JP2011099464A - Bearing seal for wheel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bearing seal for a wheel improved in sealing performance by preventing the intrusion of muddy water into a seal and capable of reducing torque by suppressing an increase of the sliding resistance of the seal even if muddy water intrudes and is accumulated. <P>SOLUTION: A magnetic encoder 14 is formed with a wraparound part 14a covering an outer diameter part of a standing plate 11b of a slinger 11, and a seal member 13 is adhered to an outer surface of an end of a fitting part 12a of a core metal 12 by wrapping around the outer surface. An inner diameter surface of an opening end 15 of the seal member 13 is formed into a tapered surface at an inclination angle &alpha; of 5-20&deg; toward the outer diameter side, and an inner diameter part d2 of the tapered surface and the outer diameter d1 of the wraparound part 14a face each other through a radial gap set in a range of 0.2-0.3 mm to constitute a labyrinth seal 16. By this, the muddy water resistant performance of the seal 7 is improved, and even if muddy water intrudes into the seal 7, the muddy water is easily discharged by a centrifugal force, and the intrusion of the muddy water into a bearing space can be effectively prevented. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a wheel bearing seal composed of a pack seal. More specifically, the seal seal is improved by preventing intrusion of muddy water into the seal and, for example, even if muddy water enters and accumulates. The present invention relates to a wheel bearing seal in which an increase in dynamic resistance is suppressed to reduce torque.

  2. Description of the Related Art Conventionally, a wheel bearing device for supporting a wheel of an automobile or the like supports a hub wheel for mounting a wheel rotatably via a double row rolling bearing, and includes a drive wheel and a driven wheel. For structural reasons, an inner ring rotation method is generally used for driving wheels, and an inner ring rotation method and an outer ring rotation method are generally used for driven wheels. Further, the wheel bearing device has a structure called a first generation in which a wheel bearing composed of a double row angular ball bearing or the like is fitted between a knuckle and a hub wheel constituting a suspension device. Second generation structure in which body mounting flange or wheel mounting flange is formed directly on the outer periphery of the member, third generation structure in which one inner rolling surface is directly formed on the outer periphery of the hub wheel, or hub wheel, etc. It is roughly classified into a fourth generation structure in which the inner rolling surface is directly formed on the outer periphery of the outer joint member of the speed universal joint.

  These bearing openings are fitted with seals to prevent leakage of grease sealed inside the bearings and to prevent intrusion of rainwater or dust from the outside. In recent years, the torque of bearings has been reduced to improve the fuel efficiency of automobiles. Of the rotational torque of the bearing portion, the rotational torque of the seal is dominant. That is, the sliding resistance of the seal is larger than the rolling resistance, and the ratio of the sliding resistance of the seal to the rotational torque is high. Further reduction in torque is required for the seal of the wheel bearing device. Moreover, when the bearing damage situation of a market recovery item is verified, the damage by seal failure occupies more than the original bearing life such as peeling. Therefore, the bearing life can be reliably improved by enhancing the sealing performance and durability of the seal.

  Conventionally, various wheel bearing seals having improved sealing performance have been proposed. A typical example of such a wheel bearing seal is shown in FIG. The seal 50 includes a cored bar 52 fitted to the inner peripheral surface of the end portion of the outer ring 51, a slinger 54 fitted to the outer peripheral surface of the end portion of the inner ring 53, and adhesively fixed to the cored bar 52 and slid on the slinger 54. And a sealing member 55 in contact therewith.

  The core metal 52 includes an outer diameter side cylindrical portion 52a that is fitted and fixed to the inner peripheral surface of the outer ring 51, and an inner annular portion 52b that extends radially inward from the axial inner end edge of the outer diameter side cylindrical portion 52a. Are formed in a substantially L-shaped cross section. On the other hand, the slinger 54 has an inner cylindrical portion 54a that is externally fitted and fixed to the outer peripheral surface of the inner ring 53, and an outer annular portion 54b that extends radially outward from the axial outer end edge of the inner cylindrical portion 54a. The cross section is substantially L-shaped.

