WO2012098980A1

WO2012098980A1 - Bearing provided with seal equipped with sensor

Info

Publication number: WO2012098980A1
Application number: PCT/JP2012/050455
Authority: WO
Inventors: 近藤博光; 梅本武彦
Original assignee: Ntn株式会社
Priority date: 2011-01-20
Filing date: 2012-01-12
Publication date: 2012-07-26
Also published as: JP2012149716A

Abstract

Provided is a bearing provided with a seal which is equipped with a sensor, the bearing being configured in such a manner that status information relating to the bearing can be detected, the bearing can be applied to any place of installation, can be applied to bearings of existing designs, and is interchangeable with existing bearings. This bearing (1) provided with a seal which is equipped with a sensor comprises: an inner ring (2); an outer ring (3); rolling bodies (4) disposed between the inner and outer rings (2, 3); and the seal (6) which seals the bearing space between the inner and outer rings (2, 3). The seal (6) is provided with: one or more sensors (12, 13) for detecting the status information relating to the bearing; an information handling means (14) for managing the information detected by the sensors (12, 13); and an electric power source (15) having an electric power generating function for driving the information handling means (14) and the sensors (12, 13).

Description

Sealed bearing with sensor

Related applications

This application claims the priority of Japanese Patent Application No. 2011-009352 filed on January 20, 2011, and is incorporated herein by reference in its entirety as a part of this application.

This invention relates to a sensor-equipped seal bearing in which a sensor for detecting bearing state information such as temperature and vibration is provided in a seal that seals a bearing space between inner and outer rings of the bearing.

As a conventional example of a sensor-equipped seal bearing in which a sensor is provided on the seal, an iron powder content detection sensor is attached to the side surface of the bearing ring, and the stylus is passed through the seal (for example, a patent) Reference 1). Moreover, although it is unknown whether it is a bearing with a seal, the bearing information communication system which transmits the bearing state information which the sensor detected to the exterior is also known (for example, patent document 2).

JP 2003-269470 A JP 2003-194047 A

In the bearing equipped with a sensor-equipped seal disclosed in Patent Document 1, the sensor is disposed on the side surface of the raceway so as to protrude outside the bearing dimensions, and it is necessary to secure a sensor space when installing the bearing. . That is, even if an attempt is made to place the sensor-equipped seal bearing in the existing bearing space in place of the existing bearing, it cannot be replaced because the sensor space cannot be secured. In addition, since the power source of the sensor is supplied from the outside, applicable installation places are limited.

The bearing information communication system disclosed in Patent Document 2 is a technique for transmitting bearing information detected by a sensor in a sensor-equipped bearing, and does not disclose any part of the bearing where the sensor is arranged.

The object of the present invention is to be able to detect bearing information, and can be applied to any installation location, and can also be applied to a bearing of an existing design, and a sensor-equipped seal having compatibility with components and installation with an existing bearing. Provided bearings.

A sensor-equipped seal bearing according to the present invention is a bearing including an inner ring and an outer ring, a rolling element interposed between the inner and outer rings, and a seal that seals a bearing space between the inner and outer rings. One or more sensors for detecting bearing state information, information handling means for handling the information detected by the sensors, and a power source having a power generation function capable of driving the information handling means and the sensor are provided. is there.

According to this configuration, since the sensor, the information handling means, and the power source are provided on the bearing seal, detection by the sensor and handling of the detected information by the information handling means are possible without using an external power source. Therefore, it can be applied at any installation location without being affected by the infrastructure. Since sensors, information handling means, and power supply are provided on the seal, it is not necessary to process the bearing ring to install these sensors, information handling means, and power supply, and can be applied to existing design bearings. Compatibility with bearings is also possible. In addition, even if the sensor, information handling means, power source, etc. break down, the entire seal can be replaced, and can be easily replaced.

The sensor, information handling means, and power supply are provided on the seal, so that they can be stored in the bearing space without protruding from the bearing ring, unlike the case where it is provided on the side of the bearing ring, or when protruding from the bearing space. Even so, the seal is in a position to seal the bearing space, and unlike the race, in most cases, the adjacent portion is a space. Therefore, it is possible to install compatible with existing bearings without causing the problem of interference caused by protrusions of these sensors and power supplies, etc., while having sensors, information handling means, and power supplies.

In particular, when the entire seal including the sensor, the information handling means, and the power source is accommodated in the bearing space, it is compatible with existing bearings without causing any interference problems due to protrusion of the sensor, power source, etc. Can be installed.

