Patent ID: 8662140

Claim:
A composite pull-chain disc mechanism with a brake function for a door operator ( 1 ), the door operator ( 1 ) mounted on a base plate ( 2 ) comprising a central shaft ( 10 ), one end of which is provided with an output wheel ( 15 ) for rotating a winding shaft ( 6 ) for a door curtain of slats, and the other end of which is provided with the composite pull-chain disc mechanism ( 30 ) for rotating or braking the central shaft ( 10 ); wherein the composite pull-chain disc mechanism ( 30 ) comprises: a pull-chain disc ( 32 ) rotated by a pull chain ( 320 ), having: an axial space functioning as an accommodating chamber ( 321 ) within the pull-chain disc ( 32 ); a partition plate ( 323 ) fixed on the right side of the accommodating chamber ( 321 ); and a protrudent pin ( 325 ) secured at a predetermined radial point on the partition plate ( 323 ), the left one end of the protrudent pin ( 325 ) axially extending into the accommodating chamber ( 321 ), and the right end of the protrudent pin ( 325 ) extending out of the right side of the partition plate ( 323 ) to form an extending end ( 325 a ); a pair of hubs comprising an inner hub ( 34 ) and outer hub ( 36 ), the inner hub ( 34 ) being pivoted to the partition plate ( 323 ), and in the accommodating chamber ( 321 ), the inner hub ( 34 ) being sleeved within the outer hub ( 36 ), in which the central shaft ( 10 ) passing through the inner hub ( 34 ) and connected therewith integrally; wherein the right end of the inner hub ( 34 ) has a flanged end disc ( 341 ) located at the right side of the partition plate ( 323 ), and on the end face of the end disc ( 341 ), an arc slot ( 342 ) having a predetermined arc length is formed along a circumference direction with a radius in correspondence to the radial position of the protrudent pin ( 325 ) to receive the extending end ( 325 a ); and the left end side of the outer hub ( 36 ) is fixed on the base plate ( 2 ); a movable disc ( 363 ) pivoted around the outer hub ( 36 ); at least one torsional spring ( 38 ), having an inner diameter, and constricting on the outer hub ( 36 ) at the right side of the movable disc ( 363 ), wherein two ends of the torsional spring ( 38 ) are free ends, which are staggered at a predetermined distance in a horizontal direction and formed with radially and outwardly protruding portions ( 381 , 381 ′) respectively; a pair of bolt rods ( 365 , 365 ′), passing from the end disc ( 341 ) of the inner hub ( 34 ) through the partition plate ( 323 ) and passing by outsides, respectively, of the two protruding portions ( 381 , 381 ′) of the torsional spring ( 38 ), and then fixed on the movable disc ( 363 ), wherein the protrudent pin ( 325 ) protrudes in between the two protruding portions ( 381 , 381 ′) of the torsional spring ( 38 ).