GB642284A - Apparatus for sorting small articles - Google Patents

Abstract

642,284. Sorting photo - electrically. FRANKEL, H., and GUNSON (SEEDS), Ltd., R. W. June 16, 1948, No. 16180. [Class 40 (iii)] In a method of sorting small articles described in Specification 617,276, beans, for example, fall one at a time over the metallic tip of an insulated shoot, this end constituting an electrode. As each bean reaches the tip it is examined by a photo-cell and receives a charge from the tip according to its colour so that on subsequently falling between two plates at a high potential difference the charged bean is deflected to a receiving pan. According to the invention the articles are now charged by a corona discharge initiated between a needle 18 and an electrode 19, each individual bean being viewed by a photo-cell 13 as it falls from a shoot 10. In a modification of the invention the corona discharge instead of being initiated by each bean of a predetermined colour may be continuous and may be deflected magnetically away from the path of an article which is not to be charged or vice versa. The light source 12 may be mounted in an internally reflecting spherical housing 20 (Fig. 2), the beans entering through a small hole 21 and leaving through another 22 and the photo-cells being mounted in the side of the sphere as at 23. The article may be fed to the light source by feeding apparatus of the type described in Specification 642,283. They may also be conveyed between adjoining horizontal edges of a pair of inclined belts or between the peripheries of two contact rollers.