JP2003065328A - Bearing apparatus having sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bearing apparatus having a sensor, which can detect a vibration state covering a frequency range from a low frequency to a high frequency and is low-priced and compact. SOLUTION: The bearing apparatus having a sensor is assembled in a housing 2 and is provided with a rolling bearing 10 which has at least an outer ring 4 and an inner ring 6 that are relatively rotatable, and a plurality of rolling elements 8 that are assembled between the outer ring 4 and inner ring 6, and in addition, a sound wave detecting sensor 12 for detecting a vibration state of the rolling bearing 10. The sound wave detecting sensor is set to at least one or more of the outer ring, a member attached to the outer ring, the inner ring, and a member attached to the inner ring. The output from the sound wave detecting sensor is transmitted to the outside by wireless.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention detects a vibration state of a bearing incorporated in a mechanical device (for example, a moving body such as a railway vehicle, an automobile, a carrier vehicle, a machine tool such as a continuous casting machine or a rolling mill), The present invention relates to a bearing device with a sensor that can prevent the maintenance.

[0002]

2. Description of the Related Art A conventional bearing device has a housing 1 in which a rolling bearing 100 is set as shown in FIG.
02, a vibration sensor 104 and a thermometer (not shown) are provided, and a vibration wave and a temperature change generated during the operation of the rolling bearing 100 are detected by the vibration sensor 104 and the thermometer, and the detection signal is detected. It is adapted to be transmitted to the monitor 108 via the cable 106. Then, based on the detection signal transmitted to the monitor 108 at this time, the recorder 110 performs the recording and summing process of the vibration state and the temperature change, and the alarm device 112 performs the monitoring and warning process of the abnormal vibration.

[0003]

By the way, the vibration sensor 104 arranged in the conventional bearing device has a limitation in the frequency band of the vibration wave that can be detected, and therefore the vibration wave generated in the device is extremely small. In some cases, the vibration wave could not be detected with high sensitivity. For example, when the member is deformed or destroyed such that a relatively large vibration wave is generated, the conventional vibration sensor 104 can detect it. However, early signs of abnormal vibration such as microdeformation, microcracks, wear, and peeling appear before the deformation or destruction of the members. At this time, the vibration is a small elastic wave of a high frequency component of several 10 kHz or more. (High frequency vibration), the vibration state could not be detected with high sensitivity. As a result, even if an abnormality occurs in the rolling bearing 100 for the first time, the sign of the abnormality cannot be detected at an early stage, and it is difficult to preventively maintain the device. Particularly, in the rolling bearing 100 during low-speed rotation, the vibration wave generated in the device becomes extremely small, so that it is difficult for the vibration sensor 104 as described above to detect the vibration wave with high accuracy. However, the abnormality of the bearing cannot be grasped at an early stage, and the temperature rise in the device hardly appears on the thermometer, so that it is not possible to grasp the sign of abnormality such as seizure at an early stage. Further, in the conventional bearing device, detection signals from the vibration sensor 104 and the thermometer are transmitted via the cable 106.
In this case, if the number of installed vibration sensors 104 and thermometers increases, it is necessary to increase the number of cables 106 correspondingly. As a result, the wiring process of the cables 106 becomes complicated, and the number of parts for wiring process is increased. Will increase the manufacturing cost of the device. Furthermore, since it is necessary to secure a space for wiring the cable 106 in the device, the device becomes larger by that amount. Further, when a large external vibration is applied, the cable 106 may be broken and it may become impossible to transmit and receive a signal. The present invention has been made to solve such a problem, and an object thereof is to provide a low-cost and compact bearing device with a sensor capable of detecting a vibration state from a low frequency to a high frequency. It is in.