In this invention, the information handling means may be a transmitter that transmits information detected by the sensor to the outside. In the case of this configuration, since the information detected by the sensor can be transmitted to the outside by the transmitter, the bearings can be managed remotely.

In the present invention, the information handling means may be a recording device that records information detected by the sensor. In this configuration, since the information detected by the sensor can be recorded by the recording device, it is not necessary to manage the information by sticking to the installation location of the bearing, and the bearing state can be easily managed.

In the present invention, the information handling means may include a recording device for recording information detected by the sensor and a transmitter for transmitting information detected by the sensor to the outside. In the case of this configuration, the information detected by the sensor can be recorded by the recording device and can be transmitted to the outside by the transmitter, so that the management of the bearing state is further facilitated.

In this invention, the transmitter may be a wireless transmitter. Since the wireless transmitter does not require wiring, it is possible to obtain a high degree of freedom in the installation location of the bearing with the sensor-equipped seal in combination with a configuration in which a power source is provided on the seal and an external power source is unnecessary.

In this invention, the bearing state information detected by the sensor may be one or both of vibration and temperature of the bearing. Since a bearing abnormality can be generally determined by vibration or temperature, the bearing abnormality can be monitored by detecting the vibration or temperature.

In this invention, the power source may be a Seebeck power generation element. The Seebeck power generation element is an element that generates power based on a temperature difference, and can generate power by effectively using the temperature difference between the inside and outside of the seal.

In the present invention, the power source may be a vibration power generation element. In this case, the vibration power generation element may be an electret element. Since the bearing seal generates vibration due to rotation, power can be generated by effectively using the vibration.

In this invention, the seal may further be provided with power storage means for storing electricity generated by the power source. In this case, the power storage means may be a capacitor or a storage battery such as a lithium ion battery. When the power storage means is added in this way, even when the power source cannot generate power, the power storage means can normally collect, record, and transmit bearing state information.

In this invention, the seal is preferably removable from the bearing. If the seal can be removed from the bearing, the sensor, the information handling means, and the power source provided on the seal can be easily replaced together with the seal, so that failure of these components can be easily handled.

Any combination of at least two configurations disclosed in the claims and / or the specification and / or drawings is included in the present invention. In particular, any combination of two or more of each claim in the claims is included in the present invention.

The present invention will be more clearly understood from the following description of preferred embodiments with reference to the accompanying drawings. However, the embodiments and drawings are for illustration and description only and should not be used to define the scope of the present invention. The scope of the invention is defined by the appended claims. In the accompanying drawings, the same reference numerals in a plurality of drawings indicate the same or corresponding parts.
It is a longitudinal section of a bearing with a sensor equipment seal concerning a 1st embodiment of this invention. It is a block diagram of the sensor unit provided in the seal of the bearing with the sensor equipment seal. It is a longitudinal cross-sectional view of a sensor-equipped seal bearing used in a temperature measurement test for confirming that a Seebeck element can be applied as a power source that is a component of the sensor unit. (A) is a partial perspective view showing an arrangement example of the temperature sensitive element on the seal surface of the bearing in the same temperature measurement test, (B) is a sectional view of the same part, (C) is an arrangement of the temperature sensitive element on the back surface of the seal. It is a fragmentary perspective view which shows an example. It is a longitudinal cross-sectional view of the spindle apparatus in which the bearing with a seal for the test was incorporated. It is a graph which shows the result of the test. (A) And (B) is an operation principle figure of a vibration power generation element applicable as a power supply which is a component of the sensor unit. It is a longitudinal cross-sectional view of the bearing with a sensor equipment seal concerning 2nd Embodiment of this invention. It is a block diagram of the sensor unit provided in the seal of the bearing with the sensor equipment seal. It is a longitudinal cross-sectional view of the bearing with a sensor equipment seal concerning 3rd Embodiment of this invention. It is a block diagram of the sensor unit provided in the seal of the bearing with the sensor equipment seal.

A first embodiment of the present invention will be described with reference to FIGS. 1 to 7A and 7B. The sensor-equipped sealed bearing 1 according to this embodiment is a rolling bearing used for, for example, an automobile transmission, and a plurality of rolling elements 4 are interposed between

raceway surfaces

2a and 3a of an inner ring 2 and an outer ring 3, A cage 5 for holding the rolling element 4 is provided, and both ends of an annular bearing space formed between the inner and

outer rings

2 and 3 are sealed with seals 6 respectively. Grease is initially sealed in the bearing. This rolling bearing is a deep groove ball bearing in which the rolling elements 4 are balls, and is an inner ring rotating type in which the inner ring 2 is a rotating ring and the outer ring 3 is a fixed ring.

