Abstract: An encoder system comprising an encoder assembly and an encoder alignment structure is disclosed. The encoder assembly may include at least a coding member, a hub, and a housing. The encoder alignment structure may comprise a major surface, a plurality of catches, and a recessed region. The major surface may be coupled with the housing to substantially enclose the hub and the coding member. The plurality of catches may be disposed around the periphery of the major surface and may be configured to secure the encoder alignment structure to the housing. The recessed region of the major surface may be converging from the periphery of the major surface between two of the plurality of catches towards the hub so as to provide access for a user to adjust the hub around the axis of rotation.
September 17, 2014
Date of Patent:
October 18, 2016
Avago Technologies General IP (Singapore) Pte. Ltd.
Siow Ming Tan, Kek Leong Yap, Chong Hon Lim, Andrew Tuck Loon Kuan
Abstract: A recording apparatus of a tape-shaped magnetic recording medium includes a transfer unit, a recording head, a signal-processing unit and a control unit. The transfer unit transfers a tape-shaped magnetic recording medium having an anisotropic property oblique with respect to the thickness direction in a forward or reversed direction. The recording head is positioned in such a way that a recording track is formed on the traveling tape-shaped magnetic recording medium, which is transferred by the transfer unit, in a direction parallel to the transfer direction of the tape-shaped magnetic recording medium. Connected to the recording head, the signal-processing unit receives a signal to be recorded onto the tape-shaped magnetic recording medium. The signal-processing unit then carries out signal processing required for an operation to write the signal to be recorded onto the tape-shaped magnetic recording medium.
Abstract: A drive and method of identifying write velocity during reading are provided. When a track is being read, the data signal is processed prior to determining the data stream to identify the velocity with which the track data were written. The read channel is adjusted based on the identified velocity to compensate for write channel transfer function variation.
Abstract: A control system compensates for web tension variation caused by a first spool, (A) determines rotational frequency of the first spool; (B) determines variation in rotational velocity at the second spool which occurs at the (A) first spool frequency; (C) determines the rotational position at the first spool corresponding to the (B) variation in rotational velocity at the second spool; (D) calculates a drive motor profile for the first spool which tends to cancel the (B) variation in rotational velocity at the second spool; and (E) superimposes the (D) drive motor profile on a first spool drive motor at the (C) determined rotational position of the first spool.
February 15, 2002
August 21, 2003
International Business Machines Corporation
Alex Chliwnyj, David Michael Davis, David Lee Swanson
Abstract: A servo control apparatus controls operation of a to-be-controlled object through execution of software based on control data and reference data. An operation-signal generating portion generates an operation signal having a frequency representing the operation of the to-be-controlled object. A clock-signal generating portion generates a clock signal having a frequency controlled in accordance with the control data. A counting portion measures a time corresponding to the period of the operation-pulse signal by counting pulses of the clock signal, and generates a count value. A controlling portion controls the operation of the to-be-controlled object through execution of software based on the count value and the reference data.
Abstract: A sealed audio cassette player for playing a single permanently installed audio tape. The player is primarily intended for use with cassettes containing a spoken book, such as the Bible. In one embodiment, frequency indicia are provided on the tape for indicating tape linear speed. A drive motor drives the cassette take up spindle at a predetermined tape linear speed of less than about 0.5 inch per second with rotation of the drive motor varied in accordance with the indicia to maintain a constant tape linear speed. In an alternate embodiment a drive motor drives the cassette take up reel at a constant speed, so that the speed of movement of the tape past an audio pickup head constantly varies. The cassette is recorded with an identical constant speed take up, so that only cassettes so made will work in the player. The cassette is recorded with an identical constant speed take up, so that only cassettes so made will work in the player.
Abstract: An error component such as an eccentricity implicated in an encoder itself is superimposed upon a detected value from an FG due to an assembly error of assemblies themselves and in the manufacturing process. As a result, a speed could not be controlled with a high accuracy and wow and flatter could not be reduced. A tape speed (TSS) signal detected and corrected from the tape transport by FG and PG is inputted into a PLL loop within a data controller (TBC) of a reproducing system. A reproduced signal is converted by an A/D converter in response to a reference clock generated therein and this data is temporarily stored in an FIFO. When this data is reconverted by a D/A converter into an analog signal, if this data is sequentially converted at a timing of an absolute control clock of a quartz oscillator, then it is possible to eliminate the error component superimposed upon the head reproduced signal.
Abstract: Commutators on a direct current motor run at low speed for an extended period of time get covered with a coating that makes the interface between the commutator and the brushes unreliable especially with the low speed, low current operation. This is especially true for drive motors in a data processing tape drive unit where speed control is critical. The brush to commutator interface can be cleaned by applying a very high electrical current to the motor and varying the polarity of the current with a variable duty cycle to obtain the maximum cleaning currents in a relatively short time without dismantling the motors.
November 12, 1999
Date of Patent:
February 20, 2001
International Business Machines Corporation