COOLING SYSTEM WITH VARIABLE COOLANT FLOW PATHS FOR THE EXHAUST GAS RECIRCULATION SYSTEM

Abstract

Motor (102) for a vehicle (100), comprising: an exhaust gas recirculation system (106, EGR system) configured to receive exhaust gas generated by the engine (102) and to recirculate the exhaust gas back to the engine (102), wherein the EGR system (106) comprises an EGR component (108, 110); a cooling system (126) configured for selective cooling of the engine (102) and the EGR component (108, 110), comprising the cooling system (126): a coolant pump (128); and a piping system (130) with a plurality of flow branches arranged for circulating coolant pumped through the cooling system (126) by the coolant pump (128), wherein the plurality of flow branches includes an engine branch defining an engine flow channel through which the coolant flows to cool an EGR branch (162) defining an EGR flow channel through which the coolant flows to cool the EGR component (108, 110), and a supply branch (220) defining a supply flow channel; wherein the cooling system (126) has a first operating configuration in which the EGR flow channel is configured to receive a coolant flow from the engine flow channel; and wherein the cooling system (126) has a second operating configuration in which the EGR flow channel is configured to receive a coolant flow instead of the engine flow channel from the supply flow channel, further comprising an EGR inlet valve (226) configured to move between a first position and a second position; wherein the EGR inlet valve (226) is configured to change a flow characteristic through the inlet flow channel when the EGR inlet valve (226) moves between the first position and the second position; wherein the EGR inlet valve (226) is in the first position in the first operating configuration; wherein the EGR inlet valve (226) is in the second position in the second operating configuration; wherein the first position of the EGR inlet valve (226) is a closed position; and wherein the EGR inlet valve (226) in the closed position is configured to prevent coolant from flowing from the supply flow channel to the EGR flow channel.

Description

[0001] The present disclosure relates to an engine for a vehicle having a cooling system with variable coolant flow paths for an exhaust gas recirculation system.

[0002] An internal combustion engine typically consists of an engine block with at least one cylinder. Each cylinder houses a piston, which is connected to a crankshaft via a connecting rod and, in conjunction with a cylinder head, defines a combustion chamber. A mixture of air and fuel is introduced into the combustion chamber and cyclically ignited, producing rapidly expanding gases that drive linear movements of the piston, which in turn are converted by the connecting rod into rotation of the crankshaft.

[0003] Some engines may be configured with an exhaust gas recirculation (EGR) system. EGR systems generally reduce the amount of one or more substances (e.g., NOx) emitted into the atmosphere with the engine exhaust. In typical EGR systems, a portion of the exhaust gas is recirculated to an intake side of the engine and combusted with the air-fuel mixture in the engine cylinders to reduce the amount of NOx emitted into the atmosphere.

[0004] Vehicle EGR devices may include a cooling system to cool one or more components. However, the operation of the EGR cooling system can negatively impact other vehicle systems. For example, the EGR cooling system can affect engine operating temperatures, which can cause the engine to operate inefficiently, reduce fuel efficiency, or produce other undesirable effects.

[0005] DE 10 2015 119 304 A1 describes an internal combustion engine cooling system comprising: a first coolant circulation passage passing through an internal combustion engine; a second coolant circulation passage bypassing the internal combustion engine; an electric water pump; a connecting passage connecting the first coolant circulation passage and the second coolant circulation passage; an electromagnetic valve disposed in the connecting passage to change a flow rate of a coolant passing through the internal combustion engine and flowing from the first coolant circulation passage to the second coolant circulation passage; an EGR cooler, a heater core, and an exhaust heat collecting device disposed in the second coolant circulation passage.and a control unit, wherein the closing of the electromagnetic valve is prohibited if there is an actuation request of the EGR cooler, the heater core, and the exhaust heat collecting device when there is a valve closing request of the electromagnetic valve;

[0006] DE 10 2008 042 660 A1 describes a liquid-cooled internal combustion engine with a coolant circuit, comprising a coolant jacket integrated in the cylinder head, a supply line for supplying the coolant jacket with coolant, a discharge line for discharging the coolant and a coolant-operated oil cooler.

[0007] DE 101 46 313 A1 describes a cooling circuit of a liquid-cooled internal combustion engine of a motor vehicle with a main circuit leading through an internal combustion engine, a coolant pump, a mixing valve (thermostat), a radiator and further with at least one secondary circuit which contains a heating heat exchanger and / or an oil-water heat exchanger and / or an exhaust gas recirculation cooling system, wherein the flow direction in the secondary circuit is reversible by means of a pump or a valve.

[0008] DE 10 2015 109 728 A1 describes an engine thermal management system for a vehicle having an exhaust system and an engine with an integrated exhaust manifold, and a method for controlling the same. The engine thermal management system includes a coolant pump, an engine water jacket, and a controller. The engine water jacket discharges coolant from an IEM coolant outlet cast directly into the integrated exhaust manifold.The coolant flowing through the engine water jacket and expelled from the IEM coolant outlet is in heat exchange relationship with heated exhaust gas flowing through the exhaust system via an engine cylinder head and an exhaust bulkhead to thereby remove heat therefrom, resulting in heated coolant being expelled from the IEM coolant outlet and selectively routed by the controller to a heater core, an engine oil heat exchanger, a transmission heat exchanger, or a radiator.

