JP2017048846A - Bearing/sensor attachment structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bearing/sensor attachment structure which does not need to exchange a bearing itself when a sensor is exchanged.SOLUTION: When attaching a sensor for detecting a state amount around a bearing to the rolling bearing 5 having an inner ring 51, an outer ring 52 and rolling bodies 53, a bearing inner-ring side female screw part 6 and a bearing outer-ring side male screw part 8 are formed at an end part of an external peripheral face or an internal peripheral face of at least either of the inner ring 51 and the outer ring 52 in a bearing axial line direction as bearing-side screw parts which are coaxial with a bearing axial line, a tone-ring side male screw part 7 and a cover-side female screw part 9 are formed as sensor-side screw parts which are screwed to the bearing-side screw parts 6, 8, and the bearing-side screw parts 6, 8 and the sensor-side screw parts 7, 9 are screwed to each other, and the sensor is attached to the rolling bearing 5. When exchanging the sensor, the screwing of the bearing-side screw parts 6, 8 and the sensor-side screw parts 7, 9 is released.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a bearing-sensor mounting structure, and is suitable, for example, when a self-power-generating sensor for detecting a state quantity around a rolling bearing is mounted on the rolling bearing.

  As a technique for attaching a self-power generation type sensor to a rolling bearing body, for example, there is one described in Patent Document 1 below. The principle of self-power generation is that, for example, a generator rotor and a stator are attached to an inner ring and an outer ring of a rolling bearing, respectively, and electric power is induced in a coil by a difference in rotational speed between the two. Therefore, the rotor is fixed to the inner ring and the stator is fixed to the outer ring. These fixations are performed by closely fitting the rotor to the inner ring and closely fitting the stator to the outer ring. In general, the close fitting includes fitting, press fitting, caulking and the like. Besides these, fixing methods such as adhesion and welding by ultrasonic waves or heat are known.

JP 2003-13983 A

However, in the fixing method such as fitting, press-fitting, caulking, adhesion, and welding, the sensor component and the bearing component are integrated. For example, if the sensor fails and needs to be replaced, It is necessary to replace the entire bearing.
The present invention has been made paying attention to the above-described problems, and an object of the present invention is to provide a bearing-sensor mounting structure that does not require replacement of the entire bearing when the sensor is replaced.

  In order to solve the above problems, according to one aspect of the present invention, there is provided a bearing-sensor mounting structure for attaching a sensor for detecting a state quantity around a bearing to a bearing including an inner ring, an outer ring, and a rolling element, A bearing-side screw portion formed on the outer circumferential surface of at least one of the inner ring and the outer ring or an end portion in the bearing axial direction of the inner circumferential surface and coaxial with the bearing axis, and formed on a sensor component and screwed into the bearing-side screw portion. Provided is a bearing-sensor mounting structure that includes a sensor-side screw portion, and that screw-fits the bearing-side screw portion and the sensor-side screw portion to attach the sensor to the bearing.

  According to the present invention, when the sensor is replaced, it is only necessary to release the screwing between the bearing-side screw portion and the sensor-side screw portion, so that it is not necessary to replace the entire bearing.

1 is an exploded perspective view of a bearing with a wireless sensor to which an embodiment of a bearing-sensor mounting structure of the present invention is applied. It is sectional drawing of the bearing-sensor mounting structure of FIG. It is sectional drawing which shows the modification of the bearing-sensor attachment structure of FIG. It is sectional drawing which shows the other modification of the bearing-sensor attachment structure of FIG. It is sectional drawing which shows the modification with which the bearing-sensor attachment structure of FIG. 1 differs.

The following embodiments exemplify apparatuses and methods for embodying the technical idea of the present invention, and the technical idea of the present invention is the material, shape, structure, arrangement, etc. of components. Is not specified as follows. The technical idea of the present invention can be variously modified within the technical scope defined by the claims described in the claims.
Hereinafter, a bearing-sensor mounting structure according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an exploded perspective view of a bearing with a wireless sensor to which the bearing-sensor mounting structure of this embodiment is applied, and FIG. 2 is a cross-sectional view of FIG. This bearing 1 with a wireless sensor includes a tone ring 2, a sensor unit 3, a cover 4, and a rolling bearing 5. Among these, the tone ring 2, the sensor unit 3, and the cover 4 constitute a sensor (wireless sensor). The rolling bearing 5 is a ball bearing, and a plurality of rolling elements (balls) 53 are interposed between the inner ring 51 and the outer ring 52 via the cage 54. The rolling elements 53 are preferably made of ceramics to prevent electrolytic corrosion. Further, the rolling element 53 can use rollers or the like instead of balls.

