Magnetic bearing providing radial and axial load support for a shaft

A magnetic bearing for supporting a rotatable member including a thrust disc with respect to a stationary member, the magnetic bearing comprising:

• means associated with the stationary member for generating a radially polarized controllable electromagnetic field surrounding a portion of the rotatable member, the radially polarized electromagnetic field generating means being linked magnetically to the rotatable member through a radial air gap between the rotatable member and the stationary member and including an arcuate ring of high magnetic flux permeability, and a plurality of controllable electromagnet coils circumferentially positioned about the arcuate ring and radially paced from the rotatable member;
• means associated with the stationary member for generating a radially polarized, constant flux magnetic field, the radially polarized, constant flux magnetic field generating means being linked magnetically to the rotatable member through both the radial air gap and an axial air gap between the thrust disc and the stationary member and including a permanent magnet circumscribing the rotatable member and spaced radially outwardly from the plurality of electromagnet coils of the radially polarized electromagnetic field generating means;
• and
• means associated with the stationary member for generating an axially polarized controllable electromagnetic field, the axially polarized electromagnetic field generating means being linked magnetically to the thrust disc through the axial air gap and including a pair of electromagnet coils associated with the arcuate ring and situated on opposite sides thereof, said electromagnet coils circumscribing a portion of the rotatable member and being spaced radially outwardly from the electromagnet coils of the first radially polarized magnetic field generating means.

A magnetic bearing for supporting a rotatable member including a thrust disc with respect to a stationary member, the magnetic bearing comprising:

• means associated with the stationary member for generating a radially polarized controllable electromagnetic field surrounding a portion of the rotatable member, the radially polarized electromagnetic field generating means including an arcuate ring of high magnetic flux permeability, and a plurality of electromagnet coils circumferentially positioned about the arcuate ring and radially spaced from the rotatable member;
• a permanent magnet spaced radially outwardly from the plurality of electromagnet coils and circumscribing a portion of the rotatable member, wherein the permanent magnet is linked magnetically to the rotatable member through both a first air gap between the rotatable member and the stationary member, and a second air gap between the stationary member and the thrust disc;
• and
• means associated with the stationary member for generating an axially polarized electromagnetic field, the axially polarized electromagnet field generating means including a pair of electromagnet coils associated with the arcuate ring and situated on opposite sides thereof, said electromagnet coils circumscribing a portion of the rotatable member and being spaced radially outwardly from the electromagnet coils of the radially polarized electromagnetic field generating means.

A magnetic bearing for supporting a rotatable member including a thrust disc with respect to a stationary member, the magnetic bearing comprising:

• means associated with the stationary member for generating a radially polarized controllable electromagnetic field surrounding a portion of the rotatable member, the radially polarized electromagnetic field generating means being linked magnetically to the rotatable member through a radial air gap between the rotatable member and the stationary member and including spaced first and second arcuate rings of high magnetic flux permeability, and a plurality of electromagnet coils circumferentially positioned about each of the first and second arcuate rings and radially spaced from the rotatable member;
• means associated with the stationary member for generating a radially polarized, constant flux magnetic field, the radially polarized, constant flux magnetic field generating means being linked magnetically to the rotatable member through both the radial air gap and an axial air gap between the thrust disc and the stationary member and including a radially polarized permanent magnet spaced radially outwardly from each of the arcuate rings and circumscribing a portion of the rotatable member;
• and
• means associated with the stationary member for generating an axially polarized controllable electromagnetic field, the axially polarized electromagnetic field generating means being linked magnetically to the thrust disc through the axial air gap.

A magnetic bearing for supporting a rotatable member including a thrust disc with respect to a stationary member, the magnetic bearing comprising:

• means associated with the stationary member for generating a radially polarized controllable electromagnetic field surrounding a portion of the rotatable member, the radially polarized electromagnetic field generating means including spaced first and second arcuate rings of high magnetic flux permeability, and a plurality of electromagnet coils circumferentially positioned about each of the first and second arcuate rings and radially spaced from the rotatable member;
• a permanent magnet spaced radially outwardly from each of the arcuate rings and circumscribing a portion of the rotatable member, wherein the permanent magnet is linked magnetically to the rotatable member through both a first air gap between the rotatable member and the stationary member, and a second air gap between the stationary member and the thrust disc;
• and
• means associated with the stationary member for generating an axially polarized electromagnetic field, the axially polarized electromagnet field generating means including an electromagnetic coil associated with the arcuate ring and circumscribing a portion of the rotatable member.