JP2003307228A - Bearing device with sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bearing device with a sensor easily installable without taking into consideration the wiring of a signal conductor, an electric wire cable and the like. <P>SOLUTION: This bearing device 1 with the sensor has an outer ring 9 and inner rings 10a and 10b (a set of bearing rings) for relatively rotating by a plurality of rolling bodies 8, and a wireless sensor (a sensor) 7 installed on the outer ring (the first bearing ring) 9 or a member fixed to the outer ring 9. The wireless sensor 7 is formed by arranging a detecting part 14 for detecting a measuring object, a communication device 16 for outputting a signal detected by the detecting part 14 or the information of processing the signal by radio transmission R, and a power source 17 for supplying electric power to at least the communication device 16 of the detecting part 14 and the communication device 16 in a sensor holder 13. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bearing device with a sensor used for bearings of vehicles such as railroad cars and automobiles, or industrial machines such as rolling mills.

[0002]

2. Description of the Related Art Axles of vehicles such as automobiles and railway cars, and bearings of industrial machines such as rollers of rolling mills and movable shafts of machine tools detect vibration, temperature, rotational speed, etc. in order to grasp the operating state. A sensor is attached.

FIG. 7 shows a conventional bearing device 50 with a sensor. In this bearing device with sensor 50, a rotation speed sensor 52 and a temperature sensor 53 are attached to detect the rotation speed and temperature of the bearing 51. FIG. 7A
As shown in FIG. 5, the rotation speed sensor 52 includes a cap 56 fixed to the housing 55 so as to cover the end of the rotating shaft 54.
Installed on. Further, the temperature sensor 53 is the bearing 5
It is attached to the housing 55 at a position close to 1. The rotation speed sensor 52 and the temperature sensor 53 are connected to the control device 57 by a signal line 58. A tone ring 59 is attached to the end of the shaft 54. Tone ring 59
7A includes a collar 60 extending in the radial direction from the shaft 54 as shown in FIG. 7A, and teeth 61 are provided on the outer edge of the collar 60 at regular intervals as shown in FIG. 7B. ing.
The rotation speed sensor 52 has the tone ring 5 at the tip 52a.
It is arranged so as to face the teeth 61 of the nine. The shaft 54 rotates, and the teeth 61 of the tone ring 59 move to rotate the speed sensor 5
The rotation speed sensor 52 detects the tooth 61 by passing the second tip 52a. The signals detected by the rotation speed sensor 52 and the temperature sensor 53 are sent to the controller 57.
Is processed in.

[0004]

However, when the rotational speed and temperature of the bearing 51 are measured by the above method,
The signals detected by the sensors 52 and 53 are output by the signal line 58. Therefore, the signal line 58 must be wired between each sensor 52, 53 and the control device 57 according to the number of sensors. Further, in vehicles such as automobiles and railroad cars, and industrial machines such as rolling mills and machine tools, it is desirable to simultaneously and comprehensively monitor the states of a plurality of bearings.
If the wiring from the rotation speed sensor or temperature sensor of each bearing to the controller becomes complicated and the signal line is broken,
The work of replacing the signal line becomes complicated.

Therefore, an object of the present invention is to provide a bearing device with a sensor which can be easily provided without considering the wiring of signal lines, electric cables and the like.

[0006]

A bearing device with a sensor according to the present invention includes a set of bearing rings that relatively rotate via a plurality of rolling elements, and a first bearing of the pair of bearing rings. The sensor is provided with a wheel or the first bearing ring and a sensor attached to a fixed member, and the sensor wirelessly outputs a detection unit that detects a measurement target and a signal detected by the detection unit or information obtained by processing the signal. The sensor holder is provided with the communication device, the power supply that supplies power to at least the communication device of the detection unit and the communication device.

Alternatively, the sensor-equipped bearing device according to the present invention includes a set of bearing rings that relatively rotate via a plurality of rolling elements, and a first bearing ring of the pair of bearing rings or the first bearing ring. A sensor attached to a member fixed to the first bearing ring, and a second magnetic flux fluctuation that is attached to a second bearing ring rotating relative to the first bearing ring or a member fixed to the second bearing ring and faces the sensor. And a second magnetic flux variation means for varying the magnetic flux density passing through the coil by changing the relative position of the detection unit, the coil, and the first magnetic flux variation means. The sensor holder includes a communication device that wirelessly outputs a signal detected by the detection unit or information obtained by processing the signal, and a power supply that supplies power to at least the communication device of the detection unit and the communication device.

