JP2002357220A - Rolling bearing unit with rotation detecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To integrate a rotation detecting sensor 27a, and a temperature sensor 29a and vibration sensor 33 in order to detect temperature and vibration of a rolling bearing such as a double-row tapered roller bearing 3 and the like, and to reduce cost by reducing the numbers of the components and the cables as well as propelling compact and lightweight design. SOLUTION: Integrating the rotation detecting sensor 27a, the temperature sensor 29a, and the vibration sensor 33, the integrated is set as a sensor unit. The sensor unit is combined and supported on an outer periphery of a seal case 17a installed in an outer ring by means of an installing flange portion, screws, and an anchor member 55.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION A rolling bearing unit with a rotation detecting device according to the present invention comprises a rotating shaft of wheels of a railway vehicle or an automobile or a rotating shaft of various industrial machinery such as a rolling mill, a vehicle body or a support base. It is rotatably supported by a fixed part such as the like, and is used for detecting one or more states selected from among the rotational speed, temperature, and vibration of the rolling bearing unit in the operating state.

[0002]

2. Description of the Related Art For example, a rolling bearing unit is used to rotatably support an axle provided with wheels of a railway vehicle with respect to a bearing box fixed to the railway vehicle. In addition, in order to determine the traveling speed of a railway vehicle or to perform sliding control for preventing uneven wear of the wheels, it is necessary to detect the rotational speed of the wheels. Further, in order to prevent the occurrence of an abnormality in the rolling bearing unit and seizure of the rolling bearing unit, it is necessary to detect the temperature of the rolling bearing unit. For this reason, a rotation detection sensor and a temperature sensor are incorporated in the rolling bearing unit,
In recent years, the rotation support device with a sensor rotatably supports the wheel with respect to the bearing housing, and detects the rotation speed of the wheel and the temperature of the rolling bearing unit in recent years.

FIGS. 12 and 13 show an example of a conventional structure of a rotary support device with a sensor for such a railway vehicle. An axle 1, which is a rotating shaft that rotates during use with a wheel (not shown) supported and fixed, includes a bearing housing 2 that does not rotate during use.
Is rotatably supported by a double row tapered roller bearing 3 as a rolling bearing. The double-row tapered roller bearing 3 is arranged concentrically with the outer ring 4 as a stationary wheel and a pair of inner rings 5 as a rotating wheel according to claim
And a plurality of tapered rollers 6, 6 each of which is a rolling element
And The outer race 4 is formed in a cylindrical shape as a whole, and a double-row outer raceway 7 which is a stationary raceway is provided on the inner peripheral surface.
Having. Each of the outer raceways 7 has a conical concave shape, and is inclined in such a direction that the inner diameter increases toward the axial end of the outer race 4.

Each of the pair of inner races 5 is formed in a substantially short cylindrical shape, and an inner raceway 8 having a conical convex shape, which is a rotating raceway, is formed on each outer peripheral surface. I have. Each of the inner rings 5 is arranged concentrically with the outer ring 4 on the inner diameter side of the outer ring 4 with the end faces on the smaller diameter side facing each other. Furthermore, each of the above tapered rollers 6,
6 is between the outer raceway 7 and the inner raceway 8,
A plurality of each are provided so as to roll freely while being held by the holder 9. In addition, a bearing box provided on the suspension device side for supporting the axle of the railway vehicle is shown in FIGS. As described above, there are many structures having a saddle shape with the lower part opened. Such a saddle-shaped bearing box is placed so as to cover the upper half of the outer ring 4 in an assembled state.

[0005] Of the double row tapered roller bearing 3 as described above,
The outer race 4 is internally fitted and held in the bearing housing 2. In the illustrated example, a step 10 is formed near the outer end (the left end in FIG. 12) of the inner peripheral surface of the bearing housing 2, and is fitted inside the inner end (the right end in FIG. 12) of the bearing housing 2. The outer race 4 is sandwiched between both sides of the outer race 4 with a fixed retaining ring (not shown). On the other hand, each of the inner races 5 has one end of the axle 1 (FIG. 12) in a state where the spacer 11 is sandwiched between the two inner races 5.
(Left end) is fitted outside. An annular member 12 called an oil drain is externally fitted to a portion of the end of the axle 1 that protrudes from the inner ring 5 on the outside in the axial direction. Further, the inner end surface of the inner inner ring abuts a step surface formed in the intermediate portion of the axle 1 via another annular member. Therefore, the pair of inner rings 5 is not displaced closer to the center of the axle 1 (rightward in FIG. 12) than in the state of FIG. And
The annular member 12 is pressed toward the outer end surface of the outer inner ring 5 by a nut 14 screwed into a male screw portion 13 formed at the outer end of the axle 1. Furthermore, the nut 1
4 is fixed to the outer end face of the axle 1 by bolts 15 and 15 and is provided on the inner circumference of the detent ring 16 with the groove provided on the outer circumference of the outer end of the axle 1 to engage the nut 14.
To prevent loosening.

On the other hand, at both ends of the outer ring 4, a seal case 17 formed by forming a metal plate such as a mild steel plate into a generally cylindrical shape with a crank-shaped cross section is fixedly fitted. The plurality of tapered rollers 6, 6 were installed by providing seal rings 18 as sealing means between the inner peripheral surfaces of both seal cases 17 and the outer peripheral surfaces of the annular members 12, respectively. The openings at both ends of the space are closed. With this configuration, the inside and outside of this space are shut off, and the lubricating grease sealed in this space is prevented from leaking to the outside, and foreign matters such as rainwater and dust enter the above space from outside. Has been prevented.

On one end surface of the axle 1, an encoder 19 formed of a magnetic metal material such as steel and having an L-shaped cross section in a ring shape as a whole is connected to the axle 1 by a plurality of bolts 20 and 20. Concentrically fixed. Concave portions and convex portions are formed alternately and at regular intervals in the circumferential direction on the outer peripheral edge of the outward flange-shaped annular portion 21 provided on the encoder 19, and the magnetic characteristics of the outer peripheral portion are circular. They are changed alternately and at equal intervals in the circumferential direction.

