US 12,445,002 B2
Magnet-embedded rotating machine with magnets having different coercive forces
Yoshihito Sanga, Osaka (JP); and Yoshinari Asano, Osaka (JP)
Assigned to DAIKIN INDUSTRIES, LTD., Osaka (JP)
Filed by DAIKIN INDUSTRIES, LTD., Osaka (JP)
Filed on Feb. 10, 2023, as Appl. No. 18/108,400.
Application 18/108,400 is a continuation of application No. PCT/JP2021/033554, filed on Sep. 13, 2021.
Claims priority of application No. 2020-160786 (JP), filed on Sep. 25, 2020.
Prior Publication US 2023/0198325 A1, Jun. 22, 2023
Int. Cl. H02K 1/276 (2022.01)
CPC H02K 1/2766 (2013.01) [H02K 2213/03 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A magnet-embedded rotating machine comprising:
a rotor rotatable about a shaft; and
a stator having a facing surface radially facing a peripheral surface of the rotor with a gap interposed therebetween,
the rotor including
a first magnet embedded in an area that is radially spaced from the facing surface of the stator by a first distance or longer, and
a second magnet embedded in an area that is radially spaced from the facing surface of the stator by a second distance or longer, the second distance being longer than the first distance,
Hco(A)>Hco(B),
Hci(A)>Hci(B),
Hco(A)>Hci(A), and
{Hco(A)/Hci(A)}>{Hco(B)/Hci(B)}, with
Hco(A) representing a coercive force of the first magnet within a first temperature range corresponding to temperatures at a startup of the rotating machine,
Hco(B) representing a coercive force of the first magnet within a second temperature range corresponding to temperatures during steady-state driving of the rotating machine,
Hci(A) representing a coercive force of the second magnet within the first temperature range,
Hci(B) representing a coercive force of the second magnet within the second temperature range,
the first magnet being a neodymium magnet, or a neodymium magnet in which a portion of neodymium is replaced with lanthanum or cerium, and
the second magnet being a samarium-cobalt magnet, or a neodymium magnet in which a portion of neodymium is replaced with lanthanum or cerium.