JPH1019788A - Measurement system for soot in lubricating oil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately measure not only the concentration of soot (large carbon particle) in lubricating oil which causes the abrasion of a slide part, but also the grain size of soot and its distribution state. SOLUTION: A microcamera 1 captures light transmitted through a lubricating oil film to pick up an enlarged image of a soot group suspended in the lubricating oil, thereby obtaining a visible image through a development device 2 or generating an electric video signal immediately. The video signal is converted by an image processor 3 into a binary video signal having extremely high contrast. Consequently, a sharp image showing that only soot of large size floats like an island, so fine light and shade points arrayed on scanning lines forming the image are counted over more than one scanning lines to accurately calculate the area rate of the soot and then the concentration of the soot in the lubricating oil. Further, some successive light and shade points on one scanning line are counted to accurately calculate the particle size of the soot.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for controlling at least one of the concentration and the particle size distribution of a suit (relatively large carbon particles) contained when a lubricating oil such as an engine oil is deteriorated by long-term use. A system for measuring suits in lubricating oil for measuring.

[0002]

2. Description of the Related Art Since lubricating oils such as engine oils contain a dispersant as one of additives, the lubricating performance is improved even when foreign substances such as fine carbon particles are slightly mixed while the oil is fresh. There is no problem, but as the oil gets older, the dispersant gradually wears out and becomes ineffective,
Fine foreign matter agglomerates and grows into something like large carbon particles (suits), which becomes insoluble and lowers the lubrication performance of the oil. If a deteriorated oil containing a large amount of insoluble matter such as a suit is used, abrasion of the sliding portion inside the engine becomes severe and the life of the engine is shortened. Therefore, lubricating oil such as engine oil needs to monitor how much suit is contained in it, and the concentration of the suit indicates the degree of deterioration of the engine oil,
It is desirable to change the oil immediately when the concentration exceeds a predetermined value.

For this reason, Japanese Patent Application Laid-Open No. 7-20049 discloses a device for detecting the concentration of a suit in lubricating oil such as engine oil. In this detection device, a light-emitting portion and a light-receiving portion are attached to the left and right symmetric inclined surfaces at the top of a prism having a pentagonal cross section, and the bottom surface of the prism is brought into contact with engine oil which is a liquid to be inspected. When light is emitted from the light emitting unit toward the bottom of the prism at the incident angle where total reflection occurs, a part of the light enters the oil as evanescent waves from the bottom of the prism and is reflected by a relatively shallow layer. Returning to the prism again, it reaches the light receiving section together with the total reflected light, but at that time, a part of the evanescent wave hits the particles insoluble in the oil and is absorbed,
Since the amount of light reaching the light receiving unit is smaller than the amount of light emitted from the light emitting unit, the concentration of the insoluble component contained in the oil is calculated from the degree of the decrease. In addition to the above-mentioned conventional techniques, there is a technique for measuring a change in light transmittance in the lubricating oil in order to measure the concentration of the suit in the lubricating oil for the same purpose.

[0004]

All of these devices for measuring the concentration of insoluble components contained in engine oil are attached to automobile engines, and the concentration of insoluble components contained in engine oil is, for example, 3%. When the specified value is reached, the warning light is turned on to notify the driver that it is time to change the oil. And not. For this reason, it is possible to roughly grasp the timing of the target oil change, but the accuracy of the measurement result is not always high, and the concentration of insoluble matter such as suits in lubricating oil is accurately measured. Not suitable for use as a measuring instrument.

The amount of wear (wear ratio) generated in a lubricating portion such as a sliding portion of an internal combustion engine, which increases when the lubricating oil is deteriorated, depends on the valve cam of the internal combustion engine and the tappet on the valve side. As is clear from FIG. 3, which shows how the amount of wear generated on the top surface changes depending on the amount of the suit contained in the lubricating oil, the content (concentration) of the suit in the lubricating oil is increased. The higher, the higher, but not only the concentration of the suit, expressed as a percentage by weight, but also depending on the average particle size of the suit, as shown in FIG. come. That is,
Even if the concentration of the suit is the same, the wear amount is smaller when the average particle size of the suit is small, and the wear amount is larger when the average particle size is large.

