Magnetic strain wave gear device

US12451789B2 · US · B2

Patent metadata
FieldValue
Publication numberUS-12451789-B2
Application numberUS-202118551711-A
CountryUS
Kind codeB2
Filing dateAug 2, 2021
Priority dateAug 2, 2021
Publication dateOct 21, 2025
Grant dateOct 21, 2025

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  1. Title

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  2. Abstract

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  3. Assignees and inventors

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  4. Key dates

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  5. First independent claim

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  6. CPC / IPC classifications

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  7. Citations and related patents

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Abstract

Official abstract text for this publication.

Provided is a magnetic strain wave gear device that makes it possible to achieve both improvement of the efficiency of assembly work and suppression of decrease in energy conversion efficiency. A magnetic strain wave gear device includes: a stator having a stator core, a stator winding, and a stator magnet; a first rotor; and a second rotor. The second rotor includes a second rotor core provided with a plurality of rotor magnet insertion holes and a plurality of rotor magnets inserted into the plurality of respective rotor magnet insertion holes. The first rotor includes a cylindrical first rotor core and a first rotor end plate. The first rotor end plate has a rotor magnet passage hole through which the rotor magnets can be inserted into the rotor insertion holes from outside in a direction of a rotation shaft.

First claim

Opening claim text (preview).

The invention claimed is: 1. A magnetic strain wave gear device comprising: a stator having a stator core provided with a plurality of slots in a circumferential direction, a stator winding disposed in each of the slots, and a stator magnet; a first rotor disposed radially inward of the stator with a gap interposed therebetween; and a second rotor disposed radially inward of the first rotor with a gap interposed therebetween, the second rotor being concentric with a rotation shaft of the first rotor, wherein the second rotor includes a second rotor core provided with a plurality of rotor magnet insertion holes arrayed in the circumferential direction and a plurality of rotor magnets inserted into the plurality of respective rotor magnet insertion holes, the first rotor includes a first rotor core having a cylindrical shape and a first rotor end plate fastening the first rotor core and the rotation shaft to each other and located outward of the second rotor in a direction of the rotation shaft, and the first rotor end plate has a rotor magnet passage hole through which the rotor magnets can be inserted into the rotor magnet insertion holes of the second rotor core from outside in the direction of the rotation shaft. 2. The magnetic strain wave gear device according to claim 1 , wherein each of the rotor magnets includes a plurality of division magnet pieces arrayed in at least one of the circumferential direction and an axial direction of the second rotor. 3. The magnetic strain wave gear device according to claim 2 , wherein the first rotor end plate has a shape with a plurality of spokes, a width of at least one of openings between the plurality of spokes is larger than a width of each of the rotor magnet insertion holes, and the one opening is the rotor magnet passage hole. 4. The magnetic strain wave gear device according to claim 2 , wherein the first rotor end plate has a disc shape, the first rotor end plate has at least one opening having a width larger than a width of each of the rotor magnet insertion holes, and the one opening is the rotor magnet passage hole. 5. The magnetic strain wave gear device according to claim 1 , wherein the first rotor end plate has a shape with a plurality of spokes, a width of at least one of openings between the plurality of spokes is larger than a width of each of the rotor magnet insertion holes, and the one opening is the rotor magnet passage hole. 6. The magnetic strain wave gear device according to claim 1 or 2 , wherein the first rotor end plate has a disc shape, the first rotor end plate has at least one opening having a width larger than a width of each of the rotor magnet insertion holes, and the one opening is the rotor magnet passage hole.

Assignees

Inventors

Classifications

  • Machines with one stator and two {or more} rotors · CPC title

  • using intermediate parts, e.g. spiders · CPC title

  • Machines characterised by the modularity of some components · CPC title

  • Magnets embedded in the magnetic core, e.g. interior permanent magnets [IPM] · CPC title

  • Stator cores with permanent magnets · CPC title

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Frequently asked questions

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What does patent US12451789B2 cover?
Provided is a magnetic strain wave gear device that makes it possible to achieve both improvement of the efficiency of assembly work and suppression of decrease in energy conversion efficiency. A magnetic strain wave gear device includes: a stator having a stator core, a stator winding, and a stator magnet; a first rotor; and a second rotor. The second rotor includes a second rotor core provide…
Who is the assignee on this patent?
Mitsubishi Electric Corp, Univ Osaka
What technology area does this patent fall under?
Primary CPC classification H02K49/102. Mapped technology areas include Electricity.
When was this patent published?
Publication date Tue Oct 21 2025 00:00:00 GMT+0000 (Coordinated Universal Time) (B2). Legal status and post-grant events are not shown on this page.
What related patents are in patentsdb?
We list 1 related publication on this page (citations in our corpus or others sharing the same primary CPC).