Abstract: A micro-floppy diskette has an outer relatively rigid jacket with a pair of aligned transducer access apertures; an inner containment cup assembly rotatably received within the jacket, the cup assembly including a pair of flexible cups sealed about the periphery and a pair of flexible annular wiping elements secured to the inner surface of each cup member; and a flexible recording disk rotatably received within the cup assembly. The cup members and wiping elements have mutually aligned cut-out portions which expose the disk recording band through the jacket access apertures when the cup assembly is rotated to an open position. When the cup is rotated to a closed position, the recording disk is shielded from ambient by solid portions of the jacket. One of the cup members has a protruding lug arranged in sliding contact with an inner surface of the jacket to bias the disk to a disk operating plane when the cup assembly is in the open position.

Abstract: A miniature flexible magnetic disk assembly having integrally formed motion limit stop projections along the length dimension of the disk assembly enclosure. The projections are formed from either side of the facing major wall portions of the enclosure by intruding a first and second pair of opposed major wall portion projections inwardly of the enclosure. Each projection has a concave outer surface, a convex inner surface and an abutment edge extending into the interior of the enclosure from each end of a progressive cut formed through the major wall portion a sufficient distance to provide an abutment edge forming an interference obstacle to the outer edge of the contained flexible disk.

Abstract: An improved door slide operating mechanism consisting of a door slide with an operated end having a clevis link, a crank having a lower long journal received in a bored boss formed in the bottom portion of a disk cartridge casing and a short upper journal received in a bored boss formed in an upper casing portion, and a spring wound in tension about the lower journal boss and having a free arm biased against an operating end of the crank.The mechanism is easily assembled by winding the spring about the boss, inserting a temporary holding pin into an additional boss formed in the bottom casing to provide a stop for the spring arm, engaging a forked end of a crank arm with the door slide clevis, inserting the long lower journal into its corresponding bore, and removing the temporary pin so that the free spring end bears against a stop provided on the crank arm.

Abstract: A releasable hub locking mechanism for a disk hub assembly and a magnetic memory cartridge. A lever plate having an inner margin with a pair of hub flange pressure portions in surface contact with the lower surface of an inner hub flange arranged within the cartridge housing includes an outer margin with a lower release portion received in an aperture in the bottom portion of the cartridge housing. A longitudinally extending torsion spring has first and second ends secured against rotation by keeper bosses formed in the bottom casing portion and includes a central loop portion for applying a downward pressure to an inwardly extending tang located on the outer margin of the lever plate.The torsion spring normally provides a rotational force to the lever plate to cause the hub to be locked in place by interference between the lower surface of the bottom casing portion and a lower hub flange located externally of the casing.

Abstract: A removable hard disc memory cartridge for use with a drive mechanism including a spindle located within a drive housing.The drive housing interior is provided with stationary position registration members which cooperate with mating side edge portions of the cartridge to provide positive positioning when the cartridge is inserted into the drive housing. A disc lock carried by the cartridge maintains the internally mounted cartridge disc in a secured locked position when the cartridge is not in use, the lock mechanism cooperating with release posts carried by the drive housing to free the disc for rotation just prior to engagement by the drive spindle.

Abstract: A method and apparatus for checking performance and alignment of a disk drive designed for use with a floppy disk having a motor driven linear positioning mechanism for locating the read/write transducer over the diskette circular tracks. A digitally prerecorded diagnostic diskette has a series of precisely located special diagnostic tracks providing reference data for various alignment and response characteristics, both mechanical and electronic. A first group of tracks have sector ID blocks followed by progressively offset data blocks interspersed therein, with the range of the offset greater than the width of the track for which the disk drive is designed, which guarantees a read failure upon reading any track. These tracks are distributed radially across the surface of the diskette at positions corresponding to each rotational phase position of the transducer stepper motor.

Abstract: A holder for removably receiving a plurality of magnetic memory disks and for holding the disks in a vertical stack. The holder includes a base having a center post secured thereto and extending upwardly therefrom. The post is adapted to receive the magnetic disks thereon with the disks being arranged on the posts in generally parallel, horizontal planes and separated from each other by ring-like spacers. A nut is removably mounted on the post for locking the disks in place. The nut has a number of spaced projections on its inner periphery for engagement with spaced, circumferentially extending screw thread segments on the outer surface of the post. The segments are spaced from each other to present recesses for receiving the projections on the nut when the nut is first placed on and moved axially along the post until the nut rests on the uppermost spacer. By rotating the nut through a finite angle, such as 30.degree. to 95.degree.

Abstract: A thermosetting composition for use in the formation of a magnetizable film on a substrate is disclosed herein, which has improved resistance to frictional wear and abrasion, and improved impact durability. The composition comprises a heat-curable polymer resin, magnetizable particles, a fatty ester, and sufficient solvent to provide a viscosity of from about 200 to about 600 centipoise at about 24.degree. C. The method of preparation of the composition as well as its use are also disclosed.

