JPH06168573A - Magnetic recorder - Google Patents

Abstract

PURPOSE:To facilitate the wiring work by forming a projection capable of conducting with a conductive member with conductive material for filling a through hole formed on the base member of a suspension FPC and connecting it with the coil of a magnetic head electrically. CONSTITUTION:The suspension flexible printed circuit board(FPC) 25 is constituted of two layers of a base film 25-1 and the conductive member 25-2 on the transmission of an electric signal. Then, the through hole 25-4 is formed on the base film 25-1, and a conductive projection 31 capable of conducting with the conductive member 25-2 by the conductive material for filling the through hole 25-4 is connected directly and electrically with the coil pad 9 of a thin film magnetic head. By such a constitution, the wiring work of a head lead wire to the coil pad 9 of the magnetic head is facilitated, and a magnetic recorder having a magnetic head gimbals assembly easy for manufacture is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is mounted on a fixed magnetic disk device which is the mainstream of external storage devices for computers.
The present invention relates to a magnetic recording device equipped with a magnetic head gimbal assembly for transmitting information to and from a magnetic disk.

[0002]

2. Description of the Related Art The structures of a conventional magnetic disk device and magnetic head gimbal assembly will be described with reference to FIGS. A conventional magnetic head gimbal assembly guarantees a magnetic head 101, a floating slider 102 on which the magnetic head 101 is mounted, and a floating slider 102 that is adhered to the floating head so as to have freedom in pitching and rolling directions in a floating state of the floating slider. Floating slider for gimbal 103 1
Suspension 104 that suspends 02 via gimbal 103
And a magnetic head 101 and a recording / reproducing amplifier (R / WAMP) 112
It comprises a conductive wire 105 and a hollow tube 106 for transmitting an electric signal to and from, and a caulking mount 107 for mechanically connecting the magnetic head gimbal assembly and the drive arm. A conductive wire 105 for transmitting an electric signal between the magnetic head 101 and the R / W AMP 112 is a hollow tube 106 of two or three wire rods having a diameter of 0.2 to 0.3 mm.
Has been pierced. Hollow tube 106 has an inner diameter of 0.25 m
The suspension 104 is caulked and fixed to the suspension 104 by bending a tab of a caulking mount 107 formed on a flange portion with an outer diameter of m and an outer diameter of about 0.5 mm. Further, the conductive wire 105 is, for example, when the magnetic head to be mounted is a thin film magnetic head type, a head lead terminal patterned on the floating slider trading edge end face by photolithography technology, and pressure contact by ultrasonic bonding, etc. Combined by The magnetic head 101 and R / W AMP112 are R / W AMP112
R / formed on a flexible circuit board mounting
W AMP112 head signal line pad (RDX / R
DY) and the conductive wire 105 are electrically connected by soldering. The magnetic head gimbal assembly 118 is fixed to an oscillating or direct acting arm integrally formed with the voice coil motor by caulking or screwing. The arm 115 is driven by energizing the voice coil motor, the magnetic head 101 mounted on the magnetic head gimbal assembly moves on the surface of the magnetic disk and is positioned on a predetermined track, and information is recorded on the magnetic disk. Play.

[0003]

However, the magnetic head gimbal assembly constructed as described above has the following problems. 1) A conductive wire for transmitting between the magnetic head 101 and the R / W AMP 112 is applied to a head winding coil terminal pad formed by a photolithographic method on a trading edge end surface of a floating slider in the case of a thin film magnetic head. Bonding is done by sonic wire bonding. Coil terminal pad for wire bonding W1 = 0.4m
It is a minute pattern of m, L2 = 0.8 mm. For this reason, wire bonding is an operation within the field of view of the microscope, which requires the skill of the operator such as positioning of the bonding pattern and handling of the wire bonder.
There is a problem in terms of man-hours, and there is a problem that for automation, an expensive and precise automated production line such as an automatic bonding device having a highly precise positioning accuracy by an image processing function is required.