[0009] Accordingly, it may be considered an object to provide an EGR cooling system that effectively cools the components of the EGR system without adversely affecting the operation of the engine and / or other vehicle systems. Other objects, desirable features, and characteristics will become apparent from the following summary and detailed description and the appended claims, taken in conjunction with the accompanying drawings and technical context.

[0010] According to the invention, an internal combustion engine for a vehicle is disclosed that includes an exhaust gas recirculation (EGR) system configured to receive exhaust gas produced by the engine and circulate the exhaust gas back to the engine. The EGR system includes an EGR component. A cooling system is provided to selectively cool the engine and the EGR component. The cooling system includes a coolant pump and a piping system having a plurality of flow branches arranged to circulate coolant pumped by the coolant pump through the cooling system. The plurality of flow branches includes an engine branch, an EGR branch, and a supply branch. The engine branch defines an engine flow passage through which coolant flows to cool the engine. The EGR branch defines an EGR flow passage through which coolant flows to cool the EGR component. The supply branch defines a supply flow passage.The cooling system has a first operating configuration in which the EGR flow passage is configured to receive coolant flow from the engine flow passage. The cooling system has a second operating configuration in which the EGR flow passage is configured to receive coolant flow from the supply flow passage instead of from the engine flow passage.The engine further includes an EGR inlet valve configured to move between a first position and a second position, wherein the EGR inlet valve is configured to change a flow characteristic through the supply flow passage when the EGR inlet valve moves between the first position and the second position, wherein the EGR inlet valve is in the first position in the first operating configuration, wherein the EGR inlet valve is in the second position in the second operating configuration, wherein the first position of the EGR inlet valve is a closed position, and wherein the EGR inlet valve is configured in the closed position to prevent coolant from flowing from the supply flow passage to the EGR flow passage. Fig. 1 is a side view of a vehicle with a cooling system; Fig. 2 shows a schematic view of a cooling system of the vehicle of Fig. 1; Fig. 3 is a schematic view of the cooling system of Fig. 2, shown in a first operating configuration; Fig. 4 is a schematic view of the cooling system of Fig. 2, which is shown in a second operating configuration; and Fig. Figure 5 is a schematic view of the cooling system of Fig. 2.

[0011] Some embodiments may include a motor vehicle 100 as shown in Fig. 1. As shown in the Fig. 1 and Fig. 2, the vehicle 100 may include an engine 102, here in the form of an internal combustion engine (ICE). In some embodiments, the engine 102 may be a diesel engine; however, it should be understood that the engine 102 may be of other types without departing from the scope of the present disclosure.

[0012] As in Fig. 2, the engine 102 may include an engine block 103 and a cylinder head 105. The engine block 103 may define at least one cylinder with a piston disposed therein. The piston may include a linkage used to rotate a crankshaft. The cylinder head 105 is attached to the engine block 103 for closing the cylinders such that the cylinder head 105 and the engine block 103 together define a combustion chamber. An air-fuel mixture is introduced into the combustion chamber and ignited, resulting in hot, expanding combustion gases that cause the piston to move back and forth within the cylinder. As a result of combustion, exhaust gas may be produced by the engine 102.

[0013] The vehicle 100 may additionally include an exhaust system 104. The exhaust system 104 may include one or more elements (e.g., exhaust pipes, conduits, flow channels, etc.) for directing the flow of exhaust gases produced by the engine 102.

[0014] In some embodiments, a turbocharger component 107 may be included as part of the exhaust system 104. The turbocharger component 107 may be of a known type and may include a turbine section and a compressor section. The turbine section may be rotated by the exhaust gas flowing through the exhaust system 104, causing the compressor section to rotate. The compressor section, in turn, compresses the air flowing into the combustion chambers of the engine 102. An intercooler or other similar device may also be included for cooling the temperature of the compressed air flowing out of the compressor section and toward the engine 102.

[0015] Additionally, vehicle 100 may include a throttle valve 109. Throttle valve 109 may be generally referred to as an air management valve. In some embodiments, throttle valve 109 may regulate the intake air of engine 102 and / or control exhaust gas recirculation. In some embodiments, the position of throttle valve 109 may also be sensed and / or controlled to influence the amount of fuel injected into the combustion chambers of engine 102.

[0016] Additionally, the exhaust system 104 of the vehicle 100 may also include one or more aftertreatment devices configured to treat the exhaust gases, for example, to reduce the amount of substances (e.g., NOx, soot, etc.) contained in the exhaust stream. Furthermore, the exhaust system 104 may include components (e.g., a tailpipe, etc.) that direct the exhaust stream into the atmosphere. Other components, such as an exhaust gas recirculation (EGR) system 106 ( Fig. 2) may be included that recirculate the exhaust flow back to an intake side of the engine 102. The EGR system 106 may recirculate exhaust gas to the engine 102 to reduce NOx emissions of the vehicle 100, for example.

