Abstract: A method for automatically correcting the dynamic imbalance of a disc pack of a disc drive, the disc pack conveyed to a first selected position in a balance correction assembly station where a rotary positioner lifts and rotates the disc pack to a reference position for the attachment of weighted shims to the disc pack. A shim selector assembly delivers a selected shim, and an end effector transfers the selected shim to a shim attachment assembly. The shim attachment assembly rotates and spreads open the shim so that the disc pack can be receivingly engaged thereby, and the shim attachment assembly releases the selected shim to lockingly engage the disc pack. A flipping assembly reverses the disc pack for placement of another selected shim to the other end of the disc pack, as required.

Abstract: A method of automatically measuring the dynamic imbalance of a disc stack of a disc drive assembly, the disc stack conveyed to a first selected position in a balance measure assembly station where a rotary positioner lifts and rotates the disc stack above a sensor to locate an electrical lead of the disc drive motor. The disc stack is positioned in a reference position to position the electrical leads a for powering the disc drive motor. The disc stack is then conveyed to a second selected position where a motor power assembly clamps and powers the motor and discs. A balance head assembly measures the magnitude and phase angle of the dynamic imbalance of the disc stack and records the measurement to a production control computer.

Abstract: An apparatus of automatically measuring the dynamic imbalance of a disc stack of a disc drive assembly, the disc stack conveyed to a first selected position in a balance measure assembly station where a rotary positioner lifts and rotates the disc stack above a sensor to locate an electrical lead of the disc drive motor. The disc stack is positioned in a reference position to position the electrical leads a for powering the disc drive motor. The disc stack is then conveyed to a second selected position where a motor power assembly clamps and powers the motor and discs. A balance head assembly measures the magnitude and phase angle of the dynamic imbalance of the disc stack and records the measurement to a production control computer.

Abstract: An apparatus and method for automatically correcting the dynamic imbalance of a disc pack of a disc drive, the disc pack conveyed to a first selected position in a balance correction assembly station where a rotary positioner lifts and rotates the disc pack to a reference position for the attachment of weighted shims to the disc pack. A shim selector assembly delivers a selected shim, and an end effector transfers the selected shim to a shim attachment assembly. The shim attachment assembly rotates and spreads open the shim so that the disc pack can be receivingly engaged thereby, and the shim attachment assembly releases the selected shim to lockingly engage the disc pack. A flipping assembly reverses the disc pack for placement of another selected shim to the other end of the disc pack, as required.

Abstract: A collet assembly for picking and placing a disc pack in an automated assembly process, the collet assembly having a retractable cylinder that extends to spreadingly engage a segmented collet against a lifting surface of the disc pack to support the disc pack during a lifting operation. The collet assembly is positioned by a positioning assembly to an engaging position adjacent the disc pack. A locking cylinder supports a lower pad and an upper pad on opposing sides of a flange portion of the collet assembly, to provide a fixed mode in a retracted position of the locking cylinder wherein the collet assembly position is fixed relative the positioning assembly, and to provide a compliant mode in an extended position of the locking cylinder wherein the collet assembly is free to compliantly float in a two-axis plane relative to the positioning assembly.