Monitoring device and monitoring method

Abstract

To provide a device and a method for monitoring that can monitor lubricant accurately with a simple configuration.SOLUTION: A monitoring device for monitoring lubricant of a bearing part includes: a detection device including a tip provided with a sensor part including an interval between an outer ring and an inner ring in the bearing part in the field of view, irradiating the lubricant flowing out from between the outer ring and the inner ring with light, and receiving reflection light from the lubricant on the basis of the light irradiation; and an arithmetic device for determining whether the lubricant deteriorates on the basis of at least one of the color information and light intensity of the reflection light that the detection device receives.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a lubricant monitoring device and a lubricant monitoring method. [Background technology]

[0002] Many different types of bearings are used in factory equipment in the steel industry and other industries. The bearings are equipped with a mechanism for automatically supplying lubricating oil to maintain lubrication during rotation. However, if the supply of lubricating oil is interrupted due to damage to the lubricating oil supply pipe or other equipment, the lubrication of the bearings is not maintained, and continued rotation and other operations can lead to damage to the bearings. As a result, repair work (replacement, etc.) must be carried out on the damaged bearings, which can result in the shutdown of the factory equipment. Therefore, continuous monitoring of the lubricating oil supply status at the bearings is necessary.

[0003] Furthermore, the lubricating oil supplied to the bearing deteriorates as it becomes contaminated with iron powder (wear particles) generated in the bearing and water seeping in from the outside due to repeated rotation of the bearing. If deteriorated lubricating oil is circulated and used repeatedly, not only will the lubrication of the bearing be impaired, but friction between parts can also cause damage to the equipment.

[0004] For this reason, methods for monitoring lubricating oil in bearings have been studied. Patent Document 1 discloses a technology for monitoring grease by measuring the visible light reflection characteristics of grease discharged from a bearing into a drain using an optical sensor installed in the drain. However, with the monitoring method disclosed in Patent Document 1, even if the grease discharged into the drain is monitored, there is a time lag between the time the grease travels from the bearing to the drain, making it impossible to accurately monitor the properties (deterioration) of the grease at the time it is in the bearing.

[0005] For example, Patent Document 2 discloses a technique for directly monitoring the grease sealed inside a bearing by inserting the tip of an iron particle sensor into the bearing. Also, Patent Document 3 discloses a technique for providing a sight glass on the side of the bearing and monitoring the lubricant inside the bearing through the sight glass using a sensor unit fixed to the sight glass. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2020-76379 [Patent Document 2] Japanese Patent Application Laid-Open No. 2011-202626 [Patent Document 3] Japanese Patent Application Laid-Open No. 2006-177715 [Patent Document 4] Japanese Patent Application Laid-Open No. 2017-110926 Summary of the Invention [Problem to be solved by the invention]

[0007] However, when the method of Patent Document 2 is applied, the iron particle sensor is fixed to the bearing and its tip is inserted into the bearing, which raises the risk of the iron particle sensor becoming misaligned or damaged due to bearing vibration, making continuous and stable monitoring of the grease difficult. Furthermore, when the method of Patent Document 3 is applied, the lubricant in the bearing is monitored through a sight glass, which means that the monitoring device and the lubricant in the bearing are separated, making it difficult to accurately monitor the properties of the lubricant. Another problem is that the configuration of the monitoring device becomes complicated because a window must be provided between the monitoring device and the bearing.

[0008] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a monitoring device and a monitoring method that can accurately monitor lubricating oil with a simple configuration. [Means for solving the problem]

