GB967278A - Outriggers for crawler cranes,shovels,hoes and the like - Google Patents

Abstract

967,278. Lifting weight off springs. THEW SHOVEL CO. June 7, 1961, No. 38812/63. Divided out of 967,277. Heading B7D. [Also in Divisions B8 and E1] An outrigger arm for extension from a vehicle such as a mobile crane or excavator into a ground-engaging position in which the vehicle is stabilized against tilt in use, consists of a linearly extensible beam, power means for extending it and friction means for preventing its retraction once it has engaged the ground. The outrigger beam comprises two telescopically retractable tubes 38 and 39, tube 39 being attached by a cross-pin 44 to the piston 43 of an hydraulic actuator 40. The latter when energized pushes tube 39 until its flanged inner end strikes an internal stop (not shown) approximately halfway down the surrounding tube 38 which then moves with the tube 39 until a ground-engaging float 51 at the outer end of tube 39 meets the ground. The float 51, which falls under gravity about perpendicular pivots 49 and 52 to lie parallel with the ground when the outrigger is extended, is guided into the position shown when it is retracted. The radially outer surface of the flanged inner end of tube 39 provides an area of friction contact with tube 38; this, together with a further friction area between the two tubes and between tube 38 and the surrounding fixed mounting 30 (these latter friction areas being provided by flanges at both ends of tube 38), causes the arm as a whole to be self-stable against accidental retraction once the ground has been engaged by float 51. Specification 875,857 also is referred to.