Coulomb friction axle damper

A method for manufacturing a coulomb friction damped drive shaft, comprising:

• providing an outer shaft defined by a longitudinal axis, a first tapered portion at a first outer end and a second tapered portion at a distal second outer end;
• inserting an inner shaft through the outer shaft along the longitudinal axis, the inner shaft defined by a first uniform portion adjacent to a first inner end and a second uniform portion adjacent to a distal second inner end;
• inserting a first tapered sleeve between the first uniform portion of the inner shaft and the first tapered portion of the outer shaft;
• inserting a second tapered sleeve between the second uniform portion of the inner shaft and the second tapered portion of the outer shaft;
• and
• installing a bias mechanism to the inner shaft, the mechanism being configured to bias the first tapered sleeve along the longitudinal axis toward the second tapered sleeve to create a friction between the inner shaft and the outer shaft, wherein the friction acts on a twisting motion of the inner shaft relative to the outer shaft to coulomb friction dampen oscillations in the inner shaft.

A drive train for a motor vehicle comprising:

• a powerplant configured to generate a torque;
• a drive wheel;
• and
• a coulomb friction damped drive shaft configured to transmit the torque from the powerplant to the drive wheel, the coulomb friction damped drive shaft includes:
• an outer shaft defined by a longitudinal axis, a first tapered portion at a first outer end and a second tapered portion at a distal second outer end;
• an inner shaft inserted through the outer shaft along the longitudinal axis and defined by a first uniform portion adjacent to a first inner end and a second uniform portion adjacent to a distal second inner end;
• a first tapered sleeve inserted between the first uniform portion of the inner shaft and the first tapered portion of the outer shaft;
• and
• a second tapered sleeve inserted between the second uniform portion of the inner shaft and the second tapered portion of the outer shaft, wherein:
• the first tapered sleeve is biased along the longitudinal axis toward the second tapered sleeve to create a friction between the inner shaft and the outer shaft;
• and
• the drive shaft is configured such that the friction acts on a twisting motion of the inner shaft relative to the outer shaft to coulomb friction dampen oscillations in the inner shaft.