JP2012068048A - Device for monitoring lubricating oil deterioration - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for monitoring lubricating oil deterioration which is highly accurate, allows simple measurement, and achieves cost reduction for a wide range of oil types and a wide use environment.SOLUTION: A monitor device transmits a visible light beam from a single light source 3 through lubricating oil 1, and converts the visible light beam into an electric signal with a single light reception element 5 to detect the deterioration of the lubricating oil. A glass or resin filter 4 which has been coated for obtaining transmitted rays of light having a prescribed central wavelength and a half-value width is arranged between the light source 3 and the light reception element 5. Thus, it is possible to measure the transmitted rays of light with the width of the wavelength and accurately determine the degree of deterioration of the lubricating oil. That is, even when there is any variations in oil type and deterioration condition, the transmitted rays of light can be measured as a value that averages those variations. Also, it is possible to measure the transmitted rays of light with the single light source 3 and the single light reception element 5, and adopting a coating technology for the filter 4 enables less expensive manufacture of the device.

Description

  The present invention relates to a lubricant deterioration monitoring device. More specifically, the present invention relates to an apparatus for optimizing the light transmitted through the lubricating oil so as to best determine the degree of deterioration of any lubricating oil and determining the degree of deterioration of the lubricating oil by detecting the light.

  To accurately and continuously monitor the degree of deterioration of lubricating oil used in various equipment, various engines, machine drive parts, such as automotive lubricating oil and industrial lubricating oil, it is necessary to replace the lubricating oil when necessary This makes it possible to change the lubricant systematically. This not only saves the resources of the lubricating oil, but also extends the machine life.

  When determining the degree of deterioration of lubricating oil, it is generally performed by collecting the lubricating oil in use and measuring various physical properties such as color, viscosity, acid value, and amount of impurities in another laboratory. . In these methods, it is possible to comprehensively determine the degree of deterioration of the lubricating oil, but since it takes a lot of time and manpower, it is currently performed only in industrially important devices or expensive devices. It is. On the other hand, the fact is that such measures are not taken for many machines, including automobiles that exist in general, and many of these machines deteriorate according to driving time and mileage based on past experience. The current situation is that the lubricating oil is exchanged by assuming the situation or by simple visual inspection.

  Among the many deterioration monitors, apparatuses that are most likely to achieve both accuracy and price include a method by measuring transmitted light and a method by measuring electrical characteristics. Other methods are expensive or have problems with accuracy. The method based on electrical characteristics is very attractive because the structure of the device is simple and the cost can be kept low. However, this method has a problem that the measurement value varies depending on the measurement environment, and has a drawback that the change in the measurement value from the initial use to the middle period is small for industrial lubricating oil.

  On the other hand, the color determination method using light is characterized in that the color change of the lubricating oil always changes little by little with the use time, and the measurement value itself is very accurate. A simple apparatus is commercially available that uses this method to measure the transmittance of visible light to determine deterioration. However, with this simple method, even if the transmittance changes during the use of the lubricating oil, the deterioration degree and the transmittance are not in a linear relationship depending on the type of the lubricating oil, so the determination of the deterioration degree can be uniquely determined. Has the disadvantage of not.

  As a countermeasure against the difference in coloring tendency depending on the type of lubricating oil, a method of measuring transmitted light separately for RGB is known (see, for example, Patent Document 1). However, in this method, since the deterioration pattern differs depending on the type of lubricating oil, it is necessary to deal with each oil type, and it is difficult to determine a general-purpose deterioration degree. In this way, when the visible region is measured by dividing it into monochromatic light, it is necessary to select it or calculate it with an appropriate formula. Moreover, it becomes information only about the wavelength of the selected light, and it is assumed that it is difficult to cope with many types of lubricants or usage conditions. In addition, in order to measure transmitted light separately for RGB, it is necessary to use three types of RGB light emitting elements and one light receiving element, or one light source and three types of RGB light receiving elements.

  Further, the deterioration of the lubricating oil is determined from one of the tristimulus values of transmitted light and the chromaticity coordinates x and y obtained from the tristimulus values and constants A, B, C and D set in advance according to the type of the lubricating oil. There is known a method of obtaining a judgment score by calculation. (For example, see Patent Document 2). However, in this method, since it is necessary to obtain four constants for each oil type in advance, there remains a problem in versatility. Further, since three sensors are required, there is a problem that the cost becomes high.

