JPS6317058Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a magnetic head height adjustment device suitable for application to a magnetic recording device that records, for example, digital signals on a magnetic tape using a pair of parallel rotating magnetic heads. .

BACKGROUND ART AND PROBLEMS Conventionally, a magnetic recording device as shown in FIG. 1 has been proposed as a magnetic recording device for recording video signals on a magnetic tape using a rotating magnetic head. That is, in FIG.
1 is a rotating shaft, 2 and 3 are bearings that rotatably support the rotating shaft 1, 4 is a bearing housing, and 5 is a lower fixed drum located below the drum disk 7 attached to the rotating shaft 1. , 6 is an upper fixed drum located above the drum disk 7. Further, 8a and 8b indicate rotating magnetic heads fixed at predetermined positions on the drum disk 7 at 180° angle intervals (see Fig. 2), and these rotating magnetic heads 8a and 8b are centered in a direction perpendicular to the direction of rotation. They have so-called different azimuths in which the directions of the gaps are tilted to opposite sides by a predetermined angle, for example, 7 degrees. Further, 9 is a support member for fixing the lower fixed drum 5 and the upper fixed drum 6, and 10 is a rotary transformer fixed to the lower side of the drum disk 7 and rotating together with this drum disk 7.
The rotor of the RT, 11, is a rotary transformer RT fixed to the upper side of the lower fixed drum 5, facing the rotor 10.
12 is the stator of the motor M mounted on the end of the lower fixed drum 5; 13 is the stator 12;
A motor M fixed to one end of the rotating shaft 1 corresponds to
The rotors 14 and 15 are respectively attached to the upper fixed drum 6,
This is a tape guide for guiding the winding of the magnetic tape MT around the drum disk 7 and lower fixed drum 5. In this magnetic recording device in which the rotating magnetic heads 8a and 8b are fixed at predetermined positions on the drum disk 7 at 180° angle intervals, the rotating transformer RT
Video signals for each field are alternately supplied to the rotating magnetic heads 8a and 8b via the stator 11 and rotor 10, and the video signals are recorded on the magnetic tape MT by the rotating magnetic heads 8a and 8b. In this case, tracks T _{a and} T _b of video signals are formed adjacent to each other obliquely with respect to the width direction of the magnetic tape MT as shown in FIG. 3, and these tracks T _a and T _b have different azimuths. Recording is carried out by the rotating magnetic heads 8a and 8b, so-called inclined azimuth recording. By recording the inclined azimuth in this way, the tracks T a and T _a are adjacent to each other.
If T _b is formed, even if a track shift occurs during playback, the signals from the adjacent tracks are recorded by rotating magnetic heads with different azimuths, so the signals from the adjacent tracks that are scanned due to the track shift will be ignored. The amount of signal pickup (crosstalk) can be kept small. Therefore, even without providing a guard band between the tracks,
This had the advantage that tracks could be placed adjacent to each other and recorded at high density.

However, in the conventional magnetic recording device constructed in this manner, if the rotating side race surfaces 2a and 3a of the bearings 2 and 3 that rotatably support the rotating shaft 1 to which the rotating magnetic heads 8a and 8b are integrally attached are tilted, the bearings 2 and 3 create undulations,
The rotating magnetic heads 8a and 8b, which are integrally attached to the rotating shaft 1, rotate while vibrating in different vertical directions. Therefore, although the adjacent tracks should originally be formed parallel to the magnetic tape MT as shown in FIG. 3, the adjacent tracks T _a and T _b become different meandering curves as shown in FIG. 4. The track widths of tracks T _a and T _b fluctuate, and when this fluctuation becomes large, track missing occurs. Therefore, when a magnetic tape MT with such track width fluctuations and track missing occurs is played back, the output level of the reproduced signal changes. decreases and S/N
The disadvantage was that the ratio decreased.

In view of this, a magnetic recording apparatus as shown in FIGS. 5, 6, and 7 has been proposed as a magnetic recording apparatus designed to eliminate the adverse effects caused by the waviness of the bearing of the rotating shaft of the rotating magnetic head. Furthermore, this fifth
In the figures, FIGS. 6 and 7, parts corresponding to those in FIGS. 1 to 4 are denoted by the same reference numerals, and detailed explanation thereof will be omitted.

