The Mechanical Handling and Storing of Material

TRANSPORTERS, BRIDGE OR CANTILEVER CRANES 433 crane can be moved at the rate of 3 ft. per second; whilst the movement of the traveller is 13 and 20 ft, per second when moving in an upward and downward direction respec- tively. The capacity is from 300 to 500 tons per day of ten hours, eight or more trimmers being employed to fill the skips. The last of these four transporters was erected at a later date, and was fitted with all the most recent improvements. The rope was guided as shown in Fig. 609, from which it will be seen that the lifting and conveying ropes are running on separate drums. The two winding drums are loose- on the spindle, and are connected by two bevel wheels and four pinions. The four pinions are mounted in a ring which can be fixed or allowed to run loose. All drums are loose on the spindle, and can be coupled to it by friction clutches. This transporter has the advantage of dispensing with the use of more or less complicated fixed stops. It can be stopped and unloaded at any point, and the skip need not be lifted to its topmost position before the traveller is put in motion, for if both conveying and lifting drums are started, the traveller with the skip will rise in an oblique direction, which movement can be utilised to fill the skip from a heap of material lying at its natural angle of repose. The winding gear with its rope connection, shown in Fig. 609, can also be modified in so far that the lifting drum can be dispensed with (see Fig. 610). Such a device is Fig. 609. used by the C. W. Hunt Co., and also by the Brown Hoisting Machinery Co. The ropes are in this case both run over the sheaves in the traveller and secured to the suspender on which the skip hangs. The winding gear works as follows :— The drum 1 is cast together with its driving wheel. It is keyed to the spindle, and can move in both directions. Drum 2 can be coupled to the spindle by the friction clutch r. Both drums receive and pay out rope on the same side, and are coupled together by gearing as shown in Fig. 609. The ring b in which the four bevel pinions are fixed can. be held by a band brake. If the load is to be elevated, both ropes are thrown in, the effect being that both drums revolve in the same direction, and as the four pinions are not fixed, they revolve freely, and are therefore out of action. The load can, by means of the band brake, either be held in suspension or lowered. If the traveller runs either forward or backward, the drums must revolve in opposite directions. The Temperley Transporter.—In conveying coal, grain, and other heavy goods, the Temperley transporter, now manufactured by Sir William Arrol & Co., Ltd., of Glasgow, has undoubtedly rendered excellent service. It is used for the delivery of coal from lighters or barges, as well as from vessels lying at wharves, into boiler-houses, while it has also been found most useful for the loading and unloading of grain vessels. This appliance is so largely used that it is worthy of a full description. Mr Joseph Temperley, the inventor, had for many years been engaged in the shipping industry in 28