JPH0279209A - Magnetic head moving device - Google Patents

Abstract

PURPOSE:To correct a posture error due to a mechanical fitting by adding the adjusting mechanism to adjust an azimuth angle and the fluttering angle of a head to the title head moving device. CONSTITUTION:When a magnetic gap is formed at the clearance between a center yoke 5 and an outer yoke 7, a driving coil 10 is arranged and the current is supplied to the driving head 10, a bobbin 15 and the driving coil 10 are displaced in a shaft direction and a head 1 is also displaced in the axial direction integrally with the bobbin 15. Auxiliary coils 11 and 12 for the head azimuth angle adjustment and the head fluttering angle adjustment are fitted to the bobbin 15, the current supplied to the auxiliary coils 11 and 12 is adjusted and the azimuth angle and fluttering angle of the head are adjusted. Thus, the posture of a magnetic head 1 supported movably is easily adjusted and the recording and reproducing performance of the signal is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an attitude adjustment device for a magnetic head movably supported.

[Conventional technology]

As a magnetic head moving device used for special reproduction purposes of conventional helical scan VTRs, Japanese Patent Application Laid-Open No. 63-5681
A device such as that described in Publication No. 0 has been considered.

In this device, a bobbin (cylindrical frame) around which an electromagnetic coil is wound is supported movably in the axial direction of the cylinder by two leaf springs. The coil is placed in a magnetic gap of a magnetic circuit including a permanent magnet, and the electromagnetic force generated by energizing the coil causes the coil and bobbin to be displaced in the cylindrical axis direction.

The head is attached to move together with the bobbin, and when the bobbin is displaced, the head is also displaced in the same way. Therefore, by energizing the coil, the head is displaced in the axial direction of the cylinder. The entire device for displacing this head is attached to a rotating drum (rotating cylinder) of a drum (rotating magnetic head device) of a helical scan VTR, and the head moves in the direction of the rotation axis while rotating.

[Problem to be solved by the invention]

As is well known, in a magnetic recording/reproduction device, in order to perform good recording or reproduction, the attitude of the head (head azimuth angle, head tilt angle) must be adjusted when the head contacts the tape.
It is important to keep it correct, and this is particularly important in high-density recording.

However, in the device described in Japanese Patent Application Laid-Open No. 63-56810, the head is attached to a movably supported bobbin via a mounting plate, so its position and posture can be maintained with high accuracy. This is difficult to do with the apparatus described, and it is extremely difficult to maintain the head azimuth angle and head tilt angle with high accuracy.

[Means to solve the problem]

In view of the above points, the present invention has been developed based on the azimuth angle of the head,
By adding an adjustment mechanism for adjusting the tilt angle to the head moving device, it is possible to correct posture errors caused by mechanical attachment.

[Effect]

Specifically, an auxiliary coil for adjusting the head azimuth angle and head tilt angle is attached to the bobbin, and the azimuth angle and tilt angle of the head are adjusted by adjusting the current supplied to the auxiliary coil.

〔Example〕

An embodiment of the present invention will be described based on FIGS. 1 to 4. This embodiment is an example in which the present invention is applied to head azimuth angle adjustment. FIG. 1 is a sectional view of a head moving device of the present invention, and FIG. 2 is an external view thereof.

The left half of FIG. 1 is a sectional view including the head of the device, and the right half is a sectional view in a direction perpendicular to this.

6 is the lower yoke, which has a roughly disk-like shape, with ribs protruding on both sides as shown in Figure 2.A hole is provided in this part for attaching the head moving device to the rotating cylinder. It is provided. A circular hole is provided in the center of the lower yoke 6, and a cylindrical permanent magnet 3 is fitted into this hole and bonded. A cylindrical center yoke 5 is bonded to the permanent magnet 3 concentrically therewith. Reference numeral 7 denotes an outer yoke, which is supported by fitting with the lower yoke 6. Reference numeral 4 denotes an upper yoke, which has a disk shape, and a permanent magnet 2 is fitted into a circular hole in the center and is bonded to the upper yoke.

