JP2005098334A - Sealing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent degradation in detection accuracy of a magnetic sensor 15 along with displacement in an axial direction between the magnetic sensor 15 and a pulser ring 16, in a sealing device 8 incorporating the magnetic sensor 15 and pulser ring 16. <P>SOLUTION: A multipolar magnetic rotor 19 is bonded to an outer circumferential face of a cylindrical portion (outer cylindrical portion) of an annular core portion 18 to constitute the pulser ring 16. The multipolar magnetic rotor 19 is formed by bonding rubber or resin containing magnetic powders to an outer circumferential face of the cylindrical portion 18b of the annular core portion 18, and is magnetized in a radial direction so that north poles and south poles are alternately arranged in its circumferential direction. In the multipolar magnetic rotor 19, magnetic field lines looping between circumferentially neighboring magnetic poles are emitted on a magnetic sensor 15 side. Therefore, the magnetic field lines emitted from the multipolar magnetic rotor 19 are facilitated to enter a detection face of the magnetic sensor 15. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a sealing device incorporating a magnetic sensor and a pulsar ring.

When the sealing device as described above is used for an inner ring type rolling bearing, a magnetic sensor is attached to one end face of the non-rotating outer ring, and a magnetized ring is attached to one end face of the rotating inner ring via a support member. (See Patent Document 1). The support member has a cylindrical portion and a flange portion extending radially inward, and a magnetized ring is bonded to the outer peripheral surface of the cylindrical portion of the support member. The magnetized ring is formed by alternately magnetizing N poles and S poles in the circumferential direction using rubber containing magnetic powder as a base. The detection surface of the magnetic sensor is orthogonal to the detection surface of the magnetized ring.
Japanese Patent Laid-Open No. 2001-21576 (FIG. 1)

  In the above conventional example, since the detection surface of the magnetic sensor is orthogonal to the detection surface of the magnetized ring, when the magnetic sensor and the magnetized ring are displaced in the axial direction, the detection surface of the magnetic sensor and the magnetized surface are magnetized. The distance between the detection surface of the ring is increased, the rubber containing the magnetic powder must be increased to increase the magnetic force of the magnetized ring, and the magnetic sensor must be made more sensitive, rotating. The detector becomes large and the manufacturing cost increases.

  The present invention is a sealing device that combines a first seal ring fixed to a non-rotating outer ring member and a second seal ring fixed to a rotating inner ring member, wherein the first seal ring includes a magnetic sensor. Is attached to the second seal ring so that a pulsar ring detected by the magnetic sensor faces the magnetic sensor in a radial direction, and the pulsar ring is an outer periphery of the second seal ring. And a multipolar magnet rotor bonded to the outer peripheral surface of a cylindrical portion provided in the annular core metal, the multipolar magnet rotor being circumferentially based on rubber or resin containing magnetic powder It is characterized in that it is magnetized from the radial direction so that N poles and S poles are alternately arranged, and magnetic field lines that loop between the magnetic poles are emitted to the magnetic sensor side. That.

  In this case, since the detection surface of the magnetic sensor and the detection surface of the multipolar magnet rotor are configured to face each other in the radial direction, the multipolar magnet rotor is provided even if the magnetic sensor and the pulsar ring are slightly displaced in the axial direction. The magnetic field lines emitted from the magnetic field easily enter the detection surface of the magnetic sensor.

  In the sealing device of the present invention, even if the magnetic sensor and the pulsar ring multipole magnet rotor are displaced in the axial direction, it is possible to prevent the detection accuracy of the magnetic sensor from being lowered.

  1 to 5 show an embodiment of the present invention. In this embodiment, a description will be given in a state in which the seal device of the present invention is incorporated in the rolling bearing device 1 used on the driving wheel side of the automobile. 1, the left side of the rolling bearing device 1 is the vehicle outer side, and the right side is the vehicle inner side.

  The inner shaft member 3 is pivoted to the outer ring member 2 fixed non-rotatably via two rows of rolling elements (for example, balls) 4 and 5 arranged at equal intervals around the crowns 6a and 6b. It is supported so that it can rotate around its center.

  A flange portion 21 that extends radially outward is formed on the outer peripheral surface of the outer ring member 2. The outer ring member 2 is fixed in a non-rotating manner by fixing the flange portion 21 to the knuckle 9 which is a part of the vehicle body with the bolt 10.

  The inner shaft member 3 includes an inner shaft 31 and an inner ring 32 used for a single row angular ball bearing. The inner ring 32 is fitted on the inner side of the inner shaft 31 on the vehicle inner side. The inner ring 31 is rolled onto the inner shaft 31 by caulking the inner end of the inner shaft 31 radially outward. 32 is integrated.