Further, in order to monitor the operating state of the bearing device with sensor, at least one of a rotation speed sensor, a temperature sensor and a vibration sensor is included in the detecting portion.

Further, the communication device outputs the signal detected by the detector or the information obtained by processing the signal by either radio wave, light or ultrasonic wave in accordance with the environment around the bearing device with sensor.

When a plurality of bearing devices with sensors are used at the same time, in order to identify and receive signals or information output from the bearing devices with sensors, the communication device, together with the signals or information to be output, Unique identification information is output to at least one of the bearing device with the sensor and the detection unit.

Further, in order to supply stable electric power for a long period of time, the power source includes a generator, a charging circuit and a secondary battery. In this case, the generator is a photoelectric conversion element or a thermoelectric generation element.

The coil and the first and second magnetic flux changing means are
The device is simplified by using both the rotation speed sensor and the generator.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment of the present invention will be described with reference to FIGS. 1 and 2 by taking a bearing device with a sensor 1 applied to a bearing for a vehicle as an example. A bearing device with a sensor 1 shown in FIG. 1 includes a housing 2, a bearing 3, and an axle 4.
A tone ring 5, an end cap 6, and a wireless sensor 7. The bearing 3 includes tapered rollers 8 that are a plurality of rolling elements, an outer ring 9 and a pair of inner rings 10 that are a pair of race rings that relatively rotate through the tapered rollers 8.
a and 10b. The outer ring 9 is fixed to the housing 2, and the inner rings 10a and 10b support the axle 4. A spacer 11 is inserted between the inner rings 10a and 10b, and the bearing 3 can be replaced by a spacer having a different width.
The preload of can be adjusted. The tone ring 5 is fitted to the end 4a side of the axle 4 adjacent to the inner ring 10a, and is fixed by being pressed against the inner ring 10a by the inner ring presser hardware 12. The tone ring 5 has a flange 5a extending in the radial direction. Outer edge portion 5 of this flange 5a
Teeth 5c are formed on b at equal intervals along the circumferential direction. The tooth 5c functions as a first magnetic flux changing means. The end cap 6 is the axle 4 to which the tone ring 5 is attached.
Is attached to the housing 2 so as to cover the end 4a of the. The wireless sensor 7 is a tooth 5c of the tone ring 5.
The end cap 6 is attached at a position opposed to. When the axle 4 rotates, the wireless sensor 7
And the tooth 5c of the tone ring 5 pass each other.

The wireless sensor 7 includes a sensor holder 13
2, the detection unit 14, the signal processing circuit 15, the communication device 16, the power supply 17, which are housed in the sensor holder 13,
And a lid 19 to which the antenna 18 is attached.
Tip portion 13a of the sensor holder 13 close to the tone ring 5
Has a step and is thin. Wireless sensor 7
Hole 20 provided in the end cap 6 for inserting the
The opening 20a on the tone ring 5 side of the sensor holder 1
3 is narrowed along the shape of the tip portion 13a. When the wireless sensor 7 is attached, the wireless sensor 7 does not enter too much inside the end cap 6, so that the tip of the wireless sensor 7, in the present embodiment, the tip ring 13a of the sensor holder 13 interferes with the tone ring 5. Can be prevented. Base end portion 13b of the sensor holder 13
Has a straight screw portion 13c formed on the outer circumference and a tapered screw portion 13d formed on the inner circumference. The straight screw portion 13c is attached with a fixing metal fitting 21 and an anti-rotation nut 22 formed with a female screw to be screwed with the straight screw portion 13c. The sensor holder 13 is inserted into the hole 20 of the end cap 6 with the fixing metal fitting 21 screwed on. After fixing the fixing metal fitting 21 to the end cap 6 with a bolt or the like at a position not shown, the sensor holder 13 is rotated to adjust the distance between the tip portion 13a and the tone ring 5, and the fixing nut 22 is fixed.

The detector 14 includes a rotation speed sensor 23, a vibration sensor 24, and a temperature sensor 25.

The rotation speed sensor 23 is arranged inside the tip portion 13a of the sensor holder 13 near the tone ring 5. The rotation speed sensor 23 includes a magnet 26 and an active type element such as a hall element 27 that detects a change in magnetic flux density. An MR (Magneto Resistance) element or a G element is used as an element for detecting a change in magnetic flux density.
An MR (Giant Magneto-Resistance) element may be used. When the tone ring 5 rotates with the axle 4, the magnetic field formed by the magnet 26 is changed by the teeth 5 c of the tone ring 5. The magnet 26 functions as a second magnetic flux changing means. The rotation speed sensor 23 detects the change in the magnetic flux density of the magnetic field with the hall element 27. The rotation speed sensor 23 can obtain a detection signal when the hall element 27 is energized even when the axle 4 is not rotating. When using a tone ring including a multi-pole magnet in which N poles and S poles are alternately magnetized at equal intervals instead of teeth, the magnet 26 of the rotation speed sensor may be omitted.

