JP2567884Y2 - Magnetic head device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head device suitable for writing or reading information signals on a floppy disk or the like.

[0002]

2. Description of the Related Art Conventionally, as a magnetic head device for a floppy disk, for example, a magnetic head device configured as shown in FIG. 7 has been proposed. In this magnetic head device, a gimbal 52 is provided with a magnetic head 51 having a magnetic head element having a recording / reproducing magnetic gap and an erasing magnetic gap sandwiched between a pair of sliders.

The magnetic head section 51 includes a front core 5 having a recording / reproducing magnetic gap and an erasing magnetic gap.
3, a back core 54 having a substantially E-shaped cross section, and coil bobbins 57 and 58 around which a drive coil is wound, in order to ensure a magnetic head element having a magnetic circuit portion, which ensures contact characteristics with a floppy disk. It is sandwiched between a pair of sliders 55 and 56 having a substantially L-shaped cross section. The front core 53 and the back core 54 are overlapped in a so-called stepped state within the coil bobbins 57 and 58 around which the drive coils are wound, and are pressed and supported by the core pressing member 59 so that magnetic coupling is achieved. Has become.

A plurality of slits 61 and 62 are provided in the magnetic head 51 having the above-described configuration while being fitted to a magnetic shield member 60 formed as a frame having a substantially rectangular cross section. The gimbal 52 is mounted on one surface. External terminals 63 and 64 provided on the coil bobbins 57 and 58 projecting from the slit 62 of the gimbal 52 to the other surface are electrically connected to the respective conductor patterns 66 of the printed wiring board 65.

In the above-described magnetic head device for a floppy disk, information signals are recorded and reproduced in a state where the floppy disk and the magnetic head are in contact with each other, so that static electricity is easily generated at the time of the contact. The static electricity causes an error as an overlap or an extra pulse with the recording / reproducing signal. Therefore, in this type of magnetic head device, the front core 53 is usually grounded on the drive circuit.

[0008] More specifically, as shown in FIG. 8, each leg of the front core 53, which partially faces each of the notches 67, 68, 69 provided on the gimbal 52, and the gimbal 52.
A conductive paint 70 for electrical connection is applied to the front core 53 and the front core 53 and the gimbal 52 are electrically connected. Further, as shown in FIG. 9, external terminals 63 protruding from the slits 62 of the gimbal 52,
64e of the conductor patterns 66 of the printed wiring board 65 are electrically connected to the lands 66a, 66b,.
The conductive paint 73 is applied over the earth land 72 a of the earth conductor pattern 72 for grounding provided on the gimbal 5 and the gimbal 52, and these are electrically connected. Thus, the front core 53 is connected to the ground conductor pattern 72 of the printed wiring board 65 via the gimbal 52, and is grounded on the drive circuit.

[0007]

In recent years, in order to further improve the recording density, a 4-Mbyte floppy disk drive has been developed to have a capacity of 4 Mbytes. In this 4-Mbyte floppy disk drive, the linear recording density is increased to 3 to increase the capacity.
The recording / reproducing gap is as narrow as 0.4 μm because it is 5 KBPI, which is 4 times the conventional 1 MB and twice the 2 MB.
The overwrite recording method (overwrite characteristic) performed by a floppy disk drive of 1 to 2 Mbytes cannot be performed, and a preceding erase method in which tracks are erased in advance during recording is adopted.

For this reason, in the magnetic head device of 4 Mbytes, the magnetic gap for recording / reproducing and the magnetic gap for erasing are reversed with respect to the magnetic head device of 1 to 2 Mbytes. That is, in a magnetic head device of 1 to 2 Mbytes, as shown in FIG. 8, one external terminal 63 is a magnetic head for recording / reproducing, and the other external terminal 64 is a magnetic head for erasing. In the magnetic head device described above, the recording / reproducing magnetic head side is the erasing magnetic head, and the erasing magnetic head side is the recording / reproducing magnetic head.

Regardless of the magnetic head device for 1 to 2 Mbytes or 4 Mbytes, the ground land 72a for grounding the front core 53 is generally fixed to either the recording / reproducing magnetic head side or the erasing magnetic head side. Therefore, when the printed wiring board 65 for 1 to 2 Mbytes is used in a 4 Mbyte magnetic head device, not only does the pattern shape of the conductor pattern 66 change, but the earth land 72 a is reversed. Therefore, it is necessary to manufacture a new printed wiring board for 4 Mbytes.

