JP2009019741A - Hermetically sealing device with magnetic encoder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve bonding strength between a slinger and a pulser ring of magnetic rubber material bonded to a flange of the slinger in a hermetically sealing device. <P>SOLUTION: The hermetically sealing device with a magnetic encoder includes the slinger 13 comprising a sleeve 131 attached to the outer circumference of a rotary side member 202 and the flange 132 extending from one end of the sleeve 131 in the axial direction, the pulser ring 14 of the magnetic rubber material, multipole magnetized and integrally bonded to an outer surface of the flange 132, and a thrust lip 121 provided on a stationary side member 201 and slidably brought into close contact with an inner surface of the flange 132. Beads 141 continuous in the circumference direction are provided at positions of the inner surface of the flange 132 on the inner peripheral side rather than a sliding portion S1 with respect to the thrust lip 121. The beads 141 are made of part of the magnetic rubber material continuous with positions near the inner circumference of the pulser ring 14 via a plurality of small holes 132a formed in the flange 132 in the circumference at predetermined intervals. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a sealing device with a magnetic encoder in which a magnetic encoder is provided together with the sealing device.

  In the anti-lock brake system of automobiles, the rotation of wheels is monitored by a magnetic encoder in order to control the braking force by hydraulic pressure, and as such a magnetic encoder, a sealing device for sealing a wheel hub bearing is used. There is something attached. FIG. 4 is a half sectional view showing this type of conventional sealing device with a magnetic encoder cut along a plane passing through the axis O, and FIG. 5 is a slinger and a pulsar integrated therewith in the conventional sealing device with a magnetic encoder. It is a partial section perspective view showing a ring.

  The sealing device 100 shown in FIG. 4 is incorporated between the outer ring 201 of the hub bearing 200 and the end of the inner ring 202 to prevent the intrusion of muddy water or the like from the outside of the bearing into the inside of the bearing. A metal mounting ring 101 that is press-fitted to the peripheral surface, and a thrust strip 102 and a radial lip 103 made of a rubber-like elastic material provided integrally with the mounting ring 101 are provided. The inner peripheral surface of the flange 104a of the slinger 104, which is closely fitted to the outer peripheral surface 202, is slidably in contact, and the radial lip 103 on the inner peripheral side is slidable on the outer peripheral surface of the sleeve 104b of the slinger 104. Have been close to.

  On the outer surface of the flange 104a of the slinger 104, as shown in FIG. 5, a pulsar ring 105 formed of a magnetic rubber material in which a magnetic material is mixed with a rubber-like elastic material and magnetized at a predetermined pitch in the circumferential direction. Are provided integrally. Further, as shown in FIG. 4, a magnetic sensor 106 is opposed to the outside of the pulsar ring 105 in a non-rotating state, and this magnetic sensor 106 constitutes a magnetic encoder together with the pulsar ring 105. Thus, the pulser ring 105 generates a pulse having a waveform corresponding to a change in the magnetic field due to the integral rotation with the inner ring 202 of the bearing 200, and detects the rotation.

Further, the flange 104a of the slinger 104 is provided with a plurality of holes 104c located on the outer peripheral side with respect to the sliding portion with the thrust strip 102 and arranged at predetermined intervals in the circumferential direction. It is molded by filling a magnetic rubber material for molding through the hole 104c from the side opposite to the molding surface of the pulsar ring 105 in 104a (for example, see Patent Document 1 below).
JP-A-11-281659

  Here, since the slinger 104 is used in a harsh environment where muddy water due to rainfall comes in, stainless steel that does not rust easily is used, but since stainless steel has a relatively weak adhesive force with rubber material, pulsar ring There is a concern about peeling of 105. Moreover, when it contacts with seawater etc., there is a concern that the pulsar ring 105 may be peeled off due to a reaction with salt.

