JP2008249377A - Rotational speed detection device and rolling bearing device using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotational speed detection device which is improved so as to inhibit erosion of resin due to ingress of calcium chloride solution. <P>SOLUTION: The car body side of the jointing part 71 of the U shape elastic seal member 65 is extending out ward in a radial direction, the tip of which is forming the gap seal (second seal member) 75. The gap seal 75 is put between the resin member 22 and the inward flange 64 of the core metal 21. Because the gap seal 75 is put between the inward flange 64 of the core metal 21 and the resin member 22, the ingress of the calcium chloride solution etc. from the gap between the inward flange part 64 of the core metal 21 and the resin member 22 can be inhibited. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a rotation speed detection device, and more particularly to a rotation speed detection device that detects the rotation speed of a wheel of an automobile. The present invention also relates to a rolling bearing device using the rotational speed detection device.

  With the widespread use of anti-lock brake systems, it is necessary to provide a rotational speed detection device that detects the rotational speed of wheels used in the system, and this device is installed in a rolling bearing device. Therefore, it is necessary to downsize the rotation speed detection device.

For example, in the technique disclosed in Patent Document 1, a seal device that seals a gap between an inner ring that is a moving wheel of an axle and an outer ring that is a fixed wheel and a rotation speed detection device are integrated, so that as a whole, Achieving compactness.
JP 2000-346858 A

  However, in the technique shown in Patent Document 1, when used in an environment where the temperature change is unexpected, the gap between the metal core and the resin member is reduced due to the shrinkage of the resin or the difference in the expansion coefficient between the resin and the metal. There is a risk that water or the like may enter this gap. Since the entry of water or the like to the bearing side is prevented by the cored bar, water or the like does not directly enter the bearing part, but water or the like stays between the cored bar and the resin. In this case, in a snowy country, an aqueous solution in which calcium chloride, which is used as a snow melting agent in winter, has entered the gap between the metal core and the resin member, and stays in the gap generated between the metal core and the resin. The resin member is eroded and the sensor embedded in the resin member is exposed. There is also a risk that water or the like may directly touch the exposed sensor.

  The present invention has been made in view of such circumstances, and it is an object of the present invention to provide an improved rotational speed detection device capable of suppressing the erosion of a resin due to the penetration of an aqueous calcium chloride solution.

  The rotational speed detection device according to the present invention includes a fixed side metal bar fixed to a fixed member and having a recess, a rotary side metal bar fixed to the rotary member, and either the fixed side metal bar or the rotary side metal core. A first seal member fixed to one of them and slidably in contact with the other, and a sensor for detecting the rotational speed of the rotating member are embedded, and the portion in which the sensor is embedded is inserted and fixed in the concave portion of the fixed-side metal core And a second seal member that fills a gap formed between the fixed side metal core and the resin member.

  According to the present invention, since the second seal member that fills the gap generated between the fixed-side metal core and the resin member is provided, moisture such as an aqueous calcium chloride solution enters between the metal core and the resin member. This can prevent the erosion of the resin member. As a result, the speed can be reliably detected by the sensor.

  The second seal member is preferably composed mainly of a material resistant to calcium chloride.

  Since the second seal member is mainly composed of a material resistant to calcium chloride, the second seal member itself is not attacked by calcium chloride, and there is a gap generated between the metal core and the resin member over a long period of time. Can be filled. Therefore, it is possible to prevent the calcium chloride aqueous solution from entering between the metal core and the resin member for a long period of time, and the erosion of the resin member is further suppressed. As a result, the speed can be reliably detected by the sensor.

  In the rotational speed detection device according to the present invention, the main component of the second seal member is preferably nitrile rubber (NBR) or hydrogenated nitrile rubber (HNBR).

  Since the main component of the upper second seal member is nitrile rubber (NBR) or hydrogenated nitrile rubber (HNBR), the calcium chloride aqueous solution infiltrates between the metal core and the resin member with an inexpensive and versatile member. Can be prevented.

  In the rotational speed detection device according to the present invention, it is preferable that the second seal member is formed integrally with the first seal member.

  Since the second seal member is formed integrally with the first seal member, it is possible to prevent the calcium chloride aqueous solution from entering between the metal core and the resin member with an inexpensive and simple configuration.

  Moreover, the rotational speed detection apparatus concerning this invention is used suitably for a rolling bearing apparatus.

  According to the present invention, it is possible to provide an improved rotational speed detection device that can prevent the resin from being damaged by the penetration of the aqueous calcium chloride solution and protect the sensor.

