JPH0778879B2 - Head transfer device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a head transfer device for transferring a head for recording, reproducing or erasing information on an information track formed on a recording medium.

2. Description of the Related Art Conventionally, a flexible printed circuit board is generally often used as a means for supplying an electric signal to a movable unit including an objective lens as an element that focuses light on an arbitrary information track of a recording medium. .

For example, in Japanese Patent Laid-Open No. 63-13140, an optical head transfer device for supplying an electric signal to a movable unit including an objective lens as an element for condensing light on an information track of a recording medium using a flexible printed circuit board is disclosed. Proposed. The first conventional technique will be described with reference to FIG.

Further, in Japanese Patent Application Laid-Open No. 61-42741, there is provided a structure for guiding the movement of a movable unit including an objective lens as an element for focusing on an information track of a recording medium without using a guide shaft having a bearing loss and a bearing. An optical head transfer device has been proposed. The second conventional technique will be described with reference to FIG.

First, the first conventional technique will be described with reference to FIG.

6 (a) and 6 (b) are a cross-sectional view and a bottom view of the conventional optical head transfer device (first conventional technique) taken along the line I-I.

In FIG. 6, the X direction is the direction orthogonal to the information track of the recording medium (called the tracking direction), the Z direction is the direction perpendicular to the recording medium (called the focus direction), the Y direction is the X direction, The direction is perpendicular to both the Z direction and the tangential direction of the information track of the recording medium.

The frame 101 is provided in a housing (not shown) of the optical recording / reproducing apparatus, and is attached to the housing via four leg members (not shown). The frame 101 is made of aluminum or its alloy.

A pair of columnar steel support rails 105 and 106 extending in the arrow X direction and the opposite direction thereof and spaced apart in the arrow Y direction and the opposite direction are fixed to the frame 101 at both ends thereof. . A longitudinal pickup body 107 as a holding member extending in the arrow Y direction and the opposite direction is positioned so as to be sandwiched by the support rails 105 and 106, and is movably supported by the support rails.

Further, the frame 101 is provided with a pair of longitudinal magnetic circuits 120 each including a longitudinal magnet 116 and longitudinal yokes 117 and 118 that extend along the moving direction of the pickup body 107 (the direction of the arrow X and the opposite direction) and are attached to each other. It is fixed. A pair of drive coils 121 is attached to the pickup body 107 such that the central axis of the coil is parallel to the moving direction of the pickup body. The magnetic circuit 120 described above forms a magnetic flux interlinking with the drive coil, and together with the drive coil constitutes a linear motor as a moving force applying means for applying a moving force to the moving optical system including the pickup body 107. .

The coil 122 is wound around the outer periphery of each of the drive coils 121 described above such that the coil center axis is concentric with the coil center axis of the drive coil, and the magnetic circuit 120 forms a speed detecting means.

A holding member 125 is attached to the rear end of the frame 101. The holding member 125 has a laser diode 127 as an emitting element, a collimator lens 128 for collimating the irradiation light emitted from the laser diode, a converging lens 129, and reflected light from the recording surface of the disc 115 finally. The light receiving element 130 for receiving and obtaining the information signal, the irradiation pattern of the parallel light emitted through the collimator lens 128 is shaped and guided to the objective lens described later, and the reflected light from the disk recording surface is guided to the light receiving element 130. A compound prism 131 and an astigmatism element 132 that gives astigmatism to the reflected light for the purpose of detecting the focus error of the light beam emitted toward the recording surface of the disc are attached.

Further, the pickup body 107 has an objective lens 15 for focusing parallel light that has passed through a total reflection prism (not shown) on the recording surface of the disk 115 as a fine spot light.
8 and a holder 159 and a supporting member (not shown) for movably supporting the objective lens in two directions, that is, the optical axis direction (arrow F direction) and the direction perpendicular thereto (arrow T direction). The support mechanism, a magnetic circuit including the magnet 162 and the yoke 163, and a coil (not shown) wound around the holder 159 so that the magnetic flux from the magnetic circuit interlinks with each other. And a drive source that gives the moving force of the. The drive source and the objective lens support mechanism described above are collectively referred to as a servo drive mechanism.

Further, a flexible printed circuit board 165 for supplying a drive current to the servo drive mechanism mounted on the pickup body 107 is provided. The flexible printed circuit board is bent in a U shape in its thickness direction, and is arranged in the movement trajectory of the pickup body 107 and its thickness direction is parallel to the recording surface of the disk 115. There is.

