Patent ID: 7055590

Claim:
An air conditioning apparatus for a vehicle, comprising: a coolant cycle including, in order, a compressor for compressing a coolant, an outdoor-side coolant heat exchanger for exchanging heat of the coolant compressed by the compressor with ambient air, an expansion unit for expanding the coolant after heat exchange at the outdoor-side coolant heat exchanger, an indoor-side coolant heat exchanger for exchanging heat of the coolant expanded by the expansion unit with air conditioning wind supplied into a vehicle cabin, and a piping that returns the cycle to the compressor, wherein the coolant heat exchangers and the expansion unit are in communication with each other; a water-coolant heat exchanger arranged between the compressor and the outdoor-side coolant heat exchanger to exchange heat of the coolant discharged from the compressor with cooling water of a power source for driving the vehicle; a flow-path switching unit for selectively introducing the coolant discharged from the compressor to either a flow path for the water-coolant heat exchanger or another flow path to avoid the water-coolant heat exchanger; a detection unit for detecting a temperature of the cooling water flowing into the power source; a control unit for controlling the flow-path switching unit such that the coolant discharged from the compressor either is introduced to the water-coolant heat exchanger when the temperature of the cooling water is equal to or less than a predetermined temperature or avoids the water-coolant heat exchanger when the temperature of the cooling water is more than the predetermined temperature; a heating expansion unit arranged between the water-coolant heat exchanger and the outdoor-side coolant heat exchanger to expand the coolant supplied to the outdoor-side coolant heat exchanger; and an expansion switching unit for selectively introducing the coolant supplied into the outdoor-side coolant heat exchanger to either a flow path for the heating expansion unit or another flow path to avoid the heating expansion unit.