JPH0655346A - Electrochemical composite machine - Google Patents

Abstract

PURPOSE:To machine a workpiece into desirable surface roughness and flatness with less machined distortion by removing a passive coat, formed on the workpiece side, by a grinding wheel of high rigidity while moving this grinding wheel at about the same speed as the growing speed of the passive coat. CONSTITUTION:An electrochemical composite machine using a grinding wheel 4 formed of fixed abrasive grain is provided with a cutting edge speed switching circuit 9. The cutting edge speed switching circuit 9 is formed in such a way as to switch the set value of a cutting edge speed setting circuit 11 to the fine grinding cutting edge speed V1, that is, about the same speed as the growing speed of a passive coat formed on the workpiece W side by electrochemical action generated between the grinding wheel 3 and the workpiece W. From the time of switching the speed on, the grinding wheel 4 moves, together with a cross sliding table 2, at about the same speed as the growing speed of the passive coat, and the surface of the workpiece W is machined while removing the passive coat by the grinding wheel 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrolytic multi-tasking machine capable of processing a workpiece with a low surface distortion and a high surface roughness.

[0002]

2. Description of the Related Art Conventionally, when a workpiece is machined, electrolytic grinding, electrolytic composite polishing, electrolytic machining or the like has been carried out. The purpose of electrolytic grinding is to improve machining efficiency. The range of the current density at which is not generated, that is, FIG.
As shown in (4), the electrolytic action is generated between the grindstone and the workpiece in the range of critical current density ρ or more, and the surface of the workpiece is melted in a large amount in a short time and is processed by the grindstone. Since the surface roughness of the workpiece is poor only by itself, the surface of the workpiece is machined in the final step when it is desired to machine the workpiece with good surface roughness.

Electrolytic composite polishing also repeats a series of cycles in which a passivation film is formed on the surface of a workpiece by an electrolytic action, and the passivation film is removed by a viscoelastic grindstone. In particular, in this electrolytic composite polishing, it is preferable that each abrasive grain of the grindstone uniformly contacts the surface of the workpiece with a relatively small pressing force. Is used, that is, a grindstone holding abrasive grains with a viscoelastic body is used.

The electrolytic processing is to dissolve and remove the surface of the workpiece by mere electrolysis.

[0005]

However, in the conventional electrolytic grinding, when the workpiece is machined with a high surface roughness as described above, the surface of the workpiece is machined in the final step. A large amount of machining strain due to machining remains on the workpiece, so that the workpiece cannot be machined in a state with less machining strain and with a high surface roughness.

Further, in the conventional electrolytic composite polishing, since a grindstone holding abrasive grains with a viscoelastic body is used, when such a grindstone has undulations generated on the surface of a workpiece, Elastic deformation along the undulation is unavoidable without scraping the top of the undulation, and the undulation remains or is amplified and becomes large, so there is no ability to modify the surface shape of the workpiece and It cannot be processed with good flatness.

On the other hand, in the conventional electrolytic machining, the surface of the work is melted and removed only by electrolysis, so that the ability to modify the surface shape of the work is improved as compared with machining by a grindstone. However, there is a problem that the workpiece cannot be machined with good flatness.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an electrolytic multi-tasking machine capable of processing a workpiece with a high surface roughness and a high flatness in a state where the processing strain is small. Especially.

[0009]

In order to achieve the above object, the present invention provides a grindstone of fixed abrasive grains which is arranged so as to face a work piece and has conductivity and which has conductivity, and the grindstone and the work piece. A cutting table to be relatively close to each other, a working liquid supplied to the gap between the grindstone and the workpiece, a power source in which the grindstone is connected to the cathode and the workpiece is connected to the anode,
To the same speed as the growth rate of the passivation film generated on the workpiece side by the electrolytic action generated between the grindstone and the workpiece,
A cutting speed switching means for switching the cutting speed of the cutting table is provided.

[0010]

According to the present invention, the grindstone of the fixed abrasive grains moves at a speed similar to the growth rate of the passivation film formed on the work side, while removing the passivation film, the work piece is removed. Process the surface of.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the electrolytic composite processing machine according to the present invention will be described below in detail with reference to FIGS.

In the electrolytic composite processing machine shown in FIG. 1, a grindstone shaft unit 1 is installed on a cutting table 2, and a grindstone shaft 3 of the grindstone shaft unit 1 is provided with a cup-shaped grindstone 4 at its tip. This grindstone 4 is a grindstone of so-called fixed abrasive grains having an abrasive grain held by a metallic material, and is arranged so that its end face 4a faces the surface of the workpiece W. There is.

