JP2000171396A - Concentration detecting device for oil deteriorating matter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a concentration detecting device for oil deteriorating matter, which is capable of detecting both the concentration of carbon particles and the concentration of oxidation deterioration product. SOLUTION: This concentration detecting device includes a carbon particle concentration detecting part 10 having a first light emitting element 11 for radiating first test light, a first light guide element 4 for guiding the first test light to a contact liquid surface, a first photo sensor 12 for detecting the first test light total-reflected on the contact liquid surface of the first light guide element 4 and a first detection circuit connected to the first photo sensor 2 for determining the carbon particle concentration and an oxidation deterioration product concentration detecting part 2 having a second light emitting element 21 for emittng a second test light different from the first test light, a second light guide element 4 for guiding a second test light to the contact liquid surface, a second photo sensor 22 for detecting the second test light total-reflected on the contact liquid surface of the second light guide element 4, and a second detection circuit connected to the second photo sensor 22 for determining the concentration of oxidation deterioration product.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for detecting the concentration of a deteriorated oil which is a cause of oil deterioration in oil having a low light transmittance.

[0002]

2. Description of the Related Art For example, lubricating performance of an engine oil such as a diesel engine changes depending on the degree of deterioration, and it is important to grasp the degree of deterioration. The deterioration of oil progresses due to the inclusion of carbon particles generated by combustion in the engine and the like, oxidation of components of the oil, or deterioration products (hereinafter referred to as oxidation deterioration products) generated in the oxidation process. Examples include carboxylic acids and esters.

Conventionally, a method has been used in which the content of carbon particles generated in oil is detected, and this is used as an index for determining oil deterioration. For example, as shown in FIG. 10, the conventional concentration detecting device 90 has the inspection light 31 on the first liquid contact surface 911 of the light guide 91 whose tip is immersed in the oil 8.
And the optical sensor 93 detects the inspection light 31 totally reflected by the second and third liquid contact surfaces 912 and 913. . In the figure, reference numeral 92 denotes a light emitting element that emits the inspection light 31.

The inspection light 31 detected by the optical sensor 93 is
Inspection light 3 totally reflected by second and third liquid contact surfaces 912 and 913
1 and its strength varies depending on the particle concentration in the oil 8. That is, the light totally reflected by the liquid contact surface 911 is absorbed and scattered by the carbon particles in the oil 8 as a so-called evanescent wave, and the intensity thereof is changed (Japanese Unexamined Patent Application Publication No.
No. 11174).

The above-mentioned concentration detecting device 90 utilizes total reflection on the liquid contact surfaces 911 to 913 with the oil 8 and detects light transmitted through the liquid to be inspected (Japanese Patent Laid-Open No. 61-1986). 164144), there is an advantage that it is not affected by the light transmittance of the liquid to be tested. Therefore, the present invention can be used for oil which is a liquid having a very low light transmittance.

Japanese Patent Application Laid-Open No. 9-33426 discloses that
A density detecting device in which the above-described density detecting device 90 is further improved is shown. That is, particles and contaminants in oil adhere to the liquid contact surface, which is a problem of the concentration detection device 90, and the detection accuracy is reduced. An apparatus has been disclosed which improves fluid flow resistance when a (light guide) is protruded to obstruct the flow of a liquid to be inspected. The use of this improved concentration detector makes it possible to stably and accurately obtain the concentration of carbon particles in oil.

[0007]

However, the above-mentioned conventional concentration detecting device has the following problems. That is, the deterioration of the oil proceeds not only due to an increase in the content of carbon particles, but also due to an increase in the above-mentioned oxidatively degraded products generated by the modification of the oil. Therefore, depending on the type of oil, an increase in oxidative degradation products may have a greater effect on the progress of oil degradation than an increase in carbon particles. In this case,
Simply measuring the concentration of carbon particles does not provide a precise grasp of the degree of oil degradation. Therefore, development of a concentration detection device capable of detecting both the concentration of carbon particles and the concentration of oxidation degradation products has been desired.

The present invention has been made in view of such a conventional problem, and provides an oil-deteriorated substance concentration detecting apparatus capable of detecting both the concentration of carbon particles and the concentration of oxidatively degraded products. What you want to do.