[0004]

In order to achieve such an object, a bearing device with a sensor according to the present invention comprises an outer ring and an inner ring that are rotatable relative to each other, and a plurality of bearings mounted between these outer and inner rings. With a rolling bearing having at least the rolling element of, the sound wave detection sensor for detecting the vibration state of this rolling bearing is provided, the sound wave detection sensor, the outer ring, a member attached to the outer ring, It is characterized in that it is set in at least one or more of the inner ring and a member attached to the inner ring, and the output of this sound wave detection sensor is transmitted to the outside wirelessly. The sound wave detection sensor converts a mechanically generated vibration wave into an electric signal. Further, the sound wave detection sensor is set in a state of being incorporated in the sensor holder, and the sensor holder is provided with an amplification circuit for amplifying the output of the sound wave detection sensor. The sensor holder is provided with a comparator that compares the output of the sound wave detection sensor with a reference value and a counter that counts the number of times that the output of the sound wave detection sensor exceeds the reference value within a predetermined time. The sensor holder is provided with a transmission circuit capable of converting the output of the sound wave detection sensor into a signal wave having a predetermined frequency component and transmitting the signal wave to the outside. The signal waves are radio waves, light waves, and ultrasonic waves having a predetermined frequency component.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A bearing device with a sensor according to an embodiment of the present invention will be described below with reference to the accompanying drawings. In the following description, a ball bearing is illustrated and described as an example, but the present invention is not limited to this, and it goes without saying that the present invention can be applied to tapered roller bearings, cylindrical roller bearings, and angular ball bearings. Yes. As shown in FIG. 1, the bearing device with a sensor according to the present embodiment is incorporated in a housing 2, and has an outer ring 4 and an inner ring 6 which are relatively rotatable with respect to each other, and a plurality of parts which are incorporated between these outer and inner rings. The rolling bearing 10 having at least the rolling element 8 is provided, and a sound wave detection sensor 12 for detecting the vibration state of the rolling bearing 10 is provided. The sound wave detection sensor 12 includes the outer ring 4 and the outer ring. 4 is set to at least one of the member (for example, the housing 2) attached to the inner ring 6, the inner ring 6, and the member (for example, the shaft 14) attached to the inner ring 6, and the output of the sound wave detection sensor 12 is wirelessly transmitted to the outside. It is like this. In the present embodiment, the housing 2 is attached to the outer ring 4 and the inner ring 6
A shaft 14 is attached to. In this case, it is possible to select either an outer ring rotation (inner ring stationary) system for rotating the outer ring 4, an inner ring rotation (outer ring stationary) system for rotating the inner ring 6, or a system for rotating the outer ring 4 and the inner ring 6 relative to each other. Is. Further, other bearing configurations such as a cage (not shown) and a sealing plate (contact or non-contact seal or shield) 16 can be selected as needed.

The sound wave detection sensor 12 is constructed so as to be capable of converting a mechanically generated vibration wave having a frequency of several tens of kHz or more into an electric signal. Specifically, a vibration wave is detected, this vibration wave is replaced with a change in voltage level, and an electric signal corresponding to the voltage value at that time is output. As the vibration wave, a bearing device with a sensor (rolling bearing 1
The vibration wave generated during operation 0), the vibration wave generated from the bearing device with the sensor (rolling bearing 10) due to an external impact, and the like are assumed. Such an oscillating wave has various frequency characteristics depending on the behavior of the oscillating source, for example, an oscillating wave of a low frequency component which is relatively easy to detect, and an oscillating wave of an extremely small high frequency component. Especially, the vibration wave of high frequency component is
The members (for example, the outer ring 4, the members attached to the outer ring 4, the inner ring 6, and the members attached to the inner ring 6) constituting the bearing device with a sensor (rolling bearing 10) are slightly deformed before they are deformed or destroyed. It appears as an early sign of abnormal vibration such as micro cracks, wear and peeling. The vibration wave at this time becomes an elastic wave (elastic wave in the ultrasonic region) of a high-frequency component having a minute frequency of several tens of kHz or more. Therefore, in order to detect the vibration state with high sensitivity, in the present embodiment, a sound wave is used. The detection sensor 12 is used. In this case, the sound wave detection sensor 1
As 2, a generally known AE (acoustic emission) sensor can be used. Note that the drawing shows an AE sensor 12 as an example of the sound wave detection sensor 12.