A turntable 166 is provided in front of the pick-up body 107 to carry the disk 115 and rotate.

As described above, according to the first conventional technique, the objective lens 158 and the holding member (pickup body 107) holding the servo driving mechanism thereof are bent to follow the movement and supply the driving current to the servo driving mechanism. A flexible printed circuit board 165 for bending is arranged in a U-shape in the thickness direction so as to be in the movement locus of the holding member and so that the thickness direction is parallel to the recording surface of the recording medium. ing. By arranging the flexible printed circuit board in this way, the load exerted by the flexible printed circuit board on the movement of the holding member can be kept relatively small, and information can be reproduced or recorded smoothly. It is a thing.

Next, the second conventional technique will be described with reference to FIG.

FIG. 7 is a perspective view of a conventional head transfer device (second prior art).

In FIG. 7, the X direction is the direction orthogonal to the information track of the recording medium (called the tracking direction), the Z direction is the direction perpendicular to the recording medium (called the focus direction), the Y direction is the X direction, The direction is perpendicular to both the Z direction and the tangential direction of the information track of the recording medium.

Reference numeral 231 is a reflecting mirror adjusted so that the optical axis of the objective lens 207 is reflected along the optical path C of the optical disc 201 in the X direction, and is fixed to the carriage 233. An automatic focus control mechanism 208 is provided on the upper surface of the carriage 233, and the objective lens 207 is finely adjusted in the optical axis direction to focus. The carriage 233 having such a structure is directly connected to the movable shaft 234 integrally formed with the moving coil 235 of the voice coil motor 206, and the movable shaft 234 is connected to the voice coil via the leaf spring 236 having flexibility in the X direction. Spacer screws 238 are used at the fixed portion 237 of the motor 206 to support the motor 206 at two front and rear positions. A magnetic circuit 239 can position the carriage 233 on the medium surface of the optical disc 201 in the X direction by supplying a control current to the moving coil 235. Even if the carriage 233 moves, since the moving direction matches the optical path C, the optical axis does not move, and the reflecting mirror 232 can guide the light in a desired direction.

Further, the structure and operation of the optical system housed in the fixed portion of the optical recording / reproducing apparatus main body is that the laser light emitted from the laser diode 212 of the light source becomes a parallel light beam by the collimator lens 213, and is circular by the perfect circle correction prism 214. The light beam is adjusted into a light beam, passes through the polarization beam splitter 215 and the λ / 4 plate 216 (λ is the wavelength of the laser beam), is condensed into a light beam spot by the objective lens 207, and is irradiated onto the track of the optical disc 201.

Further, the reflected light from the optical disc 201 travels backward in the incident optical path, is reflected at a right angle by the polarization beam splitter 215, and is received by the photodetector 219 via the cylindrical lens 217 and the condenser lens 218. ing.

In addition to this, the optical system further houses a detection circuit 220 such as a focus detection system, a track position detection system, and a signal detection system.

As described above, according to the second conventional technique, the movable portion of the optical head is guided by the leaf spring 236 having flexibility in the X direction without using the guide shaft and the bearing having the bearing loss, and the reliability of the apparatus is improved. It is possible to improve the sex.

However, in the first prior art, it is necessary to fix one of both ends of the flexible printed circuit board to the movable unit and the other to the fixed portion of the optical recording / reproducing apparatus. It took time to work, the number of parts was large, and the mass of the movable unit was heavy. That is, although the above-mentioned conventional technique does not describe a method for fixing a flexible printed circuit board, if it is fixed by adhesion, for example, assembly work will take time. Further, when fixing with screws, it is usually stopped together with the reinforcing plate, so in addition to the screws, in many cases, an additional reinforcing plate is required, resulting in an increase in the number of parts and a heavy weight of the movable part.

Further, in the first conventional technique, it is necessary to perform the work carefully so as not to leave a crease that may cause a wire break due to bending during the work, thus making the assembling work difficult.

In the second prior art, a voice coil motor
206 and automatic focus control mechanism 208 exist independently of each other,
If the autofocus control mechanism 208 is composed of the most general-purpose voice coil motor, the voice coil motor 20
6 and the automatic focus control mechanism 208 require separate magnetic circuits, which makes the head larger, which in turn results in a larger head transfer device equipped with this head.

