JPS5990230A - Rotary magnetic head device - Google Patents

Abstract

PURPOSE:To improve operation efficiency during manufacture and to suppress a change in fitting position with time by forming an inflection oscillator in a torus or elliptic ring shape, and reducing the bending rigidity of a magnetic head attachment part. CONSTITUTION:The inflection oscillator 3 performs inflection oscillation having the fixed end at an inflection oscillator attachment part 6. Namely, the optimum tracking state of the oscillator 3 is known by controlling an applied voltage. The oscillator 3 in the torus shape, so the effective length of the oscillator is made longer than that of a rectangular oscillator as much as possible, so large displacement is realized. Further, the bending rigidity of the part where a magnetic head 4 is attached is reduced, so enough displacement is obtained by a small voltage and piezoelectric ceramic plates 1 and 2 are reduced in thickness to improve operativity. The inflection oscillator 3 is held at two points, so a shift in the attachment position of the oscillator 3 with time is suppressed.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention is a rotating head type magnetic recording/reproducing device such as a VTR, which is equipped with a means for the magnetic head to automatically track the recording trunk when 71J is generated. The present invention relates to a rotating magnetic head device.

(Conventional structure and its problems) Generally, in a rotating head type magnetic recording/reproducing device, the rotating magnetic head must accurately trace the recording trunk on the magnetic tape during reproduction.

Instead, a control signal is recorded on the magnetic tape during recording, and during playback, the signal is recorded on the magnetic tape and the magnetic head using the 1/1 signal. It controls the digit C. However, due to reasons such as expansion and contraction of the magnetic tape and differences between the recording device and the reproducing device 4, the magnetic node may not be able to accurately trace the recording track. Also, 1 trade i +L, 1i
Even at low speed playback and high speed playback, the running speed of the magnetic tape is different from the recording speed, making it impossible to control accurately. , both (&: lj, the noise becomes noticeable and difficult to see.

To conclude, the magnetic gutter is automatically moved by the center pressure of the recording track! - JI racking function,
A rotary magnetic gutter device with a rotary structure was proposed.

This divine rotating magnetic device from UL has a magnetic head attached to both ends of a bending vibrator made of two FT4 piezoelectric ceramic plates bonded together, and a magnetic head placed on a rotating cylinder.
i1 Take the medium heat of the oscillator coaxially and turn the pressure to 7.
By applying JE to the Fi magnetic field, the height of the magnetic throat was changed.

However, with such a conventional rotating magnetic head device, the radius of the rotating cylinder is small, and bending vibration is
Since it is not possible to increase the length of r, the magnetic force required to achieve the optimal dragging condition is
・In order to measure -, the thickness of the piezoelectric ceramic plate should be 1'7j! Therefore, if it is difficult to add a piezoelectric ceramic plate, it is difficult to add a piezoelectric ceramic plate to the bending vibrator. When attaching the magnetic throat and inserting the bending vibrator into the rotating cylinder, break the bending vibrator.
M work efficiency is low by 1. -On the other hand, considering the ease of handling, the bending vibrator's height has been increased! If the voltage is increased, the applied voltage required to achieve the optimal)/lasoki/g condition becomes thicker, resulting in deterioration of the polarity of the piezoelectric ceramic plate. Furthermore, in the case of a rectangular bending vibrator, since the rotation/insertion into the ring (= I) is done in one place, the position of the magnetic throat on the rotating cylinder changes over time, etc. Magnetic head devices have one particular drawback.

(Objective of the Invention) The present invention has been made in view of the drawbacks of the conventional example described above, and it improves the efficiency of processing, assembly, W/11 alignment, etc., and also improves the temporal change in the position of the magnetic head. JJIi provides a rotary magnetic head device that can suppress 11-.

(Structure of the Invention) In order to achieve the above object, the present invention forms a bending vibrator in the shape of an annular ring or an elliptical ring, and reduces the bending rigidity of the magnetic head holding portion facing the 100 mm. It is something.

