Stabilized electromagnetic resonant armature tactile vibrator

An apparatus for generating a tactile vibration in response to an excitation signal, the apparatus comprising:

• a resonant armature system comprising:
• at least two planar suspension members, substantially parallel to each other and separated by a distance, the at least two planar suspension members each comprising a plurality of independent planar spring members arranged regularly about a central planar region within a planar perimeter region;
• a movable mass positioned between and coupled to the at least two planar suspension members for resonating with the at least two planar suspension members at a fundamental mode resonant frequency, wherein the movable mass includes shaped channels formed therein that enable portions of the movable mass to pass freely through apertures in the at least two planar suspension members during operation of the apparatus, thereby allowing a greater mass-to-volume ratio for the resonant armature system than would be possible without the shaped channels;
• and
• a plurality of radially polarized permanent magnets attached to the movable mass for generating an alternating excitation force to produce the tactile vibration in response to an alternating magnetic field;
• and
• electromagnetic means magnetically coupled to the plurality of radially polarized permanent magnets for generating the alternating magnetic field in response to the excitation signal.

An electromagnetic resonant vibrator, comprising:

• a resonant armature system comprising:
• at least two planar suspension members, substantially parallel to each other and separated by a distance, the at least two planar suspension members each comprising a plurality of independent planar spring members arranged regularly about a central planar region within a planar perimeter region;
• a movable mass positioned between and coupled to the at least two planar suspension members for resonating with the at least two planar suspension members at a fundamental mode resonant frequency, wherein the movable mass includes shaped channels formed therein that enable portions of the movable mass to pass freely through apertures in the at least two planar suspension members during operation of the electromagnetic resonant vibrator, thereby allowing a greater mass-to-volume ratio for the resonant armature system than would be possible without the shaped channels;
• and
• a plurality of radially polarized permanent magnets attached to the movable mass for generating an alternating excitation force to produce a tactile vibration in response to an alternating magnetic field;
• an electromagnet magnetically coupled to the plurality of radially polarized permanent magnet for generating the alternating magnetic field in response to an excitation signal;
• and
• a housing physically coupled to the electromagnet and to the resonant armature system for enclosing and supporting the electromagnet and the resonant armature system.

A selective call receiver comprising

• a receiver for receiving radio frequency (RF) signals comprising information and for demodulating the RF signals to derive the information;
• a decoder coupled to the receiver for decoding the received information and obtaining messages therefrom;
• a processor coupled to the decoder for accepting the messages and for generating an alert signal in response thereto;
• and
• an alert device coupled to the processor for generating a vibrating tactile alert in response to the alert signal, the alert device comprising:
• a resonant armature system comprising:
• at least two planar suspension members, substantially parallel to each other and separated by a distance, the at least two planar suspension members each comprising a plurality of independent planar spring members arranged regularly about a central planar region within a planar perimeter region;
• and
• a movable mass positioned between and coupled to the at least two planar suspension members for resonating with the at least two planar suspension members at a fundamental mode resonant frequency, wherein the movable mass includes shaped channels formed therein that enable portions of the movable mass to pass freely through apertures in the at least two planar suspension members during operation of the alert device, thereby allowing a greater mass-to-volume ratio for the resonant armature system than would be possible without the shaped channels.