The Mechanical Handling and Storing of Material

io6 THE MECHANICAL HANDLING OF MATERIAL inclined, the larger fragments of coal will topple over them, while if they are made higher to prevent this, they require more room for clearing the wagon on the under side. A vertical arrangement would appear to be the most suitable. Wrightson’s coal shipper 1 and Soar’s loader2 may be cited as suitable devices for loading work. A further step towards the solution of the problem is seen in Fig. 136,3 which represents an arrangement devised by Mr S. A. Everett for loading coal down a shoot. The return chain is here arranged above instead of below the shoot, and the obstructing plates, made for lightness’ sake of corrugated metal, fold up on the return side, to economise space. By a kind of cam the flaps are made to open gently as they come over the top tumbler, and being deep, they permit the shoot being lowered to a very steep incline without allowing the coal to fall. For the use of the Zimmer conveyor as a picking and lowering band, see pages 116 and 117. tig. 138. Travelling Trough Conveyor with Single Chain. CONTINUOUS OR ENDLESS TROUGH, TRAY, OR PAN CONVEYOR I his conveyor is practically the same as the metal plate conveyor, with this exception, that each segment has its sides turned up to form a channel, as is shown in big. 137. The endless trough travels over two terminal pulleys, one of which is adjustable to take up the wear in the joints of the chain.4 The sections of trough are also frequently fitted with small supporting rollers which run on angle-bars in the same manner as metal 1 For description of Wrightson’s Coal Shipper see page 600. 2 Soar’s Coal-lowering Apparatus, page 615. 3 From a description of Loading Devices in The Iron and Coal Trades Review, 6th April 1900. 4 See Tightening Gears, page 191.