[0017] The EGR system 106 may be a known EGR system and may include one or more EGR components, such as a short-distance or high-pressure EGR component (HP EGR component) 108 and a long-distance or low-pressure EGR component (LP EGR component) 110. The HP EGR component 108 may receive exhaust gas directly from an exhaust manifold and direct the exhaust gas back to an intake manifold of the engine 102. The exhaust flow through the HP EGR component 108 may be controlled by an exhaust gas recirculation valve 112. The LP EGR component 110 may receive an exhaust flow from an aftertreatment device, such as a diesel particulate filter (not shown). The LP EGR component 110 may direct this exhaust gas back to the intake system of the engine 102.

[0018] Furthermore, the vehicle 100 may include at least one lubrication system 114, 119. For example, the vehicle 100 may include an engine lubrication system 114 and a transmission lubrication system 119.

[0019] The engine lubrication system 114 may include an engine oil pump 116 and an oil circuit 117. The oil circuit 117 is configured to circulate oil pumped by the engine oil pump 116 through the engine lubrication system 114. While the oil circuit 117 is partially shown, it should be understood that the oil circuit 117 circulates oil through the engine 102 to lubricate one or more moving parts of the engine 102 (e.g., parts connected to the drive shaft, etc.). The engine lubrication system 114 may further include an engine oil heater 118. The engine oil heater 118 may be configured to selectively heat oil located within or flowing into the engine block 103. For example, the applied heat may reduce the viscosity of the oil pumped by the engine oil pump 116 to make the engine 102 easier to start in cold weather conditions.

[0020] Additionally, the transmission lubrication system 119 may include a fluid pump 120 and a fluid circuit 121. The fluid circuit 121 is configured to circulate transmission fluid pumped by the fluid pump 120 through a transmission assembly of the vehicle 100. It is understood that the transmission assembly may include one or more rows of meshing / intermeshing gears, a plurality of shafts that may support the gears, etc. The transmission assembly may transmit torque and power from a drive shaft of the engine 102 to wheels of the vehicle 100. The transmitted torque may also be subject to various gear ratios applied by the transmission assembly in different transmission modes. Also, the fluid circuit 121 is partially shown, but it is understood that the fluid circuit 121 may circulate transmission fluid through the transmission assembly to lubricate the gears, shafts, etc.The transmission lubrication system 119 may further include a transmission fluid heater 122. The transmission fluid heater 122 may be configured to selectively heat the transmission fluid located within or flowing into the transmission assembly. The applied heat may, for example, reduce the viscosity of the transmission fluid, thereby increasing the efficiency of the transmission assembly.

[0021] The vehicle 100 may further include a cooling system 126, which, according to embodiments, is described in more detail in Fig. 2. In general, the cooling system 126 may be configured for selectively cooling (i.e., removing heat) from the engine 102, the EGR system 106, and / or other components and systems of the vehicle 100. The cooling system 126 may also be configured for selectively heating (i.e., providing heat) to some components of the vehicle 100. For example, in some embodiments, the cooling system 126 may receive heat from the engine 102 and / or the EGR system 106 to cool those components, and the cooling system 126 may also transfer heat to the engine oil heater 118, the transmission fluid heater (e.g., a transmission oil heater) 122, and / or other components of the vehicle 100.

[0022] As in Fig. 2, the cooling system 126 may generally include a coolant pump 128 and a piping system 130. The coolant pump 128 may pump a coolant through the piping system 130. The piping system 130 may include a plurality of flow branches (i.e., flow lines, tubes, etc.) arranged to circulate coolant pumped by the coolant pump 128 through the cooling system 126.

[0023] The cooling system 126 may further include a radiator 132. The radiator 132 may be a heat exchanger having a plurality of spaced-apart fins exposed to the atmosphere. The piping system 130 may be fluidly connected to the radiator 132, as discussed in detail below. Therefore, in some operating configurations of the cooling system 126, coolant may flow from the coolant pump 128, collect heat from the engine 103, the EGR system 106, and / or other components, and the heated coolant may flow to the radiator 132 such that heat from the coolant is exposed to the atmosphere and therefore cooled again. The cold coolant may then flow back to the coolant pump 128.

[0024] Furthermore, the cooling system 126 may further include a heater 124. The heater 124 may be a heat exchanger having a plurality of spaced fins arranged in a duct fluidly connected to the interior of a passenger compartment 134 of the vehicle 100. A fan may selectively blow onto the heater 124, and the blown air may exchange heat with the coolant flowing through the heater 124. The piping system 130 may be fluidly connected to the heater 124, as described in more detail below.Therefore, in some operating configurations of the cooling system 126, coolant may flow from the coolant pump 128, collect heat from the engine 103, the EGR system 106, and / or other components, and the heated coolant may flow to the heater 124 so that this heat from the coolant transfers to the air blown over the heater 124 to heat the interior of the passenger compartment 134 of the vehicle 100. The coolant may exit the heater 124 and flow back to the coolant pump 128.

