JPH03187003A - rotating erase head - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is applicable to VTRs (video tape recorders) and digital
The present invention relates to a rotary erasing head included in a magnetic recording/reproducing device such as an AT (digital audio tape recorder).

[Conventional technology]

A VH3 standard VTR will be cited as an example of a magnetic recording/reproducing device, and its rotary erasing head will be explained.

The VH3 standard includes two types of recording modes with different tape running speeds: standard time recording mode (hereinafter referred to as SP).
mode) and long-time recording mode (hereinafter abbreviated as EP mode).

The recording track width differs depending on the recording mode, and as shown in FIG. 3, the width of the recording track 9 recorded in the SP mode is wide, and the recording track width is 58 μm, and the width of the recording track 9 recorded in the EP mode is wide. The width of the track 10 is narrow, and its recording track width is 19.3 μm. On the magnetic tape 8 (magnetic recording medium), this recording track 9 is
A large number of recording tracks (or recording tracks 10) are arranged diagonally, and a video signal for one field is recorded on each track. Then, two recording tracks 9 and 9 (or
An image of 1 frame is recorded on recording track 10 (10).

When erasing the video signal recorded on this recording track 9 (or recording track 10), in a consumer VTR 1 that employs a rotating erasing head, for example, in a table top type (stationary type) VTR, the rotating erasing head So-called frame erasing is performed, in which the width is set to about 116 μm, which is twice the recording track width in SP mode (58 μm), and one frame at a time is erased, or the track width is changed to S
So-called field erasing is performed in which each field is erased at a width of approximately 58 μm, which is approximately the same as the P mode recording track width.

The head arrangement for frame erasing is shown in FIG. 4(a).

On the rotating drum 4, a rotating erase head 3, a Hi-Fi audio head 5, and a video head 6 are arranged at 60 degree intervals, and facing these at 180 degrees are a dummy head 7 for rotational balance, a Hi-Fi audio head 5, and a video head 6. -Fi audio head 5,
A video head 6 is arranged. Note that the video head 6 is of a double azimuth type, and two chip cores for SP mode and EP mode are provided on one substrate. Further, the track width of the rotary erasing head 3 is approximately 116 μm, as described above.

Next, FIG. 4(b) shows the head arrangement when field erasing is performed.

This is an arrangement in which both the rotating erasing head 3 and the camera head 7 are replaced with the rotating erasing head 3a in the head arrangement for frame erasing (FIG. 4(a)). Note that the track width of the rotary erasing head 3a is approximately 58 μm, as described above.

[Problem to be solved by the invention]

However, in the conventional configuration described above, when erasing the recording on the recording track 10 recorded in the EP mode, unnecessary erasure may be performed. This is because, as shown in FIG. 5, the track width of the rotary erasing head 3 that performs frame erasing corresponds to 3 frames in EP mode, so frame erasing is performed in units of 3 frames in EP mode. . Similarly, since the track width of the rotary erasing head 3a that performs field erasing corresponds to three fields in the EP mode, field erasing is performed in units of three fields in the EP mode.

Therefore, in order to prevent such unnecessary erasing from being performed, as shown in FIG. Alternatively, it is conceivable to newly provide a rotating erasing head 3C on the rotating drum 4 for performing field erasing exclusively for the EP mode.

However, this increases the number of parts, and as is clear from Figures (a) and (b), the head arrangement becomes complicated due to the dimensional constraints of the rotating drum 4, and the number of manufacturing steps increases. There is a problem.

[Means to solve the problem]

In order to solve the above-mentioned problems, the rotating erasing head of the present invention erases information on a magnetic recording medium capable of recording data with a plurality of different recording track widths. It is characterized in that a plurality of magnetic heads each having a track width are provided on the same substrate.

[For production]

According to the above configuration, since a plurality of magnetic heads having a track width corresponding to each of a plurality of different recording track widths are provided, recording can be erased using a magnetic head having a track width corresponding to each recording track width. , only recordings on a predetermined recording track can be erased. Furthermore, since the plurality of magnetic heads are provided on the same substrate at this time, the arrangement of the heads on the rotating drum is not complicated.

〔Example〕

As one embodiment of the present invention, a rotary erasing head included in a VH3 standard VTR will be described below with reference to FIGS. 1 and 2. Note that members having the same functions as those shown in the drawings of the conventional example are given the same reference numerals.

The rotary erasing head 3 according to the present invention is shown in a schematic front view in FIG. 1(a), a schematic plan view in FIG. 1(b), and an enlarged view of part A in FIG. As shown, two magnetic heads 1a and 1b having different track widths are provided on the same substrate 2. In addition, the magnetic head 1a.
1b has a structure in which a coil is wound around chip cores lla and flb.

