VEHICLE THERMAL MANAGEMENT SYSTEM

Abstract

System (10), comprising: a coolant pump (14) configured to be mechanically driven by a power machine (12) and to send coolant to an inlet of the power machine (12); a first rotary valve (16) configured to receive coolant from an outlet of the engine (12) and to send coolant to a main cooler (20) and a heater core (26), wherein the first rotary valve (16) is adjustable to a flow position equal to zero in order to prevent coolant flow to the main cooler (20) and the heater core (26) and thereby increase a rate at which the engine (12) heats coolant flowing therein; a second rotary valve (18) configured to receive coolant from the first rotary valve (16) and to send coolant to an engine oil heat exchanger (28) and a transmission oil heat exchanger (30), wherein the second rotary valve (18) is adjustable to a flow position equal to zero to prevent coolant flow to the engine oil heat exchanger (28) and the transmission oil heat exchanger (30); and an engine inlet line extending from the coolant pump (14) to the engine inlet (12), wherein the second rotary valve (18) is configured to receive coolant from the engine inlet line; characterized by an auxiliary cooler (22) configured to: to receive coolant from the engine intake line; to send coolant to the second rotary valve (18); and to cool the coolant flowing through the auxiliary cooler (22).

Description

INTRODUCTION

[0001] The present invention relates to a vehicle thermal management system comprising a mechanically driven pump, one or more rotary valves, a bypass line enabling engine exhaust coolant to bypass one or more heat exchangers, or combinations thereof.

[0002] A generic system is essentially derived from DE 10 2015 109 728 A1.

[0003] Further details of the state of the art can be found in DE 10 2018 115 196 A1.

[0004] A vehicle thermal management system typically includes a coolant pump, a radiator, a condenser, a heater core, an engine oil heater (also referred to here as an engine oil heat exchanger), a transmission oil heater (also referred to here as a transmission oil heat exchanger), and valves. The coolant pump circulates coolant through the engine, the radiator, the heater core, the engine oil heater, and the transmission oil heater. The radiator cools the coolant flowing through it to prevent the engine from overheating. The radiator typically includes a fan that blows ambient air through it. The heater core warms cabin air by transferring heat from the coolant flowing through it to cabin air flowing through the heater core. The engine oil heater warms engine oil circulating through the engine.The transmission oil heater warms transmission oil that circulates through a transmission.

[0005] The condenser condenses gaseous refrigerant, which flows through coils inside the condenser, into liquid refrigerant by cooling the coolant. The main radiator fan blows air across the coils in the condenser to cool the coolant. The cooled refrigerant is used to cool the air inside the vehicle cabin. Valves are used to control the flow of coolant to the radiator, heater core, engine oil heater, and transmission oil heater. SUMMARY

[0006] According to the invention, a system is presented which is characterized by the features of claim 1.

[0007] In one aspect, the first rotary valve is adjustable to several non-zero flow positions to allow coolant to flow to the main cooler and the heater core at several non-zero flow rates that are different from each other.

[0008] In one aspect, the first rotary valve can be operated to control a rate of coolant flow to the main radiator independently of controlling a rate of coolant flow to the heater core, and to control the rate of coolant flow to the heater core independently of controlling the rate of coolant flow to the main radiator.

[0009] In one aspect, the system also includes a rotary valve control module configured to set the first and second rotary valves to zero in their flow positions when the temperature of the coolant flowing through the engine is lower than a first target temperature.

[0010] 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 the temperature of the oil flowing through the transmission oil heater is less than a second target temperature.

[0011] 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 the temperature of the oil flowing through the engine oil heater is less than a second target temperature.

[0012] In one aspect, if the engine coolant temperature is greater than or equal to the first target temperature and a cylinder wall temperature of the engine is greater than a second target temperature, the rotary valve control module is configured to set the first rotary valve to send coolant from the engine outlet to the main radiator and heater core, and to set the second rotary valve to send coolant from the engine inlet line to the engine oil heater and transmission oil heater.

[0013] In one aspect, the system further includes a bypass line configured to receive coolant from the first rotary valve and thereby allow coolant flowing through it to bypass the main radiator and heater core, and the first rotary valve is configured to send coolant to the engine inlet through the bypass line.

[0014] In one aspect, the first rotary valve is adjustable to several non-zero flow positions to allow a coolant to flow through the bypass line at multiple non-zero flow rates.

[0015] In one aspect, the rotary valve control module is configured to adjust the first rotary valve to send coolant to the engine inlet through the bypass line, while coolant is sent to the main radiator and 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 the engine speed is greater than a predetermined speed.

[0016] 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.

[0017] In one aspect, if 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 set the first rotary valve to send coolant from the engine outlet to the main radiator and heater core, and from the engine outlet to the engine inlet via the bypass line, and to set the second rotary valve to its flow position of zero to prevent coolant flow to the engine oil heater and the transmission oil heater.