2) The wire-bonded conductive wire is cut into a predetermined length, inserted into a hollow tube, and further fixed to the flange portion or the central portion of the upper surface of the suspension 104 by forming and caulking (see FIG. 8). At this time, the conductive wire is twisted several times between the magnetic head 101 and the hollow tube so as to prevent the conductive wire from hanging down on the magnetic disk when the floating slider floats. When the radius of the service loop becomes large, the service loop hangs down due to its own weight and does not serve its initial purpose. At this time, a restoring force is applied to the floating slider due to the deformation of the service loop during forming, and the floating slider deteriorates the pitching posture and the rolling posture with respect to the reference plane of the suspension 104. This posture deterioration causes deterioration of the flying characteristics of the floating slider, and the magnetic head gimbal
When using the assembly, there is a problem that the loading characteristics of the floating slider are significantly deteriorated, which causes a crash phenomenon of the floating slider.

3) Further, the end opposite to the end connected to the magnetic head with the conductive wire cut into a predetermined length is R / W A
A soldering process is required for conduction with the MP112. Flexible printed circuit board for R / W AMP
Magnetic head signal (RDX / RD) formed on (FPC) 113
Y) Solder to the pad and magnetic head 101 and R / W AMP
Make electrical connection with 112. Normal R / W AMP FP
C113 is screwed and fixed to the shroud base of the fixed magnetic disk device, and a part of it is routed to the arm 115 for electrical connection with the magnetic head 101. RDX / RD
The Y pads are arranged on the side surface of the swing arm 115 or the linear motion arm and are formed by the number of windings of the magnetic head 101.
However, with the downsizing and thinning of the fixed magnetic disk device, the height and width of the side surface of the arm 115 tend to be narrowed, for example, the 3.5-inch fixed magnetic disk device 1
Inch height model has H = 10mm and W = 10mm, and RDX / RDY pad (including center tap pad) when 4 magnetic heads, gimbal assemblies are mounted.
The shape is very small with a width of 0.3 to 0.4 mm and a length of 0.8 to 1.0 mm. For this reason, the soldering work of the conductive wire to the RDX / RDY pad on the flexible printed circuit board (FPC) is a work within the field of view of the microscope, requires skill level, and the work man-hour is long and the ratio to the total man-hour is high. There is a problem in that it is a large work process that is difficult to automate.

4) In the fixed magnetic disk device, information recording is performed on tracks concentrically arranged on the magnetic disk at a pitch of about 10 μm. Truck is 10 ~
It is divided into about 100 sectors, and each sector is composed of an ID part related to recording of a track number, a head number, and a sector number, and a data part related to recording / reproducing of user data. Recording (WRITE), playback (READ), move (SEEK) to a specific sector from a host computer system
The fixed magnetic disk unit that received the command is a floating slider
The magnetic head 101 is moved to a target track, and the head switching signal of the R / W AMP 112 is changed to electrically select the magnetic head 101 corresponding to the target sector. When the target sector reaches below the selected head due to the rotation of the disk, the hard disk drive
The (HDD) controller executes data transmission between the magnetic disk and the buffer memory. Data recording and reproduction are executed by the above operation.

The movement of the floating slider 102 and the magnetic head 101 to the track to which the target sector belongs is performed by the current drive of the voice coil motor. Here, a vibration type voice coil motor (VCM) will be described as an example. FIG. 9 shows the configuration of a general vibration type voice coil motor. A carriage 119 in which a plurality of arms 115 to which the magnetic head gimbal assembly 118 is fixed by crimping or screwing is integrated has a through hole near the center. A pair of bearings have their inner rings fixed to a common shaft 122, and their outer rings fixed to the inner wall of the through hole while being preloaded with each other. The carriage 119 is rotatable about the shaft 122 as the center of rotation. The coil fixed to the end of the carriage arm 115 and the HDD
A magnetic circuit fixed inside is formed. The coil and the magnetic circuit are arranged so as to be orthogonal to the magnetic flux, and when a direct current is applied to the coil, the arm 115
Rotating torque is generated to drive the magnetic head gimbal assembly 118 fixed at the tip of the arm 115 by caulking or screwing, and enables high speed movement on the surface of the magnetic disk.

