Permanent magnet rotor shaft assembly and method
AssigneeSkf Magnetic Mechatronics
InventorsLateb Ramdane, Joaquim Da Silva
Life of this patent
Estimating the term…
Abstract
A permanent magnet rotor shaft assembly for a high speed electrical machine provides a permanent magnet cylindrical core having a longitudinal axis, the cylindrical core being axially compressed by first and second end shafts and being radially compressed by a sleeve made of a non-magnetic high strength metal. At least one of the first and second end shafts includes, facing the cylindrical core, a central shoulder head that cooperates with a mating central recess made in a central portion of a front face of the cylindrical core. An easy concentric alignment of the first and second end shafts with the permanent magnet cylindrical core is allowed while inserting the sleeve and the stiffness of the assembled set is enhanced.
Claims15
A permanent rotor shaft assembly for an electrical machine, comprising:
- a permanent magnet cylindrical core having a longitudinal axis, the cylindrical core being axially compressed by first and second end shafts and being radially compressed by a sleeve made of a non-magnetic high strength metal, wherein
- at least one of the first and second end shafts includes, in its portion facing the cylindrical core, a central shoulder head that cooperates with a mating central recess made in a central portion of a front face of the cylindrical core.
A rotary high speed electrical machine having tip speeds up to 300 m/s, comprising:
- a permanent rotor shaft assembly having a permanent magnet cylindrical core having a longitudinal axis, the cylindrical core being axially compressed by first and second end shafts and being radially compressed by a sleeve made of a non-magnetic high strength metal, wherein
- at least one of the first and second end shafts includes, in its portion facing the cylindrical core, a central shoulder head that cooperates with a mating central recess made in a central portion of a front face of the cylindrical core.
A method for making a permanent rotor shaft assembly for an electrical machine, comprising the steps of:
- forming a permanent magnet cylindrical core having a longitudinal axis, bonding a first end shaft onto one end of the permanent magnet cylindrical core,
- bonding a second end shaft onto the other end of the permanent magnet cylindrical core,
- installing a sleeve made of a non-magnetic high strength metal in interference fit fashion around the permanent magnet cylindrical core and the portions of the first and second end shafts adjacent to the permanent magnet cylindrical core, so that the cylindrical core be axially compressed by the first and second end shafts and be radially compressed by the sleeve, and wherein the method further includes;
- providing at least one central shoulder head in the first and second end shafts, in its portion facing the cylindrical core,
- providing in a central portion of a front face of the cylindrical core, at least one mating central recess, which is adapted to cooperate with the at least one central shoulder head, and
- mounting the at least one central shoulder head in the at least one mating central recess, before inserting the sleeve made of a non-magnetic high strength metal in interference fit fashion around the permanent magnet cylindrical core and the portions of the first and second end shafts adjacent to the permanent magnet cylindrical core.
Dependencies are inferred from the claim text.