[0010] However, in order to manufacture a new printed wiring board, a considerable cost is required for a pattern printing (original) cost and a metal mold cost, and the cost must be borne each time a 4 Mbyte model is available. The connection between the gimbal 52 and the ground conductor pattern 72 is made by the conductive paint 7.
3, the reliability is low in terms of bonding strength.
Therefore, the present invention has been proposed in view of such a conventional situation, and can be used as a printed wiring board regardless of the model, and can provide a reliable grounding in terms of bonding strength. It is an object to provide a head device.

[0011]

In order to achieve the above object, a magnetic head device according to the present invention comprises a magnetic core forming a closed magnetic circuit via a magnetic gap and a coil bobbin fitted and disposed on the magnetic core. And a gimbal provided with a printed wiring board on which the magnetic head is mounted. The magnetic core is grounded to a grounding conductor pattern of the printed wiring board via an empty terminal of the coil bobbin. It is characterized by having been done.

[0012]

Generally, in a magnetic head device for a floppy disk, two windings are wound around a coil bobbin on the recording / reproducing side, and the winding start and end thereof and a common portion (common portion) of these two windings are provided. 3) are provided. On the other hand, one coil is wound around the coil bobbin on the erasing side, and there are two terminals for extracting the beginning and end of the winding.
A book is provided. Normally, the coil bobbin on the recording / reproducing side and the erasing side are commonly used. Therefore, three terminals are also provided on the coil bobbin on the erasing side. In the present invention, the unused terminal of the coil bobbin on the erasing side is used as a ground terminal.

That is, in the present invention, since the magnetic core is grounded to the grounding conductor pattern of the printed wiring board via the free terminal of the coil bobbin, it is not necessary to provide a grounding land portion on the printed wiring board. . Therefore, the directionality of the printed wiring board is lost, and a printed wiring board having the same shape can be used for the magnetic head devices of 1 to 2 Mbytes and 4 Mbytes. In the present invention, since the connection between the terminal and the conductor pattern,
Connection by soldering can be performed, and the joining strength at this portion is improved.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A specific embodiment to which the present invention is applied will be described below with reference to the drawings. In this embodiment,
This is an example in which the present invention is applied to a magnetic head device for a floppy disk which records and reproduces information signals on the floppy disk. As shown in FIG. 1, the magnetic head device according to the present embodiment has a magnetic head 1 having a magnetic head element having a recording / reproducing magnetic gap and an erasing magnetic gap sandwiched between a pair of sliders. It is mounted on a gimbal 3 on which a substrate 2 is provided.

As shown in FIG. 2, the magnetic head unit 1 has a front core 4 and a back core 5 which are magnetic cores forming a closed magnetic circuit via a magnetic gap, and is fitted to the front core 4 and the back core 5. A magnetic head element composed of coil bobbins 6 and 7 around which a driving coil is wound, a core pressing member 8 for magnetically coupling the front core 4 and the back core 5, and ensuring contact with the floppy disk And a pair of sliders 9 and 10.

The front core 4 has a substantially L-shaped side core portion 14 on both sides of a pair of rod-shaped center core portions 12 and 13 joined via a nonmagnetic material 11 so as not to interfere magnetically. , 15 have a first magnetic gap g ₁ and a second magnetic gap g ₂ on the abutting surface. This first magnetic gap g ₁ is
Operates as a recording and reproducing magnetic gap, the second magnetic gap g ₂ is made to operate as a magnetic gap for erasing.

On the other hand, the back core 5 includes a pair of core members 1 formed corresponding to the core shape of the front core 4.
6 and 17 are joined by a side surface side via a non-magnetic material 18. The core members 16, 17
Has center legs 19 and 20 and side legs 21 and 22 at positions facing the center core portions 12 and 13 and the side core portions 14 and 15 of the front core 4, and are connected by connecting members 23 and 24. The planar shape is substantially U-shaped. Therefore, the center leg 1
By providing 9, 20 and side legs 21, 22,
It is possible to secure a bonding area between the cores that increases the length of the front core 4 in the depth direction, and it is possible to improve the electromagnetic conversion characteristics.

The coil bobbins 6 and 7 have external terminals 25a, 25b and 25 formed by stamping a hoop material.
c and 26a, 26b, 26c by insert molding. A predetermined number of drive coils 27 are wound around the coil bobbin 6 through which the side core portion 14 of the front core 4 on which the erasing magnetic gap (the first magnetic gap g ₁ ) is formed is wound. Are wound around the external terminals 25a and 25b, respectively. On the other hand, a predetermined number of two drive coils 28 are wound around the coil bobbin 7 through which the side core portion 15 of the front core 4 on which the recording / reproducing magnetic gap (second magnetic gap g ₂ ) is formed is inserted. , The beginning and end of the winding, and the common part (common) each have three external terminals 26.
a, 26b, 26c.

The front core 4 and the back core 5 are connected to the side cores 14 and 15 of the front core 4 and the side legs 21 and 22 of the back core 5 in the through holes 6a and 7a of the coil bobbins 6 and 7, respectively. Are superposed in a so-called stepped state. That is, the side core portion 14
The side surface 14a and the side surface 21a of the side leg portion 21 are in contact with each other, and the side surface 15a of the side core portion 15 and the one side surface 22a of the side leg portion 22 are in contact with each other, thereby achieving magnetic coupling. Is configured. Therefore, the front core 4, the back core 5, and the coil bobbins 6 and 7 operate as a first magnetic gap for recording and reproduction.
Magnetic gap g ₁ magnetic head element having a, that is a recording and reproducing head, a second magnetic gap g ₂ of the magnetic head device having operating as erasing magnetic gap, i.e. the erase head is constructed of.

The through holes 6 of the coil bobbins 6 and 7
A pair of core pressing pieces 29 and 30 of a core pressing member 8 for magnetically coupling the front core 4 and the back core 5 are inserted into the a and 7a. The core pressing member 8 includes a receiving portion 31 for a head pressing member (pivot) of a magnetic head support mechanism (not shown) provided on the back side of the magnetic head element, and the side core portions 14 and 1.
5 and the coil bobbin 6, together with the side legs 21, 22
7 comprises core pressing pieces 29, 30 inserted into the inside.

The receiving portion 31 is provided at a substantially central portion of a connecting plate 32 having a receiving surface 31a of the pressing member so as to hang down in a contacting direction of the pressing member, and serves as a support for an impact of the pressing member. I have. On the other hand, the core holding pieces 29, 30
A thin plate hangs at both ends along one side edge of the connecting plate 32 in the same direction as the receiving portion 31 so that the connecting plate 32
Are provided integrally. The core holding piece 2
The distal end portions 9 and 30 are formed in a substantially circular arc shape so that they can be easily inserted into the coil bobbins 6 and 7 and the workability can be improved. The core pressing member 7
Since it plays a role of alleviating the impact from the head pressing member, it is preferably molded from a relatively plastic plastic such as polyacetal resin or ABS resin.

The surfaces of the core pressing pieces 29 and 30 opposite to the surface facing the magnetic head element, that is, the surfaces opposite to the surfaces of the back core 5 and the side leg portions 21 and 22 are provided. Protrusions 33 and 34 having a semiconical shape for making the front core 4 and the back core 5 adhere to each other are formed. Therefore, in the coil bobbins 6 and 7, the protrusions 33 and 34 provided on the core pressing pieces 29 and 30 are provided.
Abuts against the inner wall surfaces of the coil bobbins 6 and 7 to elastically deform the core pressing pieces 29 and 30 toward the back core 5, and the elastic force causes the core pressing pieces 29 and 30 to move to the side leg portions 21 of the back core 5. , 22 are pressed and supported. As a result,
The side leg portions 21 and 22 of the back core 5 and the side core portions 14 and 15 of the front core 4 are pressed and supported in close contact with each other, and the magnetic and mechanical coupling between the front core 4 and the back core 5 is ensured. It will be. Therefore, no gap is formed between the front core 4 and the back core 5, and the gap does not operate as a back gap when the magnetic head is driven.

The magnetic head element having the above-described structure constitutes the magnetic head unit 1 by being sandwiched between a pair of sliders 9 and 10 for securing the contact characteristics with the floppy disk. That is, the first magnetic gap g ₁ and the second magnetic gap g of the magnetic head element
_The magnetic head unit 1 is constituted by providing a pair of sliders 9 and 10 having a substantially L-shaped cross section on both side surfaces of the front core 4 provided with _{2 on} the sliding surface side with the floppy disk.

The magnetic head 1 constructed as described above is mounted on one surface 3a of the gimbal 3 while being fitted to a magnetic shield member 35 formed as a frame having a substantially rectangular cross section. It is supposed to be. The gimbal 3 includes a head mounting unit 36 on which the magnetic head unit 1 is mounted.
And a plurality of slits 37 and 38 cut out so that the magnetic head unit 1 mounted on the head mounting unit 36 can be moved in the front-rear and left-right directions in response to an impact or the like. The head mounting portion 36 is provided with cutout portions 36a, 36b, 36c for facing a part of the front end portions of the center core portions 12, 13 and the side core portions 14, 15 of the magnetic head element. I have.

