Driving motor

A motor used for a magnetic disk driving unit, comprising:

• a cup-shaped hub on which a magnetic disk may be mounted;
• a driving magnet attached to an inner peripheral portion of said hub;
• a stator core which is disposed facing said driving magnet and on which a coil is wound around each of a plurality of salient poles thereon, each salient pole having a base side;
• a motor frame securing said stator core;
• a first mounting section provided on said motor frame to mount the neighborhood of the base side of said each salient pole;
• and
• a second mounting section provided on said motor frame to mount an edge side of said each salient pole said second mounting section including, in cross section, an upper portion supporting said pole edges and a lower portion connected with said frame, said upper portion being narrower than said lower portion.

In a disk drive motor having a cup shaped hub including a surface on which a disk may be mounted, a driving magnet attached to an inner peripheral portion of said hub, a stator core which is disposed facing said driving magnet and on which a coil is wound around each of a plurality of salient poles thereon, each salient pole having a base side, a motor frame having a base securing said stator core, and a mounting section provided on said motor frame to mount the neighborhood of the base side of each salient pole, the improvement comprising the following relationships among parts of said motor;

• L<R;
• and
• R=R.sub.1 -R.sub.2
• wherein R.sub.2 represents the radial dimension from a central axis of the motor to the base of a salient pole;
• R.sub.1 represents the radial dimension from the central axis of the motor to the end of a salient pole;
• R represents the length of the salient poles;
• and L represents the dimension from the base of the motor frame to said surface of the hub on which a magnetic disk rests.

A motor, comprising:

• a driving magnet attached to a rotor;
• a stator core which is disposed facing said driving magnet and on which a coil is wound around each of a plurality of salient poles thereon, each salient pole having a base side;
• a motor frame securing said stator core;
• a first mounting section provided on said motor frame to mount the neighborhood of the base side of said each salient pole;
• and
• a second mounting section provided on said motor frame to mount an edge side of said each salient pole, said second mounting section including, in cross section, an upper portion supporting said pole edges and a lower portion connected with said frame, said upper portion being narrower than said lower portion, and
• wherein each salient pole has a through hole on said edge side and said second mounting section has a screw hole for mounting the edge side of each salient pole on the second mounting section using a screw, including a screw mounting the edge side of each salient pole on the second mounting section, said screw being made from a magnetic material.

A motor used for a magnetic disk driving unit, comprising:

• a cup-shaped hub on which a magnetic disk may be mounted;
• a driving magnet attached to an inner peripheral portion of said hub;
• a stator core which is disposed facing said driving magnet and on which a coil is wound around each of a plurality of salient poles thereon, each salient pole having a base side;
• a motor frame securing said stator core;
• a first mounting section provided on said motor frame to mount the neighborhood of the base side of said each salient pole;
• and
• a second mounting section provided on said motor frame to mount an edge side of said each salient pole, said second mounting section including, in cross section, an upper portion supporting said pole edges and a lower portion connected with said frame, said upper portion being narrower than said lower portion, and
• wherein each salient pole has a through hole on said edge side and said second mounting section has a screw hole for mounting the edge side of each salient pole on the second mounting section using a screw, including a screw mounting the edge side of each salient pole on the second mounting section, said screw being made from a magnetic material.

A motor, comprising:

• a driving magnet attached to a rotor;
• a stator core which is disposed facing said driving magnet and on which a coil is wound around each of a plurality of salient poles thereon, each salient pole having a base side;
• a motor frame securing said stator core;
• a first mounting section provided on said motor frame to mount the neighborhood of the base side of said each salient pole;
• and
• a second mounting section provided on said motor frame to mount an edge side of said each salient pole, said second mounting section including, in cross section, an upper portion supporting said pole edges and a lower portion connected with said frame, said upper portion being narrower than said lower portion, and
• wherein each salient pole has a through hole on said edge side for inserting a bush having a screw hole and wherein said second mounting section has a through hole for mounting the edge side of each salient pole on the second mounting section using a screw, including a bush in each salient pole and a screw mounting the edge side of each salient pole on the second mounting section, wherein said bush and screw are made from a magnetic material.

A motor used for a magnetic disk driving unit, comprising:

• a cup-shaped hub on which a magnetic disk may be mounted;
• a driving magnet attached to an inner peripheral portion of said hub;
• a stator core which is disposed facing said driving magnet and on which a coil is wound around each of a plurality of salient poles thereon, each salient pole having a base side;
• a motor frame securing said stator core;
• a first mounting section provided on said motor frame to mount the neighborhood of the base side of said each salient pole;
• and
• a second mounting section provided on said motor frame to mount an edge side of said each salient pole, said second mounting section including, in cross section, an upper portion supporting said pole edges and a lower portion connected with said frame, said upper portion being narrower than said lower portion, and
• wherein each salient pole has a through hole on said edge side for inserting a bush having a screw hole and wherein said second mounting section has a through hole for mounting the edge side of each salient pole on the second mounting section using a screw, including a bush in each salient pole and a screw mounting the edge side of each salient pole on the second mounting section, wherein said bush and screw are made from a magnetic material.