JPH073508Y2 - Floating magnetic head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a floating magnetic head used in a magnetic disk device or the like.

(Prior Art) In recent years, a floating magnetic head has been widely used, which is incorporated in a magnetic disk device or the like and floats a certain distance from the surface of the disk by air pressure generated by the rotation of the magnetic disk of the device.

FIG. 3 is a configuration diagram showing an example of a conventional floating magnetic head. FIG. 3 (A) is an enlarged perspective view, FIG. 3 (B) is an enlarged top view of essential parts in a magnetic disk device assembled state, and FIG. (C) is a side view of the same figure (B).

As shown in the figure, the conventional floating magnetic head 11 is composed of a magnetic head 2, a leaf spring 3, a pressing plate 4, and the like.

The lower surface of the tip portion 3e of the spring portion 3d of the leaf spring 3 formed by pressing a thin stainless plate is used for recording / reproducing information on / from a magnetic disk when incorporated in a magnetic disk device as described later. The magnetic head 2 is fixed to the upper surface of the magnetic head 2 with an epoxy resin adhesive. The lower surface of the substantially square mounting portion 3c on the other end side of the leaf spring 3 from the tip portion 3e is formed by pressing a metal plate having a thickness larger than that of the leaf spring 3. 3c
It is fixed to the upper surface of the pressing plate 4 having a substantially square shape having the same shape as. The fixing of the mounting portion 3c and the pressing plate 4 is such that the end portion and both side portions of the mounting portion 3c are aligned with the pressing plate 4,
Further, the hole 3b formed in the substantially central portion of the mounting portion 3c and the hole 4b formed in the substantially central portion of the pressing plate 4 are aligned,
This is performed by spot welding from the side of the mounting portion 3c. The position of the spot-welded portion 5b to which the spot-welding is applied is located along the four sides of the holding plate 4
Between the outer circumference of the hole and the holes 3b and 4b at substantially equal intervals.

The floating magnetic head 11 of the conventional example described above is used by being incorporated in the magnetic disk device as described above.

FIG. 2 is a perspective view of essential parts showing a schematic configuration of an example of a magnetic disk device incorporating a floating magnetic head according to an embodiment of the present invention and a conventional example.

As shown in the figure, the magnetic disk device 20 incorporating the above-mentioned conventional floating magnetic head 11 is
Besides 11, a magnetic disk 6, a spindle motor 7, a voice coil motor 8 and the like are included.

This magnetic disk 6 is an aluminum disc having a magnetic recording layer made of a magnetic material formed on its upper surface, and its center hole is fixed to the drive shaft 7a of this spindle motor 7, and, for example, at a constant rotation of 3,600 rpm. It is driven to rotate.

The mounting portion 3c of the floating magnetic head 11 and the pressing plate 4 are formed on the lower surface of the support portion 8a of the voice coil motor 8 by the holes 3b.
By tightening the screw 9 into the tapped hole 8b formed in the supporting portion 8a through 4 and 4b, the mounting portion 3c is pressed and fixed to the supporting portion 8a.

When the magnetic disk 6 is stopped, the magnetic head 2 is in contact with the upper surface of the magnetic disk 6 by the spring force of the spring portion 3d of the leaf spring 3 with a pressing force of, for example, about 10 gf. Further, when the magnetic disk 6 is in the steady rotation, the magnetic head 2 is
Due to the air pressure generated by the rotation of the disk 6,
For example, information is recorded / reproduced on / from the magnetic recording layer of the recording track of the disk 6 by being levitated by about 0.4 μm from the upper surface. At this time, the rotary shaft of the voice coil motor 8
Due to the rotational movement around 8c, this magnetic head 2
The position of the magnetic disk 6 is controlled at a predetermined position from the outer circumference to the inner circumference.

(Problems to be Solved by the Invention) In the conventional floating magnetic head 11 having the above-described configuration and the magnetic disk device 20 in which the floating magnetic head 11 is incorporated, the above-mentioned magnetic head 2 by the voice coil motor 8 is used. When the servo sampling frequency for position control is equal to or higher than the fundamental resonance frequency of the floating magnetic head 11, the resonance phenomenon of the floating magnetic head 11 occurs due to the vibration caused by the servo operation, and as a result, the magnetic head 2 described above is generated. The floating amount of the magnetic disk 6 from the upper surface fluctuates, the magnetic head 2 deviates from the recording track, and accurate tracing cannot be performed. Furthermore, in order to improve the performance of the magnetic disk device 20 and shorten the access time of the magnetic head 2, it is necessary to increase the moving speed of the magnetic head 2.
To this end, the servo sampling frequency must be increased, and this resonance phenomenon is more likely to occur. On the other hand, the floating magnetic head 11 is
However, as described above, it is difficult to increase the fundamental resonance frequency because it is configured to float during recording and reproduction. As described above, the above-mentioned conventional floating magnetic head 11 has a problem that its fundamental resonance frequency is low.