The lower yoke 6, the outer yoke 7°, the upper yoke 4, and the center yoke 5 are made of a high magnetic permeability material, and together with the permanent magnets 2 and 3, form a component of a magnetic circuit. As a result, a magnetic gap is formed between the outer circumferential portion of the center yoke 5 and the inner circumferential portion of the outer yoke 7, and this portion is maintained at a high magnetic flux density. The drive coil 10 is arranged in this part. The drive coil 10 is wound around the outer periphery of a cylindrical bobbin 15. The bobbin 15 has two leaf springs 8,
9 are attached via attachment members 16 and 17, and the outer peripheral portions of the leaf springs 8 and 9 are fixed to the outer yoke 7. Therefore, the bobbin and the drive coil are supported by two leaf springs and are movable in the direction of the central axis. The head 1 is fixed to an extension of the leaf spring 8 and protrudes through a hole bored on the outside of the head moving device. This is the second
This is shown in the external view of the figure.

When a current is supplied to the rotating coil 10, the driving coil 10 receives an electromagnetic force in the direction of the central axis based on the principle of a speaker, and this force causes the bobbin 15 and the driving coil 10 to be displaced in the axial direction. As a result, the head 1 also moves together with the bobbin 15 and is displaced in the axial direction. This displacement corrects mistracking during search or slow playback to obtain good slow and search images.

This embodiment is intended to add an azimuth angle correction mechanism for the head 1 to the above-described head moving device. For this purpose, auxiliary coils 11,12 are connected to the head 1 as shown in FIG.
Attach the bobbin to the bobbin 5 at a 90° angle with the bobbin. Although only two auxiliary coils, auxiliary coils 11 and 12, are shown in FIG. 1, two other auxiliary coils 13 and 14 are installed at positions 180 degrees apart from these auxiliary coils. The shape and mounting position of the auxiliary coils 13, 14 will be explained with reference to FIGS. 3 and 4.

FIG. 3 is a diagram showing a state in which a coil is attached to the bobbin 15. The rotating coil 10 is wound concentrically around the outer periphery of the bobbin 15. As shown in the figure, the auxiliary coils 11 and 12 are
The coil is wound into a rectangular shape with a center section open, and after being hardened into this shape, it is attached to the bobbin 15. In addition, these auxiliary coils are printed and wired directly on the plastic film that is the material of the bobbin 15, like a flexible board.
This film may be wound into a cylindrical shape to form a bobbin and placed in the position shown in the figure.

An auxiliary coil 13 is located on the opposite side of the auxiliary coil 11 at an angle of 180°, and an auxiliary coil 13 is located opposite the auxiliary coil 11 in the figure.
An auxiliary coil 14 is attached to the opposite side separated by an angle of 80'. All of these auxiliary coils have the same shape.

Figure 4 shows the state in which the leaf spring 8.9 is attached to the coil and bobbin assembly. As shown in the figure, when the head 1 is placed at the center, the auxiliary coils 11, 12, 13, and 14 are attached to the left and right sides, respectively, at positions rotated by 90 degrees.

As shown in FIG. 1, the lower side of the rectangularly wound auxiliary coil 11 is located at the magnetic gap 80, and the upper side is located away from the magnetic gap 80.

Regarding the auxiliary coil 12, its upper side is the magnetic gap 8.
0 part, and the lower side is located away from 80 parts of the magnetic gap.

The auxiliary coil 13 is located at the same height as the auxiliary coil 11,
The auxiliary coil 14 is located at the same height as the auxiliary coil 12 and has the same positional relationship as 12 with respect to the magnetic gap 80 .

Each of these four auxiliary coils is marked with an arrow 20.21.
, 22 and 23, the current flows clockwise in the portion of the auxiliary coil 11 located within the magnetic gap 80 when viewed from above. Similarly, current flows clockwise in the portion of the auxiliary coil 12 located within the magnetic gap 80. On the other hand, the current flows counterclockwise in the portion of the auxiliary coil 13, 14 located within the magnetic gap 80. Since the other parts of the coil are not located in the magnetic gap 80, they receive only a small amount of electromagnetic force and can be ignored. Therefore, if auxiliary coil 11 receives an electromagnetic force in the direction of arrow 3o, auxiliary coil 12 also receives electromagnetic force as shown by arrow 31.

