GB623536A - Improvements in or relating to apparatus for sorting, separating and/or grading articles - Google Patents

Abstract

623,536. Separating solid materials GENERAL ELECTRIC CO., Ltd., RABONE, P., SCRUTON, A. H., and SHERWEN, J. W. April 26, 1944, No. 7785. [Class 117] Articles of the same density for example diamonds or thermionic valve pins are sorted according to shape by feeding the articles on to the delivery zone of a deck of a sorting table vibrating to and fro in one direction, the outer stroke away from the said zone being slightly slower than the return stroke, the deck being substantially flat and of a hard material and being slightly tilted about an axis approximately parallel to the direction of vibration whereby round articles tend to roll in a direction transverse to the direction of vibration, and those articles which have a flat upon their faces or are otherwise prevented from rolling freely tend to slide over the deck in a direction away from the delivery zone. As shown, a table having four flat decks 20, 21, 22, 23 of glass or hard steel with a smooth matt surface is flexibly supported to be vibrated in the direction of 'the arrow 11 by electro-magnetic means, e.g. comprising a fixed electro-magnet having a vibratile armature connected to the rods 12 operating from direct current in conjunction with a switch for making and breaking the energizing circuit of the magnet as the armature vibrates. Alternatively, alternating current without the switch may be used depending upon the desired frequency of vibration. The table is adjustably inclined and the articles to be sorted are contained in a compartment 29 separated from a container by partition 31 and on vibration of the table the articles pass singly through apertures 32, 33 at the base of partition 31 into compartment 30 and thence through apertures similar to 32, 33 provided at the front corners 34, 35 of the compartment 30, when they drop into hoppers 36, 37 fixed to the table and are delivered to the delivery zones of decks 20, 21. Similar arrangements are provided for decks 22, 23. These latter two decks have beneath them a plurality of channels 24 which receive articles that have traversed decks 20, 21 and convey them to receptacles 25, 26, 27 and 28, which also receive, directly, articles from decks 22, 23. To sort the articles, such as diamonds in a manner dependent upon both size and shape, one or more knives 39, Fig. 3, are provided on each deck and are inclined relatively to the direction of vibration away from the delivery zone, the lower edge or edges of the knives being parallel to the surface of the deck 38 and the distance between the lower edges of the knives and the deck decreasing with distance from the delivery zone so that articles having the smaller minimum dimension pass under one or more knives and are arrested by a later one in the direction of travel and are guided by the arresting knife into respective receptacles 44, 45, 46. A receptacle 47 may be provided to receive the articles passing all the knives. The knives 39 may be mounted on a fixed support 43 with the table vibrating relatively thereto. Specifications 355,309. 421,657, 441,733, [Group XXXV], and 481,431 are referred to.