JPH0729244B2 - Electromachining liquid - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention interposes between an electrode and a workpiece when performing electric discharge machining by performing intermittent electric discharge between the electrode and the workpiece. The present invention relates to an electromachining liquid.

(Prior Art) In electric discharge machining, an object is engraved, a hole is formed, or an object is carved by intermittent spark discharge in an insulating medium between a working electrode and a conductive workpiece. It is a technique of cutting an object. This technology has been widely used for various metal workings today, because it is not affected by the hardness of the object and it is expected to have a processing accuracy of surface roughness ± 0.2μm or less, which is close to a mirror finish. ing.

Conventionally, mineral oil (kerosene) has been mainly used as the above insulating medium. However, since this mineral oil is flammable, there is a risk of fire when performing continuous processing unmanned. Therefore, the use of pure water came to be tried recently. However, while water has a high processing speed, it has a drawback that it consumes the electrodes. Therefore, recently, addition of various molecular weight control substances to water has been studied, for example, ethylene glycol, propylene glycol, polyethylene glycol, glycols such as polyalkyl ethers or their derivatives, or nonionic substances such as higher alcohols, It has been proposed to add an anionic substance such as polyacrylic acid, acrylamide, guar gum or sodium alginate, or a cationic substance such as chitosan, polyacrylamide or methacrylic acid ester (see, for example, Japanese Patent Publication No. 59-4253).

However, even in this case, the electrode consumption ratio is reduced to only about 3% (see FIG. 2 of the above publication). However, in order to obtain sufficient processing accuracy in the carving process and the drilling process, it is absolutely necessary that the electrode wear rate be less than 1% at all. I am dissatisfied with any of them.

(Object of the Invention) The present invention provides an aqueous electromachining liquid that has an epoch-making electrode consumption rate and can maintain the rate at best at 1% or less even when continuously used for a long time. The purpose is.

(Means for Achieving the Purpose) As a result of energetic research on many new and known nonionic polymer substances, the present inventor has found that at least four substituted or unsubstituted oxyethylene groups are present in the molecule. It has been found that a water-soluble aliphatic ether compound containing is extremely suitable as a component of an aqueous electroprocessing liquid. That is, the present invention, as an essential component of the electromachining liquid, the general formula It is characterized by containing an alkoxy-substituted oxyethylene derivative represented by

Examples of the substituents R ₁ and R ₃ in the compound (I) include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group and secondary butyl group. The compound (I) actually used may be a single compound containing a single group or a mixture with a compound containing another type of group. Further, the substituent R ₂ is hydrogen,
It is selected from a methyl group and an ethyl group. Also for this substituent R ₂ , the compound (I) may be a single compound in use or a mixture of plural kinds of compounds.

Further general formula, The polymerization number n of the oligo- or poly-substituted oxyethylene group (excluding the case where n is 1) represented by is preferably within the range of 100 (average number) or less. When n exceeds 100, the viscosity of the aqueous solution increases, resulting in difficulty in working. In this connection, as examples of compound (I), for _{example; CH 3 OCH 2 CH 2 O} n CH 3 = 1~100 CH ₃ CH ₂ CH ₂ O (CH ₂ CH ₂ O) _n CH ₂ -CH = CH ₂ = 1 to 100 CH ₃ CH ₂ CH ₂ CH ₂ O (CH ₂ CH ₂ O) _n CH ₂ -CH = CH ₂ = 1-100, etc. can be mentioned.

In addition, in this invention, the compound which belongs to the above-mentioned compound (I) can be used individually or in combination as needed.

In order to prepare the processing liquid of the present invention, water is previously treated with an ion exchange resin so that its specific resistance is 10 ⁴ Ω · cm or more, and then an appropriate amount of the compound (I) is added and stirred. , Dissolve. The preferred concentration is 0.5 to 85%, but a small amount of rust preventive agent may be added at this time if necessary. In the above adjustment operation, the ion exchange resin treatment may be performed last.

(Examples) Hereinafter, embodiments of the present invention will be described with reference to Examples, but it goes without saying that the examples do not directly limit the inclusion and extension of the inventive idea.

Example 1 [Preparation of working fluid] After dissolving a compound belonging to the above-mentioned compound (I) in water, it was adjusted to show a specific resistance value of 2 × 10 ⁵ Ω · cm through an ion exchange resin to obtain a working fluid for testing. did.

[Compounds used] Shown in Table 1 below.

[Experimental conditions] Table 2 below shows.

[Results] As shown by the curve A in FIG. 1 to FIG. 3, the working fluid using each compound of A-1 to A-4 belonging to the compound (I) in the compound group of Table-1 has a working speed. It is known that, in any of the electrode wear rate and the durability, the results are superior to those using the control compounding parts C-1 to C-2. Example 2 An aqueous solution prepared by dissolving the compounds shown in Table 1 in pure water desalted with an ion exchange resin was used as a working fluid.
Wire cutting was performed under the following conditions.

Was carried out.

Model used: Sodick 330-w Machining electrode: Wire FKH φ0.2mm Workpiece: SKD-11 20mm thickness Machining conditions: Wire feed speed 5m / min Machining liquid resistance 3 × 10 ⁴ Ωcm Voltage 35V Current 10A The results are shown in FIG. 4. As shown in the figure, in the compound group of Table-1, the processing liquids using the compounds A-1 to A-4 belonging to the compound (I) were the control compounds C-1 to C-1. It can be seen that the processing speed is superior to that of the control solution using C-2.

(Effect) As described above, the electromachining liquid according to the present invention is superior not only to the electrode wear rate but also to the known water-based machining liquid not only in the electrode wear rate but also in the machining speed and durability. .

[Brief description of drawings]

1 to 3 are graphs comparing the working fluid of the present invention and the known working fluid with respect to the machining speed and the electrode consumption rate for die cutting, and FIG. 4 is the working fluid of the present invention with the known working fluid for wire cutting. 2 is a graph comparing the processing speeds. In the figure, the curve indicated by A (-○-) shows the case of using the compound of the present invention, and the curve indicated by C (-●-) shows the case of using the control compound.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shigeo Mori No. 1 at 35, Katsura Chiyohara-cho, Nishikyo-ku, Kyoto City, Kyoto Prefecture

Claims (2)

[Claims] 1. A water-soluble compound represented by the following general formula (I): An electromachining liquid which contains as an essential component. 2. The compound according to claim 1 is added in an amount of 0.5 to 85.
%, The electromachining liquid according to claim 1 which is an aqueous solution.