JP2916746B2 - Mirror polishing method of surface facing gap in magnetic head and surface grinder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for mirror-polishing a surface facing a gap in a magnetic head and a surface grinder used directly in this method, and more particularly to a method for polishing a surface facing a gap in a magnetic head for a VTR (video tape recorder). It is suitable for mirror polishing.

[0002]

2. Description of the Related Art In general, manufacturing a magnetic head for a VTR usually includes the following steps. FIG.
Is for explaining this step. As shown in FIG. 5A, a V-shaped groove 2 for regulating the track width is provided in the core block 1, and the glass 3 is poured into the groove 2 and solidified. (Glass mold). The core block 4 configured as described above and a core block 5 configured substantially in the same manner as the block 4 are butted as shown in FIG. 2B via a gap material made of glass (not shown). The core blocks 4 and 5 are welded and fixed to each other with the glass 3 and the glass serving as the gap material by heating in a state.
In the drawing, a groove 7 serving as a winding window 6 is provided only in the core block 4.

The block 8 fixed by welding is sliced as shown by a two-dot chain line after finishing the surface 9 to be the magnetic tape contact surface. And
By applying a winding to the winding window 6, a plurality of magnetic heads can be obtained. By the way, the gap opposing surface 10, which is the butting surface when the core blocks 4 and 5 are butted,
Mirror polishing is performed by a lapping machine through three steps of roughing, medium finishing, and final finishing. However, since the polishing rate of the lapping machine is low, the working time is long, which is one of the factors for increasing the cost.

In order to shorten the polishing time, it is conceivable to use a horizontal surface grinder having a high polishing rate, but there are the following problems. That is, when the gap facing surface of the magnetic head is polished using a horizontal surface grinder, chipping, chipping, peeling, and the like are likely to occur when the mesh of the grindstone of the grinding machine is coarse. In order to avoid such chipping and the like, if a fine grindstone is used as the grindstone, the grindstone is markedly clogged and the grindstone must be dressed frequently. Therefore, the total operation time required for polishing the gap facing surface is not sufficiently reduced. For this reason, in the mirror polishing of the gap opposing surface in the conventional magnetic head, the chipping, chipping,
Even if peeling or the like occurs, in the roughing in which the chipping or the like can be removed in the next polishing step of the intermediate finishing, a horizontal surface grinding machine may be used, but the horizontal surface grinding is performed in the steps after the intermediate finishing. No board was used. By the way, in the polishing of the glass-molded core block, the glass is easily embedded in the grindstone, and in this state, chipping, chipping, peeling, and the like occur frequently.

On the other hand, in order to shorten the working time required for dressing the grindstone, an erasing head and a dressing tool for audio as an article to be polished are inserted and fixed into a polishing jig. There is known a polishing apparatus in which a tool is pressed against an outer peripheral surface of a rotating polishing grindstone (see Japanese Patent Application Laid-Open No. 62-162472). However, in this polishing apparatus, the erasing head is rounded, and the polishing apparatus cannot mirror-polish the gap facing surface of the magnetic head. In addition, this polishing apparatus is designed so that the overall height of the dressing tool after the abrasive grains are fixed matches the completed dimension of the article to be polished after polishing, and the dressing is performed by the dressing tool after the polishing of the article to be polished. It requires time only for dressing separately from processing, and the time required for polishing and dressing cannot be sufficiently reduced. Incidentally, in this case, since the dressing tool also functions as a stopper, the article to be polished is not excessively polished. However, since the dress material is diamond, the wear amount of the grindstone at the time of dressing increases.

Separately from the above-mentioned polishing apparatus, as a device for planarly polishing a workpiece, a transport plate having through holes for holding a semiconductor wafer as a workpiece, and a transport plate provided on both sides of the transport plate. There is also known a polishing apparatus which includes a pair of platens provided and having a polishing cloth fixed thereto, and an abrasive layer for dressing the polishing cloth is bonded to the carrier plate, and the dressing is performed simultaneously with the polishing. (See JP-A-61-90868). In this case, the time required for polishing and dressing can be sufficiently reduced. However, in this polishing apparatus, the thickness of the abrasive layer is set such that the sum of the thickness of the carrier plate and the thickness of the upper and lower abrasive layers is substantially equal to the thickness of the wafer. The abrasive layer must be worn by a polishing cloth to the same extent as the wafer. For this reason, when processing of the wafer is completed and the next wafer is to be processed, it is necessary to replace the abrasive layer as well. However, since the abrasive layer as the dress material is adhered to the carrier plate, it cannot be easily replaced, and the replacement takes time, resulting in a longer polishing process time.

