Patent ID: 7568559

Claim:
A braking device for a power winch comprising: a reduction box secured on a power winch, said reduction box installed with a reduction gear set in the interior of said reduction box said reduction box having its outer side bored with an accommodating hollow and its center bored with an insert hole for a motor spindle to be inserted therethrough, said reduction gear set received in the interior of said insert hole; a braking lining assembled and positioned in said accommodating hollow of said reduction box; a sectional shaft fitted on said motor spindle and having a first end inserted in said insert hole of said reduction box, said sectional shaft having an annular wall of said first end and a second end formed with teeth, said teeth on said annular wall of said first end, which is inserted in said insert hole, engaged with said reduction gear set for rotating together; an elastic member fitted on said sectional shaft, said elastic member having one end inserted and positioned in a hole of said sectional shaft; a first engraved block fitted on said sectional shaft, said elastic member having a second end inserted and positioned in said first engraved block, said first engraved block disposed with a protruding annular base on one side reverse to said elastic member, said annular base formed with plural corrugated slopes and having its outer wall fixed with two symmetrical actuating projections, said first engraved block having its outer circumferential edge formed with a frictional surface to contact with said braking lining; a second engraved block formed with a central hole having its inner wall provided with teeth to be engaged with said teeth on one said annular wall of said sectional shaft, said second engraved block provided with a slope and two actuating projections respectively corresponding with said plural corrugated slopes and said two actuating projections of said first engraved block, there being slight angle error between said slopes and between said actuating projections of said first and said second engraved blocks; a clutch base bored with an engage hole in the center to be engaged with the outer end of said motor spindle, said engage hole having an outer circumferential edge formed with a bush base that fits a shaft bush thereon, said clutch base having its inner side disposed with two projecting blocks for pushing against said actuating projections of said first and said second engraved block; a reduction box rear cover locked and positioned on said reduction box; and said braking lining being an independent component positioned in said accommodating hollow of said reduction box, said first engraved block pushed to move and have said frictional surface closely contacting with said braking lining to produce braking action when a motor stops operating.