Cooling system having variable coolant flow paths for exhaust gas recirculation system

• US 10,196,960 B2
• Filed: 03/09/2017
• Issued: 02/05/2019
• Est. Priority Date: 03/09/2017
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Saindon, William, Bilancia, Michele
• Primary Examiner(s): Tran, Long T
• Application Number:
  US15/454,902
• Publication Number:
  US 20180258830A1
• Time in Patent Office: 698 Days
• CPC Class Codes: F01P 2003/027 Cooling cylinders and cylinder heads in parallel
• CPC Class Codes: F01P 2005/105 Using two or more pumps
• CPC Class Codes: F01P 2005/125 Driving auxiliary pumps electrically
• CPC Class Codes: F01P 2007/146 using valves
• CPC Class Codes: F01P 2025/31 Cylinder temperature
• CPC Class Codes: F01P 2025/32 Engine outcoming fluid temperature
• CPC Class Codes: F01P 2025/33 Cylinder head temperature
• CPC Class Codes: F01P 2025/36 Heat exchanger mixed fluid temperature
• CPC Class Codes: F01P 2025/50 using two or more temperature sensors
• CPC Class Codes: F01P 2025/52 Heat exchanger temperature
• CPC Class Codes: F01P 2060/04 Lubricant cooler
• CPC Class Codes: F01P 2060/045 for transmissions
• CPC Class Codes: F01P 2060/08 Cabin heater
• CPC Class Codes: F01P 2060/12 Turbo charger
• CPC Class Codes: F01P 2060/16 Outlet manifold
• CPC Class Codes: F01P 2060/18 Heater
• CPC Class Codes: F01P 3/02 Arrangements for cooling cylinders or cylinder heads
• CPC Class Codes: F01P 3/18 Arrangements or mounting of liquid-to-air heat-exchangers such arrangements on cylinders or cylinder heads F01P3/04; relative to vehicles B60K11/04
• CPC Class Codes: F01P 3/20 Cooling circuits not specific to a single part of engine or machine F01P3/22 takes precedence
• CPC Class Codes: F01P 5/10 Pumping liquid coolant; Arrangements of coolant pumps
• CPC Class Codes: F01P 7/14 : the coolant being liquid
• CPC Class Codes: F01P 7/165 : characterised by systems with two or more loops
• CPC Class Codes: F02M 26/02 : EGR systems specially adapted for supercharged engines
• CPC Class Codes: F02M 26/28 : with liquid-cooled heat exchangers
• CPC Class Codes: F02M 26/30 : Connections of coolers to other devices, e.g. to valves, heaters, compressors or filters; Coolers characterised by their location on the engine
• CPC Class Codes: F02M 26/33 : controlling the temperature of the recirculated gases

Abstract

A cooling system selectively cools an engine and an exhaust gas recirculation (EGR) component of the engine. The cooling system includes a plumbing system with a plurality of flow branches, including an engine branch, an EGR branch, and a feed branch. The engine branch defines an engine flow passage through which the coolant flows to cool the engine. The EGR branch defines an EGR flow passage through which the coolant flows to cool the EGR component. The feed branch defines a feed 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 feed flow passage instead of the engine flow passage.

Claims

1. An engine for a vehicle comprising:

an exhaust gas recirculation (EGR) system configured to receive exhaust gas produced by the engine and recirculate the exhaust gas back to the engine, the EGR system including an EGR component;

a cooling system configured for selective cooling of the engine and the EGR component, the cooling system including;

a coolant pump; and

a plumbing system with a plurality of flow branches arranged to circulate coolant pumped by the coolant pump through the cooling system, the plurality of flow branches including an engine branch defining an engine flow passage through which the coolant flows to cool the engine, an EGR branch defining an EGR flow passage through which the coolant flows to cool the EGR component, and a feed branch defining a feed flow passage;

wherein 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; and

wherein the cooling system has a second operating configuration in which the EGR flow passage is configured to receive coolant flow from the feed flow passage instead of the engine flow passage.

2. The engine 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 feed flow passage.

3. The engine of claim 1, further comprising an EGR feed valve configured to move between a first position and a second position;

wherein the EGR feed valve is configured to change a flow characteristic through the feed flow passage as the EGR feed valve moves between the first position and the second position;

wherein the EGR feed valve is in the first position in the first operating configuration; and

wherein the EGR feed valve is in the second position in the second operating configuration.