[0006] As a conventional technique, as described in the above-mentioned example, the degree of reflection or absorption of light made incident on a lubricating oil from a prism as an evanescent wave is measured by an optical sensor that detects total reflected light, A device that measures light transmittance by using a light sensor provided on the opposite side by irradiating light into a thin film of oil has been developed. What can be known from the voltage value output by these light sensors, etc. Is only the concentration of the suit, it is not possible to measure up to the size of the particle size of the suit by the optical sensor, so the concentration of the suit, which can be measured by the prior art alone, how much it affects the wear It cannot be determined immediately.

[0007] The present invention addresses the aforementioned problems in the prior art and provides a lubricating oil in order to know in advance exactly how much wear the suit contained in the lubricating oil will actually cause. It is an object of the present invention to provide a system for measuring suits in lubricating oil that accurately measures the concentration of suits in oil. Another object of the present invention is to provide an improved system for measuring a suit in lubricating oil, which can measure both the concentration of the suit in lubricating oil and the particle size distribution of the suit.

[0008]

SUMMARY OF THE INVENTION The present invention provides a system for measuring a suit in lubricating oil according to the present invention as a means for solving the above-mentioned problems.

According to the first aspect of the present invention, the light incident on the lubricating oil in the oil observation unit is transmitted or reflected and then enlarged and imaged by the imaging means. The imaging means thereby forms an enlarged image of the suits floating in the lubricating oil. Based on this image, the image processing means scans the image vertically and horizontally on a plane and distinguishes the shading of a minute point on the scanning line with a predetermined threshold as a boundary, thereby providing an electrical and A binary video signal is generated. This binary video signal, if it is displayed as a visible image, results in an image with extremely high contrast. On the image, only the outline of a suit having a particle size equal to or larger than a predetermined value is displayed. Remains like an island, and other details have been erased.
Accordingly, the arithmetic means separately counts the number of binary video signals representing the shading of the image at a minute point on the scanning line for the video after the image processing, and performs necessary arithmetic operations, thereby achieving the target The concentration and particle size of the suit are accurately calculated.

According to the second aspect of the present invention, the imaging means is for temporarily reproducing the image of the lubricating oil including the suit as a visible image, and is provided with a developing means for that purpose. The image obtained by the development is not only storable as a record, but the image is read by another imaging means and converted into an electric video signal, and the video signal is converted by the image processing means in the same manner as described above. Is processed.

According to the third aspect of the present invention, since the imaging means is configured to magnify and image the suit group in the lubricating oil and simultaneously generate an electric video signal, the imaging means is visible. The video signal of the lubricating oil including the suit group is immediately output without passing through a typical image. Therefore, since the video signal is processed by the subsequent image processing means, the system configuration is simplified, and an electrical video signal can be obtained without passing through a visible image. And the measurement accuracy is improved.

Further, according to the fourth aspect of the present invention,
Since a means for generating an electrical and binary video signal is used as the imaging means, a final image can be obtained immediately without the need for an image processing means. Therefore, the system is immediately connected from the imaging unit to the calculation unit, and the system configuration is further simplified.

According to a fifth aspect of the present invention, the arithmetic means reads the final image or calculates the number of minute gray points arranged on a scanning line expressing the image. Separately, counting is performed over a plurality of scanning lines. Thus, the ratio of the area occupied by the suit to the target area is calculated, and the concentration of the suit in the lubricating oil can be accurately calculated from the area ratio. In addition, the particle size of the suit can be calculated by counting the continuous number of any one of light and shade points on one scanning line, so not only the density of the suit but also the particle size distribution of the suit, etc. Can be easily obtained, and the amount of wear of the sliding portion caused when the lubricating oil is used can be accurately predicted.

