JP7375598B2 - Diagnostic system for rolling bearings and rotational support equipment with diagnostic system - Google Patents

Description

The present invention relates to a diagnostic system for diagnosing the condition of a rolling bearing, and a rotation support device equipped with this diagnostic system.

FIG. 10 shows a rotary support device with a thermometer described in Japanese Unexamined Patent Publication No. 2003-49832 (Patent Document 1). The rotation support device 100 with a thermometer is for rotatably supporting the wheels of a railway vehicle with respect to a suspension device, and includes an axle 101 connected and fixed to the center of the wheel, and a cylinder supported and fixed to the suspension device. A housing 102 having a shape, a double-row tapered roller bearing 103 for rotatably supporting an axle 101 inside the housing 102, and a radiation thermometer 104 are provided.

The double-row tapered roller bearing 103 includes an outer ring 105, a pair of inner rings 106, a plurality of tapered rollers 107, and an inner ring spacer 108.

The outer ring 105 has a double row outer ring raceway 109 on its inner peripheral surface. Each of the double row outer ring raceways 109 has a concave conical shape, and is inclined in such a direction that the inner diameter increases as the distance from each other in the axial direction increases. The outer ring 105 is fitted inside the housing 102 and does not rotate during use.

Each of the pair of inner rings 106 has a conical convex inner ring raceway 110 on its outer peripheral surface, and a large collar part 111 that protrudes radially outward from a portion adjacent to the large diameter side of the inner ring raceway 110 in the axial direction. have The pair of inner rings 106 are disposed coaxially with the outer ring 105 on the radially inner side of the outer ring 105, with their small-diameter end faces abutting each other with a cylindrical inner ring spacer 108 interposed therebetween. The pair of inner ring 106 and inner ring spacer 108 are fitted onto the axle 101 and rotate together with the axle 101 during use.

The tapered rollers 107 are arranged in each row between a double-row outer ring raceway 109 provided on the inner peripheral surface of the outer ring 105 and a double-row inner ring raceway 110 provided on the outer peripheral surface of the pair of inner rings 106. A plurality of them are arranged in a state where they are rotatably held by a cage 112. Further, in this state, each large-diameter side end surface 113 of the tapered roller 107 faces the axially inner surface 114 of the large flange portion 111. Note that the axially inner side surface 114 of the large flange portion 111 is the side surface on the inner ring raceway 110 side among the axially both side surfaces of the large flange portion 111 . Contact portions (rolling contact portions, sliding contact portions) between each surface of the tapered rollers 107 and the mating surfaces (outer ring raceway 109, inner ring raceway 110, inner surface of pocket of retainer 112, and axially inner surface 114 of large flange portion 111) part) is lubricated with grease.

The radiation thermometer 104 radially penetrates the axial center portions of the housing 102 and the outer ring 105, and has a detection portion (light receiving portion) provided at its tip facing the outer peripheral surface of the inner ring spacer 108. In this state, it is supported by the housing 102 and the outer ring 105. In this state, the radiation thermometer 104 can measure the temperature of the inner ring spacer 108 based on the detection unit detecting infrared rays emitted from the inner ring spacer 108.

In the rotary support device 100 with a thermometer having the above configuration, the temperature of the inner ring spacer 108, which is disposed adjacent to the inner ring 106 where the temperature tends to be the highest during operation, and which undergoes the same temperature change as the inner ring 106, is controlled. , can be measured by a radiation thermometer 104. Therefore, if the temperature of the double-row tapered roller bearing 103 rises excessively for some reason, a sign of seizure can be detected based on measuring this temperature with the radiation thermometer 104. Therefore, maintenance of the double-row tapered roller bearing 103 can be performed before seizure occurs.

Japanese Patent Application Publication No. 2003-49832

The above-described rotary support device 100 with a thermometer has room for improvement in terms of more accurately detecting signs of burn-in.

That is, during operation of the rotary support device 100 with a thermometer, oxidized wear particles are generated at the contact portions (rolling contact portions, sliding contact portions) between each surface of the tapered roller 107 and the mating surface. In particular, since the large-diameter side end surfaces 113 of each tapered roller 107 are in sliding contact with the axially inner surface 114 of the large flange portion 111 in a strongly pressed state, oxidized wear particles are likely to be generated. Since oxidized wear particles have high hardness, they act like an abrasive in these sliding contact areas, easily promoting the generation of further oxidized wear particles, and worsening the generatrix shape and roughness of the sliding contact areas. Therefore, it may cause burn-in. The oxidized wear particles generated in this way mix into the lubricant grease, and as the usage time passes, the content of oxidized wear particles in the grease (the degree of contamination of the grease) increases. The lubrication condition gradually deteriorates, and the sliding contact area generates more heat than when the grease is new, increasing the possibility of seizure. In other words, in order to more accurately detect signs of seizure, it is necessary to consider not only the temperature but also the state of occurrence of oxidized wear particles.

