Miniature electric motor for generating vibration

摘要

A miniature electric motor (1) for generating vibration has a rotary shaft (3) having an output portion (4) formed into an irregular shape in cross-section other than a circular cross-sectional shape. An engaging hole (15) having a predetermined cross-sectional shape is formed in a vibrator (5). The output portion (4) is engaged with the engaging hole (15) of the vibrator (5) and the vibrator is positioned and held in a thrust direction relative to the output portion (4) to thereby fix the vibrator (5) to the rotary shaft (3). The cross-sectional shapes of the output portion (4) and of the engaging hole (15) enable the vibrator to be kept relatively non-rotatable relative to the rotary shaft (3). This motor may be used as a vibration generator for a mobile phone.