JPH06210517A - Deterioration measuring method of oily electric discharge machining liquid - Google Patents

Abstract

PURPOSE:To carryout accurately the measurement of the deterioration degree of an oily electric discharge machining liquid making to an oily electric discharge machining liquid containing tarlike substance transmit visible rays or infrared rays measuring the quantity of light-rays absorbed by transmission. CONSTITUTION:When the deterioration of an oily electric discharge machining liquid is measured, for example, laser rays of about 640-700nm wave length obtained from a light emission diode is radiated to the oily electric discharge machining liquid, the absorption quantity of laser rays increases in compliance, with the increase of trouble generation frequency in electric discharge machining. Accordingly, when the absorption of light quantity is being measured in lapse of time, the generation of trouble, that is, the state of deterioration can be known beforehand from the absorption of light quantity. As a result, a measuring device is made up of a container 20 in which the light emitting element 21 and a light receiving element 22 of laser rays are housed in their arrangement of facing each other, and by arranging this measuring device in an electric discharge machining tank, the absorption degree of the light quantity of the oily electric discharge machining liquid, that is, deterioration is measured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deterioration measuring method capable of measuring minute changes in an oil-based electric discharge machining fluid which causes problems in electric discharge machining. More specifically, the change in the oil-based electrical discharge machining fluid that causes troubles in electrical discharge machining such as large irregularities on the discharge surface or unstable discharge is specified,
And predictable degradation measurement methods.

[0002]

2. Description of the Related Art Machines, instruments or devices (hereinafter sometimes abbreviated as machines) have various types suitable for various purposes such as lubrication and energy transmission depending on the purpose of use of the machines. Oil is used.

Lubricating oil is one of the typical oils. Lubricating oils include, for example, engine oils, compressor oils, turbine oils and others. These are used by adding various additives to a base oil (oil which is a quantitative basis of various industrial oils) suitable for each application. The same applies to oils other than lubricating oil, for example, working oil or hydraulic oil. It is known that when the lubricating oil is used in a machine, it deteriorates in various modes depending on the type and usage of the machine, and if the deteriorated lubricating oil is continuously used, many troubles occur in the machine. There is. For example, some lubricating oils gradually deteriorate, but rotary compressor oil deteriorates suddenly one day without any sign during use and produces a large amount of sludge, which damages the equipment. To do. Therefore, the deterioration of the lubricating oil should be measured by the method of using the machine or by a precise method depending on the characteristics of the oil.

However, in general, deterioration is judged by visual judgment based on empirical rules and measurement of the total acid number of oil. The same applies to industrially used oils other than lubricating oils.

Although instrumental analysis is often used in studies of oil deterioration, it is only used as a complement to the judgment of deterioration in the oil actually used.

[0006] The total acid number of oil is used as a criterion for determining deterioration, and the total acid number indicates the number of milligrams of potassium hydroxide required to neutralize free fatty acids or acidic substances contained in oil. That's why.

That is, conventionally, the deterioration of the oil has been mainly captured by the cutting of the hydrocarbon which is a component of the oil and the oxidation of the cut hydrocarbon.

On the other hand, the oil-based electric discharge machining fluid is completely different in terms of use from other industrially used oils because it discharges tens of thousands of times per second in the fluid. And it is harsh.

Further, there is a peculiarity that various substances (typically, processing scraps) are generated in the liquid by the electric discharge and they can be affected by the electric discharge (for example, reaction).

However, in the oil-based electrical discharge machining fluid, the factors related to deterioration are complicated, and the mutual influence among many factors cannot be clarified. Therefore, deterioration is determined by the same method as other oils. That is the reality.

