Variable speed drive for roller shutter door - has speed sensor and impulse-controlled speed regulating computer for acceleration and deceleration of drive

摘要

An electric drive (1) for a roller shutter door is fitted with a reduction gear (2), a speed sensing device (6,8) and a conputer controlled speed regulator (10). The sensor (6,8) is mounted on a secondary output shaft of the reduction gear (2) and comprises a non-magnetic disc (6) in which are mounted magnetic studs (8) equally spaced around its perimeter. A magnetically responsive transmitter enables an impulse count related to drive speed to be fed to the computer (10) thus allowing a presset stepped acceleration and deceleration of the drive to be guaranteed. USE/ADVANTAGE - Safe control of roller shutter door movement. Is positive and safe in action and allows wide range of operation to suit particular application.