[0009]

According to a first aspect of the present invention, there is provided a first light emitting body which emits a first inspection light for detecting carbon particles in oil, and a liquid contact surface between the first light emitting body and the oil immersed in the oil. A first light guide for guiding the first inspection light to the first light sensor, a first optical sensor for detecting the first inspection light totally reflected on the liquid contact surface of the first light guide, and a connection to the first optical sensor. A first detection circuit having a first detection circuit for determining the concentration of carbon particles, and a second inspection light having a wavelength different from the first inspection light for detecting oxidation degradation products in the oil. Second
A luminous body, a second light guide that is immersed in oil and guides the second inspection light to a liquid contact surface with the oil, and a second inspection light that is totally reflected by the liquid contact surface of the second light guide. Oil degradation, comprising: a second optical sensor for detecting the concentration of oxidative degradation products; and a second detection circuit connected to the second optical sensor for determining the concentration of oxidative degradation products. In the object concentration detector.

What is most notable in the present invention is that it has both the above-mentioned carbon particle concentration detecting section and the above-mentioned oxidation degradation product concentration detecting section. Here, the above-mentioned oxidative deterioration product is a product generated by oxidation of oil components or its oxidation process. Specifically, there are, for example, carboxylic acids and esters.

As the first inspection light, light having a wavelength capable of absorbing or scattering an evanescent wave by the carbon particles is used. On the other hand, as the second inspection light, light having a wavelength different from that of the first inspection light and capable of absorbing or scattering an evanescent wave by the oxidation degradation product is used. As a specific wavelength,
For example, an infrared ray having a wavelength in a region described later can be used.

The first light guide is configured to transmit the first inspection light, and the second light guide is configured to transmit the second inspection light. Further, the first light guide and the second light guide may be separately provided, or one light guide may be shared. In the case of common use, it is necessary that the light guide has a characteristic of transmitting both the first inspection light and the second inspection light.

[0013] The first optical sensor is configured to detect the intensity of the first inspection light totally reflected from the liquid contact surface.
The second optical sensor is configured to detect the intensity of the second inspection light totally reflected from the liquid contact surface. The first detection circuit connected to the first optical sensor and the second detection circuit connected to the second optical sensor may be provided separately, or may be provided so as to share some circuits and the like. Is also good.

Next, the operation and effect of the present invention will be described.
The oil degradation product concentration detection device of the present invention has the oxidation degradation product concentration detection unit as well as the carbon particle concentration detection unit. These can detect the concentrations of carbon particles and oxidative degradation products contained in the oil, respectively.

That is, in the carbon particle concentration detecting section, the first inspection light radiated from the first light emitter is totally reflected by the liquid contact surface of the first light guide, and is received by the first optical sensor. . Then, the first detection circuit detects the carbon particle concentration from the intensity of the first inspection light received by the first optical sensor.

On the other hand, the oxidation degradation product concentration detecting section
The second inspection light emitted from the second light emitter is totally reflected on the liquid contact surface of the second light guide, and is received by the second optical sensor. Then, the second detection circuit detects the concentration of the oxidation degradation product from the intensity of the second inspection light received by the second optical sensor.

As described above, the concentration detecting device of the present invention has
The stage can detect both the carbon particle concentration and the oxidation degradation product concentration. Therefore, by using this concentration detection device, it is possible to determine not only oil deterioration due to an increase in the concentration of carbon particles, but also an oil deterioration state due to an increase in the concentration of oxidation degradation products. Therefore,
The criterion for determining oil deterioration can be set arbitrarily in accordance with the type of oil that is the object to be measured, and fine deterioration determination can be performed according to the characteristics of the oil.

As described above, according to the present invention, it is possible to provide a concentration detector for oil-deteriorated substances capable of detecting both the concentration of carbon particles and the concentration of oxidatively degraded products.