Abstract: Apparatus and a method for positioning a flexible magnetic recording medium, such as a floppy disk, in such a way as to permit magnetic means on opposed sides of the medium to orient the particles in the magnetic coatings on the medium immediately after the coatings have been applied to the medium and as the medium is rotated. In one embodiment, the apparatus includes stabilizing devices which are located at circumferentially spaced locations about the outer periphery of the medium when the medium is mounted for rotation about a generally horizontal axis. Each device comprises a pair of substantially J-shaped, wire-like members secured at first ends to a shaft and presenting second ends which are spaced apart to define a gap between which the outer peripheral margin of the medium passes. The J-shaped members can be tubular or solid. If tubular, they can receive a fluid under pressure from a source coupled with the shaft and direct the fluid onto the opposite sides of the medium as the medium rotates.

Abstract: A magnetic recording medium in the form of a floppy disk having a flexible body formed from a substrate and a magnetic coating on at least one of the two faces of the substrate. The body has a central hole concentric with the central axis of the disk and at least one of the faces of the body is provided with a reinforcing ring of a suitable material capable of being hot stamped, such as foil. The ring is directly bonded by being hot stamped under heat and pressure and without adhesive to the body in surrounding relationship to the hole. A second ring can be provided on the opposite side of the body in surrounding relationship to the hole and directly bonded to the body in the same manner as the first-mentioned ring. The rings can be electrically conductive or non-conductive and out of contact with each other.

Abstract: A stacking device is provided for rigid discs which have an interior aperture. An elongate registry member has cross sectional dimensions slightly less than the interior dimensions of the aperture in the discs. The registry member has a hollow interior and at least six circumferentially spaced axially elongate slots in the outer surface of the member. A pair of sets of elongate rack members are located in the alternating slots in the registry member. Each rack member has a plurality of outwardly directed teeth. The rack members of one set, designated set A, are movable both radially and axially with respect to the registry member. The rack members of the other set, designated set B, are movable radially with respect to the registry member.The sets of rack members of the present invention are operated to load discs in the following fashion. Set A is moved outwardly to receive a disc with set B recessed. Set A moves downwardly carrying the received disc, and set B moves outwardly to receive the disc from set A.

Abstract: Apparatus and method for stacking rigid magnetic discs so that the discs do not come into contact with one another. A hollow elongate member has at least two elongate axial recesses terminating at openings at each end of the recesses. The outer surface of the elongate member has dimensions slightly less than the inner dimensions of the central apertures of the discs. Endless loops are mounted so that the loops traverse the respective recesses and return within the elongate member. Each loop has a plurality of equally spaced nibs projecting outwardly beyond the outer surface of the elongate member. A drive element is located within the elongate member and is attached to each of the loops. The drive member is moved axially within the elongate member to move the loops in unison and thereby allow serial loading and unloading of the discs on sequential nibs. A sensor system may be included to automatically move the loops to space the discs each time a disc is loaded or unloaded.

Abstract: A magnetic coating composition in which magnetic iron oxide particles are dispersed into a solution of three components, which upon evaporation of the solvent and curing with elevated temperatures, results in a very smooth durable polymer coating having the magnetic particles dispersed uniformly therein. The three components in solution are an epoxy resin having an epoxide equivalent weight of approximately 400 or above, a polyamine whch has a minimum of one primary amine group and a cellulose acetate butyrate resin which has approximately 17 weight % butyral content or above. The polyamine, which acts as a catalyst to crosslink the composition, can be substituted for by hydroxyl compounds, a preferred one being formic acid (HCOOH) - an organic acid.

Abstract: An improved flexible magnetic recording disc assembly comprising an envelope and a flexible recording disc rotatably received in the envelope, the disc having an annular reinforcement member concentrically arranged adjacent the central mounting aperture of the disc. Two embodiments are disclosed: a first having a single annular reinforcement member secured to the spindle side of the flexible disc; and a second having a pair of annular reinforcement members disposed on opposite surfaces of the disc. The reinforcement member has an axial thickness in the range from about 2 to about 7 mils to provide sufficient structural rigidity to resist crinkling and flaring during use; a static and dynamic coefficient of friction not less than about 0.3, and a total electrical resistance measured in the longitudinal axial direction in the range of about 1 ohm to about 50 megohms to facilitate dissipation of static electrical charges which may build up on the recording surfaces of the disc.

Abstract: A method and apparatus for treating the recording layer of flexible recording elements to remove protruding agglomerated particles formed during the fabrication process and to provide an extremely smooth surface finish on the order of 1.8AA or less. Several embodiments are disclosed for treating both annular recording discs and roll type recording media. The method comprises burnishing the recording layer surface with a hard smooth abrasive member while supporting the flexible recording element on a resilient backing surface and observing key parameters.