JPS62204409A - Magnetic head and its manufacture - Google Patents

Abstract

PURPOSE:To heighten accuracy of assembling, simplify process and improve durability at the time of using by forming a groove in the direction of tracks on the front face of a core block made by unifying a read write core, an intermediate core and an erase core, and providing a read write gap and erase gaps. CONSTITUTION:A magnetic head is formed by unifying a read write core 2, an intermediate core 4 and an erase core 3, and the read write core 2 and erase core 3 are formed of material such as ferrite etc. The read write core 2 and erase core 3 are nearly L-shaped and unified by butting to hold the intermediate core 4 by a read write front core section 21 and an erase front core section 31, and forms a core block 1. The first grooves 210, 220 for determining the width of a read write gap 71 and the second grooves 310, 320 for determining the width of erase gaps 75, 76 are formed on the front face of the core block 1 of the magnetic head.

Description

[Detailed description of the invention]

BACKGROUND OF THE INVENTION Technical Field The present invention relates to a magnetic head, particularly a tunnel erase type floppy head. Prior art and its problems For example, the shape of magnetic heads for recording, reproducing, and erasing information on flexible recording media has been optimally designed to suit each company's drive, and various types have been proposed. . In this case, the basic characteristics required are almost the same, but recently, especially recording density,
With the increase in track density and the compactness of flexible recording media, there is a strong demand for higher output by increasing the magnetic efficiency of magnetic heads, miniaturization, and simplified assembly processes. An example of the conventional magnetic head structure is shown in Fig. 16 and Fig. 1.
This is a tunnel erase type magnetic head, usually called a bulk type, as shown in Figure 7. In this case, the read/write core 2 and the read/write intermediate core 45 are formed by abutting half-core blocks made of a material such as ferrite, and have a read/write gap 71 on the front surface that slides into contact with the magnetic recording medium. The read/write gap 71 has nonmagnetic material filling portions 81.82 at both ends on the outside in the track width direction, and the nonmagnetic material filling portions 81.82 determine the track rjl of the read/write gap. It is something to do. The read/write head portion including the non-magnetic material filling portions 81 and 82 is constructed by butting the read/write core 2, which has a groove for determining the track [11] on the front surface, with the read/write intermediate core 45. It is created by filling the groove with a non-magnetic filler such as glass. A winding 91 is provided on the read/write side core portion of this read/write head. Further, the erase core 3 and the erase intermediate core 46 are also made of a material such as ferrite, and have erase gaps 75 and 76 on the front surface that slides into contact with the magnetic recording medium at the abutting surface of the erase core 3 and the erase intermediate core 46. The erase gaps 75 and 76 are located in a substantially symmetrical position across the non-magnetic material filled portion 85 in the center. This non-magnetic material filling portion 85 is usually substantially the same as the track 1 of the read/write gap 71 described above. In addition, the erase gap track (1) is provided with non-magnetic material filling portions 86.8 provided at both ends of both outer sides in the direction of one track.
7. The erase head portion including the non-magnetic material filling portions 85, 86, 87 is constructed by filling the erase core 3 with a non-magnetic filler after abutting the erase core 3, which has a predetermined groove formed on its front surface, against the erase intermediate core 46. has been created. In addition, the erase side core portion 35 of this erase head
A winding 95 is attached to the wire. Then, the core block 1 is formed by integrating the integrated body of the read/write core 2 and the read/write intermediate core 45 and the integrated body of the erase core 3 and the erase intermediate core 46 via the insulating layer 6. are doing. The core block 1 is further sandwiched and fixed on both sides in the longitudinal direction by sliders 15 and 16. Such conventional magnetic heads have various disadvantages. In particular, it is difficult to improve the accuracy of read/write tracks and erase tracks, and the number of steps is large, which is an obstacle to lowering costs. II. Purpose of the Invention The purpose of the present invention is to achieve high assembly accuracy, simple steps,
Another object of the present invention is to provide a magnetic head that has excellent durability during use and a method for manufacturing the same. (2) Disclosure of the Invention These objects are achieved by the present invention as described below. That is, the first invention is a read/write core. It has a core block that integrates an intermediate core and an erase core, and in the track direction on the front surface of the core block,
It has a first groove extending from the front surface of the intermediate core to the end surface of the core block on the read/write core side, and the track Ill of the read/write gap on the abutting surface of the read/write core and the intermediate core is regulated by this groove. , in the track direction of the front surface of the core block, from the front surface of the intermediate core to the end surface of the core block on the erase core side.
