Functional Analysis Based Conceptual Design of a Type of Novel Mechanical Excavator with Controllable Mechanism

摘要

Excavators can be divided into two categories: hydraulic excavator and mechanical excavator. Due to the flexibility and mobility, hydraulic excavator has almost replaced the mechanical excavator. But there still exists some problems such as hydraulic leaks and high costs of manufacturing and maintaining. On the other hand, the latter one is the excavator of choice in oil sands digging and surface mining for its durability, high productivity and low ownership costs resulting from long economic operating life, but lacks flexibility due to the structural limitations. This paper introduces an innovative design of mechanical excavator with controllable mechanism based on functional analysis of the traditional hydraulic excavator. The solving model in the form of Function-Effect-Technical Action Process-Executive Action-Mechanism (F-E-P-A-M) is used. A planar 2 Degree-OF-Freedom (DOF) controllable mechanism is adopted as the executive mechanism. A backhoe type and a face shovel type excavator both with the ability to accomplish flexible output trajectories by the joint operations of three servo-motors are proposed.