Next, the first inspection light is an infrared ray having a wavelength of 0.7 to 1.1 μm, and the second inspection light is a wavelength of 0.95 to 7 μm. And the wavelength of the second inspection light is preferably larger than the wavelength of the first inspection light. Thus, the concentration of carbon particles can be detected with high accuracy using the first inspection light, and the concentration of oxidative degradation products can be detected with high accuracy using the second inspection light. On the other hand, when the wavelengths of the first inspection light and the second inspection light are out of the above specific ranges, absorption and scattering of the evanescent wave by the carbon particles or the oxidative degradation products are reduced, and the detection of these concentrations is not performed. It will be difficult.

Further, as in the third aspect of the present invention, the first light guide and the second light guide are integrally formed, and both the first inspection light and the second inspection light are used. It is preferable that the prism is made of a transparent material. In this case, the number of parts can be reduced, the device can be made more compact, and the like. Further, as the prism, for example, CaF, Ba
F or the like can be used as the material.

According to a fourth aspect of the present invention, the prism has the liquid contact surface at the tip of a cylindrical or prismatic shape. A bottom portion comprising a plane substantially perpendicular to the incident direction of the second inspection light;
The first inspection light includes a first inclined surface, a bottom surface portion, and a third inclined surface which sequentially surround the periphery of the bottom surface portion.
Preferably, the second inspection light travels by totally reflecting off the second inclined surface, the bottom surface portion, and the fourth inclined surface. With this configuration,
Although they are integrated, the paths of the first inspection light and the second inspection light can be separately secured.

Further, as in the invention according to claim 5, the first detection circuit and the second detection circuit are configured to share one detection circuit, and the detection circuit includes the first optical circuit. Preferably, it is electrically connected to both the sensor and the second optical sensor. In this case, by sharing the first detection circuit and the second detection circuit, it is possible to reduce the size and cost of the device. Further, the control of the detection circuit in this case can be performed by switching the function as the carbon particle concentration detection unit and the function as the oxidation degradation product concentration detection unit at predetermined intervals using a timer, for example.

According to a sixth aspect of the present invention, the carbon particle concentration detector detects a first monitor light emitted together with the first inspection light from the first light emitter. A sensor, wherein the first monitor sensor is electrically connected to the first detection circuit;
The oxidation degradation product concentration detection section has a second monitor sensor for detecting a second monitor light emitted together with the second inspection light from the second luminous body, and the second monitor sensor is The first detection circuit is electrically connected to the second detection circuit, and the first detection circuit determines the carbon particle concentration using an output value from the first optical sensor and an output value from the first monitor sensor. In the second detection circuit,
It is preferable that the configuration is such that the concentration of the oxidation degradation product is determined using the output value from the second optical sensor and the output value from the second monitor sensor.

In this case, the first and second monitor sensors detect the intensities of the first and second monitor lights radiated from the first and second light emitters. The radiation state of the first and second inspection lights can be grasped at any time. Therefore, in detecting the carbon particle concentration, in the first detection circuit, the intensity of the first inspection light output from the first optical sensor is determined by the intensity of the first monitor light output from the first monitoring sensor. By performing correction or the like, the detection accuracy of the carbon particle concentration can be improved.

Similarly, in detecting the oxidation degradation products, the second detection circuit uses the second detection circuit to determine the intensity of the second inspection light output from the second optical sensor and the second inspection light output from the second monitoring sensor. By performing correction or the like based on the intensity of the monitor light, the detection accuracy of the concentration of the oxidation degradation product can be improved.

Further, as in the invention according to claim 7, the liquid contact surfaces of the first light guide and the second light guide are covered with a cover member and are provided inside the cover member. A cleaning member floating in the oil is enclosed, and the cover member has an oil inlet provided on the upstream side to oppose the flow of the oil, and an oil outlet provided on the downstream side of the oil. It is preferable to adopt a structure in which the opening area of the oil outlet is larger than the opening area of the oil inlet.

In this case, the first light guide and the first light guide are formed by the presence of the cleaning member and the formation of a jet of oil in the cover member by regulating the opening area of the oil outlet and the oil inlet. The contamination of the liquid contact surface of the second light guide can be prevented. As a result, it is possible to maintain the detection accuracy of the concentrations of the carbon particles and the oxidation degradation products.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment An apparatus for detecting the concentration of degraded oil according to an embodiment of the present invention will be described with reference to FIGS. The concentration detection device 1 of the present embodiment is a device for determining the deterioration of engine oil of a diesel engine, and detects the concentrations of carbon particles and oxidative degradation products generated in the oil, respectively.

