Rotor balance ring and oil flinger
A turbocharger includes a rotor rotatably mounted within the turbocharger about a rotor axis, a balance ring provided at an axial end of the rotor, and a cutout provided in the balance ring, the cutout having an open end extending radially outward from the rotor axis.
1 . A turbocharger comprising:
a magnetic rotor rotatably mounted within the turbocharger about a rotor axis, the magnetic rotor having a magnetic core disposed within a shell;
a balance ring disposed in and provided at an axial end of the magnetic rotor and having a base and a flange extending axially from the base away from the axial end of the magnetic rotor, the base being contained within the shell;
a cylindrical shaped cutout provided in the flange of the balance ring, the cutout having an open end extending radially outward from the rotor axis and a cutout axis aligned to an axis of the magnetic rotor;
a stator positioned radially outward from the magnetic rotor and axially aligned with the magnetic rotor;
an airgap between an inner surface of the stator and an outer surface of the magnetic rotor; and
a shaft rotatable about the rotor axis;
wherein the balance ring is configured to be an oil flinger to eject oil from the cutout as the balance ring rotates, and the cutout is configured to have a diameter based on a measured imbalance of the magnetic rotor.
2 . The turbocharger of claim 1 , wherein the cutout is disposed on an outer circumferential surface of the balance ring and includes a cutout wall, the entire cutout wall being exposed to the open end.
3 . The turbocharger of claim 1 , wherein the cutout has a cutout axis that is transverse to the rotor axis and extends radially outward from the rotor axis.
4 . The turbocharger of claim 3 , wherein a height measurement between the cutout axis and an axial plane of a top surface of the flange is based on a measure of imbalance of the magnetic rotor combined with the balance ring.
5 . The turbocharger of claim 1 , wherein the cutout has a cutout axis that is parallel to the rotor axis.
6 . The turbocharger of claim 5 , wherein a radial measurement between the cutout axis and the rotor axis is based on a measure of imbalance of the magnetic rotor combined with the balance ring.
7 . The turbocharger of claim 1 , wherein the cutout is a concave cutout.
8 . A turbocharger comprising:
a magnetic rotor rotatably mounted within the turbocharger about a rotor axis, the magnetic rotor having a magnetic core disposed within a shell, the magnetic rotor having a first axial end and a second axial end opposite the first axial end;
a first balance ring of the magnetic rotor forming the first axial end and having a first base and a first flange extending axially from the first base past the first axial end of the rotor, the first base being located within the shell, the first flange of the first balance ring extending away from the shell and including a first cylindrical shaped cutout having a first open end extending radially outward from the rotor axis and a first cutout axis aligned to an axis of the magnetic rotor;
a second balance ring of the magnetic rotor forming the second axial end and having a second base and a second flange extending axially from the second base past the second axial end of the rotor, the second base being located within the shell, the second flange of the second balance ring extending away from the shell and including a second cylindrical shaped cutout having a second open end extending radially outward from the rotor axis and a second cutout axis aligned to axis of the magnetic rotor;
a stator;
an airgap between the stator and the rotor; and
a shaft rotatable about the rotor axis;
wherein the first balance ring and the second balance ring are configured to be an oil flinger to eject oil from the first cutout and the second cutout as the first balance ring and the second balance ring rotate, and the first cutout and the second cutout are configured to have a diameter based on a measured imbalance of the magnetic rotor.
9 . The turbocharger of claim 8 , wherein:
the first cutout is disposed on an outer circumferential surface of the first balance ring and includes a first cutout wall, the entire first cutout wall being exposed to the first open end; and
the second cutout is disposed on an outer circumferential surface of the second balance ring and includes a second cutout wall, the entire second cutout wall being exposed to the second open end.
10 . The turbocharger of claim 8 , wherein the first cutout is a first cylindrical cutout having a first cutout axis that is transverse to the rotor axis and extends radially outward from the rotor axis, and the second cutout is a second cylindrical cutout having a second cutout axis that is transverse to the rotor axis and extends radially outward from the rotor axis.
11 . The turbocharger of claim 8 , wherein the first cutout is a first cutout having a first cutout axis that is parallel to the rotor axis and the second cutout is a second cutout having a second cutout axis that is parallel to the rotor axis.
12 . The turbocharger of claim 8 , wherein a first cutout axis of the first cutout coincides with a second cutout axis of the second cutout.
13 . The turbocharger of claim 8 , wherein either one or both of the first cutout and the second cutout is a concave cutout.
14 . A rotor for a turbocharger comprising:
a magnetic core mounted on a shaft of the turbocharger, the magnetic core having a shell;
a balance ring disposed on a first axial end of the magnetic core and having a base and a flange extending axially from the base away from the first axial end of the magnetic core and extending radially away from the shaft of the turbocharger, the base being contained within the shell; and
a cylindrical shaped cutout provided on an outer circumferential surface of the flange of the balance ring, the cutout having an open end extending radially outward from a rotor axis and a cutout axis aligned to an axis of the magnetic core,
wherein the balance ring is configured to be an oil flinger to eject oil from the cutout as the balance ring rotates, and the cutout is configured to have a diameter based on a measured imbalance of the magnetic rotor.
15 . The rotor of claim 14 , wherein a size of the cutout is based on a measure of imbalance of the magnetic core combined with the balance ring.
16 . The rotor of claim 14 , wherein the flange of the balance ring extends axially past a first end of the shell.