That is, the visual judgment based on the empirical rule,
This is a method based on the judgment by measuring the total acid value. The measurement of trace components by infrared spectroscopic analysis is only used to complement those judgments. In response to such a situation, one of the inventors of the present invention has observed that in many cases of industrial-scale electric discharge machining devices, the oil-based electric discharge was used in the measurement of total acid value and the measurement of trace components by infrared spectroscopy. It was clarified that the deterioration of the working fluid could not be clearly identified (see the 1st National Conference on Electromachining, published on November 19, 1991). One of the inventors of the present invention and his collaborators found that tar-like substances, even oil-based electrical discharge machining liquids, showed no change in the measurement of total acid number and trace components by infrared spectroscopy. It has been pointed out that there are phenomena such as being easily attached to a work piece, waviness and unevenness on the discharge surface becoming large, and the discharge becoming unstable and the processing speed becoming slow.

That is, it has been proposed that the deterioration of the oil-based electrical discharge machining fluid should be synonymous with the state in which such a phenomenon occurs.

However, as far as the inventor knows,
No industrially meaningful measuring method has been proposed that can identify the change in the oil-based electrical discharge machining fluid that causes such a phenomenon. In particular, regarding the deterioration of the oil-based electrical discharge machining fluid in which a conductive or semiconductive powder is dispersed, the effect on the degradation of the dispersed powder may be unknown, and such degradation of the oil-based electrical discharge machining fluid may occur. The method of measurement was also unknown.

[0014]

For the above reasons, the use of the oil-based electrical discharge machining liquid causes various problems due to deterioration, but none of them has been solved. Some of the problems are listed below.

First, in the case where a trouble occurs such that a tar-like substance adheres to the work piece during the electric discharge machining, or undulations and irregularities on the electric discharge surface become large, if the electric discharge machining is continued as it is, the work piece is processed. The surface roughness of the surface becomes large (becomes rough), and it becomes impossible to obtain the target precisely processed workpiece.

Secondly, even if such a trouble occurs during the electric discharge machining and the electric discharge machining is stopped, when the oil-based electric discharge machining fluid is replaced with a new oil-based electric discharge machining liquid, the workpiece undergoes a new thermal history, and the workpiece undergoes a new heat history. The processing accuracy of the work is reduced.

Thirdly, since it is impossible to predict the deterioration of the oil-based electric discharge machining fluid which causes such troubles in the electric discharge machining,
The electric discharge machining operation itself becomes unstable. Especially in electrical discharge machining, where there are many demands for continuous operation day and night,
A stable unmanned continuous operation day and night becomes difficult.

Despite such problems, little research has been conducted on the deterioration of the oil-based electrical discharge machining fluid.

Therefore, the present inventor examined the above-mentioned troubles occurring in electric discharge machining and changes in the oil-based electric discharge machining fluid, and found the correlation shown in FIG. 1 to obtain the present invention. That is, the present invention, firstly, in electrical discharge machining, accurately identifies deterioration of the oil-based electrical discharge machining fluid that causes phenomena such as large undulations and irregularities on the electrical discharge surface, unstable electrical discharge and slow machining speed. An object of the present invention is to provide a method for measuring deterioration of an oil-based electrical discharge machining fluid that can be used.

Secondly, according to the present invention, in the actual operation of the electric discharge machining apparatus, the deterioration of the oil discharge machining fluid can be predicted and the replacement time of the oil discharge machining fluid can be accurately determined. It also aims to provide the law.

A third object of the present invention is to provide a method for measuring deterioration of an oil-based electrical discharge machining fluid which can be applied to any type of oil-based electrical discharge machining fluid.

A fourth object of the present invention is to provide a method for measuring deterioration of an oil-based electrical discharge machining fluid, which can accurately determine the deterioration occurring in an oil-based electrical discharge machining fluid in which powder is dispersed.

A fifth object of the present invention is to provide a method for measuring deterioration of an oil-based electrical discharge machining fluid which enables simple and easy measurement even at a site where an actual electrical discharge machine is operated. And

Sixthly, the present invention provides a method for measuring deterioration of an oil-based electric discharge machining fluid, which makes it possible to control electric discharge machining so that troubles due to deterioration of the oil-based electric discharge machining fluid do not occur in the electric discharge machining. Also for the purpose.