In view of the above-mentioned circumstances, the present invention aims to realize a structure that can more accurately detect signs of seizure in a rolling bearing.

The rolling bearing diagnostic system of the present invention includes a pair of bearing rings, a plurality of rolling elements arranged between the pair of bearing rings, and a surface and a mating surface of each of the plurality of rolling elements. This is a system for diagnosing the condition of rolling bearings, which includes grease that lubricates the contact parts with the bearing.
In particular, the rolling bearing diagnostic system of the present invention is characterized in that the spectral brightness of wavelength components in a predetermined range of light passing through the grease changes due to the temperature of the rolling bearing and contamination of the grease; It has a function to determine whether there is a sign of burn-in by using

One aspect of the rolling bearing diagnostic system of the present invention includes a detection section, and the detection section is brought into contact with a part to be measured of a member whose temperature increases and is covered with the grease as the rolling bearing operates. and a contact thermometer for measuring the contact temperature of the point to be measured, and a light receiving section, the light receiving section being opposed to the point to be measured through the grease, and the radiation of the point to be measured. The present invention includes a radiation thermometer that measures temperature, and a diagnostic device that determines whether or not there is a sign of seizure in the rolling bearing based on the difference between the contact temperature and the radiation temperature.

One aspect of the rolling bearing diagnostic system of the present invention includes: a thermometer that measures the temperature of a part of a member whose temperature increases and is covered with the grease as the rolling bearing operates; A light emitter and a light receiver are arranged opposite to each other with the grease covering the spot in between, the temperature of the spot to be measured is measured by the thermometer, and the wavelength components in a predetermined range of the light received by the light receiver are measured. and a diagnostic device that determines whether there is a sign of burn-in based on spectral brightness.

In one aspect of the rolling bearing diagnostic system of the present invention, the rolling bearing includes an outer ring having a conical concave outer ring raceway on an inner circumferential surface, a conical convex inner ring raceway on the outer circumferential surface, and an outer ring raceway having a conical convex inner ring raceway on the outer circumferential surface, An inner ring having a large flange protruding radially outward from a portion adjacent to the large diameter side of the inner ring raceway, and an inner ring disposed between the outer ring raceway and the inner ring raceway, and the large diameter side end face of each inner ring having a large flange protruding outward in the radial direction. A tapered roller bearing comprising a plurality of tapered rollers facing each other on an axially inner surface of the roller, and grease for lubricating a contact portion between the surface of each of the plurality of tapered rollers and a mating surface, The part to be measured is the outer circumferential surface of the large flange.

In one aspect of the rolling bearing diagnostic system of the present invention, the presence or absence of a sign of seizure is determined by utilizing a change in the spectral brightness of a component with a wavelength of 17 μm or more and 23 μm or less of the light that has passed through the grease. It has the function of

A rotational support device with a diagnostic system of the present invention includes a rotational support device including a rolling bearing, and a rolling bearing diagnostic system that diagnoses the condition of the rolling bearing.
The rolling bearing includes a pair of bearing rings, a plurality of rolling elements arranged between the pair of bearing rings, and a contact portion between a surface of each of the plurality of rolling elements and a mating surface. A lubricating grease is provided.
The rolling bearing diagnostic system is the rolling bearing diagnostic system of the present invention.

According to the present invention, signs of seizure in a rolling bearing can be detected more accurately.

FIG. 1 is a sectional view of a rotation support device according to a first example of the embodiment. FIG. 2 is an enlarged view of section A in FIG. FIG. 3 is a log-log graph showing the spectrum of light emitted from a black body using temperature as a parameter. FIG. 4 is a block diagram illustrating a function for determining a sign of burn-in that is included in the diagnostic device of the first example of the embodiment. FIG. 5 is a diagram corresponding to FIG. 2, showing a second example of the embodiment. FIG. 6 is a view taken along arrow B in FIG. FIG. 7 is a view taken along arrow C in FIG. FIG. 8 is a block diagram illustrating a function for determining a sign of burn-in that is included in the diagnostic device according to the second example of the embodiment. FIG. 9 is an image diagram showing the criteria for determining a sign of burn-in in the second example of the embodiment. FIG. 10 is a sectional view showing a conventionally known rotary support device with a thermometer.

[First example of embodiment]
A first example of the embodiment will be described using FIGS. 1 to 4.
The rotation support device 1 with a diagnostic system of this example includes a rotation support device 2 including a pair of tapered roller bearings 6a and 6b, and a diagnosis system 3.