FIG. 1, FIG. 2, and FIG.
As shown in FIG. 5, a first luminous body 11 that emits a first inspection light 31 for detecting carbon particles in the oil 8,
A first light guide 4 that is immersed in the oil 8 and guides the first inspection light 31 to a liquid contact surface 40 with the oil 8;
A first optical sensor 12 for detecting the first inspection light 31 totally reflected by the liquid contact surface 40, and a first detection circuit 5 connected to the first optical sensor 12 for determining the carbon particle concentration. It has a density detector 10.

As shown in FIGS. 3 to 5, the concentration detecting device 1 includes a second inspection light 32 having a wavelength different from that of the first inspection light 31 for detecting oxidation degradation products in oil.
A second luminous body 21 that emits light, a second light guide 4 that is immersed in the oil 8 and guides the second inspection light 32 to a liquid contact surface 40 with the oil 8, A second optical sensor 22 for detecting a second inspection light 32 totally reflected on the liquid contact surface 40,
An oxidation degradation product concentration detector 2 having a second detection circuit 5 connected to the second optical sensor 22 for determining the concentration of the oxidation degradation product.

Hereinafter, this will be described in detail. As shown in FIGS. 1 to 5, the concentration detection device 1 of this embodiment
1, the first light guide for transmitting the second inspection light 32 and the second
The first light 31 and the second light 31 are integrated with the light guide.
The prism 4 made of a material that transmits both the inspection light 32 was used. The prism 4 is held by a synthetic resin holder 6 and housed in a housing 69. Above the holder 6, the first luminous body 11 and the like are disposed, and further above the printed wiring board 50 on which a detection circuit 5 described later is mounted is disposed. The printed wiring board 50 is electrically connected to the outside via a connector 59 (FIG. 1).

Next, the first inspection light 31 in the carbon particle concentration detecting section 10 was an infrared ray having a wavelength of about 0.94 μm. The infrared light of this wavelength can absorb and scatter the evanescent wave by carbon particles in the oil, and the intensity changes depending on the carbon particle concentration.

On the other hand, the second inspection light in the oxidation degradation product concentration detector 2 was an infrared ray having a wavelength of about 6 μm. The infrared ray of this wavelength can absorb and scatter the evanescent wave by the oxidation degradation product concentration detection unit in the oil, and the intensity changes depending on the oxidation degradation product concentration detection concentration. Here, in the oil 8, carboxylic acids, esters and the like are generated as the above-mentioned oxidative deterioration products. In this example, the wavelength at which the evanescent wave is absorbed and scattered by the nitric acid ester is particularly selected.

Next, as shown in FIG. 6, the prism 4 has an octagonal prism shape made of a material capable of transmitting infrared rays having both wavelengths of around 0.94 μm and around 6 μm. The prism 4 has a liquid contact surface 4 at the tip of the octagonal prism.
It has 0. As shown in FIGS. 6A and 6B, the liquid contact surface 40 has a bottom surface portion 400 formed of a plane substantially perpendicular to the incident direction of the first inspection light 31 and the second inspection light 32, and a bottom surface portion 4.
First to fourth inclined surfaces 401 to 40 that sequentially surround the periphery of 00
4

The inclined surfaces 401 to 404 are formed by cutting out the four corners at the tip of the octagonal prism at an angle of 45 degrees. Then, as described later, the first inspection light 31 is transmitted to the first inclined surface 401 and the bottom surface 40.
The second inspection light 32 travels through total reflection on the second and third inclined surfaces 403, 404, and 404. is there.

As shown in FIG. 6C, a reflecting surface 42 having apertures 421 to 424 for transmitting only the first and second inspection light beams 31 and 32 is provided on the upper end surface of the prism 4.
0 was provided. The aperture 42 on the reflection surface 420
Portions other than 1 to 424 are provided so as to totally reflect light.

