JP4066145B2 - Rolling bearing with sensor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sensor-equipped rolling bearing provided with a sensor for detecting vibration and temperature, and is particularly suitable for detecting an abnormality of a bearing used in an industrial machine.
[0002]
[Prior art]
Conventionally, as a rolling bearing with a sensor for detecting rotational speed, vibration and temperature, there are those disclosed in, for example, Japanese Patent No. 2618795 and Japanese Translation of PCT Application No. 2001-50097.
[0003]
Japanese Patent No. 2618795 discloses a bearing in which a speed sensor and a temperature sensor are arranged outside the end face of the bearing while changing the phase on the circumference.
Japanese Patent Application Publication No. 2001-5000597 discloses a bearing to which a sensor module integrated with a speed / vibration / temperature sensor is attached.
[0004]
[Problems to be solved by the invention]
However, in the above conventional example, the sensor for detecting vibration and temperature is fixed to the bearing via a fixing resin or the like, so that it is not always excellent from the viewpoint of responsiveness of signal detection. I could not say.
The present invention has been made in view of the above circumstances, and an object thereof is to provide a sensor-equipped rolling bearing capable of detecting changes in vibration, temperature, and the like of the bearing with excellent responsiveness.
[0005]
[Means for Solving the Problems]
The object of the present invention is achieved by the following configurations.
(1) A rolling bearing provided with an inner ring, an outer ring, and a rolling element interposed between the inner and outer rings and used in a state where a contact angle is generated by applying a preload or an axial load, and the inner and outer rings of the rolling bearing A sensor-equipped rolling bearing comprising a sensor unit attached to an axial end of a stationary wheel,
The sensor unit has a flat surface portion extending in the axial direction substantially flush with the outer diameter surface of the outer ring, and a vertical portion extending radially inward from the front end of the flat surface portion, and is formed in an L-shaped cross section. A metal plate is integrally provided on the inner peripheral side of the flat portion of the metal plate and on the inner side in the axial direction of the vertical portion. The metal plate is opposed to the axial end surface of the stationary wheel, and a sensor is provided at the opposite portion. A holding block made of synthetic resin provided with a housing recess;
A vibration sensor and / or a temperature sensor held in the receiving recess of the holding block,
With the sensor, the metal plate or the holding block is attached to the axial end of the stationary wheel in a state where the sensor held in the housing recess is in close contact with the axial end surface of the stationary wheel. Rolling bearing.
(2) The sensor-equipped rolling bearing according to (1), wherein a substrate is disposed in the holding block, and the output line of the sensor is connected to the substrate, and the output line is led out from the substrate.
(3) The vibration sensor is a rolling bearing with a sensor according to (1) or (2), which is capable of detecting vibration in an axial direction of the rolling bearing.
(4) The sensor-equipped rolling bearing according to any one of (1) to (3), in which the vibration sensor, the temperature sensor, and other sensors are arranged so as to be shifted in the circumferential direction.
(5) A detected member is provided on the rotating wheel side of the inner and outer rings, and a rotational speed sensor for detecting the rotational speed of the detected member is provided on the stationary wheel side (1) to (4). A rolling bearing with a sensor according to any one of the above.
[0006]
According to the rolling bearing with a sensor having the above-described configuration, the metal plate or the holding member is held in a state where one or both of the vibration sensor and the temperature sensor held in the storage recess of the holding block of the sensor unit are in close contact with the axial end surface of the stationary wheel. since the block is attached to the axial end portion of the stationary ring, the detection sensitivity of the vibration and temperature by the sensors is improved. In particular, by directly contacting the vibration sensor held in the holding recess of the holding block without interposing another member to the axial end surface of the stationary wheel, the response is excellent and abnormal vibration can be detected early. . In addition, by directly contacting the temperature sensor held in the holding recess of the holding block to the axial end surface of the stationary wheel, the bearing temperature can be quickly transmitted to the temperature sensor, and the bearing temperature rise can be detected early. be able to.
In addition, since the vibration sensor held in the housing recess of the holding block of the sensor unit is in close contact with the axial end surface of the stationary wheel, the sensor can be easily attached. Further, it is possible to cope with a small bearing having a narrow radial gap (bearing space) between the inner and outer rings. The vibration sensor, temperature sensor, and other sensors are preferably displaced in the circumferential direction and are in close contact with the axial end surface of the stationary ring, so that even smaller bearings can be accommodated.