The one end opening of the bearing housing 2 is closed by a cover 22 fixed to one end of the bearing housing 2.
The cover 22 is formed entirely of a synthetic resin or metal material into a cylindrical shape with a bottom, and has a cylindrical portion 23 and a bottom plate portion 24 that closes an opening of one end (the left end in FIG. 12) of the cylindrical portion 23.
And an outward flange-shaped mounting portion 25 provided on the outer peripheral surface of the cylindrical portion 23 near the other end (the right end in FIG. 12). Such a cover 22 fits the other end of the cylindrical portion 23 inside one end of the bearing housing 2 and the mounting portion 2.
The mounting portion 25 is fixed to one end surface of the bearing box 2 with bolts in a state where the end portion 5 abuts on one end surface of the bearing box 2, thereby closing the one end opening of the bearing box 2.

A sensor diametrically penetrating both the inner and outer peripheral surfaces of the cylindrical portion 23 at a portion of the cylindrical portion 23 which is diametrically opposed to the outer peripheral edge of the annular portion 21 of the encoder 19. A mounting hole 26 is formed. Then, a rotation detecting sensor 27 is inserted into the sensor mounting hole 26, and a detecting portion provided on a front end surface (a lower end surface in FIG. 12) of the rotation detecting sensor 27 is provided on an outer peripheral edge of the ring portion 21. The detection unit is opposed to the detection unit via a minute gap. On the other hand, a sensor mounting concave hole 28 is formed in a portion located around the outer ring 4 in an intermediate portion of the bearing housing 2. The temperature sensor 29 is inserted into the sensor mounting recess 28.
Is installed.

In the case of the rotation supporting device with a sensor having the above-described configuration, when the encoder 19 rotates together with the axle 1 supporting and fixing the wheels during operation, the concave portion and the convex portion constituting the detected portion of the encoder 19 are formed. The rotation detection sensor 27
Pass alternately in the vicinity of the detection unit provided on the tip end surface of. As a result, the density of the magnetic flux flowing in the rotation detection sensor 27 changes, and the output of the rotation detection sensor 27 changes. The frequency at which the output of the rotation detection sensor 27 changes in this manner is proportional to the rotation speed of the wheel. Therefore, if the output of the rotation detection sensor 27 is sent to a controller (not shown), the rotation speed of the wheels can be detected, and the sliding control of the railway vehicle can be appropriately performed.

If the rotational resistance of the double-row tapered roller bearing 3 abnormally rises for some reason, such as excessive skew of the tapered rollers 6, 6 and the temperature of the double-row tapered roller 3 rises, The temperature sensor 29 detects this temperature. The temperature signal detected by the temperature sensor 29 in this manner is also sent to a controller (not shown), and the controller issues an alarm such as turning on a warning lamp installed in the driver's seat. When such an alarm is issued, the driver takes measures such as an emergency stop.

Further, although not shown in the drawings,
No. 43723 discloses an attachment hole provided in a cylindrical portion of a seal case in which a base end portion is internally fixed to an end portion of an outer ring, and various sensors such as a rotation detection sensor, a temperature sensor, and a vibration sensor are provided in the attachment hole portion. A structure for attaching the device is described. In the case of the structure described in this publication, the encoder for detecting the rotational speed is installed on the outer peripheral surface of the rotating shaft at a portion between the seal ring provided at the end of the seal case and the end surface of the inner ring. In order to support and fix the sensor to the seal case, an annular holding band-shaped member may be held on the outer peripheral surface of the seal case, or a partially annular member may be fitted around the seal case. I have to.

[0013]

In the case of the conventional structure shown in FIGS. 12 and 13, the rotation detection sensor 27 and the temperature sensor 2
9 is supported and fixed to the cover 22 or the bearing box 2 independently of each other, so that the mounting work of each of the sensors 27 and 29 is not only troublesome, but also the signal extraction from each of the sensors 27 and 29 is performed. It becomes troublesome. That is, the rotation detecting sensor 27 is fixed to the cover 22 by a plurality of bolts 31a, 31a through which the mounting flange 30a is inserted, and a signal is taken out by a harness 32a. The mounting flange 30b is fixed to the bearing housing 2 by a plurality of bolts 31b, 31b inserted therethrough, and a signal is taken out by a harness 32b.

For this reason, the mounting space for the sensors 27 and 29 is increased, the mounting work is complicated, and the handling of the harnesses 32a and 32b is also troublesome. On the other hand, in a rolling support device for a railway vehicle, the number of sensors incorporated in the rotating support device tends to increase, and in that case, the above-described problem becomes more remarkable.

On the other hand, Japanese Patent Application Laid-Open No. 2000-43723
In the case of the structure described in the above publication, in order to support the sensor on the seal case, an annular holding band-shaped member is held on the outer peripheral surface of the seal case, or Since a structure that fits outside the seal case is employed, a considerable part of the outer peripheral surface of the seal case is covered by the supporting member. For this reason, there is a possibility that heat from the seal case may not always be sufficiently released, which is not preferable from the viewpoint of ensuring the durability of the rolling bearing unit.
The rolling bearing unit with a rotation detecting device of the present invention has been invented in view of such circumstances.

[0016]

A rolling bearing unit with a rotation detecting device according to the present invention is provided at least with the rolling bearing unit, similarly to the above-mentioned conventionally known rolling bearing unit with a rotation detecting device. And a rotation detecting device for detecting the rotation state of the motor.
The rolling bearing unit includes a stationary wheel, a rotating wheel concentrically arranged with the stationary wheel, and a stationary-side and rotating-side orbit formed on peripheral surfaces of the stationary wheel and the rotating wheel facing each other. A plurality of rolling elements provided therebetween, a cylindrical seal case supported by the stationary wheel, and a circumferential surface of the seal case and a circumferential surface of a portion that rotates with the rotating wheel. And sealing means. Further, the rotation detecting device includes an encoder supported concentrically with the rotating wheel at a portion rotating with the rotating wheel, and a rotation detecting sensor supported at a non-rotating portion and having a detecting unit opposed to the encoder. It is provided with.

