Load measuring apparatus for aerial booms and jibs

摘要

A load measuring device for an aerial machine having a boom or jib which handles loads. A load bearing sheave has a winch line passed over it to raise and lower the load. A guide sheave maintains the winch line at a constant entry angle to the load bearing sheave. A dual axis load pin on which the load bearing sheave is mounted measures the force components of the load along two mutually perpendicular axes. Because the entry angle is constant, the load is dependent only on the two measurable force components and can be calculated and displayed. An overcenter machine has two load bearing sheave which are used alternately depending on whether the machine is overcenter or not. Each sheave in this case is mounted on a dual axis load pin.