JP2002295496A - Rolling bearing unit with sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a structure capable of detecting a temperature of a double row tapered roller bearing unit 3 with high precision at low cost. SOLUTION: A terminal part of a seal case 15a made of a metallic plate is internally fitted into an end part of an outer ring 4 by tightening and fitting it. A temperature sensor 23a is connected and is fixed to an outer face of a circular ring part 25 formed in a tip part of the seal case 15a. A detection signal of this temperature sensor 23a is sent to a control device through a harness 24a, a relay connector 26 supported on a cover 18 by passing through it, and a cord 27. Since it is possible to let a temperature of the seal case 15a agree with a temperature of the outer ring 4 substantially, accuracy of temperature detection can be improved. Moreover, cost can be reduced because troublesome machining for mounting the temperature sensor 23a is not required.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION A rolling bearing unit with a sensor according to the present invention is used for fixing a rotating shaft of wheels of a railway vehicle or a rotating shaft of various industrial machinery such as a rolling mill to a fixed portion such as a vehicle body or a support base. And is used to detect an abnormality of the rolling bearing unit at an early stage.

[0002]

2. Description of the Related Art For example, a rolling bearing unit is used to rotatably support a wheel of a railway vehicle with respect to a bearing box fixed to the railway vehicle. Further, in order to detect an abnormality occurring in the rolling bearing unit at an early stage, it is necessary to detect the temperature of the rolling bearing unit. Because of this,
A rolling bearing unit with a sensor, in which a temperature sensor is incorporated in the rolling bearing unit, rotatably supports the wheel with respect to the bearing box and detects the temperature of the rolling bearing unit.

FIG. 2 shows an example of such a conventional rolling bearing unit with a sensor for a railway vehicle. An axle 1, which is a rotating shaft that rotates during use with a wheel (not shown) supported and fixed, is rotatably provided by a double-row tapered roller bearing 3, which is a rolling bearing unit, on the inner diameter side of a bearing box 2 that does not rotate during use. I support it. The double-row tapered roller bearing 3 includes an outer ring 4 and a pair of inner rings 5a, 5b concentrically arranged with each other, and a plurality of tapered rollers 6, 6. Outer ring 4 is made entirely cylindrical.
The inner peripheral surface has multiple rows of outer raceways 7,7. Each of these outer raceways 7, 7 has a conical 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, 5b are each formed in a substantially short cylindrical shape, and conical inner raceways 8, 8 are formed on the respective outer peripheral surfaces. 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 with the end faces on the smaller diameter side facing each other. Further, each of the tapered rollers 6, 6 can be rolled freely between the outer raceways 7, 7 and the inner raceways 8, 8 while being held by a plurality of retainers 9, 9, respectively. Provided.

[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. On the other hand, each of the inner rings 5a, 5b is
The axle 1 is externally fitted to a portion closer to the outer end (the left end in FIG. 2) of the axle 1 with the spacer 10 held therebetween. A portion of the end of the axle 1 protruding beyond the inner ring 5a on the outside in the axial direction (left side in FIG. 2) is provided with an annular member 11a called an oil drain
Is fitted outside. Further, the inner end face of the inner ring 5b on the inner side (the right side in FIG. 2) abuts on a step surface 12 formed at the intermediate portion of the axle 1 via another annular member 11b. Therefore, the pair of inner rings 5a and 5b is not displaced closer to the center of the axle 1 (rightward in FIG. 2) than in the state of FIG. Then, an inner end edge of a round bowl-shaped end plate 14 (right end edge in FIG. 2) which is externally fitted to the outer end of the axle 1 and further fixed and fixed to the axle 1 by a plurality of bolts 13, 13. As a result, the annular member 11a is connected to the outer inner ring 5a.
To the outer end face of

On both ends of the outer ring 4, seal cases 15a and 15b, each of which is formed by forming a metal plate such as a mild steel plate into a generally cylindrical shape with a crank-shaped cross section, are fixedly fitted therein. Then, these two seal cases 15a, 15b
Seal rings 16a and 16b are provided between the inner peripheral surface of the inner ring member and the outer peripheral surface of each of the annular members 11a and 11b to open both ends of the internal space 17 in which the plurality of tapered rollers 6 and 6 are installed. Is blocking. With this configuration,
The inside and outside of this internal space 17 are shut off,
This prevents the grease for lubrication sealed in the inside from leaking to the outside, and also prevents foreign matters such as rainwater and dust from entering the inside space 17 from outside.

