JPH0691432A - Electrolytic complex buffing method - Google Patents

Abstract

PURPOSE:To enhance the efficiency of an electrolytic complex buffing method by enabling electrolytic complex buffing to be carried out continuously for a long time in the electrolytic complex buffing process. CONSTITUTION:Abrasives are additionally supplied to electrolytic solution in an electrolytic complex buffing process which is carried out as follows: a buff 13 having an electrode 14 at the one end of a rotary shaft 12 is set over the designed surface 2 of raw material 1 for an automobile wheel, which is fixed on a rotary table 11, electrolytic solution is supplied between the electrode 14 and the raw material 1 for an automobile wheel, and concurrently electric discharge machining is carried out with electrolytic current applied thereto, and simultaneously buffing is carried out by the rotary shaft 12 with the buff 13 rotatably driven.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrolytic composite buffing method for simultaneously performing electrolytic processing and buffing on the surface of a work material.

[0002]

2. Description of the Related Art Conventionally, there is a so-called electrolytic buffing method in which electrolytic processing and buffing are simultaneously performed in order to efficiently and effectively finish a surface of a workpiece (for example,
See Japanese Patent Publication No. 60-48289).

According to this type of electrolytic composite buffing, a passive oxide film is formed on the surface of a workpiece by electrolytic action,
Since the convex portion can be efficiently removed by the buff, the surface of the material to be processed can be efficiently a good finished surface.

Even in this type of electrolytic composite buffing, it is necessary for the buff to have abrasive grains in the contact area between the buff and the workpiece in order to remove the workpiece.
Abrasive grains of this type are worn away as the material to be processed is processed.

In the conventional electrolytic composite buffing, a buff in which abrasive grains are adhered or applied is used. When the buff is used, the abrasive grains perform the required processing.
After performing a certain amount of processing, the buff is replaced with a new one to update the abrasive grains and avoid problems such as a decrease in processing efficiency.

[0006]

Therefore, in the conventional electrolytic composite buffing, it is possible to continuously process for a long time in terms of electrolytic processing, but relatively short in terms of buffing. The abrasive grains need to be renewed every time, which necessitates a stop of the work, which reduces the efficiency of the electrolytic composite buffing.

The present invention has been made under such circumstances, and in the electrolytic composite buffing method of this type, the electrolytic composite buffing can be continuously performed for a long time so that the electrolytic composite buffing is performed. The purpose is to improve the efficiency of.

[0008]

In order to achieve this object, the invention according to claim 1 provides a buff having an electrode at one end of a rotary shaft on the surface of a workpiece fixed on a machining table. In an electrolytic composite buffing method in which an electrolytic solution is supplied between the electrode and a workpiece and an electrolytic current is passed to perform electrolytic processing, and at the same time, the buff is rotationally driven by the rotating shaft to perform buff processing, It is characterized in that abrasive grains are added to the electrolytic solution and supplied.

[0009]

According to the invention described in claim 1, a buff having an electrode is provided, an electrolytic solution is supplied between the electrode and a material to be processed to perform electrolytic processing, and abrasive grains are contained in the electrolytic solution. The abrasive grains used for buffing are continuously supplied to the contact area between the buff and the surface of the workpiece.

Therefore, the abrasive grains in the contact region are continuously metabolized along with the supply of the electrolytic solution, and it is possible to reduce the stoppage of the work for buffing which has been conventionally performed.

Therefore, in the electrolytic composite buffing method of the present invention, good buffing can be performed for a long time by using new abrasive grains that are continuously supplied, so that a good finished surface can be obtained continuously. Therefore, the working efficiency of the electrolytic composite buffing can be improved.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to embodiments shown in the drawings. In this embodiment, the present technology is applied to the design surface of an aluminum alloy automobile wheel as a molded product formed by a mold. . The design surface is a surface that faces the outside of the vehicle body and constitutes a part of the appearance of the vehicle when the vehicle wheel is mounted on the vehicle.

First, an automobile wheel material 1 as a workpiece is cast by pouring a molten aluminum alloy (for example, AC4CH) into a mold having a required shape.

The wheel material 1 for an automobile thus obtained has a dimensional accuracy as an automobile wheel after being taken out of the mold, the weir and the like are removed, and predetermined machining is performed at a required position. It has been secured.

In the automobile wheel material 1, a large number of irregularities are formed on the design surface 2 of the spoke portion 3, the through holes 4, the hub portion 5 and the rim portion 6 by a mold in view of design requirements. (See Figures 1 and 2).