[0025] As will be discussed, the cooling system 126 can transition between a variety of different operating configurations (i.e., different configurations). In the different operating configurations, coolant can flow through the piping system 130 through different paths. In some embodiments, the cooling system 126 can transition from one operating configuration to another to change the path of the coolant through the cooling system 126. Additionally, in some embodiments, the operating configuration of the cooling system 126 can change to change a flow rate of the coolant through a particular component (e.g., the engine 102 and / or the EGR system 106). For example, in some embodiments, the cooling system 126 can have a first operating configuration in which the EGR system 106 is cooled by coolant, at least some of which flows generally away from the engine 102.In this example, the cooling system 126 may also have a second operating configuration in which the EGR system 106 is cooled by coolant that has bypassed the engine 102. In some embodiments, the cooling system 126 may be in the first operating configuration when the engine 102 is warmed up (i.e., above a predetermined threshold temperature). Alternatively, in this example, the cooling system 126 may be in the second operating configuration when the engine 102 is cold (i.e., below a predetermined threshold temperature). Thus, for example, the cooling system 126 may be in the second operating configuration during start-up and initial warm-up of the engine 102 in cold weather conditions. Thus, coolant flow through the engine 102 may be reduced and / or prevented, allowing the engine 102 to warm up in a relatively short time.Coolant bypassing the engine 102 may also flow through the EGR system 106 to cool the EGR system 106. These and other features of the cooling system 106 are explained in more detail below with reference to exemplary embodiments of the present disclosure.

[0026] The operating configurations of the cooling system 126 may be selected (ie, may be selectable). In some embodiments, the operating configuration may be automatically selected by an electronic control system operating according to programmed control logic. In other embodiments, the operating configuration may be automatically changed using mechanical, hydraulic, and / or temperature-dependent components without the use of a computerized control system.

[0027] Referring to Fig. 2, the cooling system 126 is discussed in more detail.

[0028] The piping system 130 of the cooling system 126 is described as having a plurality of flow branches. Each flow branch may include one or more hollow tubes, pipes, conduits, flow elements, or other components that define fluid channels through the cooling system 126. These components may be constructed from any suitable material and may be rigid or flexible. The flow branches may also include one or more flow control devices configured to regulate flow characteristics (e.g., a mass or volumetric flow rate) through the respective flow passage of the flow branch.

[0029] For example, at least one flow branch may include a valve for changing the flow through the respective branch. Additionally or alternatively, at least one flow branch may include an element with an opening that restricts the flow in a predetermined manner.

[0030] The piping system 130 may additionally include one or more nodes. The nodes may provide a fluid connection between two different flow branches. Some nodes may receive a flow input from two or more flow branches and output a combined flow to another branch. Other nodes may receive a flow input from one flow branch and output the flow to two or more branches.

[0031] In the embodiment of Fig. 2, the cooling system 126 may, for example, include a common flow branch 138. The common flow branch 138 may extend from a pump outlet 136. Thus, the flow channel of the common flow branch 138 may receive coolant pumped out of the coolant pump 128.

[0032] As in Fig. 2, the piping system 130 may include a first engine flow branch 140 and a second engine flow branch 142. The first engine flow branch 140 may extend from the common flow branch 138 and may provide coolant flow to the engine block 103. The second engine flow branch 140 may extend from the common flow branch 138 and may provide coolant flow to the cylinder head 105. In some embodiments, the first and second engine flow branches 140, 142 may extend parallel from the common flow branch 138 (i.e., coolant flow from the common branch 138 may be split between the first and second flow branches in some situations). Accordingly, the respective flow channels defined by the first and second engine flow branches 140, 142 may directly receive coolant flow from the common flow branch 138.

[0033] The first engine flow branch 140 may include an intake manifold 144 that distributes coolant to the engine block 103. The first engine flow branch 140 may also include an outlet portion 146. Coolant may flow from the intake manifold 144 and into the outlet portion 146 so that the coolant can absorb (and cool) heat from the engine block 103. The outlet portion 146, in some embodiments, may also include a block valve 148. The block valve 148 may be movable between an open position and a closed position. In the open position, the block valve 148 may allow flow through the first engine flow branch 140.

[0034] The second engine flow path 142 may include an intake manifold 150 that distributes coolant to the cylinder head 105. The second engine flow path 142 may also include an exhaust manifold 152 and, further downstream, an outlet section 154. Coolant may flow from the intake manifold 150 over the cylinder head 105 and into the exhaust manifold 152, allowing the coolant to absorb heat from (and cool) the cylinder head 105.

[0035] The piping system 130 may further include a first hub 156. In some embodiments, this first hub 156 may be a three-way connection with two inlets and one outlet. The first hub 156 may fluidly connect the outlet portion 146 of the first engine flow branch 140 and the outlet portion 154 of the second engine flow branch 142. Thus, the first hub 156 may combine the flow from both the first and second engine flow branches 140, 142 and output the combined flow to other downstream components toward an engine coolant flow control valve 158.

[0036] The engine coolant flow control valve 158 receives a combined flow of the first and second engine flow branches 140, 142. In some embodiments, the engine coolant flow control valve 158 may have at least one ON position that allows coolant flow and an OFF position that prevents coolant flow through one or both engine flow branches 140, 142. In some embodiments, the valve 158 may be adjustable between multiple ON positions, and the flow rate through the engine coolant flow control valve 158 (e.g., the mass flow rate through the engine coolant flow control valve 158) may be different in each position.

[0037] Additionally, the piping system 130 may include a second hub 160. In some embodiments, the second hub 160 may be a three-way connection with one inlet and two outlets. The second hub 160 may receive flow from the engine coolant flow control valve 158 and may split that flow between an EGR branch 162 and a first supply 164. The first supply 164 may provide flow to a first port 166 of a variable valve 168, which is discussed in more detail below.