[0007]

As described above, in the conventional method for polishing the mirror-facing surface of the gap facing surface of the magnetic head, the polishing processing time becomes long, and therefore the polishing cost cannot be sufficiently satisfied. . The present invention has been made in view of the above problems, and has as its object to provide a method for mirror-polishing a surface facing a gap in a magnetic head and a surface grinder used in the method, which can sufficiently shorten the polishing processing time.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems and achieve the above object, a method for mirror-polishing a gap-facing surface in a magnetic head according to the present invention is provided. A rough grinding, semi-finishing and final finishing process required for mirror polishing, the rough grinding and semi-finishing are performed in parallel with each other using a grindstone and a work-attached surface plate that rotate around different axes, respectively. Using a surface grinding machine that polishes the work by rotating the face plate and the grindstone while the work is fixed to the face plate, the core block in which glass is molded in a groove for track width regulation is used. As a work, in the method of mirror-polishing the gap-facing surface of the core block, in the step corresponding to at least semi-finishing, A dressing material in which the abrasion speed of the grindstone is approximately the same as that of the work and the height from the surface on which the work is fixed is substantially the same as that of the work is fixed to the mounting surface plate with wax. And polishing the work.

The surface grinding machine used in this method is provided with a grindstone and a work-attached face plate which are parallel to each other and rotate about different axes, respectively, and the work is fixed to the face plate. A surface grinder for polishing the work by rotating the grindstone and the work, the work pasting surface plate, a stage disposed on the surface side to which the work is fixed, having a surface on which a dress material is to be pasted; Means for varying the height of the stage from the surface on which the work is fixed.

[0010]

As described above, since the dress material is stuck to the work-attached face plate, the grindstone is dressed as the work is polished, thereby preventing clogging of the grindstone.
Therefore, the mirror facing surface of the gap in the magnetic head can be polished in a short time without causing chipping, chipping, peeling, and the like on the core block as the work. Since the dress material wears to the same extent as the work, the dressing is simultaneously performed with the grinding operation as described above by changing the dress material when polishing a new work.
Since this dress material is attached to the face plate with wax, it can be easily replaced. Further, as described above, by attaching the dress material to the stage and changing the height of the stage, it is not necessary to replace the dress material with a new one every time the workpiece is polished.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG. FIG. 1 schematically shows a horizontal surface grinding machine 11. As is well known, the horizontal surface grinding machine 11 includes a grindstone 14 that rotates around different axes 12 and 13 that are parallel to each other, and a work attaching surface plate 15. The work 16 is polished by rotating the face plate 15 and the grindstone 14 in a fixed state. FIG. 1A shows a state in which the grindstone 14 is separated from the work 16. However, in the polishing operation, the face plate 15 is moved so as to approach the grindstone 14. Thereby, the work 16 is polished by the set dimension. As shown in FIG. 1B, a large number of workpieces 16 are arranged in a ring shape near the outer periphery of the face plate 15, but in FIG. 1A, in order to avoid unnecessary complexity of the drawing, Only two works 16 are shown. Incidentally, the surface of the whetstone 14 acting as a whetstone is only the portion 17 close to the peripheral surface.

In the mirror polishing method for the gap facing surface in the manufacturing process of the magnetic head, in the rough, medium, and finishing steps required for the mirror polishing, the above-mentioned horizontal flat surface is used for polishing corresponding to roughing and medium finishing. Using a grinding machine 11,
The glass 3 is inserted into the groove 2 for regulating the track width described in FIG.
The core blocks 4 and 5 with the
The gap opposing surfaces 10 of the core blocks 4 and 5
Polish. At the time of this polishing, the abrasion speed of the whetstone 14 by polishing is approximately the same as that of the work 16 on the work-attached surface plate 15, and the abrasion speed of the work 16 is substantially the same as that of the work 16. A dress material 18 having a height is pasted with wax.

As described above, since the dress material 18 is attached to the work attaching face plate 15, the grinding stone 14 is dressed as the work 16 is polished.
Clogging is prevented. Accordingly, chipping, chipping, peeling, and the like do not occur on the core blocks 4 and 5 that are the work 16, and the time required for the mirror polishing process as compared with the conventional case of performing a medium finish using a lapping machine. Is shortened. When the work 16 is polished as described above and the next work is polished, the dress material 18 is also replaced with a new one. The dress material 18 is attached to a position indicated by a chain line 18a in FIG.
The contact time between the grinding wheel 8 and the grinding wheel 14 is increased, and a further dressing effect can be obtained with a small amount of dress material.

