To provide a swing register capable of easily and properly reducing noise attendant on driving of a blade.

This driving device 10 of the swing register comprises a pinion gear 8 synchronously rotatably connected with an oscillating shaft 4 of a longitudinal blade 5, and a rack gear 13 connected with SMA wires 17a-17d and reciprocating while engaged with the pinion gear 8, and the reciprocation of the rack gear 13 is converted into rotating motion by the pinion gear 8 and transmitted to the oscillating shaft 4.