[0018] Another system described here includes a coolant pump, a multi-position valve, and a bypass line. The coolant pump is configured to send coolant to an inlet of a power unit. The multi-position valve is configured to receive coolant from an outlet of the power unit 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, allowing coolant flowing through it to bypass the at least one heat exchanger. The multi-position valve is configured to send coolant to the power unit through the bypass line.

[0019] 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 extending from the multi-position valve to the engine inlet line.

[0020] In one aspect, at least one heat exchanger includes a radiator, and the engine inlet line extends from the radiator outlet to the coolant pump inlet.

[0021] Another system described here comprises a power unit, a coolant pump, a first rotary valve, and a second rotary valve. The coolant pump is mechanically driven by the power unit and is configured to send coolant to an inlet of the power unit. The coolant pump is always engaged with the power unit when assembled with it. The first rotary valve is configured to receive coolant from an outlet of the power unit and send coolant to a radiator and a heater core. The first rotary valve is adjustable to a flow-neutral position to prevent coolant flow to the radiator and heater core. The second rotary valve is configured to receive coolant from the first rotary valve and send coolant to a power unit oil heater and a transmission oil heater.The second rotary valve can be set to a flow position of zero to prevent coolant flow to the engine oil heater and the transmission oil heater.

[0022] In one aspect, the first rotary valve is adjustable in several non-zero flow positions to allow coolant to flow to the radiator and the heater core respectively with a first plurality of non-zero flow rates that are different from each other, and the second rotary valve is adjustable in several non-zero flow positions to allow coolant to flow to the engine oil heater and the transmission oil heater respectively with a second plurality of non-zero flow rates that are different from each other.

[0023] Further areas of application of the present invention will become apparent from the detailed description, the claims, and the drawings. The detailed description and the specific examples are intended for illustrative purposes only. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present invention will be more fully understood from the detailed description and the accompanying drawings, wherein: Fig. 1 a functional block diagram of an example of a power engine system comprising a main rotary valve and an oil rotary valve according to the present invention, wherein the main rotary valve and the auxiliary cooler are set to a zero flow condition; Fig. 2 is a flowchart that shows an example of a procedure for controlling the main rotary valve and the auxiliary cooler of Fig. 1 illustrated, according to the present invention. Fig. 3 a functional block diagram of the example of the power machine system of Fig. 1 is, wherein the main rotary valve and the auxiliary cooler are set in a gear oil heating flow condition; Fig. 4. A functional block diagram of an example of a power machine system. Fig. 1 is, wherein the main rotary valve and the auxiliary cooler are set in a cylinder migrating heating flow condition; Fig. 5 a functional block diagram of the example of the power machine system of Fig. 1 is, wherein the main rotary valve and the auxiliary cooler are set in a peak cooling flow condition; and Fig. 6. A functional block diagram of the example of the power machine system from Fig. 1 is where the main rotary valve and the auxiliary cooler are set in a heater request flow state.

[0025] Reference symbols can be reused in the drawings to identify similar and / or identical elements. DETAILED DESCRIPTION

[0026] Some vehicle thermal management systems incorporate an electric coolant pump. When the engine's cooling demand is high, such as when the engine speed is high and / or when the vehicle is towing a trailer, the electric coolant pump experiences a high power demand. The electrical system of some vehicles may not be configured to supply sufficient power to the electric coolant pump during periods of high cooling demand. Therefore, it may be necessary to redesign the electrical systems of these vehicles to accommodate an electric coolant pump, which can increase the cost of these vehicles.

[0027] Other vehicle thermal management systems employ a mechanical coolant pump (i.e., a coolant pump mechanically driven by the engine). The mechanical coolant pump is typically sized based on the vehicle's maximum possible cooling requirement. Thus, the mechanical coolant pump may be oversized for normal or low cooling demands, increasing the vehicle's cost. Furthermore, the valves used with mechanical coolant pumps are typically only capable of allowing or preventing coolant flow to heat exchangers, such as the radiator, heater core, engine oil heater, and transmission oil heater. The valves are typically unable to vary the rate of coolant flow to each of these components. Therefore, the ability of these systems to balance the heating and cooling needs of the engine, transmission, and vehicle cabin is limited.

[0028] A vehicle thermal management system according to the present invention comprises a mechanical coolant pump and / or a bypass line that allows the engine exhaust coolant to bypass all heat exchangers in the system (e.g., a radiator, a heater core, an engine oil heater, and a transmission oil heater). Additionally or alternatively, the system comprises one or more multi-position valves that control whether coolant flows to the heat exchangers and the bypass line, as well as the rate of coolant flow to the heat exchangers and the bypass line. In one example, the valves are operable to direct engine exhaust coolant or engine inlet coolant to the engine oil heater and the transmission oil heater. Additionally or alternatively, the system comprises an auxiliary cooler that further cools the engine inlet coolant on its way to the transmission oil heater.

