GB911978A - Improvements in or relating to the processing of edible crustacea - Google Patents

Abstract

911,978. Separating solid materials. ASSOCIATED FISHERIES & FOODS (FLEETWOOD) Ltd. Jan. 31, 1961 [Oct. 31, 1959], No. 37017/59. Class 117. A machine for grading and sorting shrimps, crayfish or prawns, and particularly the latter from which the head and legs, and possibly the tail-fins, have been removed, comprises one or more pairs of downwardly inclined diverging rotating rollers 7 on which the prawns are caused to traverse lengthwise so that they fall between the rollers and on to transverse conveyer belts 31, 32 at positions dependent on their transverse dimensions. The rollers are supported in a framework 2, 3, and each roller is mounted on a spindle 9 and consists of a parallel sided part 7a with helical ridges at the input or feed end, followed by a tapering part 7b also with helical ridges, and a parallel-sided part 7c at the opposite end. The spindles are supported in transverse bars 5, 6 and have intermeshing driving pinions 12 at their input ends so that all the spindles rotate together. The parts 7b and 7c of each roller are integral and fixed to the spindle, whereas the part 7a is rotatable on the spindle and is driven at a slower speed by a pinion 20. The direction of rotation of each roller of a pair is such as to prevent the fish being carried into the " nip." A flicker roller 8 is associated with each feed roller ; it is mounted between support bars 4, 5 and driven in the same direction by a driving band 8a. The flicker rollers have longitudinal ridges and keep the fish in the space between adjacent rollers. As shown in Fig. 8, partitions 38 extend from longitudinally adjustable supports 39 to adjacent the transverse conveyer belts 31, 32, and define adjustable paths for the falling fish and thereby the size of fish received at each conveyer. A photo-electric cell may scan each prawn just prior to its delivery to the sorting and grading apparatus so that undersized and damaged prawns are detected and removed by an air blast or other means. The machine may be used in combination with the fish processing apparatus of Specifications 911,976 and 911,979.