Liquid thermosetting resin composition for insulating stator coil of rotating electric machine

Patent metadata

Field	Value
Publication number	US-9890277-B2
Application number	US-201214405528-A
Country	US
Kind code	B2
Filing date	Jun 15, 2012
Priority date	Jun 15, 2012
Publication date	Feb 13, 2018
Grant date	Feb 13, 2018

Abstract

The liquid thermosetting resin composition of the present invention comprises an epoxy resin in which at least one selected from the group consisting of a linear epoxy resin having a degree of polymerization of 2 or more and an epoxy acrylate resin and at least one selected from the group consisting of a novolac-type epoxy resin and a naphthalene-type epoxy compound are linked to each other via an ether linkage, and which has a weight average molecular weight of from 2,000 to 10,000. When the liquid thermosetting resin composition of the present invention is used for insulating a stator coil of a rotating electric machine, mechanical characteristics can be improved without causing a reduction in the heat resistance.

First claim

The invention claimed is:

1. A liquid thermosetting resin composition, comprising:
an epoxy resin in which at least one selected from the group consisting of a linear epoxy resin having a degree of polymerization of 2 or more and an epoxy acrylate resin, and at least one of a novolac-type epoxy resin, are linked to each other via an ether linkage,
wherein the novolac-type epoxy resin is a phenol novolac-type epoxy resin of formula (4):

wherein n represents a positive integer, and
wherein a weight average molecular weight of the epoxy resin is from 2,000 to 10,000.

2. The composition according to claim 1 , wherein the novolac-type epoxy resin has a degree of polymerization of 3 or more.

3. The composition according to claim 1 , wherein the epoxy resin is obtained by reacting 2 to 50 epoxy equivalents of the at least one selected from the group consisting of a linear epoxy resin and an epoxy acrylate resin with 100 epoxy equivalents of the novolac-type epoxy resin.

4. The composition according to claim 1 , further comprising: at least one selected from the group consisting of a bismaleimide and an isocyanurate.

5. A rotating electric machine, comprising: a rotor; and a stator being disposed outside or inside of the rotor and having a plurality of slots, wherein the plurality of slots comprise a winding wire coated with a cured product of the liquid thermosetting resin composition according to claim 1 .

6. The composition according to claim 1 , wherein the epoxy resin is obtained by reacting 3 to 40 epoxy equivalents of the at least one selected from the group consisting of a linear epoxy resin and an epoxy acrylate resin with 100 epoxy equivalents of the novolac-type epoxy resin.

7. A method of manufacturing a rotating electric machine, the method comprising:
mixing an epoxy resin in which at least one selected from the group consisting of a linear epoxy resin having a degree of polymerization of 2 or more and an epoxy acrylate resin, and at least one of a novolac-type epoxy resin, are linked to each other via an ether linkage, wherein the novolac-type epoxy resin is a phenol novolac-type epoxy resin of formula (4):

wherein n represents a positive integer, and

wherein a weight average molecular weight of the epoxy resin is from 2,000 to 10,000, with at least one selected from the group consisting of a bismaleimide and an isocyanurate, to obtain a liquid thermosetting resin composition;
subjecting a plurality of slots of a stator to insulation treatment, followed by winding an electric wire around the slots a predetermined number of times;
coating the stator with the liquid thermosetting resin composition, followed by curing the liquid thermosetting resin composition, to obtain an insulation-treated stator; and
disposing a rotor inside or outside of the stator.

8. A liquid thermosetting resin composition, comprising:
an epoxy resin in which at least one selected from the group consisting of a linear epoxy resin having a degree of polymerization of 2 or more and an epoxy acrylate resin, and at least one of a novolac-type epoxy resin, are linked to each other via an ether linkage,
wherein the novolac-type epoxy resin is a cresol novolac-type epoxy resin of formula (5):

wherein:
m represents 1 or 2;
n represents a positive integer;
R represents H or an alkyl group having 1 to 3 carbon atoms; and
X represents a direct linkage or a methylene group having 1 to 3 carbon atoms, and
wherein a weight average molecular weight of the epoxy resin is from 2,000 to 10,000.

9. The composition according to claim 8 , wherein the novolac-type epoxy resin has a degree of polymerization of 3 or more.

10. The composition according to claim 8 , wherein the epoxy resin is obtained by reacting 2 to 50 epoxy equivalents of the at least one selected from the group consisting of a linear epoxy resin and an epoxy acrylate resin with 100 epoxy equivalents of the novolac-type epoxy resin.

11. The composition according to claim 8 , wherein the epoxy resin is obtained by reacting 3 to 40 epoxy equivalents of the at least one selected from the group consisting of a linear epoxy resin and an epoxy acrylate resin with 100 epoxy equivalents of the novolac-type epoxy resin.

12. The composition according to claim 8 , further comprising: at least one selected from the group consisting of a bismaleimide and an isocyanurate.

13. A rotating electric machine, comprising: a rotor; and a stator being disposed outside or inside of the rotor and having a plurality of slots, wherein the plurality of slots comprise a winding wire coated with a cured product of the liquid thermosetting resin composition according to claim 8 .

14. A method of manufacturing a rotating electric machine, the method comprising:
mixing an epoxy resin in which at least one selected from the group consisting of a linear epoxy resin having a degree of polymerization of 2 or more and an epoxy acrylate resin, and at least one of a novolac-type epoxy resin, are linked to each other via an ether linkage, wherein the novolac-type epoxy resin is a cresol novolac-type epoxy resin of formula (5):

wherein:
m represents 1 or 2;
n represents a positive integer;
R represents H or an alkyl group having 1 to 3 carbon atoms; and
X represents a direct linkage or a methylene group having 1 to 3 carbon atoms, and wherein a weight average molecular weight of the epoxy resin is from 2,000 to 10,000, with at least one selected from the group consisting of a bismaleimide and an isocyanurate, to obtain a liquid thermosetting resin composition;
subjecting a plurality of slots of a stator to insulation treatment, followed by winding an electric wire around the slots a predetermined number of times;
coating the stator with the liquid thermosetting resin composition, followed by curing the liquid thermosetting resin composition, to obtain an insulation-treated stator; and
disposing a rotor inside or outside of the stator.

Assignees

• Yamamoto Shigeyuki
• Mabuchi Takahiro
• Kubo Kazuki
• Awano Yuhei
• Mitsubishi Electric Corp

Inventors

• Yamamoto Shigeyuki
• Mabuchi Takahiro
• Kubo Kazuki
• Awano Yuhei

Classifications

• C08L2201/02

  Flame or fire retardant/resistant · CPC title

• H02K3/30 Primary

  Windings characterised by the insulating material · CPC title

• C08L63/04 Primary

  Epoxynovolacs · CPC title

• Y10T29/49009

  Dynamoelectric machine · CPC title

• C08L2203/206

  use in coating or encapsulating of electronic parts · CPC title