The sound wave detection sensor (AE sensor) 12 is set in a state of being incorporated in the sensor holder 18, and in the sensor holder 18, an amplification circuit 20 for amplifying the output of the sound wave detection sensor 12, and this amplification circuit 20 are used. A transmission circuit 22 for transmitting the amplified output of the sound wave detection sensor 12 to the outside.
Etc. (see FIG. 2) are provided. The transmission circuit 22 is
The output of the sound wave detection sensor 12 can be converted into a signal wave of a predetermined frequency component and wirelessly transmitted to the outside. The signal wave can be radio waves, light waves, ultrasonic waves, etc. with a predetermined frequency component, but it can be set to signal waves with various frequency components according to the purpose of use of the bearing device with sensor and the usage environment. Is. As a method of setting the sensor holder 18 in which the sound wave detection sensor 12 is incorporated, the sensor holder 18 is mounted on the outer ring 4, a member attached to the outer ring 4 (for example, the housing 2), the inner ring 6, and a member attached to the inner ring 6 (for example, The method is not particularly limited as long as it can be securely fixed to the shaft 14), and various methods such as a method of adhering with an adhesive, screwing, and fitting can be adopted. In the present embodiment, as an example, the sensor holder 18 is attached to the housing 2.
Is fixed. In the configuration as described above, the vibration wave generated during the operation of the bearing device with sensor (rolling bearing 10) is detected by the sound wave detection sensor (AE sensor) 12, and the detection signal is amplified by the amplification circuit 20. After that, it is converted into a predetermined frequency component by the transmission circuit 22 and wirelessly transmitted to the outside. At this time, the controller 24
Controls the recorder 26 on the basis of the detection signal wirelessly transmitted from the sensor holder 18 to perform recording and aggregation processing of the vibration state of the sensor-equipped bearing device (rolling bearing 10), and also to control the alarm device 28. Then, the monitoring warning process of the sensor-equipped bearing device (rolling bearing 10) is performed.

As described above, according to the present embodiment, by using the sound wave detection sensor (AE sensor) 12, a wide range of vibration waves ranging from very small vibration waves to large vibration waves can be detected with high sensitivity. You can In particular, even in a rolling bearing during low-speed rotation, it is possible to detect with high sensitivity early signs of abnormal vibration such as micro-deformation or micro-cracks before wear or peeling of a member, or deformation or breakage of the member. As a result, it becomes possible to early detect the sign that an abnormality has started to occur in the sensor-equipped bearing device (rolling bearing 10), and preventive maintenance of the device can be achieved in advance. Furthermore, in the present embodiment, since the output of the sound wave detection sensor (AE sensor) 12 is wirelessly transmitted, various cables as in the related art are not required, so that the manufacturing cost can be reduced. Further, since it is not necessary to secure a space for wiring the cable in the device, the device can be made compact. It should be noted that the present invention is not limited to the above-described embodiment, but can be variously modified as follows. For example, as shown in FIG. 3, in the sensor holder 18, a comparator 30 that compares the output of the sound wave detection sensor (AE sensor) 12 with a reference value, and the output of the sound wave detection sensor 12 exceeds the reference value within a predetermined time. A counter 32 for counting the number of times is added and the counted number is transmitted by the transmission circuit 2
It may be transmitted to the outside at 2. The reference value can be set in advance by the reference value setting circuit 34 arbitrarily (purpose of use of the device, environment of use, etc.). According to such a modified example, not only the same effects as the effects of the above-described embodiment can be obtained, but also by setting the reference value,
It is possible to detect the number of occurrences of abnormal vibration and the magnitude of vibration in detail. The function of the alarm device 28 may be incorporated into the sensor holder 18, and the alarm output may be transmitted by the transmission circuit 22 when the count number of the counter 32 exceeds a certain value. Further, if a bandpass filter is inserted between the amplification circuit 20 and the comparator 30 to detect the number of occurrences of abnormal vibration of only a specific frequency, more detailed detection becomes possible. It should be noted that the frequency of the bandpass filter may be appropriately selected depending on the detection target. Further, by providing a plurality of bandpass filters, it is possible to detect the number of times of occurrence of abnormal vibrations in a plurality of frequency bands in more detail, and more detailed detection is possible. Although not particularly described in the above-mentioned embodiment, the sensor holder 18 is supplied with a power source (not shown) such as a battery.
Alternatively, a power generation mechanism (not shown) such as a solar cell may be installed. With this configuration, each circuit configuration (for example, the sound wave detection sensor (AE sensor) 12 and the amplification circuit 2 incorporated in the sensor holder 18 does not require an external power source.
0, the transmission circuit 22, etc.) can be controlled, so that the degree of freedom of the mounting position of the sensor holder 18 can be improved. Further, a magnet (not shown) is arranged in a rotating portion (for example, the outer ring 4, the inner ring 6 and the like) of the bearing device with a sensor (rolling bearing 10), and a stationary portion facing the magnet (not shown) is attached to the outer ring 4 if the inner ring is rotating. If the housing 2 is rotated, and if the outer ring is rotated, a coil (not shown) is arranged on the shaft 14 attached to the inner ring 6) to configure a generator, and this generator drives and controls each circuit configuration of the sensor holder 18. You may. In this case, it is preferable to install a battery as a secondary battery.

