Turbocharged internal combustion engine

• US 5,611,202 A
• Filed: 03/31/1995
• Issued: 03/18/1997
• Est. Priority Date: 05/11/1994
• Status: Expired due to Term

• Current Assignee: Daimler AG (Mercedes-Benz Group AG)
• Original Assignee: Mercedes-Benz AG (Mercedes-Benz Group AG)
• Inventors: Schillings, Herbert, Sumser, Siegfried, Schmidt, Erwin
• Primary Examiner(s): KOCZO JR, MICHAEL
• Application Number:
  US08/414,587
• Time in Patent Office: 718 Days
• Field of Search: 60/605.2, 60/612
• US Class Current: 60/605.2
• 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 37/007 with exhaust-driven pumps arranged in parallel , e.g. at least one pump supplying alternatively
• CPC Class Codes: F02B 37/18 by bypassing exhaust from the inlet to the outlet of turbine or to the atmosphere
• CPC Class Codes: F02B 37/24 by using pumps or turbines with adjustable guide vanes
• CPC Class Codes: F02B 47/08 the substances including exhaust gas
• CPC Class Codes: F02M 26/08 for engines having two or more intake charge compressors or exhaust gas turbines, e.g. a turbocharger combined with an additional compressor
• CPC Class Codes: F02M 26/34 with compressors, turbines or the like in the recirculation passage
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

In a turbocharged internal combustion engine having at least two exhaust gas turbochargers arranged in parallel, each including a turbine connected by an exhaust conduit to the engine exhaust to be driven thereby and a compressor connected by an air supply conduit to the intake of the engine for supplying compressed air thereto, an exhaust gas recirculation conduit connected to the exhaust conduit upstream of the turbine leads to the air supply conduit of only one of exhaust gas turbochargers and a check valve is arranged in the air supply duct upstream of the jointure thereof with the exhaust gas recirculation conduit so as to involve only one of the exhaust gas turbochargers in the exhaust gas recirculation.

Claims

1. A turbocharged internal combustion engine including at least first and second exhaust gas turbochargers arranged in parallel, each comprising a turbine with an inlet end and an outlet end and a compressor with a pressure side and a suction side, said internal combustion engine having an air intake with an air supply conduit having first sections leading to said compressors and second sections extending from the pressure side of each compressor to an engine intake, said engine having an exhaust with an exhaust conduit connected to the inlet end of each of said turbines, the turbine of said second exhaust gas turbocharger including a control arrangement for controlling the flow of exhaust gases therethrough, and an exhaust gas recirculation conduit extending between said exhaust conduit and said first section of the air supply conduit of said second exhaust gas turbocharger so that the exhaust gas recirculated through said recirculation conduit can be compressed by said second exhaust gas turbocharger, said first section of said air supply conduit of said second turbocharger including a check valve and said recirculation conduit being connected to said exhaust conduit upstream of the turbine of said second exhaust gas turbocharger and to said air supply conduit downstream of said check valve.

2. An internal combustion engine according to claim 1, wherein an exhaust gas pipe extends from the exhaust gas recirculation conduit to the compressor of said second exhaust gas turbocharger and is connected thereto so as to feed into a diffuser portion disposed at the pressure side of said compressor so that the exhaust gas conducted through said exhaust gas pipe does not flow fully through said compressor.

3. An internal combustion engine according to claim 1, wherein the compressor of said first exhaust gas turbocharger is designed for withstanding normal air temperatures for handling engine intake air and the compressor of said second exhaust gas turbocharger is capable of withstanding high temperatures for handling also exhaust gases, the arrangement being such that exhaust gas recirculation is attended to only by said second exhaust gas turbocharger.

4. An internal combustion engine according to claim 1, wherein an intercooler is arranged only in the second section of said air supply conduit of said first turbocharger.

5. An internal combustion engine according to claim 3, wherein an intercooler is arranged only in said second section of said air supply conduit of said first turbocharger.