Laminated iron core, method for manufacturing laminated iron core, and punch for caulking formation used in the method

Abstract

The invention provides a laminated iron core, a method for manufacturing the laminated iron core, and a punch for caulking formation used in the method. Solid stack riveting stack can also be carried out by means of thin plates of thickness of 0.2mm or less. The laminated core (10) is formed with a plurality of iron chips (12) punched out from a sheet (14) having a thickness of 0.2 mm or less; one end portion is continuous, the other parts are separated and tilted; the overlapping pieces (15,16) of the adjacent iron chips(12) are fitted into the opening portions (19, 20) to connect the plurality of iron chips (11,12); the overlapping rivet protrusions (15,16)are arranged at intervals (S), and the other end portions of the pair of overlapping rivet protrusions (15, 16) are formed in the direction or phase away from each other. The manufacturing method includes a stack riveting protrusions forming step, a punching step, and a laminating step, and the overlapping rivet protrusions (15, 16) are formed in the stack riveting process. And a punch portion (15, 16) for forming the above-mentioned stacking protrusions(15,16) is provided symmetrically with respect to the punch (30).

Description

technical field [0001] The present invention relates to a laminated iron core formed by laminating a plurality of core pieces punched out of a thin plate material with a thickness of 0.2 mm or less, a method of manufacturing the same, and a punch for forming a riveting used therefor. Background technique [0002] The laminated iron core constituting the motor is manufactured, for example, by punching out a thin electromagnetic steel sheet into a predetermined shape using a press line, stacking a predetermined number of sheets, and connecting them by riveting. [0003] As this clinching, there are known a clinching in which an electrical steel sheet is half pierced (so-called flat clinching) and a clinching in which an electrical steel sheet is separated to form a slope (so-called V clinching). [0004] In recent years, as the performance of electric motors has improved, there has been an increase in laminated iron cores using thinner electrical steel sheets. The thinner the...

AI Technical Summary

Problems solved by technology

[0005] However, it is difficult to form V-stack riveting in a thin plate with a thickness of 0.2mm or less.

[0006] The main reason for this is that usually in the formation of V-stack riveting, the bottom surface is bulged and the slope is stretched, so cracks occur from the bottom surface.

[0007] In addition, in the case of V-stack riveting, there is also a problem that the periphery of the area where the V-stack riveting is formed is deformed because both inclined surfaces are pressed into the lower core sheet to connect the adjacent core sheets.

Images