LIGHT TRANSMITTING PART AND LIGHT RECEIVING PART OF EXTINCTION-TYP SM0KE SENSOR, AND THE EXTINCTION-TYPE SMOKE SENSOR

摘要

PURPOSE: To enable one operator to properly and speedily adjust the light emission quantity of the light transmitting part by providing the light transmitting part with a pulse voltage detecting means and a light emission quantity control means which controls the light emission quantity of an LED for light transmission according to the voltage of synchronizing pulses detected by the pulse voltage detecting means. ;CONSTITUTION: The pulse voltage detecting circuit 15 detects the voltage of the synchronizing pulses received from the light receiving part 20. Then the voltage of the synchronizing pulses is compared with a normal voltage as the voltage of synchronizing pulses in a monitor state and when the voltage of the synchronizing pulses is higher than the normal voltage, a control signal for increasing the current light emission quantity of the LED 11 for light transmission by a specific quantity is sent to a light emission quantity adjusting circuit 13, but when the voltage of the synchronizing pulses is lower than the normal voltage, on the other hand, a control signal for decreasing the current light emission quantity of the LED 11 for light transmission by a specific quantity is sent to the light emission quantity adjusting circuit 13. The light emission quantity adjusting circuit 13 controls the light emission quantity of the LED 11 for light transmission according to the voltage of the synchronizing pulses detected by the pulse voltage detecting circuit 15.;COPYRIGHT: (C)1996,JPO