Since the direction of the current is opposite to the auxiliary coil 13, the auxiliary coil 13 receives an electromagnetic force in the direction opposite to that of the so-called arrow 30 indicated by the arrow 32. Auxiliary coil 14 similarly receives electromagnetic force in the direction indicated by arrow 33. If these coils are identical and have exactly the same position relative to the magnetic gap, then the electromagnetic forces experienced by these coils are all equal. The coil and bobbin assembly is therefore subjected to forces as indicated by arrows 30, 31, 32, and 33. The coil and bobbin assembly are supported by leaf springs 8 and 9. Therefore, the coil and bobbin assembly receives a clockwise bending moment when viewed from the head side. Coil and bobbin assembly are parallel 2
Since it is supported by two leaf springs, it has high rigidity against bending moments in this direction, but when viewed from the head side, it is slightly displaced in the direction of clockwise rotation. As a result, since the entire head moving device is fixed to the cylinder, only the head rotates and the equivalent head azimuth angle changes slightly.

To reverse this change in azimuth angle, use arrow 20.
, 21, 22, and 23 may all be reversed. That is, the equivalent azimuth angle can be adjusted by changing the direction and magnitude of the current.

In the above embodiment, four auxiliary coils 11, 12, 13
．． Although 14 are provided, as is clear from the above description, it is possible to reduce this number. For example, the azimuth angle can be adjusted without the auxiliary coils 11.13 and only with the auxiliary coils 12.14. Also, auxiliary coil 11,1
Even if only one of 2, 13, and 14 is used, the azimuth angle can be adjusted.

Next, another embodiment of the present invention will be described based on FIG. This embodiment is an example in which the present invention is used to adjust the tilt angle of the head. FIG. 5, like FIG. 4, shows a state in which the leaf spring is attached to the coil bobbin assembly. The difference between the embodiment shown in FIG. 4 and the embodiment shown in FIG. 5 is that in FIG.
Auxiliary coil 41.4 centered at the same angle (radial position) as
2 is fixed to the bobbin 15. Although not shown in the figure, an auxiliary coil 43 is attached at a position opposite to the auxiliary coil 41 by 180 degrees, and an auxiliary coil 44 is installed at a position opposite to the auxiliary coil 42 by 180 degrees.

That is, these auxiliary coils 41, 42, 43, 44
The auxiliary coils 11, 12, 13, and 14 are moved to positions rotated by 90'' about the central axis of the bobbin 15.

The method of energizing these auxiliary coils 41, 42, 43, 44, and the electromagnetic force they receive differs only in position by 90 degrees; in all other respects, the auxiliary coils 11, 12, 1, respectively.
Same as 3.14. Therefore, the coil bobbin assembly receives a moment 1- in a direction that changes the tilt angle of the head (the angle formed by the tangential plane of the tape sliding surface of the head and the tape surface). Therefore, by adjusting the value and direction of the current supplied to the auxiliary coils 41, 42, 43, and 44, as in the case of adjusting the azimuth angle described above, the head tilting angle can be adjusted and the best head touch can be obtained. can.

In this embodiment, not only the tilt angle of the head but also the height of the head is changed.
By adjusting the current flowing through the

Can be corrected.

FIG. 6 shows a configuration example of a parking circuit for operating the magnetic head moving device shown in FIG. 5 above. In FIG. 6, the inside surrounded by the two-dot chain line shows the part on the rotating side, and the other parts show the fixed side. A control signal supplied from the control circuit 50 is supplied to the brush 53a via the rotation circuit 51.

The brush 53a is in contact with a slip ring 54a on the rotating side, and the drive coil 10 is connected to the slip ring 54a. The other end of the drive coil 10 is a slip ring 5
4b, the slip ring 54b is in contact with the fixed brush 53b, and the brush 53b is grounded. The drive current according to the control signal is applied to the drive coil 10.
When the head 1 is supplied, the head 1 is displaced accordingly. A power source 55 is installed on the fixed side as a power source for the current supplied to the auxiliary coil.
is arranged, and power is supplied to the rotating side via the brush 53c and slip ring 54c. Auxiliary coil 11,1
2, 13, and 14 are connected in series as shown in the figure, and are connected to the power supply via a variable resistor 58. The other end of the coil is grounded. Auxiliary coil 11. ．． 1
2, 13, and 14 are controlled. Auxiliary coils 41, 42, 43, 44 are also auxiliary coils 11, 12, 1
They are connected in series in exactly the same way as in 3.14, and the current is controlled by a variable resistor 59.