[0025]

The method for measuring the deterioration of an oil-based electrical discharge machining liquid according to the present invention is a method of transmitting a visible ray or an infrared ray to an oil-based electrical discharge machining fluid containing a tar-like substance and absorbing the light rays by the transmission. The amount of light is measured, and thereby the deterioration of the oil-based electrical discharge machining fluid is measured. [Detailed Description of the Invention] The method for measuring the deterioration of an oil-based electrical discharge machining fluid according to the present invention is a method in which a laser beam from a light-emitting element is incident on and transmitted through an oil-based electrical discharge machining fluid, and absorption of the total amount of laser light mainly derived from tar-like substances This is a method for measuring the deterioration of the oil-based electric discharge machining fluid.

That is, in the deterioration measuring method according to the present invention, an oil-based electric discharge machining liquid containing a tar-like substance generated by electric discharge machining is directly measured, and a laser beam (particularly a laser beam of a light emitting diode) is transmitted therethrough. The absorption of the amount of light is measured.

These facts have been confirmed by the research conducted by the present inventor after the above-mentioned announcement (1st National Conference on Electromachining, November 19, 1991).
It was found that problems such as instability of discharge or reduction of machining speed were found to correlate with the absorption of the amount of laser beam transmitted through the oil-based electrical discharge machining fluid containing tar-like substances produced by electrical discharge machining. is there.

The correlation is specifically shown in FIG. In FIG. 1, the horizontal axis shows absorption of the amount of light of a laser beam that passes through an oil-based electric discharge machining liquid containing a tar-like substance generated by electric discharge machining. However, since the increase in the absorption of the amount of light progresses with the progress of electric discharge machining, it can be said that the horizontal axis also represents the state of progress of electric discharge machining.

Further, the position of zero on the horizontal axis represents a state in which the absorption of the light quantity at the start of discharge is zero.

On the horizontal axis, the amount of absorbed laser light increases as it goes to the right side, but it is shown that the above-mentioned trouble does not occur by electric discharge machining up to the position (x) on the horizontal axis.

The vertical axis represents the amount of tar-like substances produced, as shown by the line d in FIG. 1, and even between the position of zero on the horizontal axis and the position (x) on the horizontal axis, there is a gentle slope to the right. It becomes a line that rises to.

That is, when the production amount of the tar-like substance increases, the absorption amount of the laser beam also tends to increase.

The vertical axis represents the frequency of troubles caused by electric discharge machining. The position of zero (which is also the position of zero on the horizontal axis) represents the state where no trouble occurs.

The area enclosed by the diagonal lines by the lines a and b in FIG. 1 is the area where the trouble has occurred.

The line c is a line drawn so that the region surrounded by the diagonal lines by the lines a and b is divided into two parts.

However, in the actual measurement, the occurrence frequency of troubles varies. However, inductively, it becomes like a region surrounded by lines a and b. If it is difficult to find a region that spreads from one point (that is, the position of (x) on the horizontal axis) due to the large variation in the frequency of occurrence of trouble, the (x) on the horizontal axis is not a point. You may specify by the width.
The data in FIG. 1 was obtained by transmitting a laser beam having a wavelength of about 640 to 700 nm obtained from a light emitting diode through an oil-based electrical discharge machining liquid that is being electrical discharge machined. The electric discharge machining is performed under standard conditions.

According to FIG. 1, when the absorption amount of the laser beam of the light emitting diode becomes large and the production amount of the tar-like substance becomes to some extent (at the time point of (x) on the horizontal axis).
Then, it can be seen that a problem occurs in the electric discharge machining, and the problem is likely to occur thereafter.

