Protection apparatus for sound signal converting device

摘要

An audio signal output from a tone generator 14 is fed into a coil 16 provided in a transducer for vibrating a sound board, so that a sound signal is generated by the vibration of the sound board. A microcomputer 30 obtains temperature values of the coil 16 measured by two different methods, and suspends supply of audio signals to the coil 16 or reduces the amount of audio signals supplied to the coil 16 if the difference between the two coil temperature values is outside a predetermined range. In a case as well where one of the two coil temperature values has risen excessively, the microcomputer 30 suspends supply of audio signals to the coil 16 or reduces the amount of audio signals supplied to the coil 16.

主权项

1. A protection apparatus for a sound signal converting device having a coil that converts an audio signal supplied to the coil to a sound signal, the protection apparatus protecting the sound signal converting device and comprising:
a level controller configured to supply an input audio signal to the coil in one of a first state where a level of the audio signal is maintained or a second state where supply of the input audio signal to the coil is suspended or the level of the input audio signal to the coil is decreased; a first temperature measurement device configured to measure a temperature of the coil as a first measured temperature; a second temperature measurement device configured to measure the temperature of the coil as a second measured temperature, independently of the first temperature measurement device; an unexpected condition controller configured to set the level controller to the second state when a difference between the first measured temperature and the second measured temperature is outside a predetermined range; and a temperature controller configured to:
keep the level controller at the first state when the difference between the first measured temperature and the second measured temperature falls within the predetermined range, while one measured temperature, among the first measured temperature and the second measured temperature, is lower than a first predetermined temperature; andswitch the level controller to the second state when the difference between the first measured temperature and the second measured temperature falls within the predetermined range, while the one measured temperature is equal to or higher than the first predetermined temperature.