Process of structuring stator of built-in motor

• US 5,168,662 A
• Filed: 01/15/1992
• Issued: 12/08/1992
• Est. Priority Date: 12/28/1988
• Status: Expired due to Term

• Current Assignee: Fanuc Ltd (Fanuc Corporation)
• Original Assignee: Fanuc Ltd (Fanuc Corporation)
• Inventors: Hayashi, Yoshiyuki, Numai, Kazuhisa, Kimijima, Masami, Nakamura, Kosei
• Primary Examiner(s): Kisliuk, Bruce M.
• Assistant Examiner(s): MORGAN, EILEEN P
• Application Number:
  US07/820,836
• Time in Patent Office: 328 Days
• Field of Search: 51/165.75, 51/289 R, 51/323, 310/42, 310/43, 310/264, 310/260, 310/208, 310/216
• US Class Current: 451/46
• CPC Class Codes: H02K 1/04 characterised by the material used for insulating the magnetic circuit or parts thereof
• CPC Class Codes: H02K 1/16 Stator cores with slots for windings
• CPC Class Codes: H02K 2201/09 Magnetic cores comprising laminations characterised by being fastened by caulking
• CPC Class Codes: Y10S 174/20 Stator

Abstract

The stator of a built-in motor must be firmly and accurately mounted on the spindle head housing or the like of a machine tool. A stator core (10), i.e., a principal component of the stator is welded partially at the circumference (14) thereof, and then the circumference of the stator core (10) held by a mandrel is finished to an accurate outside diameter by grinding. The stator core (10) thus constructed is subjected to a deformation with a lapse of time after the mandrel has been removed. To solve this problem, each lamination (12) of the stator core (10) is coated with a thermosetting adhesive, to be thereby joined together, and each lamination (12) is provided with a plurality of pressed projections (22) to be joined together by weld portions (20) on the circumference of the stator core (10), or each lamination (12) is joined together by pressing a serrated bar (26) into a bore (24) thereof, without a pressed projection (22).

Claims

1. A process of structuring a stator core of a built-in motor from a plurality of sheet-like high-permeability steel laminations, comprising the steps, performed in the recited order exclusive of other steps, of:

preparing a plurality of sheet-like high-permeability steel laminations;

applying a thermosetting adhesive to entire surfaces of each of said plurality of sheet-like high-permeability steel laminations to thereby form a film-like coating of said thermosetting adhesive having a thickness of less than ten microns;

superimposing said plurality of sheet-like high-permeability steel laminations coated with said thermosetting adhesive to thereby form a laminated core structure;

heating said laminated core structure having superimposed laminations therein to substantially 150 degrees centigrade, for a predetermined time, to thereby harden said thermosetting adhesive film between adjacent said sheet-like high-permeability steel laminations to join the laminations firmly together; and

after said heating step, mounting said laminated core structure on a mandrel suited for subjecting said laminated core structure to a grinding operation by a grinding machine at an outer diameter of said laminated core structure, and grinding said laminated core structure of sheet-like high-permeability steel laminations to thereby establish a predetermined outer diameter of said laminated core structure for said stator core.

2. A process as recited in claim 1 wherein said heating step further includes compressing said laminated core structure.