While moving to the target track, the magnetic head 101 reads servo information (track information) recorded continuously or intermittently on the magnetic disk, estimates the speed at each time point, and compares it with the command value to determine the voice coil. It moves by controlling the current supplied to the motor. At this time the magnetic head 101
The suspension 104 that supports the various types of vibration modes (twisting and bending) caused by the rotational torque generated in the coil makes the reading of the servo information unstable, and especially when the track density is increased, the seek of the magnetic head 101 is increased. There was a problem that errors were likely to occur. In order to solve this problem, a method of controlling the vibration of the suspension 104 by sandwiching an adhesive material having a damping effect on the suspension 104 with a braking plate has been devised, which causes a significant increase in price. It has new problems.

The present invention is intended to solve the above-mentioned several problems, and an object thereof is to provide a magnetic recording apparatus having a magnetic head gimbal assembly which is easy to manufacture.

[0010]

In order to achieve the above object, the present invention provides a gimbal suspension for suspending a floating slider having a magnetic head for recording / reproducing digital information, the magnetic head and a recording / reproducing amplifier. (R / W
A member configured by a flexible printed circuit board (FPC) having flexibility through transmission of an electric signal to and from the AMP, a conductive member related to the transmission of the electric signal by the FPC, and a fixed protection of the conductive member. And a through hole is formed in the base member, and conductive protrusions (bumps) capable of conducting electricity with the conductive member by a conductive material filling the through hole are formed. The magnetic head gimbal assembly is formed so that the coil forming the magnetic head and the conductive protrusions can be directly electrically coupled to each other.

[0011]

With the above-described structure, the present invention facilitates the wiring work of the head lead wire to the head pad, reduces the work requiring skill, and improves the defective rate at the time of assembly and reduces the number of steps. . Further, the present invention enables electrical connection between the R / W amplifier head input terminal and the magnetic head on the FPC, prevents pitching / rolling posture accuracy deterioration of the floating slider, and improves the flying characteristics of the floating slider. It is possible to stabilize the levitation posture.

Further, when the non-contact start / stop method (for example, the ramp loading method) is adopted, the loading characteristics of the floating slider can be remarkably improved by improving the pitching / rolling posture accuracy. Further in the present invention,
Since the work of soldering the conductive wire to the RDX / RDY pad, which requires skill in the carriage arm assembly assembling process, is eliminated, the number of assembling steps can be significantly reduced.

Further, the positioning of the head pullout FPC on the swing arm can be easily performed by the through hole formed on the head pullout FPC and the pin standing upright on the side surface of the swing arm.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. 1 and 2, 1 is a thin film magnetic head formed by a photolithography method, 2 is a floating slider on which the thin film magnetic head is mounted, 3 is a gimbal that is elastically supported and suspended by a suspension 4, and 25 is a thin film magnetic head. 1 is a suspension flexible printed circuit board (FPC) through transmission of an electric signal between 1 and an R / W AMP, 7 is a caulking mount for caulkingly supporting a rotatable carriage arm, and 9 is a coil pad of a thin film magnetic head.

The structure of the suspension FPC 25 is shown in FIG.
And it demonstrates using FIG. Suspension FPC25
Is a suspension FP made of heat resistant material such as polyimide
The base film 25-1 of C, the suspension FPC conductive member 25-2 involved in transmission of electric signals, and the purpose of covering and protecting the suspension FPC conductive member 25-2 formed on the suspension FPC base film 25-1. Of the suspension FPC film 25-3 (not shown), and the through holes 25-4 are provided for the purpose of electrical connection between the suspension FPC conductive member 25-2 and the coil pad 9 of the external thin film magnetic head. -1 is penetrated. Further, the through hole 25-4 is filled with a conductive substance, and a conductive protrusion (hereinafter, referred to as a head pump) 31 is formed on the suspension FPC conductive member 25-2.
And the suspension FPC base film 25-1 so as to project electricity from the outside, for example, the coil pad 9 of the thin film magnetic head. Above head bump 31
Conduction between the suspension FPC conductive member 25-2 and the suspension FPC is made possible by the conductive material filled in the through hole 25-4.