Further, as shown in FIG. 1, the power source 55 can also serve as a power source for a preamplifier 57 on the rotation side.

A reproduction signal from the head 1 is amplified by a preamplifier 57 and transmitted to the fixed side by a rotary transformer 56.

Although only one head is shown in FIG. 6, it is obvious that this diagram can be expanded and explained even if there are a plurality of heads or head moving devices. According to this embodiment, even if the number of head moving devices increases, the increase in the number of slip rings and brush channels can be suppressed to a minimum. In other words, even if the number of head moving devices increases by one, the brushes and slip rings (53a and 54 in the figure) connected to the drive coil 10
(equivalent to a) need only be increased by one, and all adjustments to the current supplied to the other auxiliary coils can be performed by the circuit provided on the rotating side. The number of slip ring channels has also been reduced by sharing the preamplifier power supply and auxiliary coil power supply.

The azimuth angle, tilt angle, and height of the head can be adjusted by observing the tip of the head with a microscope while the rotating cylinder with the head moving device attached is assembled into the rotating magnetic head device (cylinder), and adjusting the variable resistor 58.59. At the azimuth angle of the head,
The tilt angle is adjusted, and then the height of the head is adjusted using a control circuit.

Of course, if there are many slip rings and brushes, it is possible to supply signals to the auxiliary coil from the fixed side via the slip rings and brushes. In this case, it is possible to control the azimuth angle and tilt angle while the head is rotating. This is particularly effective when used to improve performance in compatible playback. That is, by detecting the reproduction signal level and adjusting the azimuth angle or tilt angle so that the level is maximized, it is possible to improve the compatible reproduction characteristics. It is also of course possible to use the above adjustment as an initial adjustment by using a standard tape.

In the first embodiment described above, an example of adjusting the azimuth angle was described, and in the second embodiment, an example of adjusting the azimuth angle and the tilt angle was described, but it is also possible to adjust only the tilt angle. is obvious from the above explanation.

In the above embodiments, a direct current is applied to the auxiliary coil and no alternating current signal is applied. Therefore, this auxiliary coil can be used as a detection coil for detecting the movement of the head, and this detection coil can be used to perform feedback damping of the movement of the head. Examples will be described below. FIG. 7 shows a circuit block diagram in this case. Auxiliary coils 11 to 14 form a magnetic gap 8
It is well known that when moving at a certain speed within 0, an electromotive force (back electromotive force) proportional to the speed is generated. Since the drive coil 10 and the auxiliary coils 11 to 14 move as a unit, the auxiliary coils 11 to 14 can be used as detection coils, and the electromotive force thereof can be used as a signal for controlling the drive coil 10, for example, damping control. . The auxiliary coils 11 and 14 are wound in the same direction, and the auxiliary coils 12 and 13 are also wound in the same direction. Therefore, opposite powers in the same direction are generated in the auxiliary coils 11 and 14.

In FIG. 7, the voltage of the power supply 55 is determined by the variable resistor 6 as described above.
3, the azimuth angle is adjusted to be appropriate and supplied to the auxiliary coils 11 to 14 via the brush 53f, slip ring 54f, brush 53d, and slip ring 54d. A signal is taken out from between the auxiliary coils 14 and 12, and is taken out to the fixed side through the slip ring 54e and the brush 53e. The DC component of this signal is cut off by a capacitor 64 and the signal is input to an amplifier 62 .

As can be seen from the figure, the amplifier 62 has auxiliary coils 11 and 1.
The electromotive force generated in step 4 will be input.

Reference numeral 65 denotes a control signal generation circuit which generates a signal (triangular waveform at the time of search) for giving a desired operation to the head.

A difference signal between the outputs of the control signal generation circuit 65 and the amplifier 62 is supplied to the drive amplifier 61, and the drive coil 10 is driven by the drive amplifier 61.

