JP2560913B2 - Magnetic recording and playback device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is represented by a video tape recorder (hereinafter referred to as VTR), and is recorded by at least two or more tape running speeds such as standard and triple. The present invention relates to a magnetic recording / reproducing apparatus having a mode.

[Prior Art] FIG. 3 is a schematic plan view showing an arrangement example of heads in a conventional VTR. In FIG. 3, (1) is a cylinder drum, (2) and (3) are fixed heads, and these are fixed. The heads (2) and (3) are located on the cylinder drum (1).
The standard mode head (2H
R), (2HL) and triple mode head (6HL), (6H
R) is a combination head.

The standard mode heads (2HR) and (2HL) of the fixed heads (2) and (3) are generally 58 μm and 48 μm, or both of them are 48 μm.
The width is narrower than the standard track width of 58 μm, and the triple mode heads (6HL) and (6HR) are 26-
The width is 33 μm, which is wider than the VHS standard track width of 19.3 μm. The reason for using a head having a width that does not match the track width of the VHS standard is to make special reproduction such as slow stills noiseless and to improve set compatibility.

Further, in FIG. 3, (4) and (5) are movable heads, which are arranged at 180 ° opposite positions on the cylinder drum (1) and are perpendicular to the rotation direction a of the cylinder drum (1). Move. These movable heads (4),
(5) is to move a head up and down by applying a current to a coil by the principle of an electromagnet, or by applying a voltage to a piezoelectric element and expanding and contracting a plate fixed to the piezoelectric element, the head attached to the plate end is moved up and down. It is moved by an actuator (not shown) such as moved. Since it is used only during special reproduction such as slow still, both are L azimuth. Hereinafter, they are referred to as (AT-L) and (AT-L).

 Next, the operation of the above configuration will be described.

As a typical example of special reproduction, FIG. 4 shows a head trace state at the time of still recording in a triple speed recording mode. In this case, the track on the tape of R azimuth 19.3 μm is fixed head (2), The same azimuth heads (2HR) and (6HR) in (3) trace. here,
The reason why the L / R azimuth head does not stop is that in a fast-moving image, the image changes greatly even in 1 / 60th of a second, and a blur occurs in the still image.

In FIG. 4, (6), (8) and (10) are all R
Azimuth, (7), and (9) are L azimuth tracks, and if the standard mode head (2HR) is 58 μm at this time, as shown in FIG. Even though I want to take out the track, the signal next to the track in (6) also opens. Since the adjacent tracks have different azimuth angles, the degree of interference is small, but the adjacent tracks cause large interference. Therefore, the head (2H
R) is generally 48 μm or less.

Further, due to the variation accuracy of the deck of each VTR, which has a large effect particularly in the triple mode, the track (11) on the tape pattern may be bent by 7 μm at the maximum as shown in FIG.

According to the standard, it is within 7 μm, but when bending in the opposite direction to the standard, there will be a maximum difference of 14 μm between decks. In addition, since the trace is performed obliquely during special reproduction, the signal originally becomes small at both ends of the track, and it becomes more difficult to open the signal due to the compatible bend. Therefore, triple mode head (6HL), (6H
R) is generally 26 μm or more, which is wider than 19.3 μm.

Also, when special playback is performed by the movable heads (4) and (5), the track width of the standard mode head (2HR) is narrowed and the triple mode head (6H
Wide track width of L) and (6HR) is not required, and only compatibility during normal playback in triple mode becomes a problem. Up to ± 7
In order to clear the compatibility of μm, the triple mode heads (6HL) and (6HR) can be narrowed down to around 24μm, but it cannot be reduced to 19.3μm.

[Problems to be Solved by the Invention] As described above, in the conventional magnetic recording and reproducing apparatus,
Fixed heads (6HL) and (6HR) in 3x mode cannot be narrowed down to 24μm or less, so strokes from adjacent tracks are spread, resulting in poor image quality compared to recording / playback with a 19.3μm head. was there.

Especially, in the edge part where the brightness changes greatly from black to white, the sideband of FM spreads, so it is difficult for azimuth to get rid of low-frequency crosstalk interference, and noise is easy to get over.
Further, since the color is also converted into the low frequency range and recorded, crosstalk interference from an adjacent track is easily received.

The present invention has been made to solve the above problems, and it is possible to perform recording / reproducing in a triple mode without crosstalk interference and recording / reproducing in a standard mode with good S / N. It is an object of the present invention to provide a magnetic recording / reproducing device that can be used.

[Means for Solving the Problems] A magnetic recording / reproducing apparatus according to the present invention has at least two kinds of recording modes depending on the tape running speed, and is provided so as to face the rotary drum by 180 °, and has two kinds of recording modes. It has a head width equal to or almost equal to the track width of the recording mode, and a combination head composed of a combination of different azimuths, and a position facing 180 ° to the rotating drum so that it can move vertically to the rotating direction of the rotating drum. And a movable head having a head width equal to or nearly equal to the track width of the long-time recording mode among the above recording modes, and at least one of which is composed of a combination head made of different azimuths. is there.