The design surface 2 (corresponding to the surface referred to in the present invention) of the automobile wheel material 1 is subjected to the required rough finish and intermediate finish, and then the electrolytic composite buffing method according to the present invention is performed. Finally the design side 2
Is formed on the finished surface in a bright state.

That is, the electrolytic composite buffing method of the embodiment is as follows (FIGS. 1 and 2).

In this electrolytic composite buffing method, the wheel material 1 for an automobile is designed on the rotary table 11 (corresponding to the machining table in the present invention) with its center aligned with the rotation center O of the rotary table 11. 2 is fixed in an upward horizontal posture, a buff 13 is attached to an end plate 12b at the lower end of a rotary shaft 12 hanging from above, and the design surface 2 is polished by the lower end surface of the buff 13. .

The rotary table 11 is driven to rotate at a low speed during processing, and sequentially displaces the processed portion of the vehicle wheel material 1 as a workpiece by the buff 13 in the circumferential direction. 11 is adapted to reverse its rotation direction every appropriate time (for example, 30 seconds).

Then, the buff 13 in this embodiment
Is formed almost entirely of an open-celled sponge material. In the center portion of the buff 13 in the thickness direction, an electrode 14 is substantially parallel to the end plate 12b for performing an electrolytic processing function described later. Are arranged in a plane (see FIG. 3).

The sponge material forming the buff 13 has a high expansion ratio of, for example, 3 to 5 times, and is an extremely flexible material as compared with the conventional buff. The buff 13 is not limited to the sponge material, and a buff made of another material may be used as long as it is flexible to the same degree.

The buff 13 of this embodiment has a base portion 13a above the electrode 14 and a tool portion 13b below the electrode 14, and the tool portion 13b performs the original polishing function as a buff. The base portion 13a has a main function of holding the electrode 14 and the tool portion 13b arranged therebelow.

In this embodiment, these bases 13a are
The tool portion 13b and the tool portion 13b are both formed of the same kind of sponge material, but different kinds of materials may be used in combination.

As described above, the base portion 13a of the buff 13 is
Since the tool portion 13b and the tool portion 13b are formed of an extremely flexible sponge material, the buff 13 is easily bent as a whole, and the buff 13 has unevenness even if the design surface 2 has irregularities.
The lower surface of can reliably maintain contact with the design surface 2.

Then, the electrode 14 of the buff 13 is
It is made of a wire mesh as a flexible and bendable sheet-like material, and has a shape that matches the planar shape of the buff 13.

In this buff 13, the electrode 1
By arranging the base portion 13a made of a sponge material on the upper side of 4, an effect peculiar to the electrolytic composite buff processing method of the present application is exhibited, which point will be described after the description of the processing method according to this embodiment.

Such a buff 13 is mounted on the lower surface of the end plate 12b via an insulating plate 18, and the DC power source 1 is provided between the electrode 14 and the automobile wheel material 1.
7, the electrode 14 is connected to the plus side, and the design surface 2 of the automobile wheel material 1 is connected to the minus side.

The rotary shaft 12 for supporting the buff 13 at the lower end is held by a lifting device 15 composed of a hydraulic cylinder or the like, and the pressing force of the buff 13 on the design surface 2 is, for example, 1 kgf. It is given as a small item of less than / cm ² .

Further, the rotating shaft 12 is driven at, for example, 300 rpm so that the rotating speed of the buff 13 becomes an extremely low speed of about 10 m / sec or less. In the case of this embodiment, The rotation speed of the buff 13 is, for example, 4 m / sec.

This enables the tool portion 13b made of a flexible sponge material which constitutes the buff 13 to be surely deformed following the unevenness while maintaining the contact state with the unevenness of the design surface 2. This is because.

The rotation direction of the rotary shaft 12 is driven so as to match the rotation direction of the rotary table 11, and when the rotation direction of the rotary table 11 is reversed to the opposite direction. In addition, the rotating shaft 12 is pulled up by the elevating device 15 and the lower surface of the buff 13 is separated from the design surface 2 upward.
The rotation direction of 2 is also reversely driven.

Therefore, even if the rotating direction of the rotating table 11 is reversed, the rotating direction of the rotating table 11 and the rotating direction of the buff 13 are always maintained in the same direction.

