Patent ID: 7920360
Filing Date: 2011-04-05
Classification: G11B

Abstract:
1. A voice coil motor, comprising: a single external magnet; a primary coil located above the external magnet, the primary coil being capable of receiving a first current; and, at least one torsion compensation coil connected to the primary coil, the at least one torsion compensation coil being capable of receiving a second current; wherein the at least one torsion compensation coil is configured to reduce torsion and/or bending forces introduced by the first current passing through primary coil and/or magnetic field leakage from the external magnet; wherein the at least one torsion compensation coil is looped so as to form a gap between upper and lower portions of the torsion compensation coil; wherein the primary coil comprises a rear leg and an oppposing front leg connected by two side legs, the rear leg and the front leg each including facing inner surfaces; and, wherein the at least one torsion compensation coil is connected to the primary coil at the inner surface of the rear leg of the primary coil.