The outer end opening of the bearing housing 2 is closed by a cover 18 fixed to the outer end of the bearing housing 2.
The cover 18 is made of a synthetic resin or a metal material and has a substantially cylindrical shape with a bottom.
And an outward flange-like mounting portion 21 provided on the outer peripheral surface of the cylindrical portion 19 near the inner end (right end in FIG. 2).
In such a cover 18, the inner end of the cylindrical portion 19 is fitted inside the outer end of the bearing housing 2, and the mounting portion 21 is abutted against the outer end surface of the bearing housing 2. By fixing the mounting portion 21 to the outer end surface of the bearing box 2 with a bolt (not shown), the outer end opening of the bearing box 2 is closed.

Further, a sensor mounting hole 22 is formed in the middle portion of the bearing housing 2 at a portion located around the outer ring 4. A temperature sensor 23 such as a thermocouple is mounted on the outer peripheral surface of the outer ring 4 in the sensor mounting hole 22 so that the temperature of the double row rolling bearing unit 3 including the outer ring 4 can be detected. A harness 24 for taking out a detection signal of the temperature sensor 23 is taken out of the bearing box 2 through the sensor mounting hole 22 and sent to a controller (not shown).

In the case of the rolling bearing unit with sensor having the above-mentioned structure, the bearing box 2 supported on a bogie of a railway vehicle is used.
The axle 1 can be rotatably supported on the inside diameter side of the axle. or,
When the rotational resistance of the double-row tapered roller bearing 3 abnormally rises for some reason such as excessive skew of each of the tapered rollers 6, 6 and the temperature of the double-row tapered roller 3 rises, the temperature sensor 23 Detect this temperature. The temperature signal detected by the temperature sensor 23 is sent to the controller (not shown), and the controller issues an alarm such as turning on a warning light installed in the driver's seat. When such an alarm is issued, the driver takes measures such as an emergency stop.

[0010]

In the case of the conventional structure constructed and operated as described above, in order to mount the temperature sensor 23,
It is necessary to machine the sensor mounting hole 22 in the bearing housing 2. Since the bearing housing 2 is made of a high-strength material such as steel, the operation of forming the sensor mounting holes 22 in the bearing housing 2 is troublesome, which may increase the manufacturing cost of the rolling bearing unit with the sensor. Become. In addition, the operation of mounting the temperature sensor 23 on the outer peripheral surface of the outer ring 4 must be performed after the outer ring 4 is fitted inside the bearing box 2. Therefore, the temperature sensor 23 is inserted into the small-diameter sensor mounting hole 22, and the temperature sensor 23 is brought into contact with the outer ring 4 so that the temperature of the outer ring 4 can be detected. A troublesome operation such as preventing the sensor from dropping out of the sensor mounting hole 22 is required. For these reasons, the conventional rolling bearing unit with the sensor inevitably increases the cost. The rolling bearing unit with a sensor according to the present invention includes:
The present invention has been made in view of such circumstances.

[0011]

A rolling bearing unit with a sensor according to the present invention has an outer ring, an inner ring, a plurality of rolling elements, and a seal, similarly to the above-mentioned conventionally known rolling bearing unit with a sensor. A case, a seal ring, and a temperature sensor are provided. The outer ring and the inner ring are rotatable relative to each other, one of which is a rotating wheel and the other is a fixed wheel. Each of the rolling elements is rotatably provided between an outer raceway formed on the inner peripheral surface of the outer race and an inner raceway formed on the outer peripheral surface of the inner race. The seal case has a substantially cylindrical shape, and has a base end fixedly connected to an end of the fixed ring. The seal ring is provided between a peripheral surface of the seal case and a portion that rotates together with the rotating wheel. Further, the temperature sensor detects a temperature of the rolling bearing unit including the rolling elements.

In particular, in the rolling bearing unit with a sensor according to the present invention, the seal case is made of a metal having good heat conductivity such as a steel plate, an aluminum alloy plate, a copper alloy plate, and the base end is formed of the fixed ring. Is fixedly connected to this fixed ring by being fitted to the end of the ring by interference fit. Further, the temperature sensor is coupled and fixed to the seal case in a state where the detecting portion is in contact with or close to the outer surface of the seal case. For this purpose, for example, a tip portion of the seal case is bent in the radial direction to form a circular portion, and the temperature sensor is connected and fixed to an outer surface of the circular portion.

[0013]

According to the rolling bearing unit with a sensor of the present invention constructed as described above, the temperature of the rolling bearing unit portion can be effectively reduced despite the fact that it can be manufactured at low cost without any troublesome processing and assembling work. Can be measured. That is, in order to couple and fix the temperature sensor to the outer surface of the seal case, such as the outer surface of the ring portion forming the seal case, no particularly troublesome processing is required, and the joining and fixing work can be performed in a wide space. Therefore, the processing cost and the assembly cost of the parts can be reduced. In addition, the temperature of the seal case, which is fitted and fixed to the fixed wheel by interference fit, increases with the temperature of the fixed wheel, and the temperature of the seal case becomes substantially the same as the temperature of the fixed wheel. For this reason, the temperature of the rolling bearing unit including the fixed ring can be effectively measured by the temperature sensor in which the detection portion is brought into contact with the outer surface of the seal case.