According to a sixth aspect of the present invention, the oil observation unit is composed of two glass plates that transmit light, and a slit for lubricating oil to be measured is formed between the two glass plates. At the same time, the width of the slit is variable with one movable relative to the other, so that the width of the slit can be expanded under normal conditions to allow lubricant to pass freely. In addition, when the measurement is performed, the width of the slit is sufficiently narrowed to realize an extremely thin lubricating oil film, and the measurement can be performed accurately and in real time.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described with reference to FIGS. 1 and 2, and FIGS. The system M for measuring a suit in the lubricating oil in this embodiment has a configuration as shown in the block diagram of FIG. 2 as a whole. First, the micro camera 1 generally has a function of combining a microscope and an image pickup device (camera) so that a microscopic object can be magnified (for example, 10000 times) and observed. In this embodiment, The lens system is similar to that of an optical microscope. The imaging device included in the micro camera 1 in this case uses a device that chemically records an image on a photosensitive film, similarly to a normal photographic camera.

However, as is well known,
There are various ways to record an enlarged image,
As another typical example, a video signal is generated by scanning and reading an image with a photoelectric tube, a semiconductor device, or the like, such as a television (video) camera.
In some cases, the video signal is electrically processed to reproduce an image on a display device such as a CRT, or the video signal is recorded by a magnetic or other recording device. Since the micro camera 1 does not have the same, an optical lens system of a microscope is attached to an image pickup device (camera) connected to various types of recording devices or display devices, or an optical lens system of relatively low magnification is used. After amplifying the electric video signal obtained by imaging by an electric circuit, display and record the image so as to increase the magnification, and view and enlarge the target image, including the one to be recorded. As long as recording is possible, commercially available ones can be used in appropriate combination.

In this embodiment, the developing device 2 chemically converts a latent image formed on a photosensitive film by the micro camera 1 into a visible image, and is a novel device itself. is not. If the image recording method is not a chemical method, for example, a method using static electricity, a latent image as an electrostatic image is formed on the surface of an electrical insulator through a lens system. Developing device 2
Corresponds to an electrophotographic developing device.

The image processing apparatus 3 according to this embodiment comprises:
In order to convert the visible image obtained by the developing process by the developing device 2 into an electric video signal (analog signal) and to enhance the contrast of the obtained video signal,
It is converted into a binary video signal (digital signal). Therefore, the image processing apparatus 3 of the illustrated embodiment includes a camera portion having a configuration similar to a television camera that generates an electric video signal by scanning an image appearing on a photosensitive film by scanning vertically and horizontally, and an output signal thereof. Is compared with a preset threshold value every predetermined short period, and comprises an A / D conversion circuit part which generates a digital signal of 1 when the value is larger than the threshold value and 0 when the value is smaller than the threshold value. .

However, if a micro-camera 1 that generates an analog video signal is used as in a normal television camera, the developing device 2 becomes unnecessary, and the image processing device 3 includes a photosensitive device. A portion corresponding to a television camera for reading an image on a film and converting the image into an electric signal becomes unnecessary. Furthermore, if a micro camera 1 that generates a video signal as a digital signal from the beginning in accordance with the brightness of a target scanning point is used, the image processing device 3 as well as the developing device 2 may not be necessary. . In the illustrated embodiment, the system having the developing device 2 as shown in FIG. 2 is used because an intermediate image can be stored as a photograph. At least the developing device 2 should be omitted by using a micro camera 1 that can obtain an electric video signal.

Next, the arithmetic unit 4 performs necessary calculations based on the video signal composed of the digital signals obtained by the image processing unit 3, calculates the density of the suit from the area ratio of the suit, and displays the image of the suit. Calculates the particle size distribution from the continuity of the data. The output signal is visually displayed on the display device 5, and may be configured to be supplied to some control device for controlling the operation of other devices, if necessary. Needless to say, the display device 5 may be a recording device such as a printer or a recorder.

