Universal fan for fan clutch

Claim 1

A fan for attachment to the driven housing of a fluid coupling type fan clutch for an automotive internal combustion engine, wherein said driven housing has an axis of rotation and is provided fan mounting means comprising a plurality of bosses each of which has a planar fan mounting surface, with said planar fan mounting surfaces lying in a common plane which is normal to said axis of rotation, with each said boss having a threaded aperture opening to a respective said fan mounting surface with said threaded apertures being equidistant from said axis of rotation, and a supporting shoulder having an arcuate surface extending axially outwardly from each said boss and with all points on the arcuate surfaces of said shoulders being equidistant from said axis of rotation, and with said fan comprising: a. a hub portion having a central opening which has a central axis and the periphery of which is defined by a first set of angularly spaced apart arcuate inner edges located at a first radial distance from said central axis and a second set of angularly spaced apart arcuate outer edges located at a second radial distance from said central axis, with said second radial distance being greater than said first radial distance, with each respective said arcuate outer edge of said first set being disposed between respective adjacent arcuate inner edges of said second set; b. said hub portion further having a first set of bolt receiving apertures that are located equidistant from said central axis and a respective one of which is centered on the radial bisector of a respective arcuate outer edge, with the radial distance to said second set of apertures being greater than the radial distance to said first set of apertures; c. said first set of arcuate inner edges and said first set of bolt receiving apertures being sized for mating with the respective bosses, threaded apertures and supporting shoulders of a said driven housing of a first size; d. said second set of arcuate outer edges and said second set of bolt receiving apertures being sized for mating with the respective bosses, threaded apertures and supporting shoulders of a said driven housing of a second size.