KR900000627B1 - Complex type magnetic head and method of its producing - Google Patents

Abstract

A composite magnetic head has two 'C' cores (32,42) of magnetic material to which are bounded 'I' core plates using a non magnetic material, e.g. glass or silicon dioxide. The top edges of both formed 'CI' blocks are machined to form record (35) playback and erase (45) grooves. The two blocks are joined together to form a signle unit (50) and the record and erase grooves are filled with a non magentic material at the interface between the two blocks. There is a channel section that is also filled with a bonding material (54) to provide increased machanical strength. The complete assembly is cut into sections (c) to form individual units. Windings are located in the channel sections (36).

Description

Hybrid magnetic head and its manufacturing method

1A is a perspective view of a completed state showing an embodiment of a hybrid magnetic head according to the present invention.

1B is a perspective view of a state in which a slider is bonded.

2a to 2i are perspective views showing the manufacturing process of the composite magnetic head according to the present invention.

3 is a plan view of a conventional hybrid magnetic head.

4 is a front view.

* Explanation of symbols for main parts of the drawings

30: recording and playback side magnetic core block 30A: recording and playback side magnetic core

31: I block (half core block) 32: C block (half core block)

33: magnetic gap 33A: recording and playback gap

34, 36: winding groove 37: coil holding

38: coil 40: erased magnetic core block

40A: erased magnetic core 41: I block (half core block)

42: C block (half core block) 43: branch gap

43A: erase gap 44, 46: winding groove

47: coil holding 48: coil

The present invention relates to a composite magnetic head capable of high density recording and reproduction. In a recording method in which a recording track is formed along the circumferential direction of a disc-shaped magnetic recording medium such as a magnetic disk, if the track interval is narrowed to increase the recording density, a cross feed in which adjacent recording tracks overlap at the time of recording, and Leakage flux called crosstalk from the recording track is likely to occur. In order to solve this crosstalk problem, conventionally, a hybrid magnetic head as shown in FIGS. 3 and 4 has been proposed. This hybrid magnetic head is substantially free of signals on both sides of the recording track Tw by scanning the weak side in the width direction of the recording track Tw recorded by the recording / reproducing gap 10 by the one-phase erasing head 20. It has a basic function of forming a guard band Te. In this manner, by guarding the guard band Te on both sides of the recording track Tw, even if the track interval is narrowed, no crossfeed or crosstalk between adjacent tracks occurs.

This conventional hybrid magnetic head is formed by coupling a non-magnetic layer 29 such as ceramics or glass with the recording / reproducing side magnetic core 11 and the erasing side magnetic core 21 interposed therebetween. The recording / reproducing side magnetic core 11 and the erasing side magnetic core 21 are formed by combining the I-shaped half cores 12 and 22 and the C-shaped half cores 13 and 33, respectively. A gap between them forms the recording / playback gap 10 and the erase gap 20, respectively. In the recording / reproducing gap 10 and the erasing gap 20, nonmagnetic materials 14 and 24, such as high melting point glass, are interposed. On both sides of the recording / reproducing gap 10 in the width direction, notches 15 are formed between the half cores 12 and 13. This cutout groove 15 regulates the track width Tw, and is filled with a nonmagnetic material (generally glass) 16 therein.

In addition, the cutout groove 25 having a width Ew that extends between the half cores 22 and 23 is formed at the center portion in the width direction of the erase gap 20. This cutout groove 25 regulates the erase track width Te, and is filled with a nonmagnetic material 26 in the same manner. The width Ew of the notch 25 is set substantially equal to or smaller than the recording track width Tw. In addition, the length Gl in the track direction of the cutout groove 25 is usually set to 20 times or more of the gap gap of the erasing gap 20 in order to enable reliable erasure. Coils 17 and 27 are wound around C-shaped half cores 13 and 23 of the recording / reproducing side magnetic core 11 and the erasing side early core 21, respectively.

