Patent ID: 7731006
Filing Date: 2010-06-08
Classification: F16D

Abstract:
1. A clutch assembly for a fan drive system of an engine comprising: a central piston member in a clutch housing feeding a pressure chamber; a translatable clutch piston positioned within said clutch housing and in communication with said pressure chamber, said translatable clutch piston movable between a piston neutral position and a piston activated position, wherein air pressure fed through said central piston member into said pressure chamber moves said translatable clutch piston from said piston neutral position to said piston activated position; a rotating drive shaft positioned within said clutch housing; a cone clutch member in communication with said translatable clutch piston such that said cone clutch member is moved from a clutch engaged position to a clutch disengaged position in response to said translatable clutch piston moving from said piston neutral position to said piston activated position, said cone clutch member engaging aid rotating drive shaft when in said clutch engaged position; a clutch spring member positioned between said rotating drive shaft and said central piston member, said clutch spring member biasing said cone clutch member into said clutch engaged position with a clutch engagement force; at least on movable carrier member positioned adjacent said clutch spring member; and a needle bearing assembly positioned between said rotating drive shaft and said clutch housing, said needle bearing assembly having an axial length and an inner diameter, wherein the ratio of said axial length to said inner diameter is in the range of about 0.37 to about 0.50.