  On the other hand, in the above prior art, a part 105 a of the magnetic rubber material forming the pulsar ring 105 is filled in the hole 104 c formed in the flange 104 a of the slinger 104, and the sliding portion with the thrust strip 102 is The pulsar ring 105 is firmly connected to the flange 104a at the outer peripheral portion because it wraps around the outer peripheral side. However, in this configuration, if peeling occurs at the inner peripheral end portion 105b of the pulsar ring 105, centrifugal force is generated. As a result, the peeling easily proceeds, and the rotation detection accuracy of the pulsar ring 105 may be adversely affected.

  The present invention has been made in view of the above points, and its technical problem is to improve the bonding strength with a pulsar ring made of a magnetic rubber material bonded to a flange of a slinger in a sealing device. It is in.

  As a means for effectively solving the above technical problem, a sealing device with a magnetic encoder according to the invention of claim 1 is a slinger comprising a sleeve attached to the outer periphery of a rotating side member and a flange developed from one axial end thereof. And a pulsar ring formed of a magnetic rubber material, multipolar magnetized and integrally joined to the outer surface of the flange, and a thrust provided on a stationary member and slidably in contact with the inner surface of the flange A bead continuously provided in the circumferential direction at a position on the inner surface of the flange and on the inner circumferential side of the sliding portion with the thrust strip. The bead is circumferentially provided on the flange. It consists of a part of magnetic rubber material which continued with the inner peripheral part of the said pulsar ring through the several small hole opened by the predetermined space | interval. The magnetic rubber material referred to here is a rubber-like elastic material in which fine powders of a magnetic material are uniformly mixed.

  A sealing device with a magnetic encoder according to a second aspect of the present invention is the sealing device according to the first aspect, wherein the outer peripheral end of the pulsar ring passes through the outer peripheral edge of the flange of the slinger, and the thrust strip on the inner surface of the flange It extends so that it may go around to the outer peripheral side of the sliding part.

  According to the sealing device with a magnetic encoder according to the first aspect of the present invention, the pulsar ring has a part of the magnetic rubber material in the small hole formed at a predetermined interval in the circumferential direction on the flange of the slinger at the inner peripheral portion thereof. Through the bead provided on the inner surface of the flange, the separation from the inner peripheral portion and the progress of the separation are prevented. It becomes a structure that is difficult to advance to the circumferential side. Moreover, since the bead is continuously formed in the circumferential direction at a position on the inner peripheral side from the sliding part between the flange and the thrust strip, the foreign matter that has entered the inner peripheral side from the sliding part is Further penetration into the inner peripheral side is prevented by the bead, and the thrust is pushed back to the outer peripheral side of the thrust strip by the swinging action by the rotation of the flange, so that the sealing performance is improved.

  According to the sealing device with a magnetic encoder according to the second aspect of the present invention, occurrence of peeling at the outer peripheral portion of the pulsar ring is also effectively prevented.

  Hereinafter, a preferred embodiment of a sealing device with a magnetic encoder according to the present invention will be described with reference to the drawings. FIG. 1 is a half sectional view of a mounted state in which this embodiment is cut by a plane passing through an axis O, and FIG. 2 is a partial sectional perspective view showing a slinger and a pulsar ring integrated therewith in FIG. 3 and 3 are partial cross-sectional perspective views of the slinger and pulsar ring of FIG. 2 as seen from a different direction from FIG.

  First, in FIG. 1, reference numeral 200 is a wheel hub bearing, and includes an outer ring 201, an inner ring 202, and a large number of steel balls (not shown) arranged so as to be able to roll therebetween. The sealing device 1 for sealing the bearing 200 includes a metal mounting ring 11 attached to the inner periphery of the outer ring 201, a seal body 12 provided integrally with the mounting ring 11, and the inner ring 202 of the bearing 200. A slinger 13 attached to the outer periphery and a pulsar ring 14 integrally joined to the slinger 13 are provided. The outer ring 201 corresponds to a “stationary member” described in claim 1, and the inner ring 202 corresponds to a “rotation member” described in claim 1.

  The mounting ring 11 in the sealing device 1 is manufactured by pressing a metal plate or the like, and includes a cylindrical outer peripheral cylindrical portion 11a press-fitted to the inner peripheral surface of the outer ring 201 of the bearing 200, and the outer periphery thereof. It consists of an inward flange 11b extending in the inner diameter direction from the end of the cylindrical portion 11a facing the bearing.