The seal 6 includes an annular cored bar 7 and an elastic member 8 such as rubber that is integrally fixed to the cored bar 7. The seal mounting groove 9 is formed on the inner peripheral surface of the outer ring 3 that is a fixed ring. The outer peripheral portion is fixed to the fitted state. In the inner ring 2 that is a rotating wheel, a seal groove 10 formed of a circumferential groove is formed at a position corresponding to the inner peripheral portion of each seal 6. At the inner peripheral side end of the elastic member 8 in the seal 6,

seal lip portions

8 a and 8 b that are divided into two are formed. One seal lip portion 8 a is in axial contact with the inner wall surface of the seal groove 10 of the inner ring 2. The other seal lip 8b is in radial contact with a part of the outer diameter surface extending from the outer wall surface of the seal groove 10 to the outside of the bearing. The entire seal 6 is formed by vulcanizing and molding a rubber material as the elastic member 8 on the core metal 7.

Of the left and right seals 6, one of the seals 6 includes two

sensors

12 and 13, a transmitter 14 that is information handling means for handling bearing state information detected by the

sensors

12 and 13, and a power source 15. The sensor unit 11 is integrally provided. FIG. 2 shows a block diagram of the sensor unit 11. Here, one sensor 12 detects bearing temperature, which is one of bearing state information, and another sensor 13 detects bearing vibration, which is other state information of the bearing. In this case, the two

sensors

12 and 13 are provided. However, only the sensor 12 for detecting the bearing temperature or the sensor 13 for detecting the bearing vibration may be provided. In addition to the

sensors

12 and 13, For example, another sensor for detecting the amount of iron powder containing grease may be provided.

The transmitter 14 is a wireless transmitter for transmitting the bearing state information detected by the

sensors

12 and 13 to the outside. The transmitter 14 is wirelessly connected to an external information processing device (not shown) remote from the bearing installation portion. Send status information. The power source 15 has a power generation function, and supplies the

sensors

12 and 13 and the transmitter 14 with power necessary for driving them. As the power supply 15 having the power generation function, a Seebeck element that is a thermoelectric generation element or an electret element that is a vibration power generation element can be applied.

FIGS. 3 to 6 describe a temperature measurement test performed to confirm that the Seebeck element can be applied as the power source 15 having a power generation function. FIG. 3 shows a longitudinal sectional view of the sealed bearing 21 used in this test. This test bearing 21 with seal is different from the sensor-equipped seal bearing 1 of FIG. 1 in that the sensor unit 11 is not provided on the seal 6, and other configurations are the sensor-equipped seal bearing 1 of FIG. 1. Is the same.

As shown in FIG. 4A, a temperature sensing element 22 is arranged on the surface of one seal 6 in the bearing 21 with a seal for testing, and is fixed by a resin 20. The temperature is measured. As shown in FIG. 4B, another temperature sensing element 23 is disposed on the back surface of the same seal 6 and fixed with the resin 20, and the temperature sensing element 23 measures the back surface temperature of the seal 6. The

temperature sensing elements

22 and 23 on the front and back sides are fixed to the same place in a planar manner, and the same places on the front and back of the seal 6 are measured. The temperature

sensitive elements

22 and 23 are connected to the

cords

42 and 43, respectively, and the cord 43 of the temperature sensitive element 23 on the back side is through a hole 44 provided in the seal 6 as shown in FIG. It is pulled out to the front side.

FIG. 5 shows a longitudinal sectional view of a spindle apparatus which is a testing machine in which the bearing 21 with a test seal of FIG. 3 is incorporated. The spindle device 24 is applied to a machine tool, and a tool 40 or a workpiece chuck is attached to the front side (machining side) end of the main shaft 25. The main shaft 25 is supported by two bearings 21 with test seals separated in the axial direction. The inner ring 2 of each sealed bearing 21 is fitted to the outer diameter surface of the main shaft 25, and the outer ring 3 is fitted to the inner diameter surface of the bearing housing 26.

As for the sealed bearing 21 on the front side of the main shaft, the inner ring 2 is fixed in the bearing box 26 by an inner ring positioning spacer 27 and the outer ring 3 is fixed by a pressing lid 28A. As for the bearing 21 with the seal on the rear side of the main shaft, the inner ring 2 is fixed in the bearing box 26 by the step surface 25a of the main shaft 25 through the inner ring positioning spacer 29, and the outer ring 3 by the pressing lid 28B. The bearing box 26 has a double structure of an inner peripheral bearing box 26A and an outer peripheral bearing box 26B, and a cooling groove 30 is formed between the inner and outer bearing boxes 26A, 26B. An inner ring spacer 31 is interposed between the adjacent

inner rings

2 and 2 of the bearings with seals 21, and an outer ring spacer 32 is interposed between the adjacent

outer rings

3 and 3. A bearing fixing nut 33 that presses against the inner ring positioning spacer 27 and fixes the sealed bearing 21 is screwed to the front end portion of the main shaft 25. The spindle device 24 is driven, and the temperatures of the front and back surfaces of the seal 6 in the bearing 21 with seal at that time are measured.

