Drive Unit For Raising And/Or Lowering A Roller Shutter

A drive unit for a roller shutter assembly, the roller shutter assembly having an axle and a roller shutter connected thereto, the drive unit including:

• (a) a reduction gear train including an input gear and an output gear, the reduction gear train being arranged so that the output gear is responsive to rotation of the input gear to thereby rotate an axle engaging means for winding the roller shutter onto or off the axle;
• (b) at least two electric motors, each electric motor having an output shaft;
• and
• (c) for each electric motor, a coupling means mechanically coupling the output shaft of a respective electric motor with the input gear;
• wherein each of the electric motors is operable to generate mechanical power, and wherein the mechanical power generated by the combination of the electric motors causes rotation of the input gear.

A multistage drive unit for winding a roller shutter onto and off an axle, the drive unit including:

• (a) a primary stage module including:
• i. a first gear train including a primary stage input gear and a primary stage output gear;
• and
• ii. at least two electric motors for generating a mechanical power for rotating the primary stage input gear, the first reduction gear train being arranged so that the primary stage output gear is rotationally responsive to rotation of the primary stage input gear;
• (b) a secondary stage module including a second reduction gear train including a secondary stage input gear and a secondary stage output gear, the secondary stage input gear for engaging with the first or primary stage's output gear, the secondary stage output gear for transferring a torque for winding a roller shutter onto and off an axle;
• and
• (c) a support means for supporting the first or primary stage module and the secondary stage module so that the primary stage output gear engages with the second or secondary stage input gear;
• wherein the gears of the primary stage module have improved precision relative to the gears of the secondary stage module.

A removable primary stage module for a roller shutter drive unit, the primary stage module including:

• (a) at least two electric motors;
• (b) a reduction gear train including an input gear and an output gear, the at least two electric motors for generating mechanical power for rotating the input gear, the output gear being rotationally responsive to rotation of the input gear;
• (c) for each electric motor, a coupling means mechanically coupling the output shaft of a respective electric motor with the input gear;
• and
• (d) a housing means housing the at least two electric motors and the first reduction gear train.

A roller shutter assembly including:

• (a) an axle;
• (b) a roller shutter connected to the axle;
• and
• (c) a drive unit for winding the roller shutter onto or off the axle, the drive unit including at least two electric motors having an output shaft mechanically coupled to an axle engaging means via a reduction gear train;
• wherein each of the electric motors is operable to generate mechanical power, and wherein the mechanical power generated by the combination of the electric motors is coupled to the axle engaging means via the reduction gear train to wind the roller shutter onto or off the axle.