  Furthermore, there is known an apparatus that uses at least two types of monochromatic light sources having different wavelengths and determines the degree of oil degradation based on the difference in light absorption loss between the two wavelengths (see, for example, Patent Document 3). However, in this method, since the optimal monochromatic light is different for each oil type, there remains a problem in reliability in dealing with many oil types.

Japanese Patent Laid-Open No. 06-034541 Japanese Patent Laid-Open No. 05-223729 Japanese Patent Laid-Open No. 11-235097

  As described above, conventional lubricant deterioration monitoring devices include a method based on absorption of transmitted light or light of a specific wavelength, a method based on absorption of infrared light or ultraviolet light, electrical characteristics such as capacitance, electrical resistance, dielectric constant, or electrodes. Many methods have been proposed, such as a method based on electromotive force measurement, a method based on physical properties such as viscosity or density, a particle counter, or a method of measuring insoluble matter from light transmission. However, none of them has been widely used due to reasons such as a problem in accuracy and reproducibility as an index for determining deterioration, or even if there is no problem, the device is expensive. In order to be applied to many machines, both improvement in accuracy as an index for determining deterioration and low price have been required.

  The object of the present invention is to solve such problems, and is highly accurate with respect to a wide range of oil types and a wide use environment, and can reduce costs and enable simple measurement. It is an object of the present invention to provide a lubricating oil deterioration monitoring device that can be used.

  Here, as a result of intensive studies, the present inventors have found that the deterioration of the lubricating oil can be grasped more accurately by measuring transmitted light having a specific wavelength width instead of monochromatic light. Further, the present inventors have found that the setting of a specific wavelength width can be easily and inexpensively achieved by using a glass or resin filter provided with a single or a plurality of coatings. In other words, when adjusting the wavelength width by coating glass or resin, the amount of transmitted light can be adjusted freely by setting the coating film freely compared to pasting existing filters. Therefore, high performance can be expected. In addition, since it is not necessary to attach several types of filters to glass or the like, the number of parts can be reduced, leading to a reduction in thickness, and as a result, downsizing. This also leads to a reduction in production costs. In addition, variations between products due to errors in pasting can be reduced. Thus, the present inventors have found various merits by forming a filter by coating glass or resin, and have reached the present invention.

  Therefore, the lubricating oil deterioration monitoring device according to the present invention transmits visible light generated from a single light source to the lubricating oil, receives the light with a single light receiving element, and converts it into an electrical signal to detect the deterioration of the lubricating oil. It is a device, and a glass or resin filter with a single or plural coatings is provided between a light source and a light receiving element to obtain transmitted light having a predetermined center wavelength and half width. Features.

  According to this lubricant deterioration monitoring device, a filter made of glass or resin having a single or a plurality of coatings for obtaining transmitted light having a predetermined center wavelength and half width between a light source and a light receiving element. Is arranged. Therefore, the measurement can be performed with a wavelength range, and the degree of deterioration of the lubricating oil can be accurately grasped. That is, by measuring with a wavelength range instead of monochromatic light, it is possible to measure the transmitted light as a value obtained by averaging the differences even if there are differences in the oil type and the deterioration state. Furthermore, since the required members are only a light source, a coated filter, and a light receiving element, the apparatus itself can be made extremely small and measurement can be performed easily. In addition, if there is a single light source such as a halogen lamp and a single light receiving element, the deterioration of the lubricating oil can be measured, so that the device can be manufactured at a lower cost and installed in more machines. become. In particular, since a filter is formed by coating glass or resin, a desired filter can be obtained easily and inexpensively. As described above, it is possible to achieve high accuracy with respect to a wide range of oil types and a wide use environment, reduce costs, and enable simple measurement.

  Further, in the lubricant deterioration monitoring apparatus according to the present invention, by applying a plurality of coatings, a plurality of wavelengths of the most appropriate transmitted light are selected, and the intensity of each wavelength is adjusted to monitor the deterioration of the lubricant. The most effective light can be obtained. The intensity of the transmitted light amount is adjusted by determining the intensity and the half-value width of the center wavelength of the transmitted light.

