INTRODUCTION

The information provided in this section is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.

The present disclosure relates to a vehicle thermal management system including a mechanically driven pump, one or more rotary valves, a bypass line allowing engine outlet coolant to bypass one or more heat exchangers, or combinations thereof.

A vehicle thermal management system typically includes a coolant pump, a radiator, a condenser, a heater core, an engine oil heater, a transmission oil heater, and valves. The coolant pump circulates coolant through an engine, the radiator, the heater core, the engine oil heater, and the transmission oil heater. The radiator cools coolant flowing therethrough to prevent the engine from overheating. The radiator typically includes a fan that blows ambient air through the radiator. The heater core heats air from a vehicle cabin by transfer heat from coolant flowing through the heater core to cabin air flowing through the heater core. The engine oil heater heats engine oil that is circulated through the engine. The transmission oil heater heats transmission oil that is circulated through a transmission.

The condenser condenses gaseous refrigerant flowing coils in the condenser into liquid refrigerant by cooling the refrigerant. The fan of the main radiator blows air past the coils in the condenser to cool the refrigerant. The cooled refrigerant is used to cool air within the vehicle cabin. The valves are used to control coolant flow to the radiator, the heater core, the engine oil heater, and the transmission oil heater.

SUMMARY

A first example of a system according to the present disclosure includes a coolant pump and a first rotary valve. The coolant pump is configured to be mechanically driven by an engine and to send coolant to an inlet of the engine. The first rotary valve is configured to receive coolant from an outlet of the engine and to send coolant to a first radiator and a heater core. The first rotary valve is adjustable to a zero flow position to prevent coolant flow to the first radiator and the heater core and thereby increase a rate at which the engine warms coolant flowing therethrough.

In one aspect, the first rotary valve is adjustable to a plurality of nonzero flow positions to allow coolant to flow to each of the first radiator and the heater core at a plurality of nonzero flow rates that are different than one another.

In one aspect, the first rotary valve is operable to regulate a rate of coolant flow to the first radiator independent of regulating a rate of coolant flow to the heater core, and to regulate the rate of coolant flow to the heater core independent of regulating the rate of coolant flow to the first radiator.

In one aspect, the system further includes a second rotary valve configured to receive coolant from the first rotary valve and to send coolant to an engine oil heater and a transmission oil heater. The second rotary valve is adjustable to a zero flow position to prevent coolant flow to the engine oil heater and the transmission oil heater.

In one aspect, the system further includes an engine inlet line extending from the coolant pump to the inlet of the engine, and the second rotary valve is configured to receive coolant from the engine inlet line.

In one aspect, the system further includes a second radiator configured to receive coolant from the engine inlet line, send coolant to the second rotary valve, and cool coolant flowing through the second radiator.

In one aspect, the system further includes a rotary valve control module configured to adjust the first and second rotary valves to their zero flow positions when a temperature of coolant flowing through the engine is less than a first target temperature.

In one aspect, the rotary valve control module is configured to adjust the second rotary valve to send coolant to the transmission oil heater when the engine coolant temperature is greater than or equal to the first target temperature and a temperature of oil flowing through the transmission oil heater is less than a second target temperature.

In one aspect, the rotary valve control module is configured to adjust the second rotary valve to send coolant to the engine oil heater when the engine coolant temperature is greater than or equal to the first target temperature and a temperature of oil flowing through the engine oil heater is less than a second target temperature.

In one aspect, when the engine coolant temperature is greater than or equal to the first target temperature and a temperature of a cylinder wall of the engine is greater than a second target temperature, the rotary valve control module is configured to adjust the first rotary valve to send coolant from the outlet of the engine to the first radiator and the heater core, and to adjust the second rotary valve to send coolant from the engine inlet line to the engine oil heater and the transmission oil heater.

In one aspect, the system further includes a bypass line configured to receive coolant from the first rotary valve and to allow coolant flowing therethrough to bypass the first radiator and the heater core, and the first rotary valve is configured to send coolant to the inlet of the engine through the bypass line.

In one aspect, the first rotary valve is adjustable to a plurality of nonzero flow positions to allow coolant to flow through the bypass line at a plurality of nonzero flow rates.

In one aspect, the rotary valve control module is configured to adjust the first rotary valve to send coolant to the inlet of the engine through the bypass line while sending coolant to the first radiator and the heater core when the engine coolant temperature is greater than or equal to the first target temperature, the cylinder wall temperature is greater than the second target temperature, and a speed of the engine is greater than a predetermined speed.

In one aspect, the rotary valve control module is configured to adjust the first rotary valve to prevent coolant flow to the engine through the bypass line when the engine coolant temperature is greater than or equal to the first target temperature, the cylinder wall temperature is greater than the second target temperature, and the engine speed is less than or equal to the predetermined speed.

In one aspect, when the engine coolant temperature is greater than or equal to the first target temperature and the cylinder wall temperature is less than or equal to the second target temperature, the rotary valve control module is configured to adjust the first rotary valve to send coolant from the outlet of the engine to the first radiator and the heater core and from the outlet of the engine to the inlet of the engine through the bypass line, and to adjust the second rotary valve to its zero flow position to prevent coolant flow to the engine oil heater and the transmission oil heater.

A second example of a system according to the present disclosure includes a coolant pump, a multi-position valve, and a bypass line. The coolant pump is configured to send coolant to an inlet of an engine. The multi-position valve is configured to receive coolant from an outlet of the engine and to send coolant to at least one heat exchanger. The multi-position valve is adjustable to a zero flow position to prevent coolant flow to the at least one heat exchanger. The bypass line is configured to receive coolant from the multi-position valve and to allow coolant flowing therethrough to bypass the at least one heat exchanger. The multi-position valve is configured send coolant to the engine through the bypass line.

In one aspect, the system further includes an engine inlet line extending from an outlet of the at least one heat exchanger to an inlet of the coolant pump, and the bypass line extends from the multi-position valve to the engine inlet line.

In one aspect, the at least one heat exchanger includes a radiator, and the engine inlet line extends from the outlet of the radiator to the inlet of the coolant pump.

A third example of a system according to the present disclosure includes an engine, a coolant pump, a first rotary valve, and a second rotary valve. The coolant pump is mechanically driven by the engine and is configured to send coolant to an inlet of the engine. The coolant pump is always engaged with the engine when the coolant pump is assembled to the engine. The first rotary valve is configured to receive coolant from an outlet of the engine and to send coolant to a radiator and a heater core. The first rotary valve is adjustable to a zero flow position to prevent coolant flow to the radiator and the heater core. The second rotary valve is configured to receive coolant from the first rotary valve and to send coolant to an engine oil heater and a transmission oil heater. The second rotary valve is adjustable to a zero flow position to prevent coolant flow to the engine oil heater and the transmission oil heater.

In one aspect, the first rotary valve is adjustable to a plurality of nonzero flow positions to allow coolant to flow to each of the radiator and the heater core at a first plurality of nonzero flow rates that are different than one another, and the second rotary valve is adjustable to a plurality of nonzero flow positions to allow coolant to flow to each of the engine oil heater and the transmission oil heater at a second plurality of nonzero flow rates that are different than one another.

Further areas of applicability of the present disclosure will become apparent from the detailed description, the claims and the drawings. The detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the disclosure.

