| 摘要 |
PURPOSE:To improve the lubrication failure of the sliding parts of the compressor of an air conditioner due to insufficient lubricant at the time of starting by a first holding frequency and to enhance reliability by holding the compressor at the first frequency imediately after starting for a predetermined time, and then holding it at a higher second holding frequency for a predetermined time. CONSTITUTION:The temperature of a substance to be cooled is detected by a temperature detector 9. A difference from its set temperature is detected by a detector 10, which sends a difference signal to a speed signal unit 8, which controls the number of the revolutions of a frequency variable type refrigerant compressor 1. That is, a refrigerant dissolution phenomenon in which refrigerant is dissolved in lubricant occurs during the stopping of the compressor 1. When the compressor 1 is started in this state, a large quantity of the lubricant in the compressor 1 is discharged together with the discharged refrigerant. Then, at the initial time of starting, the compressor 1 is driven at a first holding frequency f1 set to a lower frequency thereby to suppress the carrying amount of the lubricant. Then the compressor 1 is driven by a higher second holding frequency f2, and shifted to a warm-up operation of the starting. |