The suspension FPC 25 is formed in a shape having a triangular body similar to the suspension 4, a bifurcated angular portion in the head portion, and a tail portion extending in the longitudinal direction of the suspension FPC 25 in the rear portion. In the bifurcated portion, the head bumps 31 are formed at the ends of the respective corners so that two head bumps 31 are connected to the four thin-film magnetic heads 1, and the tip of the tail portion is for R / W AMP. FPC13
RDX / RDY pad 14 located in (FIGS. 4 and 6)
An AMP bump different from the above head bump for the purpose of conduction with
Two 26 are formed. Furthermore, the suspension F
The PC 25 has through-holes (suspension FPC through-holes (1) 28 and other through-holes (not shown)) formed in each of the bifurcated portion, main body portion, and tail portion. Suspension FPC 25 and arm 15, R / W AMP FPC for positioning with head and assembling carriage arm assembly
Positioning with 13 used. The inter-corner width W of the bifurcated corners matches the pitch between the two thin film magnetic heads formed on the side surface of the floating slider, and the tail length (L) is the same as that of the two tails formed at the tip of the tail. The AMP bumps 26 are formed on the RDX / RDY pads 14 formed on the R / W AMP FPC 13 disposed on the side surface of the carriage arm to have a length that can be overlapped when the carriage is assembled. The suspension FPC 25 is attached to the suspension 4 by using an adhesive member such as a double-sided tape after accurately positioning the suspension FPC 25 by the other through holes. The adhesive member may also be a member having a significant damping characteristic for mechanical vibration.

Next, a second embodiment of the present invention will be described with reference to FIG. The AMP bumps 26 formed on the tail of the suspension FPC 25 and the RDX / RDY pad 14 on the R / W AMP FPC 13 are electrically processed, and the suspension FPC 25 and the R / W AMP FPC 13 are connected to the carriage arm 19. The mounting and assembling method will be described. On the side surface of the carriage 19, four head bumps 31 are formed in a line at a pitch interval L. The head bumps 31 are collectively formed at the time of manufacturing the aluminum die casting of the carriage 19, and post-processing is unnecessary. Figure 4 shows the FPC13 for R / W AMP.
As shown in, the R / W AMP FPC near the RDX / RDY pad 14 has a hole diameter almost equal to the head bump diameter.
Four W AMP FPC through holes (hereinafter referred to as holes) 30 1
The rows are formed with a pitch L between holes. Also, a plurality of R
The hole 30 is formed so that the distance between the straight line connecting the centers of the DX / RDY pads and the straight line connecting the centers of the plurality of holes 30 is D.
And the RDX / RDY pad 14 is formed. A hole having a hole diameter substantially equal to the head bump diameter is also formed in the tail portion of the suspension FPC 25 at a position where the distance D from the straight line connecting the centers of the two AMPs 26 is.

FP for R / W AMP to carriage
The method for assembling and fixing C13 will be described first. As shown in FIG. 6, the four head bumps 31 formed on the side surface of the carriage arm are made to penetrate the four holes formed on the FPC 13 for R / W AMP, and the screw taps formed on the side surface of the carriage 19 are used. The FPC 13 for R / W AMP is positioned and fixed on the side surface of the carriage 19 with a screw. At this time, it is possible to reduce the number of assembly jigs and positioning jigs.