In FIG. 5, reference numerals 8c and 8d indicate a pair of rotating magnetic heads having different azimuths, and the rotating magnetic heads 8c and 8d are located at approximately the same position with respect to the rotational direction, and are sufficiently small with respect to the rotational direction of the drum disk 7, for example. They are attached at an angular interval θ of, for example, 1°. In this case, the head substrate 16 to which the magnetic heads 8c and 8d are fixed has a slotted shape, for example, as shown in FIG.
A rotating magnetic head 8 is attached to each end of the two protrusions of the
c and 8d are fixed. Further, this head board 16 is attached to the drum disk 7 by screws 17. Further, a rotating magnetic head 8c is mounted at a predetermined position on the protrusion of the head substrate 16.
and a screw 18 for independently adjusting the height of 8d.
a and 18b are provided, respectively. Further, the height adjustment of the rotating magnetic heads 8c and 8d is performed by adjusting the height of the rotating magnetic head 8d, for example, which is located on the front side with respect to the traveling direction of the magnetic tape MT, by (track pitch) x (with respect to the rotating shaft 1 between the rotating magnetic heads 8c and 8d). Angular interval θ)
Adjust it to be lower than the rotating magnetic head 8c by ×1/360. Here, the track to be recorded on the magnetic tape MT is
When the inclination angle of T _a and T _b is θ ₁ , the magnetic tape
The rotational speed of the rotating shaft 1 and the moving speed of the magnetic tape MT are set so that when the MT moves by (track width)/sin θ ₁ , the rotating shaft 1 rotates once. Then, the time axis of the digital signal obtained by converting the video signal for each field into PCM is compressed to one half, and the signal is sequentially and alternately supplied to the rotating magnetic heads 8c and 8d every rotation of the rotating shaft 1. do.

According to the configuration of this example, a digital signal whose time axis is compressed by half for each rotation of the rotary shaft 7 is transmitted to the rotary magnetic heads 8c and 8d via the rotary transformer RT.
These time-base compressed digital signals are sequentially and alternately supplied to the rotating magnetic heads 8c and 8d.
As shown in FIG. 3, tracks are recorded on the magnetic tape MT alternately in a tilted azimuth manner one track at a time.

In this example, the rotating side race surfaces 2a of the bearings 2 and 3 serve as bearings that rotatably support the rotating shaft 1 to which a pair of rotating magnetic heads 8c and 8d are attached.
and 3a are tilted and waviness occurs in the bearings 2 and 3, the rotating magnetic heads 8c and 8d
Although the track pattern recorded on the magnetic tape MT with an inclination azimuth is curved as shown in FIG. 8, the track width can be kept constant and the parallelism of adjacent tracks T _a and T _b can be maintained. Therefore, by detecting the tracking deviation of the magnetic tape MT of the rotating magnetic head and correcting the deviation for reproduction, it is possible to obtain a good reproduction signal without reducing the S/N ratio. can.

In this way, according to this example, the two rotating magnetic heads 8c and 8d with different azimuths are provided at approximately the same position in the rotational direction, and each time the two rotating magnetic heads 8c and 8d make one rotation, Since tilt azimuth recording is performed alternately on the magnetic tape MT one track at a time, even if the rotating side race surfaces 2a and 3a of the bearings 2 and 3, which serve as bearings for the rotating shaft 1, are tilted, the tilted azimuth is recorded on the magnetic tape MT. Tracks T _a and T _b that are parallel to each other and have a constant track width can be formed by azimuth recording, so fluctuations in track width and track missing can be eliminated, and reproduced signals can be obtained without reducing the S/N ratio during reproduction. be able to. Incidentally, according to this example, good recording can be easily achieved even in high-density recording with a narrow track width of 10 μm or less.

Furthermore, although a slotted head substrate 16 is used in the above example, a substantially T-shaped head substrate as shown in FIGS. 9 and 10 has also been proposed. Here, 18 is the above-mentioned example 18a, 18
This is a height adjustment screw similar to b.

Further, when one of the magnetic heads 8d in the above example is used as a reproducing magnetic head, and the head gap length of the recording magnetic head 8d is _L1 , and the head gap length of the reproducing magnetic head 8c is _L2 , _L1 < _L2 . Some devices are arranged in pairs to ensure that the reproducing head 8c scans over the recording track during reproduction, thereby obtaining a good reproduction output.

However, such a pair of magnetic heads 8c,
In the case of a configuration in which the magnetic heads 8d are arranged in parallel at predetermined positions, for example, in the example shown in FIG. 5, the shape of the head substrate 16 is devised, and then the work of mounting the head substrate 16 on the drum disk 7 and the magnetic heads 8c, 8d are performed.
It is necessary to independently adjust the adjustment screws 18a and 18b. In the example shown in FIG. 9, the work of mounting the head board 16 at a predetermined position on the drum disk 7 after devising the shape of the head board 16 and the work of selecting the magnetic heads 8c and 8d of the desired height are performed. magnetic head 8c,
The work involved in adjusting the height of the 8d was troublesome and caused problems.

Purpose of the invention In view of these points, the present invention reduces the number of parts.
It is an object of the present invention to provide a magnetic head height adjusting device that allows easy adjustment of the magnetic head height.

Summary of the invention The magnetic head height adjustment device of the present invention has a long hole approximately at the periphery of the drum disk whose longitudinal direction is tangential to the drum disk periphery, and a long hole extending from the middle of the long hole to the outer periphery of the drum disk. It has notches that overlap each other in the vertical direction, and by adjusting the interval between the notches, the height of a pair of magnetic heads fixed at predetermined positions on the left and right sides of the notches can be adjusted. , the number of parts can be reduced and the height of the magnetic head can be easily adjusted.

