AIR COMPRESSOR

PROBLEM TO BE SOLVED: To provide an air compressor capable of notifying users that piston rings must be replaced when they reach a wear limit for service. SOLUTION: The control circuit 9 preliminary stores the compression section 4's operating time Tm (reference data) for raising compressed air pressure in the tank 5 from a reference pressure Pr to an allowable maximum pressure Pm when the piston rings 45a and 45b reach their service limit. When operation is being monitored, the control circuit 9 detects by means of the pressure sensor 11 an operation time Ta (actually measured data) during which a pressure P in the tank 5 rises from the reference pressure Pr to the allowable maximum pressure Pm. An actually measured data (Ta) is compared with the reference data (Tm), and if the actually measured data Ta reaches the reference data Tm, the control circuit 9 controls the warning circuit 9a to notify that the piston rings have reached their replacement time in terms of visual or acoustic condition. COPYRIGHT: (C)2009,JPO&INPIT