JPS62213960A - Lapping jig - Google Patents

Abstract

PURPOSE:To provide processing of a super-flat surface with good productivity by using a pneumatic bearing, and applying restrictive force in the radial direction during lapping between a holder and an outer ring. CONSTITUTION:Compressed air 6 supplied from an air supply port 5 intrudes in a gap (a) between an air supply ring 4 and an outer ring 3, and thereafter is partially led to outside from a' while the rest intrudes in a gap (b) between the outer ring 3 and a holder 2 from a nozzle 7 furnished at the outer ring 3 to be then released to outside. This causes the holder 2, outer ring 3 and air supply ring 4 out of contact from one another, and further, the nozzle 7 is located in the position dividing the outer ring circumference equally, so that it is difficult for the holder to displace in the radial direction. This lapping jig is located in a correction ring of a lapping machine, and when the lapping surface board beings rotating, a flange 3' at the bottom of the outer ring 3 comes in contact with the correction ring, and now the outer ring 3 rotates and the holder 2 also rotates. Thus a specimen 1 can be lapped without procession to provide high precision surfaces easily.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to lapping the surface of a sample made of hard and brittle materials such as general metal materials and ceramics, and is particularly applicable to high-precision flat lapping. The present invention relates to providing a suitable wrapping jig.

[Background of the invention]

In order to lap the surface of a sample into a highly accurate flat surface, it is very important that the lap surface plate maintains a highly accurate flat shape. It is normal for the planar shape of the board to constantly change. In order to keep the planar shape of the lapping plate in a highly accurate plane forever, many correction wheel type lapping machines, such as those seen in Shibayama Kikai's Ni Kataroku, have been adopted and commercially available. This lapping machine is designed to keep the lapping surface plate in a highly accurate flat shape forever by rotating the correction shaft, thus allowing high-precision flat lapping to be performed at all times.

To lap the target sample using this correction wheel type lapping machine, you can either place the sample directly into the correction shaft, or fix the sample to some kind of holder with adhesive, etc., and then attach the holder to the correction wheel. This is done by placing it inside and operating the wrapping machine. In particular, the latter method is often used when the sample is a small item or a non-circular item such as a rectangular item. FIG. 6 shows a sketch of a lapping jig that has conventionally been commonly used in such cases. After the sample 1 is fixed to the holder 2 with adhesive, it is inserted into the outer shaft 3. One set of lapping jig referenced in this way is placed into the correction shaft, and sample 1 is lapped. In this case, the holder 2 and the outer ring 3 are not fixed to each other. In other words, the holder 2 is free in the vertical direction within the outer ring 3, and sinks downward as the lapping process progresses. By doing this, the holder 2 can be easily taken out and the sample 1
- It has the advantage of facilitating intermediate inspections.

However, the above-mentioned wrapping jig does not have a holder 2.
Because there is a clearance b (usually about 0.02 mm) between the holder 2 and the outer shaft 3, there may be some precession MI in the holder 2 during lapping.
I will be playing jj. This precession becomes particularly noticeable when the planar shape of the lap plate is poor. Therefore, the lapped sample 1 has the disadvantage that its surface generally has a convex shape. Further, such precession is particularly likely to occur when the surface area of the sample 1 is smaller than the surface area of the holder 2. To prevent this, holder 2 and outer ring 3
It is necessary to minimize the effect of the gap between the

As a common method for this purpose, for example, as described in "Crystal Processing and Surfaces" published by the Physical Society of Japan, page 73, a method is known in which multiple Yatoi are placed around the sample 1 and lapping is performed. ing.

That is, since the surface area of the lap value is increased by using the Yatoi, the precession of the holder 2 is reduced, and the sample 1 can be lapped with high precision. but,
There is a tendency that a Yatoi must be provided, and that a good effect cannot be obtained unless the Yatoi is made of the same material as Sample 1.
There are practical problems. In addition, with this method, although the precession is reduced to some extent, it is not sufficient, and the flatness is reduced to λ/1, for example.
In order to obtain a plane with a diameter of 0 (λ: wavelength of light) or less, it is necessary to take measures to suppress even more active precession.

However, the precession described above is also affected by the load W applied to the sample 1. In other words, the heavier W is, the more force it pulls in the lateral direction, and the more likely it is to cause precession, so to prevent precession, we must be careful about the load applied to sample 1. It is desirable that the means for preventing differential movement also include a mechanism that allows fine adjustment of the load.

[Problem that the invention seeks to solve]

SUMMARY OF THE INVENTION An object of the present invention is to provide a lapping jig that eliminates the drawbacks of the prior art described above and can process ultra-flat surfaces with high productivity.

[Means for solving problems]

In order to achieve the above object, the present invention uses an air bearing to prevent the holder 2 and the outer ring 3 during lapping.
It is characterized by applying a regulating force in the radial direction between the two and further adjusting the load applied to the sample during lapping.

