JPS58205925A - Magnetic recorder and reproducer - Google Patents

Abstract

PURPOSE:To atain a stable output signal at all times, by tracking the servo of a reproducing head against a minute fluctuation in the broadwise direction of a magnetic tape so as to hold the reproducing head at a normal position at all times to a recording track. CONSTITUTION:One reference track 30 is recorded on a magnetic tape 28 by a recording head 1. Further, two servo tracks 31, 32 for reproducing the track 30 are provided on a reproducing head 2, and they are in contact with the respective ridge of the track 30 at the normal position to the track 30. An output signal reproduced with these tracks 31, 32 is processed with a closed loop controlling circuit, and when the track 30 is shifted from the head 2 because of the positional fluctuation toward the broadwise direction of the tape 28, a reproduced output signal corresponding to the signal difference from the tracks 31, 32 is obtained, and a piezoelectric diaphragm 22 is displaced to the normal position to the track 30 by applying this signal to a piezoelectric oscillator 25.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic recording/reproducing device such as a tape recorder.

Generally, in tape running devices such as tape recorders,
It is a necessary condition for realizing good recording and reproducing t6 that the magnetic tape passes near the position of the recording and reproducing magnetic head without any fluctuation in its running position in the middle direction.

By the way, when a magnetic tape manufactured according to a predetermined standard is used as a recording medium, since tape 1J of the magnetic tape is defined by the above standard, the more the number of white tracks in the tape increases, the more the trough increases. 1] needs to be narrowed. Therefore, the amount of variation in the inward running position of the magnetic tape must be reduced in direct proportion to the amount of increase in the number of recording tracks. For this reason, conventionally, at least in a certain section where a magnetic head is arranged, a magnetic tape running path has been developed so that the magnetic tape can run in a running posture without any fluctuation in running position in the 1) direction.
- shows the running position of the magnetic tape in the 11 directions.

A tape guide is provided to control the fluctuation of the However, with existing devices, when the number of recording tracks is increased, it is difficult to control the accompanying variation in the running position of the magnetic tape in the "1" direction without causing any trouble to recording and reproduction.

That is, +l+ of the magnetic tape is caused by the tape guide.
Change in running position in the direction! In order to rapidly control IJ, when a magnetic tape with an inward fluctuation passes through the guide section of the tape guide, the edges of the magnetic tape press against the upper and lower flanges of the guide section of the tape guide. This may damage the edges of the magnetic tape. Damage to the edges of the magnetic tape may have a negative effect on magnetic recording and reproduction.

Furthermore, since the magnetic tape itself has variations in dimensions in the i+ force direction, there is a problem in that the tape guide width cannot be set to a dimension extremely close to the inside of the magnetic tape.

The present invention was made to solve these problems, and by performing servo tracking of the playback head against minute fluctuations in the width direction of the magnetic tape, the playback head is always held at a normal position with respect to the recording track. The green color is used to obtain a stable output signal.

Hereinafter, four embodiments of the present invention will be described with reference to the drawings.

Figures 1, 2, and 3 show the application of the present invention to a magnetic recording/reproducing device for compact cassettes. Figure 1 shows the magnetic tape running system near the recording/reproducing head seen from the magnetic tape sliding surface. FIG. 2 is a front view of A- in FIG.
The A' sectional view and FIG. 3 are top views of FIG. 1.

