A CASCADE HEAT PUMP

摘要

PURPOSE: A cascade heat pump device is provided to smoothly circulate the heat of a first refrigerant and a second refrigerant by installing a thermal storage tank instead of a refrigerant heat exchanger. CONSTITUTION: A cascade heat pump device comprises a first refrigerant cycle(10), a second refrigerant cycle(20), and a heat storage tank(25). The first refrigerant cycle uses a first refrigerant. The second refrigerant cycle uses a second refrigerant heat exchanging with the first refrigerant. The heat storage tank stores heat from one of the first and second refrigerants and supplies the stored heat to the other refrigerant.