Refrigeration – Automatic control – Of external fluid or means
Reexamination Certificate
2000-04-10
2001-09-25
Walberg, Teresa (Department: 3742)
Refrigeration
Automatic control
Of external fluid or means
Reexamination Certificate
active
06293115
ABSTRACT:
TECHNICAL FIELD
This invention relates to a vehicle air conditioning system having an inlet air mixing device, and more particularly to a control method for the inlet air mixing device that improves system efficiency and performance.
BACKGROUND OF THE INVENTION
A vehicle air conditioning system performs two primary functions: temperature regulation and dehumidification. These functions and the vehicle fuel economy can usually be enhanced by drawing at least a portion of the inlet air from the cabin of the vehicle after an initial cool-down period of operation because the introduction of cabin air generally reduces the enthalpy of the inlet air mixture. In most manually controlled systems, introducing cabin air into the inlet air-stream is achieved with a mechanical bleed device designed to maintain a given proportion of cabin air and outside air. In some manually controlled systems and most automatically controlled systems, inlet air mixing is achieved with an inlet air mixing device (such as controlled door in an inlet duct), with the inlet air mixture comprising predominantly outside air in a normal mode and predominantly cabin air in a recirculation mode. In the manually controlled versions, the operator selects either the normal or recirculation mode, while in the automatically controlled versions, the selection is performed by a system controller based on various input parameters such as the desired cabin temperature, the measured cabin temperature, and so on. In any event, it is commonly recommended that the usage of cabin air recirculation be limited in order to more effectively purge odors and smoke generated in the cabin, and in order to prevent intrusion of exhaust gases under certain conditions. Additionally, extended operation in the recirculation mode can tend to lower the relative humidity of the cabin air to an uncomfortable level.
SUMMARY OF THE INVENTION
The present invention is directed to an improved method for controlling inlet air mixing in a vehicle air conditioning system having an air inlet mixing device for admitting inlet air from outside and/or inside the vehicle cabin, wherein the mixing device is controlled under predefined operating conditions to reduce compressor power consumption and achieve performance improvements associated with cabin air recirculation while maintaining a predefined level of outside air flow in the inlet air mixture of the system. The overall air flow is determined by the speed of an inlet air blower motor, and the control of this invention is enabled under high thermal loading to adjust the inlet air mixing device as a function of the blower motor speed so that the predetermined level of outside air flow is preserved regardless of the blower motor speed.
REFERENCES:
patent: 4265597 (1981-05-01), Payne et al.
patent: 4537035 (1985-08-01), Stiles
patent: 4759269 (1988-07-01), Brown et al.
patent: 4892135 (1990-01-01), Sakurada et al.
patent: 4974664 (1990-12-01), Glennon et al.
patent: 5127576 (1992-07-01), Weatherhead et al.
patent: 5267451 (1993-12-01), Cleveland
patent: 5385030 (1995-01-01), Kitaagawa et al.
patent: 5511724 (1996-04-01), Freiberger et al.
patent: 5619862 (1997-04-01), Ruger et al.
patent: 5649429 (1997-07-01), Schreiber
patent: 6134895 (2000-10-01), Poloskey et al.
patent: 6151903 (2000-11-01), Hironaka
Forrest Wayne Oliver
Keen Elliott D.
Delphi Technologies Inc.
Griffin Patrick M.
Robinson Daniel
Walberg Teresa
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