Abstract: An apparatus and system for improving the contact between the heads of a disk drive and the storage media of the disk by improving disk stability. The apparatus comprises a disk having a disk stability pattern disposed proximate a center region of the disk. The disk stability pattern improves disk stability by reducing vibration modes in the spinning disk, thereby minimizing the formation of standing waves in the spinning disk media, and by improving disk compliance, thereby minimizing disk anisotropic curl and tilt.

Abstract: A system for monitoring and controlling the length of anchor rode comprises a winch, a sensor assembly associated with the winch and a control circuit connected to the sensor and the winch. The winch is mounted on a vessel and has a rotatable element about which a length of anchor rode is at least partially wrapped. The sensor assembly is mounted adjacent the rotatable element for generating signals representative of the amount and direction of rotation of the rotatable element. The winch is controllable to rotate the rotatable element in a first direction, either in a powered fashion or through free fall, for letting out the anchor rode from the vessel to lower the anchor. The winch is also controllable to rotate the rotatable element in a second direction for pulling the anchor rode into the vessel to raise the anchor.

Abstract: A belt-driven tape cartridge having more internal tape storage capacity than prior art cartridges adhering to a standard, but having the same outside dimensions as such a standard cartridge. The invention optimizes internal tape storage capacity in a approximately standard quarter inch cartridge by optimizing the geometric configuration and placement of internal tape guide rollers, repositioning internal side walls, and optimizing the size of the tape drive roller. Compared to the standard, the tape guide rollers are reduced in diameter and moved further away from the center line of the tape reels. Also in comparison to the standard, the side walls are also repositioned further away from the radial center of the tape reels. Optionally, the drive interface portion of the belt drive roller is decreased in size, while the required linear velocity of the tape is maintained by proportionally decreasing the radius of the belt interface portion of the belt drive roller.

Abstract: A highly durable, usually hydrolytically stable, drive belt for belt-driven tape cartridges is disclosed which is a thin continuous flexible loop of at least one polyetherurethane (preferably non-hygroscopic), which is both durable and strong. Preferably the belt will be composed of a composite of two separate polyetherurethane materials, one having a higher molecular weight and longer polymer chain length than the other. Also preferably, these two polyetherurethane materials will be blended to a homogenous mixture by melting both materials and blend the molten material and forming the belt from the resulting polymeric mixture. Optionally a single polyetherurethane polymer may be used as the material comprising the belt if that single material has the requisite properties of flexibility and durability.

Abstract: The tape guidance system includes at least three tape guidance surfaces, each of the tape guidance surfaces having at least one enlarged shoulder extending from the tape guidance surface toward the tape to bear upon an edge of the tape and provide a confinement force parallel to the plane of the tape in a direction transverse to the direction of the tape motion. Two adjacent tape guide surfaces have a close tolerance guide, with a distance between the shoulders being equal to or slightly greater than the width of the tape. The third tape guidance surface has a wide clearance such that if the tape is to contact the shoulder of the third guide, it must deviate from a straight line path. The tape has a tendency toward the shoulder of the third guide as a function of the perpendicularity of the tape guide to the plane of the tape. The tape path is such that if a tape is to contact the shoudler of the third guide it must contact alternature surfaces of the other two guides.

Abstract: A tape spool for use in a magnetic tape cartridge which includes means for maintaining the spool at a predetermined height relative to the cartridge base in order to stabilize the tape path. The spool is adapted for mounting on and rotation relative to a cylindrical pin extending perpendicularly from a base toward an opposite wall, the base and wall defining opposite substantially parallel sides of an enclosure, the tape spool remaining a constant distance from the base and including: a hub having a central aperture for mounting on the pin, an upper surface, a lower bearing surface, and a circumferential tape supporting rim; a disc attached to the hub; a spring formed in the disc and in contact with the upper surface of the hub; and a central aperture for mounting on the pin; and a retaining member adjacent the upper portion of the disc, the spring urging the disc against the retaining member and simultaneously urging the hub downward such that the hub is retained at a constant distance from the base.

Abstract: A fastening system or mechanism for fastening a cover member of a first, resilient material to a base member of a second, relatively rigid material to form a tape cartridge housing comprises a single rigid fastener connected between the base and cover members and at least one expansion or slip fastener rigidly connected to one of the members and loosely connected to the other member in a manner permitting a predetermined degree of relative sliding movement between the members in any direction in the plane parallel to the base and cover members, while restricting perpendicular movement between the members. In the preferred embodiment, the expansion fastener comprises a headed post or screw extending through an enlarged opening in one of the members with some free play and fastened in an opposing bore in the other member.

Abstract: A magnetic head, and method of its construction, for placing multiple, high tolerance servo information tracks in evenly spaced configuration across the width of a magnetic medium in a single pass of the magnetic head over the medium. The head comprises a monitoring fixture which secures a full-width write transducer, in tandem with a multiple-track write transducer. Preferably, the transducers are angularly skewed with respect to the travel direction of the magnetic medium, but are substantially parallel to each other. In operation, the magnetic medium first passes adjacent the full-width write transducer which writes a servo pattern across the width of the magnetic medium at a first frequency. The magnetic medium next passes adjacent the multiple-track write transducer which writes servo information onto multiple tracks in the magnetic medium at a second frequency.

Abstract: A magnetic recording system including a write head comprising a write transducer having a gap configured at an angular orientation with respect to direction of travel of an adjacent magnetic medium. Servo information is recorded by the write head into a servo, or higher coercivity, layer of the magnetic medium in a plurality of parallel, adjacent tracks and at an angle corresponding to the angular orientation of the write transducer. The servo information is at one of two frequencies, with adjacent tracks being at different frequencies with respect to each other. A read head includes a first transducer configured at an orientation corresponding to the angular orientation of the servo information. The first transducer and its related circuitry detect information from the parallel servo tracks, and generate an error signal indicating actual position of the second transducer as compared to its desired position with respect to the servo tracks.