[0009] [1] A monitoring device for monitoring lubricating oil in a bearing, the monitoring device having a sensor unit at its tip that has a field of view that covers the area between the outer ring and the inner ring in the bearing, a detection device that irradiates light onto the lubricating oil flowing out from between the outer ring and the inner ring and receives light reflected from the lubricating oil based on the light irradiation, and a calculation device that determines whether or not the lubricating oil has deteriorated based on at least one of the color information and light intensity of the reflected light received by the detection device. [2] The arithmetic device includes a memory unit that stores initial color information and initial light intensity of reflected light received when light is irradiated onto unused lubricating oil, a calculation unit that calculates the suitability of the lubricating oil flowing out from between the outer ring and the inner ring based on at least one of the initial color information and the initial light intensity stored in the memory unit and at least one of the color information and the light intensity received by the detection device, and a deterioration determination unit that compares the suitability calculated by the calculation unit with a preset threshold value for the suitability to determine whether or not the lubricating oil has deteriorated. [3] The monitoring device described in [1] or [2], wherein the calculation device further has an output unit that notifies the user of the lubricating oil if it determines that the lubricating oil has deteriorated. [4] The monitoring device described in [1] or [2], wherein the calculation device further has a concentration estimation unit that estimates the iron powder concentration or the water concentration in the lubricating oil based on at least one of the color information and the light intensity received by the detection device. [5] The monitoring device described in [1] or [2], wherein the detection device has a linear insertion portion that is arranged at an angle in the range of more than 0°C and less than 30°C relative to the axis of the bearing portion. [6] A monitoring method for monitoring lubricating oil in a bearing, comprising: providing a sensor unit at the tip thereof that has a field of view that covers the area between the outer ring and the inner ring in the bearing; irradiating light onto the lubricating oil flowing out from between the outer ring and the inner ring; receiving light reflected from the lubricating oil based on the light irradiation; and determining whether or not the lubricating oil has deteriorated based on at least one of the color information and light intensity of the received reflected light. [Effects of the Invention]

[0010] According to the present invention, lubricating oil can be accurately monitored with a simple configuration. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a schematic configuration diagram illustrating an example of a monitoring device. [Figure 2] FIG. 2 is an enlarged configuration diagram showing an example of a bearing portion and a detection device. [Figure 3] FIG. 10 is a diagram showing the results of determining whether or not a lubricating oil having an iron powder concentration has deteriorated. [Figure 4] FIG. 10 is a diagram showing the results of determining whether or not lubricating oil having a water concentration has deteriorated. DETAILED DESCRIPTION OF THE INVENTION

[0012] <Monitoring device> Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 shows the configuration of a monitoring device 10 according to this embodiment. Fig. 1 is a schematic diagram showing an example of the configuration of the monitoring device 10.

[0013] The monitoring device 10 is for monitoring the lubricating oil in the bearing portion 14 and includes a detection device 17 and a calculation device 19. In this embodiment, the lubricating oil also includes grease. The bearing portion 14 is housed in a bearing housing 11 having a peripheral wall 12, an end plate 13, and a partition wall 15. The bearing portion 14 includes an inner ring 14a, an outer ring 14b, and rollers 14d. The outer ring 14b has a flow path 14c.

[0014] The rollers 14d are rotatably provided between the outer ring 14b and the inner ring 14a. As shown in Fig. 1, a pair of rollers 14d is provided between the inner ring 14a and the outer ring 14b, sandwiching a gap 14e between them. A plurality of pairs of rollers 14d are provided in the circumferential direction of the bearing portion 14 along the gap between the inner ring 14a and the outer ring 14b.

[0015] The outer ring 14b is fixed to the peripheral wall 12. The inner ring 14a is provided on the surface of the roll end 22 of the roll 20, which rotates around the roll rotation axis R. Therefore, when the roll end 22 rotates together with the rotation of the roll main body 21 of the roll 20, the inner ring 14a also rotates. At this time, the outer ring 14b, which is fixed to the peripheral wall 12, does not rotate, and the rollers 14d rotate between the outer ring 14b and the inner ring 14a, allowing the roll 20 to rotate smoothly relative to the peripheral wall 12.

[0016] The peripheral wall 12 is configured to cover the circumferential side of the roll end portion 22 that rotates together with the roll main body portion 21. The peripheral wall 12 is also configured to have a bearing portion 14 therein. The peripheral wall 12 has an oil supply port 12a for supplying lubricating oil to the bearing portion 14. The peripheral wall 12 has an oil drain port 12b for draining lubricating oil used in the bearing portion 14.