In the illustrated embodiment, the micro-camera 1 can freely sample and observe the lubricating oil (engine oil) during operation of the internal combustion engine E as shown in FIG. is set up. That is, the micro camera 1 includes an inflow passage 7 for taking out a part of the lubricating oil as one branch of the oil line 6 of the internal combustion engine E, an oil observation unit 8 whose structure will be described later, and the oil observation unit 8
The lubricating oil is supplied to the oil pan 9 of the internal combustion engine E so as to face the oil observation unit 8 in the auxiliary system S including the outflow passage 10.

In the internal combustion engine E shown in FIG.
1 is a lubricating oil pump that sends pressurized lubricating oil to the oil line 6, 12 is a strainer, 13 is a branched lubricating oil passage that branches from the oil line 6 and supplies lubricating oil to each part of the internal combustion engine E, and 14 is a piston. , 15 indicate camshafts, respectively. Although not shown in FIG. 1 and FIG. 2, in order to operate the entire system including the micro camera 1 to the arithmetic unit 4 or the whole system including the display unit 5 in association with each other, for example, a microprocessor is included. An electronic control device or the like is provided as needed.

As shown in FIG. 5, the oil observation unit 8
The glass plates 16 and 17 are supported in parallel with a very small space (width) between them,
The inflow passage 7 and the outflow passage 1 are provided at both ends of the slit 18 so that the lubricating oil is supplied from the oil line 6 of the internal combustion engine E and flows through the narrow slit 18 formed between the slits 6 and 17.
0 (not shown). The width of the slit 18 is required to be about 10 μm or less, because the width of the slit 18 needs to be 10 times or less the particle diameter of the suit 20 contained in the lubricating oil 19 in the measurement state of the measurement system M. In the illustrated embodiment, the auxiliary system S including the inflow passage 7 and the outflow passage 10 is used in order to inspect the lubricating oil of the internal combustion engine E in real time. It is also possible to attach only the oil observation unit 8 to the micro camera 1 as a part of the measurement system M so that it can be used in a stationary state by injecting lubricating oil collected from an arbitrary object without using it. it can.

As described above, the slit 18 of the oil observation unit 8
It is necessary to make the width of the oil as small as possible. Therefore, in a system in which a part of the lubricating oil is sampled from the operating internal combustion engine E while being sampled as in the illustrated embodiment, such an oil observing unit 8 is initially provided with such an oil. Narrow slit 1
When the oil 8 is formed, the flow of the lubricating oil passing through the oil observation unit 8 is deteriorated, the flow velocity is reduced, and it takes a long time for the oil in the oil observation unit 8 to be replaced. Will be possible. Therefore, as shown in FIG. 6, a fixed glass plate 16 is formed in a U-shaped cross section, and a movable glass plate 17 is slidably engaged with the inside of the U-shaped glass plate 16. It may be formed as a shaped piston. In addition, as a seal between the respective ends of the glass plates 16 and 17, for example, the provision of a flexible sheet material (not shown) bonded to both ends should be considered. The movable glass plate 17 is fixed to the fixed glass plate 16 by means such as a hydraulic cylinder or a screw feeder (not shown).
, So that the width of the slit 18 can be freely enlarged and reduced.

During operation of the internal combustion engine E, the slit 1
By widening the distance between the slits 8 as shown in FIG.
The flow of the lubricating oil passing through the oil line 6 is improved so that the lubricating oil in the oil line 6 can freely pass through the slit 18 of the oil observation unit 8 from the inflow passage 7 and return to the oil pan 9 from the outflow passage 10. . When the measurement of the measurement system M is performed, the movable glass plate 17 is brought close to the fixed glass plate 16 so that the distance between them is about 10 μm. Thereby, the micro camera 1 can observe light transmitted through a thin oil film having a thickness of about 10 μm or less,
High measurement accuracy can be obtained. In the illustrated embodiment, the transmitted light of the oil film is observed by the micro camera 1, but in some cases, the reflected light may be observed.