  The tone ring 2 is attached to the inner ring 51 of the rolling bearing 5, and periodic irregularities are formed at equal intervals on the outer periphery of a cylindrical body having the same diameter as the inner ring 51. The cover 4 is attached to the outer ring 52 of the rolling bearing 5, and one end in the axial direction of the cylindrical body having the same diameter as the outer diameter of the outer ring 52 protrudes inwardly in a disk shape, and the mounting surface 41 of the sensor unit 3 is formed. It is composed. A circular hole larger than the maximum outer diameter of the tone ring 2 is formed at the center of the mounting surface 41. The sensor unit 3 is attached to the attachment surface 41 of the cover 4 so as to be arranged on the outer periphery of the tone ring 2. The sensor unit 3 includes a sensor substrate 31 on which sensors (not shown) and a wireless transmission device are mounted, and a coil portion 34 in which a plurality of coils 33 each having a conductor wire wound around a yoke 32 made of a magnetic material are arranged. It is prepared for. The sensor substrate 31 and the coil portion 34 of the sensor unit 3 are attached to the attachment surface 41 of the cover 4 by screws or the like while being arranged in an arc shape so as to form a part of the outer ring of the tone ring 2. .

  The sensor unit 3 includes, for example, a power generation unit, a charging circuit, a secondary battery, a detection sensor, a wireless transmission unit, and the like. As will be described later, the AC voltage generated by the power generation unit is converted into a DC voltage by the charging circuit and supplied to the detection sensor and the wireless transmission unit, and the surplus is stored in the secondary battery. The detection sensor and the wireless transmitter operate by receiving power from the charging circuit and the secondary battery. Examples of the detection sensor include a rotation sensor that detects the rotational speed of the rolling bearing, a temperature sensor that detects the ambient temperature of the rolling bearing, a vibration sensor that detects vibration of the rolling bearing, a humidity sensor that detects the ambient humidity of the rolling bearing, and a rolling sensor. It affects the operation and performance of rolling bearings, such as gas sensors that detect gaseous hydrocarbons, hydrogen sulfide, ammonia, etc. that are generated due to oxidative degradation of bearing lubricating oil, and ultrasonic sensors that detect frictional noise generated in rolling bearings. One or more of various sensors for detecting a state quantity (physical quantity) around the rolling bearing is provided.

  When the sensor unit 3 is attached to the cover 4 and the cover 4 and the tone ring 2 are attached to the outer ring 52 and the inner ring 51 of the rolling bearing 5, respectively, the sensor unit 3 is connected to the cover 4 and the rolling bearing 5 as described above. The sensor unit 3 is disposed on the outer periphery of the tone ring 2 while being accommodated in between. In this state, for example, when the outer ring 52 of the rolling bearing 5 is fixed and the inner ring 51 rotates, the tone ring 2 rotates with the inner ring 51. As a result, the tone ring 2 rotates relative to the coil portion 34 of the sensor unit 3, and the relative position of the coil portion 34 that faces the irregularities on the outer periphery of the tone ring 2 changes. At this time, the distance between the call portion 34 and the outer circumferential unevenness of the tone ring 2 changes periodically, and the magnetic flux density generated in each coil 33 changes. Accompanying this change in magnetic flux density, an AC voltage is generated in each coil 33. To do. The generated AC voltage is converted into a DC voltage by the above-described charging circuit, for example, and supplied to each part of the sensor unit 3 as operating power. In addition to the power generation by the electromagnetic induction method, any power generation method such as an electrostatic induction method can be adopted.