  In the lubricant deterioration monitor according to the present invention, specifically, visible light generated from a single light source is transmitted through the lubricant between the light source and the light receiving element, and is received by the single light receiving element. The device detects the deterioration of the lubricating oil by changing it into an electrical signal, and by applying a single or a plurality of coatings between the light source and the light receiving element, transmitted light having a predetermined center wavelength and a half width is obtained. A glass or resin filter is obtained for obtaining. In addition, the filter can obtain transmitted light having a center wavelength of 500 nm or more and less than 600 nm, a half width of 30 nm or more and less than 120 nm, and a whole wavelength range to be measured of 350 nm or more and less than 750 nm. The filter has a first transmitted light having a center wavelength of 400 nm or more and less than 500 nm and a half width of 30 nm or more and less than 100 nm, and a first transmitted light having a center wavelength of 500 nm or more and less than 575 nm and a half width of 30 nm or more and less than 100 nm. It is possible to obtain transmitted light such that the transmission ratio of the first transmitted light and the second transmitted light is 0 to 80% and 20 to 100%, respectively. The filter has a first transmitted light having a center wavelength of 400 nm or more and less than 500 nm and a half width of 30 nm or more and less than 100 nm, and a first transmitted light having a center wavelength of 500 nm or more and less than 575 nm and a half width of 30 nm or more and less than 100 nm. 2 transmitted light and a third transmitted light having a center wavelength in the visible range of 575 nm or more and less than 650 nm and a half width of 30 nm or more and less than 100 nm, the first transmitted light, the second transmitted light, and the third transmitted light Transmitted light can be obtained such that the transmission ratio of transmitted light is 0 to 80%, 20 to 100%, and 0 to 60%, respectively. Moreover, it is possible to use a condensing lens as glass or resin which performs the coating arrange | positioned between a light source and a light receiving element. The filter can also serve as a filter that blocks ultraviolet and infrared rays.

  ADVANTAGE OF THE INVENTION According to this invention, while being highly accurate with respect to a wide kind of oil and a wide use environment, cost can be reduced and simple measurement can be performed.

It is a figure which shows the structure of the lubricating oil deterioration monitoring apparatus which concerns on embodiment of this invention. It is a diagram which shows the result of Experimental example 1. FIG. It is a diagram which shows the result of Experimental example 2. FIG. It is a diagram which shows the result of Experimental example 3.

  Hereinafter, a preferred embodiment of a lubricant deterioration monitoring device according to the present invention will be described in detail with reference to the drawings.

  First, the configuration of the lubricant deterioration monitoring device 100 according to the embodiment of the present invention will be described. FIG. 1 is a diagram showing a configuration of a lubricant deterioration monitoring apparatus 100 according to an embodiment of the present invention. As shown in FIG. 1, the lubricant deterioration monitoring apparatus 100 is provided with a single light source 3 that irradiates the lubricant 1 to be inspected with visible light and a coating that allows the visible light transmitted through the lubricant 1 to pass through. Glass or resin filter 4, a single light receiving element 5 that receives and detects visible light transmitted through the lubricating oil 1 and filter 4, and an ADC / that processes an electrical signal output from the light receiving element 5 The MPU 6 includes a display 7 that displays data processed by the ADC / MPU 6 and a personal computer 8 that processes the data. The lubricating oil 1 is stored in a measurement location 2 such as a tank. In actual measurement, the light source 3, the filter 4, and the light receiving element 5 are immersed in the lubricating oil 1 as a measurement unit 10. However, the measurement may be performed by filling the sample cell with the lubricating oil 1 and placing the sample cell between the light source 3 and the filter 4.

  As the lubricating oil 1, various kinds of lubricating oils used for various devices such as automobile lubricating oil and industrial lubricating oil, various engines, driving parts of each machine, and the like can be applied. Multipurpose oil, hydraulic working oil, industrial general purpose oil, etc. can be measured.

  The light source 3 is composed of a single light source that emits visible light. The light source 3 is composed of one capable of continuous projection such as a tungsten lamp or a halogen lamp, or one capable of instantaneous projection such as a pulsed xenon lamp. Has been. The light source 3 may be either a continuous projection type or an instantaneous projection, and the wavelength is not limited. In addition, a white LED can be used as the light source 3. The light receiving element 5 has a function of receiving light irradiated from the light source 3 and transmitted through the lubricating oil 1 and the filter 4, converting it into a voltage, and outputting the voltage to the ADC / MPU 6. This light receiving element 5 is composed of a single element, and any commercially available photodiode can be used as an optical sensor.

