Drive train

Abstract

A drive train including an internal combustion engine having a predefined number of cylinders, and operable in a first engine operating state in which all cylinders are in operation, and a second operating state in which some of the cylinders are not in operation. The drive train has a torsional-vibration damping system with at least one torsional-vibration damper and at least one centrifugal-force pendulum. In order to improve the torsional-vibration behavior of the drive train, a centrifugal-force pendulum and optionally a torsional-vibration damper are adapted to control torsional-vibration behavior of the engine in one operating state, and a torsional-vibration damper and optionally a second centrifugal-force pendulum are adapted to control the torsional-vibration behavior of the engine in the other engine operating state.

1 : A drive train comprising:
 an internal combustion engine having a predefined number of cylinders and operable in a first engine operating state in which all the cylinders are in operation, and operable in a second engine operating state in which some of the cylinders are not in operation,   a torsional-vibration damping system including at least one torsional-vibration damper and at least one centrifugal pendulum, wherein at least one of a centrifugal pendulum and a torsional-vibration damper is adapted to a control engine torsional-vibration behavior during the first engine operating state, and at least one of a torsional-vibration damper and a second centrifugal pendulum is adapted to control engine torsional-vibration behavior during the second engine operating state.   
     
     
         2 : The drive train in accordance with  claim 1 , wherein a first torsional-vibration damper is a divided flywheel having at least one damper stage, and a second torsional-vibration damper is a torsional-vibration damper in a clutch disc having at least one damper stage of a friction clutch arranged between the internal combustion engine and a transmission in the drive train. 
     
     
         3 : The drive train in accordance with  claim 2 , wherein a centrifugal pendulum is arranged on at least one of a primary inertial mass and a secondary inertial mass of the first torsional-vibration damper. 
     
     
         4 : The drive train in accordance with  claim 2 , wherein a centrifugal pendulum is arranged on the second torsional-vibration damper. 
     
     
         5 : The drive train in accordance with  claim 3 , wherein a centrifugal pendulum is arranged on at least one of a primary inertial mass and a secondary inertial mass of the first torsional-vibration damper, and the first torsional-vibration damper operates to control engine torsional-vibration behavior during the first engine operating state, and the first torsional-vibration damper operates to control engine torsional-vibration behavior during the second engine operating state. 
     
     
         6 : The drive train in accordance with  claim 3 , wherein the first torsional-vibration damper operates to control engine torsional-vibration behavior during the first engine operating state, and a centrifugal pendulum arranged on at least one of a primary inertial mass and a secondary inertial mass of the first torsional-vibration damper, and the first torsional-vibration damper operate to control engine torsional-vibration behavior during the second engine operating state. 
     
     
         7 : The drive train in accordance with  claim 4 , wherein the centrifugal pendulum arranged on the second torsional-vibration damper and a first damper stage of high stiffness operate to control the torsional-vibration behavior of the engine during the first operating state, and a second damper stage of low stiffness of the first torsional-vibration damper operates to control the torsional-vibration behavior of the engine during the second engine operating state. 
     
     
         8 : The drive train in accordance with  claim 4 , wherein a centrifugal pendulum arranged on a secondary inertial mass of the first torsional-vibration damper operates to control the torsional-vibration behavior of the engine during the first engine operating state, and a centrifugal pendulum arranged on the second torsional-vibration damper operates to control the torsional-vibration behavior of the engine during the second engine operating state. 
     
     
         9 : The drive train in accordance with  claim 8 , including a damper stage of high stiffness of the first torsional-vibration damper ( 615 ) is adapted that operates to control the torsional-vibration behavior of the engine during the second engine operating state. 
     
     
         10 : The drive train in accordance with  claim 8 , including a damper stage of low stiffness of the first torsional-vibration damper operates to control the torsional-vibration behavior of the engine during the second engine operating state. 
     
     
         11 : The drive train in  claim 4 , wherein the centrifugal pendulum arranged on the second torsional-vibration damper ( 519 ,  619 ) is adapted operates to control the torsional-vibration behavior of the engine during the first operating state, and a centrifugal pendulum arranged on a secondary inertial mass of the first torsional-vibration damper operates to control the torsional-vibration behavior of the engine during the second engine operating state.