[0029] The mechanical coolant pump is capable of meeting the cooling requirements of the engine and transmission without requiring a redesign of the vehicle's electrical system, thus saving costs. The bypass line allows flow to be diverted away from the heat exchangers based on peak flow limits and desired heat dissipation. The multi-position valves enable faster engine warm-up, fuel savings by limiting flow to the radiator, and a reduction in the size of the mechanical coolant pump by increasing flow to the radiator under peak flow conditions. The auxiliary cooler allows for more efficient transmission operation by reducing the viscosity of the transmission fluid.

[0030] Referring now to Fig. 1 comprises a power unit system 10, a power unit 12, a coolant pump 14, a main rotary valve (MRV) 16 (also referred to herein as the first rotary valve), an oil rotary valve (ORV) 18 (also referred to herein as the second rotary valve), a main radiator 20, an auxiliary radiator 22, a condenser 24, a heater core 26, a power unit oil heat exchanger (EOH) 28, and a transmission oil heat exchanger (TOH) 30. The power unit 12 comprises a power unit block 32, a cylinder head 34, an integrated exhaust manifold (IEM) 36, and a crankshaft 38. The power unit 12 has inlets 40 that receive coolant from the coolant pump 14 and outlets 42 that discharge the coolant to the MRV 16. The inlets 40 are arranged in the engine block 32 and the cylinder head 34. The outlets 42 are arranged in the engine block 32, the cylinder head 34 and the IEM 36.

[0031] The engine block 32 defines cylinders 44 with walls 46. The engine 12 further comprises pistons (not shown) arranged within the cylinders 44 and coupled to the crankshaft 38. Air and fuel are burned within the cylinders 44, causing the pistons to move back and forth within the cylinders 44. The reciprocal motion of the pistons causes the crankshaft 38 to rotate, generating drive torque. The cylinder head 34 accommodates intake valves 48 and exhaust valves 50. Air enters the cylinders 44 through an intake manifold (not shown) and the intake valves 48 when the intake valves 48 are open. Exhaust gas leaves the cylinders through the exhaust valves 50 and the internal exhaust manifold (IEM) 36 when the exhaust valves 50 are open.

[0032] The coolant pump 14 is mechanically driven by the engine 12. The coolant pump 14 is always engaged with the engine 12 when it is installed on the engine 12. The coolant pump 14 is coupled to the crankshaft 38. The coolant pump 14 circulates coolant through the engine 12 when the engine 12 is running. The output of the coolant pump 14 increases as the speed of the engine 12 increases. The coolant pump output decreases as the engine speed decreases.

[0033] The coolant pump 14 has an inlet 52 that receives coolant from the main radiator 20 and an outlet 54 that discharges coolant to the engine 12. The coolant pump 14 receives coolant from the main radiator 20 through a pump inlet line 56 that extends from the main radiator 20 to the inlet 52 of the coolant pump 14. The coolant pump 14 delivers coolant to the engine 12 through engine inlet lines 58 that extend from the outlet 54 of the coolant pump 14 to the inlets 40 of the engine 12.

[0034] The MRV 16 receives coolant from the outlets 42 of the engine 12 and discharges coolant to the pump inlet line 56, the main radiator 20, the heater core 26, and the ORV 18. The MRV 16 can be operated to control whether coolant flows to the pump inlet line 56, the main radiator 20, the heater core 26, and the ORV 18. For example, the MRV 16 can be set to a flow position of zero to prevent coolant flow to the main radiator 20 and the heater core 26. The MRV 16 can also be operated to control the rate at which coolant flows to the pump inlet line 52, the main radiator 20, the heater core 26, and the ORV 18. For example, the MRV 16 can be adjusted to several non-zero flow positions to allow the coolant to flow to the pump inlet line 56, the main cooler 20, the heater core 26 and the ORV 18 at several non-zero flow rates that are different from each other.

[0035] Furthermore, the MRV 16 can be operated to independently control the coolant flow to the pump inlet line 56, the main cooler 20, the heater core 26, and the ORV 18. For example, the MRV 16 can be operated to enable or prevent flow to the main cooler 20 independently of enabling or preventing flow to the heater core 26, and vice versa. In another example, the MRV 16 can be operated to adjust the rate at which coolant flows to the main cooler 20 independently of adjusting the rate at which coolant flows to the heater core 26, and vice versa.