A shaft hole 12a is formed in the rotary shaft 12, and an electrolytic solution is supplied from the shaft hole 12a to the lower surface of the buff 13 through the base portion 13a, the electrode 14 and the tool portion 13b (FIG. (See arrow 3).

Further, in this embodiment, as shown by the phantom line in FIG. 4, an electrolytic solution nozzle 16 for supplying the electrolytic solution toward the contact portion between the buff 13 and the design surface 2 is installed.

The shaft hole 12a and the electrolyte solution nozzle 1
The electrolytic solution supplied from 6 fills the periphery with the electrolytic solution by infiltrating the sponge material forming the tool portion 13b between the electrode 14 and the design surface 2, and the DC power supply 17 is supplied by these polishing solutions. An electrolytic circuit from
The electric current enables the electrolytic action on the surface of the design surface 2.

The electrolytic solution in this embodiment contains sodium nitrate for electrolytic action in an aqueous solution containing a surfactant.

Further, this electrolyte is buffed as described above.
Since it is supplied toward the contact area between the buff 13 and the design surface 2, abrasive grains for buffing by the buff 13 are added to the electrolytic solution.

The abrasive grains in this example have a particle size of 10 μm.
As described above, since the electrolytic solution is continuously supplied to the contact area between the buff 13 and the design surface 2 as described above, the electrolytic action and the supply of fresh abrasive grains are continuously performed. Can be done

The amount of electrolyte supplied from the shaft hole 12a of the rotary shaft 12 and the polishing liquid nozzle 16 is, for example, 100 cc / min.
That is all.

As described above, in the above-described processing method, the electrolytic processing and the buffing are simultaneously performed in a combined manner, that is, the so-called electrolytic composite buffing method is continuously performed, and the processing efficiency is higher than that of the normal electrolytic processing or the buffing. Good and
Since work stoppage as in the conventional case is reduced, work efficiency is improved.

Since the supply of the electrolytic solution from the electrolytic solution nozzle 16 is continued even when the rotating direction of the rotary table 11 is reversed, the buff accompanying the reversal of the rotary table 11 is performed. At the time of rising of the buff 13, the electrolytic solution is sprayed toward the portion that was immediately below the buff 13 so that the buff debris and other foreign matter that are interposed between the buff 13 and the design surface 2 are effectively discharged. There is an advantage that can be removed.

Particularly, when the material to be processed is an aluminum alloy, the crystal of silicon is exposed on the surface by the electrolytic processing of the surface, but in this embodiment, the wet buffing is performed simultaneously with the electrolytic processing. There is also an advantage that the buff can remove the silicon exposed on the surface.

By the way, in the buff 13 of the above-mentioned embodiment, the base 13a made of a sponge material is arranged above the electrode 14 because the following peculiar effect is exhibited.

That is, in the case where the electrolytic processing method and the buffing method are combined as in the above-described embodiment, in the electrolytic processing method, the distance between the electrode 14 and the design surface 2 depends on the processing efficiency and the finished surface. Is an important control element that has a large effect on

In the buffing method, the buff 13
It is important to press the lower surface of the design surface 2 against the design surface 2 with an appropriate pressure in order to obtain a good finished surface.

In particular, in a molded product such as an automobile wheel material 1 in which irregularities are formed on the surface to be finished, it is required that the lower surface of the buff 13 keeps contact with the surface regardless of irregularities. Flexible buff 13 for this
Therefore, the amount of change in the height position of the electrode 14 from the design surface 2 is large due to the pressing force applied to the surface of the buff 13.

A request for such a buffing method,
The contradiction between the electrolytic processing method and the requirement for the height position of the electrode 14 is derived from the essence of the electrolytic composite buffing method.

In the buff 13 of the above embodiment, the electrode 14
The base portion 13a made of a sponge material is provided on the upper side of the above in order to alleviate the influence of the contradiction caused by the requirements of both processing methods and to surely obtain a good finished surface.

The function of the base portion 13a will be specifically described below with reference to FIG.

FIG. 4A shows a situation in which the surface 22 of the flat work material 21 is subjected to electrolytic composite buffing.

In this case, since a required pressing force is applied to the buff 13, the lower surface of the buff 13 is pushed upward by the dimension m from the position in the free state shown by the phantom line. The distance between the surface 22 of the work material 21 and the end plate 12b is reduced accordingly.

Therefore, the electrode 14 is connected to the end plate 12
If it is fixedly attached to b, the distance between the electrode and the surface of the material to be processed changes by the dimension m, so that the electrolytic processing conditions change significantly.

