Permanent magnet alphanumeric display - uses moving belt with moulded pockets on surface and small permanent magnets which fill pockets to form dot matrix style characters

摘要

The display panel uses a moving belt, with a large number of small pockets moulded into its surface, and a small permanent magnets which lodge in these pockets to form complete alphanumeric characters when successive rows of pockets are filled. The belt is carried on an upper and lower motor driven roller. A tray containing small square section ferrite permanent magnets is placed below the lower roller. A permanent magnet runs the full length of the lower roller and draws the small magnets up into the pockets in the belt surface. As the belt turns upwards it faces an array of electromagnets, one for each column of belt pockets. These electromagnets are individually energised so they selectively withdraw the small magnets, leaving only those required to form the characters as the belt moves up into the display area.