Patent ID: 6151402
Filing Date: 2000-11-21
Classification: B42D,B60R,G06F,G07F,H04R

Abstract:
A vibration transducer (9) adapted to be mounted on and excite a member (2) having opposed faces and a capability to sustain and propagate input vibrational energy by bending waves in at least one operative area extending transversely of thickness, the vibration transducer comprising:a motor coil assembly (13, 18) having a coil (13) rigidly fixed to a tubular member (18), anda magnet assembly (15), having opposed pole pieces (14), the periphery of one of said pole pieces being disposed within and adjacent to the motor coil assembly, and the periphery of the other of said pole pieces being disposed outside of and adjacent to the motor coil assembly,wherein the magnet assembly has a central attachment portion adapted to be rigidly attached to said member (2) to be vibrated,wherein the motor coil assembly surrounds and is spaced from said central attachment portion of the magnet assembly and has a surrounding attachment portion adapted to be rigidly attached to one face of the member in spaced relation to said central attachment portion of the magnet assembly, andwherein the motor coil assembly and the magnet assembly move in opposite directions when a signal current is applied to the motor coil assembly, whereby the motor coil assembly and the magnet assembly apply a couple to the member when attached thereto through their respective spaced attachment portions to launch bending waves into the member.