[0017] In the embodiment shown in FIG. 1 , the upper side is the vertical upper side and the lower side is the vertical lower side. Therefore, when lubricating oil is supplied to the bearing unit 14, the lubricating oil is supplied from the oil inlet 12a located at the upper side of the drawing, and the lubricating oil reaches the gap 14e of the roller 14d via the flow path 14c of the outer ring 14b. Then, as the inner ring 14a rotates in accordance with the rotation of the roll end 22 and the roller 14d rotates, the lubricating oil accumulated in the gap 14e permeates between the roller 14d, the inner ring 14a, and the outer ring 14b. Then, as the bearing unit 14 operates, the used lubricating oil is gradually discharged from the oil drain port 12b. The lubricating oil discharged from the oil drain port 12b is filtered and then supplied again to the bearing unit 14 from the oil inlet 12a.

[0018] The end plates 13 have insertion holes 13a. The end plates 13 are provided on the opposite side of the roll end 22 from the roll body 21, and are configured to cover the end side of the roll end 22. Therefore, the roll end 22 is configured to be surrounded by the peripheral wall 12 that covers the circumferential side and the end plates 13 that cover the end side. Similarly, the bearing portions 14 are also configured to be surrounded by the peripheral wall 12 and the end plates 13.

[0019] As shown in Fig. 1, the partition wall 15 is provided between the bearing portion 14 and the roll body portion 21. Furthermore, a seal portion 15a provided on the partition wall 15 prevents the lubricating oil from leaking from the bearing portion 14 to the roll body portion 21. The bearing portion 14 is accommodated in a bearing housing 11 having a peripheral wall 12, an end plate 13, and the partition wall 15. In other words, the bearing housing 11 is configured to prevent the lubricating oil supplied to the bearing portion 14 from leaking to the outside.

[0020] A portion of the lubricating oil that is supplied from oil supply port 12a and passes through flow path 14c of outer ring 14b and accumulates in gap 14e of roller 14d flows out from between outer ring 14b and inner ring 14a into the space between bearing portion 14 and end plate 13. In this case, the leaked lubricating oil accumulates on the vertically lower side (bottom) of bearing housing 11 and is discharged from oil drain port 12b provided at the bottom in FIG. 1.

[0021] Next, the configuration of the detection device 17 will be described with reference to FIG. 2. FIG. 2 is an enlarged configuration diagram showing an example of the bearing 14 and the detection device 17. The detection device 17 has an insertion portion 17a and a sensor portion 17b. In the detection device 17, the insertion portion 17a has a linear configuration. The sensor portion 17b is provided at the tip of the insertion portion 17a. Then, as shown in FIG. 2, the insertion portion 17a is inserted into and fixed in the insertion hole 13a of the end plate 13, and the sensor portion 17b at the tip is brought into proximity with the bearing 14 to monitor the lubricating oil in the bearing 14.

[0022] The sensor unit 17b irradiates the target (lubricant) with light and receives light reflected from the target (lubricant) based on the irradiated light. The sensor unit 17b may irradiate white visible light as the irradiated light. Specifically, the sensor unit 17b includes in its field of view the area between the outer ring 14b and the inner ring 14a of the bearing unit 14, irradiates light onto the lubricant flowing out from between the outer ring 14b and the inner ring 14a into the bearing housing 11, and receives light reflected from the lubricant based on the irradiated light.

[0023] Here, if the linear insertion portion 17a is inserted into the bearing housing 11 through the peripheral wall 12 of the bearing housing 11, it becomes difficult for the field of view of the sensor portion 17b to include the area between the outer ring 14b and the inner ring 14a. For this reason, in this embodiment, the insertion portion 17a is inserted into the bearing housing 11 through an insertion hole 13a formed in an end plate 13 that constitutes the bearing housing 11.

[0024] The sensor unit 17b is positioned within a field of view that includes the gap between the outer ring 14b and the inner ring 14a and at a predetermined distance from the outermost roller area M of the roller 14d. In other words, by positioning the sensor unit 17b at a predetermined distance from the outermost roller area M, it is possible to prevent the sensor unit 17b from being caught in the bearing 14. Here, the outermost roller area M refers to the outermost area of ​​the roller 14d exposed between the outer ring 14b and the inner ring 14a, as shown in FIG. 2 . Note that if the sensor unit 17b is positioned far from the outermost roller area M, the amount of reflected light from the sensor unit 17b will be reduced due to divergence of the light emitted from the sensor unit 17b when the amount of lubricating oil flowing out from between the outer ring 14b and the inner ring 14a is small (e.g., between oil supply intervals), making accurate measurement difficult. Therefore, the "predetermined distance" is preferably within 1 cm. On the other hand, if the distance between sensor part 17b and the object to be measured (flowing lubricant) is too close, the amount of light received by sensor part 17b will fluctuate, so it is preferable that the "predetermined distance" is 0.1 cm or more.