The present invention has been made in view of the above points, and it is an object of the present invention to provide a floating magnetic head having a high fundamental resonance frequency in order to make the above resonance phenomenon less likely to occur.

(Means for Solving the Problems) A floating magnetic head of the present invention is formed by a leaf spring, an information recording / reproducing magnetic head fixed to the tip side of the leaf spring, and the other end side of the leaf spring. Also, when the magnetic disk device is installed, the mounting part whose front surface side is pressed against the supporting part of this device by screwing, caulking, etc. and the mounting part that has approximately the same shape as this mounting part and is fixed by spot welding to the back surface of this mounting part Further, in a floating magnetic head having a metal plate pressing plate thicker than the plate spring, the mounting part and the pressing plate are formed on a protruding part protruding from the tip of the supporting part when the magnetic disk device is incorporated. The spot welding portion is provided.

(Embodiment) In the floating magnetic head of the present invention, the spot welding is added to the protruding portion of the mounting portion and the pressing plate from the tip of the supporting portion when incorporated in the above-mentioned magnetic disk device. Therefore, the fundamental resonance frequency described above is increased.

1A and 1B are configuration diagrams showing an embodiment of a floating magnetic head of the present invention. FIG. 1A is an enlarged perspective view, and FIG. 1B is an enlarged top view of essential parts in a magnetic disk device assembled state. The same figure (C) is a side view of the same figure (B). As shown in the figure,
The floating magnetic head 1 according to one embodiment of the present invention is different from the above-described conventional floating magnetic head 11 in that the above-mentioned protruding portion 3a and
Since the spot welded portion 5a is added to 4a, the same parts as those in the conventional example are designated by the same reference numerals, and the description thereof will be omitted.

Generally, the floating magnetic heads 1 and 11 are designed, manufactured, and sold by a specialized magnetic head manufacturer, and the manufacturer of the magnetic disk device often purchases from the magnetic head manufacturer. In the floating magnetic heads 1 and 11 manufactured by the magnetic head manufacturers, the length dimension l ₁ of the attaching portion 3c of the spring portion 3d of the leaf spring 3 and the pressing plate 4 in the longitudinal direction varies depending on each manufacturer. In this magnetic disk device manufacturer, the length dimension l ₂ of the overlapping portion of the mounting portion 3c and the pressing plate 4 up to the tip of the supporting portion 8a of the voice coil motor 8 on the spring portion 3d side is set. , It is usually designed to be as short or short as possible. The tip of the supporting portion 8a is attached to the mounting portion 3c and the pressing plate 4.
This is because there is a possibility that the operation of this spring portion 3d may be hindered if it exceeds the end portion (when l ₂ > l ₁ ).

Therefore, when the floating magnetic heads 1 and 11 are incorporated in the magnetic disk device, the protruding portions 3a and 4a are the portions where the mounting portion 3c and the pressing plate 4 protrude from the tip of the support portion 8a. Usually occurs.

As shown in FIG. 1, the floating magnetic head 1 according to the embodiment of the present invention has the above-mentioned spot welding portion 5b and the above-mentioned protruding portions 3a and 4a. The part 5a is formed. The positions of the spot welding portions 5a are, for example, three locations, that is, the central portion and both end portions of the protruding portions 3a and 4a. Actually, the length dimension l ₂ of the above-mentioned overlapping portion is assumed, and therefore, this protruding portion is
Assuming the dimensions of 3a and 4a, the position of this spot welding portion 5a is determined by the mounting portion 3c and the spring portion of the pressing plate 4.
It is set near the end on the 3d side.

Therefore, in the above-described head 1, as compared with the above-described conventional head 11, in the case of the conventional head 11, the positions of the attachment portion 3c and the spot welding portion 5b of the pressing plate 4 are the same as the outer circumference of the pressing plate 4. While it is approximately the midpoint between holes 3b and 4b,
In the case of this head 1, since the position of the spot welded portion 5a is near the end portion of the attachment portion 3c and the pressing plate 4 on the spring portion 3d side, the effective spring length is shortened. This is because, in the case of the conventional head 11, when the magnetic head 2 floats as described above, the mounting portion 3c is separated from the holding plate 4 by a small amount near the end of the holding plate 4 on the side of the spring portion 3d. On the other hand, in the case of this head 1, this separation is suppressed by the spot welding portion 5a.

