JPH03269820A - Rotary drum for magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To decrease magnetic crosstalks so as to attain higher image quality and to prevent the damage of a tape by contact by setting the gap in the nearest part of the head cores of two heads adjacent to each other within a prescribed range. CONSTITUTION:The gap between the head core 3 and head core 4 of the head 1 and head 2 which are adjacent to each other and are mounted to the drum 5 among plural pieces of the heads which are in proximity to each other and act simultaneously is provided to >=1.3 mm, by which the magnetic crosstalks between the head 1 and the head 2 are decreased to -50 dB and the sufficient image quality is obtd. The gap D between the head core 3 and the head core 4 is confined to <=2/3 the inter-gap distance A of the head 1 and the head 2, by which the contact of the front surface edge 6 of the head core 3 or the front surface edge 7 of the head core 4 with the tape 8 is obviated and the damaging of the tape 8 is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a rotating drum of a magnetic recording/reproducing device equipped with a plurality of heads.

[Prior Art] In recent years, in magnetic recording and reproducing devices (hereinafter referred to as VTRs), especially broadcast VTRs, in order to meet the demands for higher image quality and smaller size, multiple heads on a rotating drum are mounted
A method of separating signals and recording and reproducing them is becoming mainstream.

The conventional structure of a rotating drum of a YC separation type VTR, which is one of this type of VTR, is shown in FIGS. 4 and 5.

In FIGS. 4 and 5, head 1 and head 2 are attached to drum 5 in close proximity, head 1 records a Y signal (luminance signal), and head 2 records a C signal (chrominance signal). It's playing.

Here, the gap distance between heads 1 and 2 is A1, and the width of the herad core 3 on the side adjacent to head 2 of head 1 is B.
, the width of the head core 4 on the side adjacent to the head 1 of the head 2 is 01, and the gap between the radial core 3 and the radial core 4 is d, then the specific values generally show the following values. .

First, in the case shown in FIG. 4, A was 4.2 mm, B and C were 1.6 ohm, and D was 1.0 mm. That is, D was less than l, 3 mm.

Next, as shown in Fig. 5, A is 4.2 mm, B and C are 0.5 mm, and D is 3.2 mm.
It exceeded 2.8 mm, which is 2/3 of the gap distance A between heads 1 and 2.

[Problems to be solved by the invention] First, in the conventional rotating drum as shown in FIG.
Since the head core 3 of the head core 3 and the head core 4 of the head core 2 are too close to each other, and because the heads 1 and 2 perform recording or reproduction simultaneously, there is a magnetic field between the heads 1 and 2 during recording or reproduction. Lostalk was occurring at a high level. Therefore, there was a problem in that a beat occurred between the Y signal and the C signal, degrading the image quality.

Next, in the conventional rotating drum as shown in FIG. 5, the level of magnetic crosstalk is sufficiently small because the distance between the head core 3 and the head core 4 is large. There was a problem in that the tape 8 came into contact with the tape 8 and the tape 8 was damaged.

The present invention solves the above-mentioned problems by reducing the magnetic crosstalk that occurs between multiple heads that are close to each other and working simultaneously, thereby realizing high image quality, and also achieving reliability without damaging the tape. The purpose is to provide a rotating drum for a magnetic recording and reproducing device with high quality.

[Means for Solving the Problems] In order to achieve the above object, the rotating drum of the magnetic recording and reproducing device of the present invention has a magnetic head equipped with a plurality of heads that are close to each other and simultaneously record and reproduce signals of different types. A rotating drum of a recording/reproducing device, wherein the gap between two adjacent heads among the plurality of heads at the closest point is 1.
．． It is characterized in that there are three or more plates and the gap distance between the two adjacent heads is 2/3 or less.

[Function] According to the configuration of the present invention described above, since the gap between two adjacent heads is 1.3 mm or more, magnetic crosstalk is sufficiently small and high image quality can be achieved.

Furthermore, since the gap between the two heads is less than 2/3 of the distance between the two heads, the front edge of the head does not come into contact with the tape, and the tape is not damaged.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 shows an embodiment of the present invention.