As described above, the holder 61 made of synthetic resin is disposed above the prism 4. As shown in FIG.
As shown in the figure, at the positions corresponding to the apertures 421 to 424, circular translucent holes 611 to 614 having a circular cross section are provided, and first and second monitor lights 33,
34, a rectangular light-transmitting hole 615 having a rectangular section
616 are provided.

Above the holder 61, as shown in FIG. 5, the first light-emitting body 11, the second light-emitting body 21, and the first optical sensor 1
2, the second optical sensor 22, the first monitoring sensor 13, the second
A monitoring sensor 23 is provided. The first monitor sensor 13 and the second monitor sensor 23 are for correcting output values of the first optical sensor 12 and the second optical sensor 22, respectively, as described later.

As shown in the figure, the first illuminant 11 is provided at a position where radiated light can enter both the round light transmitting hole 611 and the rectangular light transmitting hole 615. And the first illuminant 11
Out of the emitted light, the light incident on the round light transmitting hole 611 becomes the first inspection light 31, and the light incident on the rectangular light transmitting hole 615 becomes the first monitor light 33. Also, the first optical sensor 12
Are provided to face the round light transmitting hole 613 as shown in FIG. Further, the first monitor sensor 13 is provided so as to face one end of the rectangular light transmitting hole 615. The first illuminant 11, the first optical sensor 12, and the first monitoring sensor 13 are the main components of the carbon particle concentration detector 10.

Further, as shown in FIG.
Are provided at positions where radiated light can enter both the round light transmitting hole 612 and the rectangular light transmitting hole 616. Then, of the radiated light from the second light emitting body 21, the light incident on the round light transmitting hole 612 becomes the second inspection light 32, and the light incident on the rectangular light transmitting hole 616 becomes the second monitor light 34. Further, as shown in the figure, the second optical sensor 22 is provided to face the round light transmitting hole 614. Further, the second monitor sensor 23 is provided so as to face one end of the rectangular light transmitting hole 616. The second light-emitting body 21, the second optical sensor 22, and the second monitoring sensor 23 are main components of the oxidation degradation product concentration detector 2.

Next, as shown in FIG. 8, in the present embodiment, the first detection circuit and the second detection circuit share one detection circuit 5. That is, the detection circuit 5
As shown in the figure, conversion amplifier (AMP) 53, division circuit 54, determination circuit (CP) 55, alarm circuit (ALM) 5
6, which are electrically connected to the driver circuit 51 and the sensors 12, 13, 22, and 23.

The driver circuit 51 drives the first luminous body 11, the second luminous body 21, and the detection circuit 5, and manages the driving timing of these to control the carbon particle concentration detection section 10 and the oxidation. The operation of the deterioration product concentration detection unit 2 is switched alternately. Further, a temperature sensor 515 is connected to the driver circuit 51. The driver circuit 51 is configured to drive the first luminous body 11 or the second luminous body 21 only when the temperature of the oil 8 becomes equal to or higher than a predetermined temperature.

Further, in the density detecting device 1 of this embodiment,
As shown in FIGS. 1 to 4, the liquid contact surface 40 of the prism 4 is
A cleaning member 75 that is covered with the cover member 7 and floats in the oil 8 is sealed inside the cover member 7. The cover member 7 has an oil inlet 71 provided on the upstream side to face the flow of the oil 8 and an oil outlet 72 provided on the downstream side of the oil.
The opening area of the oil outlet 72 was larger than the opening area of the oil inlet 71.

Next, the operation and effect of this embodiment will be described. In the case of detecting the concentration of carbon particles in the concentration detection device 1 of the present embodiment, as shown in FIG.
1 drives the first light emitting body 11. As a result, the first
Infrared light having a wavelength of 94 μm emitted from the light emitter 11 is incident on the round light transmitting hole 611 and the rectangular light transmitting hole 615 of the holder 6, respectively, and the first inspection light 31 (FIG. 1).
And the first monitor light 33 (FIG. 2).