  The seal body 12 in the sealing device 1 is made of a rubber-like elastic material and includes a thrust strip 121, a radial lip 122, and a grease lip 123. Of these, the thrust strip 121 has a conical cylindrical shape with a tip having a large diameter from a base elastic layer 124 formed of a rubber-like elastic material on the surface of the inward flange 11b of the mounting ring 11 opposite to the inside of the bearing. The radial lip 122 is located on the inner peripheral side of the thrust strip 121 and extends from the inner peripheral end of the base elastic layer 124 in a conical cylindrical shape having a small diameter at the tip. The grease lip 123 extends from the inner peripheral end of the base elastic layer 124 toward the side opposite to the radial lip 122 (inner side of the bearing) in a conical cylindrical shape having a small diameter at the tip.

  Further, a part of the base elastic layer 124 goes around the outer periphery of the tip of the outer peripheral cylindrical portion 11a in the mounting ring 11, and an outer peripheral seal portion 125 that is in close contact with the inner peripheral surface of the outer ring 201 of the bearing 200 with an appropriate crushing margin. It has become.

  The slinger 13 is made of stainless steel. The sleeve 131 is press-fitted to the outer peripheral surface of the inner ring 202 of the bearing 200, and the end of the sleeve 131 facing the outside of the bearing extends in a disk shape in the outer diameter direction. And flange 132. The thrust strip 121 in the seal body 12 is in close contact with the inner surface of the flange 132 in the slinger 13 so that the entire circumference of the tip is slidable, and the radial lip 122 is in the vicinity of the tip on the outer periphery of the sleeve 131 in the slinger 13. The entire periphery of the inner peripheral edge portion is slidably in close contact, and the grease lip 123 is in close proximity to the outer peripheral surface of the sleeve 131 on the inner side of the bearing than the radial lip 122.

  The pulsar ring 14 is formed into a disk shape from a magnetic rubber material in which a magnetic fine powder such as ferrite or rare earth is mixed with a rubber-like elastic material, and the outer surface of the flange 132 in the slinger 13 (surface facing the outside of the bearing). As shown in FIG. 3, the S pole and the N pole are alternately magnetized (multipolar magnetization) at a predetermined pitch in the circumferential direction.

  As shown in FIG. 3, the inner surface of the flange 132 of the slinger 13 (the surface opposite to the pulsar ring 14) on the inner peripheral side of the sliding portion S <b> 1 with the thrust strip 121 in the circumferential direction. A continuous bead 141 is provided. The bead 141 is made of a part of a magnetic rubber material that is continuous with the pulsar ring 14 through a plurality of small holes 132a formed in the flange 132 at predetermined intervals in the circumferential direction. In other words, each small hole 132 a has a connecting portion 142 made of a magnetic rubber material that connects the pulsar ring 14 and the bead 141.

  On the other hand, the outer peripheral end portion 143 of the pulsar ring 14 extends through the outer peripheral edge of the flange 132 of the slinger 13 so as to go around to the outer peripheral side of the sliding portion S1 with the thrust strip 121.

  On the outer side in the axial direction of the pulsar ring 14, a magnetic sensor 15 that constitutes a magnetic encoder together with the pulsar ring 14 is disposed in a non-rotating state. The magnetic sensor 15 generates a pulse signal corresponding to a change in the magnetic field.

  According to the sealing device 1 with a magnetic encoder configured as described above, the thrust strip 121 in the non-rotating seal body 12 slides with the flange 132 of the slinger 13 that rotates integrally with the inner ring 202 of the bearing 200. In this case, intrusion of muddy water or the like from the outside of the bearing is prevented by swinging off the flange 132 by centrifugal force. In addition, a radial seal 122 in the seal main body 12 is in close contact with the outer peripheral surface of the sleeve 131 of the slinger 13 on the inner side, thereby achieving a double seal. Even if muddy water or the like from the outside slightly passes through the sliding portion S1 due to the thrust strip 121 to the inner peripheral side thereof, it continues in the circumferential direction on the inner peripheral side of the sliding portion S1. The bead 141 formed in this manner functions like a dam and prevents further intrusion into the inner peripheral side. Therefore, the bead 141 is eventually pushed back to the outer peripheral side of the sliding portion S1 by the swinging action by the rotation of the flange 132. . For this reason, it is possible to effectively prevent muddy water or the like that has passed through the sliding portion S1 from entering the sliding portion between the sleeve 131 of the slinger 13 and the radial lip 122 and maintain a stable sealing performance. Is done.

