Torsional vibration solutions for cylinder deactivation
AssigneeEaton Intelligent Power Limited
InventorsJames E. McCarthy, Jr., Barry T. Adams
Life of this patent
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Abstract
A method for operating a 6-cylinder engine connected to a driveline including a transmission. The method includes: monitoring a rotational speed of a crankshaft of the 6-cylinder engine: monitoring a gear selection of the transmission; and operating the 6-cylinder engine in one of Order 3, Order 1.5 or Order 1 based on whether the selected Order avoids operating the 6-cylinder engine at a critical speed that corresponds to a natural harmonic frequency of the driveline, wherein priority is given to operating in Order 1.5, Order 1 then Order 3, in that order.
Claims20
A method of operating a 6-cylinder engine connected to a driveline, the method comprising:
- monitoring a rotational speed of a crankshaft of the 6-cylinder engine;
- monitoring a gear selection of a transmission of the driveline;
- and
- in response to the transmission being in one of gears 1 through 5 and the speed of the crankshaft being less than 1160 RPM, selectively operating the 6-cylinder engine by firing three cylinders and deactivating three cylinders;
- and
- in response to the transmission being in one of gears 1 through 5 and the speed of the crankshaft being less than 1720 RPM, selectively operating the 6-cylinder engine by firing two or four cylinders.
A method for operating a 6-cylinder engine connected to a driveline, the method comprising:
- monitoring a rotational speed of a crankshaft of the 6-cylinder engine;
- monitoring a gear selection of a transmission of the driveline;
- and
- selectively operating the 6-cylinder engine in one of Order 3, Order 1.5 or Order 1 based on the following criteria in the following order:
- first, operating the 6-cylinder engine in Order 1.5 in response to the rotational speed of the crankshaft not being within a predetermined differential speed of a first critical speed of the crankshaft for the engine, wherein the first critical speed is associated with the gear selected and Order 1.5 and causes the driveline to vibrate at a natural harmonic frequency of the driveline, wherein Order 1.5 is firing three cylinders and deactivating three cylinders,
- second, operating the 6-cylinder engine in Order 1 in response to the rotational speed of the crankshaft not being within a predetermined differential speed of a second critical speed of the crankshaft for the engine, wherein the second critical speed is associated with the gear selected and Order 1 and causes the driveline to vibrate at a natural harmonic frequency of the driveline, wherein Order 1 is firing two or four cylinders,
- else, operating the 6-cylinder engine in Order 3, wherein Order 3 is firing six cylinders.
A method for operating a 6-cylinder engine connected to a driveline including a transmission, the method comprising:
- monitoring a rotational speed of a crankshaft of the 6-cylinder engine;
- monitoring a gear selection of the transmission;
- and
- operating the 6-cylinder engine in one of Order 3, Order 1.5 or Order 1 based on whether the selected Order avoids operating the 6-cylinder engine at a critical speed that corresponds to a natural harmonic frequency of the driveline, wherein priority is given to operating in Order 1.5, Order 1 then Order 3, in that order, wherein Order 3 is firing six cylinders, Order 1.5 is firing three cylinders, and Order 1 is firing two or four cylinders, and wherein the critical speed is associated with the gear selected and the operating Order.
Dependencies are inferred from the claim text.