As shown in FIG. 1, the first inspection light 31 enters the prism 4 through the circular light transmitting hole 611 and the aperture 421. Next, the first inspection light 31 is applied to the liquid contact surface 4.
0, the first inclined surface 401, the bottom portion 400, the third
Are sequentially reflected by the inclined surface 403, and are received by the first optical sensor 12 through the aperture 423 and the round light transmitting hole 613. The first inspection light 31 is received by the first optical sensor 12 in a state where the so-called evanescent wave is absorbed and diffused by the carbon particles at the time of total reflection at the liquid contact surface 40, and the intensity is reduced accordingly.

On the other hand, as shown in FIG. 2, the first monitor light 33 reaches the reflection surface 420 at the upper end of the prism 4 through the rectangular light transmitting hole 615, is totally reflected there, and is again rectangular light transmitting. The light is received by the first monitor sensor 13 through the hole 615. The first monitor light 33 is reflected by the reflection surface 420.
, The light is received while maintaining the intensity at the time of radiation.

Next, as shown in FIG.
(PHD) 12 and first monitor sensor (PHD) 13
Are connected to the conversion amplifier 53 of the detection circuit 5
Output value I₁0, I₁Send 1 Conversion amplification
In the unit 53, the output value I ₁0, I₁1 is the voltage signal V
₁, V₂And sends it to the division circuit 54. Division times
In the road 43, the reflectance σ (σ∝V₁/ V₂) Is calculated.
This reflectance σ is used as a reference value σ in the next judgment circuit 55._S1
, And the carbon particle concentration α is calculated. Next
In the alarm circuit 56, the above carbon particle concentration α is used as a reference.
Concentration α_SIf this exceeds the standard value,
Alarms outside.

Similarly, when detecting the concentration of the oxidation degradation product, the second light emitting body 21 is driven by the driver circuit 51 as shown in FIGS. As a result, the infrared light having a wavelength of about 6 μm emitted from the second light emitting body 21 is incident on the round light transmitting hole 612 and the rectangular light transmitting hole 616 of the holder 6, respectively, and the second inspection light 32 and the second light are respectively transmitted. It is divided into two monitor lights 34.

As shown in FIG. 3, the second inspection light 32 passes through the circular light-transmitting hole 612, the aperture 422 and the prism 4
Invade. Next, the second inspection light 32 is totally reflected by the second inclined surface 402, the bottom surface 400, and the fourth inclined surface 404 on the liquid contact surface 40 in order, passes through the aperture 424, and the round light transmitting hole 614. The light is received by the second optical sensor 22. When the second inspection light 32 is totally reflected by the liquid contact surface 40, the so-called evanescent wave is absorbed and diffused by the oxidation degradation product, and the second inspection light 32 is reduced in intensity by the second inspection light 32.
The light is received by the optical sensor 22.

On the other hand, as shown in FIG. 4, the second monitor light 34 reaches the reflecting surface 420 at the upper end of the prism 4 through the rectangular light transmitting hole 616, is totally reflected there, and is again rectangular light transmitting. The light is received by the second monitor sensor 23 through the hole 616. The second monitor light 34 is reflected by the reflection surface 420
, The light is received while maintaining the intensity at the time of radiation.

Next, as shown in FIG.
(PHD) 22 and second monitor sensor (PHD) 23
Are connected to the conversion amplifier 53 of the detection circuit 5
Output value I₂0, I₂Send 1 Conversion amplification
In the unit 53, the output value I ₂0, I₂1 is the voltage signal V
₁, V₂And sends it to the division circuit 54. Division times
In the road 43, the reflectance σ (σ∝V₁/ V₂) Is calculated.
This reflectance σ is used as a reference value σ in the next judgment circuit 55._S2
, And the oxidation degradation product concentration β is calculated. Next
In the alarm circuit 56, based on the above-mentioned oxidation degradation product concentration β,
Subconcentration β_SIf this exceeds the reference value compared to
Will issue an external alarm.

The operation of the carbon particle concentration detecting section 10 and the operation of the oxidation degradation product concentration detecting section 2 are periodically switched in accordance with an instruction from the driver circuit 51. Specifically, when the carbon particle concentration detector 10 operates, the driver circuit 5
The first light emitter 11 is driven by the instruction of 1, and the amplification factor of the conversion amplifier 53, the reference value σ _S1 in the determination circuit 55, and the reference concentration α _S in the alarm circuit 56 are switched to those for carbon particles.

