Crane with telescopic jib

In a mobile crane including a carriage, an upper chassis, means mounting said upper chassis on said carriage for rotation about an upright axis, a telescopic jib, means pivotally mounting said telescopic jib on said upper chassis for luffing movement about a substantially horizontal axis, a hoist rope, means for winding in and unwinding said hoist rope, a counterweight and means mounting said counterweight for counterbalancing said jib and loads carried from said jib by said hoist rope, the improvement comprising a holding and raising device mounted on said upper chassis, said holding and raising device being operative to pick up from the ground an additional removable counterweight and to hold said counterweight, said holding and raising device includes a strut, said strut being directed away from said jib, means connecting said strut to said jib above said means pivotally connecting said jib to said upper chassis, said means connecting said strut to said telescopic jib is attached to said strut at an end thereof remote from said jib.

In a mobile crane including a carriage, an upper chassis, means mounting said upper chassis on said carriage for rotation about an upright axis, a telescopic jib, means pivotally mounting said telescopic jib on said upper chassis for luffing movement about a substantially horizontal axis, a hoist rope, means for winding in and unwinding said hoist rope, a counterweight and means mounting said counterweight for counterbalancing said jib and loads carried from said jib by said hoist rope, the improvement comprising a holding and raising device mounted on said upper chassis, said holding and raising device being operative to pick up from the ground an additional removable counterweight and to hold said counterweight, said means connecting said strut to said jib includes guy rope means.

In a mobile crane including a carriage, an upper chassis, means mounting said upper chassis on said carriage for rotation about an upright axis, a telescopic jib, means pivotally mounting said telescopic jib on said upper chassis for luffing movement about a substantially horizontal axis, a hoist rope, means for winding in and unwinding said hoist rope, a counterweight and means mounting said counterweight for counterbalancing said jib and loads carried from said jib by said hoist rope, the improvement comprising a holding and raising device mounted on said upper chassis, said holding and raising device being operative to pick up from the ground an additional removable counterweight and to hold said counterweight, said holding and raising device includes a strut means directly connecting said holding and raising device to said telescopic jib, sheave means on said jib and sheave means on said strut, and said hoist rope extending from said upper chassis via said sheave means on said jib and said sheave means on said strut and thence to an upper end of said jib.