Patent ID: 7686150

Claim:
A governor device for door, comprising: an input shaft ( 10 ), having two ends and one end of which receives a driving force from a door machine ( 1 ) to rotate a first gear ( 11 ) and a second gear ( 12 ) provided at two positions on the other end; a hollow shaft ( 20 ), with two ends rotatively pivoted, being provided with a first driven gear( 21 ) correspondingly meshed with the first gear ( 11 ), and the hollow shaft for said first driven gear ( 21 ) serving as a first housing portion ( 22 ) for accommodating and fixing one end of a reel ( 4 ) for winding the door strip panels; a third shaft ( 23 ), with two ends rotatively pivoted, being provided configured with a second driven gear ( 24 ) correspondingly meshed with said second gear ( 12 ), and having an extension shaft ( 25 ) on the end in the same direction of the reel ( 4 ); a brake device ( 3 ), which comprises: an active gear ( 31 ) with its center fixed on the extension shaft ( 25 ) of said third shaft ( 23 ); a passive gear ( 33 ), pivoted on a first hub ( 35 ), and the first hub ( 35 ) being fixed on the reel ( 4 ) and rotated together with the hollow shaft ( 20 ); an idle wheel ( 37 ), located between the active gear ( 31 ) and the passive gear ( 33 ) for adjusting a rotation speed of the passive gear ( 33 ) to be the same as the hollow shaft ( 20 ); and, a clutch mechanism ( 39 ), for restraining a synchronous operation between the passive gear ( 33 ) and the first hub ( 35 ) under no positional difference condition, and when a rotation speed of the reel ( 4 ) has abnormal change, the clutch mechanism ( 39 ) will be actuated to lock the first hub ( 35 ) and brake the reel ( 4 ).