  The two rows of rolling elements 4 and 5 are provided on the outer peripheral surface of the inner race 32 and the two race portions provided adjacent to the inner peripheral surface of the outer ring member 2 in the axial direction, the race portion provided on the outer peripheral surface of the inner shaft 31. It is interposed between each track part.

  A flange portion 34 that extends radially outward is integrally formed on the outer peripheral surface of the inner shaft 31 on the vehicle outer side. Although not shown, a brake disc and a wheel are attached to the flange portion 34. A shaft portion 13 formed integrally with the saddle-shaped outer ring 12 of the constant velocity joint (CVJ) is spline-fitted into the center hole of the inner shaft 31, and a nut is attached to the end portion of the shaft portion 13 on the vehicle outer side. The hook-shaped outer ring 12 is integrated with the inner shaft member 3 by screwing 14.

  First and second sealing devices 7 and 8 are attached to both sides in the axial direction between the outer ring member 2 and the inner shaft member 3. Both the sealing devices 7 and 8 prevent the lubricant in the annular space 11 in which the rolling elements 4 and 5 are disposed from leaking to the outside, and prevent intrusion of external muddy water or the like into the annular space 11. .

  Although not shown in detail, the first sealing device 7 disposed on the vehicle outer side has a configuration in which a rubber lip that is in sliding contact with the inner shaft 31 is bonded to a metal ring fitted in the outer ring member 2.

  As shown in FIG. 2, the second seal device 8 disposed on the vehicle inner side has a configuration in which a first seal ring 81 and a second seal ring 82 are combined, and is a so-called pack seal. The second seal device 8 includes a magnetic sensor 15 and a pulsar ring 16 as a rotation detector that detects the rotation state (rotation phase, rotation speed, rotation speed, rotation direction, etc.) of the inner shaft member 3 (inner shaft 31 and inner ring 32). Will be described in detail below.

  The first seal ring 81 is attached to the outer ring member 2 and has a configuration in which a main lip 84 and an auxiliary lip 85 are attached to a first metal ring 83. The first metal ring 83 has a cylindrical portion 83a and a flange portion 83b extending radially inward from the axial inner end of the cylindrical portion 83a, and the main lip 84 and the auxiliary lip 85 are formed on the inner periphery of the flange portion 83b. It is vulcanized and bonded. A resin outer casing 17 having a predetermined thickness is laminated on the entire outer peripheral surface of the cylindrical portion 83 a in the first metal ring 83, and the magnetic sensor 15 is embedded in the resin outer casing 17. A female connector 20 for connecting the magnetic sensor 15 and a harness (not shown) connected to the electronic circuit of the vehicle body projects radially outward at a predetermined position on the circumference of the resin exterior body 17. It is integrally formed in a state.

  By the way, in the region where the magnetic sensor 15 is arranged in the cylindrical portion 83a of the first metal ring 83, as shown in FIG. The window 83c has a size and shape that is larger than the outer shape of the magnetic sensor 15 as viewed from the radial direction, or is approximately the same size and shape as the outer shape of the magnetic sensor 15. By providing the window 83c in this way, no metal material is interposed between the opposing surfaces of the magnetic sensor 15 and the pulsar ring 16. The window 83c is provided in the first metal ring 83 so as not to reach the area where the radial lip 87 of the second seal ring 82 is in sliding contact. In addition, as shown in FIG. 5, the magnetic sensor 15 is arranged so that its detection surface is flush with the outer diameter side opening end of the window 83c. Further, a resin outer package 17 is filled in the window 83c.

  The second seal ring 82 is attached to the inner ring 32, and has a configuration in which a radial lip 87 is attached to the second metal ring 86. The second metal ring 86 has a cylindrical portion 86a and a flange portion 86b formed at one end so as to extend radially outward at an axial outer end of the cylindrical portion 86a, and a radial lip 87 on the outer periphery of the flange portion 86b. Is vulcanized and bonded. The pulsar ring 16 is attached to the second seal ring 82.

  Each lip 84, 85, 87 is made of rubber such as nitrile butadiene rubber (NBR), but may be made of an appropriate resin.

  The pulsar ring 16 is formed by bonding a multipolar magnet rotor 19 to an annular cored bar 18. The annular cored bar 18 has a configuration in which the axially outer end sides of the inner cylinder part 18a and the outer cylinder part 18b arranged concentrically inside and outside in the radial direction are integrally connected by an annular plate part 18c. The multipolar magnet rotor 19 is formed by alternately adhering rubber or resin such as hydrogenated nitrile butadiene rubber (H-NBR) containing magnetic powder to the outer peripheral surface of the outer cylindrical portion 18b of the annular cored bar 18 in the circumferential direction. It is magnetized from the radial direction so that the N pole and the S pole are arranged. In this multipolar magnet rotor 19, as shown in FIGS. 3 and 4, magnetic lines of force that loop between the magnetic poles adjacent in the circumferential direction are released to the outer diameter side. In addition, since the raw material of the multipolar magnet rotor 19 is wound around so as to cover the outer surface of the annular plate portion 18c, external moisture permeates from the fitting surface between the annular cored bar 18 and the second metal ring 86. Can be prevented. Such a material wraparound portion of the multipolar magnet rotor 19 may not be provided.