Table 1 shows the results of the temperature measurement test, where CH1 indicates seal surface temperature data and CH2 indicates seal back surface temperature data. 6 shows the rotational speed of the main shaft 25 (graph (3) in the figure), the measured seal surface temperature (graph (1) in the figure), and the seal back surface temperature ((2) in the figure). And the reference temperature (graph (4) in the figure).

In addition, the type of the sealed bearing 21 used in this temperature measurement test and the test conditions are as follows.
1. Test bearing # 20 (100 inside diameter)
2. Test conditions ・ Rotational speed 3000 to 15000 min ⁻¹ (dn = 300,000 to 1,500,000)
・ Encapsulated grease: Grease made by NOK Crubber Enclosed amount in the bearing = 7 g (25% of space volume)
Application amount to bearing end face = 1g
・ Cylinder cooling: Yes, room temperature tuning 10 l / min
・ Test posture: Horizontal axis

From the results of this temperature measurement test, as shown in FIG. 6, it is confirmed that the back surface of the seal 6 (graph (2) in the figure) is higher in temperature than the front surface (graph (1) in the figure). It was done. In the vicinity of the rolling element 4 in the bearing 21 with the seal, it is considered that the temperature increases due to the influence of heat generated by the rotation. In this test, a maximum temperature difference of 7.5 ° C. (48.5 ° C.-41.0 ° C.) between the seal surface and the seal back surface was obtained at 15000 min ⁻¹ . When a temperature difference of 5 ° C. or more is obtained, a Seebeck element can be generally used as the power source 15 having the above-described power generation function.

7A and 7B show the operation principle of an electret element that is one of the vibration power generation elements applicable as the power supply 15 having a power generation function. The electret element 17 has an electret electrode substrate 18 and a metal electrode substrate 19 that are arranged to face each other as shown in FIG. 7A, which shows a stationary state, and the electret electrode substrate 18 and the metal electrode substrate 19 are stationary. When 19 is opposed, charge is induced. When the positions are shifted from each other due to movement due to vibration as shown in FIG. Thereby, power generation is performed.

As described above, according to the sensor-equipped seal bearing 1, the seal 6 includes the

sensors

12 and 13, the transmitter 14 serving as information handling means, and the power source 15 that drives the

sensors

12, 13 and the transmitter 14. Since it is provided, detection by the sensor 6 and transmission of the detected information can be performed without using an external power source. Therefore, it can be applied at any installation location without being affected by the infrastructure. Since the sensor 6, the transmitter 14, and the power source 15 are provided on the seal 6, it is not necessary to process the outer ring 3, the inner ring 2 and the like for the installation of the

sensors

12, 13 and the transmitter 14 and the power source 15. It can also be applied to bearings of this design and can be interchanged with existing bearings. In addition, even if the sensor 6, the transmitter 14, the power supply 15, etc. break down, the seal unit 11 can be replaced and can be replaced easily.

Since the

sensors

12, 13, the transmitter 14, and the power source 15 are provided on the seal 6, unlike the case where the

sensors

12 and 13 are provided on the side surface of the race, etc., they can be accommodated in the bearing space without protruding from the race. Even when protruding from the space, the seal 6 is in a position to seal the bearing space, and unlike the races, in most cases, the adjacent portion is a space. Therefore, while having the

sensors

12, 13, the transmitter 14, and the power supply 15, the installation compatible with the existing bearing is possible without causing the problem of interference due to the protrusion of the

sensors

12, 13, the power supply 15 and the like. .

In particular, when the entire seal unit 11 including the sensor 6, the transmitter 14, and the power source 15 is accommodated in the bearing space as in the illustrated example, interference due to protrusions of the

sensors

12, 13, the power source 15 and the like is caused. Installation compatible with existing bearings is possible without causing any problems.

In the first embodiment, since the seal 6 can be removed from the outer ring 3 that is a fixed ring, together with the seal 6,

sensors

12 and 13 provided on the seal 6, a transmitter 14 that is information handling means, In addition, the power source 15 can be easily replaced, and the failure of these parts can be easily handled.

