Abstract: A drum assembly (20, 20(7)) for a helical scan recorder comprises a stationary first drum (22) and a shaft (24) having a shaft first end (26) centrally mounted to the first drum and a shaft second end (28). The drum assembly further comprises a rotatable second drum (32) which has at least one transducing element (34) mounted thereon. The shaft (24) extends axially through the second drum (32) and the shaft second end (28) protrudes axially above the second drum (32). The drum assembly also comprises a physical support member (40, 40(7)) connected to the first drum (22). The physical support member (40, 40(7)) is connected to the first drum (22) and also connected to stabilize the shaft second end (28) while allowing rotation of the second drum (32). The physical support member (40, 40(7)) is connected to the shaft second end (28) to reduce deflection of the shaft second end (28) when the drum assembly is exposed to external vibration or shock.

Abstract: A helical scan tape recorder (30) comprises a rotatable scanner (84) and a transport system for transporting magnetic tape proximate the rotatable scanner in a manner so that information is recorded during a revolution of the scanner. A controller performs a pause routine (120) for pausing during a recording operation on tape. The pause routine, when executed, performs the steps of: determining a tape pause position reference value indicative of a pre-pause last recording position on the tape; recording an erase signal on the tape after the pre-pause last recording position; rewinding the tape; transporting the tape in a forward direction and obtaining a current tape position value; determining when the current tape position value reaches a predetermined value relative to the tape pause position reference value; and at beginning of a next revolution of the scanner, commencing recording of one or more post-pause stripes on the tape.

Abstract: New helical recording scanner architectures and transducing methods provide a consistent track pitch for helical tracks despite positional errors in placement of transducing elements (or sets of transducing elements) from their nominal positioning. The new scanners (85) are rotatable scanners having a vertical direction parallel to an axis of rotation of the scanner. Both first and second transducing elements are mounted on the scanner, and a tape drive (30) which comprises the scanner also includes a transport system for transporting magnetic tape (31) proximate the rotatable scanner in a manner so that information is transduced in helical tracks by the transducing elements during revolutions of the scanner.

Abstract: A helical scan tape recorder (30) comprises a rotatable scanner (85) upon which is mounted a first set of plural transducing heads (W1, W3) and a second set of transducing heads (W2, W4). A transport system transports magnetic tape (31) proximate the rotatable scanner in a manner so that information is transduced by at least one of the transducing heads during a revolution of the scanner. The sets of transducing heads are so mounted on the scanner with respect to azimuthal orientation of the transducing heads that all tracks transduced by the transducing heads have a desired width regardless of an error in physical distance separating the sets of transducing heads. In one aspect, the first set of plural transducing heads comprises a first head (W1) and a third head (W3), and the second set of plural transducing heads comprises a second head (W2) and a fourth head (W4).

Abstract: A head unit for use in a helical scan magnetic tape drive comprises a substrate having a substrate surface (300) and multiple thin film magnetic elements (D1, D2) formed on the substrate. Each of the multiple thin film magnetic elements has an interactive component for transducing information with respect to magnetic tape. The interactive components of at least two elements are situated on different planes at respective different distances from the substrate surface. None of the multiple elements of the head unit are situated to traverse a same path on the magnetic tape. Moreover, all of the multiple elements of the head unit perform a same type of transducing operation.

Abstract: A data cartridge handling apparatus comprises a ring-shaped carousel (40) rotatably mounted within a housing (22). Cartridge-accommodating cells (52) are angularly arranged about the carousel between an inner periphery (48) and an outer periphery (50) of the carousel. A transducing drive (70) is mounted within the housing and outside the outer periphery. A motor (60) rotates the carousel to facilitate selective alignment of a selected cell (52S) with the drive (70) along a radial dimension (106) of the carousel. A picker (100, 200) is mounted within the housing at a point within the inner periphery of the carousel (40). The picker (100, 200) has a picker arm (104, 204). A distal end of the picker arm has a gripper (110, 210) which selectively engages and disengages a data cartridge (72).