In particular, in the rolling bearing unit with a rotation detecting device according to the present invention, the encoder is provided in a portion whose periphery is covered by the seal case. or,
A sensor unit including a sensor holder holding the rotation detection sensor is supported on an outer peripheral surface of the seal case. A through hole is formed in a part of the seal case covered by the sensor unit. A part of the sensor unit, in which the detection unit of the rotation detection sensor is provided, is inserted into the seal case through the through hole, and the sensor unit is attached to the seal case relative to the sensor unit. Is fixed by connecting the mounting flange portion fixed to the outer peripheral surface of the seal case to a portion near the through hole.

[0018]

In the case of the rolling bearing unit with the rotation detecting device of the present invention configured as described above, the sensor unit holding the rotation detecting sensor is supported on the outer peripheral surface of the seal case. The support operation and the installation operation of the harness for extracting the signal of the rotation detection sensor can be easily performed. Therefore, the mounting space for the rotation detection sensor does not increase, and the mounting operation is not troublesome. Further, as the sensor unit is supported on the outer peripheral surface of the seal case, the area in which the sensor unit covers the outer peripheral surface of the seal case is extremely limited. For this reason, not only the material for forming the sensor unit can be reduced to reduce the cost, but also the heat radiation through the outer peripheral surface of the seal case can be improved, and the temperature rise inside the rolling bearing unit can be suppressed. .

[0019]

1 to 5 show a first embodiment of the present invention corresponding to claims 1 and 2. FIG. still,
This embodiment is characterized in that a rotation detecting sensor 27a for detecting the rotational speed of the axle 1 as a rotating shaft and a double-row tapered roller bearing as a rolling bearing unit that rotatably supports the axle 1. And a vibration sensor 33 such as an acceleration sensor for detecting the vibration of the double-row tapered roller bearing 3 is supported and fixed to the seal case 17a via the sensor unit 43. By doing so, the problem of the conventional structure described above is solved. Hereinafter, the configuration of the rolling bearing unit with the rotation detecting device of the present invention including such a characteristic portion will be described.

An axle 1, which rotates during use with wheels (not shown) supported and fixed, is mounted on the underside of a bearing box 2a, which is provided on a chassis of a railway vehicle and does not rotate during use, as a double row tapered roller bearing as a rolling bearing. 3, it is rotatably supported. In the case of this example, a saddle-shaped one is used as the bearing housing 2a. Therefore, the bearing housing 2a is mounted on the upper half of the outer race 4 constituting the double-row tapered roller bearing 3. The double-row tapered roller bearing 3 is arranged concentrically with the outer ring 4 which is a stationary wheel and a pair of inner rings 5a and 5b which are also rotating wheels, and a plurality of which are each a rolling element. And a plurality of tapered rollers 6. Outer ring 4 is made entirely cylindrical.
On the inner peripheral surface, there are multiple rows of outer raceways 7, 7 which are stationary raceways. Each of these outer raceways 7, 7 has a conical concave shape, and is inclined in such a direction that the inner diameter increases toward the axial end of the outer race 4.

The pair of inner races 5a and 5b are each formed in a substantially short cylindrical shape, and each of the outer races has a conical convex inner race raceway 8, 8 which is a rotating raceway described in the claims. Is formed. Each of the inner rings 5a and 5b is disposed concentrically with the outer ring 4 on the inner diameter side of the outer ring 4 in a state where the end faces on the small diameter side of the inner rings 5a and 5b abut each other via the inner ring spacer 35. Furthermore, each of the above tapered rollers 6, 6
Between the outer raceways 7, 7 and the inner raceways 8, a plurality of the respective raceways are rotatably provided while being held by retainers 9, 9.

Among the double row tapered roller bearings 3 as described above,
The outer race 4 is held below the bearing housing 2a. Since the weight of the railcar is added to the contact surface between the outer peripheral surface of the upper half portion of the outer ring 4 and the inner peripheral surface (lower surface) of the bearing box 2a, the outer ring 4 does not fall off from the inside of the bearing box 2a. .
At the end of the axle 1, annular members 12a, 12a called oil cuts are respectively fitted at positions sandwiching the inner rings 5a, 5b from both sides in the axial direction. Further, the inner end surface of the inner inner ring 5a is connected to the stepped surface 3 formed in the intermediate portion of the axle 1 via the annular member 12a and another annular member 36.
7 is hit. Therefore, the pair of inner rings 5a, 5
b is not displaced closer to the center of the axle 1 (rightward in FIG. 1) than in the state of FIG.

On the other hand, the outer inner ring 5b and the annular member 12
a, the encoder 19a is sandwiched between the outer ring 5a and the annular member 12a.
It is suppressed by. The encoder 19a is formed of a magnetic metal plate such as a mild steel plate as a whole in the shape of a circular plate, and has a large number of projecting pieces each protruding outward in the radial direction as shown in FIG. 39, 39 are formed at equal intervals in the circumferential direction. Therefore, the encoder 19
The magnetic characteristics of the outer diameter side half portion of a vary alternately in the circumferential direction. A plurality of (three in the illustrated example) bolts 40, 40 are provided on the end surface of the axle 1.
And fixed by And these bolts 4
Based on the tightening of 0, 40, the front edge (right end in FIGS.
The annular member 12a and the encoder 19a are pressed toward the outer inner ring 5b while being held down at the edge of "a". In this state, the dimensions of each part are regulated so that the internal clearance of the double-row tapered roller bearing 3 has an appropriate value.
In this way, the encoder 19a can be fixed to the axle 1 by connecting the pressing end plate 38 to the end surface of the axle 1 with the bolts 40, 40. Therefore, the encoder 19a is connected to the axle 1 or the axle 1. A process such as press-fitting into the inner ring 5b is not required, and the cost can be reduced by reducing the number of assembly steps.

