The Mechanical Handling and Storing of Material

7i6 THE MECHANICAL HANDLING OF MATERIAL brought under each bunker as required. The travelling machine is moved along on flanged wheels on a track underneath the bunkers by means of a chain drive actuated from the boiler-house floor. A machine of this type is illustrated in Figs. 1027 and 1028. Automatic coal weighers of larger capacity, say half-ton, or one or two tons per discharge, are also supplied for weighing the intake delivered from barges, railway trucks, etc. The “ Simplex” Grain Scale.—This machine is illustrated in front elevation and side view, Figs. 1029 and 1030. Its mechanism is simple, the working parts are few, and there is not much that is likely to get out of order. A machine weighing 100 lb. at a charge will make about three weighings per minute. It will be seen from the drawing that there is a solid iron ball weight a. In a machine taking charges of 100 lb., this ball will weigh 50 lb., the same as the weight B underneath. The receiving hopper is on the opposite side of the weigh-beam, and when it has received its Figs. 1027 and 1028. Avery’s Portable Weighing Machine, as used at the Boiler House of the Sheffield Corporation Electricity Department. 100 lb. of wheat from the feed hopper c, it tilts up the runners on which the ball a rests, and at the instant the ball moves towards the hopper on its runners it comes in contact with a semicircular lever d, which cuts off the supply; while by the time it has reached the hopper it touches another lever d1, which releases the discharge gate E at the bottom of the hopper and allows the grain to escape. As soon as the skip is empty the runners of the weight tilt up again and the ball begins its return journey. Immediately the ball commences to move in the opposite direction the recipient closes again through the release of a lever d1, and as soon as the ball reaches the terminus it turns the feed on by means of the first-mentioned lever d. There is no time wasted between the weighings, but the most remarkable point about, the machine is this, that it works altogether noiselessly, there being no clicking and engaging of levers in catches, as is the case with many other weighing machines. The discharge door e is practically locked during the drop of the skip, and as there is no connection between the feed gate and the skip, there should be no danger of the discharge gate getting blocked, as the feed gate cannot open during the discharge on account of the heavy ball not being able to return and open the gate until the grain in the hopper has been removed.