| 摘要 |
<p>PURPOSE: To suppress the frosting of an external heat exchanger during heating operation at low temperature of outside air, shorten defrosting time, improve heating capacity and the reliability and the safety operation of a compressor and to make energy-saving operation possible without impairing amenity in a cabin by making two kinds of fluids flow separately in the external heat exchanger. CONSTITUTION: An aluminum pipe (or copper pipe) 17 is inserted in laminated fins 16. At the heating time, low-temperature low-pressure refrigerant, and cooling liquid receiving heat by cooling a heating component such as a driving motor, flow separately while meandering and intersecting in the aluminum pipe (or copper pipe) 17 from the lower part of an external heat exchanger 14 toward the upper part. It is desirable to determine the flowing way of each fluid by frosting state, a defrosting state and the setting of pass balance for maintaining air-conditioning and heating performance to the maximum. As a result, the low-temperature low-pressure refrigerant and cooling liquid can be heat-exchanged through metal with high heat conductivity as a medium, so that heat exchange efficiency can be kept high.</p> |
