Magnet retention arrangement for high speed rotors
AssigneeElectric Boat Corporation
InventorsPieter Van Dine, Alberto Franco, Spyro Pappas, Michael Gheorghiu
Life of this patent
Estimating the term…
Abstract
In the rotor arrangement disclosed in the specification a rotor has a central shaft with a surrounding rim to which a circumferential array of pole pieces is mechanically affixed by screws. An array of permanent magnets each mounted between an adjacent pair of pole pieces is radially retained in position by a slot wedge having edges shaped to interlock with the outer side portions of the adjacent pole pieces. The outer surfaces of the pole pieces and slot wedges form a uniform cylindrical outer surface which is covered by an outer wrap of fiber reinforced polymer material to assure that the magnets are retained radially in position.
Claims6
A permanent magnet rotor arrangement comprising:
- a rotor having a hub and a rim mechanically connected to the hub;
- an array of pole pieces made of magnetic material circumferentially distributed around the rim;
- and
- an array of permanent magnets circumferentially distributed around the rim and interspersed between the pole pieces, each magnet being radially retained by a nonmagnetic wedge having interlocking engagement with adjacent pole pieces on opposite sides of the magnet, the radially outer surfaces of the pole pieces and the wedges forming a smooth cylindrical surface of substantially uniform diameter;
- and
- a fiber wrap layer surrounding the cylindrical surface to facilitate radial retention of the magnets and having a smooth outer surface to reduce windage losses at high rotational speeds.
Dependencies are inferred from the claim text.