Abstract: A helical scan transport apparatus for reading and writing data on to a magnetic recording tape which is wound on a supply reel rotatably mounted within a removable tape cartridge includes a chassis having a front end portion and rear end portion. An elevator assembly is mounted on the chassis at the front end. The elevator assembly is configured to receive the tape cartridge and to position the tape cartridge in a loaded position. A take-up reel assembly is coupled to the chassis at the rear end position. A helical deck is mounted on a central portion of the chassis between the elevator assembly and the take-up reel assembly. The helical deck includes a rotary read/write head, a substantially linear tape loading path between the elevator assembly and the take-up reel assembly, and a movable guide for the seizing the tape from the tape loading path and for at least partially wrapping the tape around the rotary head.

Abstract: A helical scan transport apparatus for reading and writing data on to a magnetic recording tape which is wound on a supply reel rotatably mounted within a removable tape cartridge is disclosed. The helical transport includes a chassis having a front end portion and a rear end portion. An elevator assembly is mounted on the chassis at the front end. The elevator assembly is configured to receive the tape cartridge and to position the tape cartridge in a loaded position. A take-up reel assembly is coupled to the chassis at the rear end portion. A helical deck is mounted on a central portion of the chassis between the elevator assembly and the take-up reel assembly. The helical deck includes a rotary read/write head, a substantially linear tape loading path between the elevator assembly and the take-up reel assembly, and a movable guide for seizing the tape from the tape loading path and for at least partially wrapping the tape around the rotary head.

Abstract: An apparatus for reducing head wear in a helical scan tape transport passes a flow of relatively clean, dry air through a transport housing without allowing the flow of air to flow directly across the rotary head assembly. Air from a fan positioned at a rear portion of the transport cools a power supply and creates a positive air pressure within the transport housing. The air is heated by the power supply before it passes through the transport housing, so that only relatively "dry" air reaches the rotary head assembly. The air is exhausted out the opening through which a tape is loaded. This arrangement substantially reduces the possibility of contaminants entering the transport housing. Additionally, the air cleans a magnetic recording tape on a tape cartridge as the tape is passes through the transport housing so that only relatively "clean" tape reaches the rotary head assembly.

Abstract: The control software and hardware in the tape drive control unit creates and manages a header segment at the beginning of the magnetic tape. This header is interposed between a leader portion of the magnetic tape on the 3480-type cartridge and the remainder of the magnetic tape contained therein. This header segment contains two sections, a first of which is a data record directory that is used by the control unit to denote the location of each data record written on to the magnetic tape as well as administrative information associated with the data record. The second section of the header is an administrative information section that contains data relating to the magnetic tape itself.

Abstract: A novel method is disclosed for performing a high speed search for a selected data block or data file utilizing any one of several presently existing helical scan tape formats which utilize, in addition to the helically scanned tracks, one or more longitudinal tracks for recording indexing information indicative of the location of data blocks and file marks stored on the associated helical tracks. Data file location information is written to a header area on a series of helical tracks and to one (or more) of the longitudinal tracks when a data block or a file mark is written to a tape. A high speed search for a desired data block or data file can then be performed using this track location information.

Abstract: The video-to-data converter buffers and converts the video data received from a camera or a conventional video tape drive into a data record format that is compatible with a computer data tape drive subsystem and its media, such as a 3480-type magnetic tape cartridge. In addition, a header is interposed between a leader portion of the magnetic tape and the remainder of the magnetic tape. This header segment contains two sections, a first of which is a data record directory that is used by the control unit to denote the location of each data record on the magnetic tape as well as administrative data associated with the data record. The second section of the header is an administrative information section that contains data relating to the magnetic tape itself.

Abstract: In response to the mounting of a magnetic tape on the tape drive, the tape drive begins reading data from the tape into the preload buffer while concurrently signalling the data processor that the tape drive is instantaneously available to read/write data. The data processor can then begin the data transfer operation without incurring the delay occasion by media set up time. The data that is transferred from magnetic tape is stored in the preload buffer in anticipation of the data processor issuing a data read command. Upon receipt of the data read command, the tape drive reads the data out of the preload buffer to the data processor via the data channel while simultaneously reading data from the magnetic tape into the preload buffer.

Abstract: The cleaning tape comprises a substrate on which is overlaid a coating that provides a mechanical abrading surface to clean the elements in the tape path, such as the read/write heads. The coating has a high coefficient of friction to remove and retain the residues that have accumulated on the read/write heads. The coating is impregnated with or encloses a cleaning solvent that is controllably released by the mechanical movement of the cleaning tape over the read/write heads. The cleaning solvent can be isopropyl alcohol or other solvents that are encapsulated in some manner in the cleaning tape. As the solvent is released on to the read/write heads, it chemically loosens the debris which the abrasive coating can then mechanically remove from the read/write heads and also retain on the abrasive coating.