With respect to the gimbal 3 formed as described above, the magnetic head unit 1 moves the slider 9 and the slider 9 as shown in FIG.
10, the front end portions 9a, 10a and the front end portions 12a, 13a, 14b, 15b of the center core portions 12, 13 and the side core portions 14, 15 of the front core 4 are provided so as to contact the head mounting portion 36. And a magnetic shield part 3 fitted around the outer periphery of the magnetic head part 1.
5 is fixed by an adhesive (not shown) applied over the gimbal 3 and the side wall. External terminals 25a, 25b, 25c and 26 provided on the respective coil bobbins 6, 7 of the magnetic head unit 1 mounted on the gimbal 3
a, 26b, 26c have slits 38,
38 protrudes toward the surface 3b opposite to the mounting surface of the magnetic head unit 1. Also, the front end portions 12a, 13a and 1 of the center core portions 12 and 13 and the side core portions 14 and 15 of the front core 4 that come into contact with the head mounting portion 36, respectively.
Parts 4b and 15b face the respective cutouts 36a, 36b and 36c provided at positions opposed thereto.

The above notches 36a, 36
b and 36c, the front end portions 12a and 13a and 14b and 15b of the center core portions 12 and 13 and the side core portions 14 and 15 of the front core 4 and 15b, respectively,
A conductive paint 39a is applied over the gimbal 3 and is electrically connected to the gimbal 3. In addition, a conductive paint 39b is applied to the vacant terminal 25c provided on the coil bobbin 6 through which the side core portion 14 of the front core 4 and the side leg portion 21 of the back core 5 where the magnetic gap for erasure is provided are inserted. Similarly, the connection with the gimbal 3 is established electrically. Therefore,
The front core 4 is connected to the empty terminal 2 via the gimbal 3.
5c.

The external terminals 25a, 25b, 25c, 26 of the magnetic head 1 mounted on the gimbal 3
a, 26b, 26c are the printed wiring boards 2 shown in FIG.
Conductor patterns 40a, 40b, 4 corresponding to
0c, 40d, and 40e are inserted through the through holes, and FIG.
As shown in FIG. 7, the solder 41 is attached to the electrical connection. Specifically, the external terminal 26a of the coil bobbin 7 on the recording / reproducing side has the conductor pattern 40c, the external terminal 26b has the conductor pattern 40b, and the external terminal 26c
Are connected to the conductor pattern 40a. On the other hand, the external terminal 25a of the coil bobbin 6 on the erasing side is
c, the external terminal 25b is connected to the conductor pattern 40d, and the empty terminal 25c is connected to the conductor pattern 40e. The conductor pattern 40e connected to the empty terminal 25c is a grounding conductor pattern grounded on the drive circuit. Therefore, the front core 4 is electrically connected to the grounding conductor pattern 40e of the printed wiring board 2 via the free terminal 25c, and is grounded on the drive circuit.

As described above, the ground of the front core 4 is connected to the printed wiring board 2 via the empty terminal 25c of the coil bobbin 6.
When electrically connected to the grounding conductor pattern 40e, it is not necessary to separately provide a grounding ground land, and the land portion of the grounding conductor pattern 40e is formed in the same shape as the land portion connected to a normal external terminal. They can have the same shape. Therefore, the directionality of the printed wiring board 2 is lost, and the printed wiring board 2 having the same shape has a size of 1-2.
It can correspond to a magnetic head device of M bytes and 4 M bytes.
That is, in the magnetic head device of 1 to 2 Mbytes and the magnetic head device of 4 Mbytes, the magnetic head for recording / reproducing and the magnetic head for erasing are reversed. Vacant terminal of the coil bobbin, and the vacant terminal is connected to the grounding conductor pattern 4.
By connecting 0e, the printed wiring board 2 can be shared. Further, the vacant terminal 25c and the grounding conductor pattern 40e are used.
Is connected by the solder 41, so that the bonding strength at this portion is increased and the reliability is improved.

In order to manufacture the magnetic head device having the above configuration, first, the magnetic head unit 1 is manufactured. That is, the coil bobbins 6, 7 are connected to the side core portions 14,
15, and then the side legs 21 and 22 of the back core 5 are inserted into the coil bobbins 6 and 7.
After inserting the core pressing pieces 29 and 30 of the core pressing member 8 into the coil bobbins 6 and 7 by pressing them, the sliders 9 and 10 are bonded and fixed to both sides of the front core 4. Then, the magnetic shield member 35 is attached to the magnetic head 1 so as to surround the outer periphery of the sliders 9 and 10.
In this state, it is mounted on the gimbal 3 and fixed with an adhesive.

