发明名称 |
PROTECTIVE CIRCUIT FOR ELECTROACOUSTIC TRANSDUCER |
摘要 |
<p>The output signal of an l-f (low-frequency) power amplifier is supplied to an electroacoustic transducer, through an inductive element for preventing parasitic oscillation, to cause the inductive element to generate a magnetic flux whose density depends on the output current signal of the power amplifier while a current according to the magnitude of the output voltage signal of the power amplifier is supplied to the current input terminals of a Hall-effect element disposed in the magnetic field induced by the inductive element, so that a dc voltage according to the output power of the l-f power amplifier is taken out of the output terminals of the Hall-effect element. When the voltage exceeds a predetermined level for a time determined by a circuit having a time constant in accordance with the time constant of temperature rise in the voice coil of the transducer, the l-f signal supplied to the electroacoustic transducer is attenuated by a signal attenuating circuit so that the transducer is prevented from being damaged.</p> |
申请公布号 |
CA1080126(A) |
申请公布日期 |
1980.06.24 |
申请号 |
CA19770287535 |
申请日期 |
1977.09.26 |
申请人 |
HITACHI, LTD. |
发明人 |
BABA, TATSUO;OHMURA, YOSHITO;FUKUSHIMA, HIROSHI;FUKUMA, HIDEO |
分类号 |
H03F1/52;H02H1/00;H03F1/42;H04R3/00;(IPC1-7):04R3/00 |
主分类号 |
H03F1/52 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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