[0036] The MRV 16 has an inlet 60, a first outlet 61, a second outlet 62, a third outlet 64, and a fourth outlet 66. The inlet 60 of the MRV 16 receives coolant from the outlets 42 of the engine 12 via engine outlet lines 68. The first outlet 61 of the MRV 16 discharges coolant to the ORV 18. The second outlet 62 of the MRV 16 discharges coolant to the pump inlet line 56 via a bypass line 70. The bypass line 70 allows the flowing coolant to bypass the main radiator 20, the heater core 26, and the ORV 18 (and thus bypass the EOH 28 and the TOH 30). The third outlet 64 of the MRV 16 discharges coolant to the main radiator 20. The fourth outlet 66 of the MRV 16 directs coolant to the heater core 26.The MRV 16 controls the rate at which coolant flows to the ORV 18, the pump inlet line 52, the main cooler 20 and the heater core 26 by adjusting the opening area of ​​the first outlet 61, the second outlet 62, the third outlet 64 and the fourth outlet 66 respectively.

[0037] When the coolant pressure in the engine outlet lines 68 rises sharply, some of the coolant in the engine outlet lines 68 flows to the pump inlet line 56 through an engine compensating line 67. An expansion tank 69 and an air separator 71 are arranged in the engine compensating line 67. The expansion tank 69 absorbs sudden pressure increases and quickly provides additional coolant during brief pressure drops. The air separator 71 removes air from the coolant flowing through the engine compensating line 67.

[0038] The ORV 18 receives engine outlet coolant from the MRV 16, receives engine inlet coolant from the auxiliary cooler 22, and discharges engine outlet or engine inlet coolant to the EOH 28 and the TOH 30. The ORV 18 can be operated to control whether coolant flows to the EOH 28 and the TOH 30, respectively. For example, the ORV 18 can be set to a flow position of zero to prevent coolant flow to the EOH 28 and the TOH 30. Furthermore, the ORV 18 can be operated to control the rate at which coolant flows to the EOH 28 and the TOH 30, respectively. For example, the ORV 18 can be set to several non-zero flow positions to allow coolant to flow to the EOH 28 and the TOH 30 at multiple non-zero flow rates that differ from one another.

[0039] Furthermore, the ORV 18 can be operated to independently control coolant flow to the EOH 28 and the TOH 30. For example, the ORV 18 can be operated to enable or prevent flow to the EOH 28 independently of enabling or preventing flow to the TOH 30, and vice versa. In another example, the ORV 18 can be operated to adjust the rate at which coolant flows to the EOH 28 independently of adjusting the rate at which coolant flows to the TOH 30, and vice versa.

[0040] The ORV 18 has a first inlet 72, a second inlet 74, a first outlet 76, and a second outlet 78. The inlet 72 of the ORV 18 receives engine outlet coolant from the second outlet 62 of the MRV 16. The second inlet 74 of the ORV 18 receives engine inlet coolant from the auxiliary cooler 22. The first outlet 76 of the ORV 18 discharges coolant to the EOH 28. The second outlet 78 of the ORV 18 discharges coolant to the TOH 30. The ORV 18 controls the rate at which coolant flows to the EOH 28 and the TOH 30 by adjusting the opening area of ​​the first outlet 76 and the second outlet 78, respectively. In various implementations, other types of multiposition valves may be used instead of the MRV 16 and / or the ORV 18.

[0041] The main cooler 20 and the auxiliary cooler 22 cool the flowing coolant. The main cooler 20 includes a fan 79 that blows ambient air through it. The main cooler 20 receives engine outlet coolant from the third outlet 64 of the MRV 16 and discharges engine inlet coolant to the coolant pump 14 through the pump inlet line 56. The auxiliary cooler 22 receives engine inlet coolant from the engine inlet lines 58 and discharges it to the second inlet 74 of the ORV 18. The engine inlet coolant discharged by the auxiliary cooler 22 is cooler than the engine inlet coolant received by the auxiliary cooler 22. The condenser 24 condenses gaseous refrigerant, which flows through coils in the condenser, into liquid refrigerant by cooling the coolant. The fan 79 of the main cooler 20 blows air past the coils in the condenser 24 to cool the coolant.The chilled refrigerant is used to cool the air inside the vehicle cabin.

[0042] When the coolant pressure in the main radiator 20 increases significantly, some of the coolant in the main radiator 20 flows to the engine coolant line 67 through a radiator coolant line 81. A shut-off valve 83 is located in the radiator coolant line 81. The shut-off valve 83 allows coolant flow through the radiator coolant line 81 from the main radiator 20 to the engine coolant line 67, while preventing coolant flow through the radiator coolant line 81 from the engine coolant line 67 to the main radiator 20.

[0043] The heater core 26 heats air in a vehicle cabin (not shown) by passing the air past a winding tube inside the heater core 26 through which engine outlet coolant flows. The heater core 26 cools the coolant flowing through this tube. The heater core 26 receives coolant from the fourth outlet 66 of the MRV 16 and discharges coolant to the pump inlet line 56 through a heater core outlet line 80. An auxiliary pump 82 is located in the heater core outlet line 80. The auxiliary pump 82 is an electric pump. The auxiliary pump 82 is used to circulate coolant through the heater core 26 to heat the vehicle cabin during automatic engine stops.