[Effect]

By using an air bearing type lapping jig, the holder and the outer ring are in a non-contact state. Moreover, the holder is restricted from being displaced in the radial direction by the compressed air ejected from the ejection nozzle provided in the outer ring. Therefore, the sample fixed in the holder is lapped without precessing, and a highly accurate surface is easily obtained.

〔Example〕

Hereinafter, a detailed explanation will be given based on one embodiment of the present invention.

[Example 1] FIG. 1 is a sketch showing an example of the wrapping jig of the present invention. The difference from the conventional wrapping jig shown in FIG. 6 is that the outer shaft 3 is an air bearing, so the holder 2 is not in contact with the outer shaft 3. This lapping jig set is inserted into the correction shaft of the above-mentioned lapping machine, and the sample 1 is lapped. At this time, it is necessary to supply compressed air 6 from a separately provided compressed air source to the rotating outer shaft 3, and an air supply ring 4 is provided as a means for realizing this. By doing this, the holder 2 and the outer ring 3 rotate very smoothly during the lapping process, for example in the direction of the arrow shown in the figure, but at the same time, the compressed air 6 is continuously supplied to the outer ring 3 during one rotation. Ring 4 is
It does not rotate and remains at that position. The operation will be explained below.

Compressed air 6 is supplied from an air supply port 5 provided in the air supply ring 4, and after entering the gap a between the air supply ring 4 and the outer ring 3, a part of it escapes to the outside through a', but the rest escapes. The compressed air 6 passes through a jet nozzle 7 provided on the outer ring 3, enters the gap b provided between the outer ring 3 and the holder 2, and is then discharged to the outside. With this configuration, the holder 2, the outer ring 3, and the air supply ring 4 are brought into a non-contact state with each other. The jet nozzles 7 are provided at positions that equally divide the circumference of the outer ring 3 (preferably at least four equal parts at intervals of 90 degrees or more), and the compressed air 6 jetted from each can press the holder 2 with equal force. become. In other words, the holder 2 is restricted so that it is difficult to displace in the radial direction.

The lapping jig of the present invention, which operates as described above, is placed in the correction shaft of the lapping machine.

When the multi-face plate begins to rotate, the collar 3' provided at the bottom of the outer ring 3 comes into contact with the correction shaft, causing the outer ring 3 to rotate. The holder 2 also rotates, and the sample 1 is lapped.

The main purpose of the present invention is to prevent precession of the specimen during lapping, and the jet nozzles 7 for compressed air 6 are provided in two stages in the outer ring 3. The interval is Q
By setting Q to an appropriate interval, precession of the holder 2, that is, the sample 1, becomes less likely to occur. It has been experimentally confirmed that Q preferably satisfies at least the relationship Q≧D, where D is the outer diameter of the holder 2. However, making Ω sufficiently large is accompanied by difficulty in manufacturing, so in practice it is sufficient to set Q = c D. Also, in the above example, the jet nozzle 7 is Although it is expected that increasing the number of stages will further prevent precession, considering the difficulty of I2 production, it is practical to use two or three stages. It becomes a place.

The compressed air 6 generally has a supply pressure of 4 to 5 kIcf/-. Appropriate values for the clearances between each part are approximately as shown below.

Clearance a between the air supply ring 4 and the outer ring 3 = 1. ~2IIWl
Clearance a' between air supply ring 4 and outer ring 3 = 0.0151
Gap between Lm outer wire 3 and holder 2 b = 0, 0
2 mm [Example 2] FIG. 2 shows an example in which a load fine adjustment mechanism is added to the above-mentioned Example 1. In this embodiment, an air pocket 10 is formed between the holder 2 and the outer ring 3. Clearance b' between holder 2 and outer ring 3.

b' = 0.005++n, compressed air 6
This air pocket 10 should be filled with as much as possible. The compressed air 6 accumulated in the air reservoir 10 is configured to be discharged outside through a passage 11 provided in the holder 2 and further through a flow rate regulating valve 12. By adjusting the flow area adjustment valve 12, the lap load applied to the sample 1 is adjusted as follows. In other words, by "opening" the flow rate regulating valve 12, a large lap load (411 weights corresponding to the weight of the holder 2) is applied, and by "squeezing" it is a light load. The reason why the load becomes light is that by throttling the flow area regulating valve 12, there is no place for the compressed air 6 to escape, and the air pocket 10 is filled with a force that pushes the holder 2.

The lapping load should be appropriately selected in consideration of the material of the sample, the abrasive grains used, processing efficiency, etc.

Conventionally, in order to increase the weight of the wrapped load y1, it has been common practice to add a weight to the holder 2.