On the other hand, when the oxidation degradation product concentration detecting section 2 is operated, the second light emitting body 21 is driven by the instruction of the driver circuit 51, and the amplification factor of the conversion amplifier 53,
The reference value σ _S2 in the judgment circuit 55 and the reference concentration β _S in the alarm circuit 56 are switched to those for oxidation degradation products.

As described above, the density detecting device 1 of the present embodiment
One unit can detect both the carbon particle concentration and the oxidation degradation product concentration. Therefore, by using the concentration detection device 1, it is possible to determine not only oil deterioration due to an increase in the concentration of carbon particles but also an oil deterioration state due to an increase in the concentration of oxidative degradation products. Therefore, it is possible to arbitrarily set the criteria for determining oil deterioration according to the type of the oil 8 that is the object to be measured, and it is possible to perform a detailed deterioration determination according to the characteristics of the oil.

Further, in this embodiment, one prism 4 is shared as the first light guide and the second light guide, and one detection circuit 5 is used as the first detection circuit and the second detection circuit. Is shared. As a result, the number of parts in the entire system is reduced,
The apparatus can be made compact and the like.

The carbon particle concentration detector 10 and the oxidation degradation product concentration detector 2 are configured to measure the intensities of the first monitor light 33 and the second monitor light 34, respectively. Therefore, these monitor lights 3
3, 34, the first and second luminous bodies 11, 21 are measured.
This makes it possible to correct the variation in the radiation performance and to more accurately detect the concentration of carbon particles and the concentration of oxidation degradation products.

In this embodiment, the liquid contact surface 40 of the prism 4 is covered with a cover member 7 and a cleaning member 75 floating in the oil 8 is sealed inside the cover member 7. Further, the opening area of the oil outlet 72 is larger than that of the oil inlet 71. Thereby, contamination of the liquid contact surface 40 of the prism 4 can be prevented, whereby the detection accuracy of the concentrations of carbon particles and oxidation degradation products can be maintained.

Embodiment 2 As shown in FIG. 9, this embodiment is an example in which the shape of the prism 4 in Embodiment 1 is changed from an octagonal column to a column. That is, as the prism 4 of the present example, a prism-shaped prism was used. The prism 4 has a liquid contact surface 40 at the end of the columnar shape.

As shown in the drawing, the liquid contact surface 40 has a bottom surface 400 formed of a plane substantially perpendicular to the incident direction of the first inspection light 31 and the second inspection light 32, and a second surface surrounding the bottom surface 400 in order. It comprises first to fourth inclined surfaces 401 to 404. These inclined surfaces 401 to 404 are formed by cutting out the four corners of the columnar tip at an oblique angle of 45 degrees. Others are the same as the first embodiment. In this embodiment, the same operation and effect as those of the first embodiment can be obtained.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing an optical path (a cross section taken along line AA in FIG. 5) of first detection light of a concentration detection device in a first embodiment.

FIG. 2 is an explanatory diagram showing an optical path (a cross section taken along line BB of FIG. 5) of a first monitor light of the density detection device in the first embodiment.

FIG. 3 is an explanatory diagram showing an optical path (a cross section taken along line CC in FIG. 5) of second detection light of the concentration detection device in the first embodiment.

FIG. 4 is an explanatory view showing an optical path (a cross section taken along line DD in FIG. 5) of the second monitor light of the density detecting device in the first embodiment.

FIG. 5 is an explanatory diagram showing an arrangement state of first and second light emitters, first and second optical sensors, and first and second monitoring sensors in the first embodiment.

6A is a front view, FIG. 6B is a bottom view, and FIG. 6C is a plan view of a prism according to the first embodiment.

FIG. 7 is a sectional view taken along line EE of FIG. 1;

FIG. 8 is an explanatory diagram of a detection circuit in the first embodiment.

9A is a front view, FIG. 9B is a bottom view, and FIG. 9C is a plan view of a prism according to the second embodiment.

FIG. 10 is an explanatory diagram showing a configuration of a concentration detection device in a conventional example.