Further, although there is no description regarding the supply of the electric signals of the voice coil motor 206 and the automatic focus control mechanism 208, the supply of the electric signals is performed by forming the flexible printed circuit board or the like into a substantially U shape as in the first prior art. Therefore, it has the same drawbacks as those of the first prior art, and further has a drawback that it takes a considerable space because the flexible printed circuit board or the like has a substantially U shape and is movable. Was.

In view of the above point, the object of the present invention is not only to perform the assembling work easily and in a short time, but not to increase the weight of the movable unit (the carriage and the movable portion of the head mounted on the carriage). In addition, the space is reduced and downsizing is possible, and the movable unit is moved in the direction orthogonal to the information track of the recording medium by using the magnetic circuit common to the voice coil motor that drives the objective lens in the direction perpendicular to the recording medium. Moreover, it is an object of the present invention to provide an optical head transport device having a simple and inexpensive structure with a small number of parts.

Means for Solving the Problems In order to achieve the above object, a head transfer device of the present invention is an objective lens that focuses a light beam on an information track of a recording medium, and a mover bobbin that houses the objective lens.
A carriage that movably supports the mover bobbin at least in a direction perpendicular to the recording medium; a focus coil that is provided on the mover bobbin and drives the objective lens in a direction perpendicular to the recording medium; Provided on at least one of the child bobbin or the carriage,
At least a tracking coil that drives the carriage in a direction orthogonal to the information track, a magnetic circuit that supplies a magnetic flux to the focus coil and the tracking coil to generate a driving force, and moves the carriage in a direction orthogonal to the information track. In the magnetic circuit, the yoke is provided on both sides of the carriage in the tangential direction of the information track, and the yoke is wider than the width of the carriage in the orthogonal direction of the information track. A magnet is provided on at least one of the yokes that is long, and the leaf spring unit includes a notch for penetrating the yoke, a first fixing portion for fixing the carriage, and a second fixing portion for fixing the magnetic circuit. Around the notch, and means for transmitting and receiving an electric signal to and from the carriage. It is obtained by the.

In the means for achieving the above object, by supplying an electric signal to the carriage through a leaf spring unit that supports the carriage movably in the direction orthogonal to the information track, the assembling work is simple and time-consuming. The number of parts can be reduced, the mass of the movable unit is not increased, the space is reduced, and the head transfer device can be downsized. Furthermore, a magnetic circuit that supplies a magnetic flux in common to both the focus coil that drives the objective lens in the direction perpendicular to the recording medium and the tracking coil that drives at least the carriage in the direction orthogonal to the information track of the recording medium to generate a driving force Further, the number of parts is small, and the structure is simple and inexpensive, and it is not necessary to mount a magnetic circuit for driving the objective lens on the carriage, so that the movable unit can be further reduced in weight.

Embodiment FIG. 1 to FIG. 5 show an embodiment of the present invention, FIG. 1 is an exploded perspective view, and FIGS. 2 (a) and 2 (b) are a top view and an AA ′ sectional view. 3 (a) and 3 (b) are a top view and a front view of a main part, FIG. 4 is a sectional view taken along the line BB ', and FIGS. 5 (a) and 5 (b) are a leaf spring and a flexible member. FIG. 4 is a front view of a single printed circuit board.

1 to 5, the X direction is a direction orthogonal to the information track of the recording medium (called a tracking direction), the Z direction is a direction perpendicular to the recording medium (called a focus direction), and the Y direction. Is a direction perpendicular to both the X direction and the Z direction, and is a tangential direction of the information track of the recording medium.

Hereinafter, this embodiment will be described with reference to FIGS. 1 to 5.

Reference numeral 1 is a recording medium, which is an optical disc having spiral or concentric information tracks. A disk motor 2 is a motor for mounting the recording medium 1 and rotating the same. Reference numeral 3 denotes a fixed optical unit in which a semiconductor laser serving as a light source, a detector for detecting reflected light from the recording medium 1, and an optical element such as a prism for collimating a light beam from the semiconductor laser into a fixed member are housed in a fixed member. is there.