  Hereinafter, an embodiment in which a rotational speed detection device according to the present invention is integrated with a seal device and applied to a rolling bearing device will be described with reference to FIGS. Here, FIG. 1 is a cross-sectional view of the rolling bearing device according to the present embodiment cut along a plane including the rotation shaft of the rotating member according to claim 1. The left is inside the vehicle and the right is outside the vehicle. FIG. 2 is a view of the rolling bearing device according to the embodiment as viewed from the vehicle body side (left side in FIG. 1). FIG. 3 is an enlarged view of a main part of FIG. 1 to 3, the same parts are denoted by the same reference numerals, and FIGS. 1 to 3 are also referred to in the following description.

First, the configuration of the rolling bearing device will be described in order.
The hub unit 1 includes a vehicle body side track member 3 fixed to the vehicle body side, a wheel side track member 4 to which a wheel is attached, and a plurality of hub units 1 arranged in two rows between the vehicle body side track member 3 and the wheel side track member 4. Are provided with a ball 5 that is a rolling element and a cage 6 that holds the balls 5 in each row.

  The vehicle body side track member 3 is a substantially cylindrical fixing member, and has a flange 13 to be attached to a knuckle 29 that is a suspension device for the vehicle body with a bolt on an outer peripheral portion. Two rows of outer ring raceways 12 that are in sliding contact with the balls 5 are formed on the inner peripheral surface.

  The wheel-side track member 4 includes a hollow shaft 14 and an inner ring 17. The hollow shaft 14 is a substantially cylindrical rotating member, and is provided with a flange portion 18 to which a plurality of bolts for mounting a wheel are fixed to an outer peripheral portion, and a raceway groove 15 that is in sliding contact with the ball 5. An inner ring 17 is fitted and fixed near the portion. A raceway groove 16 that is in sliding contact with the ball 5 is formed in the inner ring 17 so as to be parallel to the raceway groove 15 of the hollow shaft 14. Between the right end portion of the vehicle body side track member 3 and the hollow shaft 14, a seal member 20 made of an elastic seal and a cored bar is provided.

  Between the end of the inner ring 17 on the vehicle body side and the end of the vehicle body side track member 3 on the vehicle body side, a seal device 7 including the rotational speed detection device 2 is provided. The seal device 7 mainly includes a fixed side seal member 8 fixed to the vehicle body side track member 3 and a rotary side seal fixed to the wheel side track member 4, more specifically, the inner ring 17. It consists of member 9.

  The fixed-side seal member 8 includes a metal core 21, a resin member 22 integrated with the metal core 21 by insert formation, a sensor 11 resin-molded on the metal core 21, and an elastic seal member 65.

  As shown in FIG. 3 which is a partially enlarged view of the sensor peripheral portion, the core metal 21 of the fixed-side seal member 8 is formed in an annular shape by pressing a metal plate. That is, the metal core 21 is connected to the fitting cylindrical portion 61 fitted and fixed to the vehicle body side end portion of the vehicle body side track member 3 and the axially outward end portion of the fitting cylindrical portion 61 in the radial axial direction. A connecting portion 62 extending to the connecting portion 62, a moisture intrusion preventing cylindrical portion 63 extending in the axial direction toward the vehicle body, and a flange portion 64 extending in the radial direction extending to the moisture intrusion preventing cylindrical portion 63. Have. An elastic seal member 65 is bonded to the end of the flange portion 64. Further, the resin member 22 is molded in the axially outward recess formed by the fitting cylindrical portion 61, the connecting portion 62, and the moisture intrusion preventing cylindrical portion 63, that is, the concave portion according to claim 1. The cored bar 21 is made of a nonmagnetic metal such as SUS304 so that lines of magnetic force can easily enter the detection surface of the sensor 11.

  The resin member 22 has an annular shape, and the outer shape of the annular degree portion is substantially equal to the outer shape of the left end portion of the vehicle body side track member 3. Further, an overhanging portion 26 is provided that projects in the axial direction of the vehicle body and in the radial direction from the portion where the sensor 11 of the annular portion is embedded. A connector portion 27 for attaching a harness connecting the processing means provided on the vehicle body side and the sensor 11 is integrally formed at the upper end portion of the overhang portion 26. The connector part 27 is provided with a connector pin 28 for signals, and the sensor 11 and the connector pin 28 are connected via a lead wire 30.