(Description of Examples) Hereinafter, practical examples of the present invention will be explained in detail with reference to the drawings. FIG. 1 is a diagram showing the 4ffi configuration of Jn1 song vibration used in one embodiment of the present invention. In Figure 1,
1 is a first piezoelectric ceramic plate in the shape of an elliptical puff (with one electrode formed on its main surface); 2 is a first piezoelectric fill I; :4 Similar to Kari 1,
It is polarized in the I'7 direction and has an electrode formed on its main surface, and has a shape in which a part of the -II of the 4&+ annular ring facing the -II and J is cut out, respectively. the second piezoelectric ceramic plate, the first 11. A second pressure plate 1 (1) and a ceramic plate 2 are attached to the electromagnetic plate 1 so as to face each other to form an E1 curved vibration r:3. At this time,
Bending oscillator: J is placed in the notch of the second piezoelectric ceramic plate 2 at a position facing r=I in the first piezoelectric ceramic plate 1.
A dented area occurs, and the bending rigidity of this area is noticeably lower than that of other areas. A 6B air nozzle 4 is attached to the porcelain plate 1 in this first area facing each other.

Part 1 of 1. A bending vibration device equipped with a magnetic head 4.
FI + child 3 jX Figure 2 (a) and (b),
As shown, it is attached to the rotary / cylinder 5 (':j). 16″
In addition, there is a bending 1111 transducer with a screw in the center of the circle between the two magnetic throats. The parts are held by screws 7 in the bent parts 6 of the bending stationary element.

bending vibrator: 3] and second piezoelectric ceramic plate 1
and 1 and 2 are pasted together with the polarization directions the same, and as shown in FIG. ．． By applying electric currents 11- of different polarities to the terminals 8b connected to the inner electrodes that are in contact with the electrodes, bending vibrations are generated. -3 is bending 1. As a result, the magnetic head 4 is displaced.

In the above configuration, in this embodiment, 1, 2 (musical vibration r-3
J11 music oscillator removal A (J part () holder fixed D::A
Bending vibration is performed using VCl. That is, /+il 1llll
If you apply the mover 3 Vc electric moon to 4, the magnetic / -node 4 will be attached according to its size, and the 811 minute will be displaced, so the application 71, the best 1 ranking for JT control. You can get the status. Here, since the bending vibration r3 of this embodiment is a conical shape, the effective length of the bending vibrator can be made longer than the 'Xli type bending vibrator from 1971, and the same voltage A larger displacement can be obtained with a relatively small voltage.Since the bending stiffness corresponding to i% of attaching the additional pressure and magnetic/\RAD 4 is reduced, a relatively small voltage can be used to generate sufficient magnetic force to obtain the optimum tracking condition. - Since a displacement of 1 to 4 can be obtained, the noisiness of the piezoelectric ceramic plates 1 and 2 can be improved.
< L, workability during manufacturing can be improved.

Since the bending oscillator is held at two points, the change in position over time in the bending vibration Il'y of I1 is almost completely different from that of a cow.

The bending vibrator 3dX of this example is
It': 11. Although the magnetic plates 1 and 2 are pasted together with their respective polarization directions in the same direction, they can also be constructed with their respective polarization directions reversed.

1. In this example, the 111 curved movator: 3 is a circular ring, but it is made into an elliptical ring, and its major axis is 73 times (with the magnetic -\・I do placed at 6). A similar effect can be obtained by using the bending vibration -j' created by tf9. The moon that is determined to be ``L-loving'' without changing - the thickness of the electromagnetic plate is thick, and the mortar I J
JII ′r1r.

Since the pressure can be reduced, manufacturing jlffi f
The workability and reliability V1 of the bending vibrator at -1- and the reliability of the bending vibrator at -1- and the rotational speed of the bending vibrator
It is highly accurate and provides a significant improvement in quality.

[Brief explanation of the drawing]

FIG. 1 shows yr11+ used in one embodiment of the present invention.
The perspective views of the 111 vibrator, FIGS.
-It is 1'78I.

Claims (1)

[Claims] Annular size: 141 Annular first Ll: On the electromagnetic plate,
If the first H' electromagnetic plate is annular, the UJ shape and size are such that mutually opposing portions are cut out.
1. A bending vibrator formed by pasting an electromagnetic plate, which has a shape in which mutually opposing portions of the long axis of the elliptical ring are cut out, and The magnetic helenoid 1 attached to the notch part of the second piezoelectric ceramic plate facing each other and the bent 1 slider 1ffl are connected to the circumference 111 of the annular or elliptical Ill shape.
S records (keep each on a medium heat for 1 ゛ time) (, 1
A rotating magnetic head device characterized by: