JP2006022837A - Bearing device with sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bearing device with a sensor which materializes highly precise detection by precisely holding an air gap between a sensor and a tooth part for speed detection over the entire periphery. <P>SOLUTION: In an bearing device 10 with a sensor, an inner ring 17b is integrally formed with a slinger 22 and an encoder 23. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a sensor-equipped bearing device, and more particularly, to a sensor-equipped bearing device used for detection of an operating state of a bearing device incorporated in a moving body such as a mechanical device or a railway vehicle, an automobile, a transport vehicle, or preventive maintenance.

  2. Description of the Related Art Conventionally, in an axle bearing of a railway vehicle or the like, a wheel idling detection or a bearing abnormality detection (a bearing temperature detection for seizing detection or a vibration detection for bearing breakage detection) is performed using a sensor. As an example of a sensor-equipped bearing device, one in which a sensor is attached to a front lid of a bearing box is known (for example, see Patent Document 1).

  As shown in FIG. 4, the sensor-equipped bearing device 100 disclosed in Patent Document 1 includes a grease-sealed double-row tapered roller bearing 102 that supports the weight of the vehicle and supports the rotation of the axle 101. 101 is rotatably supported with respect to the bearing housing 103 via the double row tapered roller bearing 102. An end face retainer 104 is fixed to the end portion of the axle 101, and a plurality of speed detecting tooth portions 105 are formed at equal intervals in the circumferential direction on the outer diameter of the end face retainer 104. A sensor 107 is assembled to the front lid 106 fixed to the bearing box 103.

The sensor 107 is disposed to face the tooth portion 105 for speed detection while maintaining a predetermined gap. The sensor 107 includes a speed detection element, and counts a pulse signal associated with the rotation of the speed detection tooth portion 105 to detect the rotation. The sensor 107 detects temperature and vibration using a built-in temperature detection element and vibration detection element. Reference numeral 108 denotes an end face lid attached to the front lid 106.
JP 2003-90335 A

  By the way, in the bearing device with sensor 100 shown in FIG. 4, the end surface retainer 104 and the speed detecting tooth portion 105 are arranged at the shaft end of the axle 101, and the sensor 107 is also attached to the front lid 106. As the axial length around the bearing becomes longer, the entire bearing device becomes heavier and the unsprung weight increases. In addition, the air gap between the sensor 107 and the speed detection tooth portion 105 needs to be initially adjusted due to the fitting tolerance of the components, and there is a problem that the front lid 106 becomes obstructive at that time.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to accurately detect the air gap between the sensor and the tooth portion for speed detection over the entire circumference. Another object is to provide a sensor-equipped bearing device.

The above object of the present invention is achieved by the following configurations.
(1) a rolling bearing having a rotating wheel, a stationary wheel, and a rolling element that is rotatably disposed between the rotating wheel and the stationary wheel;
An encoder rotatable with the rotating wheel;
A sensor attached to the stationary wheel or a member fixed to the stationary wheel at a position facing the encoder in the radial direction;
With
The bearing device with a sensor, wherein the rotating wheel and the encoder have an integral structure.
(2) a seal case fixed to the stationary ring;
A slinger that is rotatable together with the rotating wheel and constitutes a sealing means facing the seal case;
Further comprising
The bearing device with a sensor according to (1), wherein the rotating wheel, the slinger, and the encoder have an integral structure.

  According to the sensor-equipped bearing device of the present invention, since the rotating wheel and the encoder are configured as an integral structure, the air gap between the sensor and the tooth for speed detection is accurately maintained over the entire circumference, Accurate detection can be performed.

  Hereinafter, a bearing device with a sensor concerning each embodiment of the present invention is explained in detail based on a drawing.

(First embodiment)
1 and 2 are longitudinal sectional views showing a sensor-equipped bearing device according to a first embodiment of the present invention. As shown in FIG.1 and FIG.2, the bearing apparatus 10 with a sensor of 1st Embodiment is a bearing apparatus with a sensor for railcars, and the axle shaft 11 supports and fixes the wheel which is not shown in figure. On the inner diameter side, it is rotatably supported by a grease-sealed double-row tapered roller bearing 13 which is a rolling bearing of the present invention.