However, since this notch groove 15 and notch groove 25 are through grooves which are machined over the entire length of the recording / reproducing side magnetic core 11 and the erasing side magnetic core 21, The cross-sectional areas of both magnetic cores 11 and 21, that is, the magnetic paths become narrow, increase the magnetoresistance and deteriorate the recording and reproducing efficiency. This problem becomes more remarkable as the magnetic head is miniaturized in order to enable high density recording, and at the same time, not only the magnetic problem but also the problem that the mechanical strength of the transfer magnetic cores 11 and 21 falls. In order to increase the recording density of the rotating recording medium, it is preferable to reduce the interval 1 between the recording / reproducing gap 10 and the erasing gap 20 as much as possible. However, in the conventional structure, the half-core 12 and the half-core 22 Since it is necessary to form notch grooves 15 and 16 penetrating through), it is necessary to have a thickness of a predetermined value or more, and thus it was difficult to reduce this gap 1.

In the conventional manufacturing process of the hybrid magnetic head, on the other hand, the half cores 12 and 13 of the recording / reproducing side magnetic core 11 and the half cores 22 and 23 of the erasing side magnetic core 21 are used. Are each formed in the shape of blocks as shown by the dashed lines in FIG. 3, which are later cut and formed. However, the notch grooves 15 and the notch grooves 25 formed in the half cores 12, 13, and the half cores 22, 23 are respectively half cores 12, It is necessary to form before (13) and the half cores 22 and 23 before joining, and to join them after that. However, after the notch 15 and the notch 25 are formed in this way, when the half cores 12, 13, and the half cores 22, 23 are joined, there is a possibility that the groove position is shifted at the time of joining. . It is clear that this home positioning cannot break high-density records without precision, and this home positioning deteriorates workability, complicates the machining process, worsens yield, and increases production price.

The present invention increases the cross-sectional area of the magnetic core and increases the mechanical strength and narrows the gap between the recording / reproducing gap and the erasing gap, based on the above problems with the conventional hybrid branch head. It is an object of the present invention to obtain a complex magnetic head which is easily available.

The hybrid magnetic head of the present invention has been made based on the finding that the problem of the conventional product is that the cutout grooves that regulate the recording track width and the erasing track width are through holes over the entire length of the magnetic core. At least one of the cutout grooves formed in the core and the magnetic core for erasing is formed as a user cutout groove having a low wall in the core. In the method of the present invention, a pair of half core blocks are joined to form a magnetic core block for recording and reproducing and an erasing magnetic core block, respectively, and then a user cutout groove is formed between the pair of half core blocks to be joined. The recording and reproducing magnetic core block and the erasing magnetic core block are bonded to each other by aligning the user notch grooves, and the non-magnetic material is filled into the user notch grooves of the junction block and cut at predetermined intervals. Hereinafter, the present invention will be described based on the illustrated embodiments.

2a to i are process drawings of the manufacturing method according to the present invention. The pair of half core blocks constituting the magnetic core blocks on the recording / reproducing side and the erasing side has a cross section having flat I blocks 31 and 41 and depth regulating grooves 34 and 44 of the magnetic gap. It consists of C blocks 32 and 42 substantially C-shaped. In the present invention, as shown in Figs. (A) and (b), first, I blocks 31, 41, C blocks 32, and 42 are joined, respectively, and the magnetic core block on the recording / reproducing side (hereinafter, recording and reproducing) is used. Side block) 30 and an erase side magnetic core block (hereinafter referred to as an erase side block) 40. Each of these blocks is formed by depositing or sputtering an adhesive layer made of a non-magnetic material such as, for example, high melting point glass or SiO2 on at least one of the polished bonding surfaces, respectively, and the gap between the junctions is defined by magnetic gaps 33 and 43. Becomes The magnetic gap depth regulating winding grooves 34 and 44 of the C blocks 32 and 42 are open to the I block 31 and 41 sides. The I blocks 31, 41, and C blocks 32, 42 are made of, for example, single crystal ferrite Mn-Zn ferrite, Fe-Si alloy or the like.