Next, conductive paints 39a and 39b are applied to the front end of the front core 4 in contact with the gimbal 3 and the gimbal 3, and also to the free terminal 25c of the coil bobbin 6 for erasing and the gimbal 3. This empty terminal 2
Conductive paint 39b for connecting 5c and gimbal 3
Can be applied in the same step for establishing an electrical connection between the front core 4 and the gimbal 3, thereby eliminating the complexity of performing a separate step as in the prior art.

Next, the external terminals 25a, 25b,
25c, 36a, 36b, 36c to the printed wiring board 2
Conductor patterns 40a, 40b, 40c, 4
Solder 41 is attached to 0d and 40e to achieve electrical connection. The connection between the unoccupied terminal 25c and the conductor pattern 40e is slightly inferior to the connection by the solder 41, but may be applied with a conductive adhesive or a conductive paint. As a result, the front core 4 is connected to the ground conductor pattern 40e via the empty terminal 25c, and is grounded on the drive circuit.

As described above, an example of the magnetic head device to which the present invention is applied has been described. However, the present invention can be variously modified without being limited to the above-described embodiment. In the above example, the front core 4 is grounded, but the same effect can be obtained by grounding the back core 5. In addition, as shown in FIG.
An opposing portion of the gimbal 3 corresponding to the land portion of e may be protruded, and a conductive paint 42 may be applied to this portion to be electrically connected to the grounding conductor pattern 40e. In this case, it is necessary to remove the empty terminal 25c provided on the coil bobbin 6 on the erasing side.

[0033]

As is clear from the above description, according to the present invention, the magnetic core is electrically connected to the grounding conductor pattern of the printed wiring board via the empty terminal of the coil bobbin to be grounded. Therefore, it is not necessary to separately provide an earth land for grounding, and the directivity of the printed wiring board is lost. Therefore, a printed wiring board having the same shape can be used for any of magnetic head devices for 1-2 Mbytes and 4 Mbytes, and a common printed wiring board can be achieved.

As a result, it is not necessary to newly produce an original plate and a mold for pattern wiring for producing a printed wiring board, and it is possible to greatly reduce the cost of the mold. Also,
In the magnetic head device of the present invention, the connection between the free terminal and the printed wiring board is soldered, so that the reliability is further improved in terms of bonding strength.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing an example of a magnetic head device to which the present invention is applied.

FIG. 2 is an exploded perspective view of a magnetic head unit.

FIG. 3 is a perspective view showing a state in which a magnetic head unit is mounted on a gimbal.

FIG. 4 is a perspective view showing a state in which a printed wiring board is attached to external terminals of a magnetic head unit.

FIG. 5 is a perspective view showing a state in which a conductor pattern of a printed wiring board is solder-connected to an external terminal of the magnetic head unit.

FIG. 6 is a diagram showing another example of grounding the front core.

FIG. 7 is an exploded perspective view showing an example of a conventional magnetic head device.

FIG. 8 is a perspective view showing a state in which a magnetic head unit of a conventional magnetic head device is mounted on a gimbal.

FIG. 9 is a perspective view showing a state in which a printed wiring board is attached to a magnetic head portion of a conventional magnetic head device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Magnetic head part 2 ... Printed wiring board 3 ... Gimbal 6, 7 ... Coil bobbin 25c ... Empty terminal 40e ... Grounding conductor pattern

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hideko Matsumoto 6-5-6 Kita-Shinagawa, Shinagawa-ku, Tokyo Inside Sony Magne Products Co., Ltd. (56) References JP-A-61-243903 (JP, A) JP-A-1-184605 (JP, A) JP-A-2-58722 (JP, A) JP-A-2-35320 (JP, U) JP-A-1-133308 (JP, U) JP-A-2 84115 (JP, U) Hikaru 4-6803 (JP, U)

Claims (1)

(57) [Scope of request for utility model registration] 1. A magnetic head comprising a magnetic core forming a closed magnetic circuit via a magnetic gap and a coil bobbin fitted and arranged on the magnetic core, and a printed wiring board on which the magnetic head is mounted. A magnetic gimbal, wherein the magnetic core is grounded to a grounding conductor pattern of the printed wiring board via an empty terminal of the coil bobbin.