Method of manufacturing laminated iron core

Patent metadata

Field	Value
Publication number	US-11117181-B2
Application number	US-201716082698-A
Country	US
Kind code	B2
Filing date	Mar 7, 2017
Priority date	Mar 11, 2016
Publication date	Sep 14, 2021
Grant date	Sep 14, 2021

Abstract

A method of manufacturing a laminated iron core includes: inserting a plurality of electrical steel strips in a superposed state to feed rolls including a pair of upper and lower feed rolls that are driven by a drive device to feed the electrical steel strips in a superposed state into a die having a plurality of punching processes in sequence; joining a part or all of the superposed electrical steel strips together before entering the die or at an upstream stage portion of the die after feeding out the electrical steel strips from the pair of upper and lower feed rolls; and punching simultaneously the plurality of electrical steel strips in a superposed state in the die.

First claim

The invention claimed is:

1. A method of manufacturing a laminated iron core, the method comprising:
inserting a plurality of electrical steel strips in a superposed state to feed rolls including a pair of upper and lower feed rolls that are driven by a drive device to feed the electrical steel strips in a superposed state into a die having a plurality of punching processes in sequence;
joining a part or all of the superposed electrical steel strips together before entering the die or at an upstream stage portion of the die after feeding out the electrical steel strips from the pair of upper and lower feed rolls; and
punching simultaneously the plurality of electrical steel strips in a superposed state in the die,
wherein the upper feed roll rotates in synchronization with the lower feed roll, and
an operation timing of the upper feed roll and the lower feed roll is adjusted to be simultaneous.

2. The method according to claim 1 , wherein surface roughness Ra of the pair of upper and lower feed rolls is 0.3 μm or more.

3. The method according to claim 2 , further comprising correcting, by a shift correction mechanism installed at a position within 700 mm from a biting position of the pair of upper and lower feed rolls in a conveying direction of electrical steel strips, shift in a width direction of the electrical steel strips.

4. The method according to claim 3 , wherein a rolling force applied to the pair of upper and lower feed rolls is controlled within a range of more than or equal to 1000 N and less than or equal to 2500 N.

5. The method according to claim 2 , wherein a rolling force applied to the pair of upper and lower feed rolls is controlled within a range of more than or equal to 1000 N and less than or equal to 2500 N.

6. The method according to claim 1 , further comprising correcting, by a shift correction mechanism installed at a position within 700 mm from a biting position of the pair of upper and lower feed rolls in a conveying direction of electrical steel strips, shift in a width direction of the electrical steel strips.

7. The method according to claim 6 , wherein a rolling force applied to the pair of upper and lower feed rolls is controlled within a range of more than or equal to 1000 N and less than or equal to 2500 N.

8. The method according to claim 1 , wherein a rolling force applied to the pair of upper and lower feed rolls is controlled within a range of more than or equal to 1000 N and less than or equal to 2500 N.

Assignees

• Jfe Steel Corp

Inventors

• Senda Kunihiro
• Uesaka Masanori
• Oda Yoshihiko

Classifications

• B21D28/22 Primary

  Notching the peripheries of circular blanks, e.g. laminations for dynamo-electric machines · CPC title

• H01F41/024

  Manufacturing of magnetic circuits made from deformed sheets (magnetic cores made from deformed sheets H01F27/2455) · CPC title

• Y10T29/49078

  Laminated · CPC title

• H02K15/02

  of stator or rotor bodies · CPC title

• B21D28/02

  Punching blanks or articles with or without obtaining scrap (cutting nails or pins from strips or sheet material B21G3/26); Notching · CPC title