  Further, when the pulsar ring 14 rotates integrally with the inner ring 202, the N pole and the S pole magnetized by the pulsar ring 14 alternately pass in the rotation direction through the front surface of the detection surface of the magnetic sensor 15. Since a pulse-like signal having a waveform corresponding to the change in the magnetic field due to is output from the magnetic sensor 15, rotation can be measured by counting the pulses.

  Here, the pulsar ring 14 made of a magnetic rubber material is in a harsh environment in which earth and sand and muddy water from the road surface fly when the vehicle travels. The pulsar ring 14 has an outer peripheral end 143 and a flange 132 of the slinger 13. Since it is formed so as to surround the outer peripheral edge in a U-shape, peeling is less likely to occur. Further, a portion closer to the inner periphery of the pulsar ring 14 is connected to the flange 132 via the connecting portions 142 made of magnetic rubber material in a plurality of small holes 132a formed in the flange 132 of the slinger 13 at predetermined intervals in the circumferential direction. Since the inner surface is connected to the bead 141 continuously formed in the circumferential direction, even if the inner peripheral end portion 14a of the pulsar ring 14 is peeled off from the flange 132, the peeling is caused by the connecting portion 142. It does not progress further to the outer peripheral side.

  Therefore, even if the slinger 13 is made of stainless steel having a relatively weak adhesive force with the rubber material, it is possible to effectively prevent the pulsar ring 14 from being peeled off by muddy water or salt water. A decrease in detection accuracy can be effectively prevented.

1 is a half sectional view of a mounting state in which a preferred embodiment of a sealing device with a magnetic encoder according to the present invention is cut along a plane passing through an axis O. FIG. FIG. 2 is a partial sectional perspective view showing a slinger and a pulsar ring integrated with the slinger in FIG. 1. FIG. 3 is a partial cross-sectional perspective view of the slinger and pulsar ring of FIG. 2 viewed from a direction different from FIG. 2. It is sectional drawing which cut | disconnects and shows the conventional sealing device with a magnetic encoder by the plane which passes along the axial center O. FIG. It is a fragmentary perspective view which shows the slinger and the pulsar ring integral with this in the conventional sealing device with a magnetic encoder.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Sealing device 11 Mounting ring 12 Seal main body 121 Thrust strip 122 Radial lip 123 Grease lip 13 Slinger 131 Sleeve 132 Flange 132a Small hole 14 Pulsar ring 141 Bead 142 Connection part 143 Outer peripheral edge 15 Magnetic sensor 200 Bearing 201 Outer ring (stationary side member )
202 Inner ring (rotary member)
S1 sliding part

Claims (2)

  A slinger composed of a sleeve attached to the outer periphery of the rotating side member and a flange developed from one end in the axial direction thereof; a pulsar ring molded from a magnetic rubber material, multipolarly magnetized, and integrally joined to the outer surface of the flange; A thrust strip provided on the stationary member and slidably in close contact with the inner surface of the flange, the inner surface of the flange at a position on the inner peripheral side of the sliding portion with the thrust strip, A bead continuous in the circumferential direction is provided, and this bead is a part of the magnetic rubber material continuous with the inner peripheral portion of the pulsar ring through a plurality of small holes formed in the flange at predetermined intervals in the circumferential direction. A sealing device with a magnetic encoder, characterized by comprising:   The outer peripheral end of the pulsar ring extends through the outer peripheral edge of the flange of the slinger so as to go around to the outer peripheral side of the sliding portion with the thrust strip on the inner surface of the flange. A sealing device with a magnetic encoder according to 1.

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