On the other hand, at both ends of the outer ring 4, base ends of seal cases 17a and 17b each formed by forming a metal plate such as a mild steel plate into a substantially cylindrical shape with a crank cross section are fixedly fitted. ing. And these two seal cases 17
a sealing ring 18, which is a sealing means, defined between an inner peripheral surface of a portion of the intermediate member a, 17b near the tip of the intermediate portion and an outer peripheral surface of the intermediate portion of each of the annular members 12a, 12b;
18, the plurality of tapered rollers 6, 6
Are closed at both ends of the space 41 in which is installed. With this configuration, the inside and outside of this space 41 are shut off, and this space 4
In addition to preventing the grease for lubrication sealed in 1 from leaking to the outside, it also prevents foreign substances such as rainwater and dust from entering the space 41 from outside. The coupling projections 42, 4 are provided at two positions on the outer peripheral surface of the seal case 17a.
The projection 2 prevents the seal case 17a from rotating with respect to the bearing housing 2a. That is, the rotation of the seal case 17a is prevented by the engagement between the engaging projections 42, 42 and the lower surfaces of both ends of the bearing box 2a.

Further, the pair of seal cases 17a, 17
b, the seal case 17a near the outer end of the axle 1
A through hole 44 through which a part of the sensor unit 43 is inserted is formed in a portion near the base end of the middle part. The sensor unit 43 has a sensor holder 46 held in a sensor case 45. The sensor holder 46 is made of a molding material such as epoxy resin, and is formed by projecting a column-shaped convex portion 48 at the center of the inner surface of a rectangular parallelepiped main portion 47. In such a sensor holder 46, the rotation detecting sensor 27a, the temperature sensor 29a, and the vibration sensor 33 are embedded and supported. The rotation detection sensor 27a is embedded and supported at the tip of the projection 48 with the detection unit positioned on the side surface of the projection 48.
On the other hand, the temperature sensor 29a is provided at the portion near the base of the intermediate portion of the projection 46 so as to efficiently detect the temperature of the seal case 17a.
Numerals 3 are embedded and supported in the main portion 47 so that the vibration of the seal case 17a can be efficiently detected.

On the other hand, each of the sensor cases 45 is made of a nonmagnetic metal material such as austenitic stainless steel or aluminum alloy (including die casting).
Alternatively, the main body 49 and the lid 50 made by shaving or the like are formed.
Consisting of The main body 49 includes a rectangular box-shaped storage portion 51 having an open outside, and a mounting flange portion 5 formed by extending a bottom plate portion 52 of the storage portion 51 in a circumferential direction.
3 and 53. The surface of the bottom plate portion 52 and the mounting flange portions 53, 53 facing the outer peripheral surface of the seal case 17a is an arc-shaped concave surface that is in close contact with the outer peripheral surface (having the same radius of curvature). Also, the bottom plate 52
A support cylinder 54 is formed at the center of the support cylinder 54, into which the projection 48 of the sensor holder 46 can be inserted. In a state where the sensor unit 43 is assembled, the convex portion 48 is fitted in the support tube portion 54 and the main portion 47 is fitted in the storage portion 51 without rattling. Further, the opening of the storage portion 51 is closed by the lid 50, and the lid 50 and the storage portion 51 are connected by screws, so that the sensor holder 46 is held and fixed in the sensor case 45.
When the sensor unit 43 is actually manufactured, the sensors 27a, 29a, and 33 are installed in the support tube portion 54 or the storage portion 51, and these support tube portions 54
Then, the molding material is filled in the storage section 51. Therefore, water does not adhere to the sensors 27a, 29a, and 33, and the temperature or vibration of the seal case 17a can be efficiently transmitted to the temperature sensor 29a or the vibration sensor 33.

The sensor unit 43 as described above is attached to the seal case 17a with respect to the mounting flanges 53, 5 and 5.
The seal case 17a is fixed between the anchor member 3 and the anchor member 55 by sandwiching the seal case 17a. This anchor member 55
Is formed in a circular arc shape by, for example, shaving a metal material.
A pair of screw holes 57, 57 are formed in the outer peripheral surfaces of both end portions, respectively, and a concave portion 56 into which the base 4 can be inserted is formed. The sensor unit 43 is connected to the seal case 17.
In order to fix the sensor unit 43 and the sensor unit 43, the sensor unit 43 and the anchor member 55 are opposed to each other via the seal case 17a, and the screws 58, 58 inserted through the mounting flanges 53, 53 and the seal case 17a are attached. It is screwed into each of the screw holes 57, 57 and further tightened.

As described above, if the screws 58, 58 are screwed and tightened while the seal case 17a is sandwiched between the sensor unit 43 and the anchor member 55, the seal case 17a is deformed. The sensor unit 43 can be supported and fixed to the seal case 17a without any problem. Further, since the strength itself of the seal case 17a is also improved, it can be implemented as a preferable structure. The anchor member 55 can be fixed to the seal case 17a in advance before the sensor unit 43 is attached to the seal case 17a. For this reason, the sensor unit 43 is later attached to the seal case 17.
a, it is not necessary to transport the rolling bearing in a state where the sensor unit 43 is previously mounted on the rolling bearing such as the double-row tapered roller bearing 3 or the like. Handling becomes easy. Further, the repair / replacement work of the sensor unit 43 is also facilitated. The anchor member 55 includes a plurality of screws 5.
By being fixed to the seal case 17a by 8 and 58, and being in contact with the inner peripheral surface of the seal case 17a and the curved surfaces, the screws 58, 58 are effectively prevented from falling off due to loosening. Can be prevented.

A packing 61 is provided at a portion of the bottom plate 52 of the sensor case 45 surrounding the base end of the support cylinder 54, and the packing 61 is attached to the bottom plate 5.
By sandwiching the support cylinder 2 between the seal case 17a and the seal case 17a, the portion where the support cylinder 54 is inserted through the through hole 44 is kept waterproof. Also, the seal case 17a
A heat conductive paste is applied to a contact portion between the outer peripheral surface of the sensor case 45 and the inner side surface of the sensor case 45 as necessary, so that heat can be transmitted well from the seal case 17a to the sensor case 45. To

With the sensor unit 43 supported and fixed to the seal case 17a as described above, the detection unit of the rotation detection sensor 27a
9a is opposed to a half of the outer surface of one side closer to the outer diameter (the lower half of the left side in FIGS. 1 and 3) via a minute gap in the axial direction.
The temperature sensor 29a is located inside a through hole 44 formed in the sensor case 45, and the vibration sensor 33 is located radially outside the sensor case 45. A harness for extracting output signals of these sensors 27a, 29a, and 33 and sending them to a controller (not shown) is provided in a single cable 59 in a state where the cover 5
It is derived from the coupling cylinder 60 provided at 0. In the present example, the detection unit of the rotation detection sensor 27a is opposed to a half of the outer diameter of one side of the encoder 19a, but this detection unit is opposed to the outer peripheral edge of the encoder 19a. It can also be configured.

