In-situ install of cross-flux magnet in voice coil motor actuator

A voice coil motor produced according to a method comprising:

• creating an opening in a yoke;
• attaching a primary magnet to an inside surface of the yoke;
• installing, through the opening in the yoke, a cross-flux magnet into a channel of the primary magnet to form a cross-flux magnet assembly;
• installing a plug into the opening in the yoke;
• creating an opening in a second yoke;
• attaching a second primary magnet to an inside surface of the second yoke;
• charging the second primary magnet to set opposing magnetization directions on respective sides of a magnetic boundary;
• installing, through the opening in the second yoke, a pre-charged cross-flux magnet into a channel of the second primary magnet to form a second cross-flux magnet assembly;
• installing a plug into the opening in the second yoke;
• and
• coupling the yoke and cross-flux magnet assembly to the second yoke and second cross-flux magnet assembly.

A voice coil motor (VCM) comprising:

• a first yoke comprising an opening therethrough which is filled with a first plug;
• a first primary magnet bonded to the first yoke and having a proximal side adjacent to the first yoke and having an opposing distal side, the first primary magnet configured with opposing magnetic poles having opposing magnetization directions on respective sides of a first boundary;
• a first cross-flux magnet embedded within and bonded to the first primary magnet through the opening in the first yoke and having a proximal side adjacent to the first yoke, the first cross-flux magnet configured with a magnetization direction substantially normal to the magnetization directions of the first primary magnet;
• a second yoke comprising an opening therethrough which is filled with a second plug;
• a second primary magnet bonded to the second yoke and having a proximal side adjacent to the second yoke and having an opposing distal side, the second primary magnet configured with opposing magnetic poles having opposing magnetization directions on respective sides of a second boundary;
• and
• a second cross-flux magnet embedded within and bonded to the second primary magnet through the opening in the second yoke and having a proximal side adjacent to the second yoke, the second cross-flux magnet configured with a magnetization direction substantially normal to the magnetization directions of the second primary magnet.

A hard disk drive (HDD) comprising:

• a plurality of disk media rotatably mounted on a spindle motor;
• a plurality of head sliders each housing a read-write transducer configured to read from and to write to a respective disk medium of the plurality of disk media;
• and
• a voice coil motor (VCM) assembly configured for moving the plurality of head sliders to access portions of the plurality of disk media;
• wherein the VCM assembly comprises:
• a first yoke comprising an opening therethrough which is filled with a first plug composed of a same material as the first yoke,
• a first primary magnet bonded to the first yoke and having a proximal side adjacent to the first yoke and having an opposing distal side, the first primary magnet configured with opposing magnetic poles having opposing magnetization directions on respective sides of a first boundary,
• a first cross-flux magnet embedded within and bonded to the first primary magnet through the opening in the first yoke and having a proximal side adjacent to the first yoke, the first cross-flux magnet configured with a magnetization direction substantially normal to the magnetization directions of the first primary magnet,
• a second yoke comprising an opening therethrough which is filled with a second plug composed of a same material as the second yoke,
• a second primary magnet bonded to the second yoke and having a proximal side adjacent to the second yoke and having an opposing distal side, the second primary magnet configured with opposing magnetic poles having opposing magnetization directions on respective sides of a second boundary, and
• a second cross-flux magnet embedded within and bonded to the second primary magnet through the opening in the second yoke and having a proximal side adjacent to the second yoke, the second cross-flux magnet configured with a magnetization direction substantially normal to the magnetization directions of the second primary magnet.