Further, FIG. 1 shows that if the absorption of the light quantity is measured over time, the occurrence of trouble can be known in advance from the absorption of the light quantity. As described above, according to the present invention, it is possible to predict occurrence of a trouble in electric discharge machining (that is, deterioration of oil-based electric discharge machining liquid). As for the relationship between the total acid number of the oil-based electrical discharge machining fluid and FIG. 1, when the amount of tar-like substances produced is large,
The total acid number also increases. However, the case where both the production amount of the tar-like substance and the total acid value are large is a state in which troubles caused by electric discharge machining are very likely to occur.

However, on the right side of (x) on the horizontal axis,
Even if a trouble can be predicted from FIG. 1, the total acid value of the oil-based electrical discharge machining fluid may not change.

Therefore, the trouble of electric discharge machining which cannot be predicted by the conventional measurement of total acid value can be predicted by the method of the present invention. In the deterioration measuring method according to the present invention, an oil-based electrical discharge machining liquid containing a tar-like substance produced by electrical discharge machining is directly measured.

Moreover, in the present invention, the object is measured by an industrially convenient method of absorbing the light quantity of the laser beam. In the analysis of organic compounds, analysis of atoms or molecules of organic compounds from absorption of visible light, ultraviolet light, or infrared light is performed as a well-known analysis method. However, these analysis methods are based on the phenomenon that atoms or molecules absorb light of a constant wavelength (that is, constant energy) (ie, Grothus-Drap).
er's rule) is used. And usually,
Visible light, ultraviolet light or infrared light is transmitted through the solvent in which the organic compound is dissolved, the absorption spectrum of the transmitted light is measured with a spectrophotometer, and the relationship between the wavelength and the molar extinction coefficient is obtained. Specify the atom or molecule from the maximum absorption spectrum of. However, in the electric discharge machining, it is meaningless to measure the peak of the absorption spectrum under the present circumstances where the relationship between the troubles caused by the electric discharge machining and the atoms or molecules related thereto is unknown.

In the present invention, the object of measurement is essentially the tar-like substance that is generated in the oil-based electrical discharge machining fluid by electrical discharge machining. The tar-like substance is a black or brown viscous substance and is usually dispersed in the oil-based electric discharge machining liquid.

In the present specification, the term "tar-like substance" is used to mean that a black or brown viscous substance produced by electric discharge machining is an oil bituminous substance produced by thermal decomposition of an organic substance. This is because it is clear that there is a possibility that other things are included and that they are unique to electrical discharge machining. Oil-based electrical discharge machining fluid Any oil-based electrical discharge machining fluid to be measured in the present invention can be measured as long as it is an oil-based electrical discharge machining fluid that can be used for electrical discharge machining. Conventionally, it has been difficult to find an appropriate deterioration measurement method common to various oil-based electrical discharge machining fluids, because the trace amount of products produced by electrical discharge machining differ depending on the type and additive of the base oil of the oil-based electrical discharge machining fluid. It had been.

It will be solved by the present invention.

The base oil of the oil-based electric discharge machining liquid is generally mineral oil, polybutene, normal paraffin or alkylbenzene. Further, according to the measuring method of the present invention, it becomes possible to accurately measure the deterioration even if the type or amount of the additive added to those base oils as necessary is different.

The deterioration of the oil-based electric discharge machining liquid in which the powder is dispersed can also be measured by the present invention.

Oil-based electric discharge machining liquid in which powder is dispersed has come to be used because it has a function of remarkably smoothing the surface of a work piece. Regarding its deterioration measuring method, Not known at all.

The oil-based electrical discharge machining liquid in which the powder is dispersed includes both a liquid in which a conductive powder is dispersed and a liquid in which a semiconductive powder is dispersed, and both of them can measure deterioration according to the present invention. Will be possible.

Examples of conductive powders that can be used include the following.

Graphite, brass, tungsten, silver,
Metal powder such as cadmium, iridium, zinc, magnesium, tin, lead tungsten-silver alloy, copper and copper-tungsten alloy, and conductive powder such as graphite.

