JP2000048339A - Magnetic disk storage - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a connection place from being destroyed by providing a notched part at terminal parts of suspensions containing an area where the terminal part is connected to the FPC of a wiring pattern to enable to reduce residual stress at the place. SOLUTION: One or two suspensions 4 are fixed to one arm 5a and a wiring pattern 4a to be provided in the suspensions 4 is connected to an FPC 7 by using solders or the like at terminal parts 4b. The terminal parts 4b extended from the suspension 4 are formed by being bent at the right angle and terminal parts of one pair of suspensions 4 to be attached to the one arm 5a are arranged on the same flat surface. Two terminal parts 4b are arranged at positions shifted from the same flat surface and the connection place is prevented from being destroyed by reducing stress to be concentrated on the connection place while making the terminal parts 4b easily bendable with respect to forces generated twisting and shearing of the FPC 7 which is to be connected to the wiring pattern 4a of the suspensions 4 with a notched part 4c.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk storage device for magnetically recording / reproducing information, and more particularly, to a magnetic disk storage device which is disposed on a suspension supporting a magnetic head, and connected to the magnetic head at one end. The present invention relates to a wiring pattern connected to an FPC that leads to a circuit that electrically processes information at an end, and to an improvement in connection reliability by reducing residual stress at a connection point of the FPC.

[0002]

2. Description of the Related Art Conventionally, a wiring pattern and an FPC which are arranged on a suspension supporting a magnetic head, are connected to a magnetic head at one end, and are connected to an FPC which leads to a circuit for electrically processing information at the other end. Connection is disclosed in Japanese Unexamined Patent Publication No.
As shown in Japanese Patent No. 61161, terminals of a pair of suspensions attached to one arm are bent at right angles to be arranged on the same plane, and solder or the like is provided between the pair of terminals and the FPC. This was done by sandwiching the connection material.

[0003] The terminal portion is usually made of stainless steel and a wiring pattern integrally with the suspension, and has a property that it is less flexible than an FPC made of polyimide and copper foil.

[0004] The bending of the terminals is performed by press bending or rolling bending. However, due to variations in materials and manufacturing processes, a pair of terminals are arranged at positions deviated from the same plane. Following the terminal portion at the connection point, twisting and shearing occur between the terminals. FPC
Generates a force to return to a flat state due to torsion or shearing, and thus generates residual stress in the solder used for connection with the FPC and the terminal portion. If the residual stress is too large, the connection portion is easily broken due to stress concentrated on the connection portion between the wiring pattern and the FPC and the solder, so that the connection reliability is reduced.

In order to reduce the residual stress, it is necessary to reduce the deviation of a pair of terminal portions from the same plane. However, it is necessary to reduce the allowable variation in bending of the terminal portions. It is not easy to manufacture suspensions inexpensively below.

JP-A-7-262540, JP-A-7-262540
In JP-A-262541, the influence of processing variations of the pair of terminals is reduced by forming a pair of suspensions attached to one arm from an integral member connected by the terminals. In this known example, two magnetic heads are mounted on an integral suspension, so if one magnetic head is defective, the pair of magnetic heads and the suspension must be replaced with a good one. The cost is higher than when the head and suspension are replaced.

[0007]

SUMMARY OF THE INVENTION A first object of the present invention is to provide a circuit arranged on a suspension for supporting a magnetic head, connected at one end to the magnetic head, and electrically processing information at the other end. It is an object of the present invention to realize a highly reliable magnetic disk storage device in which the connection portion is hardly broken by reducing the residual stress at the connection portion between the FPC and the wiring pattern connected to the FPC.

A second object of the present invention is to provide an inexpensive suspension and magnetic disk storage device that supports a magnetic head and allows processing variations in terminal portions covering the connection points in a suspension having the wiring pattern. It is to realize.

[0009]

A magnetic head is supported at one end, a suspension fixed to an arm at an end opposite to the magnetic head, and disposed on the suspension and connected to the magnetic head at one end. A magnetic head supporting mechanism having a wiring pattern connected to an FPC which leads to a circuit for electrically processing information at an end opposite to a terminal of a suspension including a region of the wiring pattern connected to the FPC. By providing notches,
The rigidity of the terminal portion is reduced, the residual stress caused by the deformation of the FPC before and after the connection is reduced, and the connection portion is hardly broken.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view of a magnetic disk storage device using a magnetic head support mechanism according to a first embodiment of the present invention.
Main parts such as the magnetic disk 1 and the magnetic head 2 are covered with a base 3 and a cover omitted in FIG. One or more magnetic disks 1 are provided with a spindle motor (not shown in FIG. 1) on the base 3 so as to maintain a gap between the adjacent magnetic disks 1 and between the base 3 and the cover. Has been fixed through.

The magnetic head 2 is mounted on one end of a suspension 4 so as to face the magnetic disk 1. The suspension 4 has an arm 5a at the end opposite to the magnetic head 2.
The arm 5a is fixed to a carriage 5 formed integrally with or separately from the arm 5a at an end opposite to the suspension 4. The carriage 5 is attached to the base 3 via a structure rotatable about the axis B, and can be rotated by a voice coil motor (VCM) 6 installed on the side of the carriage 5 opposite to the arm 5a.