  Further, the rotational speed detection device 2 includes a sensor 11 and wiring means such as a connector portion 27 for taking out the output of the sensor 11 to the outside, a connector pin 28 and a lead wire 30, and a signal processing means (not shown). The sensor 11 is a magnetic sensor, and faces the detection surface in the radial axis direction.

  The rotation-side seal member 9 includes a slinger 33 having a L-shaped cross section formed by pressing a metal plate, and a pulsar 10 fixed to the cylindrical portion 31. The slinger 33 is connected to the end portion of the inner ring 17 on the vehicle body side, and is connected to the end portion (left end portion) in the axial direction of the cylindrical portion 31 in the radial direction toward the vehicle body side track member 3. And an outwardly extending flange portion 32. An elastic seal member 65 fixed to the axial flange portion 64, that is, the first seal member according to claim 1 is in sliding contact with the outer peripheral flange portion 32 and the cylindrical portion 31.

  The elastic seal member 65 includes a U-shaped adhesive portion 71 adhered to the end of the inward flange portion 64, and the flange portion 32 of the rotation-side seal member 9 extending from the side surface of the adhesive portion 71 toward the vehicle body in the axial direction. An axial lip 72 slidably contacting the surface, a first radial lip 73 slidably contacting the cylindrical portion 31 of the rotation-side seal member 9 extending from the bottom surface of the adhesive portion toward the axial body and radially inward, and the bottom surface of the adhesive portion 71 And a second radial lip 74 extending inward in the axial direction and radially inward and in sliding contact with the outer peripheral cylindrical surface of the cylindrical portion 31 of the rotary side seal member 9. Further, the vehicle body side of the U-shaped adhesive portion 71 extends outward in the radial direction, and the tip thereof forms a gap seal 75, that is, a second seal member according to claim 1. The gap seal 75 is sandwiched between the inward flange portion 64 of the resin member 22 and the cored bar 21.

  The pulsar 10 generates magnetic force by alternately arranging N and S poles in order for the sensor 11 to be combined to output a rotation signal. An annular support member 66 and a magnetized body bonded thereto 67. The magnetized body 67 is formed by magnetizing magnetic powder using rubber as a binder. The magnetized body 67 has a magnetic force generating surface facing radially outward and is disposed so as to face the detection surface of the sensor 11 described above. Therefore, the magnetic force generated by the pulser 10 can be detected by the sensor 11, thereby detecting the rotation of the wheel side track member 4.

  The pulsar support member 66 includes a large-diameter cylindrical portion 68, a small-diameter cylindrical portion 69, and a connecting portion 70, and the small-diameter cylindrical portion 69 is an outer diameter portion of the portion facing the axial direction of the cylindrical portion 31 of the rotating side seal member 9. It is press-fitted into. The magnetized body 67 is bonded to the outer peripheral cylindrical portion of the large diameter cylindrical portion 68. Bending portions that are bonded to the surface of the connecting portion 70 on the vehicle body side are respectively provided at the vehicle body side end portion of the magnetized body 67. The gap between the magnetized body 67 and the moisture intrusion preventing cylindrical portion 63 is set to a value as small as possible within a range where they do not contact each other.

  The sensor 11 is disposed between the fitting cylindrical portion 61 that is a large-diameter cylindrical portion and a moisture intrusion-preventing cylindrical portion 63 that is a small-diameter cylindrical portion, and is disposed in the resin member 22. A wire takeout notch portion 47 for passing the lead wire 30 connecting the sensor 11 and the signal processing means is provided at the end of the fitting-side cylindrical portion 61 of the core metal 21 of the fixed-side seal member 8 in the axial vehicle body side. It has been.

  In such a rotational speed detection device, the intrusion of moisture that has entered from the position indicated by A into the pulsar 10 side is prevented by the elastic seal member 65. Further, since the gap seal 75 is sandwiched between the inward flange portion 64 of the core metal 21 and the resin member 22, the inward flange portion 64 of the core metal 21 or the moisture intrusion preventing cylindrical portion 63 and the resin member 22. Moisture does not enter through the gap. The elastic seal member 65 is mainly composed of hydrogenated nitrile rubber (HNBR).

  According to the wheel rolling bearing device using the rotational speed detection device of the above embodiment, the following effects can be obtained.

  (1) In the above-described embodiment, the second seal member that fills the gap generated between the core metal 21 and the resin member 22 as described above, that is, the gap seal 75 is sandwiched. Therefore, it is possible to prevent moisture such as a calcium chloride aqueous solution from entering between the metal core 21 and the resin member 22, and erosion of the resin member 22 is suppressed. As a result, the speed can be reliably detected by the sensor.