The following are examples of semiconductive powders that can be used.

Silicon is typical. There is no restriction on the application of the present invention, whether it is amorphous, polycrystalline or single crystalline silicon, or a mixture thereof.

The oil-based electrical discharge machining liquid in which the powder is dispersed is used for electrical discharge machining for finishing a workpiece on a highly smooth surface.
Since it is used for so-called finishing, it is indispensable to avoid the use of deteriorated oil-based electrical discharge machining liquid which causes undulations and irregularities on the discharge surface.
Moreover, conventionally, there has been no means for avoiding the use of such deteriorated oil-based electrical discharge machining fluid. However, according to the present invention,
It becomes possible to avoid the use of such deteriorated oil-based electrical discharge machining fluid in advance. That is, by using the deterioration measuring method of the present invention, it becomes possible to accurately and completely perform electric discharge machining using an oil-based electric discharge machining liquid in which powder is dispersed. Measuring Method In the present invention, a laser beam is irradiated onto an oil-based electrical discharge machining liquid produced by a tar-like substance to be transmitted, the light amount of the laser beam after the transmission is measured, and deterioration is measured from the amount of the laser beam absorbed during the transmission.

The absorbed light quantity depends on both the oil-based electric discharge machining liquid and the tar-like substance, and the relationship between the light quantity absorbed by both of them and the occurrence of trouble becomes clear from FIG.

The wavelength of the laser beam (that is, the energy of the laser beam) used in the measuring method of the present invention is, in principle, arbitrary as long as the relationship between the amount of light absorbed and the occurrence of troubles caused by electric discharge machining becomes clear. Wavelengths can be used.

In the absorption spectrum of the organic compound,
Generally, UV light of 200-400 nm, 400-
800 nm wavelength visible light and 2000-1600
Infrared light with a wavelength of 0 nm is often used.

That is, those wavelengths of ultraviolet rays and visible rays are in the energy range where the electrons of the organic compound excite, and the infrared rays of that wavelength are in the energy range where the molecules of the organic compound vibrate, This is because it is suitable for identifying atoms and molecules in an organic compound by a spectrum caused by excitation and vibration of molecules. However, in the measuring method of the present invention, the wavelength of the laser beam is
It has been found that those having a wavelength in a range extending over a part of the region above visible light and a region generally called near-infrared light, specifically those having a wavelength of about 640 to 950 nm are particularly suitable. Has been.

That is, with a laser beam having such a wavelength, the correlation shown in FIG. 1 becomes clearer.

A laser beam having a wavelength of about 640 to 950 nm can be obtained by a light emitting diode. Any light emitting diode can be used as long as it can emit visible light having a wavelength of about 640 to 700 nm or near infrared light having a wavelength of about 7,000 to 950 nm. It should be noted that the wavelength range of infrared rays does not have a clear division, and differs depending on the academic field. The term "infrared ray" of the present invention is used in a meaning including a range of wavelengths generally referred to as near infrared rays and a range of wavelengths generally referred to as far infrared rays. Then, the light amount of the laser beam that has passed through the oil-based electrical discharge machining liquid is received by the photoelectric sensor, converted into an electric signal, and output. It is suitable to use a highly sensitive photoelectric sensor.

As the photoelectric sensor, for example, a PIN silicon diode or the like can be used.

The deterioration measuring method according to the present invention has various modes.

The first aspect is the basic one. That is, a laser beam having a predetermined wavelength of about 640 to 950 nm and a predetermined amount of light is irradiated from an LED to an oil-based electric discharge machining liquid that is being electric discharge to be transmitted, and the amount of the laser beam after the transmission is measured. This is a method of continuously performing and observing the state of troubles (particularly the type and frequency of troubles) occurring in the electric discharge machining by ticking the electric discharge machining during that time.

