JPS61237212A - Polishing device for magnetic head - Google Patents

Abstract

PURPOSE:To uniform the gap of a heat after polishing by forming a rotary grindstone of a slanting part which increases in diameter at a specific angle and a large-diameter part which has the same constant diameter with its final expanded part, and bringing the grindstone into contact with the head from its small-diameter part and controlling the depth of the gap by the large- diameter part. CONSTITUTION:A head fitting jig 20 which has a recessed part 21 is movable in a direction T, and a head is supported on the jig at recessed fulcrum parts 24 and 25 formed in end parts 22 and 23 and rocked around the line 26 which connects the recessed fulcrum parts 24 and 25. Neither a support jig which operates the recessed fulcrum parts 24 and 25 nor a rocking jig is shown in a figure. A pressure screw 27 is provided engaging the fitting jig 20 threadably and this screw 27 fixes plural heads 29 mounted on a bottom surface 27 all together. The heads 29 are fixed to a small jig 30 by a screw 31 and mounted on the bottom surface 28 of the fitting jig 20 through the small jig 30. The small jig 30 is held at an interval with the adjacent small jig across a spacer 32 and the screw 27 gives a pressing force to the final spacer at the right end to fix them to the fitting jig 20 firmly.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to an apparatus for polishing a tape contact surface of a magnetic head in a magnetic head manufacturing apparatus.

Main) Prior Art Figures 6 (IL) to (d) show various magnetic heads used in small-sized VTRs called 8m/m video. In the same figure, (1) is the main core made of metal material such as Sendust or A7V steel, (2) is the gap, (3) is the reinforcing core%, (4) is ferrite, (5) is glass, (6) indicates the winding hole.

All of these magnetic heads have tape contact surfaces of 8
However, the conventional polishing device that performs this R has a rotating drum (7) similar to that of a VTR, as shown in Figure 7.
This was done by attaching a number head (8) and running a wrapping tape circle from the supply reel (9) to the take-up reel (2).As an extension of this method, Japanese Patent Laid-Open No. 19721/1983 There are some such as those listed.

In addition, in another conventional device, as shown in FIG.
8) attached to the base @, turn the rotating whetstone (13Iζ
On the other hand, rounding is performed by swinging within a predetermined angle range around the (0) point.

Furthermore, in another conventional device, as shown in Fig. 11, a plurality of heads (8) are fixed on the surface side of the mounting jig αΦ, and the mounting jig αΦ is fixed to the rotating grindstone shown in the figure. , Installation is done using jig Q
While moving l in the (T) direction, (C1) at both ends
(02) Swinging was performed using the point as a fulcrum.

(c) Problems to be Solved by the Invention As mentioned above, when a similar rotating drum (7) as shown in Fig. 7 is used and rounding is performed as shown in Fig. 8 with wrapping tape αυ, a certain amount of polishing is required. All you have to do is
Gap depth (D) of the magnetic head before polishing
Therefore, it is difficult to control the gap depth and radius shape with high precision. Before polishing, one of the causes of variations in the gap depth, etc. of the magnetic head is that the separate main core (1) and reinforcing core (3) are joined to form the magnetic head, as shown in Figure 9. In some cases, alignment may not be possible with high precision. The method shown in FIG. 7 also has the disadvantage that it is not possible to polish a large number of magnetic heads at once, and the workability is poor. This drawback also applies to the conventional example shown in FIG. It should be noted that the method disclosed in Japanese Patent Application Laid-open No. 58-19721 requires calculation of the amount of protrusion of the head, has a complicated structure, and is unsuitable for mass production. On the other hand, although the conventional example shown in FIG. 11 is superior in terms of mass production, it has another drawback as described below.The apparatus shown in FIG. 11 has two operating methods: a traverse cut method and a plunge cut method. In the traverse cut method, the head (8) moves to the left or right, and when it is completely separated from the grinding wheel (161), the grinding wheel is lowered by a certain amount in two directions.On the other hand, in the plunge cut method, the grinding wheel side is continuously lowered. While doing so, the head (8) is moved left and right by the jig αa.

In the transverse method, the distance traveled is at least
The total width of the alignment length (np) of many heads and the width of the grinding wheel (Wo) is required, and the cutting depth and movement speed are determined so that the head (8) will not be damaged by sudden cutting, and the number of times Since the head also has to be moved back and forth, processing efficiency is extremely poor. On the other hand, in the plunge cut method, efficient machining can be achieved by making the grinding wheel as wide as possible so that the grinding wheel αQ constantly grinds against a large number of heads (8). Since the entire surface does not wear uniformly, the parallelism between the grinding wheel surface αη and the mounting jig αΦ must be adjusted to within a few μm.
It was extremely difficult to maintain and was not appropriate. Furthermore, in order to use a wide grinding wheel, the size of the device increases accordingly, resulting in an increase in cost.

B) Means for Solving the Problems A holding means for holding a plurality of magnetic heads in an array, a rotating grindstone for polishing the heads, a means for relatively displacing the holding means and the rotating grindstone, and the holding means. A polishing device for a magnetic head comprising means for oscillating the grinding wheel at a predetermined center line of rotation, which comprises: an inclined part that enlarges the rotating grindstone at a certain angle; and a large diameter part that has the same diameter as the final part of the enlarged part. forming and abutting against the head from the small diameter portion,
A configuration in which the large diameter portion defines a gap depth.

(e) Operation The plurality of heads are moved from the inclined part of the rotary grindstone while being swung by the holding means.

In the - movement, the head is ground continuously little by little, and the final gap depth is defined by the large diameter part of the rotary grinding wheel. The gap depth is determined by the distance between the holding surface of the holding means that holds the head and the large diameter portion of the rotating grindstone. Therefore, even if the protruding amount of the tip of the head before polishing varies, it becomes uniform after polishing. The head is not cut all at once, but in small portions, so polishing is easy and there are no cracks or chips on the head.