However, in the buff 13, the electrode 14
Through the base portion 13a made of a sponge material, the rotary shaft 1
Since it is provided so as to be elastically movable back and forth in the axial direction of 2, the electrode 14 is pushed up from the electrode position P in the free state by the dimension n, and the displacement amount of the electrode 14 from the surface 22 of the workpiece 21 is dimension m-
It is reduced to the amount corresponding to n.

The current flowing from the electrode 14 to the surface 22 concentrates on the portion where the distance between them is shortest, but since the displacement amount is reduced as described above, the concentration of the current is reduced and the unevenness of the electrolytic processing is caused. It is possible to obtain a uniform finished surface by suppressing the occurrence of

That is, according to the buff 13, the buff 1
With the setting of the pressing force of 3, the frequency of adjusting the electrolysis conditions is low, and there is an advantage that a good finished surface can be easily obtained.

When such a flat surface 22 is subjected to the electrolytic composite buffing method, the electrode 14 may be made of a material having a high rigidity rather than a flexibility.

FIG. 4B shows a situation in which the electrolytic composite buffing is performed on the surface 24 of the work material 23 such as a molded product having irregularities on the surface.

In this case, the same effect as described above is locally exerted under the additional condition that the electrode 14 is formed of a flexible sheet-like material such as a wire mesh.

That is, the buff 13 is the surface 2 of the workpiece 23.
4 is located on the convex portion 24a, the buff 13 at that portion.
The lower surface is pushed upward by the height dimension m of the convex portion 24a, and accordingly, the electrode 14 is locally displaced upward by the dimension n at the position corresponding to the convex portion 24a.

In this case, if the electrode 14 does not have flexibility, the distance between the electrode 14 and the surface 24 of the workpiece 23 is smaller by a dimension m than that of the portion other than the convex portion 24a. Electrolytic current flows intensively in the convex portion 24a,
Since a is excessively electrolyzed and the current flowing around it is sparse, the electrolysis is likely to be insufficient.

However, in the buff 13, the electrode 14 is also locally displaced upward by the dimension n as described above, so that the electrode 14 at the portion corresponding to the convex portion 24a.
The distance between the surface of the workpiece 23 and the surface 24 of the workpiece 23 is only reduced by mn, and the density of the electrolytic current is not so high as described above, so that the electrolytic action can be relatively uniformly generated.

Therefore, according to the buff 13 of the above-mentioned embodiment, the occurrence of electrolytic machining unevenness is reduced, and it becomes easy to obtain a good finished surface.

The buff having such an effect is not limited to the one in which the base portion 13a is made of the sponge material as described above.
It can be implemented with various materials and structures.

For example, the buff 31 having the structure shown in FIG. 5 functions almost similarly. It should be noted that, in the following, items common to those of the buff 13 of the above-described embodiment are denoted by the same reference numerals and description thereof is omitted, and only differences from the buff 13 are described below.

That is, the buff 31 of this modified example uses a ring-shaped cushioning material 33 having an annular air chamber 32 therein instead of the base portion 13a of the buff 13 described above, and the ring-shaped cushion material 33 is used. On the lower surface of the cushion material 33, the electrode 14 made of a wire mesh as a flexible sheet material is provided.
The tool part 13b is attached via the.

Also in this buff 31, due to the pressing force applied to the buff and the unevenness of the surface of the material to be processed, the ring-shaped cushion 33 is moved by the air chamber 32 thereof as in the buff 13.
Elastic deflection can be generated wholly or locally, which reduces the change in the distance between the electrode 14 and the surface of the work piece as compared with the prior art. It becomes easy to secure the surface.

In all of the embodiments described above, the rotary shaft 12 is arranged in the vertical direction, that is, a so-called vertical shaft type, but in the present invention, as shown in FIG. It can be implemented even with a horizontal axis type disposed at.

The embodiment shown in FIG. 6 will be described below.

In FIG. 6, the buff 35 is a horizontal axis type in which the rotary shaft 12 is installed substantially horizontally along the design surface 2. Therefore, the buff 35 has its outer peripheral surface brought into contact with the design surface 2 for polishing, and the same electrolytic solution as described above is supplied from the electrolytic solution nozzle 16.

The buff 35 is provided so as to surround the outer circumference of the rotary shaft 12, and has a base portion 35a made of a sponge material similar to that of the above embodiment, and a cylindrical shape concentric with the rotary shaft 12 outside the base portion 35a. The formed electrode 36 and the tool portion 35b formed of the same sponge material on the outer side of the electrode 36 are integrally formed as a three-layer structure.

