One aspect of the invention relates to an apparatus and method for retaining a disc drive head disk assembly (HDA) during a servo track writing procedure. The HDA includes a base, a disc stack coupled to a spindle rotatably attached to the base by a spindle shaft, and an actuator assembly pivotally attached to the base at a pivot shaft. Attached to one end of the actuator assembly proximal the disc stack is one or more transducers for reading/writing information from/to the discs. In one embodiment, the method includes restraining the ends of the spindle shaft and pivot shaft during servo track writing so that relative deflection therebetween is minimized. That is, all but rotational motion of the components is substantially eliminated. An apparatus for restraining the ends of the spindle shaft and pivot shaft is also provided. By so restraining the shaft and spindle, the servo information written by the transducers is concentric to the rotation of the disk, reducing track misregistration and improving maximum track density.

A servo track writer for a head disk assembly and a method of making the head disk assembly using the servo track writer are disclosed. The head disk assembly includes an enclosure having an opening and a base and an actuator arm coupled to the base and having a servo writer positioning arm facing surface. The servo track writer includes a platform for supporting the head disk assembly. The platform includes a base portion, a column extending substantially perpendicular to the base portion, and an elongated servo writer positioning arm for protruding through the opening and supported by the column. The positioning arm includes a main body, a tip having an actuator arm facing surface for abutting the positioning arm facing surface, and a vibration damper positioned between the main body and the tip. The vibration damper damps vibrations induced in the actuator arm by dissipating energy transferred between the platform and the actuator arm.

A method and apparatus for originally recording servo information on a disk surface. The apparatus comprises a servo writer assembly which includes an optical encoder having a movable input member and means for producing an output signal which indicates small uniform units of movement of said input member. The servo writer assembly is detachably mounted to a disk storage system with the optical encoder input member tightly physically coupled to the head arm of the storage system head disk assembly. During servo writing, the optical encoder output signal is connected in a closed servo loop with the head positioner motor so that the positioner motor can then be operated to precisely radially increment the servo head, track by track, over the disk servo surface.

Releasable connectors are disclosed for attaching a servo writing fixture to a head transducer assembly to facilitate writing servo information on a servo surface of a rigid disk drive. One connector includes a body for support and attachment of the fixture and an engagement collet for attachment to the top arm of the transducer arm assembly. The engagement collet has a spring operated internal mandrel which disengages the collet from the transducer assembly. Alignment is accomplished with a registration pin that attaches to the top arm of the arm assembly. The second connector includes two parts that are hinge connected in the middle and spring biased apart at the top to form a clamping mechanism. The completed hinged connector defines three leg extensions for attachment to the side of the top arm of the arm assembly and alignment in an opening in the top arm of the arm assembly. Release of the second connector occurs upon compression of the spring. The invention finds special application for attaching and aligning a laser beam retroreflector to the arm assembly to be used in conjunction with a laser interferometer to accomplish servo writing operations on a plurality of disks. The invention is adaptable for use with robotics.

An improved magnetic read/write head-positioning apparatus including a cantilevered lead screw head carriage-driving mechanism and a damping assembly for damping any transverse motion of the unsupported end of the lead screw. The damping assembly includes a leaf spring having one end affixed to the supporting frame and the other end positioned opposite the unsupported end of the lead screw, and a slider button disposed between the leaf spring and the unsupported lead screw end and carried by the lead screw so as to frictionally engage the leaf spring and cause a force to be exerted on the unsupported lead screw end tending to resist any transverse motion thereof.