JPH06176335A - Magnetic head assembly and magnetic disk device - Google Patents

Abstract

PURPOSE:To prevent the influence of disturbance noise on the microreproduced signal of a lead wire for connection and to enhance the quality of the reproduced signal by providing a magnetic head supporting member with a shielding member for shielding the lead wire for connection. CONSTITUTION:A magnetic head 24 is supported on the magnetic head supporting member 25 and the lead wire 22 for connection to the head 24 is disposed at the magnetic head supporting member 25. The magnetic head supporting member 25 of the magnetic head assembly is provided with the shielding member 4 for shielding the lead wire 22 for connection. The shielding member 4 for shielding the lead wire 22 for connection of the magnetic head 24 is provided at the magnetic head supporting member 25, by which the lead wire 22 is electrically shielded and the microreproduced signal of the lead wire 22 is no longer subjected to the influence of the disturbance noise. The supply of the reproduced signal with the high accuracy to a circuit is possible.

Description

Detailed Description of the Invention

(Table of Contents) Industrial Application Field of the Prior Art (FIG. 10) Problem to be Solved by the Invention (FIG. 11) Means for Solving the Problem (FIG. 1) Action Example (a) First Implementation Description of Example (FIGS. 2 to 5) (b) Description of Second Embodiment (FIGS. 6 to 7) (c) Description of Third Embodiment (FIGS. 8 to 9) (d) Other Implementations Explanation of example Effect of invention

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head assembly and a magnetic disk device for recording / reproducing on / from a magnetic disk by a magnetic head.

A magnetic disk device is a storage device in which a magnetic head is positioned on a rotating magnetic disk by an actuator so as to perform track positioning, and the magnetic head reads / writes data from / to the track of the magnetic disk.

This magnetic disk device is widely used as an external storage device, and in accordance with the recent demand for downsizing of computer systems, downsizing and large capacity are required, and the size of the magnetic disk is 5. It is moving from 25 inches to 3.5 inches and 1.8 inches.

In order to miniaturize and increase the capacity of this magnetic disk device, high density mounting is being attempted, and along with this, the reproduction signal from the magnetic medium to the magnetic head is also miniaturized.
The influence of noise due to external disturbances cannot be ignored, and countermeasures are needed.

[0006]

2. Description of the Related Art FIG. 10 is an explanatory diagram of a conventional technique. As shown in FIG. 10A, the magnetic disk device has a rotating magnetic disk 10 and a magnetic head assembly 2 having a magnetic head core 21 at its tip, and the magnetic head core 21 of the magnetic head assembly 2 is attached to the magnetic disk 10. Is sought in a direction intersecting with the track and positioned on a desired track, and the read / write of the data of the track is performed by the magnetic head core 21.

The seek operation of the magnetic head assembly 2 employs a swing arm system which enables downsizing of the apparatus, and the seek operation is performed by rotating about the axis. This magnetic head assembly 2 is
Suspension 20 with magnetic head core 21 at the tip
As shown in FIG. 10B, the suspension 20 has a leaf spring shape, supports the magnetic head core 21 at its tip, and applies a spring force to the magnetic head core 21.

In this magnetic head assembly, the magnetic head core 21 is adhered to the tip of the suspension 20 with an adhesive, and then the lead wire 22 in the tube 23 is connected (bonded) to the magnetic head core 21, coated, and then the tube 23. Was hooked on the hook on the suspension 20 and arranged (lead homing).

The tube 23 is made of an insulating material such as Teflon for the purpose of mechanically protecting the lead wire 22.

[0010]

FIG. 11 is a diagram for explaining the problems of the prior art. In order to reduce the size and increase the capacity of the magnetic disk device, firstly, it is necessary to increase the recording density for increasing the capacity. In this case, the signal frequency becomes high and the reproduction signal becomes minute. To do.

Second, in order to reduce the size, as shown in FIG. 11, it is necessary to reduce the distance d between the magnetic disks 10 to be stacked, which is, for example, about 3 mm, and a pair of magnetic heads arranged between them. The interval between 21 is also small and is about 1 mm.

As described above, when the size and the capacity are increased, the following problems occur in the prior art. When the reproduction signal becomes minute, the reproduction signal is transmitted to the lead wire 22.
It becomes weak against a little noise from, and the quality of the reproduced signal deteriorates.

