VCR head cleaning system that automatically detects head clogging upon playback
AssigneeSony Corporation
InventorsHideaki Miyahara, Jun Watanabe
Life of this patent
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Abstract
An ATF error signal is formed from a reproduction RF signal and supplied to an ATF discriminating unit 4 through an A/D converter by an ATF error arithmetic operation unit 1. The presence or absence of an ATF component is discriminated and supplied to a clog discrimination processing unit 5 by the ATF discriminating unit 4. The ATF discrimination processing unit 5 determines that a head clog has occurred in the case where the ATF component exists and the RF signal which is supplied from an RF discriminating unit 9 doesn't exist. A head cleaning is executed by controlling a loading motor 16 by a motor driver 14 on the basis of a cleaning process control 11 and making a head cleaning mechanism 17 operative.
Claims8
A magnetic recording and reproducing apparatus in which a signal is recorded and reproduced to/from a recording medium by a magnetic head mounted on a rotary head drum, wherein said signal is comprised of an information signal and a tracking control pilot signal recorded on said recording medium, and the rotation of the head drum produces a phase generatingpulse and a field generating pulse, the apparatus comprising:
- timing generating means for generating a timing signal based on said phase generating pulse and said field generating pulse;
- means for separating a low frequency component and a high frequency component of said signal reproduced by said magnetic head at a timing controlled by said timing signal generated by said timing generating means, wherein said high frequency component is said recorded information signal and said low frequency component is said tracking control pilot signal;
- head clog discriminating means for comparing a level of said low frequency component and a level of said high frequency component of said reproduced signal and, in the case where said low frequency component exists and said high frequency component does not exist, for discriminating that such a state is a head clog;
- and
- head cleaning means for cleaning said recording and reproducing head controlled by said head clog discriminating means.
A magnetic recording and reproducing apparatus in which a signal is recorded and reproduced to/from a recording medium by a magnetic head mounted on a rotary head drum, wherein said signal is comprised of an information signal and a tracking control pilot signal recorded on said recording medium, and the rotation of the head drum produces a phase generating pulse and a field generating pulse, the apparatus comprising:
- timing generating means for generating a timing signal based on said phase generating pulse and said field generating pulse;
- means for separating a low frequency component and a high frequency component of said signal reproduced by said magnetic head at a timing controlled by said timing signal generated by said timing generating means, wherein said high frequency component is said recorded information signal and said low frequency component is said tracking control pilot signal;
- head clog discriminating means for comparing a level of said low frequency component and a level of said high frequency component of said reproduced signal and, in the case where said low frequency component exists and said high frequency component does not exist, for discriminating that such a state is a head clog;
- head cleaning means for cleaning said recording and reproducing head controlled by said head clog discriminating means;
- and
- state display means for displaying a state of a recording and reproducing head controlled by said head clog discriminating means.
A helical-scan type magnetic tape recording and reproducing-apparatus including a magnetic head mounted on a rotary head drum for recording and generating from a tape a reproduction RF signal, and a low frequency tracking control pilot signal, wherein rotation of said rotary head drum produces a phase generating pulse and a field generating pulse, the apparatus comprising:
- interruption timing forming means for controlling a system timing based on said phase generating pulse and said field generating pulse;
- ATF discrimination processing means for discriminating whether said low frequency tracking control pilot signal is present on said tape at said system timing controlled by said interruption timing forming means;
- RF discrimination processing means for discriminating whether said high frequency RF signal is present on said tape at a timing controlled by said interruption timing forming means;
- head clog discriminating means for discriminating a head clog when said low frequency tracking control signal is found to be present by said ATF discrimination means and said high frequency RF signal is found to be absent by said RF discrimination processing means;
- and
- head cleaning means controlled by said head clog discriminating means for cleaning said drum.
Dependencies are inferred from the claim text.