Linear device and electric device with linear motor

An oral hygiene device with a resonant linear motor for providing a linear oscillatory movement along a longitudinal direction comprising:

• a housing;
• a stator comprising a coil core and a stator coil wound around the coil core, which stator is fixedly mounted at or with respect to the housing;
• an armature comprising a permanent magnet arrangement, which armature is mounted for linear oscillatory movement along the longitudinal direction relative to the stator, wherein the permanent magnet arrangement is arranged asymmetrically with respect to the longitudinal axis and has a free end surface facing one side of the stator;
• and
• a drive shaft coupled with the armature, the drive shaft centrically extending along a longitudinal axis parallel to the longitudinal direction;
• wherein the armature has two opposite end sections that are disposed at the longitudinal axis and a central section carrying the permanent magnet arrangement, which central section is offset from the longitudinal axis,
• wherein the resonant linear motor comprises a secondary mass mounted within the housing for linear oscillation along the longitudinal axis to reduce or cancel vibrations transferred from the armature to the housing, and a coupling unit for coupling the armature and the secondary mass, wherein the coupling unit comprises at least two spring assemblies and at least one coupling element, the spring assemblies being arranged in planes substantially perpendicular to the longitudinal direction and being spaced apart from one another, and the coupling element being fixedly connected to the spring assemblies.