Three-degree-of-freedom controllable mechanism type excavator

The utility model relates to a three-degree-of-freedom controllable mechanism type excavator. The excavator comprises a movable arm lifting mechanism, a bucket arm lifting and lowering mechanism, a bucket turnover mechanism, a walking device, a rotation mechanism and a frame. The movable arm lifting mechanism comprises a movable arm and a lifting mechanism; the bucket arm lifting and lowering mechanism comprises a bucket arm and a lifting and lowering mechanism; the bucket turnover mechanism comprises a bucket and a turnover mechanism; and the movable arm, the bucket arm and the bucket are driven by a servo motor arranged on the frame through the lifting mechanism, the lifting and lowering mechanism and the turnover mechanism. According to the three-degree-of-freedom controllable mechanism type excavator, a brand-new connecting rod mechanism is adopted to replace hydraulic transmission, so that the defects that the requirement on manufacturing accuracy of hydraulic components of a hydraulic excavator is high, hydraulic oil is seriously influenced by temperature, faults of a hydraulic system are difficult to check and eliminate and the like are overcome; and moreover, compared with other controllable mechanism type excavators, the amount of connecting rods is reduced, the weight of a connecting rod part is reduced, the stress is improved, and the defects that the connecting rod mechanism is complex and the dead weight is high are overcome.