8 and 9 show a second embodiment of the present invention. The sensor-equipped seal bearing according to the second embodiment is one of the components of the sensor unit 11 provided in the seal 6 in the first embodiment shown in FIGS. 1 to 7A and 7B. The machine 14 is replaced with a recording device 16 which is another information handling means. The recording device 16 in this case records the bearing state information detected by the

sensors

12 and 13. For example, an IC tag can be used as the recording device 16. Other configurations are the same as those of the first embodiment shown in FIGS. 1 to 7A and 7B.

In the case of this second embodiment, since the information detected by the

sensors

12, 13 can be recorded by the recording device 16, it is not necessary to stick to the installation location of the bearing 1 with the sensor-equipped seal, and management of the bearing is easy. Can be done. Other functions and effects are the same as those of the first embodiment shown in FIGS. 1 to 7A and 7B.

10 and 11 show a third embodiment of the present invention. The sensor-equipped seal bearing according to the third embodiment is the same as that of the sensor unit 11 provided in the seal 6 in the first embodiment shown in FIGS. 1 to 7A and 7B. In addition to the transmitter 14, a recording device 16 for recording the information is provided as information handling means for managing the information detected by 13. For example, an IC tag can be used as the recording device 16 as in the case of the second embodiment shown in FIGS. Other configurations are the same as those of the first embodiment shown in FIGS. 1 to 7A and 7B.

In the case of the third embodiment, since the information detected by the

sensors

12 and 13 can be recorded by the recording device 16 and can be transmitted to the outside by the transmitter 14, the bearing management is further facilitated. Other functions and effects are the same as those of the first embodiment shown in FIGS. 1 to 7A and 7B.

In each of the embodiments described above, a power storage means for storing electricity generated by the power source 15 may be further provided as a component of the sensor unit 11 provided in the seal 6. When the power storage means is added in this way, even when the power source 15 cannot generate power, the power storage means can normally collect, record, and transmit bearing state information. In this case, the power storage means may be a capacitor or a lithium ion battery.

As described above, the preferred embodiments have been described with reference to the drawings. However, those skilled in the art will readily assume various changes and modifications within the obvious scope by looking at the present specification. Accordingly, such changes and modifications are to be construed as within the scope of the invention as defined by the appended claims.

DESCRIPTION OF SYMBOLS 1 ... Sensor-equipped seal bearing 2 ... Inner ring 3 ... Outer ring 4 ... Rolling element 6 ... Seal 9 ... Seal mounting groove 11 ...

Sensor unit

12, 13 ... Sensor 14 ... Transmitter (information handling means)
15 ... Power supply 16 ... Recording device 17 ... Electret element

Claims

A bearing comprising an inner ring and an outer ring, a rolling element interposed between the inner and outer rings, and a seal for sealing a bearing space between the inner and outer rings,
The seal is provided with one or more sensors for detecting bearing state information, information handling means for handling information detected by the sensors, and a power source having a power generation function capable of driving the information handling means and the sensor. Bearing with sensor and seal.
The bearing with a seal according to claim 1, wherein the entire seal including the sensor, the information handling means, and the power source is accommodated in the bearing space.
The sensor-equipped seal bearing according to claim 1, wherein the information handling means is a transmitter for transmitting information detected by the sensor to the outside.
The sensor-equipped seal bearing according to claim 3, wherein the transmitter is a wireless transmitter.
2. The bearing with a sensor-equipped seal according to claim 1, wherein the information handling means is a recording device that records information detected by the sensor.
The sensor-equipped seal bearing according to claim 1, wherein the information handling unit includes a recording device that records information detected by the sensor and a transmitter that transmits information detected by the sensor to the outside.
The sensor-equipped seal bearing according to claim 6, wherein the transmitter is a wireless transmitter.
The bearing with a sensor-equipped seal according to claim 1, wherein the state information of the bearing detected by the sensor is one or both of vibration and temperature of the bearing.
The sensor-equipped seal bearing according to claim 1, wherein the power source is a Seebeck power generation element.
The sensor-equipped seal bearing according to claim 1, wherein the power source is a vibration power generation element.
The sensor-equipped seal bearing according to claim 10, wherein the vibration power generation element is an electret element.
The bearing with a sensor-equipped seal according to claim 1, wherein the seal is further provided with power storage means for storing electricity generated by the power source.
The sensor-equipped seal bearing according to claim 12, wherein the power storage means is a capacitor.
The sensor-equipped seal bearing according to claim 12, wherein the power storage means is a lithium ion battery.
The sensor-equipped seal bearing according to claim 1, wherein the seal is removable from the bearing.