  In this embodiment, in order to attach the tone ring 2, which is a component of the wireless sensor, to the inner ring 51 of the rolling bearing 5, a bearing inner ring side female thread portion (bearing side screw) is provided on the inner peripheral surface of one end in the axial direction of the inner ring 51. Part) 6 and a tone ring side male screw part (sensor side screw part) 7 is formed on the outer peripheral surface of one end of the tone ring 2 in the axial direction of the cylinder body. The bearing inner ring side female threaded portion 6 is a threaded portion coaxial with the bearing axis of the rolling bearing 5, and the tone ring side male threaded portion 7 is a threaded portion that is screwed into the bearing inner ring side female threaded portion 6. Similarly, one end in the axial direction on the same side of the outer ring 52 where the bearing inner ring side female thread portion 6 is formed in order to attach the cover 4 which is a component of the wireless sensor to the outer ring 52 of the rolling bearing 5. The bearing outer ring side male threaded portion (bearing side threaded portion) 8 is formed on the outer peripheral surface of the portion, and the cover 4 is covered on the inner peripheral surface of the other end in the axial direction of the cylindrical body of the cover 4 where the mounting surface 41 is not formed. A side female screw portion (sensor side screw portion) 9 is formed. The bearing outer ring side male threaded portion 8 is a threaded portion coaxial with the bearing axis of the rolling bearing 5, and the cover side female threaded portion 9 is a threaded portion that is screwed into the bearing outer ring side male threaded portion 8.

  Since a rotational force acts on the rolling bearing 5, it is desirable to take a measure to prevent loosening at the threaded portion connecting the bearing body and the sensor component. As a countermeasure against such loosening of the threaded portion, for example, when the rotational force acting on the bearing viewed from any direction of the bearing axis is clockwise, the screw of the threaded portion coaxial with the bearing axis is rotated clockwise. The screw can be tightened in the direction. For example, if the rotational force acting on the inner ring 51 of the rolling bearing 5 is counterclockwise when viewed from the sensor component side, the bearing inner ring side female thread 6 and the tone ring side male thread 7 are rotated clockwise. A tightening screw, a so-called normal screw, is used, and a reverse screw may be used if the rotational force is clockwise. Further, a high friction material having a large friction coefficient may be interposed between the bearing side screw portion and the sensor side screw portion. As this high friction material, for example, an acrylic anaerobic curable composition represented by dimethacrylate is generally used.

  Next, a modified example of the bearing-sensor mounting structure of the embodiment described above is shown in FIG. In the bearing with the wireless sensor shown in FIGS. 1 and 2, the sensor is attached only to one end of the rolling bearing 5 in the axial direction of the bearing. For example, as shown in FIG. A sensor may be attached to the end. In this case, the tone ring side male screw portion 7 and the cover side female screw portion 9 formed as the sensor side screw portion may be the same, but the inner ring 51 of the rolling bearing 5 has bearing inner ring side female screws at both ends in the bearing axial direction. The part 6 is formed, and the outer ring 52 is also formed with the bearing outer ring side male screw part 8 at both ends in the bearing axial direction.

  Next, another modification of the bearing-sensor mounting structure of the above-described embodiment is shown in FIG. In the bearing with the wireless sensor shown in FIGS. 1 and 2, the outer ring 52 is formed with a bearing outer ring side male screw part 8 as a bearing side screw part in order to attach the cover 4 to the outer ring 52 of the rolling bearing 5. A cover-side female screw portion 9 was formed as the sensor-side screw portion. In FIG. 4, instead of this, a bearing outer ring side female thread portion 10 is formed at one end portion in the bearing axial direction of the inner peripheral surface of the outer ring 52 of the rolling bearing 5, and the outer peripheral surface of the cylindrical body of the cover 4 is formed. Of these, the cover-side male screw portion 11 is formed at the end opposite to one end in the bearing axial direction where the mounting surface 41 is formed. The bearing outer ring side female threaded portion 10 is a threaded portion coaxial with the bearing axis of the rolling bearing 5, and the cover side male threaded portion 11 is a threaded portion that is screwed into the bearing outer ring side female threaded portion 10. Therefore, the cover 4 as the sensor component can be attached to the outer ring 52 of the rolling bearing 5 by screwing the bearing outer ring side female screw part 10 and the cover side male screw part 11 together. In this case as well, it is desirable to take the above-described measures against loosening.

