JPS62218021A - Electrolytic grinding work method - Google Patents

Abstract

PURPOSE:To attempt an improvement of grinding efficiency in electrolytic grinding work method applied to hard-to-grind materials by applying high frequency or pulse voltage between a conductive grinding stone and a work piece with electrolyte injected whereby moving the grinding stone for grinding. CONSTITUTION:Both electrodes of a power source 14 are connected with a grinding stone 1 and a conductive work piece 13 through a slip ring 5 and a grinding stone shaft whereby high frequency or pulse voltage is applied. Simultaneously, the grinding stone 1 is rotated or swung at high speed whereby electrolyte 6 is injected onto the grinding stone 1 and the surface to be worked through a nozzle 7 by means of a pump 12. Owing to this constitution, slight melt takes place over the surface of the work piece 13 due to electrodes and discharging, and simultaneously the molten portion is mechanically peeled off and removed by abrasive grains 4. As both electrical grinding and mechanical grinding are performed simultaneously on the work piece 13 by this electrolytic grinding work method, highly efficient grinding can be made possible. Moreover, electric discharging is useful to prevent grinding stones from being loaded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an improvement in an electrolytic grinding method applied to grinding or cutting difficult-to-cut materials.0 [Prior Art] Cemented carbide, cutting tools, etc. Electrolytic grinding, which uses electrical energy, is used as a method for grinding or cutting difficult-to-cut materials. Electrolytic grinding involves grinding an electrode (
A current is passed between the workpiece (graphite grindstone) and the workpiece to electrochemically corrode the workpiece.

It is processed by melting it.

[Problem that the invention seeks to solve]

This is an excellent method that can process difficult-to-process materials that are difficult to machine by mechanical grinding, much faster than mechanical grinding because it depends on the electrical and electrochemical properties of the workpiece and is unrelated to its mechanical properties. Although this is a grinding method, there are the following problems in processing.

(1) Since it is necessary to interpose an electrolytic solution between the grindstone and the workpiece, a clearance is required between the two. Therefore, the finished dimensional accuracy is much lower than that of mechanical grinding.
The ground surface is also rough.

(2) In order to obtain a high-precision product, it is necessary to perform final grinding using a mechanical grinding wheel in another processing device.

(3) When processing parts with high dimensional accuracy, it is not possible to take advantage of the sharpness of the grinding speed peculiar to electrolytic grinding.

[Means for solving problems]

The present invention was developed to solve the above-mentioned problems, and involves applying a high frequency voltage or pulse voltage between a conductive grindstone and a conductive processing material, and inserting a polishing tool into the grindstone shaft. The present invention provides an electrolytic grinding method in which a pre-processed material portion is ground by giving a rotating or oscillating motion to a grindstone while spraying an electrolytic solution.

[Effect]

The reason why the voltage applied in the present invention is high frequency or pulsed is to superimpose the electric discharge effect on the conventional electrolytic and mechanical grinding. This prevents clogging of the grinding wheel due to electric discharge, and the dressing effect of electric discharge allows constant grinding. Grinding efficiency is improved because it can be ground with sharp abrasive grains.

〔Example〕

An embodiment of the present invention will be described with reference to FIGS. 1 and 2. 1st
The figure is a cross-sectional view of an example of a grinding wheel. (1) is the entire grinding wheel, (2) is the shaft hole, (3) is metal bond or cast iron bond, and (4) is the abrasive grains made of diamond, horacin (CBN), etc.
) etc.

Figure 2 is a block diagram of an embodiment of the entire device, (5) is a slip ring, (6) is an electrolyte, and NaNO3r NaC1
1 to 2 multi-aqueous solutions such as mKNO, (7) is a nozzle, (8
) is a tool drive source, (9) is an insulator, Oll is a robot hand dll) is a grindstone shaft to which the grindstone (1) is attached. 0
A pump 21 is used to pump the electrolyte into the nozzle (7).

(13 is the workpiece, 0 is the power supply. In addition, the grinding wheel shaft (
11) and the tool drive power source are electrically insulated via an insulator (9), so that no electricity leaks toward the robot hand OO.

Next, we will discuss the operation. Both poles of the power source (14) are connected to the grinding wheel (1) and the conductive workpiece α via the slip ring (5) and the grinding wheel shaft 0υ, and a high frequency or pulse voltage is applied.At the same time, the grinding wheel (1) The electrolytic solution (6) is spouted through the nozzle (7) toward the grinding wheel (1) and the machining surface by rotating or shaking at high speed.The surface of the workpiece f13 is exposed to electrolysis and discharge. The dissolution progresses slightly, and at the same time, the magnetic grains (4) mechanically peel off and remove this melted part.The electric discharge not only contributes to the dissolution of the surface of the workpiece, but also prevents clogging of the grindstone. It also contributes to the prevention and abrasive dressing effect.

As mentioned above, on the workpiece (13), air grinding and mechanical grinding are performed at the same time, making extremely efficient grinding possible. υ, O capable of polishing to a trowel surface finish In the examples, power supplies with values in the range shown in Table 1 were used as power supplies applied to the present invention.

Table 1 In the above description, the case where the grindstone according to the present invention is attached to the grindstone shaft of a robot is shown, but it may be attached to other grindstone shafts. In addition, as described above about rotating or oscillating grindstones for grinding and polishing, abrasive grains (2000-φ8000) such as alumina, silicon carbide, or silicon nitride are included in the electrolytic solution and are sprayed between the grindstone and the processing surface. It's okay.

〔Effect of the invention〕

The following effects were obtained by the present invention.

(1) Since electrical (electrolytic/discharge) grinding and mechanical grinding are performed at high speed, the effects of both grinding occur synergistically, improving grinding efficiency and reducing power consumption.

(2) Even if there are strict requirements for finished dimensions and surface accuracy, there is no need to perform separate mechanical grinding in the next process. (3) The nine finished surfaces can be made smoother than by mechanical grinding alone. I can do that.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the grindstone, and FIG. 2 is a configuration diagram of the apparatus of the present invention. In the figure, (1) is a grinding wheel, (2) is a shaft hole, (3) is a metal bond or cast iron bond, (4) is an abrasive grain, (5) is a slip ring, (6) is an electrolyte, (7) is the nozzle, (8
) is the tool drive source, (9) is the insulator, (1 (l is the robot hand, α1) is the transmission, σ2 is the slip ring, O is the workpiece, and <14 is the source. Same symbols in the figure indicates the same or equivalent parts. Agent: Patent Attorney Masaru Sato

Claims (2)

[Claims] (1) Applying a high frequency voltage or pulse voltage between the conductive grinding wheel and the conductive processing material, inserting a polishing tool into the grinding wheel shaft and spraying electrolyte while giving the grinding wheel a rotating or oscillating motion; An electrolytic grinding method characterized by grinding the material to be processed. (2) The electrolytic grinding method according to claim 1, characterized in that the material to be processed is ground by spraying a conductive electrolyte containing abrasive grains onto the side surface of a non-conductive grindstone.