[0025] The sensor unit 17b is preferably positioned so that its field of view includes the area between the outer ring 14b and the inner ring 14a and the lubricating oil flowing from the surface of the roller 14d. Specifically, the sensor unit 17b is preferably positioned so that its field of view includes the area vertically below the extension of the roller rotation axis P of the roller 14d and above the outermost part M of the roller.

[0026] Furthermore, in the bearing housing 11, the lubricating oil that flows out from between the outer ring 14b and the inner ring 14a moves vertically, and therefore accumulates on the vertically lower side (bottom) of the bearing housing 11. For this reason, if the sensor unit 17b is placed on the bearing unit 14 located on the vertically lower side (bottom) of the bearing units 14 (inner ring 14a, outer ring 14b, rollers 14d) shown in FIG. 1, the lubricating oil that has accumulated on the vertically lower side (bottom) will also be included in the field of view, and it will be difficult to accurately determine the deterioration of the lubricating oil. For this reason, it is preferable to place the sensor unit 17b opposite the bearing unit 14 (inner ring 14a, outer ring 14b, rollers 14d) located on the vertically upper side (top) of the bearing housing 11.

[0027] Furthermore, it is preferable that the sensor unit 17b be disposed at a predetermined angle with respect to the angle of view of the bearing unit 14. Specifically, it is preferable that the linear insertion unit 17a be disposed at an angle greater than 0°C and less than 30°C with respect to the axis of the bearing unit 14, i.e., a line parallel to the roll rotation axis R. In this embodiment, as shown in FIG. 2, the insertion unit 17a is disposed at an angle θ greater than 0°C and less than 30°C with respect to a perpendicular line T parallel to the roll rotation axis R. Here, the perpendicular line T is a perpendicular line to a straight line L connecting the outermost roller surface M of the roller 14d provided between the outer ring 14b and the inner ring 14a and the outermost outer ring surface N of the outer ring 14b.

[0028] By positioning the linear insertion portion 17a at a predetermined angle θ, the field of view of the sensor portion 17b relative to the bearing portion 14 also has the predetermined angle θ. This allows light to be irradiated over a wide range onto the bearing portion 14, and light reflected from a wide field of view can be received. Note that if the predetermined angle θ exceeds 30°, the light irradiation range becomes too wide, increasing the amount of light reflected from equipment components other than the lubricant, which may make it difficult to accurately monitor the lubricant.

[0029] Next, the configuration of the arithmetic device 19 will be described with reference to Fig. 1. The arithmetic device 19 has a storage unit 19a, a calculation unit 19b, a deterioration determination unit 19c, a concentration estimation unit 19d, and an output unit 19e. It is sufficient for the arithmetic device 19 to have at least one of the calculation unit 19b and the concentration estimation unit 19d. The arithmetic device 19 determines whether or not the lubricant has deteriorated based on at least one of color information and light intensity of the reflected light received by the sensor unit 17b of the detection device 17.

[0030] When the lubricating oil is repeatedly used in the bearing 14, it deteriorates due to the inclusion of iron particles (wear particles) generated in the bearing 14 and moisture infiltrating from the outside. The iron particles (wear particles) and moisture mixed into the lubricating oil have properties that cause changes in the reflection and scattering of light. Therefore, when determining whether the lubricating oil has deteriorated, the lubricating oil is irradiated with light, and the degree of contamination by iron particles, etc. in the lubricating oil, i.e., whether the lubricating oil has deteriorated, can be determined based on at least one of the color information and light intensity of the reflected light obtained by the light irradiation. For example, when iron particles are mixed into grease, which is a lubricating oil, the color information of the reflected light obtained by the light irradiation becomes closer to "black," the light intensity of the reflected light decreases, and the wavelength shifts toward shorter wavelengths. On the other hand, when moisture is mixed into the grease, the color information of the reflected light obtained by the light irradiation becomes "light," the light intensity of the reflected light increases, and the wavelength shifts toward longer wavelengths.