  The ADC / MPU 6 includes an A / D converter for A / D converting the signal input from the light receiving element 5 and a microprocessor (MPU) for performing arithmetic processing. There are square root processing, cubic root processing, logarithmic processing, etc. as the arithmetic processing by the microprocessor. By performing these arithmetic processing, it is possible to improve the measurement sensitivity of the lubricating oil that is highly colored and darkly colored. It becomes. The calculation result by the microprocessor is output to the display 7 and the personal computer 8. Note that the A / D converted signal may be directly output to the display 7 and the personal computer 8.

  The measurement by the lubricant deterioration monitoring device 100 is started by an operation that simply turns on the power switch of the light source 3, the light receiving element 5, the A / D converter and display 7 and the personal computer 8. It is desirable to read the data into the personal computer 8 and plot the change over time. When the measured value is about 20% to 30% of the new oil, it can be judged as the standard for replacement of the lubricating oil. It is desirable to make a comparison with physical and chemical properties.

  In addition, the lubricant deterioration monitoring device 100 of the present invention can be made extremely small because the members necessary for the measurement unit 10 are only the light source 3, the filter 4, and the light receiving element 5. Since this measurement unit has simple constituent members, the sensor portion of the light receiving element 5 can have a diameter of 3 mm to 15 mm. As a result, the measurement unit 10 can be attached to every part of the machine such as a pipe, a tank, a cooler, and an actuator. A glass fiber (referred to as GF1) heading from the light source 3 to the filter 4 and a glass fiber (referred to as GF2) disposed on the light source 3 side so that one end thereof faces the end of the glass fiber GF1 and attached to the filter 4 ) And the optical path may be connected by each glass fiber. The light from the light source 3 is guided to the filter 4 and the light receiving element 5 by these glass fibers. The measurement can be performed by filling the lubricating oil 1 in a case including the light source 3, the glass fiber GF 1, the glass fiber GF 2, the filter 4, and the light receiving element 5. Alternatively, the measurement may be carried out by filling the lubricating oil 1 in a case including a part of the glass fiber GF1, the glass fiber GF2, the filter 4, and the light receiving element 5. Alternatively, the measurement may be performed by filling the lubricating oil 1 in a case including a part of the glass fiber GF1, the glass fiber GF2, and a part of the filter 4. Furthermore, the measurement may be performed by filling the lubricating oil 1 in a case including only a part of the glass fiber GF1 and only a part of the glass fiber GF2. In this case, only the glass fiber is immersed in the lubricating oil 1. Each case can guide light between the light source 3, the filter 4, and the light receiving element 5 with each glass fiber.

  In measurement, the measurement place 2 where the measurement unit 10 of the lubricant deterioration monitoring apparatus 100 according to the present embodiment is installed may be any place that touches the lubricant 1 such as a lubricant tank, an oil pan, or a pipe of a machine. Further, it may be placed in a place where it does not come into contact with the lubricating oil 1 at normal times and inserted into a tank or the like every time measurement is performed. In addition, although it is necessary to devise in terms of equipment, it is also possible to perform measurement by keeping the lubricant 1 out of contact during normal times and introducing the lubricant 1 during measurement. By adopting such a configuration, the device can be prevented from being contaminated by the lubricating oil 1.

  If the measurement unit 10 of the lubricant deterioration monitoring device 100 is immersed in the lubricant 1 for several years, dirt of the lubricant 1 may adhere to the sensor part of the light receiving element 5 of the measurement unit 10. It is necessary to wipe off the dirt of the lubricating oil 1. Various methods can be considered for wiping off the dirt. If a simple wiper is installed, automatic wiping is possible, and it is conceivable to periodically replace only dirty parts. Alternatively, it is possible to electrically cancel the dirt once taken out into the air.

