| 摘要 |
PROBLEM TO BE SOLVED: To protect an inverter type compressor by varying the opening of an expansion valve immediately upon increase of the operating frequency of the compressor and varying the opening of the expansion valve with a time lag upon decrease of the operating frequency. SOLUTION: A main control section 16 controls the operating conditions, e.g. the operating frequency, of an inverter type compressor 11. An opening control section 17 calculates an appropriate opening of an expansion valve depending on the operating conditions of the inverter type compressor 11 and controls the opening of a motor expansion valve 14. The main control section 16 comprises a frequency detection means 16a and a frequency holding means 16b. The frequency detection means 16a detects the operating frequency of the inverter type compressor 11 and the frequency holding means 16b holds the operating frequency detected by the frequency detection means 16a. The opening control section 17 comprises an opening delay means 17a for delaying the opening time of the motor expansion valve 14. Since the inverter type compressor 11 is protected against application of a heavy load, service life thereof can be prolonged. |