In the case of the rotation supporting device with the rotation detecting device of the present embodiment constructed as described above, when the encoder 19a rotates together with the axle 1 supporting and fixing the wheels during operation, a large number of encoders formed on the outer peripheral edge of the encoder 19a are formed. The protruding pieces 39, 39 and the notch-shaped portion existing between the circumferentially adjacent protruding pieces 39, 39 alternately pass near the detection unit of the rotation detection sensor 27a. As a result, the density of the magnetic flux flowing in the rotation detection sensor 27a changes, and the output of the rotation detection sensor 27a changes. The frequency at which the output of the rotation detection sensor 27a changes in this manner is proportional to the rotation speed of the wheel. Therefore, the rotation detection sensor 27
If the output of a is sent to a controller (not shown), the rotation speed of the wheels can be detected, and the sliding control of the railway vehicle can be appropriately performed.

When the rotational resistance of the double-row tapered roller bearing 3 abnormally rises for some reason, such as excessive skew of the tapered rollers 6, 6, and the temperature of the double-row tapered roller 3 rises, The temperature sensor 29a detects this temperature. The outer race 4 and the inner races 5a, 5b constituting the double row tapered roller bearing 3 and the outer raceways 7, 7 and the inner raceways 8, 8 or the rolling surfaces of the respective tapered rollers 6, 6 may be damaged, such as peeling. Is generated, and as a result, when the vibration generated in the double-row tapered roller bearing 3 portion with the rotation of the axle 1 increases, the vibration sensor 33 detects the vibration. The signal indicating the temperature detected by the temperature sensor 29a or the signal indicating the vibration detected by the vibration sensor 33 is also sent to a controller (not shown), and the controller outputs a warning signal provided at the driver's seat. An alarm such as turning on a light is issued.
When such an alarm is issued, the driver takes measures such as an emergency stop.

In the case of the rolling bearing unit with a rotation detecting device of the present invention, the rotation detecting sensor 27a and the temperature sensor 29a are provided on the outer peripheral surface of the seal case 17a.
And the vibration sensor 33, and supports the sensor unit 43.
a, The support work of 33 can be easily performed. In addition, since the harnesses for extracting the signals of the sensors 27a, 29a, and 33 are combined in one cable 59, the work of installing these harnesses can be performed easily. Therefore, the mounting space for the sensors 27a, 29a, and 33 does not increase, and the mounting operation does not become troublesome.

The sensor unit 43 is attached to the outer peripheral surface of the seal case 17a by the mounting flange portion 5.
3, 53 and the anchor member 55 are connected and fixed. The circumferential length of the sensor case 45 including each of the mounting flange portions 53 is the same as that of the seal case 1.
7a is sufficiently shorter than the circumferential length of 7a (about 1/4 circumference in the illustrated example). Accordingly, with the support of the sensor unit 43 on the outer peripheral surface of the seal case 17a, the sensor unit 43
The area that covers the outer peripheral surface of the slab is extremely limited. For this reason, the sensor unit 4 including the sensor case 45
In addition to reducing the cost by reducing the number of materials for composing 3, the exposed area of the outer peripheral surface of the seal case 17a is sufficiently ensured to improve heat dissipation through the outer peripheral surface, and the double-row cone is formed. The temperature rise inside the roller bearing 3 can be suppressed. Further, since the encoder 19a is provided axially inside the seal ring 18 serving as a sealing means, foreign matter hardly enters the encoder 19a portion, and the foreign matter hardens due to the foreign matter.
Can be prevented from being damaged.

The structure and basic operation of the rolling bearing unit with a rotation detecting device of the present embodiment are as described above. By combining such a rolling bearing unit with a rotation detecting device with a comparator and a threshold value setting circuit, Abnormality detection of the double-row tapered roller bearing 3, in which the operating speed frequently changes from a low speed to a high speed, can be performed with high reliability. That is, in the case of a rolling bearing unit whose rotation speed changes frequently from a high speed to a low speed, such as a double-row tapered roller bearing 3 for supporting the axle 1 of a railway vehicle, it is determined whether there is an abnormality according to the rotation speed. Changing the threshold value for determination is preferable for performing highly reliable determination. The reason for this is that if a fixed threshold value is used, it must be based on the high-speed rotation at which the temperature rise and vibration are most remarkable, and it becomes difficult to detect the abnormality that occurred during the low-speed operation. Next, four examples of a judgment circuit for judging the presence or absence of abnormality detection in consideration of such circumstances will be described.

First, in the first example shown in FIG. 6, the rotation speed of the axle 1 supported by the double-row tapered roller bearing 3 and the temperature sensor 2 obtained by the detection signal of the rotation detection sensor 27a are shown.
The presence or absence of an abnormality in the double-row tapered roller bearing 3 is determined based on the temperature of the double-row tapered roller bearing 3 obtained from the detection signal 9a. In the first example, a threshold value setting circuit 63 uses a speed signal representing a value related to the rotation speed of the axle 1 obtained by a rotation speed detection circuit 62 that processes a detection signal of the rotation detection sensor 27a to detect an abnormality. Determine the threshold. The threshold value and the temperature signal sent from the temperature sensor 29a are compared by a comparator 64, and a signal representing the result of the comparison is judged by a bearing abnormality judgment circuit 65, and the double row tapered roller bearing 3 is judged. The presence or absence of abnormality is determined. When there is an abnormality, a signal is sent to an alarm device 66 such as a buzzer or a warning light,
The alarm 66 is activated to issue an alarm notifying the driver or worker of the occurrence of an abnormality. In the abnormality detection device of this embodiment, the temperature threshold for abnormality detection is sequentially changed in accordance with a change in the rotation speed of the double-row tapered roller bearing 3 obtained from the detection signal of the rotation detection sensor 27a. In addition, it is possible to detect an abnormality of the rolling bearing unit that occurs not only at the time of high-speed rotation but also at the time of low-speed rotation.
It is inevitable that a certain time delay occurs after the temperature of the double-row tapered roller bearing 3 actually changes and before the detection value of the temperature sensor 29a changes. Therefore, if such a time delay is determined in advance by an experiment, and a correction term based on the experimental result is installed in the bearing abnormality determination circuit 65, more reliable determination can be performed. .