The vibration sensor 24 is firmly fixed so as not to move inside the sensor holder 13. The vibration sensor 24 is, specifically, a cantilever-supported piezoelectric element having a bimorph structure. Instead of the bimorph structure piezoelectric element, a leaf spring having strain gauges attached to the front and back surfaces may be used.

The temperature sensor 25 is attached to the inner surface of the sensor holder 13 near the bearing 3. Specific examples of the temperature sensor 25 include a thermistor, an IC temperature sensor, a resistance temperature detector, and a thermocouple.

The signal processing circuit 15 processes the signals detected by the rotation speed sensor 23, the vibration sensor 24, and the temperature sensor 25 of the detection unit 14, and outputs detection information. In addition to the processed detection information, each sensor 23, 24,
25, or if the identification information unique to the detection unit 14 is output, the detection information can be easily identified.

The communication device 16 outputs the detection information processed by the signal processing circuit 15 as a radio wave R from the antenna 18.
The radio wave R may be analog or digital, and may be of amplitude modulation type or frequency modulation type. In addition, the output radio wave R is once received by a repeater, and from the repeater, a public telephone line, PHS (Personal Handyphone System), mobile phone, etc. are used to detect the location far from the bearing device with sensor 1. You can also send information. Therefore, for example, when the bearing device with a sensor 1 is applied to a railway vehicle, not only the radio wave R transmitted from the bearing device with a sensor 1 is received and monitored in a driver's cab or a palm room, but also in a command center or the like.
It is also possible to integrally manage a plurality of vehicles.

The power supply 17 includes a detector 14 and a signal processing circuit 1.
5. Supply power to the communication device 16. The power supply 17 may be a primary battery or a power supply unit including a generator such as a photoelectric conversion element or a thermoelectric generator, a charging circuit, and a secondary battery. Further, when the power source capacity of the power source 17 is small or the power generation amount of the generator is small, the wireless sensor 7 does not always perform detection, but performs detection at constant time intervals. In other cases, the detection unit 14, Signal processing circuit 1
5. Power control such as not supplying power to the communication device 16 is performed. This makes it possible to use a battery or a generator having a small capacity or ability, and the wireless sensor 7 can be miniaturized.

In the bearing device with a sensor 1 configured as described above, signals of the rotation speed, vibration, and temperature of the axle 4 detected by the detection unit 14 or detection information obtained by processing these signals by the signal processing circuit 15 is used as a communication device. Since it is output from 16 by radio wave R,
No need for signal lines. In addition, the power supply 17 is connected to the sensor holder 13
Since it is housed in, there is no need for electric cables to supply power. Therefore, the bearing device with a sensor 1 can be provided in a vehicle, a mechanical device, or the like without considering wiring. When a plurality of sensor-equipped bearing devices 1 are used at the same time, the sensor-equipped bearing device 1 can be easily installed because there is no wiring such as signal lines and power cables. Further, the bearing device with sensor 1 includes the rotation speed sensor 23 and the vibration sensor 2.
4. Since the wireless sensor 7 in which the temperature sensor 25 is housed in one sensor holder 13 is provided, the housing 2
It is possible to reduce the processing of the part to which the sensor is attached such as or the end cap 6.

A sensor-equipped bearing device according to a second embodiment of the present invention will be described with reference to FIGS. 4 to 6. The same components as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

The sensor-equipped bearing device 31 shown in FIG. 4 includes a passive type rotational speed sensor 32 in the detecting portion 14 of the wireless sensor 7. The rotation speed sensor 32 includes a coil 33, a pole piece 34, and a magnet 2 as shown in FIG.
6 and is arranged in the tip portion 13a of the sensor holder 13. The coil 33 is arranged with the central axis line facing the tone ring 5. The pole piece 34 is passed through the coil 33, one end 34 a is directed to the tone ring 5, and the magnet 26 is attached to the other end 34 b.
The tone ring 5 is an example of a first magnetic flux changing means,
The pole piece 34 and the magnet 26 are an example of second magnetic flux changing means. The pole piece 34 may be a member that guides a magnetic flux, for example, a member containing iron as a main component, preferably a rod-shaped component made of a ferromagnetic material. When a tone ring including a multi-pole magnet in which N poles and S poles are alternately magnetized at equal intervals is used instead of the teeth 5c, the magnet 26 of the rotation speed sensor 32 may be omitted.