This is fine if you want to make it heavier, but it was difficult to make it lighter. Therefore, it is common practice to use a holder that is originally light and adjust the lap load with an additional weight.

In this embodiment, in particular, the lap load can be easily adjusted, and moreover, even slight control is possible. Therefore, for example, it is a particularly effective lapping jig for lapping high-quality surfaces where a damaged layer is a problem. Furthermore, a small lapping load will reduce machining efficiency, but since a large load is not applied to the lapping face plate, it will not deform and high-precision lapping can be performed. Furthermore, as mentioned above, the precession is also reduced, and the sample is finished with a highly accurate surface.

In Examples 1 and 2 described in detail below, an example was described in which an air bearing was used as a specific means for suppressing the precession of the holder 2. The same effect is expected not only with a drawing type but also with a fixed drawing type, a porous sleeve type, etc.

Furthermore, the above-mentioned precession M movement suppressing means is not particularly limited to air bearings, and for example, ball bearings or the like may be used.
FIG. 3 is a plan view showing a schematic diagram of an example of the wrapping jig. A ball bearing 20 is provided on the outer ring 3, and the holder 2 is inserted into it.

The three ball bearings 20 are attached to the outer circumference of the holder 2 at positions so as to circumscribe the holder 2 with almost no gaps. When inserting the holder 2, the outer ring 3 is slightly elastically deformed, making it surprisingly easy to insert the holder 2. In this way, the holder 2 is prevented from being displaced in the radial direction, and can move relatively smoothly in the upward direction.

According to the method described above, the holder 2 rotates with precession suppressed, and the sample 1 is lapped with very high precision. In particular, in the past, high-precision lapping could not be performed without the use of a yatoi, but with the lapping jig of the present invention, there is no need to use a yatoi.

Note that while the above-mentioned lapping process has only been described in terms of a method in which the lapping jig shown in FIG. 1 or 2 is inserted into the correction shaft, the method is not limited to this.
For example, as shown in FIG.

A similar lapping process can also be performed by supporting the lower collar portion 3' on the outer ring 3 via the small ring 30. In this case, the outer ring 3 also serves as a correction shaft, and the overall configuration of the lapping machine is further simplified. The effect of the lapping jig at this time is no different from when using a correction axis.

Equivalent precision of processed products can be obtained.

Furthermore, as shown in FIG. 5, it is also possible to provide a support 40 on the lapping machine, fix the lapping jig of the present invention to this support 40, and perform lapping by sliding the support 40 horizontally. It is. In this case, since the entire surface of the lapping plate is used uniformly, more efficient lapping can be performed.

〔Effect of the invention〕

According to the lapping jig of the present invention, since the holder rotates without precession, the sample can be lapped into a highly accurate flat surface. In other words, when comparing the lapping conditions under exactly the same conditions, when using a conventional jig, for example, 20 x 20
+m'' samples can achieve a flatness of about 1 μm, but the lapping jig of the present invention improves the flatness to about 0.1 μm or less, which improves the flatness by about one order of magnitude or more.

Conventionally, a Yatoi is used to perform high-precision lapping, but with this lapping jig, even a single sample can be lapped with high precision, so there is no need to use a Yatoi. However, if Yatoi is also used, ultra-high precision lapping will be possible.

Furthermore, the lapping jig of the present invention can add a function to reduce the lapping load, so by activating this function especially when the lapping process approaches the end Y, the sample can be finished with higher precision.

[Brief explanation of drawings]

Fig. 1 is a sketch showing one embodiment of the wrapping jig of the present invention, Fig. 2 is a sketch showing another embodiment of the wrapping jig of the present invention, and Fig. 3 is an embodiment of the wrapping jig of the present invention. 4 is a partial sectional view showing an example of a method for supporting the wrapping jig of the present invention, and FIG. 5 is a partial sectional view showing another method for supporting the wrapping jig of the present invention. 6
The figure is a sketch showing a conventional wrapping jig. 1... Sample, 2... Holder, 3... Outer ring, 3'
...Brim portion, 4...Air supply ring, 5...Air supply port,
6...Compressed air. 7...Blowout nozzle, 10...Air pocket, 11...
・Passage, 12...Flow rate adjustment valve, 20...Ball bearing, 3
0...Small ring, 40...Strut, a...Gap between the air supply ring and outer ring, a'...Gap between the air supply ring and outer ring, b...Gap between the outer ring and holder, b'...Gap between outer ring and holder, α...Span of jet nozzle, D
...Holder outer shell 2 openings 3rd figure

Claims (1)

[Scope of Claims] 1. A lapping jig comprising a holder and an outer ring, which is characterized by having a function of suppressing radial displacement of the gap between the holder and the outer ring. 2. The lapping jig according to claim 1, wherein the suppressing means is of an air bearing type. 3. The wrapping jig according to claim 1, which is equipped with a load reduction mechanism.