Reference numeral 4 denotes an objective lens, which is an element, and is an element for condensing the light beam on the recording medium 1. 5 is a mover bobbin,
The objective lens 4 is housed on the side of the recording medium 1 in the Z direction, and two focus coils 5a for driving this in the Z direction and two tracking coils 5b for driving it in the X direction are wound. Reference numeral 6 denotes a balance weight, which is housed at a position opposite to the recording medium 1 in the Z direction of the mover bobbin 5, that is, a position facing the objective lens 4 in order to maintain the dynamic balance of the mover bobbin 5. Reference numeral 7 denotes a focus leaf spring unit as an objective lens supporting means, which includes a central cylindrical portion 7a and a peripheral portion 7b.
Is a spiral leaf-shaped focus leaf spring, a damping rubber that damps the resonance of this focus leaf spring, and an auxiliary spring that reinforces the peripheral portion 7b, and has a three-layer sandwich structure. A central cylindrical portion 7a is adhered and fixed to the outer peripheral portion of the cylindrical portion of the child bobbin 5 in which the objective lens 4 is housed. 7a is fixed by adhesion. Reference numeral 7c is a positioning hole for adhering and fixing the peripheral portion 7b to the carriage 8 to be described later, one is a round hole and the other is a long hole. Reference numeral 8 denotes a carriage, and peripheral portions 7b of two objective lens supporting means (focus leaf spring units) 7 are adhered and fixed on the surface on the recording medium 1 side in the Z direction and the surface on the opposite side. Reference numeral 8a is a positioning boss for adhering the peripheral portion 7b of the objective lens supporting means (focus leaf spring unit) 7. Further, 8b is a positioning boss for positioning a leaf spring unit 11 described later. Reference numeral 9 denotes a reflection mirror, which is a mirror for reflecting the light beam emitted from the fixed optical unit 3 in the X direction in the Z direction. Reference numeral 10 is a reflection mirror holder, and the reflection mirror 9 is adhesively fixed to the carriage 8. Note that 10a is the same as 8b
It is a positioning boss for positioning a leaf spring unit 11 described later. Reference numeral 11 denotes a leaf spring unit, which has a sandwich structure of a leaf spring 11A described later and a flexible printed circuit board 11B described later. The flexible printed circuit board 11B is oriented outward with respect to the carriage 8 and has a positioning hole 11a. And the positioning boss 8b of the carriage 8 or the positioning boss 10a of the reflection mirror holder 10 are used for positioning and adhesion, and the holes 11b and the screw holes 12a of the leaf spring holder 12 to be described later are screwed and fixed. The deformation of the deforming portion 11c supports the carriage 8 so as to be linearly movable in the X direction. 11A is a leaf spring made of stainless steel. Reference numeral 11B is a flexible printed circuit board which supplies a drive current to the two focus coils 5a and the two tracking coils 5b. Note that 11Ba is a copper foil pattern that supplies a drive current. 11Bb has two focus coils
5a and two tracking coils 5b are solder-plated portions that connect with a twisted wire (not shown). 11Bc is a drive circuit (not shown) of the optical recording / reproducing apparatus main body (not shown).
It is a solder plating part for connecting to. Reference numeral 12 denotes a leaf spring holder, which fixes the leaf spring unit 11 with a screw by a screw hole 12a and a hole 11b of the leaf spring unit 11. The hole 12
Reference numeral b is a hole for screwing and fixing to a back yoke 14 described later. 13 is a magnet, which is a back yoke 1 described later.
4, opposing yoke 15, side yoke A16, side yoke B17
Together with the magnetic circuit, the movable element bobbin 5 is driven in the Z direction by the electromagnetic force with the focus coil 5a, and the carriage 8 and the movable element bobbin 5 are driven in the X direction by the electromagnetic force with the tracking coil 5b. Therefore, the magnet 13
The magnetic circuit such as the above and the tracking coil 5b constitute a transfer means. Reference numeral 14 is a back yoke, which is made of electromagnetic soft iron and has a magnet 13 bonded and fixed thereto. In addition,
The leaf spring holder 12 is screwed and fixed by the screw hole 14a and the hole 12b of the leaf spring holder 12. 15 is an opposing yoke,
It is made of electromagnetic soft iron and is arranged at a position facing the magnet 15. Reference numeral 16 is a side yoke A, which is made of electromagnetic soft iron and fixes the back yoke 14 and the opposing yoke 15 at the tips. Reference numeral 16a is a hole for fixing the optical recording / reproducing apparatus main body (not shown) with screws. Reference numeral 16b denotes a fixed optical unit mounting portion, which has two holes for fixing the fixed optical unit 3, one of which serves as a set screw and a reference hole without backlash, and the other of which has a larger hole than the set screw.
It can be screwed and fixed in a form that allows tilt adjustment around the direction. Reference numeral 17 denotes a side yoke B, which is made of electromagnetic soft iron and fixes the back yoke 14 and the counter yoke 15 at their tips. Like 17a, 17a is a hole for screwing and fixing to a recording / reproducing apparatus main body (not shown).
Reference numeral 18 denotes a fixed optical unit support spring, which is an L-shaped leaf spring for connecting and fixing the side yoke A16 and the fixed optical unit 3. That is, the fixed optical unit 3 is fixed at two positions with a sufficient distance, that is, the side yoke A16, the fixed optical unit mounting portion 16b, and the fixed optical unit support spring 18, and has a stable fixing structure against vibration and impact. There is.