[0007]
Most of the bearing damage is seizure due to flaking of the raceway surface or lack of lubricant. The flaking of the raceway surface may occur on the stationary wheel or the rotating wheel alone or on both of them. When the rotating wheel is broken, the vibration of the bearing accompanying the peeling appears symmetrically with respect to the axis. On the other hand, as shown in FIG. 4, when the stationary ring (here, the outer ring) is peeled off, the vibration of the bearing accompanying the peeling is a direction connecting the center of the rolling element and the place where the peeling occurs. It becomes the maximum in. FIG. 4 assumes a state in which a preload or an axial load is applied to the bearing and a contact angle θ is generated. Assuming that the vibration in the direction connecting the center of the rolling element and the portion where the peeling occurs is V, the vibration of Va = Vsin θ appears in the axial direction. By detecting this axial vibration Va with a vibration sensor, it is possible to detect with high sensitivity the abnormal vibration associated with the flaking of the raceway surface of the stationary wheel.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a rolling bearing 10 with a sensor according to a first embodiment of the present invention. 1A is a cross-sectional view, and FIG. 1B is a view taken in the direction of arrow B in FIG.
As shown in FIG. 1A, the sensor-equipped rolling bearing 10 has a plurality of balls (rolling elements) 13 interposed between an outer ring 11 and an inner ring 12. The plurality of balls 13 are held by a cage 13a so as to roll freely at intervals in the circumferential direction.
Here, the outer ring 11 is a stationary wheel and the inner ring 12 is a rotating wheel.
[0009]
A seal member 14 is provided on one side (left side in the figure) of the ball 13 in the axial direction. The seal member 14 has a base end portion (outer peripheral portion) fixed to a seal groove provided in the outer ring 11, and a distal end portion (inner peripheral portion) is not in contact with the inner ring 12, and the seal member 14 is a non-contact type Is. The seal member 14 prevents leakage of a lubricant such as grease sealed between the balls 13, the outer ring 11 and the inner ring 12. Therefore, it is not necessary to increase the amount of lubricant to be enclosed more than necessary. Further, the seal member 14 prevents foreign matters such as dust from entering the bearing.
Although not shown, a contact-type seal member whose tip is in contact with the inner ring 12 may be used.
[0010]
A sensor unit 15 is provided on the other axial side of the ball 13 (right side in the figure). The sensor unit 15 has a flat portion 16a extending in the axial direction substantially flush with the outer diameter surface of the outer ring 11, and a vertical portion 16b extending radially inward from the tip of the flat portion 16a, and is formed in an L-shaped cross section. The metal plate 16 is provided. The vertical portion 16b extends inward to a radial position equivalent to the outer diameter surface of the inner ring 12, and the metal plate 16 also functions as a noise shield that blocks electromagnetic waves and the like. An annular holding block 17 for holding the sensor is disposed on the inner peripheral side of the flat surface portion 16a and the axially inner side (the ball 13 side) of the vertical portion 16b of the metal plate 16. The holding block 17 is formed of a synthetic resin or the like. A part of the holding block 17 is fitted to a step portion on the inner diameter surface of the outer ring 11, whereby the sensor unit 15 is fixed to the outer ring 11.
A plurality of sensor receiving recesses are provided on the surface of the holding block 17 facing the end surface 11a of the outer ring at intervals in the circumferential direction. A vibration sensor 18 and a temperature sensor 19 (see FIG. 1B) are held in the sensor housing recess, and the vibration sensor 18 and the temperature sensor 19 are fixed in close contact with the outer ring end surface 11a.
[0011]
The vibration sensor 18 detects abnormal vibration or the like of the bearing or its associated devices by converting a vibration component applied to the outer ring into an electric signal and transmitting it to a detection circuit. As the vibration sensor 18, for example, a piezoelectric acceleration sensor or the like can be used. The vibration sensor 18 detects axial vibration. Although not shown, a vibration sensor for detecting radial vibration can be provided separately from the vibration sensor 18.
The temperature sensor 19 constantly detects ambient temperature data in the vicinity of the ball 13, the outer ring 11, and the inner ring 12 and transmits it to a detection circuit in order to monitor whether seizure due to running out of the lubricant or the like has occurred. As the temperature sensor 19, for example, a thermocouple or a thermistor can be used.