As mentioned above, since the electromotive force generated in the auxiliary coils 11, 14 is proportional to the speed of movement thereof, the circuit shown in FIG. 7 can provide a damping effect to the movement of the drive coil 10. In the head moving device as shown in Fig. 1,
It has extremely low mechanical damping and extremely sharp resonance characteristics.

This deteriorates the characteristics of the device. Therefore, damping is an important issue, and this embodiment makes it possible to perform effective damping.

In the above embodiments, the auxiliary coil is a rectangularly wound coil bonded to the bobbin, but the shape of the auxiliary coil is not limited to this. An example is shown in FIG.

As shown in FIG. 8, the auxiliary coil 13' is wound diagonally with respect to the bobbin so that the front side of the bobbin is located at a low position and the opposite side (opposite side) is located at a high position. The auxiliary coil 11' is wound diagonally so that the front side of the bobbin is located at a high position and the opposite side is located at a low position. In other words, these auxiliary coils intersect on both the left and right sides of the bobbin in FIG.

Both auxiliary coils are located at a low level within the magnetic gap. This is the same as the previous embodiment.

The current flowing through each coil is in the opposite direction in the auxiliary coils 11' and 13', as shown by the arrows. The forces generated by these currents and their effects are the same as those in the above embodiment, so their explanation will be omitted.

An auxiliary coil 12' and an auxiliary coil 14' are wound on the lower part of the bobbin 15 in exactly the same manner. These coils are located in the magnetic gap at their elevated positions and their action is exactly the same as that of the auxiliary coils 11' and 13'.

Next, an example in which an auxiliary magnetic pole is provided instead of an auxiliary coil will be described. This embodiment will be explained based on FIGS. 9 and 10.

FIG. 9 is a view showing a cross section including the central axis and head of the head moving device, and FIG. 10 is a view of the outer yoke viewed from above.

As shown in Figure 9, there is a protrusion 9 on a part of the outer yoke.
1, 92, 93, and 94 are provided, and adjustment coils 81, 82, 83, and 84 are wound around these portions, respectively. As shown in FIG. 10, these protrusions have a constant width and are located at opposing positions 180 degrees apart, and windings of adjustment coils 81 and 83 are applied to these portions in the direction shown in the figure.

The direction of the magnetic field generated by energizing this winding is determined by the ninth
Auxiliary coils 105 and 106 are arranged at positions where these magnetic fields intersect, as indicated by arrows 101, 102, 103, and 104 in the figure. These auxiliary coils, like the drive coil 10, are wound around the outer periphery of the pobbin 15 in a cylindrical shape.

As is clear from FIG. 9, arrows 101-104 are all in the same direction. Therefore, the directions in which the magnetic flux crosses the auxiliary coils are opposite in the auxiliary coils 105 and 106.

Accordingly, the winding directions of the auxiliary coils 105 and 106 are reversed. The purpose of doing this is to cancel the influence of the main magnetic field generated by the permanent magnet with these two coils.

In FIG. 9, if the direction of the part of the magnetic field created by the adjustment coils 81, 84 that crosses the auxiliary coils 105, 106 is the same direction as the direction of the magnetic field created by the permanent magnet, then the adjustment coil 82
．． The directions of the portions of the magnetic field created by 83 that cross the auxiliary coils 105 and 106 are opposite directions. In other words, the auxiliary coil 105,
106, the force generated by the magnetic field generated by the current in the adjustment coils 81 to 84 is applied to the adjustment coils 81, 8.
The forces generated at portions 2 and 83 and 84 have the same magnitude and opposite directions. That is, as in the previous embodiments, a moment is generated to rotate the bobbin 15, and in the case of FIG. 9, it acts in a direction that changes the tilt angle of the head. If these adjustment coils 81 to 84, starting point 9
By rotating coils 1 to 94 by 90'' from the position shown in FIG. 9, these coils can be used for adjusting the azimuth of the head.