[0009]

According to the present invention, it is possible to realize a low-cost, compact bearing device with a sensor capable of detecting a vibration state from a low frequency to a high frequency.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a bearing device with a sensor according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a circuit configuration of a sensor holder incorporating a sound wave detection sensor (AE sensor).

FIG. 3 is a block diagram showing a circuit configuration of a sensor holder according to a modified example of the invention.

FIG. 4 is a diagram showing a configuration of a conventional bearing device.

[Explanation of symbols]

2: Housing 4: Outer ring 6: Inner ring 8: Rolling element 10: Rolling bearing 12: Sound wave detection sensor (AE sensor)

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G08C 23/02 G08C 23/00 B 23/04 C F term (reference) 2F073 AA35 AB02 BB01 BC02 BC04 BC05 CC01 CC08 EE11 GG05 2G024 AC01 BA01 CA13 2G064 AA17 AB02 BA15 CC12 CC54 3J101 AA02 AA42 AA52 AA62 FA24 FA48 GA01 GA31 GA35 GA36

Claims (6)

[Claims] 1. A rolling bearing having at least an outer ring and an inner ring rotatable relative to each other and a plurality of rolling elements incorporated between the outer and inner rings, and detecting a vibration state of the rolling bearing. Is provided for at least one of the outer ring, the member attached to the outer ring, the inner ring, and the member attached to the inner ring, and the output of this sound wave detection sensor is provided. Is transmitted wirelessly to the outside by a bearing device with a sensor. 2. The bearing device with sensor according to claim 1, wherein the sound wave detection sensor converts a mechanically generated vibration wave into an electric signal. 3. The sound wave detection sensor is set in a state of being incorporated in a sensor holder, and the sensor holder is provided with an amplification circuit for amplifying an output of the sound wave detection sensor. 2. The bearing device with a sensor according to 2. 4. The sensor holder is provided with a comparator for comparing the output of the sound wave detection sensor with a reference value and a counter for counting the number of times the output of the sound wave detection sensor exceeds the reference value within a predetermined time. The bearing device with a sensor according to claim 3, wherein 5. The sensor holder is provided with a transmission circuit capable of converting the output of the sound wave detection sensor into a signal wave of a predetermined frequency component and transmitting the signal wave to the outside. Alternatively, the bearing device with the sensor according to item 4. 6. The bearing device with a sensor according to claim 5, wherein the signal wave is an electric wave, a light wave, or an ultrasonic wave having a predetermined frequency component.