[0012]
A rotation speed sensor 20 is provided on the inner peripheral surface of the holding block 17. The rotational speed sensor 20 is disposed in a non-contact manner on the outer peripheral side of the multipolar magnet 22 held by the magnet holding member 21 fixed to the stepped portion of the outer diameter surface of the inner ring 12. On the outer side in the axial direction of the multipolar magnet 22 (on the opposite side of the ball 13), the vertical portion 16b of the metal plate 16 is disposed in close proximity without contact.
[0013]
The multipolar magnet 22 is formed in an annular shape. On the outer diameter surface of the multipolar magnet 22, a plurality of S poles and N poles are alternately magnetized in the circumferential direction. When the multipolar magnet 22 that constantly generates magnetic force on the outer peripheral side rotates integrally with the inner ring 12, the magnetic force generated by the multipolar magnet 22 is applied to the rotational speed sensor 20 according to the rotational speed of the inner ring 12. The rotational speed of the inner ring 12 is detected. That is, the rotational speed sensor 20 generates a pulsed electric signal by the magnetic force generated by the multipolar magnet 22 and transmits it to the control circuit. Thereby, the rotation speed, rotation direction, phase, and the like of the inner ring 12 are detected. As the rotation speed sensor 20, for example, a Hall element or an MR element can be used.
The Hall element generates a detection signal whose level changes corresponding to the detected polarity of the magnetism when magnetism is detected in the energized state. The MR element has a resistance value that changes in accordance with the magnetic field strength, and an electrical detection signal can be obtained by the change in the resistance value.
[0014]
As shown in FIG. 1 (B), in this embodiment, the vibration sensor 18 and the rotational speed sensor 20 are arranged at the same circumferential position, and are shifted in the circumferential direction (the phase is shifted). The temperature sensor 19 is arranged at the position). On one imaginary line extending in the radial direction, the vibration sensor 18 is disposed on the radially outer side, and the rotational speed sensor 20 is disposed on the radially inner side.
As shown in FIG. 1A, the wirings 23 a, 23 b, 23 c extending from the sensors 18, 19, 20 are taken out through holes provided in the metal plate 16.
[0015]
According to the sensor-equipped rolling bearing 10 having the above configuration, the holding block is in a state where the vibration sensor 18 and the temperature sensor 19 held in the housing recess of the holding block 17 of the sensor unit 15 are in close contact with the end surface 11a of the outer ring 11 which is a stationary ring. 17 is fitted and fixed to the outer ring 11, and vibrations and temperature can be detected by these sensors 18 and 19 with excellent responsiveness and high sensitivity. These sensors 18 and 19 can detect abnormal vibration and an increase in bearing temperature at an early stage.
[0016]
In FIG. 2, the rolling bearing 30 with a sensor of 2nd Embodiment of this invention is shown. In the embodiments described below, members and the like having the same configurations and functions as those already described are denoted by the same or corresponding reference numerals in the drawings, and description thereof is simplified or omitted.
In the present embodiment, a seal member 14 is provided on one side (left side in the figure) of the ball 13, and a sensor unit 35 is provided on the other side (right side in the figure) of the ball 13. A stepped portion 31b is provided on the outer diameter surface of the outer ring 31 on the side where the sensor unit 35 is provided. The flat portion 36a of the metal plate 36 is fitted on the step portion 31b.
[0017]
A holding block 37 is disposed on the inner peripheral side of the flat portion 36a of the metal plate 36 and on the inner side in the axial direction of the vertical portion 36b. A plurality of sensor receiving recesses are provided on the surface of the holding block 37 that faces the end surface 31a of the outer ring with a spacing in the circumferential direction. A vibration sensor 18 and a temperature sensor (not shown) are held in the sensor housing recess, and the vibration sensor 18 and the temperature sensor are closely fixed to the outer ring end surface 31a.
[0018]
In the present embodiment, the rotational speed sensor 40 is provided on the axially inner surface (the ball 13 side) of the holding block 37 at a position protruding radially inward from the inner surface of the outer ring 31. As the rotation speed sensor 40, for example, a magnetic sensitive sensor or the like is used.
