DOOR POSITIONING SYSTEM

摘要

A door (10) positioning mechanism (12) with a movable carriage (40) driven by a motor (28) through a lead screw (42), wherein the movable carriage (40) is connected to open and close the door (10) by movement of the door (10) rectilinearly along a track (14) through the expedient of a drive train utilizing a multiple sheave and cable connection between the door (10) and the movable carriage (40). A hand disconnect (32) is provided to disable the positioning mechanism (12) and allow manual movement of the door (10). A thermal (fire switch) dead weight control (38) is also provided to override the positioning mechanism (12) and automatically shut the door (10).