| 摘要 |
PURPOSE:To carry out the cooling operation with an evaporator under the full refrigerant state and improve the cooling ability of the evaporator by detecting the level of an accumulator and controlling the opening degree of an expansion valve so that the evaporator is filled with a liquid refrigerant. CONSTITUTION:When the operation is started with an expansion valve 4 being full-opened and the air temperature is lowered, the refrigerant amount in an accumulator 8 is increased, and a float 44 is raised to increase the resistance value. Thus, an electric current corresponding to the resistance value is inputted as a level signal of the liquid refrigerant to an amplifier 21, where the level signal is compared with the st temperature corresponding signal of a controller. When the level signal is smaller or in accord, the refrigerant amount within the evaporator 5 is less or optimal, so that the amplifier 21 continues the full- opening of the valve 4 without operating a stepping motor M, but when the level signal is larger, the refrigerant is excessive. Thus, when the liquid refrigerant is stored in a determined amount within the accumulator 8, the evaporator 5 is started to operate in the state filled with the refrigerant, and the air is cooled by the whole evaporator to improve the heat exchanging efficiency. |