Since the system M for measuring a suit in lubricating oil according to the embodiment is configured as described above, the oil of the internal combustion engine E is operated during the operation of the internal combustion engine E using the lubricating oil to be measured. A part of the lubricating oil is diverted from the line 6 and flows into the slit 18 of the oil observation unit 8 from the inflow passage 7. Since the lubricating oil further returns to the oil line 6 of the internal combustion engine E again through the outflow passage 10, the lubricating oil of the internal combustion engine E is constantly flowing through the slit 18 of the oil observation unit 8, and the measuring system M thus operates as described above. The lubricating oil circulating in the internal combustion engine E can be inspected uniformly and in real time.

When the measurement is performed, the slit 1 is moved by moving the movable glass plate 17 of the oil observation unit 8.
8 is reduced to about 10 μm. Fixed glass plate 1
Since a light source or a reflecting mirror (not shown) is provided behind 6, light rays emitted from the light source pass through the oil film of the slit 18 and enter the micro camera 1. The image formed on the photosensitive film of the micro camera 1 is developed by the developing device 2 as described above to generate a visible image as shown in FIG. This image shows that a relatively large suit 20 is floating like an island in the lubricating oil 19, but between the suit 20 extremely fine carbon particles are shown like a cloud. The image of the suit 20 has shading, and the outline of the suit 20 is unclear.

Therefore, the image shown in FIG. 8 is read by an image pickup device (not shown) such as a television camera that scans and picks up an image in the image processing device 3 and converts it into an electric video signal. Since the video signal is an analog signal, it is converted into a digital signal by an A / D conversion circuit. Specifically, the analog signal is cut at a minute unit time, and the signal intensity at each unit time, that is, the signal intensity shown in FIG.
A signal of 1 is generated when the degree of shading (darkness or brightness) of a minute point on the scanning line in the image of FIG. 1 exceeds a predetermined threshold, and a signal of 0 is generated when the degree does not exceed the same threshold. , And eliminates intermediate ambiguous gradations. Depending on how the threshold is selected, a point belonging to the area of the suit 20 is set to signal 1 and a point in an area other than the suit 20 is set to signal 0. When the video signal as a digital signal obtained in this way is displayed on a display device 5 composed of, for example, a CRT, FIG.
Is obtained. In the image of FIG. 9, the boundary between the suit 20 and the lubricating oil 19 is sharp, and clouds due to intermediate fine carbon particles and shading of the suit 20 are removed, so that the contour of the island-shaped suit 20 is clear. It has become something.

Next, a necessary operation is performed in the arithmetic unit 4 based on a video signal representing an image as shown in FIG. First, the mixed amount (density) of the suit is calculated by calculating the ratio of the area of the suit 20 group to the unit area of the image as shown in FIG. 9, that is, the area ratio. Specifically, by counting the number of signals 1 per unit area of the image, the total area of the 20 groups of suits therein can be determined, and the number is determined by the size of the unit area, that is, the signal 1 and the signal 0 Is divided by the sum of the numbers of the signals, and the amount of the mixed suit = (the number of the signals 1 / the number of the signals 1 + the number of the signals 0) × 100%. This is a value corresponding to the concentration of the suit that can be measured in the prior art, but can be measured with higher accuracy.

As described above, by performing a simple calculation in the arithmetic unit 4, not only the density of the suit can be measured with higher accuracy than the conventional technique, but in the illustrated embodiment, the suit is characterized as a feature of the present invention. The average particle size of the suit 20 can be measured, and the particle size distribution of the suit 20 can be calculated based on the average particle size. That is, for example, when the scanning line is horizontally moved from the upper left to the right of the image as shown in FIG. 9 and is sequentially moved to the lower stage, the number of successive appearances of the signal 1 is counted. , That is, the particle size is calculated.