[0038] The EGR branch 162 may be divided into various sub-branches. Some of these sub-branches may be fluidically connected in series (the flow from one sub-branch is received by another sub-branch). Others may be fluidically connected in parallel (the input flow may be divided among multiple sub-branches).

[0039] For example, the EGR branch 162 may include a first sub-branch 170 that provides coolant to the HP EGR component 108 for cooling the HP EGR component 108. The EGR branch 162 may also include a second sub-branch 172 that provides coolant to the LP EGR component 110 for cooling the LP EGR component 110. The EGR branch 162 may also include a third sub-branch 174 that supplies coolant to and cools the throttle valve 109, and a fourth sub-branch 176 that supplies coolant to and cools the turbocharger component 107. The first, second, third, and fourth sub-branches 170, 172, 174, 176 may be connected in fluid communication in parallel, as shown in Fig. 2. In other words, the input flow from node 160 may be split between the first, second, third, and fourth sub-branch in some situations. Additionally, a first intermediate sub-branch 178 may be in fluid communication with HP EGR 108 and valve 112 to allow coolant to flow from HP EGR 108 to valve 112. Similarly, a second intermediate sub-branch 180 may be in fluid communication with valve 112 and second sub-branch 172 to allow coolant to flow from valve 112 to LP EGR component 110. Thus, HP EGR component 108, valve 112, and LP EGR component 110 may be fluidly connected in series in some embodiments.

[0040] Additionally, an EGR outlet 181 may be fluidly connected downstream of the LP EGR component 110 and extend to a common outlet member 182. The common outlet member 182 may also receive flow 183 from the outlet of the throttle body 109 and / or the turbocharger component 107. The outlet member 182 may extend from these components to a third node 184. In some embodiments, the third node 184 may be a three-way connection with one inlet and two outlets. The third node 184 may receive flow from the outlet member 182 and may split that flow between a core feed branch 185 and a second feed 186 to a second port 188 of the variable valve 168.

[0041] Furthermore, the piping system 130 may include a direct flow branch 190. The direct flow branch 190 may extend away from the common flow branch 138 and may extend to a third port 191 of the variable valve 168. Accordingly, flow may be directed through the direct flow branch 190 from the common flow branch 138 to the third port 191 and may bypass the engine 102 and the EGR system 106 (here, the HP EGR 108, the valve 180, and the LP EGR 110), as well as the throttle valve 109 and the turbocharger component 107.

[0042] The variable valve 168 may be a rotary valve in some embodiments. Additionally, the variable valve 168 may include a first outlet port 192, a second outlet port 194, and a third outlet port 196. The first outlet port 192 may be configured to receive flow from the second supply 186 and / or the direct flow branch 190 depending on the position of the variable valve 168. Additionally, flow from the first supply 164 may be input to the first port 166 and output via the second outlet port 194 and / or the third outlet port 196 depending on the position of the variable valve 168.

[0043] Additionally, core feed branch 185 may bypass variable valve 168 and extend to heater 124. In some embodiments, core feed branch 185 may extend from node 184 to a fourth node 198. Node 198 may split the flow from core feed branch 185 between core path 200 and core bypass 202. In some embodiments, flow from core path 200 and core bypass 202 may be introduced into a second coolant pump 204.

[0044] The second coolant pump 204 can pump this coolant to a return branch 206 of the piping system 130. The return branch 206 can allow coolant to flow back to the coolant pump 128 for recirculation through the cooling system 126.

[0045] The piping system 130 may further include an engine oil heater branch 208 and a transmission fluid heater branch 210. The flow to these branches may be provided jointly from the first outlet port 192. Downstream of the port 192, the branches 208, 210 may be fluidly connected in parallel, meaning that the coolant flow is split between the two branches 208, 210. The output from these branches 208, 210 may merge back into the return branch 206, as in the embodiment of Fig. 2 shown.

[0046] Furthermore, the cooler 132 may be in fluid communication with the second outlet port 194. The outlet of the cooler 132 may be fluidly connected to the return branch 206, as shown in Fig. 2 shown.

[0047] In addition, the third outlet port 196 can be directly and fluidically connected to the return branch 206 via a flow branch 212.

[0048] The cooling system 126 may further include a surge tank 214. The surge tank 214 may receive a flow introduced by the radiator 132, and the surge tank 214 may discharge coolant back to the return branch 206.

[0049] Furthermore, the cooling system 126 may include a plurality of sensors 216. The sensors 216 may be used to monitor one or more conditions. For example, the sensors 216 may detect temperature and / or flow conditions of the coolant at one or more locations of the cooling system 126. There may be any suitable number of sensors 216. The sensors 216 may be located throughout the cooling system 126. In some embodiments, one or more sensors 216 may be thermometers for detecting the temperature of the coolant at the particular location of the cooling system 126. Furthermore, in some embodiments, one or more sensors 216 may be flow sensors for detecting flow characteristics (e.g., mass flow rate) of the coolant at the particular location of the cooling system 126.

[0050] The cooling system 126 further includes an EGR supply branch 220. The EGR supply branch 220 includes a tube having an inlet end 222 and an outlet end 224. The EGR supply branch 220 defines a supply flow channel and a fluid path through which coolant flows from the inlet end 222 to the outlet end 224.

