JPH01106382A - Rotary head type magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To improve surface recording density by dividing recording data into an editing unit, recording the data of one editing unit by dividing them into two or more data tracks, providing one or more tracks for an editing space between track groups of each editing unit, and giving the track for the editing space a role to guard a band. CONSTITUTION:The data in one vertical scanning period of a VTR are made into one editing unit, divided, for example, into 48 tracks, and recorded, and by making each one track placed before and after the data into the track for the editing space, totally 50 tracks are made into one editing block. Namely, a recording pattern with a rotary head is composed of data tracks 1A-24B and tracks 25A and 25B for the editing space, and since the editing is executed at every editing block unit, only the track widths of the tracks for the editing space are influenced by compatibility accuracy of track linearity at the time of the editing, and the width of the data track becomes always constant. Further, at the time of a reproducing, since the reproducing is executed with a head having the double width of the track width, the compatibility of the track linearity may be a + or -1/2 track or less.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to a rotary head type magnetic recording/reproducing device that involves editing.

Conventional technology The recording density of rotary head type magnetic recording and reproducing devices has been improved at both linear density and 1 degree of opening. In the case of (2), the track pitch is about 45 μm.

This is largely due to constraints due to mechanical precision.
This is because the track linearity may deviate by about 5 nm during compatibility.In order to prevent the playback quality from deteriorating at the editing point due to this difference in track linearity,
Conventionally, guard bands are provided between tracks.

Problems to be Solved by the Invention In the recording of high-definition television signals, digital VTRs, and the like, the amount of information to be recorded increases, and it is necessary to perform higher-density recording. However, in the conventional case where a guard band is provided to prevent deterioration of reproduced image quality at an editing point, there is a problem in that as the track width is reduced, the rate of loss in areal recording density due to the guard band increases. Therefore, the present invention attempts to prevent image quality deterioration at editing points without providing guard bands between tracks.

Means for Solving the Problems The present invention divides recorded data into editing units, records the data of one editing unit by dividing it into at least two data tracks, and records at least one data track between each editing unit. 1
This is a rotary head type magnetic recording/reproducing device provided with more tracks for editing space.

According to the present invention, an editing space track is arranged for each track group of each editing unit. Therefore, the difference in track linearity before and after the editing point only results in distortion of the track shape for this editing space, and does not affect the data track width. During editing, the editing space track plays the role of a guard band that was conventionally placed between tracks.

EXAMPLE Hereinafter, a first example of the present invention will be described with reference to FIG. 1 showing the recording pattern by the rotary head and FIG. 2 showing the head arrangement. This embodiment uses a VTR that records Basebird's high-definition television signal as digital data at approximately 1200 Mbps.
data (referred to as v) is divided into 48 tracks as one editing unit and recorded, and one track before and after each track is used as an editing space track to record a continuous wave of the shortest recording wavelength of the data, making a total of 60 tracks. There is one editing block. Furthermore, each track is alternately recorded by two types of heads with head widths twice the track width and different azimuth angles, and when recording in edit mode, the tape feed phase is set to track (y6). Editing is performed in units of editing blocks by allowing the playback to progress by a considerable amount compared to normal playback. Further, the head arrangement is as shown in FIG. 2, with two heads arranged every 90 degrees, and the effective tape winding angle is 270 degrees. Also, the azimuth of the head is head 3.
5, 7, 9 are A azimuth, heads 4, 6, 8°10
is B azimuth. The recording patterns by the rotary head of this embodiment as described above are as shown in FIG.
B is the data track 26A.

25B is a track for editing space. In this embodiment, as mentioned above, since editing is performed in units of editing blocks, only the track for the editing space is affected by the compatibility accuracy of track linearity during one editing, and the width of the data track is always constant. becomes. Furthermore, since reproduction is performed using a head twice the track width, the compatibility accuracy of the track linearity only needs to be equal to or less than 34) racks. In other words, editing is possible even if the track width is narrowed to twice the compatibility accuracy of the track linearity. In addition, in this embodiment, when recording in edit mode, the tape feed phase is set to (3A) compared to during normal playback.
I was able to advance by the equivalent of a truck.