This magnetic head is characterized in that the track width of the erase gap on the abutting surface between the intermediate foot and the erase core is regulated by the groove. Further, the second invention provides a first groove in the front surface of a core block material in which a read/write core material, an intermediate core material, and an erase core material are integrated. A second groove is provided in the track direction from the front surface of the read/write core or intermediate core to the end surface of the core block material on the erase core side, and then the front surface of this core block material is polished. This method of manufacturing a magnetic head is characterized in that a core block is obtained in which the track opening of the read/write gap is regulated by the groove, and the track width of the erase gap is regulated by the second groove. ①Specific structure of the invention The specific structure of the present invention will be explained in detail below. Embodiments of the magnetic head of the present invention are shown in FIGS. 1-7. In this case, the magnetic head of the present invention includes a read/write core 2,
It is formed by integrating the intermediate core 4 and the erase core 3. The read/write core 2 and erase core 3 are made of a material such as ferrite. The read/write core 2 and the erase core 3 have an L-shape, and are butted and integrated at the read/write front core part 21 and the erase front core part 31 so as to sandwich the intermediate core 4. A core block 1 is formed as shown in FIGS. 1, 2, and 7. As a method for fixing and adhering the read/write core 2, intermediate core 4, and erase core 3, glass bonding or the like may be used. The intermediate core 4 is also made of a material such as ferrite, and is preferably made of the same material as the read/write core 2 and the erase core 3. In this case, the read/write core 2 has a flat plate shape with a thickness of about 0.2 to 0.8 mm in the track width direction. Further, the length of the read/write front core section 21 is 1.0 to 3.0.
The length of the read/write side core portion 25 is approximately 2.0 mm.
It should be about 0 to 5.0 mm. The length of the intermediate core 4 in the track direction is 0.2 to 1.0 m.
m, the thickness in the track width direction is almost the same as the read/write core 2, and the length is the read/write side core part 25.
It has almost the same flat plate shape. Further, the erase core 3 has a flat plate shape with substantially the same thickness in the track width direction as the read/write core 2 and the intermediate core 4. In addition, the length of the erase front core portion 31 is 1.0
~3.0mm, and the length of the erase side core portion 35 is approximately 2.0~5.0mm. It should be about 0mm. Then, the read/write front core section 21 and the intermediate core 4
The abutting surface has a gap of 0.5 to 2. OILm
It has a read/write gap 71 of about 2.0 Lm, and two erase gaps 75.76 of about 2.0 to 5.0 Lm are usually provided on the abutting surfaces of the erase front core part 31 and the intermediate core 4. There is. As a gap material, 5to2. Use non-magnetic material such as glass. In addition, as shown in Figure 1, the read/write front core section 21
The bottom side of the erase front core portion 31 that is connected to the gap abutting surface is tapered, and so-called apex portions (APEX) 120 and 130 are provided. The apex portions 120 and 130 are filled with a non-magnetic filler such as glass. As shown in FIGS. 4 to 7, the magnetic field of the present invention includes first grooves 210, 220 for determining the width of the read/write gap 71 and an erase gap 75.
Second grooves 310, 320, 3 for determining the width of 76
30 is formed on the front surface of the core block 1. The first and second grooves will be explained in accordance with the manufacturing process thereof. First, a core blowing material 10 for forming grooves corresponding to the core block is prepared. As one embodiment of the core block material 10 is shown in FIG. Formed as a single unit. Next, grooves are formed in this core block material 10, but the grooves can be formed in various ways, and an example is given below. Grooves 310, 320, 330, 210, 220 are 4th-A
As shown in FIGS. 4-B, 5, 6-A, 6-B, and 6-C, the read/write core material 2
0 or the front surface of the erase core material 30 to reach the end surface of the core block on the erase core side or the read/write core side. In this case, the first grooves 210 and 220 are inclined grooves that extend from the front surface of the erase core material 30 to the end surface of the read/write core material 20 in the track direction. Also,
Second grooves 310, 320, and 330 are inclined grooves extending from the front surface of the read/write core material 20 to the end surface of the erase core material 30 in the track direction. In FIG. 4-A, the distance a in the track width direction between the groove 210 and the groove 220 is about 0.1 to 0.3 mm, and the second groove 3
The width of 30 is about 0.1 to 0.3 mm, grooves 210, 22
The length in the track direction of 0,310°320.330 is 1
．． 0-5. It is about 0mm. The width of the first grooves 210, 220 is about 0.05 to 0.2 mm, and the width of the second grooves 310 and 320, which are provided as necessary, is 0.01 to 0.2 mm. It is about 0.1 mm. The track width of the read/write gap 71 is determined by the distance a between the first grooves 210 and 220.
Also, depending on the distance between the second groove 330 and the second grooves 310 and 320, the erase gap 75.
] is determined, and this track width is usually 0.05 to 0.
．． It is about 2 mm. In addition, in FIG. 4-B, broken lines gl indicating the bottoms of the first grooves 210 and 220 and the second grooves 31
The depth X into which the broken lines g2 indicating the bottoms of 0, 320 and 330 are embedded into the apex portions 120 and 130, respectively, is 0.
