Vehicular air-conditioning system

A vehicular air-conditioning system provided with:

• an air-conditioning case forming an air passage through which air flows toward an inside of a vehicle interior,
• a cooling use heat exchanger provided inside said air-conditioning case and cooling air,
• a heating use heat exchanger provided inside said air-conditioning case and heating air cooled at said cooling use heat exchanger,
• first and second cool air bypass passages making cool air from said cooling use heat exchanger bypass said heating use heat exchanger,
• a first air mix chamber formed inside said air-conditioning case and mixing cool air from said first cool air bypass passage and warm air from said heating use heat exchanger,
• a first air mix means provided inside said air-conditioning case for adjusting a ratio of flow rates of cool air passing through said first cool air bypass passage and warm air passing through said heating use heat exchanger mixed at said first air mix chamber,
• a second air mix chamber formed inside said air-conditioning case at an air flow downstream side of said heating use heat exchanger for mixing cool air from said second cool air bypass passage and warm air from said heating use heat exchanger,
• a second air mix means provided inside said air-conditioning case for adjusting a ratio of flow rates of cool air passing through said second cool air bypass passage and warm air from said heating use heat exchanger mixed at said second air mix chamber,
• front seat vent openings blowing air-conditioning air mixed at said first air mix chamber toward the front seat side in the vehicle interior, and
• rear seat vent openings blowing air-conditioning air mixed at said second air mix chamber toward the rear seat side in the vehicle interior,
• in said vehicular air-conditioning system,
• said heating use heat exchanger being arranged so that an air inflow surface and air outflow surface extend in a vehicle up-down direction,
• said second cool air bypass passage being comprised of a tunnel-shaped passage having a cool air inlet for introducing cool air from part of an air outflow surface of said cooling use heat exchanger and a cool air outlet for guiding cool air introduced from said cool air inlet out to said second air mix chamber, and
• said first and second cool air bypass passages both being formed at one of a top region or bottom region of said heating use heat exchanger.