JPH0722734Y2 - Magnetic head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION << Industrial Application Field >> The present invention relates to a magnetic head used in a floppy disk device or the like, and more particularly to a structure in which electrical connection for grounding between a flexure and a printed circuit board is ensured.

<< Prior Art >> A magnetic head used in a floppy disk device or the like has a conventional structure shown in FIGS.

In the figure, 10 is a flexure, 12 is a magnetic head main body fixed to the lower central surface of the flexure 10, and 14 is a flexible printed circuit board fixed to the flexure 10.

The printed circuit board 14 is formed with a plurality of conductive patterns 14a for connecting a plurality of lead wires 12a derived from the magnetic head body 12 side, and each conductive pattern 14a.
A conductive pattern 14b for grounding is formed on the outer side of the.

Then, the connection electrode portion 14b-1 of the ground conductive pattern 14b
As shown in FIG. 6 (a), a conductive adhesive 16 is dropped between the flexure 10 and the flexure 10 to electrically connect the flexure 10 and the conductive pattern 14b in a bridge shape,
Static electricity generated when the disk is accessed is grounded from the flexure 10 side to the outside of the disk device through the grounding conductive pattern 14b.

<< Problems to be Solved by the Invention >> However, in the case of this connection structure, the conductive adhesive 16 may not necessarily bridge between them, as shown in FIG. 6 (b), for example. On the other hand, if the dropping position is bad, the conductive paint 16 may be rolled into a ball shape and not contact the flexure 10 side, or conversely may be supplied to the flexure 10 side but not contacting the connection electrode portion 14b-1. This is one of the factors that reduce the yield.

In addition, in order to eliminate such a problem, it is necessary to increase the amount of conductive adhesive supplied to eliminate the connection failure, and there is a drawback that the amount of adhesive consumption is larger than the required amount.

The present invention solves the above problems, and an object thereof is to provide a structure capable of reliably connecting the connection electrode portion of the grounding conductive pattern and the flexure.

<< Means for Solving Problems >> In order to achieve the above object, the present invention provides a magnetic head main body fixed to a central lower surface of a flexure and a printed wiring board having one end fixed to the upper surface of the flexure by adhesion. In a magnetic head provided with: a projection is provided on the periphery of a mounting position of the printed wiring board of the flexure, and a recess for engaging with the projection is formed in the printed wiring board, and the printed wiring is provided around the recess. The connection electrode portion of the grounding conductive pattern formed on the plate is arranged, and the conductive material for adhesion is interposed in the gap between the connection electrode portion and the protrusion to electrically connect the connection electrode portion and the protrusion. The idea is to connect to.

<< Operation >> According to the above configuration, when the printed wiring board is wired by the flexure, the engaging portions provided on the printed wiring board are arranged so as to be coded with the protrusions provided on the flexure. Then, since the grounding conductive pattern is located around the engaging portion, the conductive pattern and the protrusion are located close to each other. Since the protrusion and the flexure are integrated, the conductive pattern and the protrusion are electrically connected by a conductive material, so that the grounding between the conductive pattern and the flexure can be surely obtained.

Further, by coding the protrusion and the engaging portion, the installation position of the printed wiring board with respect to the flexure can be relatively easily and accurately attached.

<< Embodiment >> An embodiment of the present invention will be described below in detail with reference to the drawings.

In FIGS. 1 to 4, 30 is a flexure, 32 is a magnetic head fixed to the lower surface of the flexure 30, and 34 is a flexible printed circuit board which is a printed wiring board having one end fixed to the upper surface of the flexure 30.

The flexure 30 is made of a plate-shaped spring material, and is formed with a slit 36 forming a gimbal support shape on the periphery by press molding or etching.
The flexure 30 is divided into a peripheral portion 30a and a central portion 30b at 36,
Further, a pair of openings 38 communicating with each other via a narrow groove 38a is formed in the center of the inner part 30b.

The magnetic head main body 32 is fixed to the lower surface of the central portion 30b of the flexure 30, and is provided with a slider 40 that constitutes a sliding contact surface for a floppy disk or the like, and is arranged so as to project on the slider 40. Part 30b
Of the three core leg pieces 42 projecting to the upper part of the
It is composed of a pair of coils 44 inserted through and fixed to the core leg pieces 42 on both sides projecting above the flexure 30.

The flexible printed circuit board 34 is formed by forming a plurality of conductive patterns 34b for connecting lead wires on the surface of a base film 34a having insulation and flexibility such as polyimide and a conductive pattern 34c for grounding on the outer side thereof. Yes,
The end edge of the base film 34a facing the opening 38 is formed in a shape having a recess in the center according to the shape of the opening 38 to be expanded. The connection electrode portion 34b-1 of the conductive pattern 34b for line connection is located.

Further, the connection electrode portion 34d-of the grounding conductive pattern 34c-
1 is located on the side portion of the base film 34a.

On the other hand, on the side of the adhesive surface 30b-1 of the central portion 30a with respect to the flexible printed circuit board 34, the protrusion 50 is formed so as to project partially inside the adhesive surface 30b-1 by etching or punching. Corresponding to the protrusion 50, a semicircular notch 52, which is a recess, is formed on the outer side of the flexible printed circuit board 34.
The connection electrode portion 34c-1 is formed so as to surround 52.

Then, the flexible printed circuit board 34 is attached to the flexure 30.
When it is mounted on the flexure 30, the projection 50 provided on the flexure 30 is aligned with the notch 52 provided on the flexible printed circuit board 34. In this state, the connection electrode portion 34c-1 for grounding and the projection 50 are as shown in FIG. 4 (a) (when the flexure 30 is etched) or (b) (when the flexure 30 is pressed). , They are extremely close to each other, and a V-shaped gap is formed between them.

