Spindle motor and hard disk drive therewith

A spindle motor comprising:

• a rotating part;
• a rotor magnet arranged at the rotating part;
• and
• a stator core arranged at a distance from the rotor magnet so as to form a gap in a radial direction therefrom, the stator core including plural sheet-shaped components made of a magnetic material which are laminated and which have an annular body with a circumferential edge provided with plural teeth portions to be wound with a coil;
• wherein the sheet-shaped components are joined by a swaging portion that is formed by recessing one side thereof so as to project to the other side, the sheet-shaped components have a thickness of not less than 0.1 mm and not more than 0.2 mm, the swaging portion when viewed from an axial direction has an approximately rectangular shape with short sides and long sides, the long sides extending along the tooth portion, a cross section of the swaging portion when viewed from a circumferential direction has a middle portion parallel to the radial direction and has a slope portion between the middle portion and each of the short sides, the recess of the swaging portion has a depth that is less than the thickness of the sheet-shaped component whereby the sheet-shaped component is not cut at the swaging portion, wherein the rotor magnet has a height of not less than 1.5 mm and not more than 2.5 mm, the stator core has a height of not less than 0.6 mm and not more than 1.4 mm, and the gap in the radial direction between the rotor magnet and the stator core is not less than 0.20 mm and not more than 0.25 mm.

A spindle motor comprising:

• a rotating part;
• a rotor magnet arranged at the rotating part;
• and
• a stator core arranged at a distance from the rotor magnet so as to form a gap in a radial direction therefrom, the stator core including plural sheet-shaped components made of a magnetic material which are laminated and which have an annular body with a circumferential edge provided with plural teeth portions to be wound with a coil;
• wherein the sheet-shaped components are joined by a swaging portion that is formed by recessing one side thereof so as to project to the other side, the sheet-shaped components have a thickness of not less than 0.1 mm and not more than 0.2 mm, the swaging portion when viewed from an axial direction has an approximately rectangular shape with short sides and long sides, the long sides extending along the tooth portion, a cross section of the swaging portion when viewed from a circumferential direction has a middle portion parallel to the radial direction and has a slope portion between the middle portion and each of the short sides, the recess of the swaging portion has a depth that is less than the thickness of the sheet-shaped component whereby the sheet-shaped component is not cut at the swaging portion, wherein the coil has a wire diameter of not less than 0.10 mm and not more than 0.13 mm and is wound not less than 40 times and not more than 75 times.