An annular magnet holding member 41 extending outward in the radial direction is fixed to the seal groove of the inner ring 32. The magnet holding member 41 also functions as a seal member that prevents leakage of lubricant and entry of foreign matter into the bearing space. A multipolar magnet 42 is provided on the entire surface of the magnet holding member 41 on the outer side in the axial direction (on the side opposite to the ball 13). Here, a rubber magnet is used as the multipolar magnet 42. The magnet holding member 41 and the multipolar magnet 42 are arranged on the inner side in the axial direction from the end faces of the inner and outer rings. The multipolar magnet 42 and the rotation speed sensor 40 are opposed to each other with a minute gap in the axial direction.
[0019]
The rubber magnet 42 is fixed to the magnet holding member 41 by adhesion or the like.
The surface of the rotational speed sensor 40 facing the multipolar magnet 42 is flush with the outer ring end surface 31a. The axial dimension of the holding block 37 is reduced and is equal to the axial dimension of the vibration sensor 18.
[0020]
According to the rolling bearing 30 with a sensor as described above, the axial dimension (width dimension) of the sensor unit 35 can be reduced, and downsizing of the bearing can be achieved.
[0021]
Note that the present invention is not limited to the above-described embodiments, and appropriate modifications and improvements can be made.
For example, as shown in FIG. 3, the vibration sensor 18, the temperature sensor 19, and the rotation speed sensor 20 may all be arranged shifted in the circumferential direction.
In the illustrated embodiment, the output line from the sensor is taken out of the sensor unit separately, but a substrate is provided in the holding blocks 17 and 37, and the output line from the sensor is connected to the substrate. The output lines may be taken out of the sensor unit all at once from the substrate.
For example, rollers or tapered rollers may be used as the rolling elements. The present invention can also be applied to double row bearings.
[0022]
【The invention's effect】
As described above, according to the present invention, it is possible to provide a rolling bearing with a sensor capable of detecting changes in vibration, temperature, etc. of the bearing with excellent responsiveness.
[Brief description of the drawings]
FIG. 1 is an enlarged view of a main part of a first embodiment.
FIG. 2 is a cross-sectional view of a second embodiment.
FIG. 3 is a cross-sectional view of a third embodiment.
FIG. 4 is a diagram for explaining a situation where the stationary wheel is cut.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10, 30 Rolling bearing with sensor 11, 31 Outer ring 11a, 31a Outer ring end face 12, 32 Inner ring 13 Ball (rolling element)
15, 35 Sensor unit 17, 37 Holding block 18 Vibration sensor 19 Temperature sensor 20 Rotation speed sensor

Claims (5)

A rolling bearing provided with a rolling element interposed between an inner ring, an outer ring, and the inner and outer rings, and used in a state where a contact angle is generated by applying a preload or an axial load, and a stationary ring among the inner and outer rings of the rolling bearing A sensor-equipped rolling bearing with a sensor unit attached to the axial end of
The sensor unit has a flat surface portion extending in the axial direction substantially flush with the outer diameter surface of the outer ring, and a vertical portion extending radially inward from the front end of the flat surface portion, and is formed in an L-shaped cross section. A metal plate is integrally provided on the inner peripheral side of the flat portion of the metal plate and on the inner side in the axial direction of the vertical portion. The metal plate is opposed to the axial end surface of the stationary wheel, and a sensor is provided at the opposite portion. A holding block made of synthetic resin provided with a housing recess;
A vibration sensor and / or a temperature sensor held in the receiving recess of the holding block,
With the sensor, the metal plate or the holding block is attached to the axial end of the stationary wheel in a state where the sensor held in the housing recess is in close contact with the axial end surface of the stationary wheel. Rolling bearing.   The rolling bearing with a sensor according to claim 1, wherein a substrate is disposed in the holding block, an output line of the sensor is connected to the substrate, and the output line is led out from the substrate.   The rolling bearing with a sensor according to claim 1 or 2, wherein the vibration sensor is capable of detecting vibration in an axial direction of the rolling bearing.   The rolling bearing with a sensor according to any one of claims 1 to 3, wherein the vibration sensor, the temperature sensor, and other sensors are arranged so as to be shifted in a circumferential direction.   The to-be-detected member is provided in the rotating wheel side among the said inner and outer rings, and the rotational speed sensor which detects the rotational speed of the said to-be-detected member is provided in the said stationary wheel side. Roller bearing with sensor.

Images