In addition, the focus coil 5a and the tracking coil 5b
The movable unit, which is moved by the driving force generated in, is roughly composed of two movable units. The first is a movable unit A, which is supported by an objective lens support means (focus leaf spring unit) 7 and is integrally configured by the objective lens A, a balance weight 6, a mover bobbin 5, a focus coil 5a, and a trunking coil 5b. It is a unit The second is a movable unit B, which is supported by a leaf spring unit 11 and includes a reflection mirror 9 and a carriage 8.
And the reflection mirror holder 10 is an integral unit.

In addition, in the movable unit A and the movable unit B, when the driving force is not generated in the tracking coil 5b,
As shown in FIG. 3, it is arranged at the center of the magnetic circuit in the X direction, that is, at the middle position of the recording medium 1.

The operation of the head transfer device of this embodiment constructed as described above will be described below.

First, when a drive current flows through the focus coil 5a, a drive force is generated in the Z direction by the electromagnetic action with the magnetic circuit in the focus coil 5a. At this time, since the spiral portion of the objective lens support means (focus leaf spring unit) 7 that supports the movable unit A with respect to the movable unit B is sufficiently soft in the Z direction, the spiral of the objective lens support means (focus leaf spring unit) 7 The movable unit A moves in the Z direction due to the deformation of the part.

On the other hand, when a driving current flows through the tracking coil 5b, a driving force is generated in the X direction by the electromagnetic action with the magnetic circuit in the tracking coil 5b. At this time, the rigidity of the spiral portion of the objective lens support means (focus leaf spring unit) 7 in the X direction and the masses of the movable unit A and the movable unit B supported by the objective lens support means (focus leaf spring unit) 7 are determined. The driving force generated in the tracking coil 5b up to the resonance frequency (around 1 kHz) in the X direction of the objective lens support means (focus leaf spring unit) 7 is applied to the movable unit B via the objective lens support means (focus leaf spring unit) 7. However, at a frequency higher than the resonance frequency, the objective lens supporting means (focus leaf spring unit) 7 is substantially equivalent to that, and the driving force generated in the tracking coil 5b is applied to the movable unit B. Not transmitted. That is, in the X direction, the movable unit changes at the boundary of the resonance frequency of the objective lens support means (focus leaf spring unit) 7 in the X direction, and this resonance frequency is referred to as split resonance. Therefore, both the movable unit A and the movable unit B vibrate up to the frequency of the split resonance, and only the movable unit A vibrates at the frequency after the split resonance.

Further, when the movable unit B is moved at a low frequency due to the split resonance, the movement of the leaf spring unit 11, which is the supporting member, is deformed in the form shown by the broken line and the alternate long and short dash line in FIG. That is, the movable unit B and the movable unit A can be linearly moved in the X direction. At this time, the driving force generated in the tracking coil 5b and the restoring force of the leaf spring unit 11 balance each other.

Therefore, when the information of any information track of the recording medium 1 is reproduced or erased, a driving current for generating a driving force corresponding to the restoring force of the leaf spring unit 11 at that time is DC-directed to the tracking coil 5b. All you have to do is add.

Further, by supplying an electric signal to the movable unit via the leaf spring unit 11 that movably supports the movable unit in the direction orthogonal to the information track, the assembly work can be performed easily and in a short time. It is possible not only to reduce the weight of the movable unit, but also to reduce the space and to downsize the head transfer device.

