GB737276A - Improvements in and relating to mobile slewing cranes with jibs - Google Patents

Abstract

737,276. Mobile slewing cranes. HEITZ, G. Dec. 1, 1952 [Dec. 1, 1951], No. 30475/52. Class 78 (4). The pillar 5, Fig. 1, carrying the jib 27, 31 of a mobile pillar crane is universally mounted so that it may be adjusted to compensate for irregularities in the ground or to facilitate slewing in a preferred direction. In the embodiment of Figs. 1 and 2 the universal mounting 3, 4 is carried by a spider 2 secured to the longitudinals of a vehicle chassis and is apertured to pass the column 5 which is connected by a ball joint 7 at its lower end to a pair of blocks 9, 91 secured together and sliding vertically in a nut 10 which is traversed along a U-section guide rail by a screw 11 turned by a crank 15. The shaft of the screw 11 is journalled in blocks 12, 12<SP>1</SP> which are slid along guides 13, 13<SP>1</SP> when screws 16, 16<SP>1</SP> are rotated by a crank 20 and bevel gearing 21<SP>1</SP>, 22<SP>1</SP>, 21, 22. The column 5 may thus be adjusted to any desired inclination. Its inclination from the vertical is indicated by the position of a plumb bob 37 over an indicator 38. When the crane is in use bars 34, 34<SP>1</SP>, 35, 35<SP>1</SP> may be slid out of housings and supported at their ends by jacks. In the construction of Figs. 3 and 4 the inclination of the pillar 106 is adjusted by nuts 113, 114 engaging screws 115, 116 anchored to reinforcing bars 121, 122 above the driver's cab 102 of a vehicle. The nuts 113, 114 terminate in yokes 111, 112 by which they are pivoted to rings 107, 108 rotatably mounted on the pillar. The screws 115, 116 terminate in balls 117, 118 mounted in housings 119, 120 and restrained from movement about a vertical axis by tongues 119<SP>1</SP>, 120<SP>1</SP> which engage slots in the balls. The housings 119, 120 are pivoted about vertical axes. The tie 124 shown supporting the jib 123 may be secured to the upper end of the pillar 106 as shown or may pass down the interior of the column to a winch mounted below the universal joint 104, 105. In a further embodiment the adjustable links 113, 115 and 114, 116 are secured to a portion of the pillar 106 extending below the universal joint and may be replaced by hydraulic pistons and cylinders selectively controlled. The jib may be telescopic and supply pipes for effecting the variation in its length hydraulically may pass through the interior of the pillar 106. The ball joints 7, 9, 9<SP>1</SP> and 104, 105 may be replaced by gimbal mountings.