Electromagnetic clutches

In an electromagnetic clutch comprising bearing means, a first rotatable member of magnetic material rotatably supported on said bearing means and including an outer annular cylindrical portion, an inner annular cylindrical portion, and an axial end plate portion connecting between said outer and inner annular cylindrical portions at an axial end thereof to form an annular hollow portion therebetween, an annular electromagnet stationarily disposed in said hollow portion and comprising an annular magnetic housing and an annular electromagnetic coil therein, a second rotatable shaft member, a shaft seal around said second rotatable shaft member, a hub member secured on a projected end of said second rotatable shaft member, magnetic armature means supported on and around said hub member with a radial gap therebetween so as to be capable of limited axial movement and facing said axial end plate portion with an axial gap therebetween, said armature means being attracted to the axial end plate portion when said electromagnet is energized, the improvement which comprises:

• a magnetic ring fixedly fitted into said inner annular cylindrical portion in an axial end adjacent to said axial end plate portion, whereby said inner annular cylindrical portion is substantially thicker at said axial end thereof than the other part thereof, said magnetic ring being provided with an annular flange axially outwardly extending from the axial end thereof into said radial gap between said magnetic armature means and said hub member, an inner surface of said magnetic ring being formed in a tapered surface to diverge toward the extended end of said annular flange, whereby oil leaked from said shaft seal is guided along said tapered surface to be discharged outside through said radial gap.