Linear electric motor drive for drum roller shutter - has sliding braking flywheel splined to axle and moved magnetically to couple with motor

摘要

The transmission system is for use with an electric linear motor (17) power unit, for driving the winding drum of a roller shutter. The system utilises a flywheel (6) mounted to slide axially on the axle (5) of the drum. The flywheel is splined to the axle and acts as both a clutch and a brake, with brake-linings (9) and an armature (10) fixed on opposite annular faces. At rest an adjustable coil sprin (11) maintains the flywheel hard against the housing (12). When the linear motor is energised magnetic forces cause the flywheel to slide until the armature couples with the motor. Alternatively the brake may be separate from the motor, which then acts on metal plates fixed on the edge of the shutter.