  The seal member 55 is formed of synthetic rubber or the like, and has an axial lip 55a that is in sliding contact with the outer ring portion 54b of the slinger 54 in the axial direction, a radial lip 55b that is in sliding contact with the inner diameter side cylindrical portion 54a, and a grease. A slip 55c is provided. An ABS magnetic encoder 56 is fixed to the outer ring portion 54b of the slinger 54 by bonding or the like.

  Here, on the inner side surface in the axial direction of the outer annular portion 54b of the slinger 54, a step portion 57 is formed at a radially outer portion from the sliding contact position in the axial direction of the axial lip 55a. A magnetic encoder 56 is formed continuously with 57a. As described above, the axial lip 55a and the slinger 54 are formed such that the radially outer portion of the axial lip 55a is positioned more outward in the axial direction than the slidable contact position by the step 57 with respect to the axial lip 55a. Foreign matter such as muddy water is difficult to adhere to the slinger 54 in sliding contact with the vicinity of the tip of the lip 55a and the axial lip 55a.

  Further, even if foreign matter such as muddy water adheres, contact with mud at portions other than the sliding contact portion of the axial lip 55a is eliminated, so that high sealing performance can be maintained and low friction of the axial lip 55a is maintained. And low wear can be achieved (for example, see Patent Document 1).

  Further, a seal shown in FIG. 7 is known as a seal that effectively prevents muddy water from entering the bearing space. The seal 58 includes a seal member 59 attached to the outer member side and a slinger 60 attached to the inner member side.

  The seal member 59 includes a core 61 composed of a cylindrical portion 61a fitted on the inner peripheral surface of the end of the outer member, and an annular portion 61b bent at a right angle from the axial inner end of the cylindrical portion 61a. The rubber member 62 is vulcanized and bonded to the metal core 61.

  The slinger 60 is externally fitted to the outer diameter surface on the inner member side, and is bent at a right angle from the axial outer end of the cylindrical portion 60a, and the tip is between the rubber member 62 of the seal member 59. And an annular portion 60b forming a radial clearance 63, which is a magnetic encoder of a rotation sensor on the outer surface of the annular portion 60b, and magnetic rubber 64 magnetized on a plurality of magnetic poles in the circumferential direction is vulcanized and bonded. It is fixed with. The rubber member 62 of the seal member 59 is formed with two seal lips 62a and 62b slidably contacting the annular portion 60b of the slinger 60 and one seal lip 62c slidably contacting the cylindrical portion 60a.

  Here, the magnetic rubber 64 fixed to the outer surface of the annular portion 60b of the slinger 60 is formed so as to wrap around from the front end of the annular portion 60b to the inner surface side. A radial clearance 63 is formed between the magnetic rubber 64 and the rubber member 62 of the seal member 59 so as to incline radially outward in the radial direction. The inclination angle θ is 25 to 45 °. As a result, the length of the radial clearance 63 serving as the labyrinth clearance is increased, and the muddy water that has entered from the radial clearance 63 is easily discharged by the centrifugal force associated with the rotation of the wheel, thereby preventing the muddy water from entering the bearing space. It can prevent effectively (for example, refer patent document 2).

JP 2007-032640 A JP 2007-285499 A

  However, in the conventional seal 50 of the conventional (Patent Document 1), a step portion 57 is formed on the inner side surface in the axial direction of the outer annular portion 54b of the slinger 54, and is continuous with the axial side surface 57a of the step portion 57. Although the magnetic encoder 56 is fixed by bonding, the magnetic encoder 56 may be peeled off because the magnetic encoder 56 does not wrap around to the axial side surface 57a of the stepped portion 57, and the adhesive force is sufficiently secured. Therefore, the thickness of the slinger 54 is inevitably increased.

  On the other hand, in the seal 58 of the latter (Patent Document 2), although the length of the radial clearance 63 serving as the labyrinth clearance can be increased to effectively prevent the intrusion of muddy water, the muddy water that has entered once stops the vehicle. When fixed inside, the tip of the seal lip 62a is in sliding contact with the fixed muddy water, which may increase torque and wear.