  The double row tapered roller bearing 13 is loaded with a radial load due to the weight of various members and an arbitrary axial load. The double-row tapered roller bearing 13 is fitted in the bearing housing 12 and is fitted on the axle 11 with a single outer ring 15 having a pair of outer ring raceway surfaces 14 inclined in the shape of a conical surface on the inner circumferential surface. A pair of inner rings 17a and 17b having inner ring raceway surfaces 16a and 16b inclined in the shape of the outer peripheral surface.

  The double row tapered roller bearing 13 rolls the tapered rollers 18 and the tapered rollers 18 arranged in a plurality of rows between the outer ring raceway surface 14 of the outer ring 15 and the inner ring raceway surfaces 16a and 16b of the inner rings 17a and 17b. And an annular retainer 19 that is movably retained. Inside the double-row tapered roller bearing 13, a lubricant such as grease is sealed.

  An inner ring spacer 20 is assembled between the pair of inner rings 17a and 17b. Another inner ring spacer 21 is provided at the axial end of the inner ring 17 a opposite to the inner ring spacer 20. The other inner ring 17b includes a single inner ring unit 24 in which the slinger 22 and the encoder 23 are integrated. The inner ring unit 24 is fitted to the axle 11 with a predetermined tightening margin on the inner circumferential surface of the inner ring 17b, and is fitted to the axle 11 with a predetermined gap on the inner circumferential surfaces of the slinger 22 and the encoder 23. Yes. The end of the front lid 25 is in contact with the axial end of the inner ring unit 24 opposite to the inner ring spacer 20, and the inner ring unit 24 is secured by fastening the front lid 25 to the axle 11 with bolts 26. Positioned in the axial direction.

  A pair of seal cases 27 and 28 are assembled to both ends of the outer ring 15. The seal cases 27 and 28 are formed thin by pressing soft iron, and are formed in a cylindrical shape so that the outer diameter gradually decreases from the outer ring 15 side. An oil seal 29 is disposed between the seal case 27 and the inner ring spacer 21, and a front end portion 27a of the seal case 27 and a recess 21a provided in the inner ring spacer 21 so as to surround the front end portion 27a. The labyrinth seal 30 is comprised by this. On the other hand, between the seal case 28 and the slinger 22, a tip end portion 28 b bent at approximately 90 degrees from the flange portion 28 a of the seal case 28 extending radially inward toward the double row tapered roller bearing 13 side, and The labyrinth seal 31 as a sealing means is constituted by the concave portion 22a provided in the slinger 22 so as to surround the distal end portion 28b. Thereby, the lubricant enclosed in the double row tapered roller bearing 13 is prevented from leaking to the outside, and foreign matter is prevented from entering the double row tapered roller bearing 13.

  The encoder 23 includes a gear having a plurality of speed detection teeth 32 provided at equal intervals in the circumferential direction on its outer peripheral surface, and the magnetic characteristics change alternately and at equal intervals in the circumferential direction. . The encoder 23 is not limited to the above gear, and a magnet may be attached to the outer peripheral surface alternately with S poles and N poles at equal intervals.

  As shown in FIG. 1, a pair of bolts 33, 33 are fixed to the seal case 28 so as to protrude outward in the axial direction of the axle 11 at positions separated in the circumferential direction of the flange portion 28 a. The pair of bolts 33, 33 are screwed with locking nuts 36, 36 after passing through screw holes of a pair of flange portions 35, 35 formed on the side of the sensor housing 34. In addition, a bolt 37 is fixed to the seal case 28 so as to protrude radially outward from a cylindrical portion 28c from the flange portion 28a toward the outer ring 15 side. A locking nut 38 is screwed into the bolt 37 after being inserted into the flange portion 34 b of the sensor housing 34. Thereby, the sensor housing 34 is fixed to the seal case 28. The sensor housing 34 is formed with a sensor hole 34 a at the bottom and is sealed with a cover 39.

  The locking nuts 36, 36, and 38 are U nuts in which a friction ring having elasticity is incorporated at the end of the female screw portion (U nut is a registered trademark of Fuji Seimitsu Co., Ltd.). The loosening prevention nuts 36, 36, and 38 prevent free rotation when the friction ring presses the male threads of the bolts 33, 33, and 37 while being sufficiently screwed into the bolts 33, 33, and 37. Looseness can be prevented.