These adjustments can be achieved by adjusting the currents supplied to the auxiliary coils 105, 106 or by adjusting the currents supplied to the adjustment coils 81-84. Also, instead of winding the adjustment coils 81-84 around the projections 91-94, magnets magnetized to generate the magnetic fields shown by arrows 101-104 may be inserted into these parts. In this case, adjustment is made by the current supplied to the auxiliary coils 105, 106. In this case, these auxiliary coils 105 and 106 can be used as detection coils for detecting movement of the bobbin 15, just as in the example shown in FIG.

Although the example in which one head is moved by one head moving device has been described above, it is obvious that the same applies to the case where two heads are fixed to the tip of the leaf spring 8. Of course, if there are two heads, the azimuth angle and tilt angle of these heads cannot be adjusted separately, but errors in these angles are mainly due to the posture of the leaf springs, and these are Adjustment of the tilt angle and azimuth angle according to the present invention is useful since they are common to all heads. Furthermore, in the circuits shown in FIGS. 6 and 7, the current direction flowing through the auxiliary coil is unidirectional.

This is for the purpose of simplifying the explanation, and of course, the azimuth angle and tilt angle can be adjusted in both positive and negative directions by allowing current to flow in both directions.

Still another embodiment of the present invention will be described in FIG. 11. The difference between this embodiment and the embodiment shown in FIG.
15 and the magnetic gap 116 are provided separately from the magnetic gap in which the drive coil is arranged. These magnetic gaps are cylindrical gaps, in which portions of the auxiliary coils 11 to 14 are located. These magnetic gaps 115, 116 and the auxiliary coil 11 wound in a square shape
14 are the same as those shown in FIG. 1, and their functions are also the same. In this embodiment, this magnetic gap 11
5. Ring-shaped auxiliary magnet 1 to generate a magnetic field at 116
11 and 112 are arranged at the positions shown in the figure. These auxiliary magnets are radially magnetized and close to the magnetic gap 115.
, 116 to generate a --like magnetic field in the gap length direction.

By supplying current in the direction shown in FIG. 4 to the auxiliary coils 11 to 14, a force is exerted to tilt the bobbin and change the tilt angle or effective azimuth angle of the magnetic head 1. This is clear from the previous description.

〔Effect of the invention〕

According to the present invention, the attitude of a movably supported magnetic head can be easily adjusted using a simple device to improve signal recording and reproducing performance, and a power source for this purpose can be used.
It is also possible to obtain a head moving device with a simple configuration, low cost, and high performance for devices such as signal supply.

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of the head moving device of the present invention.
FIG. 2 is a diagram showing its appearance; FIG. 3 is a diagram showing the coil bobbin assembly; and FIG. 4 is a diagram showing the coil bobbin assembly with a leaf spring attached. FIG. 5 is a diagram showing a state in which a leaf spring is attached to a coil bobbin assembly according to another embodiment of the present invention, and FIG. 6 is a diagram showing a coil 1 distance movement circuit thereof. FIG. 7 is a circuit block diagram of another embodiment of the present invention. FIG. 8 is a diagram showing another embodiment of the auxiliary coil of the present invention. FIG. 9 is a diagram showing a head moving device of still another embodiment of the present invention. 10 is a partial view seen from above, and FIG. 11 is a sectional view of a head moving device according to still another embodiment of the present invention. 1... Magnetic head, 2, 3... Permanent magnet, 8, 9.
...Plate spring,]O...Driving coil, 11, 12, 13
．． 14...Auxiliary coil, 11', 12', 13'
, 14'... Auxiliary coil, 11', 12''... Auxiliary coil. 15... Bobbin, 41.42, 43.44... Auxiliary coil, 53 a, 53 b, 53 c-brush, 54a. 54b, 54c... Slip ring, 55... Power supply, 57... Preamplifier, 58.59... Variable resistor,
40...Magnetic circuit, 80.80'...Magnetic gap, 81°82.83,84...Adjustment coil, 91,9
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Claims (1)