[0051] The inlet end 222 may be in fluid communication with the common flow branch 138. In some embodiments, the inlet end 222 may be connected to the common flow branch 138 between the second engine flow branch 142 and the direct flow branch.

[0052] The outlet end 224 may be in fluid communication with the EGR branch 162. In some embodiments, the outlet end 224 may be connected to the EGR branch 162 at a location upstream of the first, second, third, and fourth sub-branches 170, 172, 174, 176. Thus, the outlet end 224 may be connected to the EGR branch 162 at a location upstream of the EGR system 106 (i.e., the HP EGR component 108, the LP EGR component 110), as well as the throttle body 109 and the turbocharger component 107. Accordingly, in some situations, flow from the EGR supply branch 220 may be received in the sub-branches 170, 172, 174, 176, the EGR system 106, the throttle valve 109, and / or the turbocharger component 107.

[0053] It is understood that the EGR supply branch 220, the first engine flow branch 140, the second engine flow branch 142 and the direct flow branch 190 may extend in parallel from the common flow branch 138, as in the embodiment of Fig. 2. Accordingly, these branches 220, 140, 142, 190 may each receive coolant flow directly from the common flow branch 138, and flow from the coolant pump 128 may, in some situations, be split between the first engine flow branch 140, the second engine flow branch 142, the EGR supply branch 220, and the direct flow branch 190.

[0054] Additionally, in some situations, the EGR supply branch 220 may provide coolant flow directly from the common flow branch 138 to the first sub-branch 170 of the EGR branch 162 for supplying coolant to the HP EGR component 108. Also, the EGR supply branch 220 may provide coolant flow directly from the common flow branch 138 to the second sub-branch 172 for supplying coolant to the LP EGR component 110.

[0055] The EGR supply branch 220 may include a flow regulator 225. The flow regulator 225 may be configured to regulate and / or control a flow characteristic of the coolant flowing through the EGR supply branch 220. In some embodiments, the flow regulator 225 may be operable between the inlet end 222 and the outlet end 224 and fluidly connected to the EGR supply branch 220.

[0056] In some embodiments, flow regulator 225 may include an orifice with a predetermined size. The cross-sectional size of the orifice (measured perpendicular to the flow direction) may be smaller than that of the adjacent portions of supply branch 220. The size of the orifice may be configured such that the coolant flow, coolant flow rate, etc., is limited by flow regulator 225.

[0057] Alternatively, in some embodiments, the flow regulator 225 may include an EGR inlet valve 226 configured to selectively change a flow characteristic of coolant flowing through the EGR supply branch 220. In some embodiments, the EGR inlet valve 226 may be movable between a first position and a second position. In some embodiments, the first position may be a closed position to prevent substantially all coolant flow through the EGR supply branch 220. Additionally, in some embodiments, the second position may be an open position, thereby allowing flow through the EGR supply branch 220. In further embodiments, the EGR inlet valve 226 may be selectively positionable in a plurality of positions, thereby allowing flow through the supply branch 220 in more than one position; however, the flow rate (e.g.,the mass flow rate) through the EGR supply branch 220 may vary depending on the position of the EGR inlet valve 226.

[0058] In additional embodiments, the EGR inlet valve 226 may be movable between a first position, a second position, and at least one additional position. At least one of these positions may be a closed position to prevent coolant flow through the EGR supply branch 220. Also, the flow rate through the EGR supply branch 220 may vary depending on the position of the EGR inlet valve 226.

[0059] In some embodiments, the position of the EGR inlet valve 226 may be electrically controlled by a computer-based controller, processor, control logic, etc. In some embodiments, the EGR inlet valve 226 may be controlled by an electronic control unit of the vehicle 100. Further, in some embodiments, the electronic control unit may receive sensor data (e.g., coolant temperature data, coolant flow data, etc.) from the sensors 216, and with this data, the electronic control unit may change the position of the EGR inlet valve 226. In other embodiments, the position of the EGR inlet valve 226 may be mechanically controlled (i.e., without a computer controller, processor, control logic, etc.).

[0060] The EGR inlet valve 226 may include various features. In some embodiments, the EGR inlet valve 226 may include a thermostat or other components that automatically change the position of the EGR inlet valve 226 depending on the temperature of the coolant. Also, in some embodiments, the EGR inlet valve 226 may be a one-way check valve. Accordingly, the EGR inlet valve 226 may be biased toward a closed position such that there is substantially no flow through the EGR supply branch 220; however, fluid pressure at the EGR inlet valve 226 may serve to open the EGR inlet valve 226 to allow flow through the EGR inlet valve 226.

[0061] With reference to Fig. 3 and Fig. 4 different operating configurations of the cooling system 126 of Fig. 2. In each operating configuration, the coolant may circulate through the cooling system 126 along different flow paths (i.e., different flow channels).

[0062] In the illustrated embodiment, components upstream of the variable valve 168 (e.g., the engine block 103, the cylinder head 105, the HP EGR 108, the exhaust gas recirculation valve 112, the LP EGR 110, the throttle body 109, and the turbocharger component 107) may be cooled by the cooling system 126. In other words, heat from these components may be transferred to the coolant as it circulates through the cooling system 126. In contrast, components downstream of the variable valve 168 (e.g., the engine oil heater 118, the transmission fluid heater 122, the heater 124, and the radiator 132) may absorb heat from the coolant. In the case of the engine oil heater 118 and the transmission fluid heater 122, heat from the coolant may warm the respective oil within the component. In the case of the heater 124 and the cooler 132, heat can be transferred from the coolant to the air flowing around these components.

[0063] In some embodiments, the operating configuration of the cooling system 126 may be changed when the position of the engine coolant control valve 158 and / or the EGR inlet valve 226 is changed. In the operating configuration of Fig. 3, for example, the engine coolant control valve 158 is shown in an ON position, and the EGR inlet valve 226 is shown in an OFF position. In contrast, in the operating configuration of Fig. 4, for example, the engine coolant flow control valve 158 is shown in an OFF position, and the EGR inlet valve 226 is shown in an ON position. Other valves 168 (e.g., the block valve 148, the recirculation valve 112, the variable valve 168, etc.) may be in both Fig. 3 and Fig. 4 are in the same position. However, it should be understood that the cooling system 126 may have different operating configurations and / or additional operating configurations to provide other coolant flow paths without departing from the scope of the present disclosure.

[0064] In the operating configuration of Fig. 3, the coolant pump 128 may pump coolant through the common flow branch 138. This flow may be split into the first and second engine flow branches 142, 140 for providing coolant flow (and cooling) to the engine 102. This flow may combine at junction 158 and flow through the engine coolant control valve 158. The flow may split again at junction 160. Some flow may flow into port 166, and a portion of the flow may flow into the EGR branch 162. The flow in the EGR branch 162 may, as shown, deliver coolant in parallel to the HP EGR component 108, the valve 112, the LP EGR component 110, the throttle body 109, and the turbocharger component 107. This flow may then flow to the common outlet element 182 and to the second port 188 of the variable valve 168.

[0065] Accordingly, in the operating configuration of Fig. 3, the coolant flow from the engine 102 (ie, the coolant flow from the flow branches 140, 142) may be received in series by the EGR branch 162. Also, the EGR inlet valve 226 may prevent flow through the EGR supply branch 220. In some embodiments, the operating configuration of Fig. 3 may be suitable for situations in which the temperature of the engine 102 is at least equal to a predetermined threshold. For example, the operating state of the cooling system 126 may be Fig. 3 may be useful when the engine 102 is warmed up and needs to be cooled. The EGR components 108, 110, the throttle valve 109, and the turbocharger component 107 may also receive a coolant flow for cooling.

[0066] In contrast, in the operating configuration of Fig. 4, the coolant pump 128 may pump coolant through the common flow branch 138. This flow may be received by the EGR supply branch 220 and, as shown, flow into the EGR branch 162 for delivery to the HP EGR component 108, the valve 112, the LP EGR component 110, the throttle body 109, and the turbocharger component 107. This flow may then flow to the common outlet member 182 and to the port 188 of the variable valve 168.

[0067] Accordingly, in the operating configuration of Fig. 4, the engine coolant control valve 158 may prevent coolant from flowing through the engine 102. In some embodiments, the operating configuration of Fig. 4 may be suitable for situations where the temperature of the engine 102 is below a predetermined threshold. For example, the operating state of the cooling system 126 may be Fig. 4 may be useful when the engine 102 starts and is cold. By preventing coolant from flowing through the engine 102, the engine can warm up relatively quickly while still allowing cooling of the HP EGR component 108, valve 112, LP EGR component 110, throttle body 109, and turbocharger component 107.

[0068] Additional embodiments of the cooling system 126' of the present disclosure are described in Fig. 5. The cooling system 126' may be substantially similar to the embodiments discussed above, except as noted below. Components similar to those discussed above are shown in Fig. 5 with corresponding reference numerals, but with an additional prime symbol.

[0069] In this embodiment, the flow regulator 225' may be an orifice member with an opening 230' extending therethrough. The cross-sectional size of the opening 230' (measured perpendicular to the flow direction) may be smaller than that of the adjacent portions of the supply branch 220'. The size of the opening 230' may be configured such that the coolant flow, coolant flow rate, etc., is limited by the flow regulator 225'.

[0070] In the operating configuration of Fig. 5, the engine coolant control valve 158' may be in an ON position. Thus, flow may be split from the common flow branch 138' to the parallel coolant flow between the engine block 103', the cylinder head 105', and the EGR system 106'. However, the orifice 230' of the flow regulator 225' may reduce the flow through the supply branch 220', allowing the coolant pump 128' to pump coolant to each branch.

[0071] The operating configuration of Fig. 5 can be the operating configuration of Fig. 3 in that both may be suitable in situations where the engine 102' has warmed up. The operating configuration of the cooling system 126' of Fig. 5 may also include a different operating configuration substantially similar to that of Fig. 4. In particular, the engine coolant control valve 158' may be turned off, and the opening 230' may allow flow to the EGR system 106'. Thus, the engine 102' may warm up relatively quickly, and coolant may continue to be supplied to the EGR system 106', similar to the embodiments discussed above.