The magnetic disk 1 can be rotated by a spindle motor about an axis A perpendicular to the disk surface and passing through the center of the disk, and the magnetic head 2 can be rotated by the VCM 6 about an axis B parallel to the axis A. The magnetic head 2 can be positioned at a desired position on the disk 1.

On the suspension 4, there is provided a wiring pattern 4a which is connected to the magnetic head 2 at one end and to a flexible printed cable (FPC) 7 at the other end. The FPC 7 is on the opposite side of the wiring pattern 4a. The end is connected to a circuit for processing information electrically.

With the configuration described above, the magnetic disk 1
At the desired position, the information electrically processed by the circuit is converted into a magnetic field by the magnetic head 2 through the FPC 7 and the wiring pattern 4a, and is magnetically recorded on the recording medium arranged on the magnetic disk 1. Alternatively, the magnetic field in the vicinity of the recording medium is converted into a current or a voltage by the magnetic head 2 and is electrically processed by the circuit connected via the wiring pattern 4a and the FPC 7 so that the magnetic disk 1 Can be reproduced.

FIG. 2 is a perspective view of the magnetic head support mechanism shown in FIG. One or two suspensions 4 are fixed to one arm 5a, and the wiring pattern 4a provided on the suspension 4 is connected to the FPC 7 at the terminal portion 4b using solder or the like. In this embodiment, an inductive head is used as a recording head, and a recording / reproducing separation type magnetic head using a magnetoresistive (MR) head is used as a reproducing head. The pattern 4a and the FPC 7 are each composed of four thin conductors, but may be composed of fewer or more conductors depending on the configuration of the magnetic head 2 and the circuit used. The wiring pattern 4a and the FPC 7 are connected to each other by soldering or the like at the terminal portion 4b for each pair of corresponding conductors.

FIGS. 3 (a), 3 (b) and 3 (c) are schematic diagrams showing a connection process between the wiring pattern 4a and the FPC 7 shown in FIG. The terminal portion 4b that protrudes from the suspension 4
Are formed at right angles, and the terminal portions of a pair of suspensions 4 attached to one arm 5a are arranged on the same plane. By inserting a connection material such as solder between the conductor pattern 4a of the terminal portion and the corresponding conductor of the FPC 7, and applying a load and heat to these portions for a proper time so that they are connected with sufficient strength. , The conductor pattern 4a and the FPC 7 are connected.

The bending of the terminal portion 4b is performed by press bending or rolling bending the suspension 4 made of a material such as stainless steel. Due to variations in materials and manufacturing processes, the bending position w and the angle θ have individual differences between different suspensions 4. When two suspensions 4 are attached to one arm 5a, two
Terminal portions 4b are arranged at positions shifted from the same plane,
The FPCs 7 connected to the wiring patterns 4a of the suspensions 4 follow the positions and angles of the terminal portions 4b at the respective connection points, so that twisting and shearing occur between the two terminal portions 4b.

F made of polyimide film, copper foil, etc.
Since the PC 7 generates a force to return to a flat state against torsion or shearing, residual stress is generated in the solder used for connection with the FPC 7 and the terminal portion 4b. If the residual stress is too large, the connection portion is likely to be broken due to stress concentrated on the connection portion between the wiring pattern 4a and the conductor of the FPC 7 and the solder, so that the connection reliability is reduced.

In the first embodiment of the present invention, one arm 5a is provided.
Terminals 4b of a pair of suspensions 4 attached to the vehicle
The notch 4c is provided on the side adjacent to the FPC 7 so that the terminal portion 4b is easily deflected by the force of the FPC 7 which is torsion or shearing to return to the flat state, and the stress concentrated on the connection portion is reduced. This makes it difficult to break the connection.

As a result of the examination in this embodiment, the thickness of the suspension 4 is 25 μm, the difference between the bending positions w between the two suspensions 4 is 60 μm, the difference between the angles θ is 10 °, and the depth of the notch 4 c is Assuming that the length of the terminal is 1/4,
It has been confirmed by analysis using the finite element method that the maximum value of the residual stress in the case where the notch 4c is present can be reduced to about two thirds as compared with the case where the notch 4c does not exist.

By providing the notch 4c in the terminal portion 4b, the wiring pattern 4a on the suspension 4 and the FPC
7 can reduce the residual stress in the connection of the FPC 7 and realize a highly reliable magnetic disk storage device in which the connection portion between the wiring pattern 4a and the FPC 7 is hardly broken by a load such as operation / stop of the magnetic disk device and a temperature. Becomes possible.

Further, even if sufficient strength of the connecting portion can be obtained without the notch 4c, the effect of reducing the residual stress can be obtained by providing the notch 4c.
It is possible to achieve a sufficient strength even if the individual difference of the bending position w and the angle θ is further increased. Therefore,
Since the allowable dimensional tolerances of the bending position w and the angle θ of the terminal portion 4b can be increased, the suspension can be easily manufactured and an inexpensive suspension can be obtained, so that an inexpensive magnetic disk storage device can be realized.

