Wire belt made of steel wire woven into a flexible web and covered with rub ber is made by the Wire Belt Company, Beaver Falls, Pa. It is claimed to be nine times as strong as a leather belt, and more flexible.
construction of leather-link belts is shown in Figs. 3 and 4. They consist of small pieces of leather of the oblong shapes shown in Fig. 4, with holes near the ends, by which they are connected. These belts are valuable for a variety of purposes. and especially for damp places. They are water-proof, there being no cemented joints to give way by contact with damp ness. By virtue of their weight they are capable of transmitting a considerable amount of power without great width of belt and pulleys. When made with a center-hinge joint they fit laterally to the pulley more completely than solid leather belts, and this quality assists them in the transmission of power. The proper manner of running a link-belt is illustrated in Fig. 3. Here the belt is drawn taut upon the under side, allowing the upper side to sag and climb the driven pulley, so as to bring the belt in contact with a large proportion of its circumference. This large arc of circumference in contact, and the weight of the belt, result in the largest possible amount of power transmitted. Fig. 5 represents a cross-section of the Acme Link-belt, the dotted lines showing the three bolts by which the links are held together transversely ; the three center links, placed upon the highest part of the pulley, as shown, are made V-shaped These form the renter hinge, giving flexibility and adjustability to the belt. At the lines A A are shown the heads of the two bolts, which extend from this ldnge-joint to the outer edge of the belt.
malleable iron links are largely used in bulk-elevating and conveying. and in the transmission of power under suitable conditions. The sizes in common use are designated by 1111111111.N—M he first or first two figures giving approximately the diame ter in sixteenths of an inch of the cud timid side bars of the link, the final figure indicating sequence of the link among those of like strength ; thus, No.41 has side and end in. iu diameter, and is intermediate in other dimensions between No. 42 and No. 45, which are of the same gauge; No. 103 has end-bar Ig in. diameter, and is intermediate in pitch and other
measurements between No. 101 and No. 105. The range of regular sizes is from No. 25, in. pitch length and io in. wide, with working strength of 75 lbs., to No. 160. 10} in. long by 94. in. wide, with working strength of two tons. Tables of working strains" are pub lished by the manufacturers, and all links are subjected to static test of from two and a half to three times these published strains. For power transmission, particularly at the higher speeds, a larger factor of safety should be used, as high as six being desirable when power and speed require use of the heavier links. The following is a list of usual sizes and working strains published by manufacturers: The speed consistent with economy and safety is of course largely dependent on varying conditions. Assuming these to be favorable, it has been found that about 800 revolutions of a wheel whose diameter is five times the pitch length of the links should not be greatly ex ceeded. At low speeds much smaller wheels may be employed, but in no case should a link belt be run on a wheel of less than six teeth.
Applications of link-belting to other purposes than the transmission of power have led to the designing of various attachment forms. These are inserted in the belts at required inter vals, and are employed in elevators, for carrying clips, or buckets, barrel and package arms; in conveyers, for bolting on scrapers or slats: in complete machines, for timed movements ; and in numberless other devices for handling materials. Fig. 6 shows one. form of standard link and the manlier of coupling.
Rope Belliny, commonly riffled Rope Drie ing.—Trausmission of power by ropes has re cently become quite extensively adopted as a substitute for leather belting or line shafting. The necessity for economy of ;Taco in factory work. the growing tendency toward high speeds in steam-engines, and the employment of elec tric motors., have created a demand which rope transmission, when intelligently designed and applied. appears to meet more completely than any other connection between the source of power and its application to the work to be done.