[0072] Thus, the cooling systems 126, 126' of the present disclosure provide selectable cooling between the engine 102, 102' and the EGR system 106, 106', as well as selectable cooling of other components. Accordingly, the cooling system 126, 126' can be varied between different configurations depending on the current operating state of the vehicle. Therefore, the vehicle and its subsystems can be efficiently operated and cooled under various operating conditions (cold weather, warm weather, cold engine, warm engine, etc.). List of reference symbols 100 motor vehicles 102 Engine 103 Engine block 104 Exhaust system 105 cylinder head 106 Exhaust gas recirculation system, EGR system 107 Turbocharger component 108 EGR component with short distance or high pressure 109 Throttle valve 110 EGR component with long distance or low pressure 112 Exhaust gas recirculation valve 114 Engine lubrication system 116 Engine oil pump 117 Oil circuit 118 Engine oil heater 119 Gearbox lubrication system 120 Fluid pump 121 Fluid circuit 122 Transmission fluid heater 124 Heating device 126 Cooling system 128 Coolant pump 130 piping system 132 coolers 134 passenger compartment 136 Pump outlet 138 common flow branch 140 first engine flow branch 142 second engine flow branch 144 intake manifold 146 Outlet section 148 Block valve 150 intake manifold 152 exhaust manifold 154 Outlet section 156 first junction 158 Engine coolant flow control valve 160 second junction 162 AGR branch 164 first feed 166 first connection 168 variable valve 170 first sub-branch 172 second sub-branch 174 third sub-branch 176 fourth sub-branch 178 first intermediate sub-branch 180 second intermediate sub-branch 181 EGR outlet 182 common outlet element 183 Current 184 third junction 185 core feed branch 186 second feed 188 second connection of the variable valve 190 Direct flow branch 191 third connection of the variable valve 192 first outlet port of the variable valve 194 second outlet port of the variable valve 196 third outlet port of the variable valve 198 fourth junction 200 Kernweg 202 Core Bypass 204 second coolant pump 206 Return branch 208 Engine oil heating branch 210 Transmission fluid heating branch 212 flow branch 214 Expansion tank 216 sensors 220 EGR supply branch 222 Admitting 224 omitted 225 flow regulator 226 EGR inlet valve 230 Opening

Claims

[1] Engine (102) for a vehicle (100), comprising: an exhaust gas recirculation system (106, EGR system) configured to receive exhaust gas produced by the engine (102) and circulate the exhaust gas back to the engine (102), the EGR system (106) comprising an EGR component (108, 110); a cooling system (126) configured to selectively cool the engine (102) and the EGR component (108, 110), the cooling system (126) including: a coolant pump (128); and a piping system (130) having a plurality of flow branches arranged to circulate coolant pumped by the coolant pump (128) through the cooling system (126), the plurality of flow branches including an engine branch defining an engine flow channel through which the coolant flows to cool an EGR branch (162) defining an EGR flow channel through which the coolant flows to cool the EGR component (108, 110), and a supply branch (220) defining a supply flow channel; wherein the cooling system (126) has a first operating configuration in which the EGR flow passage is configured to receive a coolant flow from the engine flow passage; and wherein the cooling system (126) has a second operating configuration in which the EGR flow channel is configured to receive a coolant flow from the supply flow channel instead of the engine flow channel, further comprising an EGR inlet valve (226) configured to move between a first position and a second position; wherein the EGR inlet valve (226) is configured to change a flow characteristic through the supply flow channel when the EGR inlet valve (226) moves between the first position and the second position; wherein the EGR inlet valve (226) is in the first position in the first operating configuration; wherein the EGR inlet valve (226) is in the second position in the second operating configuration; wherein the first position of the EGR inlet valve (226) is a closed position; and wherein the EGR inlet valve (226) in the closed position is configured to prevent coolant from flowing from the supply flow passage to the EGR flow passage. [2] The engine (102) of claim 1, wherein in the first operating configuration, the EGR flow passage is configured to receive coolant flow from both the engine flow passage and the supply flow passage. [3] The engine (102) of claim 1, wherein the supply branch (220) includes an orifice member (225') configured to limit flow through the supply branch (220). [4] The engine (102) of claim 1, further comprising a common branch defining a common flow channel; wherein the engine branch and the supply branch (220) extend in parallel from the common branch such that both the engine flow channel and the supply flow channel are configured to receive coolant flow from the common flow channel. [5] The engine (102) of claim 4, further comprising a direct flow branch receiving coolant flow from the common flow passage, wherein a bypass passage bypasses both the EGR flow passage and the engine flow passage. [6] The engine (102) of claim 1, further comprising a first downstream component (118, 122, 124, 132) and a second downstream component (118, 122, 124, 132); wherein the plurality of branches includes a first downstream branch and a second downstream branch; wherein the first downstream branch defines a first downstream flow channel through which the coolant flows to exchange heat with the first downstream component (118, 122, 124, 132); wherein the second downstream branch defines a second downstream flow channel through which the coolant flows to exchange heat with the second downstream component (118, 122, 124, 132); wherein the first downstream flow passage is configured to receive flow from the EGR flow passage; and wherein the second downstream flow channel is configured to receive flow from the engine flow channel. [7] The engine (102) of claim 6, wherein the plurality of branches includes a common return branch configured to return the coolant flow received from the first and second downstream flow channels to the coolant pump (128).

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