[0044] The EOH 28 heats flowing engine oil by extracting heat from the engine outlet coolant flowing through it and transferring this heat to the engine oil flowing through the EOH 28. The EOH 28 receives engine oil from the engine 12 via an engine oil line 84 and returns engine oil to the engine 12 via the same engine oil line 84. An engine oil pump 86 located in the engine oil line 84 circulates engine oil through the engine oil line 84 and the EOH 28.

[0045] The TOH 30 heats flowing transmission oil by extracting heat from the engine outlet coolant flowing through it and transferring this heat to the transmission oil. The TOH 30 receives transmission oil from a transmission (not shown) through a transmission oil line 88 and returns transmission oil to the transmission through the same transmission oil line 88. A transmission oil pump 90 located in the transmission oil line 88 circulates transmission oil through the transmission oil line 88 and the EOH 28.

[0046] The engine system 10 further comprises sensors and a rotary valve control module (RVCM) 92, which controls the MRV 16 and the ORV 18 based on inputs from the sensors. The sensors measure engine operating conditions and input signals to the RVCM 92 indicating the measured engine operating conditions. Signals output by the sensors are not shown to avoid confusion between the signals and the coolant lines. The sensors include an engine inlet coolant temperature sensor 94, IEM outlet coolant temperature sensors 96, an engine outlet coolant temperature sensor 98, an engine oil temperature sensor 100, a transmission oil temperature sensor 102, a main radiator outlet temperature sensor 104, a heater core outlet temperature sensor 106, and an auxiliary radiator outlet temperature sensor 108.

[0047] The engine inlet coolant temperature sensor 94 measures the temperature of the coolant flowing through the engine inlet lines 58. The IEM outlet coolant temperature sensors 96 measure the temperature of the coolant discharged through the IEM 36. The engine outlet coolant temperature sensor 98 measures the temperature of the coolant flowing through the engine outlet lines 68. The engine oil temperature sensor 100 measures the temperature of engine oil flowing through the engine oil line 84. The transmission oil temperature sensor 102 measures the temperature of transmission oil flowing through the transmission oil line 88. The main radiator outlet temperature sensor 104 measures the temperature of the coolant discharged through the main radiator 20. The heater core outlet temperature sensor 106 measures the temperature of the coolant discharged through the heater core 26, the EOH 28 and the TOH 30.The auxiliary cooler outlet temperature sensor 108 measures the temperature of the coolant discharged through the auxiliary cooler 22.

[0048] The RVCM 92 controls the MRV 16 and the ORV 18 by outputting control signals to the MRV 16 and the ORV 18, specifying a target flow state (or position) of the MRV 16 and the ORV 18, respectively. The control signals are not shown to avoid confusion between the control signals and the coolant lines. The RVCM 92 sets the position of the MRV 16 to regulate the coolant flow through the main radiator 20, the heater core 26, and the bypass line 70. The RVCM 92 regulates the coolant flow through the main radiator 20 and the bypass line 70 to control the temperature and pressure of the coolant flowing through the engine 12. The RVCM 92 regulates the coolant flow through the heater core 26 to control the temperature of the coolant flowing through it, thereby regulating the temperature of the air inside the vehicle cabin.The RVCM 92 receives the temperature of the coolant flowing through the engine 12 from the engine inlet coolant temperature sensor 94, the IEM outlet coolant temperature sensors 96 and / or the engine outlet coolant temperature sensor 98. The RVCM 92 receives the temperature of the coolant flowing through the heater core 26 from the heater core outlet temperature sensor 106.

[0049] The RVCM 92 adjusts the position of the ORV 18 to regulate coolant flow through the EOH 28 and the TOH 30 and to control whether the EOH 28 and the TOH 30 receive engine outlet coolant or engine inlet coolant. The RVCM 92 regulates coolant flow through the EOH 28 and controls whether the EOH 28 receives engine outlet coolant or engine inlet coolant to regulate the temperature of the coolant flowing through the EOH 28 and thereby regulate the engine oil temperature. The RVCM 92 regulates coolant flow through the TOH 30 and controls whether the TOH 30 receives engine outlet coolant or engine inlet coolant to regulate the temperature of the coolant flowing through the TOH 30 and thereby regulate the transmission oil temperature. The RVCM 92 receives the engine oil temperature from the engine oil temperature sensor 100. The RVCM 92 receives the transmission oil temperature from the transmission oil temperature sensor 102.

[0050] The RVCM 92 prioritizes the heating and cooling needs of the engine 12, the transmission, and the vehicle cabin when it regulates coolant flow through the main radiator 20, the auxiliary radiator 22, the heater core 26, the EOH 28, and the TOH 30. In one example, the RVCM 92 prevents coolant flow to the main radiator 20, the heater core 26, the EOH 28, and the TOH 30 to temporarily shut off the coolant pump 14, thereby warming up the engine 12 at a faster rate than would otherwise be possible. In another example, the RVCM 92 minimizes coolant flow through the main radiator 20 to maximize the efficiency of the engine 12 while still meeting its cooling requirements.