[0031] The memory unit 19a stores initial color information and initial light intensity of reflected light received when light is irradiated onto unused lubricating oil. The calculation unit 19b is communicably connected to the sensor unit 17b of the detection device 17. The calculation unit 19b receives information regarding the color information and light intensity of the reflected light received by the sensor unit 17b from the sensor unit 17b. The calculation unit 19b calculates the suitability of the lubricating oil flowing out from between the outer ring 14b and the inner ring 14a based on at least one of the initial color information and initial light intensity stored in the memory unit 19a and at least one of the color information and light intensity received by the sensor unit 17b. The deterioration determination unit 19c then compares the suitability of the lubricating oil calculated by the calculation unit 19b with a preset suitability threshold to determine whether the lubricating oil has deteriorated. The output unit 19e then issues a notification of the deterioration if the deterioration determination unit 19c determines that the lubricating oil has deteriorated. The threshold value may be determined based on the relationship between the limit value of the iron powder concentration or the moisture concentration and at least one of the color information and the light intensity of the lubricant oil, based on past operational results. The threshold value may be stored in advance in the storage unit 19a, similar to the initial color information and the initial light intensity. Here, when the degree of conformance is calculated based on the initial color information and the color information of the reflected light, the calculation is performed by comparing the RGB values ​​of each. When the degree of conformance is calculated based on the initial light intensity and the light intensity of the reflected light, the calculation is performed by comparing the wavelength distributions of the light intensity of each. The degree of conformance may be calculated using a method for determining the degree of conformance of light, such as reflected light (see Patent Document 4).

[0032] The iron particle concentration or water concentration of the lubricant may be used to determine whether the lubricant has deteriorated. In this case, the concentration estimation unit 19d may be communicably connected to the sensor unit 17b. The concentration estimation unit 19d may estimate the iron particle concentration or water concentration of the lubricant based on at least one of the color information and light intensity of the light received by the sensor unit 17b. The deterioration determination unit 19c may then compare the iron particle concentration or water concentration of the lubricant calculated by the concentration estimation unit 19d with a preset threshold value for the iron particle concentration or water concentration to determine whether the lubricant has deteriorated. The output unit 19e may notify the deterioration when the deterioration determination unit 19c determines that the lubricant has deteriorated. The threshold value may be determined from a limit value of the iron particle concentration or water concentration based on past operational performance. The threshold value may be stored in advance in the memory unit 19a.

[0033] In this case, a relational expression between the iron particle concentration or water concentration in the lubricating oil and the color information or light intensity of the reflected light may be created in advance. Specifically, first, multiple lubricating oils with different iron particle concentrations or water concentrations are prepared, and the color information or light intensity of the reflected light obtained by irradiating the multiple lubricating oils with light is measured. Then, combination patterns of the measured iron particle concentration or water concentration and the color information or light intensity of the reflected light are stored, and a relational expression between the measured iron particle concentration or water concentration and the color information or light intensity of the reflected light is created. The iron particle concentration or water concentration of the lubricating oil being measured may be estimated by substituting the color information or light intensity of the reflected light from the newly measured lubricating oil into the created relational expression. The relational expression between the measured iron particle concentration or water concentration and the color information or light intensity of the reflected light may be stored in advance in the storage unit 19a.

[0034] <Monitoring method> In consideration of the above configuration, the monitoring method of the present invention is a monitoring method for monitoring the lubricating oil in the bearing portion 14, in which a sensor portion 17b is provided at the tip thereof, the sensor portion 17b having a field of view that covers the area between the outer ring 14b and the inner ring 14a in the bearing portion 14, light is irradiated onto the lubricating oil flowing out from between the outer ring 14b and the inner ring 14a, and light reflected from the lubricating oil based on the irradiated light is received, and whether or not the lubricating oil has deteriorated is determined based on at least one of the color information and light intensity of the reflected light received.