  Next, a different modification of the bearing-sensor mounting structure of the embodiment described above is shown in FIG. In the bearing with the wireless sensor shown in FIGS. 1 and 2, in order to attach the tone ring 2 to the inner ring 51 of the rolling bearing 5, the inner ring 51 is formed with a bearing inner ring side female thread portion 6 as a bearing side thread portion. The tone ring side male screw portion 7 is formed as a sensor side screw portion. In FIG. 5, instead of this, a bearing inner ring side male thread portion 12 is formed at one end in the bearing axial direction on the inner circumferential surface of the inner ring 51 of the rolling bearing 5, and the inner circumference of the cylindrical main body of the tone ring 2. A tone ring side female thread portion 13 is formed at one end of the surface in the bearing axial direction. The bearing inner ring side male screw portion 12 is a screw portion coaxial with the bearing axis of the rolling bearing 5, and the tone ring side female screw portion 13 is a screw portion that is screwed into the bearing inner ring side male screw portion 12. Therefore, the tone ring 2 as the sensor component can be attached to the inner ring 51 of the rolling bearing 5 by screwing the bearing inner ring side male thread part 12 and the tone ring side female thread part 13 together. In this case as well, it is desirable to take the above-described measures against loosening.

  Thus, in the bearing-sensor mounting structure of this embodiment, when a sensor for detecting a state quantity around the bearing is attached to the rolling bearing 5 including the inner ring 51, the outer ring 52, and the rolling element 53, the inner ring 51 and the outer ring The bearing-side threaded portions 6, 8, 10, 12 that are coaxial with the bearing axis are formed at the bearing axial direction end of at least one outer peripheral surface or inner peripheral surface of 52, and the bearing-side threaded portions 6, 8, 10, Sensor-side screw portions 7, 9, 11, 13 screwed to 12 are formed on the tone ring 2 and the cover 4 which are sensor components, and the bearing-side screw portions 6, 8, 10, 12 and the sensor-side screw portion 7, 9, 11 and 13 are screwed together and the sensor is attached to the rolling bearing 5. Therefore, when the sensor is replaced, the bearing-side screw portions 6, 8, 10, 12 and the sensor-side screw portions 7, 9, 11, 13 are used. Just unscrew In it does not need to be replaced every rolling bearing 5.

In the above-described embodiment, the rolling bearing to which the wireless sensor is attached has been described. However, the sensor attached to the rolling bearing is not limited to this and can be applied to any sensor. In addition, the rolling bearing can be applied to any bearing having an outer ring, an inner ring, and a rolling element.
It goes without saying that the present invention includes various embodiments not described herein. Therefore, the technical scope of the present invention is defined only by the invention-specific matters described in the appropriate claims from the above description.

DESCRIPTION OF SYMBOLS 1 Bearing with wireless sensor 2 Tone ring 3 Sensor unit 4 Cover 5 Rolling bearing 6 Bearing inner ring side female thread part (bearing side thread part)
7 Tone ring side male thread (sensor side thread)
8 Bearing outer ring side male threaded part (bearing side threaded part)
9 Cover side female thread (sensor side thread)
10 Bearing outer ring side female thread (bearing side thread)
11 Cover side male thread (sensor side thread)
12 Bearing inner ring side male threaded part (bearing side threaded part)
13 Tone ring female thread (sensor thread)
51 Inner ring 52 Outer ring 53 Rolling element 54 Cage

Claims (3)

A bearing-sensor mounting structure for attaching a sensor for detecting a state quantity around the bearing to a bearing having an inner ring, an outer ring, and a rolling element,
A bearing-side screw portion that is formed on the outer circumferential surface of at least one of the inner ring and the outer ring or the bearing axial direction end of the inner circumferential surface and is coaxial with the bearing axis;
A sensor-side screw portion that is formed on a component part of the sensor and is screwed into the bearing-side screw portion;
A bearing-sensor mounting structure, wherein the sensor is mounted on the bearing by screwing the bearing-side screw portion and the sensor-side screw portion.   The bearing-sensor mounting structure according to claim 1, wherein the bearing-side screw portion and the sensor-side screw portion are screws that are tightened in a rotation direction of a rotational force acting on the bearing.   2. The bearing-sensor mounting structure according to claim 1, wherein a high friction material having a large friction coefficient is interposed between the bearing-side screw portion and the sensor-side screw portion.

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