FIGS. 4A and 4B are perspective views showing a magnetic head support mechanism according to a second embodiment of the present invention. FIG.
Although the FPC 7 is omitted in FIGS.
The connection between C7 and the wiring pattern 4a and the configuration of the magnetic disk storage device are the same as in the first embodiment. In the case of the present embodiment, since the wiring pattern 4a is composed of four thin conductors, FP
The number of connection points with C7 is four per suspension 4, and three notches 4c are provided between the four connection points on the terminal portion 4b. Depending on the type and circuit configuration of the magnetic head 2, the number of conductors and notches 4c may be greater or less than in this embodiment.

Also in this case, the terminal portion 4b is easily deflected by the force of the FPC 7 which is subjected to torsion or shearing to return to a flat state, so that the residual stress at the connection portion is reduced and the connection portion is hardly broken. Thus, the same effect as in the first embodiment can be obtained.

Even when the first embodiment and the second embodiment are used in combination, the effects described in the first embodiment can be obtained.

FIGS. 5A and 5B are partially enlarged views of a terminal portion of a magnetic head supporting mechanism according to a third embodiment of the present invention. The configuration of other parts is the same as that of the first embodiment. As shown in the EE 'cross section, the area surrounded by the broken line of the terminal 4b on the back side of the wiring pattern 4a is removed by etching or the like to form the notch 4c, so that the terminal 4b is subjected to torsion or shearing. Since the FPC 7 is easily bent against the force of returning to the flat state, the same effect as in the first embodiment can be obtained.

The third embodiment can also be used in combination with the first and second embodiments.

[0029]

A magnetic head is supported at one end, and a suspension is fixed to an arm at an end opposite to the magnetic head. The suspension is disposed on the suspension and connected to the magnetic head at one end. In a magnetic head support mechanism having a wiring pattern connected to an FPC which leads to a circuit for electrically processing information at an end, a notch is provided in a terminal portion of a suspension covering a region of the wiring pattern connected to the FPC. Thereby, the rigidity of the terminal portion is reduced, the residual stress generated due to the deformation of the FPC before and after the connection is reduced, and the connection portion is hardly broken,
A highly reliable magnetic disk storage device can be realized.

Further, even when sufficient strength of the connection portion can be obtained without the notch, since the effect of reducing the residual stress can be obtained by providing the notch, individual differences in the bending position w and the angle θ of the terminal portion 4b can be obtained. It is possible to achieve a sufficient strength even if is further increased. Therefore, the terminal 4
Since the allowable dimensional tolerance of the bending position w and the angle θ of b can be increased, the manufacture of the suspension becomes easy, and an inexpensive suspension can be obtained, so that an inexpensive magnetic disk storage device can be realized.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a magnetic disk storage device using a magnetic head support mechanism according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing a magnetic head support mechanism according to the first embodiment of the present invention.

FIGS. 3A, 3B, and 3C are perspective views schematically illustrating a connection process between a wiring pattern disposed on a suspension and an FPC (and a section taken along line C′-C in FIG. 3A); (D sectional view of FIG. 3A).

FIGS. 4A and 4B are a perspective view showing a magnetic head support mechanism according to a second embodiment of the present invention and a sectional view taken along the line D in FIG. 4A.

FIGS. 5A and 5B are a partially enlarged sectional view of a terminal portion of a magnetic head supporting mechanism according to a third embodiment of the present invention and a sectional view taken along line EE of FIG. 5A.

[Explanation of symbols]

1: magnetic disk, 2: magnetic head, 3: base,
4 Suspension, 4a Wiring pattern, 4b Terminal part, 4c Notch, 5 Carriage, 5a Arm, 6 Voice coil motor (VCM), 7 F
PC.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masaaki Matsumoto 2880 Kozu, Odawara City, Kanagawa Prefecture Within Hitachi, Ltd. Storage Systems Division (72) Inventor Shuichi Sugawara 2880 Kozu, Kozu, Odawara City, Kanagawa Prefecture Hitachi, Ltd. Within the Storage System Division (72) Inventor Yoshinori Takeuchi 2880 Kozu, Kodawara-shi, Kanagawa Prefecture Within Hitachi Storage Systems Division, Ltd. (72) Inventor Tetsuo Maskawa 2880 Kozu, Kozu, Odawara-shi, Kanagawa Storage System Division, Hitachi, Ltd. F-term (reference) 5D042 NA01 TA02 TA05

Claims (1)

[Claims] A suspension that supports a magnetic head at one end and is fixed to an arm at an end opposite to the magnetic head;
A magnetic head support mechanism having a wiring pattern disposed on a suspension and connected to a magnetic head at one end and connected to an FPC at an end opposite to the magnetic head to a circuit for electrically processing information. A notch is provided in a terminal portion of a suspension covering a region connected to the FPC.