During recording, half of the recorded track is erased by the next track because it is recorded using a wide head.

The tracks that remain as recording patterns are located from the center of the head (
%) This is because the center of the head coincides with the center of the track during playback.

A second embodiment of the present invention will be described below with reference to FIG. 2 showing the recording pattern by the rotary head and FIG. 2 showing the head arrangement. This embodiment is a VTR that records NTSG composite signals as digital data at approximately 12 oMbps), and the editing space track, which was two tracks in the first embodiment, is now one track, and the data track is This is a rotary head type magnetic recording/reproducing device in which at least the first track is erased by a rotary erasing head in a width greater than the track width before recording. In this embodiment, one frame of data is divided into 16 tracks, and six tracks are used as one editing block.

The head arrangement is as shown in Figure 4 (Head 3 of A azimuth and B
An azimuth head 4 is mounted as a recording head on the cylinder 2 facing each other at the same head height. This 2
The width of the head is set to 1.5 times the track pitch. On the other hand, the erase head 3.

The head width is 2.6 times the track pitch, and the height of the head is set at a height that allows the head 3 to scan the center of the A azimuth track in advance of the rack.

Further, 12 is a dummy head. With this head arrangement, a pattern as shown in FIG. 3 is recorded. When recording an edit,
If one editing block in FIG. 3 is to be inserted and recorded, the tape feed phase is first advanced by (%) tracks. This is for the same reason as the first embodiment. Next 1A
The rotary erasing head 11 erases the tracks 3'a, 8B, and 1B.

Next, the rotary erasing head 11 writes the tracks of fi2A and 1.
When (A) of track B and ('y()) of track 2B are erased, half of tracks 1A and 1B begin to be recorded by the recording/playback head 3.Next, recording/playback starts. Half of the 1B track and half of the 2A track are recorded by the head 3. In this way, while the rotary erasing head 11 is performing advance erasing, the recording/reproducing heads 3 and 4 are recording alternately. At the out point, tracks up to (A) of track 8B are erased, and the recording by the recording/reproducing head 3 is 8B.
It will be half of the A track and the 8B track. Therefore, according to this embodiment, the accuracy of track linearity is ±(A).
If the following conditions are met, deterioration due to compatibility accuracy of track linearity during editing will not occur.

As described above, according to this embodiment, the present invention can be realized even if the number of editing space tracks is one track, which is advantageous in improving areal recording density. In this example, the recording/reproducing head was a dual-purpose type, but by making the recording head the same width as the track width and making the playback head and erase head twice the track width, the compatibility accuracy of track linearity was improved. (It is also possible to allow even y-tracks.

Effects of the Invention According to the present invention, as mentioned above, during editing, the editing space track plays the role of the guard band that was conventionally provided between the tracks, thereby achieving narrow track pitch, high rotational speed rotary head type magnetic recording and reproducing. This has the great effect of improving the lateral recording density in the device.

[Brief explanation of the drawing]

FIG. 1 is a recording pattern diagram by the rotary head of the first embodiment, FIG. 2 is a head arrangement diagram of the same embodiment, FIG. 3 is a recording pattern diagram by the rotary head of the second embodiment, and FIG. 4 is a diagram of the recording pattern by the rotary head of the second embodiment. FIG. 3 is a head layout diagram of the same embodiment. 1... Tape, 2... Rotating cylinder,
3 to 10...recording/reproducing head, 11...rotating erasing head, 12...dummy head. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2

Claims (3)

[Claims] (1) Divide the recorded data into editing units, divide the data of one editing unit into at least two or more data tracks, and record at least one editing space track between the track groups of each editing unit. A rotary head type magnetic recording/reproducing device characterized in that: (2) A patent claim characterized in that the editing space track is one track, and at least the first track is erased by a rotating erasing head to a width greater than the track width before recording a data track during editing or splicing. A rotary head magnetic recording/reproducing device according to item 1. (3) The rotary head type magnetic recording/reproducing apparatus according to claim 1, wherein an erasing signal such as a continuous wave is recorded in the editing space track.