On the other hand, the cutting table 2 has a cutting motor 5
When the whetstone spindle unit 1 is activated, the whetstone 4 is moved to the workpiece W.
Toward the surface side of the workpiece, that is, the grindstone 4 and the workpiece W
And are relatively close to each other.

Further, the working liquid is supplied to the gap between the grindstone 4 and the workpiece W, and the grindstone 4 is connected to the cathode 6a of the electrolysis power source 6, and the workpiece W Is connected to the anode 6b of the electrolysis power supply 6. In addition,
The workpiece W is arranged so as to be integrally fixed to the spindle of the spindle unit 7 via a chuck (not shown).

Further, in this electrolytic composite processing machine, a dimension measuring device 8, a cutting speed switching circuit 9 and an electrolytic current value switching circuit 10 are provided.
Is provided, and the dimension measuring device 8 is configured to measure the machining allowance of the workpiece W and output the measurement result to the cutting speed switching circuit 9 and the electrolytic current value switching circuit 10.

On the other hand, the cutting speed switching circuit 9 determines whether or not the work W is to be refined based on the measurement result from the dimension measuring device 8 and also determines that the work W is to be refined. In this case, the speed switching signal is set to the cutting speed setting circuit 1
Output to 1, is configured to switch the set value of the cutting speed setting circuit 11 to Seiken cutting speed V _1, and its fine Labs cutting speed V _1, the grinding wheel 3 and the workpiece W The growth rate is about the same as the growth rate (1 to 200 nm / sec) of the passivation film formed on the workpiece W side by the electrolytic action generated between them.

The electrolytic current value switching circuit 10 determines whether or not the work W is to be refined based on the measurement result from the dimension measuring device 8 and also determines that the work W is to be refined. In this case, by outputting a current value switching signal to the electrolysis power source 6, the range of the current density at which the passivation film can be generated, that is, the range below the critical current density ρ as shown in FIG. The electric current value of the electrolysis power source 6 is switched so that the electrolysis action occurs at mA / cm ^{2 to} 1 A / cm ² .

Next, the operation of the electrolytic composite processing machine configured as described above will be described with reference to FIG. In addition, the workpiece W
Is fixed integrally with the spindle of the spindle unit 7 via a chuck.

According to this electrolytic compound processing machine, the cutting table 2 is moved to a predetermined position immediately before the whetstone 4 and the workpiece W rotate in the directions of the arrows in the figure, and immediately before the whetstone 4 and the workpiece W contact each other. The workpiece W is moved toward the surface side of the workpiece W at the roughing cutting speed V ₂ , and the roughening of the workpiece W by the grindstone 4 is started. During such rough polishing, an electrolytic action is generated between the grindstone 4 and the workpiece W in the range of the current density at which the passivation film is not formed, that is, in the range of the critical current density ρ or more as shown in FIG. It is also possible to improve the processing efficiency by causing the surface of the workpiece W to be dissolved in a large amount in a short time and processing it with the grindstone 4.

Simultaneously with the above-mentioned rough grinding, the dimension measuring device 8 measures the present machining allowance of the workpiece W, and the measurement result is the cutting speed switching circuit 9 and the electrolytic current value switching circuit 10.
Is output to. At this time, in the cutting speed switching circuit 9 and the electrolytic current value switching circuit 10, it is determined based on the measurement result from the dimension measuring device 8 whether or not the precision polishing is performed. That is, when it is confirmed from the measurement results that the rough polishing has progressed to a dimension suitable for performing the precision polishing, it is determined that the precision polishing of the workpiece W is performed.

In this way, when it is judged that the work W is to be subjected to precision polishing, the electrolytic current value switching circuit 10 outputs a current value switching signal to the electrolysis power source 6 and the cutting speed switching circuit 9 also. The speed switching signal is output to the cutting speed setting circuit 11.