When the distance between the magnetic heads 21 becomes small,
The influence of noise appears between the magnetic heads 21. For example, when a write current is applied to another magnetic head while one magnetic head is reproducing a servo signal, high frequency noise due to the write current causes a servo signal to be generated. It mixes with the lead wire to be transmitted, disturbs a minute servo signal, and makes servo control unstable.

Since the reproduced signal becomes minute, the reproduced signal is affected by the reflection noise from the head IC composed of an amplifier or the like. Therefore, it is an object of the present invention to provide a magnetic head assembly capable of preventing the influence of the disturbance noise (electromagnetic wave or the like) generated in the device on the reproduction signal of the lead wire.

The present invention also provides a magnetic disk device capable of performing stable read / write operation by preventing the influence of disturbance noise (electromagnetic waves, etc.) generated in the device on the reproduction signal of the read wire. To aim.

[0016]

FIG. 1 shows the principle of the present invention. According to claim 1 of the present invention, the magnetic head supporting member 25 is provided.
In the magnetic head assembly in which the magnetic head 24 is supported and the connecting lead wire 22 for connecting to the magnetic head 24 is arranged on the magnetic head supporting member 25, the connecting lead wire 22 is connected to the magnetic head supporting member 25. Is provided with a shield member 4 for shielding.

According to claim 2 of the present invention, in claim 1,
The shield member 4 is a conductive tube 40 for protecting the connecting lead wire 22. According to a third aspect of the present invention, in the first aspect, the damping member 41 provided on the magnetic head supporting member 25 is used as the shield member 4, and the damping member 41 is provided between the magnetic head supporting member 25 and the damping member 41. In addition, the lead wire 22 is provided.

A fourth aspect of the present invention is based on the first aspect.
The lead wire 22 is provided on an insulating base 440, and a shield layer 442 is provided via an insulating layer 441 to shield the lead wire 22.

A fifth aspect of the present invention is characterized in that in the first, second, third or fourth aspect, the magnetic head 24 is a head for reproducing a servo signal. A sixth aspect of the present invention provides a rotating magnetic disk 10 and a magnetic head 2.
4, a magnetic head support member 25 for supporting the magnetic head 4 and a moving means 30 for moving the magnetic head support member 25 in a direction intersecting the tracks of the magnetic disk 10, and a magnetic disk for recording and reproducing by the magnetic head 24. In the apparatus, the magnetic head 2 is attached to the magnetic head supporting member 25.
4 is provided with a shield member 4 for shielding the connecting lead wire 22.

According to a seventh aspect of the present invention, in the sixth aspect,
The shield member 4 is a conductive tube 40 for protecting the connecting lead wire 22. According to an eighth aspect of the present invention, in the sixth aspect, the damping member 41 provided on the magnetic head supporting member 25 is used as the shield member 4, and the damping member 41 is provided between the magnetic head supporting member 25 and the damping member 41. In addition, the lead wire 22 is provided.

A ninth aspect of the present invention is based on the sixth aspect.
The lead wire 22 is provided on an insulating base 440, and a shield layer 442 is provided via an insulating layer 441 to shield the lead wire 22.

A tenth aspect of the present invention is characterized in that, in the sixth, seventh, eighth or ninth aspect, the magnetic head 24 is a head for reproducing a servo signal.

[0023]

In the first and sixth aspects of the present invention, the magnetic head 24
Since the shield member 4 for shielding the connection lead wire 22 is provided on the magnetic head support member 25, the lead wire 22 can be electrically shielded by the shield member 4, and a minute reproduction signal of the lead wire causes disturbance noise. Is not affected, and the read / write characteristics are not deteriorated even if the size and the capacity are increased.

According to claims 2 and 7 of the present invention, the lead wire 2
Since the tube for protecting 2 is shielded by the conductive tube 40, it can be easily realized by making the conventional tube for mechanical protection conductive.

According to the third and eighth aspects of the present invention, since the damping material 41 for damping the magnetic head supporting member 25 can be used as the shield member 4, it can be easily realized. According to claims 4 and 9 of the present invention, since the shield layer 442 is provided and shielded on the lead wire 22 provided on the insulating base via the insulating layer 441, a flat cable can be used, and the shield operation and magnetic The placement on the head support member 25 is also easy.

