US Patent 7788988 Drive assemblies

A drive assembly for providing two outputs from a motor to actuators or the like has a first drive shaft connected with the motor via a torque limiter and a reduction gear. A high efficiency spur gear also connects the motor with a second, parallel drive shaft via a second torque limiter and a reduction gear. The two drive shafts are also interconnected by a low efficiency gear provided by worm pinions on the shafts and a worm gear wheel engaging both pinions, which only transfers load between the drive outputs if there is uneven torsional loading in excess of the settings of the torque limiters.