	US 7,509,805 B2
	Control of exhaust to a turbo of internal combustion engine
Erik Karlsson, Stockholm (Sweden)
Assigned to SAAB Automobile AB, (Sweden)
Filed on Oct. 06, 2005, as Appl. No. 11/244,571.
Claims priority of application No. 0402409 (SE), filed on Oct. 06, 2004.
Prior Publication US 2006/0070382 A1, Apr. 06, 2006
Int. Cl. F02B 33/44 (2006.01); F02B 37/00 (2006.01); F02B 37/007 (2006.01); F02B 37/013 (2006.01)

U.S. Cl. 60—612 [123/562]

13 Claims

1. A method for regulating an internal combustion engine, the engine comprising:

a plurality of engine cylinders, each cylinder having at least one first and one second exhaust port and a respective associated first and second exhaust valves for opening and closing the first and the second exhaust ports, wherein the first and second exhaust valves are deactivated or activated during operation of the engine,

at least one first and one second exhaust manifold, the first exhaust manifold being flow-connected to the respective first exhaust ports and the second exhaust manifold being flow-connected to the respective second exhaust ports;

a turbo unit for supercharging charge air being delivered to the cylinders, the turbo unit comprising at least one first and one second exhaust gas turbine, wherein the first exhaust gas turbine is flow connected to the first exhaust manifold and the second exhaust gas turbine is flow-connected to the second exhaust manifold;

an exhaust gas chamber operable to flow-connect the first and the second exhaust manifolds upstream of the exhaust gas turbines in the exhaust gas flow;

the method comprising:

operating at least one of the first exhaust valves in an active position and operating at least one of the second exhaust valves in an inactive position when the internal combustion engine is operating in a first engine speed range (I), and

operating a throttle valve arranged in the exhaust gas chamber in a closed position to separate the first and the second exhaust manifolds during the first engine speed range (I).