According to the fifth and tenth aspects of the present invention, since the shield is applied to the head for reproducing the servo signal, that is, the servo head for the servo surface servo, and the data head for the data surface servo, a small servo signal is applied. It is possible to prevent the servo operation from becoming unstable due to noise being mixed in.

[0027]

【Example】

(a) Description of First Embodiment FIG. 2 is a configuration diagram of a magnetic disk device according to an embodiment of the present invention, FIG. 3 is a sectional view of an actuator according to an embodiment of the present invention, and FIG. 4 is an actuator according to an embodiment of the present invention. And FIG. 5 is a configuration diagram of a first embodiment of the present invention.

The magnetic disk device shown in FIG. 2 is a magnetic disk device for carrying out magnetic recording by floating a head on a 1.8-inch magnetic disk. A 1.8-inch magnetic disk 10 that rotates about a spindle shaft 12 and a magnetic circuit 13 are provided on a base 11 of the apparatus, and an actuator 3 is attached so as to be rotatable about a rotation shaft 31. ing.

As shown in FIGS. 2, 3 and 4, the actuator 3 is provided with a coil 32 at the rear portion,
The coil 32 is located between the magnetic circuits 13. Nine arms 30 are formed in the front part of the actuator 3, and each arm 30 is provided with a suspension 25 having a magnetic head 24 at its tip, and eight layers of magnetic disks (not shown) are provided.

As shown in FIG. 4, the suspension 25 is provided with the lead wire 22 of the magnetic head 24, and a flat cable (FPC) provided on the side surface of the arm 30.
26, and is connected to a head IC 27 including an amplifier and the like provided near the rotary shaft 31 of the arm 30 by a flat cable 26.

The actuator 3 constitutes a linear actuator by the coil 32 and the magnetic circuit 13, and when a current is passed through the coil 32, the actuator 3 rotates about the rotary shaft 31 to move the magnetic head 24 to the magnetic disk 10. Seek drive is performed in the direction intersecting with the track (radial direction).

In FIG. 5, reference numeral 25 denotes a suspension, which is made of a spring metal such as stainless steel and is attached to the arm 30. Reference numeral 24 denotes a magnetic head having a size within about 1 mm in length and width, and the suspension. 25 is attached to the tip of 25 with an adhesive, 22 is a lead wire, copper wire is coated with polyurethane to be insulated from the outside, 40 is a conductive tube, Teflon, carbon, etc. The conductive filler is dispersed to have conductivity, and the lead wire 22 is provided inside.
Is to be inserted.

Numeral 26 is a flat cable, and the arm 3
A head IC, which is attached to the side surface of 0, includes a read amplifier and the like, is provided on the arm 30, and is connected to the magnetic head 22 via the flat cable 26 and the lead wire 22.

Although the suspension 25 is attached to the lower part of the arm 30, the suspension 25 and the like are also attached to the upper part. In this embodiment, one end of the lead wire 22 in the conductive tube 40 is connected to the magnetic head 24 by bonding or the like, and then the conductive tube 40 is hooked on the hook of the suspension 25 to be fixedly arranged on the suspension 25 to make the conductive property. The other end of the lead wire 22 in the tube 40 is connected to the terminal of the flat cable 26 provided on the arm 30 by bonding or the like.

In this way, the tube 4 for protecting the lead wire 22 connecting the magnetic head 24 and the flat cable 26.
Since 0 is composed of a conductive tube, disturbance noise can be prevented from being mixed into the lead wire 22 due to the shielding effect.

Therefore, it is possible to prevent the read signal (including the servo signal) of the magnetic head 24 from mixing the electromagnetic noise caused by the write signal from the adjacent magnetic head and also the mixing of the reflection noise from the head IC.

The conductive tube 40 has a function of mechanically protecting the lead wire 22 in addition to the shield effect, and can be realized by simply changing the tube without increasing the number of assembly work steps.

The conductive tube 40 in which carbon is dispersed in Teflon is also flexible and follows the flexure and vibration of the suspension 25 and flexes, so that no extra force is applied to the lead wire 22. There are advantages.

