Apparatus for longitudinal bidirectional recording with equal length tracks

A parallel scanning video tape recording and/or reproducing apparatus which performs recording and reproducing in both forward and reverse driving of a video tape, comprising:

• a rotary head drum carrying an azimuth-pair-head constituted of first and second magnetic heads, said first magnetic head being formed with a first azimuth gap and said second magnetic head being formed with a second azimuth gap with an azimuth angle different from that of said first azimuth gap, said first and second magnetic heads being cooperative in forming a single longitudinally extending track on a video tape in one cycle of rotation of said rotary head drum, said track having a first section formed by means of said first magnetic head and having a first azimuth pattern and a second section formed by means of said second magnetic head and having a second azimuth pattern which is different from said first azimuth pattern of said first section;
• means for guiding said video tape onto said rotary head drum for recording and reproduction of video signal, said guiding means wrapping said video tape on the periphery of said rotary head drum so that the longitudinal axis of said magnetic tape lies in perpendicular to the rotation axis of said rotary head drum and that said video tape mates with the periphery of said rotary head drum in a predetermined angular range;
• means, cooperative with said azimuth-pair-head, for shifting the latter in a direction parallel to said rotation axis of said rotary head drum, said shifting means shifting said azimuth-pair-head in axial first direction for forming first longitudinal tracks which are separated from each other with a predetermined width of clearance left therebetween, and in an axial second direction opposite to said first direction for forming second longitudinal tracks in said clearances between adjacent first tracks, and
• means for adjusting a scanning angular range over which said azimuth-pair-head scans the video tape to form longitudinal tracks of equal longitudinal length both in forward recording and reverse recording.

A method for recording and/or reproducing formation on a plurality of tracks formed on magnetic tape and extending in parallel to the longitudinal axis of said magnetic tape, comprising the steps of:

• providing a rotary head drum with a first and a second magnetic head constituting an azimuth-pair-head, said first and second magnetic heads being formed with azimuth gaps with mutually different azimuth angles and cooperating with each other for scanning a single track during one cycle of rotation of said rotary head drum;
• guiding said magnetic tape on said rotary head drum in such a manner that said magnetic tape runs in parallel to the motion path of said azimuth-pair-head and is wrapped onto the periphery of said rotary head drum in a predetermined angular range;
• shifting said azimuth-pair-head from one track to other track every one cycle of rotation of said rotary head drum, wherein a shifting magnitude of said azimuth-pair-head in every shifting operation substantially corresponds to twice the axial width of individual track for scanning every other track;
• driving said tape recording medium along a tape path in both forward and reverse directions;
• and
• adjusting a scanning angular range over which said heads scan said tape in response to the driving direction of said tape whereby the longitudinal length of each of said tracks formed by said heads per rotation of said rotary head drum is equal in both forward recording and reverse recording.

A parallel scanning tape recording and/or reproducing apparatus for a tape recording medium, comprising:

• a rotary head drum for rotating in a fixed direction,
• head means carried by said rotary head drum for recording and/or reproducing a signal on and/or from said tape recording medium,
• means for guiding said tape recording medium onto said rotary head drum, said guiding means wrapping said tape recording medium on the periphery of said rotary head drum so that the longitudinal axis of said tape recording medium lies perpendicular to the rotation axis of said rotary head drum and so that said tape recording medium mates with the periphery of said rotary head drum in a predetermined angular range;
• shifting means for shifting said head means in a direction parallel to said rotation axis of said rotary head drum so that the position of tracks formed by said head means is changed in the direction of the width of said tape recording medium;
• driving means for driving said tape recording medium along a tape path in both forward and reverse directions;
• and
• adjusting means for adjusting a scanning angular range over which said head means scans said tape recording medium in response to the driving direction of said tape recording medium whereby the longitudinal length of each of said tracks formed by said head means per rotation of said rotary head drum is equal in both forward recording and reverse recording.