Gas mask air supply regulating method - using motor current and voltage to detect air flow variation and for power regulation

摘要

A fan motor (1) together with fan blades and housing surrounding them form a sensor. The current (I) running through the motor (1) and the voltage (U1) operating over the motor detect the variations of the air flow, the power supplied to the fan motor (1) being then regulated on the basis of the current and voltage. An electronic regulation circuit (R11, 3, OP1, 4, 5) including operation switches (6A,3B), is set to maintain the air amount supplied to the gas mask essentially constant by regulating the power of the fan motor (1).