  Next, the filter 4 of the lubricant deterioration monitoring device 100 according to this embodiment will be described in detail. The filter 4 is constituted by a glass filter or a resin filter in which a single or a plurality of coatings are applied between the light source 3 and the light receiving element 5 in order to obtain transmitted light having a predetermined center wavelength and a half width. Is done. The production method of the coating film in the present embodiment is manufactured using a normal vacuum deposition method, a sputtering method, and a vapor phase growth method. The vacuum deposition method is manufactured using an electron beam method (EB method), an ion assist deposition method (IAD method), or the like. As the coating material, a metal, a semiconductor material, or a dielectric material (metal oxide, fluoride, etc.) can be generally used. The transmission wavelength is selected by selecting a coating material, and the amount of transmitted light is adjusted by the thickness of the coating film. In addition, since multilayer coating is possible, it is possible to obtain transmitted light having a necessary center wavelength, half width, and intensity on a single glass or resin. It is also possible to adjust the amount of transmitted light by combining light of different wavelengths.

  The filter 4 can achieve its purpose even if glass or resin is coated so that it has a single wavelength of transmitted light with a certain half width, but the center of 1 to 3 has a suitable half width. By applying the coating so as to obtain transmitted light having a wavelength, the object can be better achieved.

  When the objective is to be achieved by the transmitted light of one central wavelength, the central wavelength is 500 nm or more and less than 600 nm, the half width is 30 nm or more and less than 120 nm, and the entire wavelength range to be measured is 350 nm or more and less than 750 nm. This is accomplished by applying a single or multiple layer coating to glass or resin.

  In the case of transmitted light having two central wavelengths, the first transmitted light having a center wavelength of 400 nm or more and less than 500 nm and a half width of 30 nm or more and less than 100 nm, the center wavelength of 500 nm or more and less than 575 nm, and a half value width By having a second transmitted light of 30 nm or more and less than 100 nm, and applying a plurality of layers of coating so that the transmission ratio of the first transmitted light and the second transmitted light is 0 to 80% and 20 to 100%, respectively. The objective is achieved. It adjusts so that desired 1st transmitted light and 2nd transmitted light can be obtained by coating several times on one glass or resin.

  In the case of transmitted light having three central wavelengths, the first transmitted light having a center wavelength of 400 nm to less than 500 nm and a half width of 30 nm to less than 100 nm, the center wavelength of 500 nm to less than 575 nm, and a half width Having a second transmitted light of 30 nm or more and less than 100 nm and a third transmitted light having a center wavelength in the visible region of 575 nm or more and less than 650 nm and a half-value width of 30 nm or more and less than 100 nm. The object is achieved by applying a plurality of coatings so that the transmission ratios of the two transmitted light and the third transmitted light are 0 to 80%, 20 to 100%, and 0 to 60%, respectively. This transmission ratio is preferably 0 to 20%, 40 to 80%, 20 to 60%, and more preferably 0 to 10%, 40 to 60%, and 40 to 60%. It adjusts so that desired 1st transmitted light, 2nd transmitted light, and 3rd transmitted light can be obtained by coating several times on one glass or resin.

  In the filter 4 arranged between the light source 3 and the light receiving element 5, a condensing lens can be used as glass or resin to be coated. Since the light emitted from the glass fiber is not laser light, it may spread slightly when passing through the lubricating oil 1. Therefore, by using a condensing lens as the glass or resin in the filter 4, such spread of light can be prevented. The filter 4 may serve as a filter that blocks ultraviolet rays and infrared rays. Since ultraviolet rays and infrared rays become noise, by blocking these, it becomes possible to select only light necessary for measuring the degree of deterioration, and the sensitivity is improved. The position of the filter 4 is not particularly limited and may be on the optical path, and may be before or after passing through the lubricating oil 1.

  Next, the operation and effect of the lubricant deterioration monitoring device 100 according to the embodiment of the present invention will be described.

  First, as a result of intensive research, the inventors have been able to more accurately grasp the deterioration of the lubricating oil by measuring transmitted light having a specific wavelength width instead of monochromatic light, and having a specific wavelength width. It was found that this setting can be easily achieved by arranging a glass or resin filter with coating.

  Furthermore, the present inventors have found that the reason why the deterioration of the lubricating oil can be grasped more accurately by measuring transmitted light having a specific wavelength width is as follows. The visible light transmittance of the lubricating oil is small on the short wavelength side and large on the long wavelength side. Further, the degree of decrease in the transmittance accompanying the deterioration of the lubricating oil tends to be large on the short wavelength side and small on the long wavelength side. For this reason, when measuring over the entire visible range, information on the long wavelength side, which has a large transmittance and a small change, is mainly used, and therefore the degree of change in the light transmittance accompanying the deterioration of the lubricating oil becomes small. .

