Working fluid circuit for a turbocharged engine having exhaust gas recirculation

• US 6,786,210 B2
• Filed: 06/21/2002
• Issued: 09/07/2004
• Est. Priority Date: 06/21/2002
• Status: Expired due to Fees

• Current Assignee: Detroit Diesel Corporation (Mercedes-Benz Group AG)
• Original Assignee: Detroit Diesel Corporation (Mercedes-Benz Group AG)
• Inventors: Kennedy, Lawrence C., Crawford, Edward F.
• Primary Examiner(s): WOLFE JR, WILLIS RAY
• Application Number:
  US10/177,216
• Publication Number:
  US 20030234009A1
• Time in Patent Office: 809 Days
• Field of Search: 123/568.11, 123/568.12, 123/568.16, 123/568.17, 123/568.18, 123/568.21, 123/568.22, 123/563, 606/052, 605/99
• US Class Current: 123/568.12
• CPC Class Codes: F02B 29/0418 the intake air cooler having a bypass or multiple flow paths within the heat exchanger to vary the effective heat transfer surface
• CPC Class Codes: F02B 29/0431 Details or means to guide the ambient air to the heat exchanger, e.g. having a fan, flaps, a bypass or a special location in the engine compartment
• CPC Class Codes: F02B 29/0456 Air cooled heat exchangers
• CPC Class Codes: F02B 29/0468 Water separation or drainage means
• CPC Class Codes: F02B 29/0475 the intake air cooler being combined with another device, e.g. heater, valve, compressor, filter or EGR cooler, or being assembled on a special engine location
• CPC Class Codes: F02B 29/0493 Controlling the air charge temperature
• CPC Class Codes: F02B 75/22 with cylinders in V, fan, or star arrangement
• CPC Class Codes: F02M 26/05 High pressure loops, i.e. wherein recirculated exhaust gas is taken out from the exhaust system upstream of the turbine and reintroduced into the intake system downstream of the compressor
• CPC Class Codes: F02M 26/10 having means to increase the pressure difference between the exhaust and intake system, e.g. venturis, variable geometry turbines, check valves using pressure pulsations or throttles in the air intake or exhaust system
• CPC Class Codes: F02M 26/47 the characteristics being temperatures, pressures or flow rates
• CPC Class Codes: F28D 1/05316 Assemblies of conduits connected to common headers, e.g. core type radiators F28D1/05366 takes precedence
• CPC Class Codes: F28F 2250/06 Derivation channels, e.g. bypass
• CPC Class Codes: F28F 27/02 for controlling the distribution of heat-exchange media between different channels static flow control means in header boxes F28F9/026; arrangements of guide plates or guide vanes F28F9/22, F28F25/12
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

The working fluid circuit of the present invention includes an exhaust gas passage through which exhaust gas under pressure flows from the internal combustion engine, a charge air passage, and a turbocharger. An exhaust gas recirculation passage extends between the exhaust gas passage and the charge air passage, but bypasses the turbocharger and provides a path for recirculating a predetermined amount of exhaust gas into the charge air passage in such a way that the exhaust gas and the charge air are mixed together. An intake passage provides intake air to the internal combustion engine. A single charge air cooler is operatively interconnected to and provides fluid communication between the charge air passage and the intake passage and acts to cool the mixed charge air and the recirculated exhaust gas prior to induction into the internal combustion engine through the intake passage.

Claims

1. An engine working fluid circuit for a turbocharged internal combustion engine that employs exhaust gas recirculation, said working fluid circuit comprising:

an exhaust gas passage through which exhaust gas under pressure flows from the internal combustion engine, a charge air passage, and a turbo charger operatively driven by the exhaust gas flowing from the internal combustion engine and acting to provide pressurized air to said charged air passage;

an exhaust gas recirculation passage extending between said exhaust gas passage and said charge air passage bypassing said turbo charger and providing a path for recirculating a predetermined amount of exhaust gas into said charge air passage so as to add mix the exhaust gas with the charge air;

an intake passage for providing intake air to the internal combustion engine;

a single charge air cooler including an inlet operatively connected in fluid communication with said charge air passage and an outlet operatively connected in fluid communication with said intake passage, said single charge air cooler further including a plurality of cooling passages spaced from one another and extending between said inlet and said outlet that may be exposed to a flow of ram air, said plurality of cooling passages thereby operatively interconnecting and providing fluid communication between said charge air passage and said intake passage while providing a cooling path for the mixed charged air and recirculated exhaust gas; and

at least one bypass passage extending between said inlet and said outlet of said single charge air cooler separate from said plurality of cooling passages and adapted to provide fluid communication between said inlet and said outlet, said bypass passage having a bypass valve movable between open and closed positions to proportionally control the flow of mixed charge air and recirculated exhaust gas between said cooling passages and said bypass passage.

2. An engine working fluid circuit as set forth in claim 1 wherein said single charge air cooler includes a condensation sensor adapted to detect a build-up of condensation within said cooler.

3. An engine working fluid circuit as set forth in claim 1 further including an exhaust gas recirculation valve operatively disposed in said exhaust gas recirculation passage and acting to control the flow of exhaust gas from said exhaust gas passage into said charge air passage.

4. An engine working fluid circuit as set forth in claim 3 further including a venturi defined at the fluid connection between said charge air passage and said exhaust gas recirculation passage to assist in drawing flow from said exhaust gas recirculation passage into said charge air passage.

5. An engine working fluid circuit as set forth in claim 4 further including a pressure sensor disposed between said exhaust gas recirculation valve and said venturi and adapted to sense the flow of exhaust gas through said exhaust gas recirculation passage.