Abstract: A creel threader for use with a creel system that holds a plurality of spools where each spool carries a filamentary material includes a guide supported by the creel, an endless loop carried by the guide, a drive assembly coupled to the endless loop and at least one gripper carried by the endless loop. The gripper receives the filamentary material from at least one of the spools, and the drive assembly moves the gripper and the received filamentary material from the spool to an output end of the creel system for further processing. Related methods of operation are also disclosed.

Abstract: A creel threader for use with a creel system that holds a plurality of spools where each spool carries a filamentary material includes a guide supported by the creel, an endless loop carried by the guide, a drive assembly coupled to the endless loop and at least one gripper carried by the endless loop. The gripper receives the filamentary material from at least one of the spools, and the drive assembly moves the gripper and the received filamentary material from the spool to an output end of the creel system for further processing. Related methods of operation are also disclosed.

Abstract: A disc drive disc stack assembly and a method for forming the disc stack assembly to reduce servo pattern runout. The disc stack assembly includes a number of prewritten discs having a servo pattern and a disc alignment mark. The first step is to place a first disc about a spindle motor hub of the disc drive. The second step is to align a disc alignment mark of the first disc in relation to a direction of a biasing force. The third step is to apply the biasing force to the first disc to engage the first disc against the spindle motor hub. The fourth step is to repeat the first three steps for each remaining disc in the disc stack assembly. The final step is to clamp the prewritten discs with a disc clamp to secure the position of each prewritten disc relative to the spindle motor hub.

Abstract: An apparatus separating a resonance excitation response of a first disc from a resonance excitation response of second disc, the apparatus includes spindle motor with a spindle motor hub supporting the first disc, a disc spacer communicating with the first disc supporting a second disc and a clamp ring attached to this on the motor hub imparting a clamping force on the second disc to form a disc pack. Separation of resonance response between the first disc and the second disc results from maintaining a distinction between an amount of extension of mass and stiffness of each disc available for resonance excitation beyond respective outboard clamping points of the disc spacer. Separation of resonance assures resonance of the first disc is dissipated by a damping of the spindle motor, as well as resonance of the second disc is dissipated by the damping of the spindle motor.

Abstract: An apparatus separating a resonance excitation response of a first disc from a resonance excitation response of second disc, the apparatus includes spindle motor with a spindle motor hub supporting the first disc, a disc spacer communicating with the first disc supporting a second disc and a clamp ring attached to this on the motor hub imparting a clamping force on the second disc to form a disc pack. Separation of resonance response between the first disc and the second disc results from maintaining a distinction between an amount of extension of mass and stiffness of each disc available for resonance excitation beyond respective outboard clamping points of the disc spacer. Separation of resonance assures resonance of the first disc is dissipated by a damping of the spindle motor, as well as resonance of the second disc is dissipated by the damping of the spindle motor.

Abstract: Method for balancing a rotary object, such as a disc drive disc pack. A balance correction member is provided as a C-shaped ring formed from a length of wire of nominally uniform cross-sectional area. The member has a substantially elliptical shape in an uncompressed state. During installation, the amount of imbalance in the disc pack is measured and a member with an appropriate length is selected and compressed to a substantially circular shape. The compressed member is then placed adjacent the disc pack so that the member expands to compressingly engage an annular recess in the disc pack. The member is preferably installed using an automated dynamic balance correction station as part of a high volume disc drive manufacturing environment.

Abstract: Apparatus and method for positioning a head in a disc drive using a dual stage actuator having a primary actuator motor for coarse head positional control and a microactuator motor for fine head positional control. The microactuator motor includes a strain gauge affixed to a piezoelectric transducer measuring actual dimensional change of the microactuator motor resulting from response by the piezoelectric transducer to a request for head repositioning. A closed loop servo control circuit generates control inputs for the dual stage actuator to carry out track following and seek operations while adjusting head position by correcting piezoelectric transducer hysteresis and reducing seek and settle times.

Abstract: A disc drive disc stack assembly and a method for forming the disc stack assembly to reduce servo pattern runout. The disc stack assembly includes a number of prewritten discs having a servo pattern and a disc alignment mark. The first step is to place a first disc about a spindle motor hub of the disc drive. The second step is to align a disc alignment mark of the first disc in relation to a direction of a biasing force. The third step is to apply the biasing force to the first disc to engage the first disc against the spindle motor hub. The fourth step is to repeat the first three steps for each remaining disc in the disc stack assembly. The final step is to clamp the prewritten discs with a disc clamp to secure the position of each prewritten disc relative to the spindle motor hub.

Abstract: Apparatus for balancing a rotary object, such as a disc drive disc pack. A balance correction member is provided as a C-shaped ring formed from a length of wire of nominally uniform cross-sectional area. The member has a substantially elliptical shape in an uncompressed state. During installation, the amount of imbalance in the disc pack is measured and a member with an appropriate length is selected and compressed to a substantially circular shape. The compressed member is then placed adjacent the disc pack so that the member expands to compressingly engage an annular recess in the disc pack. The member is preferably installed using an automated dynamic balance correction station as part of a high volume disc drive manufacturing environment.

Abstract: Apparatus for balancing a rotary object, such as a disc drive disc pack. A balance correction member is provided as a C-shaped ring formed from a length of wire of nominally uniform cross-sectional area. The member has a substantially elliptical shape in an uncompressed state. During installation, the amount of imbalance in the disc pack is measured and a member with an appropriate length is selected and compressed to a substantially circular shape. The compressed member is then placed adjacent the disc pack so that the member expands to compressingly engage an annular recess in the disc pack. The member is preferably installed using an automated dynamic balance correction station as part of a high volume disc drive manufacturing environment.

Abstract: A cold trap assembly having Peltier Junction assembly is provided to reduce the head stiction between a disc drive head and a disc. The Peltier Junction assembly includes a cold region which has a temperature lower than the ambient temperature of the disc drive. Vapors from outgassing components in the disc drive condense on the cold region, thereby reducing the amount of vapors which may condense on the disc surface.