As a result, the current value of the electrolytic current value switching circuit 10 is switched so that the electrolysis action occurs within the range of the current density capable of forming the passivation film, and as a result, the grinding stone 4 and the work piece are machined through the working fluid. Electrolysis occurs between the objects W, and a passivation film is formed on the surface of the workpiece W. Further, the set value of the cutting speed setting circuit 11, that is, the rough cutting cutting speed V ₂ is switched to the precise cutting cutting speed V _1, and as a result, the cutting table 2 moves at the precise cutting cutting speed V ₁ . At the same time, the grindstone 4 moves at a fine-cutting cutting speed V ₁ , that is, at the same speed as the growth speed of the passivation film formed on the work side, and while removing the passivation film, the work W is removed. Process the surface of.

According to such processing, the work strain remaining on the work W is extremely small, and the work W has good surface roughness.
When the whetstone is machined and the surface of the workpiece W has undulations caused by pre-processing or the like, the grindstone 4 is not greatly deformed along the undulations and the top of the undulations is scraped off. Surface is processed as flat as possible.

Therefore, according to the electrolytic compound processing machine of the above-mentioned embodiment, a grindstone of fixed abrasive grains is used, and this grindstone has a fine cutting speed, that is, a growth rate of a passivation film formed on the workpiece side. Since the surface of the workpiece is machined while moving the same speed while removing the passivation film, the machining strain remaining on the workpiece is extremely small and the surface roughness of the workpiece is improved. That is, even if there is undulation on the surface of the workpiece due to pre-processing, the grindstone does not significantly deform along the undulation, and the top of the undulation is scraped off to make the surface of the workpiece as flat as possible. Since it is corrected to, the workpiece can be machined with good surface roughness and flatness with little machining distortion.

Further, in this electrolytic compound processing machine, before the surface of the workpiece is machined while the passivation film is removed while the grindstone moves at the fine cutting rate, the same grindstone is used in advance. Since the surface of the work piece is roughly ground, the work piece can be processed efficiently.

Moreover, according to this electrolytic compound processing machine, since the growth rate of the passivation film and the removal rate of the passivation film are equal, the removal of the passivation film is neither too much nor too little. Since the passivation film is removed in an appropriate amount, a series of cycles of removing the passivation film with a grindstone while forming the passivation film can be accurately repeated.

In the above embodiment, the cup-shaped grindstone 4 was used as the fixed-abrasive grindstone, but the grindstone is not limited to this type, and a cylindrical grindstone 12 as shown in FIG. 2 may be used. Well, when this cylindrical grindstone 12 is used, the outer peripheral surface of the cylindrical grindstone 12 and the surface of the workpiece W are arranged so as to face each other, and the cylindrical grindstone 12 rotates around its axis and the reciprocating table. It is arranged so as to be able to reciprocate left and right along the surface of the work W by the work 13, and the work W is rotated about its axis while the cutting table 2 causes the cylindrical grindstone 1 to move.
It is configured so that it can be moved toward the outer peripheral surface of 2, that is, relatively close to the cylindrical grindstone 12.

[0028]

In the electrolytic composite processing machine according to the present invention, a grindstone of fixed abrasive grains is used as described above, and this grindstone has a growth rate of the passivation film which is generated on the side of the workpiece. Since the surface of the workpiece is machined while moving the speed of removing the passivation film, the machining strain remaining on the workpiece is extremely small and the surface roughness of the workpiece is improved. Even if there are undulations on the surface of the workpiece due to pre-processing, the grindstone does not significantly deform along the undulations, and the top of the undulations is scraped off to make the surface of the workpiece as flat as possible. Therefore, the workpiece can be machined with good surface roughness and flatness in a state where the machining distortion is small.

[Brief description of drawings]

FIG. 1 is an explanatory view for explaining an embodiment of an electrolytic combined processing machine according to the present invention.

FIG. 2 is an explanatory view explaining another embodiment of the present invention.

FIG. 3 is an explanatory diagram illustrating a range of current density in which a passivation film is generated.

[Explanation of symbols]

 4 Grinding stone 2 Cutting table 6 Power supply 9 Cutting speed switching circuit W Workpiece

Claims (1)

[Claims] 1. A grindstone of fixed abrasive grains which is arranged so as to face a work piece and has conductivity, a cutting table which brings the grindstone and the work piece relatively close to each other, and the grindstone and the work piece. Generated in the workpiece side by the machining liquid supplied to the gap, the power source in which the grindstone is connected to the cathode and the workpiece is connected to the anode, and the electrolytic action generated between the grindstone and the workpiece. An electrolytic multi-tasking machine comprising: a cutting speed switching means for switching the cutting speed of the cutting table to a speed substantially equal to the growth speed of the passivation film.