Armature core

An armature comprising:

• a plurality of core sheets each having a plurality of slots, a plurality of punched-in recesses formed on a bottom surface of each core sheet and a plurality of punched-out protrusions formed on a top surface of each core sheet by punching in said plurality of punched-in recesses, both said protrusions and said recesses being formed by press-working;
• said plurality of core sheets being laminated by press-fitting said plurality core sheets together by respectively inserting aid plurality of punched-in protrusions arranged on said top surface of each core sheet into said plurality of punched-in recesses arranged on said bottom surface of a contiguous core sheet thereby positioning and integrally laminating said plurality of core sheets;
• and
• wherein said plurality of punched-out protrusions and said plurality of punched-in recesses of each core sheet are formed such that said plurality of punched-out protrusions substantially fit into said plurality of punched-in recesses so that in press-fitting said plurality of punched-out protrusions of a first core sheet into said plurality of punched-in recesses of a second core sheet contiguous to said first core sheet a very small clearance is provided between contiguous core sheets.

An armature comprising:

• a plurality of core sheets each having a plurality of slots, a plurality of punched-in recesses formed on a bottom surface of each core sheet and a plurality of punched-out protrusions formed on a top surface of each core sheet by punching in said plurality of punched-in recesses, both said protrusions and said recesses being formed by press-working;
• said plurality of core sheets being laminated by press-fitting said plurality of core sheets together by respectively inserting said plurality of punched-out protrusions on said top surface of each core sheet into said plurality of punched-in recesses arranged on said bottom surface of a contiguous core sheet thereby positioning and integrally laminating said plurality of core sheets;
• and
• wherein a height of each of said protrusions is larger than a depth of each of said recesses thereby providing a very small clearance between two contiguous core sheets.