Next, the second example shown in FIG. 7 shows the rotational speed of the axle 1 supported by the double-row tapered roller bearing 3 and the vibration sensor 3 obtained by the detection signal of the rotation detecting sensor 27a.
Double-row tapered roller bearing 3 obtained by the detection signal
The presence or absence of an abnormality in the double-row tapered roller bearing 3 is determined from the above vibration. In the case of this example, a threshold for detecting an abnormality related to the vibration is set in accordance with a speed signal obtained based on a detection signal of the rotation detection sensor 27a,
The threshold value and a signal from the vibration sensor 33 are compared by a comparator 64a to determine whether the double-row tapered roller bearing 3 is abnormal. In the case of such an abnormality detection device of the present example, the threshold value for abnormality detection relating to the vibration is sequentially changed in accordance with a change in the rotation speed of the double-row tapered roller bearing 3, so that the above-described operation at a low speed rotation is performed. It is possible to detect abnormal vibration of the double-row tapered roller bearing 3, and it is possible to detect even a slight peeling generated on the rolling contact surface inside the double-row tapered roller bearing 3 at an early stage.

That is, in general, the magnitude of the vibration generated during the operation of the rolling bearing unit including the double-row tapered roller bearing 3 increases as the rotation speed increases. For this reason, when it is attempted to determine whether or not there is an abnormality in the rolling bearing unit such as the double-row tapered roller bearing 3 based on only the detection signal of the vibration sensor 33, the vibration value generated at the expected maximum rotational speed is adjusted. It is necessary to set a threshold value for abnormality detection. For this reason, it was difficult to detect the abnormality of the rolling bearing unit such as the double-row tapered roller bearing 3 at the time of low-speed rotation. On the other hand, if the processing apparatus of this example is used, the threshold value for abnormality detection can be sequentially changed in accordance with the rotation speed at that time, so that abnormality detection such as peeling can be increased based on the magnitude of vibration. Can be done with reliability. In addition, when this example is applied to the abnormality determination of the rolling bearing unit for a railway vehicle, the vibration when passing through the joint of the rail is excluded from the determination target in consideration of the rail length and the rotation speed.

Next, in the fourth example shown in FIG. 8, the rotation speed of the axle 1 supported by the double-row tapered roller bearing 3 and the vibration sensor 3 obtained by the detection signal of the rotation detection sensor 27a are also shown.
Double-row tapered roller bearing 3 obtained by the detection signal
The presence or absence of an abnormality in the double-row tapered roller bearing 3 is determined from the above vibration. Particularly, in the case of this example, the waveform of the vibration detected by the vibration sensor
After the analysis at step 7, it is determined whether or not the double-row tapered roller bearing 3 is abnormal. For this reason, in the case of this example, the rotation detection sensor 27a
Double-row tapered roller bearing 3 obtained from the detection signal of
Cycles T ₁ , T 2 of various vibrations generated from the double-row tapered roller bearing 3 based on a rotation speed signal indicating the rotation speed of
_2, the calculation of T _3, and subjected to the determination of the presence or absence of abnormality of the double row tapered roller bearing 3.

Each of these periods T ₁ , T ₂ , T ₃ is
In the case where the double-row tapered roller bearing 3 rotates in the inner ring, T ₁ indicates the cycle of vibration when the outer ring raceway 7 formed on the inner peripheral surface of the outer ring 4 is separated, and T ₂ indicates the outer peripheral surface of the inner ring 5. The cycle of the vibration when the inner ring raceway 8 formed at the time of separation occurs is represented by T ₃
Represents the cycle of vibration when the rolling surfaces of the tapered rollers 6, 6, which are rolling elements, are separated. By analyzing the period of the signal from the vibration sensor 33 using the rotation speed signal, it is possible to determine only whether or not the double-row tapered roller bearing 3 has been damaged due to peeling. Instead, it is also possible to specify which portion of the double-row tapered roller bearing 3 has peeled off.

For example, when the outer raceway 7 formed on the inner peripheral surface of the outer race 4 on the stationary side in the double-row tapered roller bearing 3 used for rotation of the inner race is peeled off, the following formula is used. Oscillation of frequency occurs. f ₁ = z · fc where z is the number of rolling elements, fc is the rotation frequency of the cage, and the cycle T _{1 of} this vibration is expressed by the following equation. T ₁ = 1 / f ₁ = 1 / z · fc On the other hand, when peeling occurs on the inner raceway 8 formed on the outer peripheral surface of the inner race 5 on the rotating side, it is expressed by the following equation. Oscillation of frequency occurs. f ₂ = z · (fr−fc) where z: the number of rolling elements, fr: inner ring rotation frequency, fc: cage rotation frequency, and the cycle T ₂ of the vibration is represented by the following equation. T ₂ = 1 / f ₂ = 1 / {z · (fr−fc)} Further, when peeling occurs on the rolling surfaces of the tapered rollers 6, 6 which are the rolling elements, the following expression is used. Oscillation of frequency occurs. f ₃ = 2 · fb where fb is the rotation frequency of the rolling element. The cycle T _{3 of} this vibration is expressed by the following equation. T ₃ = 1 / f ₃ = 1/2 · fb The frequencies of the above fc, fr, fb, etc. can be calculated by knowing the specifications of the double-row tapered roller bearing 3 and the number of revolutions thereof. By analyzing the above, it is possible to identify at which part of the double-row tapered roller bearing 3 the separation has occurred.