From the results of observation, if a diagram similar to that shown in FIG. 1 was prepared, thereafter, by simply measuring the light amount of the laser beam that penetrates the oil-based electrical discharge machining liquid, an oil-based electrical discharge machining liquid in which troubles were likely to occur was produced. You can know in advance from the figure.

Further, if a diagram similar to FIG. 1 is obtained for individual oil-based electrical discharge machining liquids or individual electrical discharge machining conditions, laser beams of individual oily electrical discharge machining liquids or individual electrical discharge machining conditions The deterioration can be accurately known only by measuring the light amount.

The second mode is a method of forcibly causing a trouble in the electric discharge machining performed by the experimental apparatus, and then obtaining the same diagram as FIG. 1 in the same manner as in the first mode.

In FIG. 1, the horizontal axis is represented by the light quantity of the laser beam after passing, but the same may be said of the directly absorbed light quantity, and the light quantity is converted into an electric signal, It is the same even if it is displayed by replacing it with a number in a predetermined unit.

The present invention will be specifically described below based on examples, but the examples are illustrative and do not limit the present invention.

[0068]

【Example】

<Example 1> Example 1 is a method of measuring using a measuring device provided with a light emitting element and a light receiving element of a laser beam facing each other. FIG. 2 is a schematic diagram schematically showing the detection unit of the measuring device.

In FIG. 2, reference numeral 20 designates a container in which a light emitting element 21 and a light receiving element 22 for the laser beam are housed in a facing arrangement.

Since the container 20 is formed so that the oil-based electric discharge machining liquid can enter between the portion accommodating the light emitting element 21 and the portion accommodating the light receiving element 22, the measuring device is placed in an electric discharge machining tank. With this, the amount of light can be easily measured. The material of the container 20 itself is selected from a synthetic resin that has small energy attenuation when a laser beam of about 640 to 950 nm is transmitted. The light emitting element 21 and the light receiving element 22 are connected to a measuring device body (not shown) by lead wires (not shown) extending from the light emitting device 21 and the light receiving device 22, respectively, and are converted into numerical values by a control circuit provided in the measuring device body. . The light quantity converted into a numerical value is expressed as a light quantity per unit distance. <Example 2> In Example 2, a light emitting element and a light receiving element of a laser beam are provided side by side in a container, a reflecting plate is provided on a surface facing them, and a laser beam emitted from the light emitting element transmits an oil-based electrical discharge machining liquid. After that, the measurement is performed by using a detection unit that is reflected by a reflection plate, transmits the oil-based electrical discharge machining liquid again, and is then received by the light receiving element.

FIG. 3 is a schematic diagram schematically showing the detecting section.

In FIG. 3, reference numeral 30 denotes a container, which is composed of a portion 31 accommodating the light emitting element 21 and the light receiving element 22 and a reflecting plate 33. Contains the oil-based electrical discharge machining fluid to be measured. Container 30
The part through which the laser beam emitted from the light emitting element 21 passes and the part through which the laser beam entering the light receiving element 22 passes are formed of at least a material having a small attenuation of energy of the laser beam. Further, the reflecting plate 33 has a reflecting surface whose curvature is determined by the relationship between the arrangement of the light emitting elements and the light receiving elements, and as shown by the dotted line, the laser beam from the light emitting element is reflected and can be received by the light receiving element. It is like this. Even when using this detector, the amount of light is
It is expressed in terms of the amount of light per unit distance, but in addition to that, the data corrected by the efficiency at the time of reflection by the reflection plate 33 is obtained as actual data. <Example 3> Example 3 is a method for forcibly deteriorating the oil-based electrical discharge machining fluid in an experimental equipment for electrical discharge machining and using the data obtained there to determine the degradation of the oil-based electrical discharge machining fluid. . FIG. 4 is a schematic view showing a main part of the experimental apparatus in a partially enlarged manner. In FIG. 4, 41
Is a container accommodating a light emitting element, and the container 42 is provided so as to face the same and a light receiving element is accommodated therein. The light emitting element and the light receiving element housed therein are the same as those used in Examples 1 and 2. The distance between the surfaces of the containers 41, 42 facing each other may be small, for example about 0.5 m.
It may be about m. Experiments have shown that accurate and reproducible data can be obtained even at such a small distance. 43 and 44 are discharge electrodes, respectively, which are on an axis orthogonal to the axis of the arrangement of the containers 41 and 42 accommodating the light emitting element and the light receiving element, and between the both containers 41 and 42. Both discharge electrodes 4 in a state of enclosing the space of
3, 44 are provided so as to face each other. That is,
A cubic space area is formed by both the containers 41 and 42 and the discharge electrodes 43 and 44, and electric discharge is performed there. The light emitting element and the light receiving element are the same as those in the first and second embodiments.
The same one as used in is used.

