Vehicle Heating, Ventilation and Air Conditioning System

Abstract

External air is drawn through a HVAC unit from an exterior air intake and recirculated air through a recirculation air inlet. An air intake management system includes first and second variable speed blowers and an air flow regulator. The air flow regulator defines a number of flow paths through which either exterior or recirculated air is drawn by either the first blower or the second blower. A valve arrangement regulates the flow of air through at least one of the flow paths. Control of the valves and the operating speeds of the blowers enables the amount and relative proportions of the external and recirculated air passing through the HVAC unit to be controlled. One air flow path for external air is permanently open and has an air mass flow sensor to monitor the flow of air.

Dependencies are inferred from the claim text.