Patent ID: 6360958
Filing Date: 2002-03-26
Classification: B60H

Abstract:
An air conditioning apparatus for a vehicle having an engine, said air conditioning apparatus comprising:a water circuit through which water heated by the engine circulates; a water pump driven by the engine, said water pump being disposed in said water circuit to circulate water in said water circuit; a heating heat exchanger, disposed in said water circuit, for heating air by performing heat exchange between water in said water circuit and air passing therethrough; a flow control valve which adjusts a flow amount of water flowing into said heating heat exchanger to adjust temperature of air blown from said heating heat exchanger, said flow control valve including a water bypass passage through which water bypasses said heating heat exchanger, and a pressure-response valve for adjusting an opening degree of said water bypass passage in accordance with pressure of water supplied from the engine by said water pump; and a control unit for controlling an opening degree of said flow control valve to become a target opening degree so that the flow amount of water flowing into said heating heat exchanger is controlled, wherein said control unit corrects the target opening degree of said flow control valve in a direction for reducing variation in the flow amount of hot water flowing into said heating heat exchanger due to variation in a rotation speed of the engine; said control unit includes correction determining means for determining whether or not a correction of the opening degree of said flow control valve is necessary; and said control unit performs the correction of the target opening degree of said flow control valve based on the mean rotation speed of the engine relative to a predetermined time, when the rotation speed of the engine decreases when the correction determining means determines that the correction of the opening degree of said flow control valve is necessary.