The rotation support device 2 is an outer ring rotating type wheel support device for driven wheels of large vehicles such as trucks and buses, and includes an axle 4, a hub 5, and a pair of tapered roller bearings 6a, 6b. Be prepared.

In the following explanation, the outer side in the vehicle width direction is the left side in FIG. 2 is the right side in FIG. 1 corresponding to the center side in the width direction of the vehicle when it is assembled to the vehicle.

The axle 4 constitutes a suspension device, has a cylindrical shape, and does not rotate during use. The axle 4 has cylindrical fitting surfaces 7a and 7b arranged coaxially with each other at two positions spaced apart in the axial direction on the outer peripheral surface. The fitting surface portion 7a on the outer side in the vehicle width direction has a smaller outer diameter than the fitting surface portion 7b on the inner side in the vehicle width direction. Further, the axle 4 has a stepped surface 8 facing outward in the vehicle width direction at a position adjacent to the inner side in the vehicle width direction of the fitting surface portion 7b on the inner side in the vehicle width direction.

The hub 5 has a cylindrical shape and is arranged around the axle 4 coaxially with the axle 4 . The hub 5 has cylindrical fitting surfaces 9a and 9b arranged coaxially with each other on the inner circumferential surface of both sides in the axial direction. The hub 5 has a stepped surface 10a facing outward in the vehicle width direction at a position adjacent to the inner side in the vehicle width direction of the fitting surface portion 9a on the outer side in the vehicle width direction, and has a stepped surface 10a facing outward in the vehicle width direction. A step surface 10b facing inward in the vehicle width direction is provided at a position adjacent to the outside in the width direction. The hub 5 also has a flange portion 11 that protrudes radially outward from an axially intermediate portion and to which a wheel and a braking rotating member, which are rotating bodies, are fixed during use.

The pair of tapered roller bearings 6a and 6b are for rotatably supporting the hub 5 with respect to the axle 4, and are spaced apart in the axial direction between the outer peripheral surface of the axle 4 and the inner peripheral surface of the hub 5. In addition, they are arranged so that the directions of their contact angles are back-to-back. When each of the pair of tapered roller bearings 6a and 6b is in use, the lower side (ground side, vertically lower side) is the area where the radial load due to the vehicle weight is applied, and the upper side is the side where the radial load due to the vehicle weight is applied. Become the sphere side. Therefore, in each of the pair of tapered roller bearings 6a and 6b, the lower end position, which is the circumferential center position on the lower side, is the maximum load position in the load zone.

Each of the tapered roller bearings 6a, 6b has an inner ring 12a, 12b which is a bearing ring (stationary ring) that does not rotate during use, and an outer ring 13a, 13b which is a bearing ring (rotating ring) that rotates during use. It includes a plurality of tapered rollers 14a, 14b which are moving bodies, and grease G (not shown) which is a lubricant.

Each of the inner rings 12a and 12b is made of bearing steel, carburized steel, or medium carbon steel. Each of the inner rings 12a and 12b has a conical convex inner ring raceway 15a and 15b on the outer circumferential surface, and a large flange portion that protrudes radially outward from a portion adjacent to the large diameter side of the inner ring raceway 15a and 15b in the axial direction. 16a, 16b, and small flanges 17a, 17b that protrude radially outward from portions adjacent to the small diameter side of the inner ring raceways 15a, 15b in the axial direction. The outer circumferential surfaces 20a, 20b of the large flange portions 16a, 16b are constituted by cylindrical surfaces. In particular, in this example, regarding the tapered roller bearing 6a on the outside in the vehicle width direction, the color of the outer circumferential surface 20a of the large flange portion 16a is black. For this reason, in this example, the outer peripheral surface 20a of the large flange portion 16a is subjected to a blackening treatment such as black alumite treatment (painting by spraying or the like). In addition, when carrying out this invention, it is not necessarily necessary to perform a blackening process on the outer peripheral surface 20a of the large flange part 16a, and the outer peripheral surface 20a should just be a non-shining surface. Specifically, for example, the color of the outer circumferential surface 20a of the large flange portion 16a can be made black by leaving a black crust (oxide film) produced by hot working or heat treatment.

Each of the outer rings 13a and 13b is made of bearing steel, carburized steel, or medium carbon steel. Each of the outer rings 13a and 13b has a concave outer ring raceway 18a and 18b on the inner peripheral surface.

