Modern mechanism, exhibiting the latest progress in machines, motors, and the transmission of power, being a supplementary volume to Appletons' cyclopaedia of applied mechanics (1892) (14746659006)

Identifier: modernmechanisme00benj (find matches)
Title: Modern mechanism, exhibiting the latest progress in machines, motors, and the transmission of power, being a supplementary volume to Appletons' cyclopaedia of applied mechanics
Year: 1892 (1890s)
Authors: Benjamin, Park, 1849-1922
Subjects: Mechanical engineering
Publisher: New York, D. Appleton
Contributing Library: Mugar Memorial Library, Boston University
Digitizing Sponsor: Boston University



Text Appearing Before Image:
(> and 7) illusliate a mpe-driven traveling-crane madeby the IMiiladelphia Kngineering Works. In this cr.-inc ropes and belts are used as far aspossible, instead of gears and shafting. Tlie trolley has the full traverse molion of the l)ridge.The power is applie(l by two endless cotton ropes (.5, T)) extending along the full length of theshop, In-ing guided by pulley-wheels at intervals. These ropes arc ke;il taut on one end bypassing over a movable sheave suspended \i;)(in guide-bars, and pass over driving-sheaves (G, 7)placed /ig/ag in relatinn to a fiair of guide-sheaves, upon either sideof the main girders(l. 1). CEANES. 159 By this arrangement a long grip on the driving-sheaves is obtained. One of these driving-sheaves (6) is fitted to a shaft, working in adjustable bearings, and carrying three pulleysfor the lifting-gear. The j)o\ver is transmitted from these pulleys, through belts, to acounter-shaft (13) fitted up with three sets of tight and loose pulleys, thereby obtaining
Text Appearing After Image:
Fig. 6.—Rope-driven traveling-crane. three lifting and three lowering speeds. From this counter-shaft (13) the motion is trans-mitted, through a pair of spur-gears, to a square shaft (21) (provided with tumbling bearings),extending the full length of tlie bridge (1). The motion is then transmitted to the lifting-drum(23). from any part of the squareshaft (31), by means of tangentgear (24 and 25) carefully cut byspecial macliinerv, and spur-gears(26, 27). The sides of the trolley(28) are made of cast iron, securedto each other by distance boltsand bars (28, 29). The drum (23)is made of cast iron, and has aright and left luinded groove forthe chains. By this arrangementthe load always hangs in the cen-ter, between the girders. A driv-ing-sheave (7) is fitted to a shaft(33) working in adjustable ball-bearings (34), and carrying fourpulleys, two for giving motion tothe bridge (1) up and down theshop, and two for giving trans-verse motion to the trollev. The