Electrical/mechanical/sound converter and apparatus of electrical/mechanical/sound conversion

An electro-mechanical/audio converting device comprising:

• an amplifier;
• an electro-mechanical/audio converter including a housing having a first opening end and a second opening end, a movable part including a magnetic circuit, a suspension for mounting said movable part on said housing near said first opening end for supporting said movable part so that it is movable, a vibrating plate mounted on said housing near said second opening end, said vibrating plate being disposed away from said movable part, a voice coil whose top end is connected to said vibrating plate and whose bottom part is inserted in a magnetic gap of said movable part, and a detection coil wound around said housing and disposed near said movable part, said detection coil generating excitation voltage by vibration of said movable part, said movable part having a resonance frequency and said magnetic circuit converting electric signal amplified by said amplifier to at least one of vibration and sound;
• and
• a detector for detecting the resonance frequency of said movable part and outputting it to said amplifier, said detector including said detection coil;
• wherein noise generated from an electric circuit at least including said amplifier and said detector is input to said amplifier.

An electro-mechanical/audio converting device comprising:

• an electro-mechanical/audio converter comprising a housing having a first opening end and a second opening end, a movable part including a magnetic circuit, a suspension for mounting said movable part on said housing near said first opening end for supporting said movable part so that it is movable, a vibrating plate mounted on said housing near said second opening end, said vibrating plate being disposed away from said movable part, a voice coil whose top end is connected to said vibrating plate and whose bottom part is inserted in a magnetic gap of said movable part, and a detection coil wound around said housing and disposed near said movable part, said detection coil generating excitation voltage by vibration of said movable part, wherein said movable part having at least one resonance frequency and said magnetic circuit converting electric signal into at least one of vibration and sound;
• an oscillator for generating an electric signal with frequency in a frequency band including a resonance frequency of said movable part in said electro-mechanical/audio converter and outputting it to said electro-mechanical/audio converter;
• a detector for detecting frequency of a predetermined output level of said electro-mechanical/audio converter as the resonance frequency, said detector including said detection coil;
• and
• a controller controlling said oscillator to generate the signal with the frequency of the frequency band including the resonance frequency of said electro-mechanical/audio converter and a signal with a frequency detected as the resonance frequency by said detector, using time division multiplexing.

An electro-mechanical/audio converting device comprising:

• an electro-mechanical/audio converter including a housing having a first opening end and a second opening end, a movable part including a magnetic circuit, a suspension for mounting said movable part on said housing near said first opening end for supporting said movable part so that it is movable, a vibrating plate mounted on said housing near said second opening end, said vibrating plate being disposed away from said movable part, a voice coil whose top end is connected to said vibrating plate and whose bottom part is inserted in a magnetic gap of said movable part, and a detection coil wound around said housing and disposed near said movable part, said detection coil generating excitation voltage by vibration of said movable part, wherein said movable part having at least one resonance frequency and said magnetic circuit for converting electric signal to at least one of vibration and sound;
• an oscillator for sweeping and oscillating electric signal with frequency in a frequency band including the resonance frequency of said electro-mechanical/audio converter and outputting said electric signal to said electro-mechanical/audio converter;
• a detector for detecting the output of said electro-mechanical/audio converter and outputting it as the output voltage, said detector having said detection coil;
• a voltage comparator notifying a controller of a resonance point of said electro-mechanical/audio converter when the output voltage from said detector exceeds a reference potential;
• and
• said controller for sending a frequency of said resonance point at the time of receiving notification to said oscillator.

An electro-mechanical/audio converter comprising:

• a housing having a first opening end and a second opening end;
• a movable part including a magnetic circuit;
• a suspension for mounting said movable part on said housing near said first opening end for supporting said movable part so that it is movable;
• a vibrating plate mounted on said housing near said second opening end, said vibrating plate being disposed away from said movable part;
• a voice coil whose top end is connected to said vibrating plate and whose bottom part is inserted in a magnetic gap of said movable part;
• and
• a detection coil disposed in a recess in said housing and near said movable part, said detection coil generating excitation voltage by vibration of said movable part.

An electro-mechanical/audio converting device comprising:

• an amplifier;
• an electro-mechanical/audio converter including a movable part having resonance frequency and at least having a magnetic circuit for converting electric signal amplified by said amplifier to at least one of vibration and sound, and a coil element;
• and
• a detector for detecting the resonance frequency of the movable part in said electro-mechanical/audio converter and outputting it to said amplifier,
• wherein noise generated from an electric circuit at least including said amplifier and said detector is input to said amplifier,
• said detector has a detection coil which is disposed near said movable part and generates excitation voltage by vibration of said movable part,
• and said detection coil is formed on a printed circuit board on which said electro-mechanical/audio converter is mounted.

An electro-mechanical/audio converting device comprising:

• an electro-mechanical/audio converter comprising a movable part having at least one resonance frequency and having a magnetic circuit for converting electric signal into at least one of vibration and sound, and a coil element;
• an oscillator for generating an electric signal with frequency in a frequency band including the resonance frequency of said movable part in said electro-mechanical/audio converter and outputting it to said electro-mechanical/audio converter;
• a detector for detecting frequency of a predetermined output level of said electro-mechanical/audio converter as the resonance frequency, said detector including a detection coil for generating excitation voltage according to vibration of said movable part, said detection coil disposed near said movable part;
• and
• a controller controlling said oscillator to generate the electric signal with frequency of the frequency band including resonance frequency of said electro-mechanical/audio converter and a signal with a frequency detected as the resonance frequency by said detector using time division multiplexing;
• wherein said detection coil is formed on a printed circuit board on which said electro-mechanical/audio converter is mounted.

An electro-mechanical/audio converting device

• comprising:
• an electro-mechanical/audio converter including a movable part having at least one resonance frequency and having a magnetic circuit for converting electric signal into at least one of vibration and sound, and a coil element;
• an oscillator for sweeping and oscillating an electric signal with frequency in a frequency band including the resonance frequency of said electro-mechanical/audio converter and outputting said electric signal to said electro-mechanical/audio converter;
• a detector for detecting the output of said electro-mechanical/audio converter and outputting it as the output voltage, said detector having a detection coil generating excitation voltage by vibration of said movable part, said detection coil disposed near said movable part;
• a voltage comparator notifying a controller of a resonance point of said electro-mechanical/audio converter when the output voltage from said detector exceeds a reference potential;
• and
• said controller for sending said frequency of said resonance point at the time of receiving notification to said oscillator;
• wherein said detection coil is formed on a printed circuit board on which said electro-mechanical/audio converter is mounted.