The device shown in FIG. 4 is provided in a container (not shown), and an oil-based electrical discharge machining liquid is put in the container so that all the devices shown in FIG. do.

In the experiment, the discharge electrodes 43 and 44 discharge the oil-based electric discharge machining liquid in the cubic space region. The electric discharge is performed under the conditions adopted in standard electric discharge machining. Simultaneously with the start of the electric discharge, the light emitting element and the light receiving element housed in the containers 41 and 42 are operated to measure the absorption of the light amount of the laser beam passing through the oil-based electric discharge machining liquid.

The trouble caused by the discharge is caused by the electrodes 4 for both discharges.
The change occurring at 3, 44 is read from the discharge control circuit.

In this way, a diagram similar to that of FIG. 1 can be obtained.

[0077]

The object of the present invention is achieved by the deterioration measuring method of the present invention.

That is, according to the present invention, the deterioration of the oil-based electric discharge machining fluid that causes the phenomenon that the undulations on the discharge surface become large, the discharge becomes unstable and the machining speed becomes slow, etc., is simply measured by measuring the quantity of laser light. Can be identified by any means.

Since the deterioration of the oil-based electrical discharge machining fluid can be specified and can be predicted in advance, it becomes possible to accurately determine the replacement time of the oil-based electrical discharge machining fluid in the actual operation of the electrical discharge machining apparatus.

Since the method of the present invention can be applied to any type of oil-based electrical discharge machining fluid, it has great industrial utility.

According to the method of the present invention, it is possible to specify and predict deterioration of an oil-based electrical discharge machining liquid in which a powder is dispersed, which has not been provided with a means for specifying or predicting deterioration. In the method of the present invention, since the measuring means can be easily obtained industrially, it becomes possible to perform the measurement easily and easily even in the field where the actual electric discharge machine is operated. Further, by applying the method of the present invention, it becomes possible to easily control electric discharge machining so that troubles due to deterioration of the oil-based electric discharge machining liquid do not occur.

[Brief description of drawings]

FIG. 1 is a diagram showing a correlation between absorption of a light quantity of a laser beam and a trouble in electric discharge machining.

FIG. 2 is a schematic diagram of a detection unit of the measurement device.

FIG. 3 is a schematic diagram of a detection unit of the measurement device.

FIG. 4 is a partially enlarged view of the experimental device.

[Explanation of symbols]

 20 Container 21 Light-Emitting Element 22 Light-Receiving Element 30 Container 31 Stored Part 33 Reflector 41 Container 42 Container 43 Discharge Electrode 44 Discharge Electrode

Claims (2)

[Claims] 1. A visible ray or an infrared ray is transmitted through an oil-based electrical discharge machining fluid containing a tar-like substance, and the amount of light absorbed by the transmission is measured, thereby measuring the deterioration of the oil-based electrical discharge machining fluid. , Measuring method for deterioration of oil-based electrical discharge machining fluid. 2. A light having a wavelength of 640 nm to 700 nm is used as the visible light, and 700 nm to 95 is used as the infrared light.
The deterioration measuring method according to claim 1, wherein a light beam having a wavelength of 0 nm is used.