  The pulsar ring 16 is attached to the second seal ring 82 by fitting the inner cylindrical portion 18 a of the annular core 18 to the cylindrical portion 86 a of the second metal ring 86, and on the detection surface of the magnetic sensor 15. The detected surfaces of the pulsar ring 16 are opposed to each other in the radial direction. As a result, as shown in FIGS. 3 and 4, the magnetic field lines that loop between the magnetic poles adjacent in the circumferential direction in the multipolar magnet rotor 19 of the pulsar ring 16 are emitted to the outer diameter side and enter the detection surface of the magnetic sensor 15. It becomes like this.

  The first metal ring 83 is formed of a nonmagnetic material such as nonmagnetic stainless steel (JIS standard SUS304), for example, because the magnetic sensor 15 is attached. Further, the annular cored bar 18 is formed of a magnetic material such as magnetic stainless steel (JIS standard SUS430), for example, in order to provide a magnetic path for converging the magnetic lines of force emitted from the multipolar magnet rotor 19 toward the inner diameter side. Further, the resin outer package 17 for molding the magnetic sensor 15 is a non-magnetic resin material such as engineering plastics such as polyphenylene sulfide (PPS), polybutylene terephthalate (PBT), and polyamide (PA). Although not shown, a lubricant such as grease is enclosed in a space surrounded by the first seal ring 81 and the second seal ring 82.

  In such a second seal device 8, the first seal ring 81 and the second seal ring 82 to which the pulsar ring 16 is integrally attached are temporarily assembled, and the second metal ring 86 is attached to the inner ring. 32 is press-fitted into the shoulder portion 32 a of the outer peripheral surface 32, and the resin-made outer body 17 of the first seal ring 81 is press-fitted into the shoulder portion 2 a of the inner peripheral surface of the outer ring member 2. The first seal ring 81 is positioned by bringing the flange portion 17a into contact with the end surface 2b of the outer ring member 2 on the vehicle inner side. In such a state of attachment, the main lip 84 and the auxiliary lip 85 of the first seal ring 81 are brought into contact with the outer peripheral surface of the inner cylindrical portion 18a of the annular core 18 and the radial lip 87 of the second seal ring 82 is the first lip 87. The cylindrical part 83a of the metal ring 83 is brought into contact with the inner peripheral surface. Since the radial lip 87 is disposed outside the pulsar ring 16, the pulsar ring 16 can be prevented from being contaminated by dust or the like, and a decrease in detection accuracy can be avoided. Further, since the main lip 84 and the auxiliary lip 85 of the first seal ring 81 are separated from the rolling element 5 and the raceway portion, it is possible to prevent metal wear powder and the like generated by the rotation of the rolling element 5 from adhering to the pulsar ring 16. , A decrease in detection accuracy can be avoided.

  As described above, in the second sealing device 8, the multipolar magnet rotor 19 of the pulsar ring 16 is bonded to the outer peripheral surface of the outer cylindrical portion 18 b of the annular cored bar 18, and is adjacent in the circumferential direction of the multipolar magnet rotor 19. The configuration is such that the lines of magnetic force that loop between the matching magnetic poles are emitted toward the outer diameter side, that is, the magnetic sensor 15 side. Therefore, even if the magnetic sensor 15 and the pulsar ring 16 are displaced in the axial direction, the lines of magnetic force emitted from the multipolar magnet rotor 19 are likely to enter the detection surface of the magnetic sensor 15 and are not easily affected by the axial displacement. Thus, the detection accuracy by the magnetic sensor 15 does not decrease.

  In addition, in the above embodiment, the following merits are obtained.

  First, by providing a window 83c in the first metal ring 83, no metal material is interposed between the opposing surfaces of the magnetic sensor 15 attached to the first seal ring 81 and the pulsar ring 16 attached to the second seal ring 82. Therefore, the magnetic lines of force generated from the pulsar ring 16 during the rotation operation pass through the window 83c of the first metal ring 83, and the eddy current generated as the magnetic lines of force pass through the first metal ring 83 is the cause. Thus, the phenomenon that the detection operation of the magnetic sensor 15 is lowered does not occur. In addition to this, the facing distance between the magnetic sensor 15 and the pulsar ring 16 can be reduced, so that the detection accuracy of the magnetic sensor 15 can be increased.