When the tone ring 5 rotates together with the axle 4, the teeth 5c of the tone ring 5 pass the tip 13a of the sensor holder 13. This causes the teeth 5c of the tone ring 5 to cross the magnetic field extending from the pole piece 34,
A change occurs in the magnetic field of the pole piece 34, that is, the magnetic flux density passing through the inside of the coil 33. When the magnetic flux density passing inside the coil 33 changes, an induced current is generated in the coil 33. The rotation speed sensor 32 detects the induced current generated in the coil 33 and outputs it as a signal related to the rotation speed. The pole piece 34 and the magnet 26 are magnetic flux changing means for changing the magnetic flux density passing through the coil 33 when the tone ring 5 passes the tip portion 13a of the sensor holder 13.

Further, the rotation speed sensor 32 is connected to the charging circuit 35 as shown in FIG. 6 because an induced current is generated in the coil 33 when the tone ring 5 rotates.
Used as a generator. The charging circuit 35 includes the secondary battery 3
Connected to 6. Rotational speed sensor 32 and charging circuit 3
5 and the secondary battery 36 constitute a power source 37.

Since the induced current generated in the coil 33 is alternating current, the charging circuit 35 converts it into direct current. The converted direct-current power charges the secondary battery 36 and is supplied to the signal processing circuit 15 and the communication device 16.
When the rotation of the axle 4 is stopped, the electric power stored in the secondary battery 36 is supplied to the signal processing circuit 15 and the communication device 16. Therefore, the sensor-equipped bearing device 31 is mounted on the axle 4
Even when is not rotating, the signal processing circuit 15 processes the signals detected by the vibration sensor 24 and the temperature sensor 25,
The communication device 16 can output detection information and identification information. Further, since the bearing device with sensor 31 includes the rotation speed sensor 32 serving as a power generator, the charging circuit 35, and the secondary battery 36 in the power supply 37, it is possible to supply stable output power and at the same time, supply power. It is not necessary to replace 37.

In the first and second embodiments, the communication device 16 outputs the detection information and the identification information by the radio wave R, but the device that receives the detection information is in the line of sight from the communication device 16. If it is in a good range, you may communicate using light or ultrasonic waves. Also, bearing devices with sensors 1, 3
If 1 is covered with a member that blocks radio waves or light,
It is good to communicate using ultrasonic waves.

A determination circuit for determining whether or not the signal detected by the detection unit exceeds a preset threshold value, and a diagnostic circuit for outputting information based on the determination result are provided together with the signal processing circuit. Good.

Further, when the information of the sensor-equipped bearing devices 1 and 31 is required, a command signal for requesting the sensor-equipped bearing devices 1 and 31 for detection information is provided together with a unique identification of each sensor-equipped bearing device 1 and 31. A signal may be transmitted and the detection information may be output from the bearing devices 1 and 31 with sensors.

Although the sensor-equipped bearing devices 1 and 31 of the first and second embodiments have been described as being applied to a bearing device for a vehicle in which tapered rollers are used as rolling elements, rolling balls or cylindrical rollers are used. It may be applied to a bearing device as a moving body. Further, since the sensor-equipped bearing devices 1 and 31 output the detected signal wirelessly, they can be attached to the rotating bearing ring.

The shape of the sensor holder 13 is not limited to the shape shown in the embodiment, and may be a stepless cylindrical shape or a box shape. In addition, the wireless sensor 7 attached to the bearing device with sensor 1, 31 is mounted on a movable body of the linear motion device, for example, a bearing, and corresponds to the tone ring 5.
It is also possible to apply the magnetic flux changing means by attaching it to a track of a linear motion device, for example, a rail of a linear guide or a screw shaft of a ball screw.

[0033]

According to the bearing device with a sensor of the present invention, since the communication device wirelessly outputs the signal detected by the detector or the information obtained by processing the signal, no signal line is required. Further, since a power supply for supplying power to the communication device is provided, an electric wire cable is also unnecessary. Further, when using a plurality of sensor-equipped bearing devices at the same time, there is no wiring, so there is no need for a wiring space and wiring work. Therefore, when installing a bearing device with a sensor in a vehicle or mechanical device,
It can be easily provided without considering the wiring of signal lines and electric cables.

