文档介绍：3 Torsional Vibration
Crankshaft torsional vibration has been a problem
with aircraft engines since before World War I.
Crankshaft torsional vibration happens because each
power stroke tends to slightly twist the shaft. When
the power stroke subsides, the crankshaft untwists.
One would think that something as massive as a Figure Puck-type Damper (Pratt & Whitney)
crankshaft would not twist significantly, but any piece
of metal always deflects a bit when a force is applied, Curtiss-Wright employed Roland Chilton, a prolific
and when large amounts of power are generated, the designer of many aviation engine and accessory
forces can e huge indeed. The effects of mechanisms. Chilton immediately designed a
torsional vibration can be amplified by a phenomenon pendulum mechanism that was vastly superior to
called torsional resonance. Each crankshaft design Taylor’s puck-type damper. See Figure . Chilton
has a natural torsional frequency like the note of a received a U. S. patent for his design, which is called
ringing bell or sound of a vibrating guitar string. If this variously the “Chilton damper” or “bifilar damper”.
natural frequency coincides with the torsional Three months after Taylor proposed the damper to
frequency of the crankshaft, the effects can be Curtiss-Wright, they were delivering engines
devastating, resulting in broken crankshafts, lost equip