[Claims] 1. A drive coil (1
0), and a magnetic circuit member (4) having a magnetic gap (80, 80') formed concentrically with the central axis of the drive coil (10) and containing at least the drive coil (10) therein.
0), and a spring member (8,
9), which is formed by winding a conductor, is connected and fixed to the drive coil (10), is disposed at a position offset from the drive coil (10) in the direction of its central axis, and is integrated with the drive coil (10); Air-core auxiliary coils (11, 12, 1) that move and displace
3, 14, 41, 42, 43, 44, 11', 12',
13', 14', 11'', 12'', 105, 106), and a magnetic head connected and fixed to the drive coil (10) and arranged at a radius position larger than the outer diameter of the magnetic circuit member (40). (1), a first control power supply unit (400) for supplying control current to the drive coil (10), and the auxiliary coil (11, 12, 13, 14, 41, 42).
, 43, 44, 11', 12', 13', 14', 11
a second control power supply unit (500) for supplying a control current to the magnetic head moving device (500). 2. The magnetic circuit member (40) is connected to the magnetic head (1).
2. The magnetic head moving device according to claim 1, wherein the magnetic head moving device is fixed to the outer peripheral edge of the rotating body with the outer radial direction. 3. The second control power supply unit (500) is composed of an adjustment circuit (58, 59) for adjusting the current value and a power supply (55), and the adjustment circuit (58, 59) is connected to the magnetic circuit. 3. The magnetic head moving device according to claim 2, wherein the magnetic head moving device is mounted on the same rotating body to which the member (40) is fixed. 4. The second control power supply unit (500) has its power supply (5
4. The magnetic head moving device according to claim 3, wherein the magnetic head (5) is also used as a power source for a preamplifier for amplifying the reproduced output of the magnetic head (1). 5. The above auxiliary coils (11, 12, 13, 14, 41,
42, 43, 44, 11', 12', 13', 14',
2. The magnetic head moving device according to claim 1, wherein portions of the wound conductors (11'', 12'') are located within the magnetic gaps (80, 80'). 6. The above auxiliary coils (11, 12, 13, 14, 41,
42, 43, 44, 11', 12', 13', 14')
Claim 1, wherein the drive coil (10) is composed of a plurality of coils arranged at symmetrical positions with respect to the central axis of the drive coil (10).
The magnetic head moving device described above. 7. The first control power supply unit (400) is configured to connect the auxiliary coils (11, 12, 13, 14, 41, 42, 43, 44
, 11', 12', 13', 14', 11'', 12'',
2. The magnetic head moving device according to claim 1, further comprising power feeding means for detecting a back electromotive force generated in the magnetic head (105, 106) and controlling the current to the drive coil (10) based on the detected back electromotive force. 8. The magnetic circuit member (40) is connected to the drive coil (1
0) and the above auxiliary coils (11, 12, 13, 14, 4
1, 42, 43, 44, 11', 12', 13', 14
2. The magnetic head moving device according to claim 1, wherein the magnetic head moving device has a structure including one magnetic cap including the magnetic caps 11'', 11'', 12''). 9. The magnetic circuit member (40) has a structure in which adjusting coils (81, 82, 83, 84) for increasing or decreasing the magnetic field strength of the magnetic cap (80, 80') are fixed. 1. The magnetic head moving device according to 1. 10. The magnetic head moving device according to claim 9, wherein the drive coil (10) has a structure in which an upper or lower part in the direction of the central axis is also used as an auxiliary coil. 11, the above auxiliary coil (11, 12, 13, 14, 41
, 42, 43, 44, 11', 12', 13', 14'
, 11'', 12'', 105, 106) are arranged separately at both upper and lower parts in the direction of the central axis of the drive coil (10). 12. The magnetic head moving device according to claim 1, wherein the drive coil (10) has a cylindrical shape. 13. The magnetic circuit member (40) has the drive coil (
10) on the central axis of the permanent magnet (
2 and 3) and a center yoke (5) are fixed, and a cylindrical outer yoke (7) is fixed concentrically to the central axis on the outer radius side of the drive coil (10). Or the magnetic head moving device according to 12. 14. The magnetic head moving device according to claim 13, wherein the magnetic circuit member has a fixing means formed of a hole or a notch on the yoke (4, 6, 7). 15. The spring members (8, 9) are connected to the drive coil (1).
0), the magnetic gap (80, 8
2. The magnetic head moving device according to claim 1, wherein the magnetic head moving device is a flat spring disposed on both sides of the magnetic head.