Patent ID: 7857289

Claim:
A tapered braking device for electric winches, comprising: a gear box ( 4 ), fixed on the electric winch; a braking cover ( 13 ), fixedly connected with the gear box; a section of hollow gear shaft ( 2 ), inserted in a shaft hole of the gear box and supported by a bearing; a section of core shaft ( 1 ), extending from a motor shaft and passing through the hollow gear shaft, wherein one extended end portion of the core shaft which extends out of the hollow gear shaft is a polyhedron; a wedge shape piece A ( 9 ), setting on the hollow gear shaft ( 2 ) and engaging with the hollow gear shaft, wherein a left end face of the wedge shape piece A is a cam face ( 16 ) formed by double tapered faces, a right end face of the wedge shape piece A is axially limited by a C-ring ( 10 ), and outer double flange ( 14 ) structure is arranged on the outer surface along a circumference of the wedge shape piece A; a wedge shape piece B ( 8 ), setting on the hollow gear shaft ( 2 ) and still keeping a gap therebetween, wherein a right end face of the wedge shape piece B is a cam face ( 16 ) formed by double tapered faces which engage with the wedge shape piece A, an outer double flange ( 14 ) structure is arranged on the outer surface along a circumference of the wedge shape piece B, and a plurality of braking plates ( 6 ) are disposed on an outer edge of the wedge shape piece B; an elastic element ( 7 ), setting on the section of hollow gear shaft ( 2 ) and abutting against the wedge shape piece B ( 8 ); and a braking clutch base ( 11 ), having a center setting on the end portion of the section of core shaft ( 1 ) and combined with the polyhedron of the end portion, wherein a bearing supports between the braking clutch base ( 11 ) and the braking cover ( 13 ), and an inner double flange ( 19 ) structure is formed on an inner surface of the braking clutch base ( 11 ), matching with the outer double flange structures of the wedge shape piece A and the wedge shape piece B, to push the outer double flange structure of the wedge shape piece A to rotate thereby pushing the wedge shape piece B to move axially; wherein the braking plates ( 6 ) has a double tapered face structure and forms a double tapered friction face with a wedge shape support ( 5 ) which sets on the hollow gear shaft and will rotate along with the hollow gear shaft and the wedge shape piece B ( 8 ) which sets the hollow gear shaft ( 2 ).