After the recording / reproducing side block 30 and the erasing side block 40 are formed in this way, the recording / reproducing side user cut-out groove 35 and the erasing side user are formed in each block as shown in FIG. The notch grooves 45 are formed at predetermined intervals. The recording / reproducing side user cutout groove 35 and the erasing side user cutout groove 45 are magnetic gaps 33. It is formed over the I block 31 and the C block 42, and the I block 41 and the C block 42 so as to have a positional relationship orthogonal to (43). In the erase-side magnetic core block 40, cutting guide grooves 49 are formed between the erase-side user cut grooves 45 adjacent to each other again. This cutting guide groove 49 corresponds to each recording / playing-side user cut-out groove 35 of the recording-reproducing-side magnetic core block 30 and is one erased-side user cut-out groove between adjacent recording / playing-side user cut-out grooves 35. The position and spacing of each groove are set so that 45 is located.

The recording / reproducing side user cutout groove 35 and the erasing side user cutout groove 45 are formed on the entire surface of the I blocks 31 and 41, respectively, and at the same time, the C blocks 32 and 42 are formed. It is formed into the inclined groove which deepens from the side to the I block 31, 41 side, and the end surface of I block 31, 41 side is opened. The recording and playback side user cutout groove 35 and the erasing side user cutout groove 45 communicate with a portion of the bottom wall of the magnetic gap depth regulating winding grooves 34 and 44, but the grooves 35 and 45 are thus connected. The part of the bottom wall of the stool also includes the concept of the user in the present invention. Importantly, a groove formed in a form in which a bottom wall is provided in the core without penetrating through the entire length of the recording / reproducing side block 30 and the erasing side block 40 with respect to the conventional through groove is called a user in the present invention.

In this manner, the recording / reproducing side block 30 and the erasing-side block 40 which have finished the processing of the recording / reproducing side user cutout groove 35 and the erasing side user cutout groove 45 are then placed in block I as shown in the drawing (d). (31) and (41) are joined to form a joining block (50). At this time, the cutting guide groove 49 is positioned at the center of the recording / reproducing side user cut-out groove 35, and the bonding surface is provided with a spacer 51 for blocking the recording / reproducing magnetic circuit and the erasing magnetic circuit. The spacer 51 is made of an adhesive glass interposed on the bonding surface when bonding the recording / reproducing side block 30 and the erasing side block 40, as in the conventional product, or a spacer provided separately from the I block ( It is comprised by joining both blocks after interposing between 31) and (41).

When the joining of the recording / reproducing side block 30 and the erasing side block 40 is completed, the recording / reproducing side user section on the surface of the recording / reproducing side block 30 and the erasing side block 40 as shown in FIG. A nonmagnetic material 52 such as glass in a molten softened state is filled around the grain groove 35 and the portion of the erasing-side user cut groove 45. The nonmagnetic material 52 is filled in the recording / reproducing side user cutout groove 35 and the erasing side user cutout groove 45 and also flows into the magnetic gap depth regulating winding grooves 34 and 44 by the fluidity thereof. The bonding strength between the recording / reproducing side block 30 and the erasing side block 40 is increased. The bonding block 50 filled with the nonmagnetic material 52 polishes the magnetic recording medium and the contact surface as shown in FIG.

After the above processing is completed again, the joining block 50 is subjected to post-processing of the winding grooves 36, 46 and the joint reinforcing grooves 53 as shown in the same drawing (g). The joint reinforcing groove 53 is formed over the I block 31 of the recording / reproducing side block 30 and the I block 41 of the erasing side block 40, and is formed by opening the rear surface thereof. As shown in (h), the connecting material 54 made of a nonmagnetic material such as glass is filled. This connecting material 54 is effective for increasing the bonding strength between the recording / reproducing side block 30 and the erasing side block 40, and is effective for more reliably cutting off the recording / reproducing magnetic circuit and the erasing magnetic circuit.

Winding groove 36. Reference numeral 46 denotes the C block 32 of the recording / reproducing side block 30 and the C block 42 of the erasing side block 40 on the opposite side of the magnetic gaps 33 and 43, respectively. Open. The winding grooves 36 and 46 are formed in the C blocks 32 and 42 so as not to reach the joint surfaces of the I blocks 31 and 41 so that the distance K between them is as large as possible. .