The maximum value or the average value of the calculated particle diameters is obtained, or the suit 20 having a particle size larger than a predetermined size is determined.
Counting the number can be easily performed by the arithmetic unit 4. Further, when several steps are determined for the particle size and the frequency of appearance is counted for each particle size, an accurate particle size distribution table can be obtained. FIG. 10 shows an example of measurement results obtained by the measuring system for suits in lubricating oil according to the present invention.

In addition, it is possible to easily calculate how much fine particles having a relatively small particle size are included in the suit 20 contained in the lubricating oil. For example, when a target in which the number of continuations of signal 1 is 1 or more and 5 or less is regarded as fine particles, the ratio of fine particles = the number of continuations of signal 1 is 1 to 5 / the number of continuations of signal 1 is 1 to n The content of the fine particles is found as a number × 100%.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a connection relationship between an internal combustion engine operated by a lubricating oil to be measured by the system of the present invention and the system of the present invention.

FIG. 2 is a block diagram illustrating a configuration of a measurement system according to an embodiment of the present invention.

FIG. 3 is a graph showing the effect of the content of a suit in lubricating oil on the amount of wear.

FIG. 4 is a graph showing the influence of the particle size distribution of a suit in lubricating oil on the amount of wear.

FIG. 5 is a sectional view conceptually showing a configuration of an oil observation unit.

FIG. 6 is a perspective view showing an expanded state of an oil observation unit.

FIG. 7 is a perspective view showing a measurement state of an oil observation unit.

FIG. 8 is a view showing an image of lubricating oil captured by a micro camera.

FIG. 9 is a diagram illustrating a binary image obtained by performing image processing on the image of FIG. 8;

FIG. 10 is a diagram illustrating a measurement result by the measurement system of the present invention.

[Explanation of symbols]

 E: Internal combustion engine M: Measurement system of the embodiment S: Auxiliary system 1: Micro camera 3: Image processing device 4: Computing device 6: Oil line 8: Oil observation unit 16: Fixed glass plate 17: Movable glass plate 18 ... Slit 19 ... Lubricant 20 ... Suit

Claims (6)

[Claims] 1. An imaging unit for enlarging and imaging a group of suits in the lubricating oil by observing light incident on the lubricating oil in an oil observation unit, and a lubrication device including the group of suits captured by the imaging unit. Image processing means for scanning the image of oil to generate electrical and binary video signals corresponding to the density by distinguishing the density of minute points on the scanning line at a predetermined threshold, Calculating means for counting the number of the minute shades arranged on the scanning line based on the binary video signal and performing necessary calculations. Suit measuring system. 2. The image processing apparatus according to claim 1, further comprising: a developing unit for developing the image captured by the imaging unit as a visible image, and another imaging unit for converting the developed image into an electric video signal. The system for measuring suits in lubricating oil according to claim 1. 3. The lubricating oil according to claim 1, wherein said imaging means is configured to magnify and image the suit group in said lubricating oil and generate an electric video signal. Suit measuring system. 4. The lubricating oil according to claim 1, wherein said image pickup means also serves as said image processing means by generating an electric and binary video signal. Suit measurement system. 5. The calculating means calculates the area ratio occupied by the suit by counting the number of minute shading points arranged on the scanning line over a plurality of the scanning lines, and calculates the area ratio occupied by the suit. The method according to claim 1, further comprising calculating a concentration of the suit contained in the lubricating oil, and calculating a particle size of the suit from a continuous number of the light and shade points on one scanning line. Item 5. A system for measuring a suit in lubricating oil according to any one of Items 1 to 4. 6. The oil observation section is composed of two glass plates that transmit light, a slit for lubricating oil is formed between the two glass plates, and the width of the slit is The system for measuring suits in lubricating oil according to any one of claims 1 to 5, wherein the system is variable.