  According to the lubricating oil deterioration monitoring device 100 according to the embodiment of the present invention derived in view of the above viewpoint, since the light in the visible range is divided and measured with a wavelength range, The degree of deterioration can be accurately grasped. That is, by measuring with a wavelength range instead of monochromatic light, it is possible to measure the transmitted light as a value obtained by averaging the differences even if there are differences in the oil type and the deterioration state. Further, in the lubricant deterioration monitoring apparatus 100 according to the present embodiment, light having a wavelength near the center of the visible range is the main target of measurement. This is because the transmittance on the short wavelength side is small in addition to the fact that the degree of change is large, so the transmittance may reach zero at the early stage of deterioration, and the change in transmittance is too small on the long wavelength side. This is because the change detection accuracy is low at the early stage of deterioration of the lubricating oil. Therefore, the lubricant deterioration monitoring device 100 according to the present embodiment can perform measurement with high accuracy even if there is a difference in deterioration state due to a difference in oil type or use environment.

  Furthermore, since the lubricant deterioration monitoring apparatus 100 according to the embodiment of the present invention includes only the light source 3, the filter 4, and the light receiving element 5 other than the ADC / MPU 6, the display 7, and the personal computer 8, It can be made extremely small and can be easily measured. Further, if a single light source such as a halogen lamp or a white LED is used as the light source 3 and a single sensor is used as the light receiving element 5, the deterioration of the lubricating oil can be measured, so that the apparatus can be manufactured at a lower cost. At the same time, installation on more machines becomes possible. As described above, it is possible to achieve high accuracy with respect to a wide range of oil types and a wide use environment, reduce costs, and enable simple measurement.

  The wavelength range to be measured may be only near the center, but by combining light with a wide wavelength range, it can be applied to more oil types and degradation conditions. Two or more wavelength ranges can be measured by applying a plurality of coatings, and a filter made of glass or resin that has been coated to obtain transmitted light having a plurality of center wavelengths with half-widths suitable for each. This is possible by using 4.

  Further, in the lubricant deterioration monitoring apparatus 100 according to the embodiment of the present invention, the glass or resin filter that is coated so as to obtain transmitted light having a plurality of center wavelengths having half widths suitable for each is visible light. It is arranged on the optical path. As a result, light that is more suitable for monitoring the deterioration of the lubricating oil can be received by the single light receiving element 5, so that an arithmetic circuit can be dispensed with. Further, by transmitting transmitted light having a plurality of center wavelengths and having a half-value width suitable for each in a balanced manner, accuracy can be further improved and versatility can be enhanced.

  Furthermore, when adjusting the wavelength width by coating glass or resin, the amount of transmitted light can be adjusted freely by setting the coating film freely compared to pasting existing filters together. Therefore, high performance of the filter 4 can be achieved. Moreover, since the operation | work which affixes several types of filters on glass etc. becomes unnecessary, it becomes possible to reduce a number of parts, and it leads to thickness reduction of the filter 4, As a result, size reduction is attained. This also leads to a reduction in production costs. Furthermore, variations between products due to errors in pasting can be reduced.

  Hereinafter, experimental examples performed according to the present embodiment will be described.

[Experimental Example 1]
As a result of monitoring the deterioration of the air compressor oil using the lubricating oil deterioration monitoring device 100 of the present invention equipped with a resin filter coated so as to obtain a transmitted light having a center wavelength of 550 nm and a half width of 80 nm. A certain degree of degradation index (cube root value calculated by MPU) is shown in FIG. Further, the degradation index and the remaining life data are plotted in FIG. In Fig. 2 (b), the remaining life indicated by the solid line is obtained separately in the laboratory for various properties of the deteriorated oil (viscosity, acid value, color, amount of impurities, residual amount of additive, etc.) The life is determined. Degradation index obtained from visible light transmittance is relatively consistent with the remaining life determined from a lot of data, and can be used as an index of degradation if the degradation behavior of each device is known. I understand.