[Operation] According to the present invention, when a tape recorded in triple mode and having poor compatibility is reproduced, normal reproduction can be performed by the combination movable head of the double azimuth. As a result, it is possible to obtain a high-quality reproduced image by using a head having a width that conforms to the standard for self-recording reproduction and compatible tape.

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic plan view showing an arrangement example of heads in a VTR according to an embodiment of the present invention.
Since (1), (2), (3), and (4) have the same configuration as that of the conventional example shown in FIG. 3, corresponding parts are designated by the same reference numerals, and detailed description thereof will be omitted.

1 is different from the conventional example in FIG. 3 in that one movable head (5) is a combination head composed of L and R azimuths, that is, double azimuths (AT-L) and (AT-R). That is the point.

As a result, all special playback is performed with two (AT-L) heads, and incompatible 3x mode playback is performed with (AT-R) in the movable head (5) and (AT-R) in the movable head (4). L) head can be performed, so fixed head (2) (6HL), (2HR) head and fixed head (3) (6HR), (2HL) head should be 58μm and 19.3μm as standard respectively. Is possible. Therefore, in the standard mode, a good S / N signal using a full track can be obtained, and in the triple mode, a good image without crosstalk from adjacent tracks can be obtained.

In practice, taking into account variations in head width and steps during head mounting, the (2H) head is made slightly narrower than 58 μm to prevent overwriting, and the (6H) head is 19.3 μm.
Slightly wider, HiFi due to S / N deterioration and deep recording
It is designed to prevent the voice head from remaining unerased.

Further, since the (AT-L) of the movable head (4) and the (AT-R) and (AT-L) of (5) are movable in the direction perpendicular to the track, how is it in both the standard mode and the triple mode? Even with special reproduction, it is possible to trace without noise with a head width of 19.3 μm.

Fig. 2 shows an example of this, and when it is desired to trace the track (13), the cylinder drum (1) is changed depending on the tape speed.
If it is traced at an inclination of (14), the track (13) can be traced as shown by the diagonal line by gradually moving the head upward as shown by the arrow in the figure. Actually, the head width is selected to be larger than 19.3 μm in consideration of the traceability of the actuator and the S / N aspect, but in principle 19.3 μm is sufficient.

In the above embodiment, only one movable head (5) is a double azimuth combination head, but the other movable head (4) is also a double azimuth combination head. Even in this case, the same effect as that of the above-described embodiment is obtained.

[Effects of the Invention] As described above, according to the present invention, special reproduction and other VTs are performed.
When compatible playback is performed on the tape recorded in R, the standard mode and long-time mode are both in accordance with the standard, according to the recording mode of the video recorded on the tape, without adversely affecting the state of the playback image of both. Since the head width corresponding to the optimum track width can be selected, it is possible to obtain a high-quality reproduced image with good S / N and no crosstalk interference.

Also, at a position facing the rotating drum by 180 °, it is provided so as to be movable vertically to the rotating direction of the rotating drum,
Special reproduction is performed with a combination head that has a head width equal to or nearly equal to the track width in the long-time recording mode, and at least one of the heads is made of different azimuth, so that a good reproduced image can be obtained. it can.

Furthermore, by providing the movable combination head described above, it is possible to reliably trace the recording track even when playing back a tape recorded in a long time mode with another model, and to obtain a good playback image. it can.

In addition, by providing this head, it is possible to optimally perform special playback and playback in incompatible long time mode recorded by other models, so the fixed head width is standard or long time track. It can be set equal to or approximately equal to the width.

Therefore, in the standard mode, recording / playback can be performed using the full track, a signal with good S / N can be obtained, and in the long-time mode, recording / playback can be performed with almost a predetermined track width, It is possible to obtain a good image without crosstalk from the track.

[Brief description of drawings]

FIG. 1 is a schematic plan view showing an arrangement example of heads in a VTR according to an embodiment of the present invention, FIG. 2 is an explanatory view of a trace state of a movable head during special reproduction, and FIG. 3 is a view of a head in a conventional VTR. FIG. 4 is a schematic plan view showing an arrangement example, FIG. 4 is an explanatory view of a trace state when a standard head in the conventional triple mode is still, and FIG. 5 is an explanatory view showing a bent state of a tape pattern. (1) ... Cylinder drum, (2), (3) ... Fixed head, (4), (5) ... Movable head. The same reference numerals in the drawings indicate the same or corresponding parts.

Claims (1)

(57) [Claims] 1. A magnetic recording / reproducing apparatus having a recording mode according to at least two or more kinds of tape running speeds, which is provided to face a rotating drum by 180 ° and has a head width equal to or substantially equal to a track width of the two kinds of recording modes. A combination head having a width and a combination of different azimuths, and a position facing the rotating drum 180 ° so as to be movable perpendicularly to the rotating direction of the rotating drum. A magnetic recording / reproducing apparatus comprising: a movable head having a head width equal to or substantially equal to a track width in a recording mode, and at least one of which is a combination head made of different azimuths.