[0051] Referring now to Fig. 2 initiates a procedure to control the MRV 16 and the ORV 18 at 112. In the procedure description below, the RVCM 92 performs the steps of the procedure. However, other modules can perform the steps of the procedure. Additionally or alternatively, one or more steps of the procedure can be implemented separately by any module.

[0052] At 114, the RVCM 92 determines whether the engine 12 is in a cold-start or warm-up phase of operation. If the engine 12 is in a cold-start or warm-up phase, the procedure continues at 116. Otherwise, the procedure continues at 118. The RVCM 92 can determine that the engine 12 is in a cold-start or warm-up phase if the engine coolant temperature is lower than a first predetermined temperature (e.g., 40 degrees Celsius (°C)) while the engine 12 is being started. Additionally or alternatively, the RVCM 92 can determine that the engine 12 is in a cold-start or warm-up phase if the temperature of a catalyst in an exhaust system (not shown) of the engine 12 is lower than a second predetermined temperature (e.g., 300 °C) while the engine 12 is being started.Additionally or alternatively, the RVCM 92 can determine that the engine 12 is in a cold start or warm-up phase when the engine 12 is started after being switched off for an initial predetermined period (e.g., 12 hours). The RVCM 92 can determine when the engine 12 is started based on an input from an ignition switch.

[0053] The RVCM 92 can determine that the cold start or warm-up phase is complete when the engine coolant temperature is greater than or equal to the first predetermined temperature. Additionally or alternatively, the RVCM 92 can determine that the cold start or warm-up phase is complete when the catalyst temperature is greater than or equal to the second predetermined temperature. Additionally or alternatively, the RVCM 92 can determine that the cold start or warm-up phase is complete when the engine 12 has run for a second predetermined period (e.g., 10 minutes).

[0054] At position 116, the RVCM 92 sets the MRV 16 and the ORV 18 to their zero-flow states (or flow positions equal to zero). The MRV 16, in turn, prevents coolant flow to the main cooler 20 and the heater core 26, and the ORV 18 prevents coolant flow to the EOH 28 and the TOH 30. This temporarily shuts down the coolant pump 14, causing the coolant circulating through the power unit 12 to heat up at a faster rate. Fig. Figure 1 illustrates an example of the coolant flow through the power engine system 10 when the MRV 16 and the ORV 18 are set in their zero-flow states.

[0055] In the figures, coolant lines carrying engine inlet coolant are represented by dotted lines, coolant lines carrying engine outlet coolant are represented by solid lines, and coolant lines with no coolant flowing through them are represented by dashed-dotted lines. For example, in Fig. 1. Engine inlet coolant flows through the pump inlet line 56 and the engine inlet lines 58, engine outlet coolant flows through the engine outlet lines 68, and no coolant flows through the main radiator 20, the heater core 26, the EOH 28, or the TOH 30. Therefore, the pump inlet line 56 and the engine inlet lines 58 are represented by dotted lines, the engine outlet lines 68 by solid lines, and the lines in the main radiator 20, the heater core 26, the EOH 28, and the TOH 30 by dashed-dotted lines.

[0056] Referring again to Fig. 2. At 117, RVCM 92 determines whether the temperature of the cylinder walls 46 of the engine 12 is greater than or equal to a third target temperature. The third target temperature may be predetermined. If the cylinder wall temperature is greater than or equal to the third target temperature, the procedure continues at 128. Otherwise, the procedure continues at 138.

[0057] At step 118, RVCM 92 determines whether the transmission oil temperature is greater than or equal to a first target temperature (e.g., 80 °C). The first target temperature may be predefined. If the transmission oil temperature is greater than or equal to the first target temperature, the procedure continues at step 120. Otherwise, the procedure continues at step 122.

[0058] At position 122, the RVCM 92 sets the ORV 18 to a gearbox heating flow state (or position). The ORV 18, in turn, allows the engine outlet coolant received by the MRV 16 to flow to the TOH 30. In the gearbox heating flow state, the ORV 18 can maximize the opening area of ​​the second outlet 78 to heat the gearbox more quickly, or restrict the opening area of ​​the second outlet 78 to limit the flow to the TOH 30 and thereby heat the engine 12 more quickly. The RVCM 92 can restrict the flow to the TOH 30 by an amount based on the engine speed of the engine 12, with greater flow restriction at higher engine speeds and less flow restriction at lower engine speeds.

[0059] Fig. Figure 3 illustrates an example of the coolant flow through the power engine system 10 when the ORV 18 is set to the gearbox heating flow state. Fig. 3. The MRV 16 was adjusted from its zero-flow state to allow coolant flow to the heater core 26, and the ORV 18 was adjusted to prevent coolant flow to the EOH 28. When the ORV 18 is set to the gear heating flow state, the MRV 16 can remain in its zero-flow state and / or the ORV 18 can allow coolant flow to the EOH 28.