The conductive tube is preferably flexible, and even if it is made of metal, the suspension 2
Any material having flexibility similar to that of 5 may be used. Further, in this embodiment, it is better to shield the lead wire 22 at the connecting portion of the magnetic head 24 at the tip portion of the suspension 25, but it is not shielded. This portion is for connection work with the magnetic head 24. Above, it is easier to work if the lead wire 22 is exposed, and
When it is covered with 0, the tube 40 exerts an extra force on the lead wire 22 due to the vibration of the suspension 25,
This is because the lead wire 22 is easily detached.

(B) Description of the Second Embodiment FIG. 6 is a block diagram of the second embodiment of the present invention, and FIG. 7 is a sectional view of the essential portions of the second embodiment of the present invention.

The structure of the magnetic disk drive of the embodiment of FIGS. 6 and 7 is the same as that of FIGS. 2 to 4, and only the magnetic head assembly is shown. 6 and 7, the same components as those shown in FIGS. 2 to 5 are designated by the same symbols, 41 is a damping material, and the suspension 25
It is provided above and absorbs the vibration of the suspension 25.

As shown in the sectional view of FIG. 7, the damping material 41 has a viscoelastic material 42 (for example, product name "VEM" manufactured by 3M Co., Ltd.) and a restraint plate 43 made of stainless steel or the like. And vibrating the suspension 25 vibrations.
2 converts into heat and absorbs it, and restrains the viscoelastic body 42 from being deformed or biased by the restraint plate 43.

The lead wire 22 is positioned between the viscoelastic material 42 and the suspension 25, and the restraint plate 43 provides a shield effect. Since the viscoelastic material 42 has adhesiveness, the lead wire 22 is arranged at the bottom of the suspension 25, and the viscoelastic material 42 is attached onto the lead wire 22,
Further, the lead wire 22 is fixed by sticking the restraint plate 43 onto the viscoelastic material 42.

After that, one end of the lead wire 22 is connected to the magnetic head 24, and the other end is connected to the flat cable 26 on the side surface of the arm 30. In this way, suspension 2
The lead wire can be shielded by using the vibration damping material 41 for suppressing the vibration of No. 5, and it can be realized without any additional parts.

As the restraint plate 43 of the damping material 41, one having a high shielding effect is desirable, and it is more preferable to use permalloy, copper or the like having a high shielding effect instead of the above-mentioned stainless steel.

(C) Description of Third Embodiment FIG. 8 is a configuration diagram of an embodiment of the present invention, and FIG. 9 is a configuration diagram of essential parts of a third embodiment of the present invention.

In the embodiment of FIGS. 8 and 9, the structure of the magnetic disk device is the same as that of FIGS.
Only the magnetic head assembly is shown. In FIGS. 8 and 9, the same components as those shown in FIGS. 2 to 5 are designated by the same symbols, and 44 is a flat cable, which electrically connects the magnetic head 24 and the head IC 27. It is for.

The flat cable 44 has a conductor pattern 22a extending from the tip of the suspension 25 to the head IC 27, and a shield layer 442. Figure 9
In the flat cable 44, the signal line (conductor pattern) 22a is provided on the insulating base 440.
An insulating adhesive layer 441 is provided thereon, a metal shield layer 442 such as copper is provided on the adhesive layer 441, and the protective cover layer 4 is provided.
43 is provided and configured.

The flat cable 44 is attached to the bottom of the suspension 25 and to the side surface of the arm 30 to connect the terminal portion at the tip of the flat cable 44 and the magnetic head 24 with the wire 22b. The terminal portion at the rear end and the head IC 27 are wire-connected.

In this way, the lead wire, which is the conductor pattern 22a, is shielded by the shield layer 442, so that the minute signal reproduced by the magnetic head 24 can be protected from noise and sent to the circuit in a stable state. .

Further, in this example, the conductor pattern up to the head IC 27 is also shielded, so that noise is further enhanced. Moreover, in this example, the flat cable 26 on the side surface of the arm 30 is integrated so that the number of parts can be reduced.

(D) Description of Other Embodiments In addition to the embodiments described above, the present invention can be modified as follows. Although the description has been given for the flying type magnetic head, it can be applied to the contact type magnetic head.

Although a plurality of magnetic disks has been described in the magnetic disk device, one magnetic disk may be used. The shielded magnetic head assembly of the above-described embodiment can be used only for servo heads in the case of servo surface servos, and for all data heads in the case of data surface servos. It may be used for the head.

