Method for operating and valve drive for a multicylinder internal combustion engine
AssigneeDr. Ing. h.c.F. Porsche Aktiengesellschaft
InventorsHartmut Voss, Joachin Grunberger
Life of this patent
Estimating the term…
Abstract
An engine is operated with two groups of cylinders, one of which groups is constantly powered and a second of said groups is selectively operated by cutting it in and out. The second group of cylinders is cut in and out by switching the valve lift of the associated charge-changing valves. The valve lift of the constantly operated cylinder group is also independently variable so that in both operating states of the second cylinder group, consumption-optimized valve lifts can be set for the first cylinder group.
Claims13
Method of operating a multicylinder internal combustion engine with a first constantly operated cylinder group and a second cylinder group that can be cut in and out independently of the first cylinder group, said method comprising:
- cutting out the second cylinder group in an engine lower load range,
- cutting in the second cylinder group in an engine upper load range,
- cutting out the second cylinder group and operating the first cylinder group with a short valve lift during engine idle operation,
- cutting out the second cylinder group and operating the first cylinder group with a long valve lift during an engine lower partial load range, and
- cutting out the second cylinder group and operating the first cylinder group with a short valve lift during an engine upper partial load range.
Control assembly for operating a multicylinder internal combustion engine with a first constantly operated cylinder group and a second cylinder group that can be cut in and out independently of the first cylinder group, said control assembly comprising:
- means for cutting out the second cylinder group in an engine lower load range,
- means for cutting in the second cylinder group in an engine upper load range,
- means for cutting out the second cylinder group and operating the first cylinder group with a short valve lift during engine idle operation,
- means for cutting out the second cylinder group and operating the first cylinder group with a long valve lift during an engine lower partial load range, and
- means for cutting out the second cylinder group and operating the first cylinder group with a short valve lift during an engine upper partial load range.
An internal combustion engine comprising:
- a first piston and cylinder group which in use is operating during all engine operation conditions,
- a second piston and cylinder group which in use is selectively operating only during certain engine operation conditions, and
- a controlling assembly for controlling operation of the engine, including:
- means for cutting out the second cylinder group in an engine lower load range,
- means for cutting in the second cylinder group in an engine upper load range,
- means for cutting out the second cylinder group and operating the first cylinder group with a short valve lift during engine idle operation,
- means for cutting out the second cylinder group and operating the first cylinder group with a long valve lift during an engine lower partial load range, and
- means for cutting out the second cylinder group and operating the first cylinder group with a short valve lift during an engine upper partial load range.
Dependencies are inferred from the claim text.