[0035] As described above, according to the monitoring device and monitoring method of this embodiment, by inserting the detection device 17 inside the bearing housing 11 and arranging the sensor part 17b of the detection device 17 at a position that is a predetermined distance from the bearing part 14, it is possible to accurately monitor the lubricating oil flowing out from the bearing part 14 with a simple configuration.

[0036] In particular, in this embodiment, the detection device 17 is fixed to the end plate 13 of the bearing housing 11 and monitors the lubricating oil flowing out from between the outer ring 14b and the inner ring 14a. Therefore, compared to a configuration in which the detection device 17 is fixed to the bearing portion 14 and monitors the lubricating oil inside the bearing portion 14, it is possible to prevent the detection device 17 (sensor portion 17b) from being caught in the bearing portion 14. Furthermore, even if vibrations occur in the bearing portion 14 due to the rotational movement of the roll end portion 22, it is possible to prevent the detection device 17 (sensor portion 17b) from shifting in position.

[0037] In this embodiment, the bearing portion 14 is described as having a roller 14d, but the configuration of the bearing portion is not limited, and other rolling bearings such as ball bearings, or sliding bearings other than rolling bearings, can also be applied to the present invention.

[0038] Furthermore, in this embodiment, as shown in FIG. 1, a configuration has been described in which the bearing portion 14 is provided at the roll end portion 22 of the roll 20 whose roll rotation axis R extends horizontally. However, the present invention is not limited to a configuration in which the roll 20 extends in a direction in which the roll rotation axis R extends vertically, and is also applicable.

[0039] Furthermore, although this embodiment has been described as being configured to determine whether or not the lubricant has deteriorated based on at least one of the color information and light intensity of the reflected light received by the detection device 17, it is preferable to calculate the degree of compatibility based on both the color information and light intensity of the reflected light. By determining the deterioration of the lubricant based on both the light intensity and color information of the light reflected from the lubricant, it becomes possible to determine the deterioration based on minute changes in the iron powder concentration and water concentration of the lubricant. [Example]

[0040] The results of monitoring the presence or absence of deterioration of the lubricating oil in the bearing portion 14 using the monitoring device and monitoring method according to the present invention will be described.

[0041] First, we verified whether it is possible to determine whether a lubricant containing iron powder is deteriorated. A sample of unused lubricant containing 0% iron powder by mass was prepared, and several used lubricant samples containing varying iron powder concentrations were prepared. The unused lubricant was then irradiated with light and the reflected light was received. The initial color information and initial light intensity of the received light were stored in the computing device 19. Several lubricants containing different iron powder concentrations were then supplied to the bearing 14, and the deterioration of the lubricant was determined. The initial color information and initial light intensity of the unused lubricant containing 0% iron powder by mass were used as a reference, and the degree of conformance with at least one of the color information and light intensity obtained from the other samples containing iron powder was calculated. The degree of conformance at the limit of the iron powder concentration (0.6% iron powder by mass) was set as a threshold. In this case, the compatibility of the unused lubricating oil was 1000, and the compatibility (threshold) at the limit value of the iron powder concentration was 8000. The threshold was determined based on the past operational results from the relationship between the limit value of the iron powder concentration and at least one of the color information and light intensity of the lubricating oil.

[0042] Figure 3 shows the results of determining whether or not lubricating oil with an iron particle concentration had deteriorated. As shown in Figure 3, as the iron particle concentration of the lubricating oil increased, the degree of conformance with the reference unused lubricating oil decreased. When a sample with an iron particle concentration of 0.6 mass % was tested, the degree of conformance fell below the threshold value (800), and this was reported by the output unit 19e.