[0014]

FIG. 1 shows a first embodiment of the present invention.
An example is shown. The features of the present embodiment are a mounting structure of a temperature sensor 23a for detecting the temperature of the double row tapered roller bearing 3, which is a rolling bearing unit, and the temperature sensor 23.
This is in the wiring structure of the harness 24a for extracting the detection signal a. Since the structure and operation of the other parts are the same as those of the above-described conventional structure, the same parts are denoted by the same reference numerals, and overlapping description is omitted or simplified. explain.

The seal case 15a fixed to the outer end (the left end in FIG. 1) of the outer ring 4 as a fixed ring is formed by bending a metal plate having good heat conductivity such as a steel plate, an aluminum alloy plate, a copper alloy plate or the like. By doing so, the whole is formed in a substantially cylindrical shape with a crank-shaped cross section. Such a seal case 15a is fixedly connected to the outer ring 4 by fitting the base end (the right end in FIG. 1) to the outer end of the outer ring 4 by tight fitting. Accordingly, the inner peripheral surface of the outer end of the outer ring 4 and the outer peripheral surface of the base end of the seal case 15a are in direct contact with each other over the entire circumference with a sufficient contact pressure. Therefore, heat transfer between the outer ring 4 and the seal case 15a is efficiently performed, and the temperatures of the outer ring 4 and the seal case 15a are substantially the same.

The distal end (outer end, left end in FIG. 1) of the seal case 15a fixed and connected to the outer end of the outer ring 4 in this manner is bent inward in the radial direction, thereby forming the circular ring 2
5 is assumed. Then, the outer side surface of the annular portion 25 (FIG. 1)
(The left side surface), the temperature sensor 23a is fixedly connected thereto. In order to fix the temperature sensor 23a to the ring 25, bonding, screwing, combined use of bonding and screwing, or the like can be employed. In any case, the temperature sensor 2
In a state where 3a is fixedly connected to the ring portion 25, the detecting portion of the temperature sensor 23a is brought into contact with or close to the outer surface of the ring portion 25. Further, if necessary, the outer surface of the temperature sensor 23a is covered with an adhesive. If the temperature sensor is covered with the adhesive in this way, even if a foreign substance such as rainwater enters the cover 18, the performance of the temperature sensor 23a can be prevented from being deteriorated by the foreign substance. Reliability and durability can be improved.

In the illustrated example, a relay connector 26 is provided in a part of the cylindrical portion 19 forming the cover 18 for closing the opening at the end of the bearing housing 2 so as to penetrate the cylindrical portion 19. An end of a harness 24a for extracting a signal from the temperature sensor 23a is connected to an inner end of the relay connector 26. At the same time, the temperature sensor 23
The end of the cord 27 for sending the signal a to a controller (not shown) is freely connectable to the outer end of the relay connector 26. In order to facilitate the connection work between the harness 24a and the cord 27 and the end of the relay connector 26, plugs are attached to the ends of the harness 24a and the cord 27, and these plugs are connected to each other. The end of the relay connector 26 can be electrically and mechanically detachable. However, the connection between the end of the harness 24a and the inner end of the relay connector 27 may be omitted, and the end of the conductor of the harness 24a may be directly connected to the conductor of the relay connector 27. .

According to the rolling bearing unit with a sensor according to the present invention having the above-described structure, the temperature of the rolling bearing unit portion can be effectively reduced despite the fact that the rolling bearing unit can be manufactured at low cost without complicated processing and assembly work. Can be measured. That is, the temperature sensor 23a is connected to the annular portion 25 of the seal case 15a.
The joining and fixing operation can be performed in a wide space by a method that does not require particularly troublesome processing such as bonding and screwing. That is, since the operation of connecting and fixing the temperature sensor 23a to the ring portion 25 can be performed before the base end of the seal case 15a is fitted and fixed to the end of the outer ring 4, the connection operation is easy. It is. Therefore, the processing cost and the assembly cost of the parts can be reduced.

Further, as described above, the temperature of the seal case 15a, which is fitted and fixed to the outer ring 4 by interference fit, is substantially equal to the temperature of the outer ring 4, so that the annular portion of the seal case 15a The temperature of the double-row tapered roller bearing 3 including the outer ring 4 can be effectively measured by the temperature sensor 23 a having the detection portion abutted on the detection portion 25. For this reason, when an abnormality such as seizure occurs in the double-row tapered roller bearing 3, it can be detected reliably and quickly, and further serious damage is given to the rotating support portion including the double-row tapered roller bearing 3. It can be prevented from occurring. If the temperature sensor 23a is mounted near the load zone (the upper part in the illustrated example) of the double-row tapered roller bearing 3, the temperature rise accompanying the heat generation of the double-row tapered roller bearing 3 can be detected more efficiently. It is preferred.