The present invention has been described above with reference to the embodiments.
Various modifications are possible within the scope of the invention, and these modifications are not excluded from the scope of the invention.

[0055]

As described above, according to the present invention,
It has the following effects. Since the shield member 4 for shielding the connecting lead wire 22 of the magnetic head 24 is provided on the magnetic head supporting member 25, the lead wire 22 can be electrically shielded by the shield member 4, and a minute reproduction signal of the lead wire can be obtained. Can be supplied to the circuit with high quality without being affected by disturbance noise.

Therefore, it is possible to provide a stable and high-quality magnetic disk device without deteriorating the read / write characteristics even if the size and the capacity are increased.

[Brief description of drawings]

FIG. 1 is a principle diagram of the present invention.

FIG. 2 is a configuration diagram of a magnetic disk device according to an embodiment of the present invention.

FIG. 3 is a sectional view of an actuator according to an embodiment of the present invention.

FIG. 4 is a front view of an actuator according to an embodiment of the present invention.

FIG. 5 is a configuration diagram of a first embodiment of the present invention.

FIG. 6 is a configuration diagram of a second embodiment of the present invention.

FIG. 7 is a configuration diagram of a main part of a second embodiment of the present invention.

FIG. 8 is a configuration diagram of a third embodiment of the present invention.

FIG. 9 is a configuration diagram of a main part of a third embodiment of the present invention.

FIG. 10 is an explanatory diagram of a conventional technique.

FIG. 11 is a diagram illustrating a problem of the conventional technique.

[Explanation of symbols]

 2 magnetic head assembly 3 actuator 4 shield member 10 magnetic disk 13 magnetic circuit 20, 25 suspension (magnetic head support member) 21, 24 magnetic head 22 lead wire 26 flat cable 27 head IC 30 arm 40 conductive tube 41 damping material 42 Viscoelastic material 43 Restraint plate 44 Flat cable 442 Shield layer

Claims (10)

[Claims] 1. A magnetic head (24) is supported by a magnetic head support member (25), and a lead wire (22) for connecting to the magnetic head (24) is arranged on the magnetic head support member (25). In the magnetic head assembly, the connecting lead wire (2) is attached to the magnetic head supporting member (25).
A magnetic head assembly comprising a shield member (4) for shielding 2). 2. The conductive tube (4) for protecting the connecting lead wire (22) by the shield member (4).
0) The magnetic head assembly of claim 1, wherein 3. A damping material (41) provided on the magnetic head supporting member (25) is used as the shield member (4), and the magnetic head supporting member (25) and the damping material (4) are used.
The magnetic head assembly according to claim 1, wherein the lead wire (22) is provided between the magnetic head assembly and the magnetic head assembly. 4. The insulating wire (4) for connecting the lead wire (22).
40. The magnetic head assembly according to claim 1, wherein the magnetic head assembly is shielded by being provided on the insulating layer (441) and provided with a shield layer (442) on the insulating layer (441). 5. A magnetic head assembly according to claim 1, 2 or 3 or 4, wherein said magnetic head (24) is a head for reproducing a servo signal. 6. A magnetic head support member (25) for supporting a rotating magnetic disk (10) and a magnetic head (24).
And a moving means (30) for moving the magnetic head support member (25) in a direction intersecting the track of the magnetic disk (10), and the magnetic head (24) performs recording and reproduction. In the magnetic head support member (25), the magnetic head (2
4) A magnetic disk device comprising a shield member (4) for shielding a lead wire (22) for connection with 4). 7. The conductive tube (4) for protecting the connecting lead wire (22) by the shield member (4).
7. The magnetic disk drive according to claim 6, which is 0). 8. A damping material (41) provided on the magnetic head supporting member (25) is used as the shield member (4), and the magnetic head supporting member (25) and the damping material (4) are used.
7. The magnetic disk drive according to claim 6, wherein the lead wire (22) is provided between the magnetic disk drive and the lead wire (1). 9. The lead wire (22) is connected to an insulating base (4).
40) The magnetic disk device according to claim 6, wherein the shield layer (442) is provided on the insulating layer (441) and is shielded. 10. The magnetic disk device according to claim 6, wherein the magnetic head (24) is a head for reproducing a servo signal.