Each of the plurality of tapered rollers 14a, 14b is made of bearing steel, carburized steel, or ceramics. Each of the plurality of tapered rollers 14a, 14b is disposed between the inner ring raceway 15a, 15b and the outer ring raceway 18a, 18b in a state where it is rotatably held by retainers 19a, 19b. Further, in this state, the large-diameter side end surfaces 21a, 21b of the plurality of tapered rollers 14a, 14b are opposed to the axially inner surfaces 22a, 22b of the large flanges 16a, 16b. The axially inner surfaces 22a and 22b of the large flange portions 16a and 16b are the side surfaces on the inner ring raceway 15a and 15b side among the axially opposite side surfaces of the large flange portion 16a (16b).

The contact portion between the surfaces of each of the plurality of tapered rollers 14a, 14b constituting the tapered roller bearings 6a, 6b and the other surface, specifically, the outer circumferential surface of each of the plurality of tapered rollers 14a, 14b and the inner raceway. 15a, 15b and the outer ring raceways 18a, 18b, the large diameter side end surfaces 21a, 21b of the plurality of tapered rollers 14a, 14b, and the axially inner surfaces 22a, 22b of the large flanges 16a, 16b. The sliding contact portions and the sliding contact portions between the surfaces of the plurality of tapered rollers 14a, 14b and the inner surfaces of the respective pockets of the cages 19a, 19b are each lubricated with grease G.

As shown in FIG. 1, the tapered roller bearing 6a on the outside in the vehicle width direction has an inner ring 12a externally fitted on the fitting surface 7a of the axle 4, and an outer ring 13a fitted internally on the fitting surface 9a of the hub 5. There is. In this state, the outer surface of the inner ring 12a in the vehicle width direction is in contact with the inner surface of the nut 23 screwed to the outer end of the axle 4 in the vehicle width direction, and the inner surface of the outer ring 13a in the vehicle width direction The side surface is in contact with the stepped surface 10a of the hub 5. On the other hand, in the tapered roller bearing 6b on the inner side in the vehicle width direction, the inner ring 12b is fitted onto the fitting surface 7b of the axle 4, and the outer ring 13b is fitted inside the fitting surface 9b of the hub 5. In this state, the inner surface of the inner ring 12b in the vehicle width direction is in contact with the step surface 8 of the axle 4, and the outer surface of the outer ring 13b in the vehicle width direction is in contact with the step surface 10b of the hub 5.

During operation of the rotational support device 2 having the above configuration, when the hub 5 and the outer rings 13a, 13b rotate with respect to the axle 4 and the inner rings 12a, 12b, the tapered rollers 14a, 14b each rotate on the inner ring raceway 15a, 15b and the outer ring raceways 18a, 18b, while supporting the radial load and axial load, it rotates (rotates) about its own central axis, and rotates (rotates) about the central axis of the tapered roller bearings 6a, 6b. revolution). At this time, a component force acting on each of the tapered rollers 14a and 14b in a direction to move it toward the larger diameter side is based on the radial load, axial load, and centrifugal force accompanying the revolution. Therefore, the large-diameter side end surfaces 21a, 21b of the tapered rollers 14a, 14b are strongly pressed into sliding contact with the axially inner surfaces 22a, 22b of the large flanges 16a, 16b.

Therefore, among the contact portions between the respective surfaces of the tapered rollers 14a, 14b constituting the tapered roller bearings 6a, 6a and their mating surfaces, the large diameter side end surfaces 21a, 21b of the tapered rollers 14a, 14b and the large flange portion 16a. , 16b and the axially inner surfaces 22a, 22b tend to generate more frictional heat than other contacting parts, and if the temperature rises excessively due to this frictional heat, the oil film may break. may occur, resulting in burn-in.

In addition, the sliding contact portions between the large-diameter end surfaces 21a, 21b of the tapered rollers 14a, 14b and the axially inner surfaces 22a, 22b of the large flanges 16a, 16b are more prone to wear than other contact portions. . Then, the hard oxidized wear particles generated by such wear are mixed into the grease G, and as the usage time passes, the content of oxidized wear particles in the grease G (the degree of contamination of the grease G) increases. As time goes on, the lubrication state of the sliding contact portion gradually deteriorates, and compared to when the grease G is new, the sliding contact portion generates more heat, increasing the possibility of seizure.

The diagnostic system 3 is a system for diagnosing the condition of the tapered roller bearing 6a on the outside in the vehicle width direction, and includes a contact thermometer 24, a radiation thermometer 25, and a diagnostic device 26.

The contact thermometer 24 has a detection section at its tip that is brought into contact with a measurement target location of an object. Then, the temperature (contact temperature, actual temperature) of the measured location is measured based on the detection unit being brought into contact with the measured location. In this example, a thermocouple is used as the contact thermometer 24. However, when implementing the present invention, a contact thermometer other than a thermocouple can also be used as the contact thermometer 24.

