Patent ID: 6672786
Filing Date: 2004-01-06
Classification: F01D,F02F,F05D,F16B,Y10T

Abstract:
A joint assembly, comprising:a ceramic shaft portion integral with a ceramic member; a shrink fitter formed of a first material being disposed around said ceramic shaft portion and having an inner surface facing said ceramic shaft portion; a layer of solid lubricant deposited on said inner surface of said shrink fitter being in torque transmitting contact and defining a first interface surface with said ceramic shaft portion; a sleeve formed of a second material disposed around and in torque transmitting contact with said shrink fitter defining a second interface surface therebetween; one of said shrink fitter and said sleeve integral with a metal member; wherein the diameter of said first interface surface, d1, and the diameter of said second interface surface, d2, are related as d1/d2=(&agr;câˆ’&agr;1)/(&agr;2âˆ’&agr;1), where &agr;c is the coefficient of thermal expansion of said ceramic shaft portion, &agr;1 is the coefficient of thermal expansion of said first material, and &agr;2 is the coefficient of thermal expansion of said second material.