[0043] Next, we verified whether it is possible to determine whether a lubricant has deteriorated when water is present in the lubricant. A sample of unused lubricant with a water concentration of 0% by mass was prepared, and several used lubricant samples with varying water concentrations were prepared. The unused lubricant was then irradiated with light and the reflected light was received, and the initial color information and initial light intensity of the received light were stored in the computing device 19. Subsequently, several lubricants with different water concentrations were supplied to the bearing 14, and the deterioration of the lubricant was determined. The initial color information and initial light intensity of the unused lubricant with a water concentration of 0% by mass were used as a reference, and the degree of conformance with at least one of the color information and light intensity obtained from the other samples with different water concentrations was calculated, and the degree of conformance at the limit value of the water concentration (a water concentration of 10% by mass) was set as a threshold. The degree of conformance for the unused lubricant was 1000, and the degree of conformance (threshold) at the limit value of the water concentration was 700. In this example as well, the threshold value was determined based on the relationship between the limit value of the water concentration and at least one of the color information and light intensity of the lubricating oil, based on past operational results.

[0044] Figure 4 shows the results of determining whether or not lubricating oils with different water concentrations have deteriorated. As shown in Figure 4, as the water concentration of the lubricating oil increases, the degree of conformance with the reference unused lubricating oil decreases. When a sample with a water concentration of 10% by mass was tested, the degree of conformance fell below the threshold value (700), and this was reported by the output unit 19e.

[0045] Although the samples used in the examples were virgin lubricating oil with iron powder concentration and virgin lubricating oil with water concentration, the present invention is not limited to the samples used in the examples and can be applied to any lubricating oil. The threshold value used to determine deterioration can also be appropriately set according to the lubricating oil to be applied. [Explanation of symbols]

[0046] 10 Monitoring equipment 11 Bearing box 12 Surrounding wall 12a Fuel filler 12b Oil drain port 13 End plate 13a Insertion hole 14 Bearing section 14a Inner Circle 14b outer ring 14th Coro 15 Partition Wall 15a Seal part 17 Detection equipment 17a Insertion part 17b Sensor section 19 Arithmetic unit 19a Storage section 19b Calculation part 19c Deterioration judgment section 19d Concentration estimation part 19e Output section 20 rolls 21 Roll body 22 Roll end L straight line M outermost roller N Outermost part of outer ring P Roller rotation axis R Roll rotation axis

Claims

1. A monitoring device for monitoring lubricating oil in a bearing portion, a detection device that has a sensor unit at its tip that has a field of view that covers the area between the outer ring and the inner ring of the bearing, that irradiates light toward the lubricating oil flowing out from between the outer ring and the inner ring, and that receives light reflected from the lubricating oil based on the light irradiation; a computing device that measures color information or light intensity of reflected light based on light irradiation of a plurality of lubricating oils having different iron or water concentrations in advance, creates a relational expression between the iron or water concentration and the color information or light intensity of the reflected light from a combination pattern of the iron or water concentration and the color information or light intensity of the reflected light, estimates the iron or water concentration of the lubricating oil by substituting at least one of the color information and light intensity of the reflected light received by the detection device into the relational expression, and compares the estimated iron or water concentration with a limit value of the iron or water concentration determined based on past operating results, thereby determining whether the lubricating oil has deteriorated; A monitoring device comprising:

2. The monitoring device according to claim 1 , further comprising an output unit that, when it is determined that the lubricating oil has deteriorated, issues a notification to that effect.

3. 2. The monitoring device according to claim 1, wherein the detection device has a linear insertion portion disposed at an angle greater than 0 degrees and equal to or less than 30 degrees relative to the axis of the bearing portion.

4. A monitoring method for monitoring lubricating oil in a bearing, comprising: a sensor unit having a field of view that covers the area between the outer ring and the inner ring of the bearing unit is provided at the tip thereof, and light is irradiated toward the lubricating oil flowing out from between the outer ring and the inner ring, and light reflected from the lubricating oil based on the light irradiation is received; A monitoring method comprising: measuring in advance the color information or light intensity of reflected light based on the irradiation of light onto a plurality of lubricating oils having different iron powder concentrations or water concentrations; creating a relational expression between the iron powder concentration or water concentration and the color information or light intensity of the reflected light from a combination pattern of the iron powder concentration or water concentration and the color information or light intensity of the reflected light; substituting at least one of the color information and light intensity of the received reflected light into the relational expression to estimate the iron powder concentration or water concentration of the lubricating oil; and comparing the estimated iron powder concentration or water concentration with a limit value for the iron powder concentration or water concentration determined based on past operating results to determine whether the lubricating oil has deteriorated.

Images