Abstract: A helical scan tape drive (20) has a cartridge compartment (24) for accommodating a single reel cartridge (26) of magnetic tape (56), and a take-up reel (50) which, with respect to a threading path (42), is not coplanar with the cartridge compartment. A threading system (40) grasps an end of the magnetic tape in the cartridge and transports the magnetic tape through the threading path. The threading path is configured such that the magnetic tape is at least partially wrapped around a rotatable scanner (30) before the end of the magnetic tape is attached to the take-up reel. The rotatable scanner has one or more elements (180, 182) for transducing information relative to the magnetic tape. The take-up reel is situated at a location either above or below the cartridge compartment for reducing footprint of the drive. In one embodiment, the take-up reel and the compartment are in an at least partially overlapping relationship.

Abstract: A scanner (3-85, 8-85, 9-85) for use in a helical scan magnetic transducing apparatus has a periphery upon which plural read tranducing elements (3-82) and plural write transducing elements (3-80) are mounted non-symmetrically. The plural write transducing elements are physically situated on the periphery of the scanner in M number of local groups (3-81), wherein the plural read transducing elements are physically situated on the periphery of the scanner in N number of local moveable groups (3-831, 3-832), and wherein M<N. Each of the moveable groups has a separate actuator (89) for adjusting position of the group.

Abstract: According to the invention, techniques for cleaning a rotary magneto-resistive head. Embodiments according to the invention are especially useful in tape drive systems, and the like. Embodiments can provide methods and apparatus for cleaning contaminant from rotary magneto-resistive heads while guarding against damage to the head from excess cleaning, and the like. Specific embodiments can control the rotational speed of a rotary magneto-resistive head in order to facilitate cleaning operations. Embodiments include a cleaning device and a control method, and are suited for use in a magneto-resistive head mounted on a rotary cylinder of a computer tape storage unit, for example, although application of the present invention is not limited to such embodiments.

Abstract: In a helical scan recording system, magnetic tape (31) is transported by a tape transport (98) proximate a rotating scanner (85). The scanner has a pair of read heads (82) mounted thereon, e.g., a first read head and a second read head, which travel in a helical direction on the magnetic tape in view of the transport of the tape and rotation of the scanner. A synchronization detection system (38) determines a first synchronization mark detection time at which a first synchronization mark is read by the first read head from the first track, and a second synchronization mark detection time at which a synchronization mark read by the second read head from the second track. A position error signal generator (100) develops a position error signal (PES) based upon a difference between the first synchronization mark detection time and the second synchronization mark detection time.

Abstract: A transducing head (740) for a magnetic tape recorder comprises a first magnetic pole (744) and a second magnetic pole (742) positioned to form a gap therebetween. The first magnetic pole (744) has a first magnetic pole width H3 along the gap and the second magnetic pole (744) has a second magnetic pole width H1 along the gap. The first magnetic pole width H3 and the second magnetic pole width H1 are formed to satisfy the relation H1<H3<3T<H2, wherein H2 is a physical tape contact width of the transducing head and 3T is a width of three adjacent recorded tracks traversed by the head.

Abstract: A cleaning wheel positioning mechanism for precisely controlling the contact pressure of a cleaning wheel against a recording drum in a magnetic recording system is presented. In accordance with the invention, the cleaning wheel positioning controller uses knowledge of the drum drive motor voltage (or current) to detect the contact pressure of the cleaning wheel against the drum. During a cleaning operation, which preferably occurs automatically during a periodic cycle, the cleaning wheel positioning controller first detects a reference drum motor voltage/current based on the drum drive motor voltage/current when the cleaning wheel is in its fully retracted position. Cleaning wheel positioning controller then monitors the drum drive motor voltage/current, and compares it to the reference drive motor voltage/current.

Abstract: A calibration cartridge (20) for an automated media library (60) comprises a cartridge case (30) having a calibration surface (35) and an electromagnetic transmissive channel (40). The electromagnetic transmissive channel transmits electromagnetic radiation incident upon the calibration surface at a radiation reception port (42) in a first position of the calibration cartridge so that the electromagnetic radiation travels interiorily through the calibration case and exits from the calibration cartridge at a radiation exit aperture (44) in a second position on the calibration surface. The calibration cartridge is usable in an automated information storage library which comprises plural cartridge-accommodating cells (64) and a drive (68).

