US Patent 11912105 Heat pump for a vehicle

A heat pump includes a refrigerant loop. The refrigerant loop includes a first heat exchanger, a first region of a second heat exchanger, a third heat exchanger, a fourth heat exchanger, a compressor, a vapor generator, a first check valve, and a second check valve. The compressor includes a low-pressure inlet, a mid-pressure inlet, and an outlet. The vapor generator is positioned downstream of the outlet of the compressor and upstream of both the low-pressure inlet and the mid-pressure inlet. The first check valve is positioned immediately downstream of the third heat exchanger. The second check valve is positioned immediately downstream of the fourth heat exchanger.