Winchester disc drive actuator structure

Abstract

A Winchester disc spindle construction provides a spindle motor coil wound around laminated formed annular plates and having lead wires extending through a central stationary shaft. Surrounding a spindle coil is a cylinder having a pocket for arcuate permanent magnets. The discs are fixed to and rotated by the cylinder. Relatively large bearings support the cylinder concentric with the shaft and give increased strength to the structure, permitting more discs to be supported in equivalent space, as compared with prior structures. The arms carrying the read-write heads are mounted on a stack of spaced-apart arms pivotted at a distance from the discs so that the heads move along a shallow arc to reduce skewing of the heads relative to the recording tracks of the discs. To reduce overall size of the drive structure (and permit such shallow arc movement) the arm actuator coil is fixed to the arms with its major axis parallel to the pivot axis, as contrasted with prior structures where the major axis of the coil is transverse to the pivot axis. The arms are statically balanced for improved action. A latch to hold the arms stationary when power is off and over-travel limit means are provided.