Therefore, if the conductive adhesive 60 is dropped into the V-shaped gap, it is possible to surely obtain electrical conduction between the two.

Moreover, since the protrusion 50 and the notch 52 are substantially the same,
Since a relatively wide area around 50 and the end face of the notch 52 are arranged so as to face each other, the contact between the two can be more reliably performed.

Further, in this embodiment, the flexible printed circuit board 34 is attached to the flexure 30 so that the projection 50 and the notch 52 are aligned with each other.
The projection 50 and the notch
By forming 52, the mounting position of the flexible printed circuit board 34 on the flexure 30 is accurately determined.

Further, in this embodiment, the expanded end edges 34d are fixed to the upper surface of the central portion 30b in an overhang-like state by providing a predetermined protrusion allowance d on the inner peripheral side of each opening 38. It is supposed to do.

Next, in a fixed state, each of the expanded end edges 34d is connected to each of the openings 3
A plurality of lead wires 44 led out from each coil 44, which are accurately opposed to each other with a predetermined gap provided on the outer peripheral portions of the pair of coils 44 protruding above the flexure 30 through 8.
The lead-out end portion of a is connected to the connection electrode portion 34b-1 of each conductive pattern 34b formed on the flexible printed board 34 by soldering 46.

The coils 44 are core leg pieces that project onto the openings 38 after the flexible printed circuit board 34 is bonded to the flexure 30 and the slider 40 is fixed.
The lead wires 44a are inserted into the lead wires 42a, but at the time of this insertion, the lead wires 44a are also drawn into the lower part of the opening 38.
The openings 44a contact the respective expanded end edges 34d protruding inside the respective openings 38.

Then, this contact portion is formed by the insulating base film 34a.
Therefore, there is little possibility of damage to the insulating coating of the lead wire 44a due to contact, and even if the insulating coating is damaged, for example, since this portion maintains the insulating property, the insulating property is not impaired, The short circuit phenomenon can be structurally eliminated.

In this embodiment, only one side surface of the printed board 34 is positioned by fitting the protrusion 50 and the notch 52, but if the flexible printed board 34 is provided on both sides, the positioning accuracy is further improved. Needless to say, the grounding conductive patterns 34c may be formed on both sides of the printed circuit board 34 accordingly.

Alternatively, the conductive adhesive 60 may be replaced by soldering to connect the two.

Furthermore, in the above-mentioned embodiments, the description has been given only to the case where the expanded edge 34d of the printed circuit board 34 is located inside the opening 38 of the flexure 30, but the present invention is not limited to this and the opening 38 It can be applied even when it is located outside the.

Furthermore, the shape of the protrusion 50 is arbitrary, and the component is not limited to one integrally formed with the flexure by pressing or the like, and other parts may be separately prepared and arranged by adhesion or welding.

The shape of the recess is not limited to the above-mentioned cutout, and may be a through hole.

Although the flexible printed circuit board having flexibility is used as the printed wiring board in each of the above-described embodiments, the present invention is not limited to the above-described embodiment and is made of, for example, a relatively hard material. A flat printed board may be used.

<< Effects >> As described in detail with reference to the embodiments above, in the magnetic head according to the present invention, the printed circuit board is bonded to the flexure side with the recesses fitted in the protrusions, and the conductive adhesive material is used in the recesses. Since it will be interposed in the gap between the earth connection electrode part around the and the above-mentioned protrusion, even if the amount of the conductive material for adhesion is smaller than in the conventional case, both can be surely electrically connected, and A poor connection can be prevented, and a decrease in product yield due to this can be prevented. Further, the projections and the recesses can be engaged with each other to perform the alignment, and the adhesive attachment can be reliably and accurately performed at the desired mounting position.

[Brief description of drawings]

1 to 4 show a magnetic head according to the present invention, FIG. 1 is an exploded perspective view of the magnetic head, FIG. 2 is a plan view showing an assembled state of the magnetic head, and FIG. 3 is a sectional view thereof. 4 (a) and 4 (b) are cross-sectional views of a main part, FIGS. 5 and 6 show a conventional example, FIG. 5 is an exploded perspective view of a magnetic head, and FIGS. 6 (a) and 6 (b). [Fig. 4] is a cross-sectional view of a main part showing a disadvantage of the conventional fixing structure. 30: flexure, 30a: central part 32: magnetic head body 34: flexible printed circuit board 34c ... conductive pattern for ground 34c-1 ... connecting electrode part, 38 ... opening 44 ... coil 44a .... Lead wire 50 …… Positioning protrusion 52 …… Positioning notch 60 …… Conductive adhesive

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Yoshinori Nakamura 5 36-11 Shimbashi, Minato-ku, Tokyo Fuji Electric Kagaku Co., Ltd. (72) Tsukasa Tsukadate 5 36-11 Shimbashi, Minato-ku, Tokyo Fuji (56) Reference JP 61-144712 (JP, A) JP 59-146478 (JP, A) JP 61-76512 (JP, U)

Claims (1)

[Scope of utility model registration request] 1. A magnetic head comprising a magnetic head main body fixed to the central lower surface of a flexure and a printed wiring board having one end fixed to the upper surface of the flexure by adhesion, at the periphery of the printed wiring board mounting position of the flexure. A protrusion is provided so as to project, a recess is formed in the printed wiring board so as to engage with the protrusion, and a connection electrode portion of a grounding conductive pattern formed on the printed wiring board is arranged around the recess. A magnetic head, wherein the connection electrode portion and the protrusion are electrically connected by interposing an adhesive conductive material in a gap portion between the connection electrode portion and the protrusion.