Abstract: Helical scan tape recorder/playback apparatus includes a pair of concave air-bearing surfaces disposed immediately adjacent and tangential to opposing sides of a circumferential surface of a rotary head scanner, to cooperatively form a path for guiding magnetic tape past the head scanner at a predetermined angle other than zero degrees. A vacuum source serves to evacuate air from the vicinity of each air-bearing surface to create an air pressure gradient the effect of which is to cause magnetic tape to ride on a thin film of air interposed between the tape and each air-bearing surface during transport of the tape from a supply reel to a take-up reel.

Abstract: A reel assembly apparatus for coaxial magnetic tape reels is provided in which both an inboard reel and an outboard reel may be reliably clamped to their respective drive spindles from the outboard side of the assembly apparatus with ease and convenience. For the purpose of clamping the inboard reel, an internal locking nut extends radially in the plane of the inboard reel from its drive spindle into threading engagement with a hub of the inboard reel. A linkage, extending axially through the outboard drive spindle, rotates in response to turning movement of a bail accessible to an operator. The locking nut, in response to the rotation of the linkage, (1) initially causes the inboard hub to rotate, relative to the inboard reel, a limited amount into a reel-clamping position, and (2) then causes an axial movement of the inboard hub. This latter movement drives the inboard reel axially, to clamp it against a radially extending member of the inboard drive spindle.

Abstract: A tape guide mechanism includes an edge-guide element extending radially from a central axis. A tape guide roller, rotatable about the central axis, is arranged for urging an advancing magnetic tape laterally in the direction of the edge-guide element, to maintain an edge of the tape perpendicular to and in continuous contact with the edge-guide element during tape transport movement. A piezoelectric actuator, preferably comprising a stack of flexing type bimorph elements responsive to a voltage signal relating to the direction and magnitude of a tape-tracking error, causes movement of the edge-guide element in a single composite direction having a first component which is perpendicular to the edge of the tape, and a second component, which is parallel to the tape edge.

Abstract: Methods and apparatus for transferring information relative to a recording medium bend the medium about a first axis and move an information transfer stimulus in an arc over such bent medium about a second axis laterally offset from and extending at an angle to the first axis. These methods and apparatus impart to the bent medium a wave-shaped configuration for accommodating the mentioned arc in a perpendicular plane through the second axis. The wave-shaped configuration may be imparted to the medium with the aid of a guide or roller having a wave-shaped contour.

Abstract: Method and apparatus for advancing tape having an information recording surface relative to an information transducing head provide a sliding surface at a distance from the head, preferably paralleling a tape advance path in a transducing mode in which the tape moves with its information recording surface in engagement with the transducing head. For a fast tape advance mode, such as rapid rewind or fast forward, the tape is moved to the sliding surface away from the head. Preferably, the tape is so moved with the aid of a pressure gradient generated on a surface of the tape opposite its recording surface. The tape is then advanced along the sliding surface in the fast tape advance mode in spaced relationship to the transducing head, while preferably being maintained with the pressure gradient on the sliding surface for the duration of the particular fast tape advance.

Abstract: Methods and apparatus for advancing tape relative to an information transducing head with the aid of a tape drive capstan employ a first vacuum column at the tape drive capstan and a second vacuum column remote from the capstan. The tape is applied to the capstan and to the vacuum columns and is advanced with the capstan through the vacuum columns and in information transducing relationship with the head in an information transducing mode. The tape is removed from the first vacuum column and is disengaged from the capstan for a fast tape advance mode, while being retained in the second vacuum column. The tape is advanced in the fast tape advance mode only through the second column, and the fast tape advance mode is controlled with the second vacuum column.

Abstract: Methods and apparatus for guiding an advancing tape in either one of two opposite directions employ a hollow tape guide member, a post through such hollow tape guide member, a sleeve around such post inside the hollow tape guide member, and a tape guide surface at an end of the tape guide member peripherally thereof and at an angle thereto. A fulcrum extends circumferentially around the post at a predetermined location offset in a direction away from the tape guide surface from a central location corresponding to a longitudinal center line of the tape, for supporting the sleeve for omnidirectional tilting motion relative to a plane intersecting the post at the predetermined location. The hollow tape guide member is mounted on the sleeve with spaced bearings located at opposite sides of the mentioned plane, for rotation about the post and tilting motion with the sleeve.