[Explanation of symbols]

 1. . . 9. concentration detector, . . 10. carbon particle concentration detector, . . First illuminant, 12; . . 12. first optical sensor; . . 1. first monitor sensor; . . 21. Oxidation degradation product concentration detector . . Second light emitter, 22. . . Second light sensor, 23. . . 30. second monitor sensor, . . First inspection light, 32. . . Second inspection light, 33. . . First monitor light, 34. . . 3. second monitor light; . . Prism, 40. . . 4. Wetted surface, . . Detection circuit,

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2G059 AA01 AA05 BB04 BB20 CC19 CC20 DD12 DD13 EE01 EE02 FF07 HH01 HH06 JJ12 KK01 LL03 MM01 MM05 MM20 NN05 NN06 NN08

Claims (7)

[Claims] A first illuminant that emits a first inspection light for detecting carbon particles in the oil; and a first light guide that is immersed in the oil and guides the first inspection light to a surface in contact with the oil. A light guide, a first light sensor for detecting a first inspection light totally reflected on the liquid contact surface of the first light guide, and a first detection connected to the first light sensor for determining a carbon particle concentration A carbon particle concentration detector having a circuit, a second luminous body for emitting a second inspection light having a different wavelength from the first inspection light for detecting oxidation degradation products in the oil, and immersed in the oil A second light guide for guiding the second inspection light to a liquid contact surface with the oil, a second optical sensor for detecting a second inspection light totally reflected on the liquid contact surface of the second light guide, A second detection circuit connected to the second optical sensor for determining the concentration of the oxidation degradation product. An oil deteriorating substance concentration detecting device comprising a degree detecting unit. 2. The method according to claim 1, wherein the first inspection light is infrared light having a wavelength of 0.7 to 1.1 μm, the second inspection light is infrared light having a wavelength of 0.95 to 7 μm, and The wavelength detector of claim 2, wherein the wavelength of the second inspection light is longer than the wavelength of the first inspection light. 3. The first light guide and the second light guide according to claim 1, wherein the first light guide and the second light guide are integral with each other, and are made of a material that transmits both the first inspection light and the second inspection light. An apparatus for detecting the concentration of degraded oil, characterized in that it is a prism. 4. The method according to claim 3, wherein the prism has the liquid contact surface at a cylindrical or prismatic tip.
The liquid contact surface includes a bottom surface portion formed of a plane substantially perpendicular to the incident direction of the first inspection light and the second inspection light, and first to fourth inclined surfaces sequentially surrounding the bottom surface portion. The first inspection light travels by being totally reflected on the first inclined surface, the bottom surface, and the third inclined surface, and the second inspection light is transmitted on the second inclined surface, the bottom surface, and the fourth inclined surface. Characterized in that it travels with total reflection of the oil. 5. The method according to claim 1, wherein:
The first detection circuit and the second detection circuit are configured to share one detection circuit, and the detection circuit includes the first detection circuit.
A device for detecting the concentration of degraded oil, wherein the device is electrically connected to both an optical sensor and the second optical sensor. 6. The method according to claim 1, wherein:
The carbon particle concentration detecting section has a first monitor sensor for detecting a first monitor light emitted together with the first inspection light from the first light emitter, and the first monitor sensor includes the first monitor sensor. A second monitor light that is electrically connected to the first detection circuit and detects a second monitor light emitted together with the second inspection light from the second luminous body; A second monitoring sensor electrically connected to the second detection circuit. The first detection circuit includes an output value from the first optical sensor and the first monitor sensor. The second detection circuit uses the output value from the second optical sensor and the output value from the second monitor sensor to determine the carbon particle concentration using the output value from Configured to determine the degradation product concentration The concentration detection apparatus of oil degradation products, characterized in that. 7. The method according to claim 1, wherein:
Liquid contact surfaces of the first light guide and the second light guide are covered with a cover member, and a cleaning member floating in oil is sealed inside the cover member. Has an oil inlet provided on the upstream side facing the oil flow and an oil outlet provided on the downstream side of the oil, and has an opening area of the oil outlet smaller than an opening area of the oil inlet. An oil concentration detection device for degraded oil, characterized in that it is made larger.