| 摘要 |
PURPOSE:To enhance the efficiency of a main motor of a centrifugal refrigerating machine by adjusting an amount of coolant in proportion to an output of the main motor. CONSTITUTION:Cooling of a main motor 3 is performed with coolant which is collected in the bottom of a condensor 1 and led to the main motor 3 via a cooling pipe 5 by the difference of a pressure in the condensor 1 and a pressure in the main motor 3. because the calorific value in the main motor 3 is proportional to the output of the main motor 3, cooling of the main motor 3 is conducted by adjusting the amount of coolant 6 through closing/opening of a motor valve 7, which is installed midway on the cooling pipe 5, operating in proportion to a load current of the motor 3 with input of the load current. With such a construction, feeding of the optimum amount of coolant can be secured even at partial load operation of the main motor 3, so that efficiency of the main motor is improved. |