[Experimental conditions in Experimental Example 1]
The experimental conditions in Experimental Example 1 are as follows.
LED used: Toyoda Gosei Cannonball type white LED lamp E1L53-AW0C30-01 type Applied voltage: 3.4V
-Distance through which light passes through the lubricating oil: 10 mm
-Light receiving element: S1336-44BK type, manufactured by Hamamatsu Photonics

[Experiment 2]
First transmitted light having a center wavelength of 450 nm and a half-value width of 80 nm, and second transmitted light having a center wavelength of 550 nm and a half-value width of 80 nm, the first transmitted light and the second transmitted light are provided. The industrial multipurpose oil was forcibly deteriorated in the laboratory using the lubricating oil deterioration monitoring device 100 of the present invention using a glass filter coated with a plurality of coatings so that the light transmission ratios were 40% and 60%, respectively. FIG. 3A shows a deterioration degree index (square root value calculated by MPU), which is a result of monitoring the deterioration degree. Further, the deterioration index and the remaining life data are plotted in FIG. It can be seen that the results agree well with the determination results taking into account all the data indicated by the solid line in FIG.

[Experiment 3]
A first transmitted light having a center wavelength of 450 nm and a half-value width of 80 nm, a second transmitted light having a center wavelength of 550 nm and a half-value width of 80 nm, and a center wavelength of 600 nm and a half-value width of 80 nm. Made of resin with a coating so that the transmission ratio of the first transmitted light, the second transmitted light, and the third transmitted light is 30%, 60%, and 10%, respectively. FIG. 4 shows a deterioration index (square root value calculated by MPU), which is the result of monitoring the degree of deterioration by forcibly degrading hydraulic fluid in a laboratory using the lubricating oil deterioration monitoring apparatus 100 of the present invention using a filter. Shown in (a). Further, the degradation index and the remaining life data are plotted in FIG. It can be seen that there is a good agreement with the determination result taking into account all the data indicated by the solid line in FIG.

DESCRIPTION OF SYMBOLS 1 ... Lubricating oil, 2 ... Measuring place, 3 ... Light source, 4 ... Filter, 5 ... Light receiving element, 6 ... ADC / MPU, 7 ... Display, 8 ... Personal computer, 10 ... Measuring unit, 100 ... Lubricating oil deterioration monitoring apparatus , GF1, GF2 ... glass fiber.

Claims (6)

  Visible light generated from a single light source is transmitted through the lubricating oil, received by a single light receiving element and converted into an electrical signal to detect deterioration of the lubricating oil, the light source and the light receiving element A lubricating oil deterioration monitoring device comprising a glass or resin filter with a single or a plurality of coatings for obtaining transmitted light having a predetermined center wavelength and a half-value width.   The filter obtains transmitted light having a center wavelength of 500 nm or more and less than 600 nm, a half width of 30 nm or more and less than 120 nm, and a total wavelength range to be measured of 350 nm or more and less than 750 nm. 1. Lubricating oil deterioration monitoring device according to 1. The filter is
A first transmitted light having a center wavelength of 400 nm or more and less than 500 nm and a half width of 30 nm or more and less than 100 nm; and a second transmitted light having a center wavelength of 500 nm or more and less than 575 nm and a half width of 30 nm or more and less than 100 nm. 2. The deterioration of lubricating oil according to claim 1, wherein the transmitted light is obtained such that transmission ratios of the first transmitted light and the second transmitted light are 0 to 80% and 20 to 100%, respectively. Monitor device. The filter is
A first transmitted light having a center wavelength of 400 nm or more and less than 500 nm and a half width of 30 nm or more and less than 100 nm; and a second transmitted light having a center wavelength of 500 nm or more and less than 575 nm and a half width of 30 nm or more and less than 100 nm; Further, the first transmitted light, the second transmitted light, and the third transmitted light are provided so as to have third transmitted light having a center wavelength in the visible range of 575 nm or more and less than 650 nm and a half width of 30 nm or more and less than 100 nm. 2. The lubricating oil deterioration monitoring device according to claim 1, wherein the transmitted light has a transmission ratio of 0 to 80%, 20 to 100%, and 0 to 60%.   The lubricating oil deterioration monitoring device according to any one of claims 1 to 4, wherein a condensing lens is used as the glass or resin to be coated in the filter.   The lubricating oil deterioration monitoring device according to claim 1, wherein the filter blocks ultraviolet rays and infrared rays.

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