Multi-motor single-shaft power head

The invention relates to a multi-motor single-shaft power head, and belongs to the technical field of large-hole-diameter and hard-rock layer pile foundation hole formation. The multi-motor single-shaft power head comprises a hanging device (6), more than two low-speed electric motors (1), a middle speed reducer (2), a main gearbox (3), a hollow shaft (5) and an efficient sealing device (4), wherein the hanging device (6) is connected with a pile frame; the more than two low-speed electric motors (1) are connected with the hanging device (6); the middle speed reducer (2) is arranged at the lower ends of the low-speed electric motors (1); each input shaft of the middle speed reducer (2) is connected with the corresponding low-speed electric motor (1); the main gearbox (3) is arranged at the lower end of the middle speed reducer (2); the hollow shaft (5) is engaged with an inner gear of the main gearbox (3) through a gear arranged on the hollow shaft (5); and the efficient sealing device (4) is arranged at the upper part of the hollow shaft (5). The multi-motor single-shaft power head has the advantages that 1, the plurality of motors are used for providing power, and the problems of large-hole-diameter drilling and hard-rock layer entering difficulty are solved; and 2, the plurality of motors share the power, and the phenomena of motor burnt damage and transmission component too-early abrasion or fracture due to reluctant construction are avoided.