IP Library Granted Patent US 12665447
Granted Patent B2
US 12665447 · App. 18/718,678 · Granted Jun 23, 2026

Laminated iron core and rotating electric machine using the same

Inventors: Matahiro Komuro (Tokyo, JP); Tomohiro Tabata (Tokyo, JP); Yusuke Asari (Tokyo, JP); Shohei Terada (Tokyo, JP)
Assignee: Hitachi, Ltd.
H02K1/02H02K2213/03
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Quick Facts
Patent No.
US 12665447
App. No.
18/718,678
Granted
Jun 23, 2026
Kind
B2
Abstract

There is provided a laminated iron core in which a plurality of types of soft magnetic iron plates are laminated. The plurality of types of the soft magnetic iron plates include a first soft magnetic iron plate and a second soft magnetic iron plate, the first soft magnetic iron plate and the second soft magnetic iron plate are alternately laminated, the first soft magnetic iron plate has higher nitrogen content and higher saturation magnetic flux density than the second soft magnetic iron plate, and the second soft magnetic iron plate has lower coercive force than the first soft magnetic iron plate.

Claims (40)

1 . A laminated iron core in which a plurality of types of soft magnetic iron plates are laminated, wherein

the plurality of types of soft magnetic iron plates include a first soft magnetic iron plate and a second soft magnetic iron plate,

the first soft magnetic iron plate and the second soft magnetic iron plate are alternately laminated,

the first soft magnetic iron plate has higher nitrogen content and higher saturation magnetic flux density than the second soft magnetic iron plate, and

the second soft magnetic iron plate has lower coercive force than the first soft magnetic iron plate.

2 . The laminated iron core according to claim 1 , wherein the first soft magnetic iron plate is an iron-cobalt-nitrogen-based iron plate having a chemical composition containing 1 atom % or more and 25 atom % or less of cobalt, 2 atom % or more and 10 atom % or less of nitrogen, and 0 atom % or more and 1 atom % or less of vanadium, with the balance containing iron and an impurity.

3 . The laminated iron core according to claim 1 , wherein a ratio of saturation magnetic flux density of the second soft magnetic iron plate to saturation magnetic flux density of the first soft magnetic iron plate is 0.8 or more and less than 1.

4 . The laminated iron core according to claim 1 , wherein the second soft magnetic iron plate has saturation magnetic flux density of 2.0 T or more.

5 . The laminated iron core according to claim 1 , wherein

each of the first soft magnetic iron plate and the second soft magnetic iron plate has a thickness of 0.01 mm or more and 1 mm or less, and

a thickness of the first soft magnetic iron plate is one time or more and five times or less a thickness of the second soft magnetic iron plate.

6 . The laminated iron core according to claim 1 , wherein the soft magnetic iron plate as an outermost layer has a magnetostriction constant equal to or less than a magnetostriction constant of another one of the soft magnetic iron plates.

7 . The laminated iron core according to claim 6 , wherein the soft magnetic iron plate as the outermost layer is a third soft magnetic iron plate different from the first soft magnetic iron plate and the second soft magnetic iron plate.

8 . The laminated iron core according to claim 1 , wherein an electrically insulating layer having electrical resistivity of 1×10 6 Ω·cm or more is interposed between adjacent ones of the soft magnetic iron plates.

9 . A rotating electric machine comprising a laminated iron core, wherein the laminated iron core is the laminated iron core according to claim 1 .

10 . The laminated iron core according to claim 2 , wherein a ratio of saturation magnetic flux density of the second soft magnetic iron plate to saturation magnetic flux density of the first soft magnetic iron plate is 0.8 or more and less than 1.

11 . The laminated iron core according to claim 2 , wherein the second soft magnetic iron plate has saturation magnetic flux density of 2.0 T or more.

12 . The laminated iron core according to claim 3 , wherein the second soft magnetic iron plate has saturation magnetic flux density of 2.0 T or more.

13 . The laminated iron core according to claim 10 , wherein the second soft magnetic iron plate has saturation magnetic flux density of 2.0 T or more.

14 . The laminated iron core according to claim 2 , wherein

each of the first soft magnetic iron plate and the second soft magnetic iron plate has a thickness of 0.01 mm or more and 1 mm or less, and

a thickness of the first soft magnetic iron plate is one time or more and five times or less a thickness of the second soft magnetic iron plate.

15 . The laminated iron core according to claim 3 , wherein

each of the first soft magnetic iron plate and the second soft magnetic iron plate has a thickness of 0.01 mm or more and 1 mm or less, and

a thickness of the first soft magnetic iron plate is one time or more and five times or less a thickness of the second soft magnetic iron plate.

16 . The laminated iron core according to claim 4 , wherein

each of the first soft magnetic iron plate and the second soft magnetic iron plate has a thickness of 0.01 mm or more and 1 mm or less, and

a thickness of the first soft magnetic iron plate is one time or more and five times or less a thickness of the second soft magnetic iron plate.

17 . The laminated iron core according to claim 10 , wherein

each of the first soft magnetic iron plate and the second soft magnetic iron plate has a thickness of 0.01 mm or more and 1 mm or less, and

a thickness of the first soft magnetic iron plate is one time or more and five times or less a thickness of the second soft magnetic iron plate.

18 . The laminated iron core according to claim 11 , wherein

each of the first soft magnetic iron plate and the second soft magnetic iron plate has a thickness of 0.01 mm or more and 1 mm or less, and

a thickness of the first soft magnetic iron plate is one time or more and five times or less a thickness of the second soft magnetic iron plate.

19 . The laminated iron core according to claim 12 , wherein

each of the first soft magnetic iron plate and the second soft magnetic iron plate has a thickness of 0.01 mm or more and 1 mm or less, and

a thickness of the first soft magnetic iron plate is one time or more and five times or less a thickness of the second soft magnetic iron plate.

20 . The laminated iron core according to claim 13 , wherein

each of the first soft magnetic iron plate and the second soft magnetic iron plate has a thickness of 0.01 mm or more and 1 mm or less, and

a thickness of the first soft magnetic iron plate is one time or more and five times or less a thickness of the second soft magnetic iron plate.