The radiation thermometer 25 has a light-receiving section at its tip that faces the measurement target part of the object in a non-contact manner. Then, the light emitted from the measurement point is received by the light receiving section, and the temperature (radiant temperature) of the measurement point is calculated from the frequency distribution of the received light and the spectral brightness (light amount, light intensity) for each frequency. Measure.

The contact thermometer 24 and the radiation thermometer 25 measure the temperature at a measurement point P of the inner ring 12a, which is a member whose temperature increases as the rotation support device 2 operates and is covered with grease G. In this example, the measurement point P is one point in the circumferential direction of the outer peripheral surface 20a of the large flange portion 16a, which is a black surface. During operation of the rotation support device 2, the temperature of the inner ring 12a tends to be higher in the loaded area than in the non-loaded area. For this reason, it is preferable that the measured point P is a point whose phase in the circumferential direction matches the load zone. In this example, the measured point P is a point where the temperature of the inner ring 12a is most likely to be the highest during operation of the rotary support device 2, and whose phase in the circumferential direction matches the maximum load position (lower end position) of the load zone. That is, the measurement point P is a circumferential portion located at the lower end of the outer circumferential surface 20a of the large flange portion 16a. The grease G that lubricates the sliding contact portion between the large-diameter side end surface 21a of each of the plurality of tapered rollers 14a and the axially inner surface 22a of the large flange portion 16a is used to prevent the plurality of tapered rollers 14a from rolling (rotation and revolution). ) due to the pumping effect, it climbs onto the measured point P and covers the measured point P (particularly the end on the axially inner surface 22a side of the large flange portion 16a in the axial direction).

The contact thermometer 24 detects the temperature of the measured point P by bringing the detection section provided at the tip into contact with the measured point P (in the illustrated example, the axially intermediate portion of the measured point P). Measure the contact temperature. The radiation thermometer 25 connects the light-receiving section provided at the tip to the large flange in the axial direction of the measured point P (in the illustrated example, the measured point P is It is made to oppose the end part on the axially inner surface 22a side of the portion 16a. Thereby, the radiation thermometer 25 measures the radiation temperature of the point to be measured P based on receiving the light emitted from the point to be measured P and passed through the grease G that covers the point to be measured P. . Each of the contact thermometer 24 and the radiation thermometer 25 is supported and fixed to a portion that does not rotate with respect to the inner ring 12a (for example, a nut 23, a part of a sealing device (not shown), etc.).

A diagnostic device 26 constituting the diagnostic system 3 is installed on the vehicle body side, and is connected to a contact thermometer 24 and a radiation thermometer 25 via a harness (not shown). As a result, the output signal of the contact thermometer 24 (signal representing the contact temperature of the point to be measured P) and the output signal of the radiation thermometer 25 (signal representing the radiation temperature of the point to be measured P) are transmitted through the harness for diagnosis. device 26.

The diagnostic device 26 detects a change in the spectral brightness of wavelength components in a predetermined range of the light passing through the grease G due to the temperature of the tapered roller bearing 6a on the outside in the vehicle width direction and the contamination of the grease G of the tapered roller bearing 6a. Taking advantage of the above, seizure of the tapered roller bearing 6a on the outer side in the vehicle width direction, specifically, the seizure of the large diameter side end surface 21a of each tapered roller 14a and the axially inner surface 22a of the large flange portion 16a is prevented. Equipped with a function to determine whether there are signs of seizure in the sliding contact area.

Specifically, the diagnostic device 26 determines whether there is a sign of burn-in based on the following principle.

FIG. 3 is a log-log graph (horizontal axis: wavelength, vertical axis: spectral brightness (light amount)) showing the spectrum of light (ultraviolet rays, visible light, infrared rays) emitted from a black body at each temperature. This relationship between the spectrum of light and temperature is derived from Planck's law. Light with a spectrum corresponding to the temperature is also emitted from the measurement point P existing on a part of the outer circumferential surface 20a of the large flange portion 16a, which is a black surface (black body).

However, the grease G covering the measurement point P contains oxidized wear particles generated at the contact portion between the surface of the tapered roller 14a and the other surface. Most of such oxidized wear powder is generated at the sliding contact portion between the large-diameter side end surface 21a of each tapered roller 14a and the axially inner surface 22a of the large collar portion 16a, and is mainly composed of α-Fe ₂ It consists of O ₃ (hematite, characteristic absorption bands: 470 cm ^-1 , 540 cm ^-1 ) and γ-Fe ₂ O ₃ (machematite, characteristic absorption bands: 448 cm ^-1 , 578 cm ^-1 ).