A DC power supply 17 is interposed between the electrode 36 of the buff 35 and the design surface 2 to form an electrolytic circuit.

Even in the case of such a horizontal axis type,
The same function as that of the vertical shaft type can be achieved, and the same effect as the above can be obtained.

In particular, since the horizontal axis type is used, the shape of the contact portion between the tool portion 35b and the design surface 2 as the workpiece becomes linear, so that the electrolytic current can easily flow uniformly and the surface pressure can be reduced. Since it increases, the polishing power is strong, and there is an advantage that the electrolytic composite buff polishing can be efficiently performed with a relatively small current.

[0074]

As described above, according to the first aspect of the invention, the buff having the electrode is provided, and the electrolytic solution is supplied between the electrode and the material to be processed to perform the electrolytic processing. Since the abrasive grains are added to the electrolytic solution, the abrasive grains used for buffing are continuously supplied to the contact region between the buff and the surface of the workpiece.

Therefore, the abrasive grains in the contact region are continuously metabolized along with the supply of the electrolytic solution, and it is possible to reduce the stoppage of the work for buffing, which has been conventionally performed.

Therefore, in the electrolytic composite buffing method of the present invention, good buffing can be performed for a long time by using new abrasive grains that are continuously supplied, so that a good finished surface can be obtained continuously. Therefore, the working efficiency of the electrolytic composite buffing can be improved.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an electrolytic composite buffing method of an example.

FIG. 2 is a top view of FIG.

FIG. 3 is an explanatory sectional view of a buff.

FIG. 4A and FIG. 4B are explanatory diagrams of the operation state of the buff.

FIG. 5 is an explanatory cross-sectional view of a modified buff.

FIG. 6 is an explanatory cross-sectional view of another embodiment.

[Explanation of symbols]

 1 Automotive Wheel Material (Workpiece) 2 Design Surface (Surface) 11 Rotating Table (Processing Table) 12 Rotating Axis 13 Buff 14 Electrode

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[Procedure amendment]

[Submission date] July 3, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0034

[Correction method] Change

[Correction content]

Further, in this embodiment, as shown by the phantom line in FIG. 2, an electrolytic solution nozzle 16 for supplying an electrolytic solution toward the contact portion between the buff 13 and the design surface 2 is installed.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0046

[Correction method] Change

[Correction content]

In particular, in a molded product such as an automobile wheel material 1 in which irregularities are formed on the surface to be finished, it is required that the lower surface of the buff 13 keeps contact with the surface regardless of irregularities. Flexible buff 13 for this
Is used, the amount of change in the height position of the electrode 14 from the design surface 2 is large.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0054

[Correction method] Delete

[Procedure amendment 4]

[Document name to be amended] Statement

[Name of item to be corrected] 0058

[Correction method] Change

[Correction content]

In this case, the current flowing from the electrode 14 to the surface 24 is concentrated in a region where the distance between the two is shortest. Then, in the illustrated case, the same effect as the above is locally exerted under the additional condition that the electrode 14 is formed of a flexible sheet-like material such as a wire mesh.

[Procedure Amendment 5]

[Document name to be corrected] Drawing

[Correction target item name] All drawings

[Correction method] Change

[Correction content]

[Figure 1]

[Fig. 2]

[Figure 3]

[Figure 4]

[Figure 5]

[Figure 6]

Claims (4)

[Claims] 1. A buff having an electrode at one end of a rotating shaft is provided on the surface of a work piece fixed on a working table, an electrolytic solution is supplied between the electrode and the work piece, and an electrolytic current is passed through the buff. In the electrolytic composite buffing method, in which electrolytic buffing is performed by simultaneously rotating the buff by the rotating shaft to perform buffing, an abrasive grain is added to the electrolytic solution and supplied. Buffing method. 2. The electrolytic composite buffing method according to claim 1, wherein the electrode is elastically movable in the axial direction with respect to the rotating shaft. 3. The electrolytic composite buffing method according to claim 2, wherein the electrode is formed of a flexible sheet-like material, and the electrode is placed along a plane perpendicular to the axial direction of the rotating shaft. An electrolytic composite buffing method characterized by the above. 4. The electrolytic composite buffing method according to claim 3, wherein a wire net is used as the sheet-shaped material of the electrode.