The leaf spring 3 has a narrow tip end that takes a relatively high frequency response, and a wide root end that takes a relatively low frequency response. Since it has a component, the influence of this difference in the root part becomes large.

Further, as in the above-mentioned conventional example and the embodiment of the present invention, a spring provided with ribs as shown in FIGS. 1 (A) and 3 (A) from the central portion to the tip portion of the leaf spring 3. In the case of a normal magnetic head employing the portion 3d, the contribution of the root portion where the rib is not provided is high in the operation of the leaf spring 3, and therefore the head 1 of the embodiment of the present invention and the conventional one. In the example head 11, the difference in the effective spring length with respect to the above-mentioned low frequency component becomes large.

The floating magnetic head 1 described above is incorporated and used in the magnetic disk device 10 shown in FIG.

As shown in the figure, the magnetic disk device 10 in which the floating magnetic head 1 is incorporated is different from the above-mentioned magnetic disk device 20 in that the floating magnetic head 11 is replaced by the floating magnetic head 1.
However, the description of the same parts will be omitted.

In the magnetic disk device 10, the floating magnetic head 1 has the spot welding portions 5a formed on the protruding portions 3a and 4a as described above, and is different from the head 11 of the conventional example described above. As described above, since the effective spring length is shortened and the basic resonance frequency is high, the resonance phenomenon described above is less likely to occur due to the vibration caused by the servo operation for the position control of the magnetic head 2 by the voice coil motor 8. Therefore, the reliability of the trace of the recording track by the magnetic head 2 is improved. Since the spot welding portion 5a can be formed simultaneously with the spot welding portion 5b, the floating magnetic head 1 can be constructed without increasing the cost as compared with the above-described conventional floating magnetic head 11.

Further, in the floating magnetic head 1, if the flash of the spot welding portion 5b of the mounting portion 3c is large, the adhesion of the voice coil motor 8 to the supporting portion 8a is deteriorated, and the basic resonance frequency is lowered. The height of the flash from the surface of the mounting portion 3c is small, for example, 5 μm or less due to adjustment of welding conditions during the spot welding.

In the above-described embodiment of the present invention, the protruding portion 3a is
While the example in which the spot welding portions 5a of 4a and 4a are formed at three locations has been described, in order to avoid the resonance phenomenon described above, when changing the basic resonance frequency, the protruding portions 3a and
Within the range of 4a, it is possible to adjust the position and the number of the spot welding parts 5a.

Further, in the above-mentioned one embodiment, the example in which the recording / reproducing is performed on one side of the magnetic disk 6 has been described. The present invention can be similarly applied to the case where the floating magnetic heads are stacked on the drive shaft 7a and corresponding to the surface of each disk 6.

(Effect of the Invention) In the floating magnetic head of the present invention having the above configuration, the basic resonance frequency is high and the resonance phenomenon is hard to occur when the magnetic disk device is incorporated. Is improved. Moreover, since the structure can be configured without increasing the cost, the function-to-cost ratio is improved.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of a floating magnetic head of the present invention, and FIG. 2 is a schematic configuration of an example of a magnetic disk device incorporating the floating magnetic head of the embodiment of the present invention and a conventional example. FIG. 3 is a perspective view of a main part shown in FIG. 3, and FIG. 3 is a configuration diagram showing an example of a conventional floating magnetic head. 1,11 ...... Floating magnetic head, 2 ...... Magnetic head, 3 ...... Leaf springs, 3a, 4a ...... Overhanging part, 3c ...... Mounting part, 3d ...... Spring part, 3e ...... Tip part, 4 ...... Holding plate, 5a, 5b ...
... Welding part, 6 ... Magnetic disk, 8 ... Voice coil motor, 8a ... Support part, 8b ... Tap hole, 9 ... Screw, 1
0,20 ... Magnetic disk unit.

Claims (1)

[Scope of utility model registration request] 1. A leaf spring, an information recording / reproducing magnetic head fixed to the tip side of the leaf spring, and a coupling and fixing means formed at the other end of the leaf spring when the magnetic disk device is assembled. A mounting portion whose front surface side is pressed against the supporting portion of the device; and a pressing plate made of a metal plate having a shape substantially the same as that of the mounting portion, which is fixed to the back surface of the mounting portion by spot welding and is thicker than the leaf spring. A floating magnetic head having a spot welding portion formed on a protruding portion from which the mounting portion and the pressing plate protrude from the tip of the supporting portion when the magnetic disk device is incorporated. .