Magnetic disc memory

Claim 1

A magnetic disc memory comprising a plurality of circular magnetic storage discs which are arranged axially spaced from one another on a shaft directed at right angles to the disc plane, a first drive means to drive the shaft, a plurality of swivel arms mounting a plurality of magnetic heads to record and play back information onto or from the magnetic storage discs, the heads including means for dynamic air-spacing from the discs responsive to high speed disc rotation, means pivotally mounting the swivel arms on a pivot for common swivel movement about an axis spaced from and substantially parallel to the shaft axis, so that a swivel arm can be swung in an arcuate path across the disc plane immediately adjacent thereto to position said magnetic heads between two adjacent magnetic storage discs to record and play back information on various tracks thereon, and a second drive means to swing the swivel arms, each of said swivel arms over the portion thereof which extends into the region adjacent the storage discs being constructed of spaced apart upper and lower planar walls of rigid material which extend parallel to one another and to the disc planes, said spaced apart walls being joined at the leading edge thereof by a semicircular wall portion and being joined at the trailing edge thereof by a wall portion to produce a hollow, lightweight body having a symmetrical aerodynamic surface thereby to minimize the weight and air resistance of said portion, the spacing between said upper and lower planar walls being reduced to substantially zero over the terminal end portions thereof remote from said pivot, and means securing the magnetic heads to the respective swivel arms at the terminal ends thereof opposite the pivot.