Abstract: A system and method for analyzing a coil actuator of a type having a coil and a magnet. A current source selectively applies a first current to a coil of a coil actuator for setting a moveable part of the coil actuator to a first position. A recording system captures data corresponding to a back electromotive force voltage produced by oscillation of the coil actuator upon movement of the moveable part of the coil actuator to a second position. A processor applies a curve fit to the back electromotive force data for calculating a frequency characteristic and damping response of the coil actuator.

Abstract: The invention is a non-contact optical tape tension sensor for a tape drive. A light source directs an incident beam to the tape in a region of the tape path near where the tape bends. The amount of divergence of the reflected light is related to the curvature of the tape, and thus to the tape tension. The reflected light is passed through an aperture to a photodetector that detects the amount of the divergent beam passing through the aperture. The photodetector output is input to the tape drive controller that controls the currents to the supply and take-up motors to thereby maintain the tape tension within the desired range.

Abstract: The invention is a non-contact optical tape tension sensor for a tape drive. A light source directs an incident beam to the tape in a region of the tape path near where the tape bends. The amount of divergence of the reflected light is related to the curvature of the tape, and thus to the tape tension. The reflected light is passed through an aperture to a photodetector that detects the amount of the divergent beam passing through the aperture. The photodetector output is input to the tape drive controller that controls the currents to the supply and take-up motors to thereby maintain the tape tension within the desired range.

Abstract: A high torsional stiffness low axial deflection stiffness flexible drive shaft apparatus is provided for driving a magnetic tape cassette and includes a drive shaft having opposite ends, a device for engaging the magnetic tape cassette and a pair of flexible diaphragms. A device is connected to one of the drive shaft ends, one of the flexible diaphragms, and is connectable to a motor for transmitting torsional force from the motor to the drive shaft via the flexible diaphragm. Another device is connected to the other end of the drive shaft, the other flexible diaphragm and the tape cassette engaging device for transmitting torsional force from the drive shaft to the engaging device via the other flexible diaphragm.

Abstract: A high torsional stiffness low axial deflection stiffness flexible drive shaft apparatus is provided for driving a magnetic tape cassette and includes a drive shaft having opposite ends, a device for engaging the magnetic tape cassette and a pair of flexible diaphragms. A device is connected to one of the drive shaft ends, one of the flexible diaphragms, and is connectable to a motor for transmitting torsional force from the motor to the drive shaft via the flexible diaphragm. Another device is connected to the other end of the drive shaft, the other flexible diaphragm and the tape cassette engaging device for transmitting torsional force from the drive shaft to the engaging device via the other flexible diaphragm.

Abstract: A tape reel brake which is mounted in a well in the top of a tape reel hub. The well is inside the tape bearing surface of the hub. The brake is mounted to be compliantly biased away from the base of the well. The hub is seated against a first inside surface of a tape cartridge housing. The hub and brake are seated in the tape cartridge such that teeth on the periphery of the brake are biased against the opposite inside surface of the cartridge housing about the periphery of an opening therein. The biasing of the brake against the opposite inside surface both prevents the rotation of the reel and shields out dust when the tape cartridge is removed from a tape drive. To rotate the reel, a tape drive clutch enters the opening in the opposite inside surface and depresses the brake into the well to mate with a smaller diameter portion of the hub or a recessed portion of the brake.

Abstract: The invention is a constrained pivot compound radius tape post guide. The post is mounted on an axle which allows it to pivot when the tape changes direction. The pivoting action serves to peel away all tape which has been in stationary contact with the post, thereby reducing startup stiction. Above a certain rotation angle the post is prevented from further rotation either by a fixed stop or by torque exerted on the post by the tape which is under tension.

Abstract: The invention is a tape guiding post including a tape engaging surface having a longitudinal contour with a compound radius of curvature. In the preferred embodiment, the longitudinal contour has a smoothly varying radius of curvature. The outer portions of the contour have a relatively large radius of curvature and blend smoothly into a central portion which is of a relatively small radius of curvature to allow for any desired bending of the tape in its easy direction. The combination minimizes both friction and stiction between the tape and the guide. The guide is also laterally contoured to accommodate droop at the edges of the tape, caused by low air pressure at the edges.

Abstract: A gimbaled compliant guide for tape drives includes two plates mounted adjacent opposite edges of an arcuate tape bearing surface. The plates are pivotably mounted to accommodate variances in the tape path resulting from tape path tolerances and tape distortions. One plate is also mounted to a leaf spring to accommodate variations in tape width. The combination of simple compliancy and the ability to pivot eliminates the concentration of the stress at a single contact point between the tape edge and the guiding mechanism. By evenly distributing the stress along the span of contact between the edge of the tape and the guides, particulate matter generated from such contact is minimized. Such guiding mechanism may be used on any element of the tape path.

Abstract: A parabolic trough solar collector using reflective flexible materials is disclosed. A parabolic cylinder mirror is formed by stretching a flexible reflecting material between two parabolic end formers. The formers are held in place by a spreader bar. The resulting mirror is made to track the sun, focusing the sun's rays on a receiver tube. The ends of the reflective material are attached by glue or other suitable means to attachment straps. The flexible mirror is then attached to the formers. The attachment straps are mounted in brackets and tensioned by tightening associated nuts on the ends of the attachment straps. This serves both to stretch the flexible material orthogonal to the receiver tube and to hold the flexible material on the formers. The flexible mirror is stretched in the direction of the receiver tube by adjusting tensioning nuts.

Abstract: A conduction heat transfer connection is made between a heat source and a heat sink which is flexible so as to adapt to variations in distance between the source and sink and which maintains the required force on the heat source to obtain the required heat transfer across the junction therebetween. The connection consists of a heat conductive metallic foil bundle of sufficient thickness to contact sufficient surface area of the heat source to provide the required heat transfer and of sufficient thinness to be flexible enough to absorb the expansion and contraction due to temperature changes as well as the differences in distance between the heat source and sink and of sufficient length to contact at or near the other end thereof the heat sink.