  The sensor housing 34 is made of an aluminum alloy obtained by subjecting an aluminum alloy such as A2017, A2024, A5056, A6061, and A7075 to an alumite treatment. The sensor casing 34 made of aluminum alloy is superior in mechanical strength to that made of plastic, and is lighter than that made of iron, and therefore places a burden on the seal case 28 to which the sensor casing 34 is attached. I don't spend it. In addition, since the aluminum alloy sensor housing 34 has a better thermal conductivity than a plastic housing, the bearing temperature can be accurately measured. Moreover, since the sensor housing | casing 34 surface-treats, such as an alumite process, to the aluminum alloy, it can further improve the corrosion resistance of aluminum. The surface treatment may be a normal plating treatment other than the alumite treatment, but the surface treatment using an anodic oxidation treatment such as alumite treatment is superior in film properties.

  A gap between the sensor housing 34 and the flange portion 28a is filled with a resin 40 such as silicon resin or epoxy resin. That is, the resin 40 is filled in the gap portion of the mounting surface between the iron seal case 27 and the aluminum alloy sensor housing 34, so that moisture does not enter the gap portion of the mounting portion, and the aluminum and iron Elution of the aluminum alloy based on the difference in reference potential does not occur. As a result, the durability of the sensor 41 can be increased.

  The sensor 41 includes a speed detection element 43, a temperature detection element 44, and an acceleration detection element (vibration detection element) 45 fixed on a substrate 42 disposed in the sensor housing 34. 10 driving conditions are detected with high accuracy.

  The speed detection element 43 is disposed in the sensor hole 34 a of the sensor housing 34 so as to face the tooth portion 32 formed on the outer peripheral surface of the encoder 23 in a non-contact manner, and is fixed to the axle 11. Is detected, and the rotation of the axle 11 is measured to generate, for example, a pulsed electric signal. The generated electric signal is sent to a control circuit (not shown) through the input / output signal cable 46 and monitored. When measuring the rotation direction, two speed detection elements 43 may be arranged in a position where the speed signal pulse is about 90 degrees in one sensor housing 34. The same effect can be obtained even if two sensor housings each having one speed detecting element 43 are attached. At this time, it is preferable to arrange the two sensor housings so that the pulse of the speed signal is about 90 degrees in phase as in the above-described configuration.

  In addition, if the purpose of use is only to measure the rotational speed, and it is necessary to measure the rotational direction of only some of the bearings, only a sensor housing having one speed detecting element 43 is manufactured, It is possible to measure the rotational speed and direction by attaching two sensor housings only to the bearings that require measurement in the rotational direction. By doing so, it is not necessary to increase the types of sensors to be manufactured, and cost reduction can be realized. When temperature or vibration detection is not required, the temperature detection element 44 or the vibration detection element 45 can be removed from the substrate 42, and variations with a single type of housing are possible.

  The temperature detecting element 44 is disposed on the seal case 28 side of the sensor housing 34 close to the tapered roller bearing 13, and constantly measures the atmospheric temperature inside the tapered roller bearing 13 transmitted through the seal case 28. By giving it to the control circuit, occurrence of seizure due to running out of the lubricant is prevented. At this time, since the labyrinth seal which is a non-contact seal is used as the sealing means, there is no heat generation, and the heat generation of the tapered roller bearing 13 can be accurately measured. In addition, since the sensor housing 34 is made of an aluminum alloy and the temperature detection element 44 is arranged on the seal case side with respect to other detection elements, the temperature of the seal case 28 can be measured more accurately. In addition, if silicon resin or the like having good thermal conductivity is filled between the sensor housing 34 and the flange portion 28a, the temperature can be measured with higher accuracy.

  The vibration detection element 45 is a sensor that detects vibration in the axial direction, and converts the vibration component applied to the tapered roller 18, the outer ring 15, and the inner rings 17 a and 17 b into an electric signal and sends it to the control circuit. Since the vibration detection element 45 measures only the vibration in the axial direction, it can accurately measure abnormal vibration such as peeling or scratching of the tapered roller bearing 13 and can also measure uneven wear of the axle 11 with high accuracy. . Further, the attachment position (phase) can be set at any place on the circumference.

  According to the sensor-equipped bearing device 10 configured as described above, since the inner ring 17b and the encoder 23 are configured as an integral structure, the accuracy of the coaxiality of the tooth portion 32 of the encoder 23 with respect to the axle 11 is improved. Swaying is suppressed. Accordingly, the air gap between the sensor 41 and the tooth portion 32 for speed detection is accurately maintained over the entire circumference, and accurate detection can be performed. As a result, not only the rotation speed but also the angular velocity can be detected with high accuracy, and the instantaneous slip of the wheel 11 can also be detected. Further, since the number of parts can be reduced, the maintenance cost can be reduced.