When the connection material 54 is filled as mentioned above, the process as the junction block 50 is complete | finished, and this is cut | disconnected along the cutting line C shown by the dashed line in the same figure (h). The cutting line C is set at the center of the width direction of the cutting guide groove 49, that is, the recording / reproducing side user cutting groove 35, and the cut composite magnetic core chip 60 is as shown in FIG. On the recording / reproducing side block 30, the recording / reproducing side user cutout grooves 35 (non-magnetic material 52) are located on both sides of the central magnetic gap 33, and on the erasing-side block 40 side, the central erasing-side user section is placed. The magnetic gap 43 is located on both sides of the grain recess 45 (nonmagnetic material 52).

The composite magnetic core chip 60 thus formed is cut into coil struts 37 and 47 formed by the winding grooves 36 and 46 as shown in FIG. 1A. 48) and the back bar 55 is bonded to the rear side or rear end surface of the composite magnetic core chip 60 to complete.

The back bar 55 is formed by integrating a non-magnetic material 58, such as glass, between the recording / reproducing side back bar 56 made of magnetic material and the erasing side back bar 57, thereby strengthening the bonding with the non-magnetic material 58. The groove 53 is aligned and bonded to the rear side surface of the hybrid magnetic core chip 60. Joining can be performed using well-known joining materials, such as glass and resin. The recording / reproducing side back bar 56 and the erasing side back bar 57 close the data on the recording / reproducing side and the erasing side, respectively. When the nonmagnetic material 58 is integrated in this manner, the joining becomes easy. If the length of one of the nonmagnetic material 58 and the joining reinforcement groove 53 is made larger than the other, the allowable value of position shift in the longitudinal direction of the back bar 55 can be increased, and the joining operation becomes easy.

Further, by setting the distance k between the winding grooves 36 and 46 to be large, the length (area) of the abutting surface of the back bar 55 is increased. For this reason, the back bar 55 can be easily joined and the magnetic resistance on the opposite side to the magnetic gaps 33 and 43 including the back bar 55 can be reduced.

FIG. 1A shows the hybrid magnetic head in the completed state with the back bar 55 removed, and the cut recording / reproducing side magnetic core block 30 constitutes the recording / reproducing side magnetic core 30A, and the erase-side magnetic core block 40 is shown. ) Constitutes the erasing-side magnetic core 40A. The magnetic gap 33 constitutes the recording / reproducing gap 33A, and the magnetic gap 43 constitutes the erasing gap 43A. Other parts are indicated by symbols used in the description of the manufacturing process. FIG. 1B shows a state in which the composite magnetic head is joined to the slider 59.

In the above embodiment, the recording / reproducing side user notch groove 35 and the erasing side dielectric notch groove 45 are formed as inclined grooves, so that the notch groove is easily formed by the cutting machine and both user notch grooves 35 are formed. 45 is shorter as it goes inside the core, and it is effective to keep the path of the recording / reproducing side block 30 and the erasing side block 40 wide. However, the same effect can be expected with the V-shaped groove and the U-shaped groove, for example. In the present invention, the bottom shape of the recording / reproducing side user cutout groove 35 and the erasing side user cutout groove 45 is irrelevant. It is satisfied that the user is not penetrated over the entire length of the hybrid magnetic core, but has a bottom surface in the core, and the composite is larger than the conventional product, thereby increasing the cross-sectional area of the magnetic core chip 60 to increase the magnetic path and increase the mechanical strength. It will increase the effect.

According to the present invention, the interval 1 (FIG. 1) between the recording / reproducing side user cutout 33 and the erasing magnetic gap 43 can be made smaller than that of the conventional apparatus. This is an effect of opening the recording / reproducing side block 30 and the erasing side block 40 to the joint surface side in addition to the recording / reproducing side user notch 35 and the erasing side of the user notch 45 as a user groove. . That is, since the recording / reproducing side user cutout groove 35 and the erasing side user cutout groove 45 do not penetrate and open to the joining surface side, the recording / reproducing side user cutout groove 35 and the erasing side user cutout groove 45 Decreases in strength of the composite magnetic core chip 60 by this. Thus, the gap 1 can be made small and a higher density recording is possible. In the above embodiment, both the recording / reproduction side user cutout groove 35 and the erasing side user cutout groove 45 on the erase side block 40 side are used as users, but only one user can obtain a certain effect.