In the above embodiment, the dress material 18 is directly adhered to the surface of the face plate 15 to which the work 16 is adhered. By increasing the height, a dress material having a relatively low height can be used. In addition, a stage having a surface on which a dress material 18 is attached is provided on the face plate 15 on the side on which the work 16 is attached, and the height of this stage from the surface on which the work is attached is varied. By providing means and changing the height of this stage, the dress material 18 is not replaced with a new one every time the work 16 is polished, and the dressing is performed simultaneously with the polishing of the work 16 a plurality of times by the same dress material. You can do it.

FIG. 3A shows the work attaching face plate 15 provided with the above-mentioned stage 19, and a screw 20 is fixed to this stage 19 as shown in FIG. The screw 20 is screwed into a female screw portion 21 provided on the face plate 15. 22 indicates a lock nut. A dress material 18 is attached to the stage 19 with wax, and in this state, the
To adjust the height of the dress material 18 from the face plate 15 to the height of the work 16 fixed to the face plate 15. Then, the position of the stage 19 is fixed by the nut 22. By polishing the work 16 in this state,
In the same manner as described with reference to FIG.
Is dressed.

Since the dress material 18 is directly fixed to the work-attached surface plate 15 by wax as described above, or is fixed via the stage 19, the dress material 1 is fixed.
8 can be easily replaced. The dress material 18 has a mesh larger than that of the grindstone 14 (for example, a dress material mesh # 1000 for a grindstone mesh # 2000). The material of the dress material 18 is desirably green silicon carbide-based abrasive particles abbreviated as GC or white alumina-based abrasive particles abbreviated as WA. As for the polishing of the core blocks 4 and 5, the bonding degree of N to R is desirable.

[0017]

As described above, the method of mirror polishing of the gap opposing surface in the magnetic head according to the present invention includes the steps of roughing, semi-finishing and final finishing during the roughing and semi-finishing. Using a surface grinder, dressing material is pasted on a work-attached face plate at least in polishing corresponding to medium finishing. As a result, the polishing speed is faster, the working time is greatly reduced, and there is no clogging as compared with the conventional case of using a lapping machine for medium finishing, so that chipping, chipping, peeling, etc. occur. Nor. In the present invention, the dress material is attached to the face plate with wax, so that the dress material can be easily replaced. Incidentally, a horizontal surface grinder having an electrolytic polishing function for dressing a grindstone simultaneously with polishing is also known, but an electrolytic polishing unit used for this is very expensive. Further, in the surface grinding machine of the present invention, since the surface on which the dress material is fixed is variable in height with respect to the surface on which the work is fixed, the same dress material is used and the work is polished a plurality of times. Dressing can be done.

[Brief description of the drawings]

FIG. 1 is a schematic view of a horizontal surface grinder for explaining an embodiment of the present invention, in which (a) is a partially sectional front view, and (b) is a right side view of the above (a). FIG.

FIG. 2 is a schematic perspective view for explaining a generally known manufacturing process of a magnetic head.

FIG. 3 is a schematic sectional view (a) of a main part of a horizontal surface grinder and a perspective view (b) of a jig used for the surface grinder for explaining another embodiment of the present invention.

[Explanation of symbols]

 2 Groove 3 Glass 4,5 Core block 10 Gap facing surface 11 Horizontal surface grinder 12,13 Axis 14 Grinding stone 15 Work sticking surface plate 16 Work 18 Dress material 19 Stage 20 Screw 21 Female screw part 22 Nut

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁶ , DB name) B24B 7/04 B24B 53/02 G11B 5/127

Claims (2)

(57) [Claims] 1. A method for mirror-polishing a gap-facing surface in a magnetic head manufacturing process, wherein, among roughing, semi-finishing, and final finishing steps required for mirror-polishing, roughing and semi-finishing are parallel to each other. Using a surface grinder that rotates the face plate and the grindstone while the work is fixed to the face plate and grinds the work with a grindstone and a work pasting surface plate that respectively rotate around different axes. In a method in which a core block in which glass is molded in a track width regulating groove is used as the work, and the gap opposing surface of the core block is mirror-polished, The abrasion speed of the grinding wheel by polishing of the grinding stone is approximately the same as that of the work, and the height from the surface on which the work is fixed is Dress material to become comparable with the workpiece fixed by the wax, mirror polishing method of the gap opposing face of the magnetic head is characterized in that polishing the workpiece. 2. A grindstone and a work sticking face plate which are respectively parallel to each other and rotate around different axes are provided, and the face plate and the grindstone are rotated while the work is fixed to the face plate. In the surface grinding machine for polishing a work, the work attachment surface plate is provided on a surface side on which the work is fixed, and has a stage having a surface to which a dress material is attached, and a surface of the stage on which the work is fixed. A surface grinding machine comprising: means for varying the height from the surface.