For example, when the vibration component having a period other than the above-described periods T ₁ , T ₂ , and T ₃ is increasing, an abnormality occurs in a portion other than the rolling contact surface of the double-row tapered roller bearing 3. Will be. Therefore, when the period analysis of the detection signal of the vibration sensor 33 is performed by the period analysis circuit 67 as in the present embodiment, the rotation supporting portion and its peripheral portion including the double-row tapered roller bearing 3 and its peripheral portion are included. It is possible to detect the abnormality of the part including. In this case, for example, when the vibration corresponding to the primary component of the rotational speed is particularly large, it is estimated that uneven wear due to sliding has occurred at one portion of the wheel.

Next, in the fourth example shown in FIG. 9, the rotation speed of the axle 1 supported by the double-row tapered roller bearing 3 and the vibration sensor 3 obtained by the detection signal of the rotation detection sensor 27a are also shown.
Double-row tapered roller bearing 3 obtained by the detection signal
The presence or absence of an abnormality in the double-row tapered roller bearing 3 is determined from the above vibration. In particular, in the case of this example, the signal representing the vibration is passed through an envelope processing circuit 68 for performing envelope processing, and the frequency analysis is performed using the waveform after the envelope processing. As in the third example shown in FIG. 8, if the frequency of the vibration waveform itself (raw waveform) detected by the vibration sensor 33 is subjected to frequency analysis as it is, it is impossible to analyze the abnormality of the bearing.
When the raw waveform of this vibration is subjected to envelope processing and the frequency analysis circuit 69 performs frequency analysis using the processed waveform,
It is possible to analyze the abnormality of the rolling bearing unit such as the double row tapered roller bearing 3 and the like. Then, the frequencies f ₁ , f ₂ , f _{3 of the} vibration generated based on the separation of the rolling contact portion
Can be detected.

In any case, the abnormality detecting apparatus shown in FIGS. 6 to 9 shows four examples, and the setting of the threshold value for detecting the abnormality of the rolling bearing unit such as the double row tapered roller bearing 3 is performed by changing the rotation speed. By successively changing and analyzing the values, it is possible to set an optimum threshold value according to the state of the rolling bearing unit such as the double-row tapered roller bearing 3 which changes every moment, which was difficult in the past. Further, the accuracy of determining whether or not there is an abnormality in the rolling bearing unit such as the double-row tapered roller bearing 3 can be drastically improved. Each of the circuits shown in FIGS. 6 to 9 can be processed by software using a microcomputer or a DSP (digital signal processor).

In a configuration in which a vibration sensor and a temperature sensor are combined in addition to the rotation detection sensor, the abnormality of the double-row tapered roller bearing 3 can be detected from both the vibration and temperature signals. It is possible to detect a wide range of abnormalities such as poor lubrication due to deterioration of the rolling contact surface and damage to the rolling contact surface due to foreign matter being caught. According to the abnormality detecting device for the double-row tapered roller bearing 3 as described above, it is possible to detect an abnormality of the rolling bearing unit of the double-row tapered roller bearing 3 and the like at an early stage. It is possible to effectively prevent serious damage such as seizure from occurring in the rolling bearing unit such as the bearing 3.

Next, FIGS. 10 to 11 show a second embodiment of the present invention corresponding to claims 1 to 3. FIG. In the case of the present example, a through hole 44 formed in the seal case 17a corresponding to the mounting position of the sensor unit 43a is formed with the shaft of the seal case 17a sandwiching the seal ring 18 as the sealing means described in the claims. In the direction, it is on the opposite side to the portion where the tapered rollers 6, 6 are installed. That is, in the case of the present example, the seal ring 18 is provided between the inner peripheral surface of the proximal portion of the seal case 17a near the intermediate portion and the outer peripheral surface of the proximal portion of the annular member 12b. .
An encoder 19b is externally fitted and fixed to a portion of the annular member 12b near the tip. This encoder 19b
A magnetic metal such as steel is formed in an external gear shape, and a large number of convex portions are present on the outer peripheral surface at equal intervals in the circumferential direction. Therefore, the magnetic properties of the outer peripheral surface of the encoder 19b change alternately and at equal intervals in the circumferential direction.

On the other hand, the sensor holder 46a constituting the sensor unit 43a is formed by protruding a convex portion 48a at one axial end of the central portion of the main portion 47a in the circumferential direction. The rotation detecting sensor 27a is attached to the tip of the convex portion 48a.
The temperature sensor 29a and the vibration sensor 33 are embedded and supported in a part of the main part 47a which is outside the convex part 48a.

The above-described sensor unit 43a which is formed by holding such a sensor holder 46a in a sensor case 45a.
Is the mounting flange 5 provided on the sensor case 45a.
A part of the seal case 17a is sandwiched between the pair of anchor members 3, 53 and a pair of anchor members 55a, 55a arranged on the inner diameter side of the seal case 17a, so that the seal case 17a is fixedly connected to the seal case 17a. . That is, the screws 58, 58 inserted through the mounting flanges 53, 53 are screw holes 57, 57 formed in the anchor members 55 a, 55 a.
The sensor unit 4
3a is fixedly connected to the seal case 17a.

In the case of this embodiment, a pair of two divided anchor members 55a, 55a is used.
a and 55a are discontinuous at the protruding portion 48a where the rotation detection sensor 27a is embedded. Therefore, the detection unit of the rotation detection sensor 27a is connected to each of the anchor members 55.
a, 55a, the encoder 19b
Can be closely opposed to the outer peripheral surface of the light emitting element. On the other hand, the temperature sensor 29a and the vibration sensor 33 are closely opposed to the outer peripheral surface of the seal case 17a via the metal sensor case 45a, so that the temperature and the vibration of the seal case 17a can be detected.

In the case of the present embodiment constructed as described above, a seal ring as a sealing means is provided between the through hole 44 for installing the sensor unit 43a and the portion where the tapered rollers 6, 6 are installed. Because of the presence of the foreign matter 18, even if foreign matter enters the inside of the seal case 17a through the through hole 44 due to the attachment / detachment work of the sensor unit 43a or the like, the foreign matter reaches the portion where the tapered rollers 6, 6 are installed. There is no intrusion. For this reason, the rolling contact surfaces of these tapered rollers 6, 6 and the outer raceways 7, 7 and the inner raceways 8, 8 are prevented from being damaged by foreign matter, and the double row tapered roller bearings are prevented. 3 can be improved in durability. Other configurations and operations are the same as those of the first example described above, and thus, duplicate description will be omitted.