Further, by using a magnetic circuit common to a voice coil motor that drives an objective lens as an element in a direction perpendicular to the recording medium, a necessary movable unit of the head is moved in a direction orthogonal to an information track of the recording medium, and It is possible to provide a head transfer device having a small number of points and a simple and inexpensive structure.

In addition, by constructing the leaf spring unit by integrating the leaf spring and the flexible printed circuit board, it is possible to provide both movable support and electric signal supply to the movable unit with a very simple structure. ing.

In addition, in the present embodiment, the transfer device of the separation type optical head having the structure in which the head is separated into the fixed optical unit and the movable optical unit has been described, but the integrated optical head configured to transfer the entire optical head. Is also valid.

Further, in the present embodiment, as shown in FIG. 3, the deformed portions of the leaf spring unit 11 are provided at two locations on both sides of the movable unit B and the movable unit A in the Y direction, but for example, the movable unit A and the movable unit B are provided. The deformed portions may be provided at two locations on one side in the Y direction and one location on the other side.

As described above, according to the present invention, the assembly work can be performed by supplying the electric signal to the movable unit through the leaf spring unit that movably supports the movable unit in the direction orthogonal to the information track. To provide an optical head transfer device that can be performed easily and in a short time, the number of parts can be reduced, the mass of a movable unit is not increased, and the space can be further reduced and downsized. You can

Furthermore, the carriage and therefore the movable unit are moved in the direction orthogonal to the information tracks of the recording medium by using the magnetic circuit common to the voice coil motor that moves the objective lens in the direction perpendicular to the recording medium, and the number of parts is small and simple. Therefore, the movable unit can be further reduced in weight because there is no need to mount a magnetic circuit for driving the objective lens on the carriage.

Further, by providing the deformed portions of the leaf spring unit on both sides of the movable unit, the movable unit can be linearly moved, and the information track of the recording medium and the moving locus of the movable unit can be always orthogonal to each other.

These are the optical axis of the light beam emitted from the fixed optical unit and the movement of the movable unit in the transfer device of the separation type optical head in which the optical head is separated into the fixed optical unit and the movable optical unit as in this embodiment. It is particularly effective because the locus and the locus should match as closely as possible.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing an embodiment of the present invention, FIGS. 2 (a) and 2 (b) are top views and AA ′ sectional views, and FIGS. 3 (a) and 3 (b) are main parts. Top and front view of the fourth
The figure is a cross-sectional view taken along the line BB ', FIGS. 5 (a) and 5 (b) are front views of a leaf spring and a flexible printed circuit board separately, and FIGS. 6 (a) and 6 (b) are conventional optical heads. FIG. 7 is a sectional view and a bottom view of the transfer device, and FIG. 7 is a perspective view of a conventional optical head transfer device. 1 ... recording medium, 4 ... objective lens, 5 ... mover bobbin, 5a ... focus coil, 5b ... tracking coil, 7 ... objective lens support means (focus leaf spring unit), 8 ... carriage, 9 ... Reflective mirror, 11A ...
… Leaf spring, 11B …… Flexible printed circuit board (11 …… Leaf spring unit), 13, 14, 15, 16, 17 …… Magnetic circuit.

Claims (2)

[Claims] 1. An objective lens for focusing a light beam on an information track of a recording medium, a mover bobbin accommodating the objective lens, and a movable bobbin movably supported at least in a direction perpendicular to the recording medium. And a focus coil provided on the mover bobbin for driving the objective lens in a direction perpendicular to the recording medium, and provided on at least one of the mover bobbin and the carriage, and at least the carriage is provided with the information. A tracking coil that drives in the direction orthogonal to the track, a magnetic circuit that supplies a magnetic flux to the focus coil and the tracking coil to generate a driving force, and a leaf spring that movably supports the carriage in the direction orthogonal to the information track. A magnetic circuit is provided with a yoke of the carriage. The yoke is provided on both sides in the tangential direction of the information track, the yoke is longer than the width of the carriage in the orthogonal direction of the information track, and at least one yoke is provided with a magnet, and the leaf spring unit includes: A notch for penetrating the yoke, a first fixing part for fixing to the carriage, and a second fixing part for fixing to a magnetic circuit are provided around the notch, and means for sending and receiving an electric signal to and from the carriage are provided. A head transfer device. 2. A means for transmitting and receiving an electric signal to and from the carriage,
The head transfer device according to claim 1, wherein the head transfer device is made of a flexible printed board that is attached to a leaf spring in a thickness direction.