establishment of the wagenschaltwerk for typewriters to address the schaltklinkengeraeusches during the wagenaufzuges

摘要

697,725. Level luffing jib cranes. NAAMLOOZE VENNNOOTSCHAP MACHINEFABRIEK JAFFA VORHEEN L. SMULDERS & CO. Dec. 7, 1949. [Dec. 21, 1948] No. 31428/49. Class 78 (iv). A luffing crane in which the jib 10, Fig. 4, is bent at 12 to permit it to be luffed through the vertical while carrying a load, has level luffing gear which comprises a link 34 (shown diagrammatically in Fig. 5) connected below the heel pivot 11 to the jib and operating a vertically sliding rack F which drives a pinion G connected by a differential gear to apply a correcting movement to the hoisting winch. The differential gear is shown in Fig. 6 and comprises a sun wheel 21 driven by a pinion 20 from the hoist motor 18, a planet carrier 26 driven through gears 31, 33 from the pinion G, and a sun wheel 24 which drives the hoisting winch 29 through gears 27, 28. The jib is luffed by a pair of toothed segments 15, Fig. 4, carried on the balance arm 13 of the jib and engaged by driving pinions (not shown). The operator's cabin 36 is mounted at one side of the slewing platform of the crane. The hoisting cable 40 is guided along the centre line of the bent jib while the jib end pulley 41, Fig. 7, is carried by a hollow tube 37 through which the cable 40 passes and which is carried by bearings 38, 38, 39 in the jib.