HEAT PUMP

The present invention relates to a heat pump comprising: a compressor; an air conditioning and heating transfer valve; an indoor heat exchanger; a first expansion valve; and an outdoor heat exchanger. The outdoor heat exchanger comprises: a front-heat heat exchange portion connected with the first expansion valve through a coolant passage, and exchanging heat with outdoor air; a rear-heat heat exchange portion connected to the air conditioning and heating transfer valve through the coolant passage, and exchanging heat with the outdoor air, exchanged heat with the front-heat heat exchange portion, by being located in a rear circuit of the front-heat heat exchange portion in a moving direction of the outdoor air; a connecting passage which connects the front-heat heat exchange portion and the rear-heat heat exchange portion; and a second expansion valve installed in the connecting passage. The present invention can improve an air conditioning performance and a heating performance with the minimum number of components and a simple structure. 본 발명은 압축기와, 냉난방절환밸브와, 실내열교환기와, 제1팽창밸브와 실외열교환기를 포함하고, 실외열교환기는 제1팽창밸브와 냉매 유로로 연결되고 실외 공기와 열교환되는 전열 열교환부와; 냉난방절환밸브와 냉매 유로로 연결되고 실외 공기의 유동방향으로 전열 열교환부의 후류에 위치하여 전열 열교환부와 열교환된 실외 공기가 열교환되는 후열 열교환부와, 전열 열교환부와 후열 열교환부를 연결하는 연결유로와; 연결유로에 설치된 제2팽창밸브를 포함하여, 최소한의 부품수와 간단한 구조로 냉방 성능 및 난방 성능 모두를 향상시킬 수 있는 이점이 있다.