Such oxidized wear powder has far-infrared absorption characteristics (characteristic absorption band) with a wave number of around 500 cm ^-1 (wavelength of 20 μm). For this reason, when the content of oxidized wear particles in grease G increases, among the light emitted from the measurement point P and passing through grease G, components with wave numbers around 500 cm ^-1 (wavelength 20 μm), specific Specifically, at least the spectral brightness of components with wavelengths of 17 μm or more and 23 μm or less is reduced.

For example, at a temperature (approximately 500 K) at which seizure may occur at the sliding contact portion between the large-diameter side end surface 21a of each tapered roller 14a and the axially inner surface 22a of the large flange portion 16a, the wave number is 500 cm ^-1 A component near (wavelength: 20 μm) becomes a wavelength component longer than the peak wavelength, and the spectral brightness of that wavelength component decreases as shown by the broken line in FIG. 3. As a result, the decreasing slope of the spectral brightness increases from the peak wavelength toward the longer wavelength side, and the brightness distribution after the decrease, that is, the brightness distribution of the light received by the light receiving part of the radiation thermometer 25, becomes The brightness distribution approaches that at higher temperatures.

The radiation thermometer 25 measures the radiation temperature of the measurement point P from the frequency distribution of the received light and the spectral brightness for each frequency. When the luminance distribution approaches the luminance distribution of the measured point P, the radiation temperature of the measured point P measured by the radiation thermometer 25 becomes lower than the actual temperature of the measured point P (≒contact temperature of the measured point P measured by the contact thermometer 24). also becomes larger. As a result, a difference ΔTa (absolute value) occurs between the contact temperature of the measured point P measured by the contact thermometer 24 and the radiation temperature of the measured point P measured by the radiation thermometer 25. Become.

Additionally, as the content of oxidized wear particles in the grease G increases over time, the wave number of the light emitted from the measurement point P and passing through the grease G will be 500 cm ^-1 (wavelength The amount of decrease in the spectral brightness of components around 20 μm also increases. As a result, the radiation temperature of the measured point P measured by the radiation thermometer 25 shifts to a higher side than the actual temperature of the measured point P, and the difference ΔTa increases.

On the other hand, as the content of oxidized wear particles in the grease G increases over time, sliding contact between the large-diameter side end surfaces 21a of each tapered roller 14a and the axially inner surface 22a of the large collar portion 16a occurs. The lubricating condition of the parts deteriorates, and seizure is more likely to occur than when the grease G is new.

Therefore, with the structure of this example, it is possible to determine whether there is a sign of burn-in based on evaluating the difference ΔTa.

In this example, as shown in FIG. The difference (difference △Ta) from the radiation temperature of the measured point P measured by Total 25 is confirmed, and it is determined that this difference is out of the predetermined range (exceeds the predetermined specified value Ya (△Ta> Ya)), it is determined that there is a sign of burn-in. In this example, the value Xa of the difference △Ta when burn-in occurs is investigated in advance by conducting an experiment, and a value slightly smaller than the investigated value Xa (for example, (0.8 to 0.9 )Xa) is defined as the specified value Ya.

Further, if the diagnostic device 26 determines that there is a sign of burn-in, the diagnostic device 26 displays the result of the determination in an appropriate manner, such as visually displaying the result on a display or outputting it audibly through a speaker. Notify the driver etc. That is, it notifies the driver etc. that maintenance of the rotation support device 2 (replacement of grease G, parts, etc.) is required.

In the rotary support device 1 with a diagnostic system of this example as described above, the presence or absence of a sign of seizing in the tapered roller bearing 6a on the outside in the vehicle width direction is determined not only by the temperature but also by the state of occurrence of oxidized wear particles (lubrication state). It can be determined by Therefore, compared to determining whether there is a sign of burn-in by considering only the temperature, it is possible to determine the presence or absence of a sign of burn-in more accurately.In other words, it is possible to detect the sign of burn-in more accurately. be able to.

In addition, when implementing the present invention, it is preferable that the color of the measurement point P whose radiation temperature is measured by the radiation thermometer 25 be black, which has the highest emissivity, as in this example. However, when implementing the present invention, the color of the measurement point P whose temperature is measured by the radiation thermometer 25 is not necessarily black as long as the color has an emissivity that allows appropriate determination of the presence or absence of signs of burn-in. It doesn't have to be.

Further, when carrying out the present invention, the configuration for determining whether or not there is a sign of seizure in the first example of the embodiment is replaced with the tapered roller bearing 6a on the outside in the vehicle width direction (or It can also be applied to the tapered roller bearing 6b on the inner side in the vehicle width direction (along with the outer tapered roller bearing 6a).