In each of the embodiments, the sealing means is not limited to the contact type seal ring 18 as shown in the figure, but may be a non-contact type sealing means such as a labyrinth seal. Further, the structure of the rolling bearing unit is not limited to the double-row tapered roller bearing unit as shown in the figure, but may be a ball bearing, a cylindrical roller bearing, a single-row rolling bearing, or the like. Further, the encoder constituting the rotation detecting device is not limited to the encoder made of a magnetic metal, but may be an encoder made of a multi-pole magnet in which S poles and N poles are alternately arranged in the circumferential direction.

[0052]

Since the rolling bearing unit with the rotation detecting device of the present invention is constructed and operates as described above, not only can the mounting space for the sensors such as the rotation detecting sensor be reduced, but also the mounting work becomes easy. In addition, it is easy to handle a harness for extracting signals from these sensors. For this reason, it is possible to reduce the size and cost of the rotary support portions of various mechanical devices, such as the rotary support portion of the axle of the railway vehicle, and to improve the design flexibility. In addition, the temperature rise of the rolling bearing unit is suppressed, and the durability of the rolling bearing unit can be ensured.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first example of an embodiment of the present invention.

FIG. 2 is a view seen from the left side of FIG. 1;

FIG. 3 is an enlarged view of the lower left part of FIG. 1;

FIG. 4 is a sectional view taken along line AA of FIG. 1;

FIG. 5 is a view of an encoder taken out and a half thereof viewed from the same direction as in FIG. 4;

FIG. 6 is a block diagram showing a first example of a circuit for detecting an abnormality of the rolling bearing unit.

FIG. 7 is a block diagram showing the second example.

FIG. 8 is a block diagram showing a third example.

FIG. 9 is a block diagram showing a fourth example.

FIG. 10 is a view similar to FIG. 1, showing a second example of the embodiment of the present invention.

FIG. 11 is a sectional view taken along line BB of FIG. 10;

12 shows an example of a conventional structure, COD of FIG.
Sectional view.

FIG. 13 is a half end view as viewed from the left side of FIG. 12;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Axle 2, 2a Bearing box 3 Double row tapered roller bearing 4 Outer ring 5, 5a, 5b Inner ring 6 Tapered roller 7 Outer ring raceway 8 Inner ring raceway 9 Cage 10 Step 11 Spacer 12, 12a, 12b Ring member 13 Male screw part 14 Nut 15 Bolt 16 Detent ring 17, 17a, 17b Seal case 18 Seal ring 19, 19a, 19b Encoder 20 Bolt 21 Ring part 22, 22a, 22b Cover 23, 23a, 23b Cylindrical part 24, 24a Bottom plate part 25 Mounting part 26 Sensor mounting hole 27, 27a Rotation detecting sensor 28 Sensor mounting concave hole 29, 29a Temperature sensor 30a, 30b Mounting flange 31a, 31b Bolt 32a, 32b Harness 33 Vibration sensor 35 Inner ring spacer 36 Ring member 37 Step surface 38 Suppression end Plate 39 protruding piece 40 bolt 41 Space 42 Engagement convex part 43, 43a Sensor unit 44 Through hole 45, 45a Sensor case 46, 46a Sensor holder 47, 47a Main part 48, 48a Convex part 49 Main body 50 Lid body 51 Storage part 52 Bottom plate part 53 Mounting flange part 54 Supporting tube part 55, 55a Anchor member 56 Depression 57 Screw hole 58 Screw 59 Cable 60 Coupling tube part 61 Packing 62 Rotational speed detection circuit 63 Threshold setting circuit 64, 64a Comparator 65, 65a Bearing abnormality determination circuit 66 Alarm 67 Period analysis circuit 68 Envelope processing circuit 69 Frequency analysis circuit

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G01P 3/488 G01P 3/488 L (72) Inventor Shigeru Endo 1-5-150 Kugenuma Jinmei 1-chome Kugenuma, Fujisawa City, Kanagawa Prefecture No. Nippon Seiko Co., Ltd. (72) Inventor Toshio Takahashi 1-5-150 Kugenuma Shinmei, Fujisawa-shi, Kanagawa F-term (reference) 3J016 AA04 BB03 BB17 CA03 3J101 AA16 AA25 AA32 AA43 AA54 AA62 BA73 FA22 FA23 FA24 GA01 GA02 GA36

Claims (3)

[Claims] 1. A rolling bearing unit comprising at least a rotation detecting device for detecting a rotation state of the rolling bearing unit, wherein the rolling bearing unit is disposed concentrically with the stationary wheel and the stationary wheel. And a plurality of rolling elements provided between a stationary-side orbit and a rotating-side orbit formed on peripheral surfaces of the stationary wheel and the rotating wheel facing each other, and supported by the stationary wheel. A cylindrical seal case, and sealing means provided between a peripheral surface of the seal case and a peripheral surface of a portion that rotates together with the rotary wheel. A rotation detecting device comprising: an encoder supported concentrically with the rotating wheel at a portion that rotates together with the rotating wheel; and a rotation detecting sensor supported at a non-rotating portion and having a detection unit opposed to the encoder. A rolling bearing unit,
The encoder is provided at a portion whose periphery is covered by the seal case. A sensor unit including a sensor holder holding the rotation detection sensor is supported on an outer peripheral surface of the seal case. A portion of the sensor unit covered by the sensor unit is formed with a through hole, and a portion of the sensor unit where the detection unit of the rotation detection sensor is provided is inserted into the seal case through the through hole. The sensor unit is fixed to the seal case by connecting a mounting flange fixed to the sensor unit to a portion near the through hole on an outer peripheral surface of the seal case. Rolling bearing unit with rotation detection device. 2. The rolling bearing unit with a rotation detecting device according to claim 1, wherein at least one type of sensor selected from a temperature sensor and a vibration sensor is held in the sensor holder in addition to the rotation detecting sensor. . 3. The rotation detecting device according to claim 1, wherein the through hole is located on a side opposite to a portion where the rolling element is disposed with respect to an axial direction of the seal case with the sealing means interposed therebetween. Rolling bearing unit.