摘要 |
A divided bucket type rotary excavator comprises cutter units constructed by dividing a bottomed cylindrical bucket into plural portions, whose curved sidewalls and bottom plates are provided with bits on their leading edges. The cutter units are arranged about a center shaft radially movably toward and away from the center shaft. The center shaft consists of an outer hollow cylinder having a polygonal cross-section and an inner hollow cylinder slidably fitted in the outer hollow cylinder. There is further provided a hydraulic cylinder arranged in the inner and outer hollow cylinders to move the center shaft telescopically, a set of parallel links connecting the outer hollow cylinder to each the cutter unit, and a link having a length one half of that of the parallel links for connecting a middle point of each lower link of the parallel links to a lower end of the inner hollow cylinder, thereby moving the cutter units radially toward and away from the center shaft by telescopically moving the outer and inner hollow cylinders relatively to each other by means of the hydraulic cylinder.
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