The distance 1ty between the intersections u and m between gl and g2 and the intermediate core material 40 is approximately 0.1 to 0.2 mm, and the front of the core block material 10 at both ends of the core block material 10 in the track direction. gl and g2 ma't' from the surface
(7) Distance glz is 0.5 to 1. It is about 0mm. Note that the illustrated first and second grooves 210°220.31
The bottom portions g1 and g2 of 0, 320, and 330 are linearly inclined from the front surface of the core block material 10 toward the end surface of the core block material 10;
is a concave radius 2 with respect to the front surface of the core block material 10
It may be an arc of about 0 mm. For example, as shown in FIG. 4-C, erase core material 30 on the front surface of core block material 10 and intermediate core material 4
Form an arc-shaped groove (position indicated by dotted line g3 in Figure 4-C) with a circular grindstone to a predetermined depth from the butt surface with 0, then move the grindstone parallel to the front surface with the arrow P
The groove may be continuously moved in the direction indicated by the dotted line g3' in FIG. 4-C to form the bottom g2 of the predetermined groove. Note that, unlike the formation of the first groove and the second groove described above, from the front surface of the intermediate core material 40. A first groove may be provided in the track direction to the end surface of the core block material on the read/write core side, and a second groove may be provided in the track direction from the front surface of the intermediate core material 40 to the end surface of the core block material on the erase core side. In this case, the track widths of the read/write gap and erase gap have already been determined by forming the first and second grooves, and both gaps exist on the front surface side, so the front surface grinding described later is not necessarily necessary. Not necessary. In addition, in the above, the starting end of one of the first and second grooves may be the front surface of the intermediate core material. Formation of such grooves can normally be performed by grinding with a whetstone or the like, which is extremely advantageous in terms of manufacturing. Grooves 210, 220° 310.32 formed in this way
0.330 is preferably filled with a non-magnetic filler 5 such as glass. Next, the core block material 10 is read/write gap 71
The front surface is then ground until an erase gap 75.degree. 76 appears on the front surface. That is, the bottom g1. of the groove in FIG. 4-B. The front surface is located between the intersection point of g2 and the intermediate core material 40 and the apex top n, and the predetermined gap depth is usually 0.
The front surface of the core block material 10 is ground until a thickness of 0.02 to 0.05 mm is formed. FIG. 7 shows an example in which the front surface is ground to the intersection of the groove bottoms g1 and g2. As shown in FIG. 7, the core block 1 has an inclined groove extending from the front surface of the intermediate core 4 to the end surface in the track direction of the core block on the read/write side.
10 and 220, and inclined grooves extending from the front surface of the intermediate core 4 to the end surface in the track direction of the core block on the erase side are formed as second grooves 310, 320, and 330. The track of the gap is determined by these grooves as described above. The read/write side core portion 25 of the core block 1 in which the grooves are formed has a winding 9 for the read/write head.
1 again. The erase side core portions 35 each have a winding 95 for the erase head. The number of turns of the winding 91 is usually about 100 to 300 turns x 2. The number of turns in one winding 95 is usually 20-1.
It is assumed to be about 00 turns. Note that FIGS. 5 to 7 show an example where the distance a in the track width direction between the first groove 210 and the groove 220 is equal to the width of the second groove 330. The size of b may be within the above range, and a<b as shown in FIG.
or a>b as shown in FIG. Further, in the present invention, two second grooves are provided for determining the widths of the erase gaps 75 and 76, but they may be formed only at one location on the front surface of the core block l. That is, as shown in FIG.
A groove 340 is formed approximately in the center of the front surface of the groove 340.
The track width of the erase gap may be regulated by the track width direction and both end surfaces of the core block l in the track width direction. In this case, the width of the groove 340 in the track width direction may be within the same range as the groove 330 described above, and may be appropriately determined from the relationship with the width of the read/write gear 71. Furthermore, in the present invention, as shown in FIG. 11, a long core block material 10 that is elongated in the track width direction is prepared, and the first core block material 10 is used to determine the width of the read/write gap 71 described above. a second groove 310. for determining the width of grooves 210, 220 and erase gaps 75, 76;
It is preferable to form two or more sets of magnetic heads 320 and 330, and then cut them into unit blocks and grind and polish them to form individual magnetic heads. In this case, the first and second grooves may be filled with the non-magnetic filler either before or after cutting each unit block. By such a method, it becomes possible to easily manufacture a large quantity of magnetic heads with high precision and stable quality. Further, in the present invention, as shown in FIG.
The track of the second groove 330 is smaller than the distance a between the first grooves 210 and 220 in Figure A.