In FIG. 1, head 1 and head 2 are mounted on drum 5 in close proximity. The gap distance A between the heads 1 and 2 is 4.2 mm.

The width B of the head core 3 is 1.3 mm.
The width C of is the same <1.3 mm. Therefore, the gap D between the head core 3 and the head core 4 is 1.6 mm, and 1.
3+mn or more.

Figure 2 shows the gap D between the head core 3 and the head core 4,
The relationship of magnetic crosstalk between head 1 and head 2 is shown. From the same figure, it can be confirmed that if the gap D between the head core 3 and the helad core 4 is 1.3- or more, the magnetic crosstalk between the heads 1 and 2 will be less than -50 bB, and sufficient image quality can be obtained. .

Also, FIG. 3 shows the gap distance A between heads 1 and 2, and the tape contact length E of the head core 3 in FIG.
and the tape contact length F of the head core 4.

In FIG. 3, as A becomes larger, the tape enters inside the drum between the two heads, and E and F become larger. E
And F is 1/6 of A. In order to prevent the front edge 6 or 7 from coming into contact with the tape, the width B of the head core 3 and the width C of the head core 4 must be equal to or greater than E and F, in other words, equal to or greater than 1/6 of A. In other words, the gap D between the head core 3 and the head core 4 is determined from the gap distance A between the heads 1 and 2 by 1/1 of A, which is the minimum necessary width B of the head core 3.
6 and 1/1 of A, which is the minimum necessary width C of the herad core 4.
It can be confirmed that the distance must be less than 6, in other words, 2/3 of A or less.

In the case of Fig. 1, D is 1.6 mm, which is smaller than 2.8 mm, which is 2/3 of A's 4°2 plate. 8 does not come into contact and does not damage the tape 8.

As described above, according to the rotating drum of this embodiment, the head 1
Since the gap D between head 1 and head 2 is 1.3 mm or more and less than 2/3 of the gap distance A between head 1 and head 2, the magnetic crosstalk between head 1 and head 2 is less than -50 bB. , is sufficiently small to achieve high image quality, and furthermore, the front edge 6 and the front edge 7 do not come into contact with the tape 8 and do not damage the tape 8.

Although this embodiment has been described using two heads that are close to each other, the present invention can be similarly applied to three or more heads that are close to each other. Furthermore, the present invention can be applied not only to the rotating drum of a YC separation type VTR, but also to other types.

[Effects of the Invention] As is clear from the above embodiments, according to the present invention, the gap between the closest parts of the head cores of two adjacent heads among a plurality of heads that approach and act simultaneously can be reduced. Since it is 1.3 mm or more and less than 2/3 of the gap distance between the two adjacent heads, magnetic crosstalk is sufficiently small and high image quality is achieved, and the front edge of the head does not come into contact with the tape, so the tape It is possible to achieve the excellent effect of providing a highly reliable rotating drum for a magnetic recording and reproducing device that does not cause damage.

[Brief explanation of drawings]

FIG. 1 is a side view showing a rotating drum according to an embodiment of the present invention;
Figure 2 is a characteristic diagram showing the relationship between the gap between the heads and magnetic crosstalk, Figure 3 is a characteristic diagram showing the relationship between the gap distance between the two heads and the contact length of the Herad core with the tape.
FIGS. 4 and 5 are side views showing a conventional rotating drum. 1... Head, 2... Head, 3... Head core, 4... Head core, 5... Drum, 6, 7...
Front edge, 8... tape. Figure 2

Claims (1)

[Claims] (1) A rotating drum of a magnetic recording and reproducing device equipped with a plurality of heads that record and reproduce signals of different types in close proximity to each other at the same time, in which a rotary drum is provided between two adjacent heads among the plurality of heads. A rotating drum for a magnetic recording/reproducing device, characterized in that the gap at the closest portion is 1.3 mm or more and 2/3 or less of the gap distance between the two adjacent heads.