GB190118081A - Improvements in Machines for Drying or Withering Tea Leaf and the like. - Google Patents

Abstract

18,081. Begg, J. Sept. 10. Drying tea.-A chamber for drying or withering tea leaf by natural heat is shown in Fig. 6. A series of rollers J is arranged at each end of the chamber, and the rollers are provided with webs of cloth &c. I, each having a terminal lath I<1> connected by a cord &c. K to a winding-pulley L. The webs may be supported on two or more wires and on intermediate rollers M. The end rollers and pulleys are provided with suitable gearing such as bevel gear o, Fig. 9, rotated by disconnectible bevels P on vertical shafts Q, and ratchet devices S' on the rollers allow them to be locked when required. In operation, the lowest web is pulled through the chamber, and an even layer of tea is deposited on it by a spreader A. Each web is charged in turn, two spreaders being used for a double-ended apparatus, as shown, but a singleended arrangement may be used. The spreaders consist of a hopper A', Fig. 1, having rotary feedrakes B and four linked rocking-shafts D carrying rakes. The shaft may be adjustable. The rocking rakes have teeth which may be adjustable and of different lengths. The spreader may have a pair of hanging aprons to quieten the discharge. Such a spreader may be used for an artificial drying- apparatus in which the tea is spread on the uppermost of a series of overlapping endless bands V, Fig. 13, which are mounted on intermittentlyrotated rollers U*, so that the tea descends stepwise. The tension of the bands may be adjusted by the rollers being carried in adjustable bearings. Fans draw hot air through the chamber, and the air first passes through an endless band Y, moistened by its lower end dipping into a trough, and then passes through an entrance chamber V having porous walls which allow external air to enter. The porosity of the walls is varied according to the state of the atmosphere, and they may be coloured. Additional hot air may be introduced into the chamber by pipes b with bell-mouthed openings c or other means.