[1] Direction 1] When b is small, the wall 410 is formed on the front surface of the core block material 10 by the first grooves 210, 220 and the second grooves 330.
．． 420 is formed. The thickness of the walls 410 and 420 in the track width direction is extremely thin, about 0.001 to 0.01 mm. Therefore, when grinding the front surface of the core block material 10 described above, the walls 410 and 420 may be damaged.
Undesirable. Therefore, as shown in FIG. 13, an intermediate core notch 430 may be formed in advance approximately at the center of the intermediate core material 40 in the track direction so as to reach both outer sides in the track 111 direction. In this case, the length of the intermediate core notch 430 in the track direction is approximately 0.1 to 0.5 mm, and the length of the intermediate core notch 430 is approximately 0.1 to 0.5 mm.
The length of the 30 core block material 10 in the direction perpendicular to the front surface is about 0.1 to 0.3 mm. In the magnetic head of the present invention, as shown in FIG. 14, the read/write core 2 and the read/write intermediate core 45 are integrated, and the erase core material 3 and the erase intermediate core 46 are integrated.
A core block material 10 may be used in which an intermediate core is formed from two cores by integrating them with an insulating layer 6 interposed therebetween. In addition, as shown in FIG. 15, the read/write core material 2
0 and the intermediate core material 40, and an erase back core portion 39 may be provided between the erase core material 30 and the intermediate core material 40. It may also be applied to the back core section 29 and the erase back core section 39. Further, unlike the above, there may be only one erase gap and one second groove. Furthermore, sliders 15 and 16 are bonded so as to sandwich both side surfaces of the integrated core block consisting of the read/write core 2, intermediate core 4, and erase core 3. The sliders 15 and 16 are provided for fixing and reinforcing the integrated body of the core block. The materials used for the slides F-15 and F-16 include nonmagnetic ceramics such as barium titanate, potassium titanate, calcium titanate, and strontium titanate. Various slider shapes are possible.
In the illustrated example, a notch is provided to accommodate the read/write head winding 91 and the erase head winding 95. A notch for inserting a core block may be provided, and the core block l may be inserted and fixed into this notch. In addition, in the illustrated example, a groove 160 for ensuring running stability of the magnetic recording medium is provided on the sliding surface of the track 1.
It is formed to run perpendicular to the 11th direction. The groove 160 has a depth of about 0.2 to 1.0 mm and a width of about 0.2 to 1.5 mm. Using such a magnetic head, it is possible to create a so-called gimbal-type magnetic head and a so-called button-type, T-type, or other fixed type magnetic head. Such a magnetic head of the present invention can effectively exhibit its excellent characteristics as a floppy head. ■Specific effects of the invention The magnetic head of the present invention has a read/write gap and an erase gap formed by forming grooves in the track direction on the front surface of a core block that integrates a read/write core, an intermediate core, and an erase core. It is. Therefore, it has become possible to create a highly accurate magnetic head that is free from variations in the position, size, etc. of read/write gaps and erase gaps that occur during the assembly of conventional magnetic heads. In addition, the time required to obtain positional accuracy during one assembly can be significantly shortened, the number of steps can be reduced, and manufacturing costs can be reduced.