Abstract: Control software and hardware in the tape drive control unit creates and manages a header segment at the beginning of the magnetic tape. This header segment includes an administrative information section that contains data relating to the magnetic tape itself. The administrative information includes read/write status information such as the write protect status of the magnetic tape that enables the tape drive control unit to manage the data records written onto the magnetic tape without reference to any other source of administrative data. In addition, each data record written on the magnetic tape includes a header which denotes the read/write status of the data record.

Abstract: The control software and hardware in the tape drive control unit creates and manages a multiple level error detection and correction system to protect the data written on the magnetic tape. The helical scan data write circuits operate on the received stream of data records to produce two orthogonal error detection and correction codes on a scan group level. The data write circuit divides the received stream of data records into data segments, each of which contains a predetermined number of data bytes. A first of these scan group error codes is generated on a per data segment basis while a second scan group error is generated across multiple data segments. A third level error correction code is also used to protect an entire scan group rather than data on a per byte basis. The third level error correction code generator produces an error code over a predetermined number of sequentially written scan groups to enable the control unit to reconstruct an entire scan group if its data integrity is compromised.

Abstract: This magnetic tape cartridge has the same exterior dimensions as a conventional 3480-type magnetic tape cartridge but houses different media. To clearly identify the media contained in the cartridge, a label receiving recess in included on the back of the cartridge. A human readable and machine readable label can be inserted into this recess to identify the media contained in this cartridge. Additional label recesses are provided juxtaposed to the media identification recess and on the top and side of the cartridge to receive user installed labels to uniquely identify the cartridge.

Abstract: The control software and hardware in the tape drive control unit creates and manages a header segment at the beginning of the magnetic tape. This header is interposed between a leader portion of the magnetic tape on the 3480-type cartridge and the remainder of the magnetic tape contained therein. This header segment contains two sections, a first of which is a data record directory that is used by the control unit to denote the location of each data record written on to the magnetic tape as well as administrative information associated with the data record. The second section of the header is an administrative information section that contains data relating to the magnetic tape itself. The stream of data records is divided into data segments, a plurality of which comprise a single helical scan track. The helical scan tracks are formed into scan groups and written on the magnetic tape.

Abstract: A universal data storage element presents a data storage element of uniform form factor while enables the selection of media types to provide variable data recording characteristics. Using multiple types of media in an automated library system or a manually operated media storage retrieval system is now possible with a uniform form factor exists in all of the data storage elements. Physical characteristics of the media are identified by a plurality of coding apertures outside the data storage element. A drive element decodes and identifies the type of media from the apertures.

Abstract: This system makes use of a tape cassette helical scan tape transport and a modified 3480-type magnetic tape cartridge as the data storage media. The merging of these two incompatible elements is accomplished by the use of a novel interface that implements a "virtual tape cassette" by providing a takeup reel positioned with the magnetic tape cartridge in a relationship that substantially matches the format of a magnetic tape cassette. A short tape threading arm is used to retrieve the leader block from the tape cartridge and thread the magnetic tape over a short tape threading path to the takeup reel. Once the tape is affixed to the takeup reel, the helical scan tape loading mechanism transports the length of tape that is now exposed between the tape cartridge and the takeup reel to the rotary heads. The helical scan magnetic tape cartridge has the same exterior dimensions as a conventional 3480-type magnetic tape cartridge but is implemented in the inverse configuration.

Abstract: A peripheral system has one or more buffered control units connected to a plurality of peripheral devices. Operation times of the devices are marked by the buffer and controls which overlap device operations, queue device operations in a priority set of queues, and prioritize peripheral system operations. Plural specialized interconnections between each control unit and the devices include a preparatory connection for transfer of preparatory commands to devices, a tag or control connection for device selection, deselection and control and a data-command connection for signal transfers between a selecting control unit and a selected peripheral device.

Abstract: In a machine having a reciprocating original document handling carriage such as a copier, a selectively operable roller is positioned for removing documents from the upper surface of the carriage. The roller is driven by movement of the carriage by power stored from carriage movement or by an independent power source. Continuously driven rollers are positionable in coordination with the end of a run of copies for a given document to eject the document onto an output tray as the carriage returns.

Abstract: In a machine having a reciprocating original document handling carriage such as a copier, a roller at the bottom of a sloped ramp rests on the upper surface of the carriage. Documents placed on the ramp slide downward until the leading edge is at the nip between the roller and carriage surface. Movement of the carriage pulls the document from the tray onto the carriage surface for scanning. An additional roller can be included to provide automatic document ejection by pushing the document onto an output tray as the carriage returns.

Abstract: Programmed controllers execute sequences of control functions for controlling a device. External noise can cause controller malfunctions on critically operated devices. Proper sequencing is verified by assigning access key/check codes to particular sequences. A check key code is generated during execution of a sequence only if the sequence is properly executed by the programmed controller. At completion of the control sequence, the generated code is compared with the access or original code for verifying appropriate programmed controller sequencing. Several sequences can be embedded or nested in each other, each having its own check key with the overall sequence also having an independent check key.