FIG. 2(a) shows the head arrangement when the rotary erasing head 3 is used to erase frames of video signals recorded on a magnetic recording medium.

On the rotating drum 4, a rotating erasing head 3, a Hi-Fi audio head 5, and a video head 6 are arranged at 60 degree intervals, and facing these at 180 degrees are a dummy head 7 for rotational balance, a Hi- Fi audio head 5,
A video head 6 is arranged. Note that the video head 6 is of a double azimuth type, and two chip cores for SP mode and EP mode are provided on one substrate.

In the rotary erase head 3, the track width of the magnetic head 1a is set to approximately 38.6 μm, which is approximately twice the recording track width (19.3 μm) in the EP mode.
The track width of b is the recording track width of SP mode (58
116 μm, which is approximately twice that of μm).

In the above configuration, in the SP mode, frame erasing is performed by the magnetic head 1b of the rotary erasing head 3, and E
In the P mode, frame erasing is performed by the magnetic head 1a of the rotary erasing head 3. At this time, since the track widths of the magnetic heads 1a and 1b are each set to approximately twice the recording track width in the SP mode or the BP mode, erasing can be performed frame by frame in either mode, and unnecessary erasing is unnecessary. is not performed.

Next, FIG. 2(b) shows the head arrangement when performing field erasing.

This is an arrangement in which both the rotating erasing head 3 and the dummy head 7 are replaced with the rotating erasing head 3 in the head arrangement (FIG. 2(a)) when performing frame erasing. The two rotary erasing heads 3, 3 are arranged on the rotary drum 4 so that the magnetic heads 1a, 1b face each other at 180 degrees.

In the rotary erasing head 3, the track width of the magnetic head la is set approximately equal to the recording track width in the EP mode, and the track width of the magnetic head 1b is set approximately equal to the recording track width in the SP mode.

In the above configuration, in the SP mode, field erasing is performed by the magnetic head lb of the rotary erasing head 3,
In the EP mode, field erasing is performed by the magnetic head 1a of the rotary erasing head 3. And at this time,
The track width of the magnetic heads 1a and 1b is SP
Since the recording track width is set approximately equal to the recording track width in mode or EP mode, erasure can be performed field by field in either mode, and unnecessary erasure is not performed as in frame erasure.

In addition, whether performing frame erasing or field erasing, the two magnetic heads 1a and 1b are mounted on the same substrate.
(Fig. 1(b)), the head arrangement on the rotating drum 4 is not complicated as shown in Fig. 6(a) and (b), and the conventional example (Fig. 4(a)) and (b)). Therefore, the number of manufacturing steps does not increase significantly.

In the above embodiments, the rotary erasing head included in a VH5 standard VTR has been described, but the present invention can also be applied to a DAT or the like. It is also applicable to cases where there are three or more different recording track widths.

〔Effect of the invention〕

As described above, the rotary erasing head of the present invention includes a plurality of magnetic heads each having a track width corresponding to each of a plurality of different recording track widths. Since the recording can be erased with , only the information on the predetermined recording track can be erased without unnecessary erasure of information on the recording track.

Furthermore, since the plurality of magnetic heads are provided on the same substrate, the arrangement of the heads on the rotating drum does not become complicated, and the number of manufacturing steps does not increase significantly.

[Brief explanation of drawings]

1 and 2 show an embodiment of the present invention. FIGS. 1(a) and 1(b) are a front view and a plan view, respectively, of a rotary erasing head according to the present invention. FIG. 1(C) is an enlarged view of section A in FIG. 1(a). FIGS. 2(a) and 2(b) are diagrams showing the arrangement of heads on a rotating drum when performing frame erasing and field erasing, respectively. 3 to 6 show conventional examples. FIG. 3 is a diagram illustrating recording track widths in the standard time recording mode and long-time recording mode of the VHS standard. FIGS. 4(a) and 4(b) are diagrams showing the arrangement of heads on a rotating drum when performing frame erasing and field erasing, respectively. FIG. 5 is a diagram illustrating an erasing range when information on a recording track recorded in a long-time recording mode is erased by a conventional rotary erasing head. Figures 6(a) and (b) show the potential on the rotating drum when a rotating erasing head for frame erasing and a rotating erasing head for field erasing, respectively, dedicated to long-time recording mode, are newly installed. It is a head arrangement diagram. la and 1b are magnetic heads, 2 is a substrate, 3 is a rotating erasing head, 4 is a rotating drum, 9 and 10 are recording tracks, lla
-llb is a chip core.

Claims (1)

[Claims] 1. In a rotary erasing head for erasing information on a magnetic recording medium capable of recording information with a plurality of different recording track widths, a plurality of magnetic heads each having a track width corresponding to each of the recording track widths are provided. A rotary erasing head characterized by being provided on the same substrate.