Embodiment Hereinafter, an embodiment of the magnetic head height adjusting device of the present invention will be described with reference to FIGS. 11 and 12. In FIGS. 11 and 12, parts corresponding to those in FIGS. 6 and 7 are designated by the same reference numerals, and detailed explanation thereof will be omitted.

In the present invention, the magnetic heads 8c and 8d are directly fixed to predetermined positions on the drum disk 7 using a jig or the like, without using the head substrate 16. In this example, an elongated hole 7a is provided approximately at the periphery of the rotating drum 7, the longitudinal direction of which is tangential to the periphery of the head drum. Furthermore, a notch 7b having a predetermined thickness and an inclination of 45 degrees, for example, is provided from the middle of the elongated hole 7a to the peripheral edge of the drum disk 7, as shown in FIGS. 11 and 12. and,
A tapered screw 19 with an elliptical cross section and a tapered shape as shown in FIG. 12 is inserted as a height adjustment screw for the magnetic heads 8c and 8d from the periphery of the drum disk toward the center, and the taper screw 19 is rotated by a predetermined angle. When the magnetic heads 8c and 8d are rotated, there is a difference in relative height between the pair of magnetic heads 8c and 8d as shown by arrow a. The other parts are configured in the same manner as before.

Since the present example is constructed in this way, the head board 16 is not required and the number of parts can be reduced, and the height of both the magnetic heads 8c and 8d can be adjusted at the same time by the rotation of the tapered screw 19 having an elliptical cross section. There is an advantage that the height of the heads 8c and 8d can be easily adjusted.

Further, FIGS. 13 and 14 show other embodiments of the present invention. In FIGS. 13 and 14, parts corresponding to those in FIGS. 11 and 12 are given the same reference numerals, and detailed explanation thereof will be omitted.

In this example, the heights of the magnetic heads 8c and 8d are adjusted using tapered long screws 20. This tapered long screw 20 is connected to the notch 7 of the drum disk 7.
The tapered portion 19a is in contact with b, and the threaded portion 19b at the tip thereof is inserted into a threaded hole 7c for a tapered long screw 20 provided in the drum disk 7. 14, when this tapered long screw 20 is screwed in, the magnetic head 8
The magnetic heads 8c and 8d are moved in the direction of the arrow a, respectively, and the magnetic heads 8c and 8d are adjusted to desired heights. It is easy to understand that this example also provides the same effects as the example shown in FIG. 11.

Further, FIGS. 15 and 16 show other embodiments of the present invention. In FIGS. 15 and 16, parts corresponding to those in FIGS. 11 and 12 are designated by the same reference numerals, and detailed explanation thereof will be omitted.

In this example, a key-shaped cutout groove 7d as shown in FIG. 16 is provided from near the middle of the elongated hole 7a to the outer peripheral edge of the drum disk 7. Then, a magnetic head height adjusting screw 7e is provided, and when screw 7e is screwed in in the direction of arrow b, the magnetic heads 8c, 8d
so that the relative height of is displaced in the direction of arrow a.
It is easy to understand that the example of FIG. 15 also provides the same effects as the above-mentioned example.

Effects of the invention As described above, according to the invention, the number of parts of the magnetic head height adjustment device can be reduced, and the magnetic head height adjustment device can be easily adjusted. .

[Brief explanation of drawings]

Fig. 1 is a sectional view showing an example of a magnetic recording device, Fig. 2 is a sectional view showing an example of a magnetic recording device;
The figures are line diagrams showing the main parts of the example in Figure 1, Figures 3 and 4.
The figure is a diagram for explaining the operation of the example in Figure 1, Figure 5 is a diagram showing an example of a magnetic recording device in which two magnetic heads are arranged side by side on a drum disk, and Figures 6 and 9 are diagrams for explaining the operation of the example in Figure 1, respectively. 7 is a cutaway plan view showing an example of a magnetic head height adjustment device, FIG. 7 is a sectional view taken along the line -- in FIG. 6, and FIG. FIG. 10 is a cross-sectional view taken along the line -- in FIG.
1 is a side view of the example in FIG. 1, FIGS. 13 and 15 are plan views showing other embodiments of the present invention, and FIGS. 14 and 16 are side views of the example in FIGS. 13 and 15, respectively. be. 7 is a drum disk, 7a is a long hole, 7b is a notch, and 19 is a tapered screw.

Claims (1)

[Scope of utility model registration request] An elongated hole whose longitudinal direction is in the tangential direction of the drum disk periphery is formed substantially on the periphery of the drum disk, and cutout portions that overlap each other in the vertical direction of the drum disk from near the middle of the elongated hole to the outer periphery of the drum disk. and the height of a pair of magnetic heads fixed at predetermined positions on the left and right sides of the notch is adjusted by adjusting the interval between the notches. Device.