[Brief description of drawings]

FIG. 1 is a sectional view showing a bearing device with a sensor according to a first embodiment of the present invention.

FIG. 2 is a block diagram of a wireless sensor of the bearing device with sensor of FIG.

FIG. 3 is a cross-sectional view of the wireless sensor showing an enlarged F3 portion in FIG.

FIG. 4 is a sectional view showing a bearing device with a sensor according to a second embodiment of the present invention.

5 is a perspective view showing a rotation speed sensor of the bearing device with the sensor of FIG. 4 and its surroundings.

6 is a block diagram of a wireless sensor of the bearing device with sensor of FIG.

FIG. 7A is a cross-sectional view of the conventional bearing taken along the line AA in FIG. (B) is a side view of the conventional bearing shown along BB in (A).

[Explanation of symbols]

1,31 ... Bearing device with sensor 5 ... Tone ring (first magnetic flux changing means) 7 ... Wireless sensor (sensor) 8 ... Tapered roller (rolling element) 9 ... Outer ring (first bearing ring) 10a, 10b ... Inner ring (second bearing ring) 13 ... Sensor holder 14 ... Detector 16 ... Communication device 17, 37 ... Power supply 23, 32 ... Rotation speed sensor 24 ... Vibration sensor 25 ... Temperature sensor 26 ... Magnet (second magnetic flux changing means) 33 ... Coil 34 ... Pole piece (second magnetic flux changing means) 35 ... Charging circuit 36 ... Secondary battery R ... radio wave

─────────────────────────────────────────────────── ─── Continuation of 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 AA02 AA35 AB02 BB02 BC02 BC04 BC05 CC01 EE12 FF02 FF08 GG01 GG04 3J101 AA01 AA62 BA53 BA54 BA56 BA77 FA22 FA23 FA24 FA26 FA46 FA48 FA55 GA02 GA31 GA36

Claims (10)

[Claims] 1. A relative rotation 1 through a plurality of rolling elements.
A pair of bearing rings, and a sensor attached to a first bearing ring of the pair of bearing rings or a member fixed to the first bearing ring, the sensor including a detection unit for detecting a measurement target; A sensor holder is provided with a communication device that wirelessly outputs a signal detected by the detection unit or information obtained by processing the signal, and a power supply that supplies power to at least the communication device among the detection unit and the communication device. Bearing device with sensor. 2. A device that relatively rotates through a plurality of rolling elements 1
A set of bearing rings, a sensor mounted on a first bearing ring of the pair of bearing rings or a member fixed to the first bearing ring, and a second bearing ring that rotates relative to the first bearing ring Alternatively, the first magnetic flux fluctuation means is provided which is mounted on a member fixed to the second bearing ring and faces the sensor, and the sensor detects a measurement target, a coil, and the first magnetic flux fluctuation. Second magnetic flux changing means for changing the magnetic flux density passing through the coil by changing the relative position to the means, a communication device for wirelessly outputting a signal detected by the detection unit or information obtained by processing the signal, A bearing device with a sensor, wherein a detection unit and a power supply for supplying electric power to at least the communication device in the communication device are provided in a sensor holder. 3. The bearing device with a sensor according to claim 1 or 2, wherein the detection unit includes a rotation speed sensor for detecting a rotation speed, a temperature sensor for detecting a temperature, and a vibration sensor for detecting a vibration. At least one of them is included. 4. The bearing device with a sensor according to claim 1, wherein the communication device uses a signal detected by the detection unit or information obtained by processing the signal as an electric wave and an optical signal. And output by either of the ultrasonic waves. 5. The bearing device with a sensor according to claim 1, wherein the communication device, together with the signal or the information to be output, the bearing device with the sensor and the detection unit. And output identification information unique to at least one of the above. 6. The bearing device with a sensor according to any one of claims 1 to 5, wherein the power source includes a generator, a charging circuit, and a secondary battery. 7. The bearing device with a sensor according to claim 6, wherein the generator is a photoelectric conversion element or a thermoelectric generation element. 8. The bearing device with a sensor according to claim 2, wherein the coil and the first and second magnetic flux changing means serve as a rotation speed sensor and a generator. 9. The bearing device with a sensor according to claim 1, wherein the first bearing ring is a fixed ring fixed to the housing. 10. The bearing device with a sensor according to claim 1, wherein the first bearing ring is a rotary ring fixed to a rotary shaft.