Next, the suspension FPC and RDX / RD
A method for conducting the connection with the Y pad 14 will be described. The R / W A
With the FPC 13 for MP fixed to the carriage, R
/ Suspension FPC from above FPC 13 for WAMP
25 tail holes (suspension FPC (through hole (1)) 28
To one of the head bumps 31. Suspension FPC25 belonging to the other three is also suspension FPC
The same processing is performed using the (through hole (1)) 28 and the bed bump 31. At this time, 4 sets of R / W AMP FPC 13 and 8 pieces of RDX / RDY pads 14 and 4 on which cream solder was previously applied
The eight AMP bumps 26 of each suspension FPC 25 are in superposed contact with each other, and the bump pads of the suspension FPC 25 are directly pressurized and heated, so that the conductive member of the suspension FPC 25 and the RDX / RDY of the R / W AMP FPC 13 are directly contacted with each other. Continuity processing with the pad 14 is easily completed without requiring work within the microscope field of view.

[0020]

As described above, according to the present invention, the wiring work of the head lead wire to the head pad is facilitated, the handling work requiring skill in the microscope field is reduced, the defect rate is improved, and the man-hours are reduced. It can be realized.

Further, according to the present invention, the conductive protrusions (bumps) formed on the FPC directly enable the electrical connection between the R / W amplifier head input terminal and the magnetic head, and the service pool by the conductive wire can be eliminated. Therefore, it is possible to prevent the pitching and rolling posture accuracy of the floating slider from being deteriorated due to the deformation during service loop forming. As a result, the flying characteristics of the floating slider can be improved, and the flying posture can be stabilized. Non-contact start / stop system
When adopting (for example, a ramp loading method), the loading characteristics of the floating slider can be significantly improved by improving the pitching / rolling posture accuracy.

Furthermore, in the present invention, since the R / W amplifier and the head lead-out line are electrically coupled by the conductive protrusions (bumps) formed on the head lead-out FPC, the RDX / RDY for the side face of the swing arm is connected. The work of soldering the conductive wire to the pad can be reduced, the work requiring skill in the field of view of the microscope can be eliminated from the assembly process, and the assembly man-hours can be significantly reduced to achieve cost reduction. Further, by forming the positioning through-hole formed on the head drawer FPC and the positioning pin upright on the side surface of the swing arm, the head drawer FPC can be easily positioned on the swing arm, and the head drawer FPC swings. Attachment to arm and pad for RDX / RDY and head drawer FP
The soldering work with C can be easily automated.

Further, according to the present invention, the head pull-out FPC is attached to the suspension supporting the magnetic head via the adhesive having the damping effect, so that the vibration mode of the suspension during the track movement of the magnetic head can be suppressed and the seek of the magnetic head can be suppressed. This has the effect of improving errors.

[Brief description of drawings]

FIG. 1 is a diagram showing a magnetic head gimbal assembly according to an embodiment of the present invention.

FIG. 2 is a partially enlarged view of the magnetic head gimbal assembly according to the first embodiment of the present invention.

FIG. 3 is a suspension FPC according to an embodiment of the present invention.
FIG.

FIG. 4 is an R / W AMP FP according to an embodiment of the present invention.
It is a partially expanded view of C.

FIG. 5 is a suspension FPC according to an embodiment of the present invention.
FIG.

FIG. 6 is a diagram showing a main part of a magnetic disk device according to a second embodiment of the present invention.

FIG. 7 is a diagram showing a first example of a conventional magnetic head gimbal assembly.

FIG. 8 is a diagram showing a second example of a conventional magnetic head gimbal assembly.

FIG. 9 is a bird's-eye view of the magnetic disk device.

FIG. 10 is a plan view of a magnetic disk device.

[Explanation of symbols]

1, 100 ... Thin film magnetic head, 2, 102 ... Floating slider, 3, 103 ... Gimbal, 4, 104 ... Suspension, 7, 107 ... Crimping mount, 9 ... Coil pad, 12, 112 ... Recording / reproducing amplifier (R / W AMP), 1
3,113 ... R / W FPC for AMP, 14,114 ... RDX
/ RDY pad, 15,115 ... Arm, 19,119 ... Carriage, 21,121 ... Bearing, 22,122 ... Shaft,
23,123 ... Voice coil motor (VCM) coil, 25 ...
Suspension FPC, 25-1 ... Suspension FPC
Base film, 25-2 ... Suspension FPC conductive member, 25-4 ... Through hole, 26 ... AMP bump, 28 ...
Suspension FPC through hole (1), 30 ... R / W AM
FPC / W AMP FPC through hole for P, 31 ... Head bump, 101 ... Magnetic head, 105 ... Conductive wire, 10
6 ... Hollow tube, 108 ... Hollow tube Crimping claw, 11
6 ... Magnetic disk, 117 ... Oscillating voice coil motor,
124 ... VCM magnetic circuit.

