GB748345A - Improvements in and relating to lifting devices for trucks and other self-propelled vehicles - Google Patents

Abstract

748,345. Jib cranes mounted on vehicles. PAYNE, W. H. March 19, 1953 [March 20, 1952 ; Aug. 20, 1952], No. 7667/53. Class 78 (4). The jib of a crane for mounting on a vehicle is pivoted at 13A, Fig. 1, to a vertical hydraulic ram 7, 8 and is connected by a link 19 to a collar 20 turned about the vertical ram to slew the jib by rams 33, 33, Fig. 3, and a lifting cable 26 is reeved around pulleys fixed relatively to the jib and to the collar 20. As illustrated, the crane is mounted by means of a frame 37 on the chassis 38 of a road vehicle. The jib comprises telescoping portions 9, 10, 11 of box section which may be slid manually and locked in desired positions by inserting pins through aligned holes 12, 13, or alternatively may be extended and retracted by a double-acting hydraulic ram which may comprise three or more telescoping sections. The double-acting slewing rams 33, 33 are mounted either at the base of the jib or, as illustrated, on a platform 34 carried by the cylinder 7 of the vertical ram and act through a rack 32, Fig. 4, on a pinion carried by the collar 20. Stops 36, Figs. 1 and 3, limit the extent of slewing. The load hoisting cable 26 passes from an anchorage 30 on the jib under a load block 28, over a jib end pulley 14A and around pulleys 17, 23 carried respectively by the jib and by a bracket 22 on the collar 20 to an anchorage 27 on the jib. Further falls may be provided between the load block 28 and the jib end pulley 14A and between the pulleys 17 and 23. The jib end pulley 14A is mounted in a housing 14 which pivots about a pin 15 on the end of a jib through an extent limited by pins 16. Manual controls 50, Fig. 3, are connected through suitable linkages to valves 45 controlling the rams and connected to a pump 43 mounted in a reservoir 44. The pump may be driven from the power take-off of the vehicle. Rest bars 39, Figs. 1 and 3, slide in collars 41 which are pivoted at 42 to the ends of the frame 37 so that the rest bars may be moved from the position shown in full lines in Fig. 3, in which they abut as their upper ends against the abutment plates 40, to the housed position within the frame 37 indicated in broken lines. The rest bars may be moved between their housed and operative positions by hydraulic rams or hydraulic jacks may be fitted in place of these members.