[Brief explanation of drawings]

1 and 2 are views showing one embodiment of the magnetic head of the present invention, of which FIG. 1 is a perspective view and FIG. 2 is a plan view. FIG. 3 is a perspective view of a core block material used in the magnetic head of the present invention. Figures 4-A, 4-B, and 4-C are diagrams showing the positions of grooves when grooves are provided in the core block material shown in Figure 3, of which Figure 4-A is a plan view. 4-B and 4-C are front views. FIG. 5 is a perspective view of the core block material shown in FIG. 3 with grooves formed therein. 6-A, 6-B, and 6-C are a plan view, a front view, and a side view of the core block material shown in FIG. 5, respectively. 7, 8, 9 and 10. FIG. 3 is a perspective view showing an example of a core block used in the magnetic head of the present invention. Figures 11, 12, 13, 14 and 15
The figures are perspective views showing examples of core block materials used in the magnetic head of the present invention. 16 and 17 are diagrams showing a conventional magnetic head, of which FIG. 16 is a perspective view and FIG. 17 is a plan view. Explanation of symbols l: Core block. 10... Core block material. 2... Read/write core, 20... Read/write core material, 21... Read/write front core part, 25... Read/write side core part, 29... Read/write back core part, 210.220 . . . first groove, 3. erase core, 30. erase core material, 31.. erase front core section, 35.. erase side core section, 39.. erase back core section, 310. 320, 330, 340... second groove, 4.
...Intermediate core, 40...Intermediate core material. 410.420...Wall, 430...Intermediate core notch, 45...Read/write intermediate core, 46...Erase intermediate core, 5...Nonmagnetic filler, 6...Insulating layer , 71... Read/write gap, 75.76... Erase gap, 81.82, 85, 86.87... Non-magnetic material filling part. 91.95...Winding wire, 15.16...Slider, 120.130...Apex section, 160...Slider part groove Applicant TDC Co., Ltd.-4-12, 1 FfG, 1 FIG, 3 FIG, 4-A 7′ FIG, 4-C =
L Mu U-N

Claims (16)

[Claims] (1) It has a core block in which a read/write core, an intermediate core, and an erase core are integrated, and a first The track width of the read/write gap on the abutting surface of the read/write core and the intermediate core is regulated by the groove, and in the track direction of the front surface of the core block, from the front surface of the intermediate core to the erase core side. 1. A magnetic head comprising a second groove extending to an end face of the core block, the groove regulating a track width of an erase gap on an abutting surface between an intermediate core and an erase core. (2) The magnetic head according to claim 1, wherein the first grooves are provided on both outer sides of the front surface in the track width direction. (3) The second groove is provided at approximately the center of the front surface in the track width direction, and erase gaps are provided on both outer sides of the second groove in the track width direction.
The magnetic head described in section. (4) A second groove is provided on the front surface at approximately the center in the track width direction and on both outer sides in the track width direction, and an erase gap is provided on both outer sides in the track width direction of the central second groove. A magnetic head according to claim 2. (5) The magnetic head according to any one of claims 1 to 4, wherein the first and second grooves are continuously deepened from the front surface of the intermediate core toward the end surface of the core block. (6) A magnetic head according to any one of claims 1 to 5, wherein the first and second grooves are filled with a non-magnetic filler. (7) Track the first groove on the front surface of the core block material that integrates the read/write core material, intermediate core material, and erase core material from the front surface of the erase core or intermediate core to the end surface of the core block material on the read/write core side. A second groove is provided in the track direction from the front surface of the read/write core or intermediate core to the end surface of the core block material on the erase core side, and then the front surface of this core block material is polished, and the first groove A method of manufacturing a magnetic head, comprising obtaining a core block in which the track width of a write gap is regulated and the track width of an erase gap is regulated by a second groove. (8) The method for manufacturing a magnetic head according to claim 7, wherein the front surface side is ground during polishing. (9) The method of manufacturing a magnetic head according to claim 7 or 8, wherein the front surface of the core block material is polished while the first and second grooves are filled with a non-magnetic filler. (10) A magnetic head manufacturing method according to any one of claims 7 to 9, in which the first grooves are provided on both outer sides in the track width direction of the front surface. (11) The magnetic field according to claim 10, wherein the second groove is provided at approximately the center of the front surface in the track width direction, and erase gaps are formed on both outer sides of the second groove in the track width direction. Head manufacturing method. (12) A second groove is provided at approximately the center of the front surface in the track width direction and on both outer sides in the track width direction, and a second groove is provided in the center.
11. The method of manufacturing a magnetic head according to claim 10, wherein erase gaps are formed on both outer sides of the groove in the track width direction. (13) The magnetic head according to claims 7 to 12, wherein the first and second grooves are formed so as to become continuously deeper from the front surface of the core block material toward the end surface of the core block material. manufacturing method. (14) A plurality of first and second grooves are provided in the core block material, and the core block material is polished or ground/polished after being cut into predetermined units of the core block material, claim 7. , Sections 8 and 10 to 13
A method for manufacturing a magnetic head according to any one of Items 1 and 2. (15) Claim 14, in which the core block material is cut with the first and second grooves filled with a non-magnetic filler.
The method for manufacturing the magnetic head described in section 1. (16) The method of manufacturing a magnetic head according to claim 14, wherein the core block material is cut without filling the first and second grooves with the nonmagnetic filler, and then the nonmagnetic filler is filled.