  Secondly, since the pulsar ring 16 has a configuration in which the multipolar magnet rotor 19 is bonded to the outer cylindrical portion 18b of the annular core metal 18, the multipolar magnet rotor 19 does not swing in the radial direction even when it receives a rotational centrifugal force. . Thereby, the radial direction opposing space | interval of the pulsar ring 16 and the magnetic sensor 15 can be kept constant irrespective of the magnitude of centrifugal force.

  Third, since the pulsar ring 16 is separated from the second seal ring 82, they can be easily manufactured individually, and the manufacturing cost can be reduced. In particular, in the above embodiment, since the inner cylindrical portion 18a and the outer cylindrical portion 18b of the annular cored bar 18 are disposed within the axial width of the first seal ring 81 and the second seal ring 82, the second seal device It is not necessary to increase the axial width of the entire 8 and can contribute to compactness. Further, if the axial width of the pulsar ring 16 is maximized within a range in which the first seal ring 81 and the second seal ring 82 are opposed to each other in the axial direction, the pulsar ring 16 adheres to the side surface of the annular plate portion 18c of the annular core 18 Compared to such a case, it is possible to ensure a large area facing the magnetic sensor 15 and to increase the detection accuracy of the magnetic sensor 15 as much as possible.

  Fourth, the multipolar magnet rotor 19 of the pulsar ring 16 is provided separately from the radial lip 87 of the second seal ring 82, and the radial lip 87 is formed of rubber free of magnetic powder that can become abrasive particles. Therefore, it is possible to eliminate such aggression that the first metal ring 83 that is a contact partner of the radial lip 87 is worn. As a result, stable sealing performance can be exhibited over a long period of time.

  Hereinafter, other embodiments and application examples of the present invention will be described.

  (1) Although not shown, the sealing device 8 can be used for a rolling bearing device used on the driven wheel side of an automobile, and can be used in various places.

  (2) In the embodiment described above, the first metal ring 83 without the window 83c is also included in the present invention.

  (3) As the magnetic sensor 15, for example, as shown in FIG. 6, it can be a forward / reverse detection sensor including two sensor elements 22 a and 22 b such as a Hall element and a magnetoresistive element. The two sensor elements 22a and 22b are arranged apart from each other in the circumferential direction, and the arrangement interval is an interval (λ / 4) at which the mutual output phase is 90 degrees as shown in FIG. λ is the magnetization pitch of the multipolar magnet rotor 19. The magnetization pitch is the total length of the circumferential magnetization length of N poles and the circumferential magnetization length of S poles adjacent thereto. When one sensor element 22a outputs the rectangular wave signal of FIG. 7A, the other sensor element 22b is 90 ° out of phase with respect to the rectangular wave signal of FIG. 7A. Outputs a square wave signal. That is, when the facing state of the multipolar magnet rotor 19 with respect to the forward / reverse detection sensor changes according to the rotational speed or rotational direction of the multipolar magnet rotor 19, the sensor elements 22a of the forward / reverse detection sensor 15 correspond to the change. Since the phase relationship and the phase period of the rectangular wave signal from 22b change, the rotational phase, rotational speed, rotational speed, rotational direction, etc. of the inner ring member 3 can be determined by applying signal processing to both rectangular wave signals. Can be sought.

Sectional drawing of the rolling bearing apparatus incorporating the sealing device which concerns on one Embodiment of this invention. The figure which expands and shows the 2nd sealing apparatus of FIG. The front view which shows the rotation detector of FIG. The perspective view which shows typically the mode of the magnetic force line discharge | released from the pulsar ring of FIG. The perspective view which shows the 1st metal ring of FIG. Explanatory drawing when the magnetic sensor is a forward / reverse detection sensor The figure which shows the detection signal output from the forward / reverse detection sensor of FIG.

Explanation of symbols

2 outer ring member 3 inner shaft member 32 inner ring 8 second seal device 81 first seal ring 82 second seal ring 15 magnetic sensor 16 pulsar ring 18 annular cored bar 18a annular cored bar 18b annular cored bar 18c Annular plate part of annular core metal 19 Multi-pole magnet rotor

Claims (1)

A seal device that combines a first seal ring fixed to a non-rotating outer ring member and a second seal ring fixed to a rotating inner ring member,
A magnetic sensor is attached to the first seal ring,
The pulsar ring detected by the magnetic sensor is attached to the second seal ring so as to face the magnetic sensor in the radial direction,
The pulsar ring is composed of an annular core bar attached to the outer periphery of the second seal ring, and a multipolar magnet rotor bonded to an outer peripheral surface of a cylindrical portion provided in the annular core metal. Based on a rubber or resin containing powder, the magnetic poles that are magnetized from the radial direction so as to alternately arrange the N poles and the S poles in the circumferential direction and loop between the magnetic poles are emitted to the magnetic sensor side. A sealing device characterized by that.

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