  (2) In the above embodiment, the gap seal 75 that is the second seal member is integrally formed with the elastic seal member 65 that is the first seal member. Therefore, it is possible to prevent the calcium chloride aqueous solution from entering between the metal core and the resin member with an inexpensive and simple configuration.

  (3) The second seal member is mainly composed of nitrile rubber (NBR), which is a material resistant to calcium chloride. Therefore, it is possible to prevent the calcium chloride aqueous solution from entering between the metal core and the resin member with an inexpensive and versatile member. Therefore, the gap seal 75 itself as the second seal member is not affected by calcium chloride, and the gap generated between the cored bar 21 and the resin member 22 can be filled for a long time. Therefore, it is possible to prevent the calcium chloride aqueous solution from entering between the metal core 21 and the resin member 22 for a long period of time, and the erosion of the resin member 22 is suppressed. As a result, the speed can be reliably detected by the sensor.

  In addition, you may change the said embodiment as follows.

  In the above embodiment, the gap seal 75 is formed of a material mainly composed of hydrogenated nitrile rubber (HNBR), but may be formed of a material mainly composed of nitrile rubber (NBR). Although the chemical resistance is lowered by forming the nitrile rubber (NBR) as a main component, the cold resistance of the gap seal 75 can be improved and can be manufactured at a lower cost.

  In the above embodiment, the gap seal 75 is integrally formed with the elastic seal member 65, but may be formed separately. According to this configuration, the gap seal 75 can be formed of a material different from that of the elastic seal member 65, and an optimal raw material can be used for the gap seal 75 without being limited by the properties required as an elastic seal.

  In the above embodiment, the magnetized body 67 is installed in the radial direction, but it may be a rolling bearing device for a wheel using a rotational speed detection device in a form installed in the magnetized body axial direction. In short, it is only necessary to have a structure capable of preventing moisture from entering between the resin member and the cored bar by inserting a gap seal between the resin member and the cored bar.

The sectional view by the plane containing the central axis of the wheel of the rolling bearing device concerning one embodiment of the present invention. The figure which looked at the rolling bearing apparatus concerning one Embodiment of this invention from the vehicle body side. The partial enlarged view of the rolling bearing apparatus concerning one Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hub unit 2 Rotational speed detection apparatus 3 Car body side track member 4 Wheel side track member 5 Ball 6 Cage 7 Cage 7 Sealing device 8 Fixed side seal member 9 Rotation side seal member 10 Pulsar 11 Sensor 12 Outer ring track 13 Flange 14 Hollow shaft 15 Track Groove 16 Track groove 17 Inner ring 18 Flange portion 20 Seal member 21 Core metal 22 Resin member 23 Elastic seal (first seal member)
26 Overhang portion 27 Connector portion 28 Connector pin 29 Knuckle 30 Lead wire 31 Cylindrical portion 32 Flange portion 33 Slinger 47 Notch portion 61 Fitting cylindrical portion 62 Connecting portion 63 Moisture intrusion preventing cylindrical portion 64 Flange portion 65 Elastic seal member 66 Support member 67 Magnetized body 68 Large-diameter cylindrical portion 69 Small-diameter cylindrical portion 70 Connecting portion 71 Adhesive portion 72 Axial lip 73 Radial lip 74 Radial lip 75 Clearance seal (second seal member)

Claims (5)

A fixed metal core fixed to the fixing member and having a recess;
A rotating side metal bar fixed to the rotating member;
A first seal member fixed to one of the fixed side metal core and the rotation side metal core and in sliding contact with the other;
While embedding a sensor for detecting the rotation speed of the rotating member, a resin member in which the portion in which the sensor is embedded is inserted and fixed in the concave portion of the fixed side metal bar,
A rotational speed detection apparatus comprising: a second seal member that fills a gap generated between the fixed side metal core and the resin member.   The rotational speed detection device according to claim 1, wherein the second seal member is mainly composed of a material resistant to calcium chloride.   The rotational speed detection device according to claim 2, wherein the second seal member is mainly composed of nitrile rubber or hydrogenated nitrile rubber.   The rotational speed detection device according to any one of claims 1 to 3, wherein the second seal member is formed integrally with the first seal member.   The rolling bearing apparatus using the rotational speed detection apparatus of any one of Claims 1-4.

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