# US 2013/0154434 A1 · Stator core, manufacturing method therefor, and rotary electric machine that uses that stator core > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0154434 A1 - Document ID: US20130154434A1 - Status: Published application - Kind: A1 - Application number: 13/532,378 - Filed: 2012-06-25 - Published: 2013-06-20 - Earliest claimed: 2011-12-16 - Assignees: Mitsubishi Electric Corporation - Inventors: Kazuya HASEGAWA - Web page: https://patentgrep.com/patent/US20130154434A1 ## CPC - H02K 15/021: Magnetic cores - H02K 1/16: Stator cores with slots for windings - H02K 15/026: Wound cores - H02K 2201/09: Magnetic cores comprising laminations characterised by being fastened by caulking - Y10T 29/49009: Dynamoelectric machine - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract The method for manufacturing a stator core includes: a punching step in which magnetic segments are punched out of an electromagnetic steel sheet that is coated with an organic insulating coating; a laminating step in which a laminated body is formed by laminating a predetermined number of the punched magnetic segments; a first preheating step in which a welding position on a wall surface of the laminated body is heated locally from a first end to a second end in a direction of lamination to decompose an organic component in the insulating coating thermally at the welding position; and a first welding step in which the welding position at which the organic component in the insulating coating is decomposed thermally is welded from the first end to the second end in the direction of lamination to interconnect and integrate the laminated magnetic segments. ## Claims ### Claim 1 A method for manufacturing a stator core in which teeth respectively extend radially inward from an inner circumferential surface of an annular core back and are arranged at a predetermined pitch circumferentially, said method for manufacturing a stator core comprising: a punching step in which magnetic segments that have a core back portion and tooth portions are punched out of an electromagnetic steel sheet that is coated with an organic insulating coating; a laminating step in which a laminated body is formed by laminating a predetermined number of said punched magnetic segments such that said core back portions and said tooth portions are respectively stacked on each other; a first preheating step in which a welding position on a wall surface on an opposite side of said stacked core back portions of said laminated body from said tooth portions is heated locally from a first end to a second end in a direction of lamination to decompose an organic component in said insulating coating thermally at said welding position; and a first welding step in which said welding position at which said organic component in said insulating coating is decomposed thermally is welded from said first end to said second end in said direction of lamination to interconnect and integrate said laminated magnetic segments. ### Claim 2 (depends on 1) A method for manufacturing a stator core according to claim 1, wherein said welding position of said laminated body is heated locally using a semiconductor laser in said first preheating step. ### Claim 3 (depends on 1) A method for manufacturing a stator core according to claim 1, wherein: said magnetic segments are punched out of said electromagnetic steel sheet in a rectangular shape in said punching step; said laminated body that is formed by laminating said predetermined number of magnetic segments in said laminating step is a rectangular parallelepiped; and said method for manufacturing a stator core further comprises: a bending step in which said rectangular parallelepiped laminated body in which said welding position is welded by said first welding step is bent into a circular arc shape; a step in which end surfaces of said laminated bodies that are bent into the circular arc shape are abutted to each other and arranged into an annular shape; a second preheating step in which regions that extend from said first end to said second end in said direction of lamination on outer circumferential surfaces of said abutted portions of said laminated bodies that are arranged into the annular shape are heated locally to decompose an organic component in said insulating coating thermally in said regions; and a second welding step in which said regions in which said organic component in said insulating coating is decomposed thermally are welded from said first end to said second end in said direction of lamination to interconnect and integrate said abutted portions. ### Claim 4 (depends on 3) A method for manufacturing a stator core according to claim 3, wherein said regions of said laminated body are heated locally using a semiconductor laser in said second preheating step. ### Claim 5 (depends on 1) A method for manufacturing a stator core according to claim 1, wherein: said magnetic segments are punched out of said electromagnetic steel sheet in a rectangular shape in said punching step; said laminated body that is formed by laminating said predetermined number of magnetic segments in said laminating step is a rectangular parallelepiped; and said method for manufacturing a stator core further comprises: a bending step in which said rectangular parallelepiped laminated body in which said welding position is welded by said first welding step is bent into an annular shape; a second preheating step in which end surfaces of said laminated body that is bent into the annular shape are abutted to each other, and regions that extend from said first end to said second end in said direction of lamination on outer circumferential surfaces of said abutted portions are heated locally to decompose an organic component in said insulating coating thermally in said regions; and a second welding step in which said regions in which said organic component in said insulating coating is decomposed thermally are welded from said first end to said second end in said direction of lamination to interconnect and integrate said abutted portions. ### Claim 6 (depends on 5) A method for manufacturing a stator core according to claim 5, wherein said regions of said laminated body are heated locally using a semiconductor laser in said second preheating step. ### Claim 7 (depends on 1) A method for manufacturing a stator core according to claim 1, wherein: said magnetic segments are punched out of said electromagnetic steel sheet in a circular arc shape in said punching step; said laminated body that is formed by laminating said predetermined number of magnetic segments in said laminating step is a circular arc shape; and said method for manufacturing a stator core further comprises: a step in which end surfaces of said circular arc-shaped laminated bodies in which said welding position is welded by said first welding step are abutted to each other and arranged into an annular shape; a second preheating step in which regions that extend from said first end to said second end in said direction of lamination on outer circumferential surfaces of said abutted portions of said end portions of said circular arc-shaped laminated bodies are heated locally to decompose an organic component in said insulating coating thermally in said regions; and a second welding step in which said regions in which said organic component in said insulating coating is decomposed thermally are welded from said first end to said second end in said direction of lamination to interconnect and integrate said abutted portions. ### Claim 8 (depends on 7) A method for manufacturing a stator core according to claim 7, wherein said regions of said laminated body are heated locally using a semiconductor laser in said second preheating step. ### Claim 9 (depends on 1) A method for manufacturing a stator core according to claim 1, wherein: said magnetic segments are punched out of said electromagnetic steel sheet in an annular shape in said punching step; and an annular laminated body is formed by laminating a predetermined number of said magnetic segments in said laminating step. ### Claim 10 (depends on 1) A method for manufacturing a stator core according to claim 1, wherein: a magnetic segment is punched out of said electromagnetic steel sheet in a strip shape in said punching step; and an annular laminated body is formed by winding said strip-shaped magnetic segment helically in said laminating step. ### Claim 11 (depends on 1) A stator core manufactured by a method for manufacturing a stator core according to claim 1. ### Claim 12 (depends on 11) A rotary electric machine comprising a stator that uses a stator core according to claim 11.