Since the temperature sensor 23a is installed outside the annular portion 25 of the seal case 15a,
The temperature sensor 23a does not touch a lubricant such as grease sealed in the internal space 17 of the double-row tapered roller bearing 3. Therefore, the temperature sensor 23a does not contaminate the lubricant, and the durability of the lubricant is sufficiently maintained. In addition, since the temperature sensor 23a is installed on the outer surface of the annular portion 25, the temperature sensor 23a is attached to the annular portion 25.
It is not necessary to form a through hole for inserting the a and the harness 24a. Therefore, leakage of grease from the internal space 17 and entry of foreign matter into the internal space 17 through the through holes provided in the annular portion 25 do not occur.

Further, in addition to the temperature sensor 23a, a vibration sensor for detecting vibration can be integrally mounted on the outer surface of the seal case 15a. When the vibration of the double row tapered roller bearing unit 3 including the outer ring 4 is detected by the vibration sensor via the seal case 15a, the outer ring track 7, the inner ring track 8, or each of the inner ring track 8 based on the rolling fatigue life is detected. An alarm can be issued by detecting separation of the rolling surfaces of the tapered rollers 6,6.

The abnormality detection of the rolling bearing unit such as the double-row tapered roller bearing 3 can be performed by providing at least one of the temperature sensor 23a and the vibration sensor. Further, it is preferable to provide a vibration sensor because the reliability of abnormality detection can be further improved.

The rolling bearing unit to which the present invention is applied is not limited to a double-row tapered roller bearing as shown in FIG.
Other roller bearings such as a cylindrical roller bearing and a self-aligning roller bearing, or various ball bearings such as a deep groove type and an angular type may be used. or,
The part where the temperature sensor is assembled on the outer surface of the seal case is
The outer peripheral surface of the cylindrical portion is not limited to the outer surface of the annular portion as illustrated. Furthermore, the shape of the bearing box for holding the outer ring may be a half-split type that suppresses only the load side of the radial load, such as the upper half of the outer ring.

[0024]

Since the present invention is constructed and operates as described above, the sensor-equipped rolling which can accurately measure the temperature of the rolling bearing unit and detect the abnormality of the rolling bearing unit with high reliability. A bearing unit can be realized at low cost.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an example of an embodiment of the present invention.

FIG. 2 is a sectional view showing an example of a conventional structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Axle 2 Bearing box 3 Double row tapered roller bearing 4 Outer ring 5a, 5b Inner ring 6 Tapered roller 7 Outer ring raceway 8 Inner ring raceway 9 Cage 10 Spacer 11a, 11b Annular member 12 Stepped surface 13 Bolt 14 End plate 15a, 15b Seal case 16a, 16b Seal ring 17 Internal space 18 Cover 19 Cylindrical part 20 Bottom plate part 21 Mounting part 22 Sensor mounting hole 23, 23a Temperature sensor 24, 24a Harness 25 Ring part 26 Relay connector 27 Code

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3J016 AA04 BB02 CA07 3J101 AA16 AA25 AA32 AA43 AA54 AA62 BA73 FA41 FA44 GA01 GA31 GA36 GA41 GA51

Claims (4)

[Claims] 1. One of an outer ring and an inner ring which rotate relative to each other is a rotating wheel and the other is a fixed wheel, and is formed on an outer ring raceway formed on an inner peripheral surface of these outer rings and an outer peripheral surface of the inner ring. A plurality of rolling elements rotatably provided between the inner ring raceway, a cylindrical seal case having a base end fixedly connected to an end of the fixed ring, and a peripheral surface of the seal case. A seal ring provided between the rotating body and the portion that rotates together with the rotating wheel, and a temperature sensor for detecting the temperature of the rolling bearing unit including the rolling elements. The base end is fitted and fixed to the end of the fixed ring by an interference fit, and the temperature sensor is in contact with or close to the detecting portion on the outer surface of the seal case. With this seal case facing Rolling bearing unit with sensor that is fixedly connected to the unit. 2. A cover for closing an end opening of a fixed wheel, and a relay connector provided so as to penetrate the cover, and a harness for extracting a signal of a temperature sensor is provided at an inner end of the relay connector. 2. The rolling bearing unit with a sensor according to claim 1, wherein an end of a cord for connecting and sending the signal to the controller is freely connectable to an outer end of the relay connector. 3. The temperature sensor according to claim 1, wherein the temperature sensor is connected to the seal case by at least one of bonding means and screwing means, and an outer surface of the temperature sensor is covered with an adhesive. A rolling bearing unit with a sensor according to any of the above. 4. The rolling bearing unit with a sensor according to claim 1, wherein a vibration sensor in addition to the temperature sensor is connected and fixed to the seal case.