[Second example of embodiment]
A second example of the embodiment will be described using FIGS. 5 to 9.
In the structure of this example as well, the diagnostic device 26 (see FIG. 1) constituting the diagnostic system 3a detects a certain amount of light that passes through the grease G due to contamination of the grease G of the tapered roller bearing 6a on the outside in the vehicle width direction. By utilizing the change in the spectral brightness of the wavelength components within the range, seizure of the tapered roller bearing 6a on the outside in the vehicle width direction, specifically, the seizure of the large diameter side end surface 21a and the large flange portion 16a of each tapered roller 14a is detected. It has a function of determining whether or not there is a sign of seizure in the sliding contact portion with the axial inner surface 22a. However, in this example, the configuration for realizing this function is different from the first example of the embodiment.

In the structure of this example, the diagnostic system 3a includes a contact thermometer 24 similar to the structure of the first example of the embodiment. Then, the contact thermometer 24 brings its detection portion into contact with the measuring point P (in the illustrated example, the axially intermediate portion of the measuring point P) located at the lower end of the outer peripheral surface 20c of the large flange portion 16a. By doing so, the temperature (contact temperature) of the measurement point P is measured. In this example, since the only thermometer that measures the temperature of the outer circumferential surface 20c (measurement point P) of the large flange 16a is the contact thermometer 24, the color of the outer circumferential surface 20c of the large flange 16a is determined by the temperature. does not affect the measurement results. Therefore, in this example, the color of the outer circumferential surface 20c of the large flange portion 16a is not black, but the outer circumferential surface 20c of the large flange portion 16a is made of a shiny surface after machining.

In addition, when implementing this invention, a radiation thermometer can also be used as a thermometer for measuring the temperature of the to-be-measured location P instead of the contact thermometer 24. When using a radiation thermometer, it is preferable that the color of the measurement point P be black, which has the highest emissivity. In addition, when using a radiation thermometer, take into account the error (ΔTa) caused by the absorption of far infrared rays by oxidized wear powder, and correct the indicated value of the radiation thermometer, or correct the temperature threshold for determining signs of seizure. good.

Moreover, in comparison with the structure of the first example of the embodiment, the diagnostic system 3a includes a light emitter 27 and a light receiver 28 instead of the radiation thermometer 25 (see FIG. 2). As shown in FIGS. 6 and 7, the light emitter 27 and the light receiver 28 are located at a position facing the lower end of the outer circumferential surface 20c of the large flange 16a of the inner ring 12a. Among the measurement points P, the grease G (shown only in FIG. 7) that covers the axially inner surface 22a side end of the large flange 16a in the axial direction is placed facing each other (separated in the circumferential direction). The inner ring 12a is supported and fixed to a portion that does not rotate with respect to the inner ring 12a (for example, the nut 23, a part of a sealing device (not shown), etc.). In this state, the light emitted from the light emitter 27 and passed through the grease G covering the measurement point P is received by the light receiver 28.

Therefore, in the structure of this example, as the content of oxidized wear particles in the grease G (degree of contamination of the grease) increases with the passage of usage time, the light emitted from the measurement point P and passing through the grease G increases. Of these, the absorption rate of components with a wave number of around 500 cm ^-1 (wavelength of 20 μm) increases. Then, of the light received by the light receiver 28, the spectral brightness of a component with a wave number around 500 cm ^-1 (wavelength 20 μm), specifically, the spectral brightness of a component with a wavelength of at least 17 μm or more and 23 μm or less decreases.

In this example, as shown in FIG. (spectral luminance of a component near 500 cm ⁻¹ (wavelength: 20 μm)), it is possible to determine a sign of burn-in (for example, based on the relationship in the image diagram shown in FIG. 9). Note that the threshold value (equation) based on two parameters, the temperature of the measured location and the degree of contamination of the grease, is determined to be an appropriate value by conducting experiments in advance.

In the case of the structure of this example as described above, the presence or absence of a sign of seizing of the tapered roller bearing 6a on the outside in the vehicle width direction is determined not only by the temperature but also by taking into consideration the state of occurrence of oxidized wear particles (lubrication state). be able to. Therefore, compared to determining whether there is a sign of burn-in by considering only the temperature, it is possible to determine the presence or absence of a sign of burn-in more accurately.In other words, it is possible to detect the sign of burn-in more accurately. be able to.

Note that when carrying out the present invention, the configuration for determining whether or not there is a sign of seizure in the second example of the embodiment is replaced with the tapered roller bearing 6a on the outside in the vehicle width direction (or It can also be applied to the tapered roller bearing 6b on the inner side in the vehicle width direction (along with the outer tapered roller bearing 6a).
Other configurations and effects are the same as in the first example of the embodiment.

The present invention can be implemented by appropriately combining the configurations of the respective embodiments described above to the extent that no contradiction occurs.