Abstract: A hollow-cylindrical member, such as a reel, is releasably retained on a rotatable hub against forces tending to loosen the reel. To this end, a plurality of locking keys are inserted into corresponding axial slots in the reel at the inside thereof. These locking keys are first driven up corresponding ramps on the hub into engagement with the inside of the reel at corresponding slots. After such engagement, and during rotation of the hub and reel, the locking keys are continously biased or further urged into their corresponding slots in order to inhibit any looseness between the releasably retained reel and the rotating hub. By way of example, tape reels of large size and mass may thus be securely retained against strong inertial forces occasioned particularly during rapid reversals of the reel rotation as occurring, for instance, in modern instrumentation tape recording and data processing machines.

Abstract: Tape guiding methods and apparatus advance a tape through an arcuate bend having equal radii at both edges. Within that bend an unbalance providing a net force transversely of the tape is created at the tape edges while maintaining the equal radii. The advancing tape is guided by applying it with the created net force to a reference surface while maintaining the equal radii.

Abstract: A tape guide has a tape supporting surface extending across a major surface of an advancing tape at a supporting region extending from a tape touchdown region to a tape liftoff region. The tape guide stresses the advancing tape with the tape supporting surface uniformly across the tape and at both tape edges. A reference surface extends at an acute angle to the supporting surface between and exclusive of the tape touchdown and liftoff regions in order to position the advancing tape at one of its tape edges.

Abstract: A metallic mass is placed into frictional engagement with a transducer head structure. Vibrations of such transducer head structure are dampened by relative displacement between the metallic mass and frictionally engaged transducer head structure. Plastic deformation of the metallic mass frictionally engaging the transducer head structure may also be employed to dampen vibrations. The metallic mass may be pressed into frictional engagement with the transducer head structure, and vibrations from the frictionally engaged transducer head structure may be transmitted through the metallic mass to the viscoelastic polymeric layer to set up shearing strains in that layer causing the mass to dampen vibrations of the transducer head structure by lagging oscillation in frictional engagement with that transducer head structure.

Abstract: Methods and apparatus for advancing a tape with a tape capstan rotating about an axis provide the capstan with circumferential grooves distributed across the capstan and withdraw air from each groove for attracting the tape to the capstan. The tape is guided to a first peripheral capstan region extending across the capstan and is shieleded against the withdrawal of air in each groove during such guiding to the first peripheral capstan region. The tape is attracted to the capstan by the withdrawal of air in each groove at the first peripheral capstan region and is advanced with the rotating capstan through an arc to a second peripheral capstan region extending across the capstan, while being maintained attracted to the capstan by withdrawal of air from each groove. The tape is released from the capstan at the second peripheral capstan region, is guided away from the capstan and is shielded against withdrawal of air in each groove during such guiding away from the capstan.

Abstract: A belt driven tape cartridge employs a pair of tape reels on fixed spaced axes within a cartridge case and on which a tape extending between them is convolutely wound to form tape rolls. Tape is transported between reels when the reels are driven by a taut belt that extends between the rolls and around a drive roller at one side of a line connecting the tape reel axes and around an idler roller at the other side of that line. The drive roller rotates on a fixed axis which in preferred form is equidistant from the two tape reel axes. The idler roller rotates on an axis that is parallel with the other axes but is free to move laterally.

Abstract: In an endless-roll film cartridge the problem of cyclical variation in film stepping distance (tick-tocking) is overcome by isolating the inertia of the coil of film from the segment of the film loop engaged by the drive claw, and by storing energy in the film segment returning to the coil each time the film is advanced by the claw and then releasing the energy to move the coil preparatory to the next advancement of the film by the claw. Variable blends provide compliance in the film path at opposite ends of the segment engaged by the claw, one of the bends being controlled by a pocket in a guide defining the path of the film segment returning to the coil.

Abstract: In order to advance a sheet-like piece of material, low-friction and high-friction members are provided. These low-friction and high-friction members jointly form a continuous cylindrical surface. The piece is first contacted with the material having the low friction, and is subsequently engaged with the material having the high friction. The piece is then advanced by advancing the material having the high friction.

Abstract: A resiliently deformable low inertia capstan for driving magnetic tape in a digital tape transport is comprised substantially of plastic material having a low elastic modulus and provides substantial rigidity in a circumferential direction as well as accepting substantial deformation in other directions without damage. The capstan includes a rigid inner hub defining a concentric cylinder, a thin-walled cylindrical outer rim disposed concentrically about the inner hub, and a pair of thin-walled, somewhat conical side members interconnecting the hub and rim at opposite ends thereof. Circumferential grooves in the outer surface of the rim improve capstan aerodynamics and a thin coating of polyurethane on the lands of the rim improves the coefficient of friction.