As described above, the composite magnetic head according to the present invention can increase the cross-sectional area of the magnetic core and increase the mechanical strength by increasing the cross-sectional area of the magnetic core by using the notch grooves for regulating the recording / reproducing track width and the erasing track width. It is also effective to increase the recording density by shortening the distance between the recording / playback gap and the erase gap. In the method of the present invention, the pair of blocks constituting the recording / reproducing side block and the erasing side block are first joined, and then, a user cutout groove is formed between the pair of the joined blocks. There is no room for it. Therefore, the groove positioning is not necessary, and the high precision composite magnetic head can be formed easily by a simple machining process.

Further, according to the present invention, a back bar constituting the magnetic closure circuit can be easily attached by closing the recording / reproducing side magnetic circuit and the erasing side magnetic circuit in the hybrid magnetic head, thereby making positioning easy. Therefore, the workability can be improved and the price can be lowered. In addition, since the tolerance for misalignment can be increased, the adverse effect on the magnetic circuit caused by misalignment of the backbar can be eliminated. According to the present invention, a joint reinforcing groove is formed between the two cores in the joint surface of the recording / reproducing side magnetic core and the erasing side magnetic core opposite to the side on which the magnetic recording medium travels, and the nonmagnetic material is formed in the joint reinforcing groove. Since the low alloying material was filled, the bonding strength between the recording / reproducing side magnetic core and the erasing side magnetic core can be increased.

In addition, since the hybrid magnetic head of the present invention is formed by post-processing on a half core bonded to the winding grooves formed in the magnetic cores on the recording / reproducing side and the erasing side, the winding reaches from the beginning to the joint surface of the half core on one side of the half core. The bond strength of the half core can be increased as compared with the conventional products forming the grooves. In addition, since the winding groove according to the present invention is formed at a position not reaching the joining surface of the half core, the magnetic resistance on the opposite side to the magnetic gap can be reduced, and the positioning fixation of the back bar is easy.

Claims (16)

