Stacked stator core and production method therefor and rotary motor and production method therefor

A stacked stator core, comprising:

• a plurality of stator cores, each of which is made up of a prescribed number of stacked sheet magnetic materials;
• a plurality of yoke members forming each stator core;
• a bendable bent portion provided between said yoke members;
• and
• an interconnecting portion for interconnecting said plurality of stator cores by connecting the upper end of one stator core to the lower end of the other stator core with a difference in level provided between said plurality of stator cores.

A stacked stator core, comprising:

• a plurality of stator cores, each making up of a prescribed number of stacked sheet magnetic materials;
• a plurality of yoke-members forming each stator core;
• a bendable bent portion provided between said yoke members;
• and
• a connecting member, provided between the upper end of one stator core and the lower end of the other stator core, for interconnecting said plurality of stator cores.

A rotary motor, comprising:

• a stator connected both ends of the stator core by bending a stator core in a ring having a plurality of stator cores, each making up of a prescribed number of stacked sheet magnetic materials;
• a plurality of yoke members forming each stator core;
• a bendable bent portion provided between said yoke members;
• and an interconnecting portion for interconnecting said plurality of stator cores by connecting the upper end of one said stator core to the lower end of the other stator core with a difference in level provided between said plurality of stator cores;
• and
• a base equipped with said stator.

A rotary motor, comprising:

• a stator core having a plurality of yoke members, each yoke member making up of a prescribed number of stacked sheet magnetic materials;
• a bendable bent portion provided between said yoke members;
• a stepped yoke member whose one part of said yoke members is shifted from the other yoke members in the stacking direction of said sheet magnetic materials relative to another yoke member;
• a stator formed by bending said stator core in a ring and connected both ends of said stator core;
• and
• a base equipped with said stator.

A rotary motor, comprising:

• a plurality of stator cores, each stator core making up of a prescribed number of stacked sheet magnetic materials;
• a plurality of yoke members forming each stator core;
• and
• a bendable bent portion provided between said yoke members,
• wherein the electric angle θb between the ends of two adjacent magnetic pole teeth out of a plurality of magnetic pole teeth provided on each yoke member and the center of said stator core arranged in a ring, and the electric angle θ between the center of said bent portion and the end of magnetic pole tooth adjacent to said bent portion and the center of said stator core arranged in a ring satisfy the relationships of θb−10°≦θ≦θb+10° and θ≠θb.

A disk drive unit, comprising:

• a stator core divided from a stacked stator core provided with a plurality of stator cores, each stator core making up of a prescribed number of stacked sheet magnetic materials;
• a plurality of yoke members forming each stator core;
• bendable bent portion provided between said yoke members;
• an interconnecting portion for interconnecting said plurality of stator cores by connecting the top of one stator core to the bottom of the other stator core with a difference in level provided between said plurality of stator cores;
• and
• a portion for reading and writing data from and to magnetic recording media rotated by said rotary motor.

A disk drive unit, comprising:

• a plurality of yoke members, each yoke member making up of a prescribed number of stacked sheet magnetic materials;
• a bendable bent portion provided between said yoke members;
• a stator core provided with a stepped yoke member whose one part is shifted by a prescribed number in the stacking direction of said plate magnetic materials relative to another yoke member;
• a stator formed by bending said stator core in a ring and connected both ends of said stator core;
• a base equipped with said stator;
• and
• a portion for reading and writing data from and to magnetic recording media rotated by said rotary motor.

A method of manufacturing a stacked stator core, comprising the steps of:

• stacking a prescribed number of ring-shaped sheet magnetic materials provided with a plurality of yoke members and having a first divided portion at one place between said yoke members and a bent portion at the other place therebetween, such that each first divided portion is placed at the same position;
• stacking a prescribed number of sheet magnetic materials such that second divided portions thereof are placed with a prescribed number shifted by a unit of yoke members in the circumferential direction relative to said prescribed number of stacked sheet magnetic materials;
• and.
• successively stacking said sheet magnetic materials to form a stacked stator core by repeating said two steps as many as a desired number of times.

A method of manufacturing a stacked stator core, comprising the steps of:

• stacking a prescribed number of ring-shaped sheet magnetic materials provided with a plurality of yoke members and having bent portions provided between said yoke members and a first divided portion in the vicinity of one said bent portion, such that each first divided portion is placed at the same position;
• stacking a prescribed number of sheet magnetic materials having a second divided portion at the position opposed to said first divided portion through said bent portion on said stacked sheet magnetic materials, such that each second divided portion is placed at the same position;
• stacking a prescribed number of sheet magnetic materials such that third divided portions thereof are placed with a prescribed number shifted by a unit of yoke members in the circumferential direction relative to the prescribed number of stacked sheet magnetic materials having the second divided portion;
• and
• successively stacking said sheet magnetic materials to form a stacked stator core by repeating said three steps a prescribed number of times.

A method of manufacturing a rotary motor, comprising the steps of:

• stacking a prescribed number of ring-shaped sheet magnetic materials provided with a plurality of yoke members and having a first divided portion at one place between said yoke members and a bent portion at the other place therebetween, such that each first divided portion is placed at the same position;
• stacking a prescribed number of sheet magnetic materials such that second divided portions thereof are placed with a prescribed number shifted by a unit of yoke members in the circumferential direction relative to said prescribed number of stacked sheet magnetic materials;
• successively stacking said sheet magnetic materials to form a stacked stator core by repeating said two steps as many as a desired number of times;
• elongating the bent portions of said stacked stator core to unfold said stacked stator core straight;
• winding driving coils around said magnetic pole teeth provided on said yoke members;
• dividing said wound yoke members into stator blocks;
• and
• forming a ring-shaped stator by bending said divided stator at said bending portion and connecting both ends thereof.

A method of manufacturing a rotary motor, comprising the steps of:

• stacking a prescribed number of ring-shaped sheet magnetic materials provided with a plurality of yoke members and having a bent portion between said yoke members and a first divided portion in the vicinity of one said bent portion, such that each first divided portion is placed at the same position;
• stacking a prescribed number of sheet magnetic materials having a second divided portion at the position opposed to said first divided portion through said bent portion on said stacked sheet magnetic materials, such that each second divided portion is placed at the same position;
• stacking a prescribed number of sheet magnetic materials such that third divided portions thereof are positioned with a prescribed number shifted by a unit of yoke members in the circumferential direction relative to the prescribed number of stacked sheet magnetic materials having the second divided portion;
• successively stacking said sheet magnetic materials to form a stacked stator core by repeating said three steps as many as a desired number of times.
• elongating the bent portions of said stacked stator core to unfold said stacked stator core straight;
• winding driving coils around said magnetic pole teeth provided on said yoke members;
• dividing said wound yoke members into stator blocks;
• and
• forming a ring-shaped stator by bending said divided stator at said bending portion and connecting both ends thereof.