Abstract: A method and system for monitoring and/or adjusting the positioning of a magnetic tape using central control packets that are recorded to the tape is presented. Central control packets are used for adjusting the timing of the read head signal over the tape, adapting the reel count to that of the drive at the time the tape was recorded, and monitoring filemarks for logical tape positioning.

Abstract: Cartridges (64) are loaded into or retrieved from an automated media library (20) either singly through an entry/exit port module (54), or by opening a library door (30) and inserting/removing a cartridge magazine (52) from a magazine cavity (50) of the library. Structures are provided for precluding against overinsertion of a cartridge. An entry/exit port cartridge overinsertion protection assembly (450) is provided to prevent overinsertion of a media cartridge loaded into the entry/exit port module. The entry/exit port cartridge overinsertion protection assembly includes a cartridge restraint member (452) which is pivoted away from a cartridge restraint position by a cartridge transport device (92) when the transport device seeks to obtain or deposit a cartridge at the entry/exit port. A cartridge restraint assembly (300) is also provided to guard against overinsertion of a cartridge stored in a cartridge magazine.

Abstract: An automated cartridge library has an essentially rectangular library frame which includes a frame front wall (22) and a frame back wall (24), and a library door (30) provided on the frame front wall. A transport actuator and guide region (90) is provided within the frame, the transport actuator and guide region including both a guideway along which a cartridge transport assembly (92) reciprocates and an actuator (124) which causes the cartridge transport assembly to rotate from a first transport position to a second transport position. A library front section includes a cartridge magazine cavity (50) and a entry/exit port module (54). A library rear section includes a region for tape drives (60) and an auxiliary cartridge magazine (70). Cartridge magazines (64) are insertable into the cartridge magazine cavity when the library door is opened so that a reference surface of the cartridges face the transport actuator and guide region.

Abstract: A robotic cartridge picker (92) for a cartridge library (20) has picker fingers (84) for selecting engaging and disengaging a media cartridge (64), and an electronic device (180) carried thereon. A ribbon cable (182) supplies at least one of power and an electrical signal to the electronic device. The robotic picker is rotatably mounted on a mounting block (140). The mounting block has a chamber (188) wherein a portion of the ribbon cable is carried in a variable coiled configuration to accommodate rotation of the robot about an axis (100). The variable coiled configuration facilitates the ribbon cable having a first degree of coiling when the picker robot rotates to a first position and a second degree of coiling when the picker robot rotates to a second position.

Abstract: A method and apparatus for varying track recording speed to maximize host-to-tape data transfer rates is presented. Variable data transfer rates of host systems and networks are accommodated by continually adjusting the tape speed to match the tape drive to the host's actual transfer rate. The speed of the tape is adjusted according to both the level of data present in the tape drive data buffer and whether the current mode of the drive is write mode or read mode. In the preferred embodiment, when the tape speed is accelerated or decelerated while writing a number of data track pairs to tape, a predetermined number of dummy track pairs are first written to tape at the current speed. On the next write head phase after the speed is increased or decreased as appropriate while the read heads are over the track, a predetermined number of dummy track pairs followed by more data track pairs are written to the tape at the new speed.

Abstract: A transformer-coupled tape drive (30) allows operation using a direct current (DC) content code. Usage of the DC content code is facilitated by a compensation circuit (240) which corrects timing distortion caused by the DC content code. The compensation circuit comprises both an emulation circuit (306) and a delay circuit (302). The emulation circuit (306) emulates a high pass filter action of a transformer (220) to provide an emulated high pass filter response signal (WD_HP). The delay circuit (302) modifies the modify timing of the write data signal in accordance with the emulated high pass filter response signal to output a compensated write data signal to the transformer (220).

Abstract: A method for detecting the location of falsely detected “good” data, or “rogue”, packets in a data buffer is presented. A segment-level CRC is generated over, and associated with, a buffer segment, and recorded along with the segment data onto a storage medium. During data recovery, only packets that pass a packet-level error detection test are allowed in the data buffer. Once a data segment is complete, a segment-level CRC test is performed over the recovered segment-level CRC and the entire recovered segment data. The segment contains a rogue packet if the segment-level CRC test fails. Reed-Solomon syndromes are generated and used to locate and optionally correct the rogue packets.