A recording / playback magnetic core 30A having recording / playback gaps 33A and cutout grooves located on both sides of the recording / playback gap to restrict recording / playback track widths; A composite magnetic head formed by joining an erasing magnetic core 40A having a pair of erasing gaps located on both sides of the recording / reproducing track and a cutout groove for restricting the erasing track width by the erasing gap. At least one of the cutout grooves of the magnetic core (30A) and the erasing magnetic core (40A) is formed as a user cutout groove having a bottom wall in the core. 2. The hybrid magnetic head according to claim 1, wherein the user cutout groove has a long length on the side of the core surface in contact with the magnetic recording medium and shortens as it enters the core. 3. The user cutout groove of claim 2, wherein the user cutout groove has a length from the surface side of the recording and reproducing magnetic core to the erasing magnetic core to the joint surface of both cores, and the bottom wall is formed into the deep inclined groove of the joint surface side. Hybrid magnetic head, characterized in that. A user section for joining a half-core block of one phase whose junction surface becomes a magnetic gap to form a magnetic core block for recording and reproducing and a magnetic core block for erasing, respectively, and then restricting the recording track width to the magnetic core block for recording and reproducing. The grooves are overlapped between the pair of half core blocks bonded to each other, and formed at predetermined intervals, and the predetermined grooves are interposed between the pair of half core blocks in which the user notch grooves for restricting the erase track width are bonded to the erase magnetic core block. Then, the recording and reproducing magnetic core block and the erasing magnetic core block are joined to each other by positioning the user cutout grooves, and the user cutouts of the junction block are filled with a nonmagnetic material, and then a predetermined interval is formed. Method for producing a composite magnetic head, characterized in that for cutting. 5. The manufacturing method of a hybrid magnetic head as claimed in claim 4, wherein the respective user cutout grooves of the recording and reproducing magnetic core block and the erasing magnetic core block are open at the joint surface side of both blocks. 6. The pair of half core blocks constituting the recording / reproducing magnetic core block and the erasing magnetic core block each have one block of flat plate shape, and the other side of this I block side is open. A method of manufacturing a composite magnetic head, characterized in that the C-shaped C block has a cross section having a restricting groove of a magnetic gap depth. 7. The method of manufacturing a composite magnetic head according to claim 6, wherein the bottom of the user cutout groove is inclined from the C block side toward the I block side. 5. The joint block of the recording / reproducing side magnetic core block and the erasing side magnetic core block is further subjected to post-processing joint reinforcing grooves covering both core blocks at the junction opposite to the magnetic gap and made of nonmagnetic material. A method for producing a composite magnetic head, wherein the connection material is filled. The joint block of the recording / reproducing side magnetic core block and the erasing side magnetic core block is post-processed after winding grooves having cross sections opposite to the magnetic gap in each core block. A method of manufacturing a composite magnetic head, characterized in that the wound. A pair of magnetic noses constituting the recording and reproducing gap 33A, a back bar 55 disposed on the rear of the pair of magnetic cores to form a closed magnetic circuit of the pair of magnetic cores, and located at both sides of the recording and reproducing gap. A recording / reproducing magnetic core having a notch groove for restricting the recording / reproducing track width; A pair of magnetic cores forming a pair of erasing gaps located on both sides of the recording / reproducing track, a back bar disposed on the rear surface of the pair of magnetic cores, and constituting the pair of magnetic cores and a closed magnetic circuit; A hybrid magnetic head formed by joining an erasing magnetic core having a notch groove for regulating an erase track width, wherein a nonmagnetic material is interposed between the back bar 56 on the reproduction side and the back bar 57 on the erase side. Wherein the integrated backbar is formed by joining the nonmagnetic material to both core assemblies in accordance with the joint surface positions of the recording and reproducing magnetic core and the erasing magnetic core. The joint reinforcing groove between the two cores is formed in the joining surface of the recording material new magnetic core and the erasing magnetic core positioned in the nonmagnetic material portion of the integrated backbar, and the joining material is formed in the joining reinforcing groove. Hybrid magnetic head, characterized in that the charge. 11. The hybrid magnetic head according to claim 10, wherein the width of the nonmagnetic material of the integrated back bar is set smaller than the width of the reinforcing groove of the joining core. A recording and reproducing magnetic core 30A having a recording and reproducing gap 33A and cutout grooves positioned at both sides of the recording and reproducing gap to restrict the recording and reproducing track width; A magnetic recording medium comprising a magnetic magnetic core 40A formed by joining an erasing magnetic core 40A having a pair of erasing gaps located on both sides of the recording / reproducing track, and a cutout groove for regulating the width of the erasing track by the erasing gap. A joint reinforcing groove 53 is formed in the joint surface of the two cores on the opposite side to the traveling side of the core between the two cores, and the joint reinforcing groove is filled with a joint material made of a nonmagnetic material. Type magnetic head. The recording / reproducing side magnetic core and the erasing-side magnetic core are provided with a back bar for closing the magnetic circuit on the back side of the recording / reproducing gap and the erasing gap, respectively, and the two back bars are nonmagnetic interposed therebetween. A hybrid magnetic head characterized in that it is previously matched through a material. A pair of core blocks whose junction surfaces are magnetic gaps are joined to form a recording / reproduction magnetic core block 30 and an erasing magnetic core block 40, respectively. The recording / reproducing magnetic core block and the erasing magnetic core are respectively formed. In a hybrid magnetic head formed by joining blocks, the magnetic gap block opposite to the magnetic gap is located at a position which does not reach the junction surface of the half block constituting each magnetic core block of the magnetic core block for recording and reproducing. Hybrid magnetic head, characterized in that each formed in the winding groove. 16. The pair of core blocks constituting the recording and reproducing magnetic core block and the erasing magnetic core block each have a depth of a magnetic gap in which one I-plate side is open and the other I-block side is open. A cross section having a restricting groove is a C block having a substantially C shape, and a winding groove is formed in the C block.

Images