Air conditioning system for a vehicle

Claim 2

An air conditioning system for a vehicle, comprising an air supply blower (16), an air chilling device (24), an air heating device (26), speed sensing means (48) for determining the speed at which said blower (16) is operating and for generating a speed signal corresponding to said blower speed, power sensing means (48) for determining the power being consumed by said blower (16) and for generating a signal corresponding to said power consumption, temperature governing means, operatively associated with said air chilling device (24) and said air heating device (26), for controlling the heat flux imparted by said air chilling device (24) and said air heating device (26) to air supplied by said blower (16) to the interior of said vehicle, and control means (22), responsive to said speed signal and to said power signal, for operating said temperature governing means (28), comprising means for detecting non-programmed changes in blower speed and blower power consumption; and means for compensating for said non-programmed changes in blower speed and power consumption by changing the operating point of said temperature governing means (28).

Claim 3

An air conditioning system according to Claim 1, wherein said control means further comprises speed governing means (20) for controlling the speed at which said blower (16) is operating and means for compensating for said non-programmed blower speed and power consumption changes by changing the operating point of said speed governing means (20).

Claim 4

An air conditioning system according to Claim 1 or 2, wherein said air chilling device (24) comprises an evaporator core for receiving liquid refrigerant which is vaporised in said core.

Claim 5

An air conditioning system according to any preceding claim, wherein said air heating device (28) comprises a heater core for receiving engine coolant.

Claim 6

An air conditioning system according to any preceding claim, wherein said temperature governing means comprises a blend door (28) having the capability of directing the output of said blower (16) over said heater core (26), with said blend door (28) being operated by said control means (22).

Claim 7

An air conditioning system according to any preceding claim, wherein said air supply blower (16) comprises an electric motor (18) driving an aerodynamic element.

Claim 8

An air conditioning system according to Claim 6, wherein said power sensing means comprises means (48) for sensing the current and voltage applied to said blower motor (18) and means for converting said sensed current and voltage into a signal having a magnitude which is proportional to the power consumption of said blower motor (18).

Claim 9

An air conditioning system according to Claim 6 or 7, wherein said speed sensing means comprises means for sensing electromotive force pulses generated by said blower motor (18) and means for converting said pulses into a signal corresponding to the speed of said blower motor.

Claim 10

An air conditioning system according to Claim 8, wherein said means for converting said pulses into a signal corresponding to the speed of said blower motor comprises means for transforming said pulses into a square wave having a frequency which is equivalent to the frequency of said pulses; and means for counting the frequency of said resultant square wave.

Claim 11

An air conditioning system as claimed in Claim 5 or any claim appended thereto, wherein said heater core is positioned downstream from said evaporator core

Claim 12

An air conditioning system as claimed in Claim 5 or any claim appended thereto, wherein said temperature governing means further comprises means for controlling the flow of heat through said heater core and the flow of refrigerant through said evaporator.

Claim 15

An air conditioning system for a vehicle, comprising an air supply blower, driven by an electric motor, for bringing outside air into the interior of said vehicle, an evaporator core, a heater core positioned downstream from said evaporator core, speed sensing means for determining the speed at which said blower is operating and for generating a speed signal corresponding to said blower speed, speed governing means for controlling the speed at which said blower is operating, power sensing means for determining the power being consumed by said motor and for generating a signal corresponding to said power consumption, temperature governing means, operatively associated with said evaporator core and said heater core, for controlling the temperature of air supplied by said blower to the interior of said vehicle with said temperature governing means comprising a blend door having the capability of directing all or part of the output of said blower over said heater core; and control means, responsive to said speed and power consumption signals, for operating said temperature governing means and said speed governing means so as to maintain the temperature of conditioned air discharged into the cabin of said vehicle at a selected value, comprising means for detecting non-­programmed changes in blower speed and power consumption caused by changes in the mass flow rate of air passing through said air conditioning system; and means for compensating for said non-programmed speed and power consumption changes by determining new operating points for said temperature governing means and said speed governing means according to a hierarchical strategy, such that a calculated function of said power and speed signals will be regulated at a preselected value so as to maintain the mass flow rate and the temperature of air supplied by said blower to the cabin of said vehicle at selected values, but if such is not possible, maintaining the temperature of air discharged by said air conditioning system at said selected value.

Claim 16

An air conditioning system for a vehicle, comprising an air supply blower, driven by an electric motor, for bringing outside air into the interior of said vehicle, an evaporator core, a heater core positioned downstream from said evaporator core, speed sensing means for determining the speed at which said blower is operating and for generating a speed signal corresponding to said blower speed, speed governing means for controlling the speed at which said blower is operating, power sensing means for determining the power being consumed by said motor and for generating a signal corresponding to said power consumption, temperature governing means, operatively associated with said evaporator core and said heater core, for controlling the temperature of air supplied by said blower to the interior of said vehicle with said temperature governing means comprising a blend door having the capability of directing all or part of the output of said blower over said heater core; and control means, responsive to said speed and power consumption signals, for operating said temperature governing means and said speed governing means so as to maintain the temperature of conditioned air discharged into the cabin of said vehicle at a selected value, comprising means for detecting non-­programmed changes in blower speed and power consumption caused by changes in the mass flow rate of air passing through said air conditioning system; and means for compensating for said non-programmed speed and power consumption changes by determining new operating points for said temperature governing means and said speed governing means according to a hierarchical strategy, such that a calculated function of said power and speed signals will be regulated at a preselected value so as to maintain the mass flow rate and the temperature of air supplied by said blower to the cabin of said vehicle at selected values, but if such is not possible, maintaining the temperature of air discharged by said air conditioning system at said selected value.

Claim 17

An air conditioning system according to Claim 13, wherein said temperature governing means further comprises means for controlling the flow of engine coolant through said heater core and the flow of refrigerant through said evaporator.