CN-122001109-A - Wedge for an electric motor

CN122001109ACN 122001109 ACN122001109 ACN 122001109ACN-122001109-A

Abstract

The rotor includes a laminated core defining poles and pole pieces. The pole pieces define slots for the coils. The outer wedge is disposed in the groove. The outer wedge includes a top portion disposed at an outer diameter of the rotor. The top portion includes an upper surface and a lower surface. The upper and lower surfaces form a continuous curve that presses against the pole piece. The upper surface creates a first seal and the lower surface creates a second seal. The outer wedge also includes a bottom portion continuously connected to the top portion and in contact with the coil wire. The base includes a winding support surface and a wedge tip surface. The winding support surface is connected to the lower surface of the top. The wedge tip surface extends along the wedge central axis toward the laminated core.

Inventors

M. R. crayvell
B. J. Heckman
GRIMMINGER ERIC F.

Assignees

通用汽车环球科技运作有限责任公司

Dates

Publication Date: 20260508
Application Date: 20241225
Priority Date: 20241108

Claims (10)

1. A wedge for a rotor including a laminated core defining an axis of rotation, magnetic poles, and pole pieces, wherein the rotor defines slots for receiving coils, the wedge comprising: An outer wedge defining a wedge central axis perpendicular to the rotational axis, wherein the outer wedge is disposed in the groove, the outer wedge comprising: a top portion disposed at an outer diameter of the rotor, the top portion comprising: An upper surface inclined away from the wedge central axis while moving radially outward and vertically from the rotor axis, wherein the upper surface compresses against the pole pieces to create a seal, and A lower surface inclined toward the wedge central axis while moving radially outward and vertically from the rotor axis, wherein the lower surface seals to the pole piece in the presence of a radial load, Wherein the upper surface and the lower surface generate a continuous curve, and A bottom portion continuously connected to the top portion, the bottom portion comprising: a winding support surface connected to a lower surface of the top portion, and A wedge tip surface, wherein the wedge tip surface extends along the wedge central axis toward the laminated core, Wherein the winding support surface and the wedge tip surface are adjacent the coil.
2. The wedge of claim 1, wherein the outer wedge includes a raised portion disposed between the lower surface of the top and the winding support surface of the bottom.
3. The wedge of claim 2, further comprising a varnish manifold defined by the raised portion and the pole piece, wherein the varnish manifold enables varnish to cover the coil and sealed space between laminations forming the laminated core.
4. The wedge of claim 1, wherein the outer wedge includes a flexible hinge at which the lower surface of the top and the bottom of the outer wedge are connected, the flexible hinge allowing the top to move independently relative to the bottom.
5. A wedge as claimed in claim 1, wherein the winding support surface forms a bevel away from the wedge central axis while moving radially outwards and perpendicular to the rotor axis.
6. The wedge of claim 1, further comprising an inner wedge disposed within a groove of the outer wedge, wherein the inner wedge matches a contour of an inner surface of the outer wedge and creates compression of the pole shoes and the winding support surface.
7. The wedge of claim 6, wherein the inner wedge defines a shaped aperture along an axial length of the wedge that increases absorption of the radial load and allows for adjustable compression stiffness from the pole to an adjacent pole.
8. The wedge of claim 6, wherein the wedge further comprises pockets on the inner wedge, the pockets being sized differently to adjust stiffness along the axial length of the wedge.
9. The wedge of claim 8, wherein the pocket is located on an upper surface of the inner wedge, wherein the upper surface of the inner wedge is disposed at the outer diameter of the rotor.
10. The wedge of claim 8, wherein a pocket is located on the side of the inner wedge, wherein the side of the inner wedge is in contact with the inner surface of the outer wedge.

Description

Wedge for an electric motor Technical Field The present disclosure relates to a wedge for an electric motor. More specifically, the present disclosure relates to a wedge for an independently energized rotor in an electric motor that compresses a coil and seals to the rotor to retain a cooling fluid therein. Background An independently excited synchronous motor (SESM) typically includes a stator and a rotor. Instead of permanent magnets in the rotor, the SESM comprises coils that generate the rotor magnetic field. Thus, the magnetic field of the rotor can be adjusted by the level of current applied to the coils. The rotor includes a laminated core having poles and pole shoes defining slots. The coil is disposed in the slot and wound around the poles. As current is applied to the coils, the rotor starts to rotate at a high speed. When rotated, the coils are strained by radial forces and may become misaligned. One solution is to insert the wedge into the slot. The wedge presses against the coil, protecting the coil and maintaining alignment. While effective, there is a need in the art for an improved wedge design that has a stronger seal between the wedge and the pole piece and that allows additional coils to be placed in the slots while maintaining compression of the coils during high rotational speeds. Disclosure of Invention According to several aspects, a wedge for a rotor is provided. The rotor includes a laminated core defining an axis of rotation, poles and pole pieces, wherein the rotor defines slots for receiving coils. The wedge includes an outer wedge defining a wedge central axis perpendicular to the rotational axis. The outer wedge is disposed in the groove. The outer wedge includes a top portion disposed at an outer diameter of the rotor. The top portion includes an upper surface that is inclined away from the wedge central axis while moving radially outward and vertically from the rotor axis. The upper surface presses against the pole piece to form a seal. The outer wedge also includes a lower surface that is inclined toward the wedge central axis while moving radially outward and vertically from the rotor axis. When radial loads are present, the lower surface seals to the pole piece. The upper and lower surfaces form a continuous curve. The outer wedge also includes a bottom portion continuously connected to the top portion. The bottom portion includes a winding support surface connected to a lower surface of the top portion. The base further includes a wedge tip surface. The wedge tip surface extends along the wedge central axis toward the laminated core. The winding support surface and wedge tip surface are adjacent to the coil. In another aspect of the present disclosure, the outer wedge includes a raised portion disposed between a lower surface of the top and a winding support surface of the bottom. In another aspect of the disclosure, the varnish manifold is defined by a boss portion and a pole piece. The varnish manifold enables varnish to cover a sealed space between the coil and the laminations forming the laminated core. In another aspect of the present disclosure, the outer wedge includes a flexible hinge located where the lower surfaces of the top and bottom of the outer wedge are connected. The flexible hinge allows the top to move independently relative to the bottom. In another aspect of the present disclosure, the winding support surface forms a bevel away from the wedge central axis while moving radially outward and perpendicular to the rotor axis. In another aspect of the disclosure, the wedge further comprises an inner wedge. The inner wedge is disposed within the groove of the outer wedge. The inner wedge matches the contour of the inner surface of the outer wedge and compresses the pole pieces and winding support surfaces. In another aspect of the present disclosure, the inner wedge defines a shaped aperture along an axial length. The shaped apertures increase the absorption of radial loads. The shaped apertures also allow for adjustable compression stiffness from pole to adjacent pole. In another aspect of the disclosure, the inner wedge includes a pocket. Each pocket is sized differently to adjust stiffness along the axial length of the wedge. In another aspect of the disclosure, the pocket is located on an upper surface of the inner wedge. The upper surface of the inner wedge is disposed at the outer diameter of the rotor. In another aspect of the disclosure, the pocket is located on a side of the inner wedge. The sides of the inner wedge are in contact with the inner surface of the outer wedge. According to several aspects, a wedge for a rotor is provided. The rotor includes a laminated core defining an axis of rotation, poles and pole pieces, wherein the rotor defines slots for receiving coils. The wedge includes an outer wedge defining a wedge central axis perpendicular to the rotational axis. The outer wedge is disposed in the groove. The outer wedge includes a top po