels each have a sinusoidally indented periphery.

7. A separator as claimed in any one of the preceding claims, in which the wheels are the same size on all of the axles.

8. A separator as claimed in any one of claims 1 to 6, in which the wheels on adjacent axles are of a different diameter.

9. A separator as claimed in any one of the preceding claims, in which the separator is arranged at the end of a conveyor to feed sprues to a granulator for recycling.

10. A separator as claimed in claim 9, in which the separator feeds the granulator via a rotating paddle wheel arrangement which closes off the granulator inlet.

11. A separator for use in separating sprues from moulded articles, constructed and arranged substantially as hereinbefore described with reference to and as illustrated in the accompanying drawing.