Claims (4)

[Claims] 1. A recording / reproducing amplifier (R / W AMP), an R / W AMP flexible printed circuit board (FPC) on which the R / W AMP is mounted, a magnetic disk, and recording / recording of digital information on the magnetic disk. A magnetic head for reproduction, a floating slider on which the magnetic head is mounted, a gimbal suspension for suspending the floating slider, and a member for transmitting electric signals between the magnetic head and the R / W AMP are flexible. Suspension FPC including an FPC having a
C is formed of two layers of a conductive member related to transmission of an electric signal and a base member that fixes and protects the conductive member. A through hole is formed in the base member, and a conductive material filling the through hole is formed. A conductive protrusion (bump) capable of conducting electricity with the conductive member is formed of a material, and has a coil forming the magnetic head and a magnetic head gimbal assembly capable of directly electrically coupling the conductive protrusion. A magnetic recording device characterized by the above. 2. An R / W AMP, an R / W AMP FPC equipped with the R / W AMP, and a magnetic disk,
A magnetic head that records and reproduces digital information on and from the magnetic disk, a floating slider that mounts the magnetic head, a gimbal suspension that suspends the floating slider, and an electrical connection between the magnetic head and the R / W AMP. The suspension FPC includes a flexible FPC that is a member for transmitting a signal, a suspension FPC, a conductive member that is related to the transmission of an electric signal, and a base member that fixes and protects the conductive member. Through holes are formed in the base member, and conductive protrusions (bumps) capable of conducting electricity with the conductive member are formed by a conductive material filling the through holes to form the magnetic head. And a magnetic head gimbal assembly capable of directly electrically coupling the coil and the conductive protrusion, The magnetic recording apparatus characterized by having the bump near the position regulating holes of the serial suspension FPC least two. 3. An R / W AMP, an R / W AMP FPC mounting the R / W AMP, and a magnetic disk,
A magnetic head that records and reproduces digital information on and from the magnetic disk, a floating slider that mounts the magnetic head, a gimbal suspension that suspends the floating slider, and an electrical connection between the magnetic head and the R / W AMP. The suspension FPC includes a flexible FPC that is a member for transmitting a signal, a suspension FPC, a conductive member that is related to the transmission of an electric signal, and a base member that fixes and protects the conductive member. Through holes are formed in the base member, and conductive protrusions (bumps) capable of conducting electricity with the conductive member are formed by a conductive material filling the through holes. Head signal terminal pad of an FPC for use with a magnetic head gimbal assembly to which the conductive protrusions can be directly electrically coupled. The magnetic recording apparatus, characterized by. 4. An R / W AMP, an R / W AMP FPC equipped with the R / W AMP, and a magnetic disk,
A magnetic head that records and reproduces digital information on and from the magnetic disk, a floating slider that mounts the magnetic head, a gimbal suspension that suspends the floating slider, and an electrical connection between the magnetic head and the R / W AMP. The suspension FPC includes a flexible FPC that is a member for transmitting a signal, a suspension FPC, a conductive member that is related to the transmission of an electric signal, and a base member that fixes and protects the conductive member. Through holes are formed in the base member, and conductive protrusions (bumps) capable of conducting electricity with the conductive member are formed by a conductive material filling the through holes. Head signal terminal pad of an FPC for use with a magnetic head gimbal assembly to which the conductive protrusions can be directly electrically coupled. At least one through hole for position regulation is provided near the bump of the base member, and a through hole for position regulation is provided near the head signal terminal of the R / W AMP FPC. The magnetic recording device according to claim 3.