Patent ID: 8097986

Claim:
A micro actuator, comprising: a spline shaft formed as a cylinder with a hollow part and having an axially extending slit opening; a spline nut fit-engaged with the spline shaft and axially guiding the spline shaft; a pair of end caps fixed to openings at both ends of the spline shaft; a magnet rod supported at both ends within the hollow part of the spline shaft by the end caps; and a forcer loosely fit-engaged with a periphery of the magnet rod within the hollow part of the spline shaft to constitute a linear motor together with the magnet rod and connected with the spline nut through the slit opening, wherein a linear scale is fixed to the slit opening to extend in a longitudinal direction thereof, and wherein a reading head that is inserted into the slit opening and reads the linear scale is fixed to the spline nut.