  In addition, since the slinger 22 is integrated with the inner ring 17b and the encoder 23, the number of parts is further reduced. Further, since the slinger 22 is fitted to the axle 11 with a predetermined gap, the press-fitting length when the inner ring unit 24 is press-fitted into the axle 11 is shortened, the pressure input is reduced, and the efficiency when the bearing is incorporated is improved. Go up. In addition, since the slinger and the inner ring are separate from each other in the past, fretting occurs due to a minute slip between both end faces, and the wear powder may enter the bearing and adversely affect the lubrication. Such a problem can be avoided by integrating the slinger 22 and the encoder 23 into an integral structure.

(Second Embodiment)
Next, the sensor-equipped bearing device of the second embodiment will be described with reference to FIG. FIG. 3 is a longitudinal sectional view of the sensor-equipped bearing device according to the second embodiment of the present invention. Note that the same or equivalent parts as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted or simplified.

  As shown in FIG. 3, in the sensor-equipped bearing device 50 according to the second embodiment, the inner ring 17 b, the slinger 22, and the encoder 51 are configured as an integral structure as in the first embodiment. However, the speed detection tooth portion 52 is formed in a separate ring shape, and is press-fitted into the cylindrical portion 54 of the inner ring unit 53 integrally formed with the inner ring 17 b and the slinger 22 to constitute the encoder 51. ing.

  Therefore, according to the sensor-equipped bearing device 50 of the second embodiment, since the speed detection tooth portion 52 is a separate body, the inner ring unit 53 can be simply configured, and the overall cost can be reduced. it can. Other configurations and operations are the same as those in the first embodiment.

In addition, this invention is not limited to each embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably.
For example, the rolling bearing is not limited to a double row tapered roller bearing, and various rolling bearings such as a double row deep groove ball bearing, an angular ball bearing, and a cylindrical roller bearing may be applied.
In addition, the detection element incorporated in the sensor only needs to include at least a speed detection element, and further includes at least one of a temperature detection element and an acceleration detection element in order to monitor the operation status of the bearing device with high accuracy. It is desirable.
Furthermore, in the present embodiment, the sensor mounting position is set below the axle, but may be disposed at any position around the axle as long as there is no interference with the axle box and the periphery of the axle box.
In this embodiment, a seal case is used as a member fixed to the stationary ring for mounting the sensor. However, the sensor may be mounted on the bearing box or may be mounted on the stationary ring. May be.

It is a front view which shows the bearing apparatus with a sensor of 1st Embodiment which concerns on this invention. It is a longitudinal cross-sectional view of the bearing apparatus with a sensor shown in FIG. It is a longitudinal cross-sectional view which shows the bearing apparatus with a sensor of 2nd Embodiment which concerns on this invention. It is sectional drawing of the conventional bearing apparatus with a sensor.

Explanation of symbols

10, 50 Bearing device with sensor 11 Axle 12 Bearing box 13 Tapered roller bearing (rolling bearing)
15 Outer ring (stationary ring)
17a, 17b Inner ring (rotating wheel)
18 Rolling elements 22 Slinger 23, 51 Encoder 24, 53 Inner ring unit 27, 28 Seal case 29 Oil seal 31 Labyrinth seal (seal means)
32, 52 Teeth for speed detection 34 Sensor housing 41 Sensor 43 Speed detection element 44 Temperature detection element 45 Acceleration detection element

Claims (2)

A rolling bearing having a rotating wheel, a stationary wheel, and a rolling element that is rotatably disposed between the rotating wheel and the stationary wheel;
An encoder rotatable with the rotating wheel;
A sensor attached to the stationary wheel or a member fixed to the stationary wheel at a position facing the encoder in the radial direction;
With
The bearing device with a sensor, wherein the rotating wheel and the encoder have an integral structure. A seal case fixed to the stationary ring;
A slinger that is rotatable together with the rotating wheel and that constitutes a sealing means facing the seal case;
Further comprising
The sensor-equipped bearing device according to claim 1, wherein the rotating wheel, the slinger, and the encoder have an integral structure.

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