GB1100026A - Improvements in and relating to a tea-stalk extractor machine - Google Patents

Abstract

1,100,026. Screening machine. MARSHALL'S TEA MACHINERY CO. Ltd. 16 Nov.. 1964 [15 Nov., 1963], No. 45139/63. Heading B2H. A tea grader and stalk extractor comprises a reciprocatory screen 10, Fig. 3, formed with an array of raised apertured portions 11 over its surface, a majority of the portions each having a plurality of holes 12, 13 formed therein. Preferably all the raised portions have a plurality of holes. The holes are nearer the centre than the periphery of the portions. In the machine shown in Fig. 1, screens 10a, 10b are mounted in oppositely inclined trays 2, 3 which are supported on a frame 1 by means of flexible legs 4, 5 and are reciprocated by means of arms 6, 7 coupled to a crankshaft (not shown) mounted in bearings in an extension 8 of the frame and keyed to pulleys 9 driven through belting by a prime mover. Tea leaves are fed on to the screen 10a from a hopper 14 and the trays are vibrated to shake the leaves first across the surface of the screen 10a and then, in the opposite direction, across that of the screen 10b, an opening (not shown) in the base of the screen 10a adjacent its lower end allowing the leaves to fall on the upper end of the screen 10b. Leaves and mainly stalks from the lower end of screen 10b are collected in a receptacle (not shown). Small sized leaves passes through the holes 12, 13 of the screens 10a, 10b and drop on the bottom parts of the trays 2, 3 and are discharged through chutes 15, 16. The holes in screen 10a may have a different size different from that of the holes in the screen10b.