In FIGS. 1 and 2, the recording head 1 is fixed to a recording head mounting plate 5, and the recording head mounting plate 5 is attached to a subchassis.
A recording head height regulating screw 6 and a screw 9 are screwed to the head 13 by IC. The recording head height regulating screw 6 and the screw 9 are on a plane substantially parallel to the running direction of the magnetic tape 280, and the screw 11 in FIG. The springs 8, 10, and 12 are arranged and loaded respectively (however, although the springs 8, 10, and 12 are not shown, they are loaded in the same state as the spring 10 at the screw 11). ”
- By adjusting the screws 9 and 11, the left and right inclination of the recording head mounting plate 5 (i.e. the recording head 1) and i'J can be adjusted.
The inclination after 11 can be adjusted. In addition, II) the converting head 2' is fixed to the If raw head mounting plate 14, and the reproducing head mounting plate I4 has a piezoelectric vibrator 25 connected to the upper surface.
fL, FE electric moving plate 22 playback head height regulation screw]
5 and screws 18 and 20 (Fig. 3). The playback head height regulating screw 15 and the screw 18 are arranged on a plane substantially parallel to the running direction of the magnetic tape 28, and the screw 2
0 is a spring I7 disposed on a substantially perpendicular plane including the screw 18 with respect to the running direction of the magnetic tape 28, and springs I7 each spring.
．． 19.21 is fitted (however, spring 21
Although not shown, the screw 20 e is inserted in the same manner as the spring 19. ). Above screw 1
By adjusting 8.20, the left and right inclination of the reproducing head mounting plate 14 (that is, the reproducing head 2) and the inclination of the cutting can be adjusted. The screw adjustment holes 23 and 24 on the piezoelectric diaphragm 22 are arranged on the extension line of the screw center axis of the screw 9 and 11, and the adjustment of the screw 9 and 11 from the top surface of the piezoelectric diaphragm 22, that is, the left and right front and back inclinations of the recording head l, can be performed from the top surface of the piezoelectric diaphragm 22. It is configured in such a way that it can be adjusted. Further, the diaphragm 22 is supported by support columns 26 and 27 as shown in the figure.

Here, the magnetic tape 28 traveling in the direction of the arrow in FIG. Rotate the magnetic tape so that the edges are not damaged.
The recording/reproducing head runs without being properly brought into contact with the magnetic tape sliding surface of the recording/reproducing head while being restricted from starting in the l+ direction.

At this time, as shown in FIG. 4, one h (quasi-track 30) is recorded on the magnetic tape 28'2 by the recording head l.On the other hand, on the reproducing head 2 there is a track 30 for reproducing the reference track 30. Two servo tracks 31, 32 are arranged, which partially abut respective edges of the reference track 30 when in their normal position relative to the reference track 30.These servo tracks 31 The output signal reproduced by .32Vc is processed by a closed loop control circuit configured in a Bronch diagram as shown in FIG. When the birth head 2 deviates from the birth head 2 due to the positional change mJ, a birth output signal corresponding to the difference e between the signals S and S2 from the servo tracks 31 and 32 is obtained, and this output signal is used as the previous curse.
By applying a voltage to the piezoelectric vibrator 25, the piezoelectric diaphragm 22 is displaced to a normal position with respect to the reference track 30. As described above, by displacing the piezoelectric diaphragm 22 to which the piezoelectric vibrator 25 is bonded, the reproducing head 2 is displaced in the "1" direction of the magnetic tape 28, thereby returning to the normal position with respect to the reference track 301. It is possible to prevent deterioration of the reproduced output signal caused by minute fluctuations in the middle direction of the magnetic tape, which could not be controlled by conventional tape guides, and to prevent the reference track 30 to be recorded from being By performing servo tracking of only the regenerated yarn in any conventional device, as long as it does not deviate from the above, it becomes possible to always regenerate stable and correct tracks.

As explained above, the present invention is a magnetic recording and reproducing device disposed in the running path of a magnetic tape, and is configured to be able to operate by following the amount of positional fluctuation of the regenerating thread of the magnetic recording and reproducing device. Even if the number of tracks increases, the magnetic tape can always be run under stable playback conditions.

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[Brief explanation of the drawing]

FIG. 1 is a front view of essential parts of an embodiment of a magnetic recording/reproducing device according to the present invention, FIG. 2 is a sectional view taken along line A-A', FIG. 3 is a top view, and FIG. 4 is a servo tracking FIG. 5 is a schematic diagram showing the relative positions of the reference track and the servo track in FIG. 5, and a block diagram of the servo tracking circuit in FIG. ' In the figure, 1: recording head, 2: reproducing head, 3.4: tape guide, 22: piezoelectric diaphragm, 25: piezoelectric copying element, 28
: Magnetic tape, 29: Compact cassette half, ao
:H semi-track, 31, 32: Servo track.

Claims (1)

[Claims] 1. A magnetic reproducing head independently suspended on a piezoelectric diaphragm to which a piezoelectric vibrator is bonded, a servo track containing the magnetic reproducing head, and a reference track recorded on a magnetic tape on the servo track. means for moving the Vf and the electric vibration damping vibrator based on the signal detected by the pressure 1;
A magnetic recording/reproducing apparatus characterized in that the magnetic reproducing head is displaced to an appropriate position by μs<mJ of an F oscillator.