[0060] Referring again to Fig. 2. At step 120, RVCM 92 determines whether the engine oil temperature is greater than or equal to a second target temperature (e.g., a temperature within a range of 100 °C to 110 °C). The second target temperature may be predetermined. If the engine oil temperature is greater than or equal to the second target temperature, the procedure continues at step 124. Otherwise, the procedure continues at step 126.

[0061] At position 126, the RVCM 92 sets the ORV 18 to an engine heating flow state (or position). The ORV 18, in turn, allows the engine outlet coolant received by the MRV 16 to flow to the EOH 28. Coolant flows through the engine system 10 when the ORV 18 is set to the engine heating flow state corresponding to the one described in the diagram. Fig. The 3 shown may be similar or identical with the exception that, in the engine heating flow state, the ORV 18 allows the engine outlet coolant to flow to the EOH 28. When the ORV 18 is in the engine heating flow state, the MRV 16 can allow or prevent coolant flow to the heater core 26, and the ORV 18 can allow or prevent coolant flow to the TOH 30.

[0062] At 124, the RVCM 92 determines whether the temperature of the cylinder walls 46 of the engine 12 is greater than or equal to the third target temperature. The third target temperature may be predetermined. If the cylinder wall temperature is greater than or equal to the third target temperature, the procedure continues at 128. Otherwise, the procedure continues at 130.

[0063] The RVCM 92 can estimate the cylinder wall temperature based on engine operating conditions. These conditions can include the engine speed, engine inlet coolant temperature, engine outlet coolant temperature, the mass flow rate of the intake air drawn into the engine 12, and / or the engine runtime (or continuous operating period). The RVCM 92 can estimate the cylinder wall temperature based on a predetermined relationship between the engine operating conditions and the cylinder wall temperature. This predetermined relationship can be represented in a lookup table and / or an equation.

[0064] At 130, the RVCM 92 sets the MRV 16 and the ORV 18 to a cylinder wall heating flow state (or position). The MRV 16, in turn, allows coolant flow to the main cooler 20 and the heater core 26, and the ORV 18 prevents coolant flow to the EOH 28 and the TOH 30. Fig. Figure 4 illustrates an example of coolant flow through the engine system 10 when the ORV 18 is set to the cylinder wall heating flow condition. Fig. 4. The MRV 16 allows coolant flow to the heater core 26 and the bypass line 70. However, the MRV 16 can prevent coolant flow to the heater core 26 and / or the bypass line 70 if the MRV is set in the cylinder wall heating flow state.

[0065] Referring again to Fig. 2. At position 128, the RVCM 92 sets the MRV 16 and the ORV 18 in a peak cooling flow state (or position). The MRV 16, in turn, allows the coolant to flow to the main cooler 20 and the heater core 26, and the ORV 18 allows the engine inlet coolant to flow to the EOH 28 and the TOH 30. Fig. Figure 5 illustrates an example of coolant flow through the power engine system 10 when the MRV 16 and the ORV 18 are set to the peak coolant flow condition. Fig. 5 prevents the MRV 16 from allowing coolant flow through bypass line 70. However, the MRV 16 can allow coolant flow through bypass line 70 if the MRV is set to the peak coolant flow state.

[0066] Referring again to Fig. 2. At step 132, RVCM 92 determines whether the rotational speed of the engine 12 is less than a threshold speed (e.g., 3000 revolutions per minute). The threshold speed can be predefined. The threshold speed can be selected such that engine speeds greater than or equal to the threshold speed correspond to peak coolant flow conditions. Thus, the threshold speed can be selected based on the size of the coolant pump 14. If the engine speed is less than the threshold speed, the procedure continues at step 134. Otherwise, the procedure continues at step 136.

[0067] At position 134, the RVCM 92 sets the MRV 16 to a bypass-closed flow state (or position). The MRV 16, in turn, prevents coolant flow to the pump inlet line 56 through the bypass line 70. Preventing coolant flow through the bypass line 70 during normal (non-peak) coolant flow conditions allows the size of the coolant pump 14 to be reduced by ensuring that the coolant flows through the main radiator 20 at a sufficient rate. At position 136, the RVCM 92 sets the MRV 16 to a bypass-open flow state (or position). The MRV 16, in turn, allows coolant flow to the pump inlet line 56 through the bypass line 70, which releases or reduces the pressure in the engine outlet coolant lines during peak coolant flow conditions.

[0068] Fig. Figure 4 illustrates an example of coolant flow through the power engine system 10 when the MRV 16 is set to the bypass open flow state. As explained above, the Fig. Figure 6 also illustrated the coolant flow as the cylinder wall heating flow state. As shown in the flow diagram of Fig. 2. However, the bypass open flow state can also be implemented in conjunction with the transmission oil heating flow state or the engine oil heating flow state.