4. The engine of claim 3, wherein the first position of the EGR feed valve is a closed position;

and

wherein the EGR feed valve, in the closed position, is configured to prevent coolant from flowing from the feed flow passage to the EGR flow passage.

5. The engine of claim 3, wherein the EGR feed valve, in the first position, allows a first coolant flow rate from the feed flow passage to the EGR flow passage;

wherein the EGR feed valve, in the second position, allows a second coolant flow rate from the feed flow passage to the EGR flow passage; and

wherein the first coolant flow rate is less than the second coolant flow rate.

6. The engine of claim 3, wherein the EGR feed valve includes a one-way check valve.

7. The engine of claim 1, wherein the feed branch includes an orifice member configured to limit flow through the feed branch.

8. The engine of claim 1, further comprising a common branch that defines a common flow passage;

wherein the engine branch and the feed branch extend in parallel from the common branch such that both the engine flow passage and the feed flow passage are configured to receive coolant flow from the common flow passage.

9. The engine of claim 8, further comprising a direct flow branch that receives coolant flow from the common flow passage, wherein the direct flow branch bypasses both the EGR flow passage and the engine flow passage.

10. The engine of claim 1, further comprising a first downstream component and a second downstream component;

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 passage through which the coolant flows to exchange heat with the first downstream component;

wherein the second downstream branch defines a second downstream flow passage through which the coolant flows to exchange heat with the second downstream component; and

wherein the first downstream flow passage is configured to receive flow from the EGR flow passage; and

wherein the second downstream flow passage is configured to receive flow from the engine flow passage.

11. The engine of claim 10, wherein the first downstream component is at least one of an engine oil heater, a transmission oil heater, and a heater coil;

and

wherein the second downstream component is a radiator.

12. The engine of claim 10, wherein the plurality of branches includes a common return branch configured to return coolant flow received from both the first and second downstream flow passages to the coolant pump.

13. An engine for a motor vehicle comprising:

an exhaust gas recirculation (EGR) system configured to receive exhaust gas produced by the engine and recirculate the exhaust gas back to the engine, the EGR system including an EGR component;

a cooling system configured for selective cooling of the engine and the EGR component, the cooling system including;

a coolant pump; and

a plumbing system with a plurality of flow branches arranged to circulate coolant pumped by the coolant pump through the cooling system to the engine and to the EGR system;

wherein the cooling system is operable in a first operating configuration to fluidly connect the engine to the EGR system in series and a second operating configuration to fluidly connect the engine to the EGR system in parallel.

14. The engine of claim 13, wherein, in the first operating configuration, the plumbing system fluidly connects the engine and the EGR system such that the EGR system is downstream of the engine and receives coolant flow from the engine.

15. The engine of claim 13, wherein the plurality of flow branches comprises an EGR feed branch with an EGR feed valve configured to move between a first position and a second position;

wherein, in the first operating configuration, the EGR feed valve is in the first position to prevent coolant from flowing through the EGR feed branch; and

wherein, in the second operating configuration, the EGR feed valve is in the second position to allow coolant to flow through the EGR feed branch to the EGR system.

16. The engine of claim 15, wherein the EGR feed valve comprises a one-way check valve.

17. The engine of claim 15, wherein the plurality of flow branches further comprises a common branch that defines a common flow passage from the pump and an engine branch that defines an engine flow passage that extends from the common branch and provides coolant flow to the engine, wherein the EGR feed branch extends from the common branch in parallel to the engine branch.

18. The engine of claim 17, further comprising a direct flow branch that receives coolant flow from the common flow passage, wherein the direct flow branch bypasses both the EGR system and the engine system.

19. The engine of claim 17, wherein the plurality of flow branches comprises an EGR branch configured to provide coolant to the EGR system in the first configuration;

wherein the EGR branch is configured to provide coolant to the EGR system in the second configuration; and

wherein the EGR feed branch includes a downstream end that is fluidly connected to the EGR branch, upstream of the EGR system.

20. The engine of claim 19, wherein the EGR branch comprises a plurality of sub-branches that are fluidly connected in parallel;

wherein the plurality of sub-branches includes a first sub-branch configured to provide coolant to a first EGR component of the EGR system;

wherein the plurality of sub-branches includes a second sub-branch configured to provide coolant to a second EGR component of the EGR system;

wherein the plurality of sub-branches includes a third sub-branch configured to provide coolant to at least one of a throttle and a turbocharger component.