US Patent 10428490 Excavator with rigid force transfer link

An excavator includes an articulated boom and a balancing mechanism that assists a movement of the articulated boom from a lower position to an upper position by applying a pulling force on the articulated boom. The balancing mechanism comprises a balancing member that generates an assisting force and a force transfer mechanism that couples the balancing member with the articulated boom. The force transfer mechanism comprises a link mechanism that transfers the assisting force from the balancing member to the articulated boom at a transmission ratio independent from a position of the articulated boom.