The present invention is applicable not only to large vehicles such as trucks and buses, but also to rotational support devices incorporated in various mechanical devices such as medium-sized vehicles, small vehicles, railway vehicles, windmills, rolling mills, machine tools, construction machinery, and agricultural machinery. can do.
Note that the rotation support device only needs to be configured to include a rolling bearing, and may be configured to include only a rolling bearing. Furthermore, the rolling bearing is not limited to a tapered roller bearing, but may be other types of rolling bearings such as a ball bearing or a cylindrical roller bearing. Further, the rolling bearing is not limited to a single row rolling bearing, but may be a double row rolling bearing. Furthermore, the rolling bearing is not limited to a radial rolling bearing, but may be a thrust rolling bearing.
Furthermore, when carrying out the present invention, the part to be measured may be any part of the member whose temperature rises and is covered with grease as the rolling bearing operates, and is not limited to part of the inner ring, for example. , a part of the outer ring, or a part of the spacer (for example, the outer peripheral surface of the inner ring spacer 108 shown in FIG. 10).

1 Rotation support device with diagnostic system 2 Rotation support device 3 Diagnosis system 4 Axle 5 Hub 6a, 6b Tapered roller bearing 7a, 7b Fitting surface portion 8 Step surface 9a, 9b Fitting surface portion 10a, 10b Step surface 11 Flange portion 12a, 12b Inner ring 13a, 13b Outer ring 14a, 14b Tapered roller 15a, 15b Inner ring raceway 16a, 16b Large flange 17a, 17b Small flange 18a, 18b Outer ring raceway 19a, 19b Cage 20a, 20b, 20c Outer surface 21a, 21b Large diameter side End surfaces 22a, 22b Axial inner surface 23 Nut 24 Contact thermometer
25 Radiation thermometer 26 Diagnosis device 27 Light emitter 28 Light receiver 100 Rotating support device with thermometer 101 Axle 102 Housing 103 Double row tapered roller bearing 104 Radiation thermometer 105 Outer ring 106 Inner ring 107 Tapered roller 108 Inner ring spacer 109 Outer ring raceway 110 Inner ring Raceway 111 Large collar 112 Cage 113 Large diameter end surface 114 Axial inner surface

Claims (4)

a pair of bearing rings;
a plurality of rolling elements arranged between the pair of bearing rings;
Grease that lubricates the contact portion between the surface of each of the plurality of rolling elements and the other surface;
A rolling bearing diagnostic system for diagnosing the condition of a rolling bearing, comprising:
Determining whether there is a sign of seizure by utilizing the temperature of the rolling bearing and the fact that the spectral brightness of a wavelength component in a predetermined range of light passing through the grease changes due to contamination of the grease. It has the function of
a detection unit, the detection unit is brought into contact with a measurement point of a member whose temperature rises as the rolling bearing operates and is covered with the grease, and the contact temperature of the measurement point is measured; A contact thermometer,
a radiation thermometer that has a light receiving section, and measures the radiation temperature of the measured point by arranging the light receiving section to face the measured point via the grease;
a diagnostic device that determines whether there is a sign of seizure in the rolling bearing based on the difference between the contact temperature and the radiation temperature;
Equipped with
Diagnostic system for rolling bearings. The rolling bearing has an outer ring having a conical concave outer ring raceway on the inner peripheral surface, a conical convex inner ring raceway on the outer peripheral surface, and a radial direction from a portion adjacent to the large diameter side of the inner ring raceway in the axial direction. an inner ring having a large flange projecting outward; and a plurality of rings arranged between the outer ring raceway and the inner ring raceway, each having a large diameter side end face facing an axially inner surface of the large flange part. A tapered roller bearing comprising tapered rollers and grease for lubricating a contact portion between the surface of each of the plurality of tapered rollers and a mating surface,
The point to be measured is the outer peripheral surface of the large flange portion,
The rolling bearing diagnostic system according to claim 1 . It has a function of determining the presence or absence of a sign of burn-in by utilizing changes in the spectral brightness of components with wavelengths of 17 μm or more and 23 μm or less of the light that has passed through the grease.
The rolling bearing diagnostic system according to claim 1 or 2 . A rotation support device including a rolling bearing, and a rolling bearing diagnosis system for diagnosing the condition of the rolling bearing,
The rolling bearing includes a pair of bearing rings, a plurality of rolling elements arranged between the pair of bearing rings, and a contact portion between a surface of each of the plurality of rolling elements and a mating surface. equipped with lubricating grease;
The rolling bearing diagnostic system is a rolling bearing diagnostic system according to any one of claims 1 to 3 .
Rotating support device with diagnostic system.

Images