[0069] Referring again to Fig. At step 138, the RVCM 92 determines whether the heater core 26 is required (e.g., if heating the air inside the vehicle cabin is desired). The RVCM 92 can determine that the heater core 26 is required if the ambient temperature is lower than a predetermined temperature (e.g., 21°C). Additionally or alternatively, the RVCM 92 can determine that the heater core 26 is required based on user input from a user interface device, such as a touchscreen or control knob. For example, a passenger can select a desired cabin temperature via the user interface device, and the RVCM 92 can determine that the heater core 26 is required if the actual cabin temperature is lower than the desired cabin temperature. If the heater core 26 is required, the procedure continues at step 140. Otherwise, the procedure continues at step 142.

[0070] At 140, the RVCM 92 sets the MRV 16 to a heater-ON flow state (or position). The MRV 16 then allows coolant flow to the heater core 26. At 142, the RVCM 92 sets the MRV 16 to a heater-OFF flow state (or position). The MRV 16 then prevents coolant flow to the heater core 26. After 140 and 142, the procedure returns to 112. The procedure can be repeated if the ignition position is in an ON or START position.

[0071] Fig. Figure 6 illustrates an example of the coolant flow through the power engine system 10 when the MRV 16 is set to the heater-ON flow state. The in Fig. The coolant flow illustrated in section 6 is otherwise identical to that shown in Fig. The zero-flow state illustrated in section 1 is identical. As shown in the flow diagram of Fig.2. As is obvious, the heater-ON flow state can be implemented in conjunction with any of the other flow states explained above.

Claims

[1] System (10), comprising: a coolant pump (14) configured to be mechanically driven by a power machine (12) and to send coolant to an inlet of the power machine (12); a first rotary valve (16) configured to receive coolant from an outlet of the engine (12) and to send coolant to a main cooler (20) and a heater core (26), wherein the first rotary valve (16) is adjustable to a flow position equal to zero in order to prevent coolant flow to the main cooler (20) and the heater core (26) and thereby increase a rate at which the engine (12) heats coolant flowing therein; a second rotary valve (18) configured to receive coolant from the first rotary valve (16) and to send coolant to an engine oil heat exchanger (28) and a transmission oil heat exchanger (30), wherein the second rotary valve (18) is adjustable to a flow position equal to zero to prevent coolant flow to the engine oil heat exchanger (28) and the transmission oil heat exchanger (30); and an engine inlet line extending from the coolant pump (14) to the engine inlet (12), wherein the second rotary valve (18) is configured to receive coolant from the engine inlet line; characterized by an auxiliary cooler (22) configured to: to receive coolant from the engine intake line; to send coolant to the second rotary valve (18); and to cool the coolant flowing through the auxiliary cooler (22). [2] System (10) according to claim 1, further comprising a rotary valve control module (92) configured to set the first and second rotary valves (16, 18) to zero in their flow positions when the temperature of the coolant flowing through the engine (12) is lower than a first target temperature. [3] System (10) according to claim 2, wherein the rotary valve control module (92) is configured to adjust the second rotary valve (18) to send the coolant to the transmission oil heat exchanger (30) when the engine coolant temperature is greater than or equal to the first target temperature and the temperature of the oil flowing through the transmission oil heat exchanger (30) is less than a second target temperature. [4] System (10) according to claim 2, wherein, 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 (12) is greater than a second target temperature, the rotary valve control module (92) is configured to: to adjust the first rotary valve (16) to send coolant from the engine outlet (12) to the main radiator (20) and the heater core (26); and to adjust the second rotary valve (18) to send coolant from the engine inlet line to the engine oil heat exchanger (28) and the transmission oil heat exchanger (30). [5] System (10) according to claim 4, further comprising a bypass line (70) configured to receive coolant from the first rotary valve (16) and thereby allow coolant flowing bypass the main cooler (20) and the heater core (26), wherein the first rotary valve (16) is configured to send coolant to the inlet of the engine (12) through the bypass line (70). [6] System (10) according to claim 5, wherein the rotary valve control module (92) is configured to adjust the first rotary valve (16) to send coolant to the inlet of the engine (12) through the bypass line (70), while coolant is sent to the main radiator (20) and the heater core (26) 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 rotational speed of the engine (12) is greater than a predetermined rotational speed. [7] System (10) according to claim 6, wherein, 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 (92) is configured to: to adjust the first rotary valve (16) to send coolant from the engine outlet (12) to the main radiator (20) and the heater core (26) and from the engine outlet (12) to the engine inlet (12) through the bypass line (70); and to set the second rotary valve (18) to zero in its flow position in order to prevent coolant flow to the engine oil heat exchanger (28) and the transmission oil heat exchanger (30).

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