(f) Example In Fig. 1 in which the present invention was implemented, @1 is a recess (21)
The head attachment is a jig that can move in the (T) direction, and is supported by the jig at the recessed support point +241 (25+) formed at the end (23). It is designed to swing around the wire bus connecting the defective fulcrum part circle (G).In addition, the concave defective fulcrum part c2AJ
The support jig and swing jig that act on (a) are not shown in the figure. For installation, the jig ■ is provided with a number of press screws that are screwed together, but this press screw is used to simultaneously attach multiple heads α placed on the bottom (support) of the recess (sha). It plays the role of fixing. As you can see from the enlarged view in Figure 2, the head is fixed to the small jig (1) with screws 0L, and the mounting is done through the small jig ω against the bottom @ of jig ■. It will be placed.

The distance between the small jig circle and the adjacent small jig is maintained through the spacer (2), but the dimensions of the spacer (2) and therefore the spacing between the small jigs can be appropriately selected. The screws come into contact with the final spacer (the spacer placed on the right end) and apply pressure directly to it, thereby suppressing the entire small jig ■ and the spacer ■, and attaching them to the jig ■ firmly fixed against the

Fig. 3 shows the head (support) fixed to the small jig (A), and as can be seen from this figure, the head has already been attached to the head base (to).

Therefore, the G is fixed to the small jig (2) via the head base (2). As shown in FIG. 5, the rotary grindstone is composed of an inclined part that expands at a certain angle (θ) and a large diameter part that has a constant diameter. The final enlarged part of the slope (Zheng) and the large diameter part are connected by the same diameter. Of course, the inclined part CI
5'1 and the large diameter portion 06) are integrally formed. Fig. 4 shows an enlarged view of the lower part of the whetstone as seen from the side. Grinding length W
1 is 35M1, spark-out length W2 is 15fi, grindstone slight inclination height h is 0°4fi, angle θ is θ=39
becomes. On the other hand, in FIG. 2, the distance between the depth end Do of the head and the spark-out surface (36&) of the grinding wheel (to), that is, the gap depth D, is 0.04fi, and the initial gap depth D of the head is 0.4M. . Next, the polishing operation will be explained. First, the nth head (29n
) is located on the left side as well as the grinding wheel, so move the jig opening to the left when attaching the attachment. Next, for installation, move the jig to the right at a machining speed of V while swinging the jig opening.

Separately from Figure 1, the machining speed that does not cause chips or chips on the head when the head and grindstone are in a constant polishing state is 10 μm/flag, based on experiments, so the machining speed in Figure 1 is the same. V is 10 μm v=,. 39/s1! c V-(], 9 # / l!Ic.In addition, the spark-out length [width of the large diameter part (to)] is W2= so that the spark-out time is completed in approximately 17 equations.
The weight was set at 15g.

Therefore, even if 15 heads were arranged and polished, the total processing time was 6 minutes. On the other hand, in the conventional example shown in FIG. 11, it takes 25 minutes under conditions to prevent cracks or chips from occurring. That is, according to the present invention, a machining speed eight times higher than that of the conventional method can be obtained.

As described above, in the present invention, the first to nth heads are moved from the inclined part of the grinding wheel toward the large diameter part in a manner similar to the traverse cutting method, so that the heads are in contact with each other.
Polish with just one movement.

During the movement, the head is swung so as to be stable. The large diameter part of the whetstone allows for precise finishing of gap depth dimensions.

(g) Effects of the invention According to the present invention, the head mounting means is attached to the surface,
The gap depth of the head is determined by the distance from the large diameter part of the rotating whetstone, so as long as you set the position of the whetstone and head mounting means so that this distance is determined accurately, The gap depth in the head is uniform and is not affected by variations before polishing. TFC, when mounting a large number of heads, the desired R attachment and gap depth can be obtained with one movement of the means. In addition, since the head is gradually and continuously polished, chips and cracks are prevented from forming on the head, and mounting a mounting means can increase the moving speed of the means, which has the effect of gradually improving work efficiency.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a polishing apparatus embodying the present invention. FIG. 2 is an enlarged view of the main part of FIG. 1. FIG. 6 is an enlarged view of a part of FIG. 1. Figure 4 and Figure 1g5 are the first
FIG. 2 is an explanatory diagram and a perspective view of the main parts of the device in the figure. FIG. 6 is a perspective view of the part to be polished. FIG. 7 is a schematic diagram of a conventional polishing apparatus, and FIGS. 8 and 9 are explanatory diagrams thereof. FIG. 10 is a schematic diagram of another conventional example. FIG. 11 is a schematic diagram of a still different conventional example. ■・・・Head installation is done using jig (holding means), ■・
...Head, ■...Rotation center line, (Foundation)
...Rotary grindstone, can...Slope part, 31i
1...Large diameter part. Dega Sanyo Electric Co., Ltd. Oto Bento Attorney Sano Shizuo ＾ r) Figure 4 Figure 7 Figure 8 Figure 8 Spear figure

Claims (1)

[Claims] (1) Holding means for arraying and holding a plurality of magnetic heads; a rotating grindstone for polishing the heads; means for relatively displacing the holding means and the rotating grindstone; In a polishing device for a magnetic head comprising means for oscillating, the rotary grindstone is formed of an inclined part that expands at a certain angle and a large diameter part that has a constant diameter that is the same as the final part of the enlarged part, and A polishing device for a magnetic head, in which the small-diameter portion comes into contact with the magnetic head, and the large-diameter portion defines a gap depth.