Internal combustion engine total cooling control system

An engine cooling system comprising:

• an engine;
• a radiator assembly including a radiator and a fan driven by a variable speed electric fan motor;
• a radiator temperature sensor to detect a temperature indicative of a temperature at said radiator,
• a coolant circulation circuit interconnecting said engine and said radiator for circulating coolant;
• a by-pass circuit connected to said coolant circulation circuit so that coolant may by-pass said radiator;
• a heater circuit connected to the coolant circulation circuit;
• a heater core in said heater circuit;
• a valve in said heater circuit to control flow of coolant through said heater core;
• an electrically powered variable speed coolant pump disposed in said coolant circulation circuit to pump coolant through said coolant circulation circuit, and
• control valve structure constructed and arranged to control a mass flow of coolant through said radiator;
• a engine temperature sensor to detect a temperature of engine coolant;
• and
• a controller operatively connected with said coolant pump, said electric fan motor, said control valve structure, said heater valve, said engine temperature sensor, and said radiator temperature sensor to (1) selectively control said heater valve and said control valve structure, (2) control speed of said coolant pump based on signals received from said engine temperature sensor, and (3) control speed of said electric fan motor based on a signal received from radiator temperature sensor, thereby controlling an operating temperature of said engine to approach a target operating temperature, without monitoring actual speed or load of said engine.

A method of controlling an operating temperature of an engine, the engine having a cooling system including a radiator assembly including a radiator and a fan driven by an electric fan motor;

• a coolant circulation circuit interconnecting the engine and the radiator for circulating coolant;
• a by-pass circuit connected to the coolant circulation circuit so that coolant may by-pass the radiator;
• an electrically powered variable speed coolant pump disposed in the coolant circulation circuit to pump coolant through the coolant circulation circuit;
• control valve structure constructed and arranged to control mass flow of coolant through the radiator;
• an engine temperature sensor to detect a temperature of engine coolant;
• a radiator temperature sensor to detect a temperature indicative of a temperature at said radiator;
• and controller operatively connected the electric fan motor, the coolant pump, the control valve structure, the engine temperature sensor, and the radiator temperature sensor, the method including:
• determining the temperature of coolant at the engine and comparing the coolant temperature with a target engine coolant temperature,
• based on a difference between said coolant temperature and said target engine coolant temperature, operating said control valve structure and controlling the coolant pump to control a mass flow rate of coolant though the radiator, thereby adjusting the operating temperature of the engine,
• determining an actual temperature of air exiting the radiator or coolant at an outlet of the radiator and comparing said actual temperature to a maximum target temperature;
• and
• based on a difference between said actual temperature and said maximum target temperature, controlling a speed of the electric fan motor to improve thermal performance of the radiator.

A method of controlling an operating temperature of an engine, the engine having a cooling system including a radiator assembly including a radiator and a fan driven by an electric fan motor;

• a coolant circulation circuit interconnecting the engine and the radiator for circulating coolant;
• a by-pass circuit connected to the coolant circulation circuit so that coolant may by-pass the radiator;
• an electrically powered variable speed coolant pump disposed in the coolant circulation circuit to pump coolant through the coolant circulation circuit;
• control valve structure constructed and arranged to control mass flow of coolant through the radiator;
• an engine temperature sensor to detect a temperature of engine coolant;
• a radiator temperature sensor to detect one of a temperature of air exiting the radiator and a temperature of coolant at an outlet of the radiator;
• and controller operatively connected the electric fan motor, the coolant pump, the control valve structure, the engine temperature sensor, and the radiator temperature sensor, the method including:
• determining a rise in coolant temperature in the engine and comparing the temperature rise with a target rise in engine coolant temperature,
• based on a difference between said rise in coolant temperature and said target rise in engine coolant temperature, operating said control valve structure and controlling the coolant pump to control a mass flow rate of coolant though the radiator, thereby adjusting the operating temperature of the engine,
• determining an actual temperature of air exiting the radiator or a temperature of coolant at an outlet of the radiator and comparing said actual temperature to a maximum target temperature;
• and
• based on a difference between said actual temperature and said maximum target temperature, controlling a speed of the electric fan motor to improve thermal performance of the radiator.