Device for detecting relative motions in a bearing

In a bearing assembly having at least two relatively rotatable bearing members spaced apart to define an annular space for a plurality of rolling elements, a device having means for generating a magnetic field and means for sensing variation in the magnetic field, the rolling elements of said bearing assembly inducing variations in the magnetic flux which variations have a frequency proportional to the rotational speed of one member relative to the other member, said means for sensing variations being associated with one bearing member and seal means including a circumferentially extending shield at opposite axial ends of said annular space, each of said shields secured to one of said bearing members and in sealing contact with the other bearing member, said inducing and generating means mounted in one of said shield members whereby a sealed environment is provided for said inducing and generating means.

In a bearing assembly having at least two relatively rotatable bearing members spaced apart to define an annular space for a plurality of rolling elements, a cage for the rolling elements, a device having means for generating a magnetic field and means for sensing variation in the magnetic field, characterized by said cage having means for cutting the magnetic field lines, which means consists of a material which affects the shape of the magnetic field to produce variations having a frequency proportional to the rotational speed of one member relative to the other member, said means for sensing variations being associated with one bearing member and seal means including a circumferentially extending shield at opposite axial ends of said annular space, each of said shields secured to one of said bearing members and in sealing contact with the other bearing member, said generating means mounted in one of said shields whereby a sealed environment is provided for said generating means.

The combination comprising a bearing assembly having inner and outer relatively rotatable ring members spaced apart to define an annular space therebetween, a plurality of rolling elements in the annular space rotatable circumferentially relative to said rings, a device mounted adjacent said annular space for generating a magnetic medium and means for sensing variations in the magnetic medium, said rolling elements during operation of the bearing successively passing through said magnetic medium producing impulses sensed by said sensing means, motion of said rolling elements relative to one of said rings being proportional to the relative rotation of said rings whereby the frequency of the variations of the magnetic medium is proportional to the relative motion of said ring members and seal means including a circumferentially extending shield at opposite axial ends of said annular space, said sensing means mounted in one of said shield members, each of said shields secured to one of said bearing members and in sealing contact with the other bearing member and enclosing an annular space including said rolling elements and said generating and sensing means thereby providing a sealed environment therefor.