  The present invention has been made in view of such a conventional problem, and prevents muddy water from entering the seal to improve the sealing performance.For example, even if muddy water enters and accumulates, An object of the present invention is to provide a wheel bearing seal in which an increase in sliding resistance is suppressed to reduce torque.

  In order to achieve such an object, the invention according to claim 1 of the present invention includes an outer member in which a double row outer rolling surface is integrally formed on the inner periphery, and a double row rolling member on the outer member. A wheel bearing seal that is inserted through a moving body and attached to an opening between the inner member having a double-row inner rolling surface on the outer periphery, and an annular seal plate disposed opposite to each other It is composed of a pack seal made of a slinger, and the seal plate includes a core metal pressed into the inner periphery of the end of the outer member, and a seal member integrally joined to the core metal by vulcanization adhesion, The seal member integrally includes a side lip extending obliquely outward in the radial direction and a grease lip extending inclined toward the inner side of the bearing, and the slinger is formed in a substantially L-shaped cross section. Cylindrical part press-fitted to the outer periphery of the end of the side member, and radial direction from this cylindrical part The magnetic encoder is integrally joined to the inner side surface of the standing plate portion by vulcanization adhesion, and the side lip is connected to the standing plate portion via a predetermined axial shimiro. In a wheel bearing seal that is slidably contacted and the grease lip is slidably contacted to the cylindrical portion via a predetermined radial squeeze, it wraps around the magnetic encoder so as to cover the outer diameter portion of the standing plate portion of the slinger. And the seal member wraps around and adheres to the outer surface of the end portion of the fitting portion of the core metal, and the inner diameter surface of the opening end portion of the seal member is predetermined toward the outer diameter side. A labyrinth seal is formed by confronting this inner diameter with the outer diameter of the wraparound portion through a slight radial clearance.

  As described above, the wheel bearing seal mounted in the opening of the annular space formed between the inner member and the outer member is a pack seal composed of an annular seal plate and a slinger arranged to face each other. The seal plate includes a mandrel that is press-fitted into the inner periphery of the end of the outer member, and a seal member that is integrally joined to the mandrel by vulcanization adhesion. A cylinder having a side lip extending incline and a grease lip extending incline toward the bearing inward side, and a slinger formed in a substantially L-shaped cross section and press-fitted into the outer periphery of the end of the inner member And a standing plate portion extending radially outward from the cylindrical portion, and a magnetic encoder is integrally joined to the inner side surface of the standing plate portion by vulcanization bonding, and a side lip is attached to the standing plate portion. Is in sliding contact with the specified axial direction In the wheel bearing seal in which the grease lip is slidably contacted with the cylindrical portion through a predetermined radial shimiro, the magnetic encoder has a wraparound portion so as to cover the outer diameter portion of the standing plate portion of the slinger, The seal member wraps around and adheres to the outer surface of the end portion of the fitting portion of the metal core, and the inner diameter surface of the opening end portion of the seal member is formed into a tapered surface having a predetermined inclination angle toward the outer diameter side. Since the inner diameter and the outer diameter of the wrap-around part face each other through a slight radial clearance, a labyrinth seal is constructed, so that the muddy water resistance of the seal is improved and muddy water enters the seal from the labyrinth seal. Even if it enters, it is easily discharged by the centrifugal force accompanying the rotation of the wheel, and muddy water can be effectively prevented from entering the bearing space.

  Further, as in the invention described in claim 2, the radial clearance between the opening end portion of the seal member and the wraparound portion of the magnetic encoder is set in a range of 0.2 to 0.3 mm (diameter value). Thus, the muddy water resistance of the seal can be improved.

  Further, as in the invention described in claim 3, if the inclination angle of the inner diameter surface of the opening end portion of the seal member is set in a range of 5 to 20 °, muddy water has entered the seal from the labyrinth seal. However, it is easily discharged by the centrifugal force accompanying the rotation of the wheel, and the muddy water resistance of the seal can be improved.

  If the straight part of the wraparound part of the magnetic encoder extends to the extension line of the tip of the side lip as in the invention described in claim 4, the joining force of the magnetic encoder is increased, and the length Prevents peeling from the standing plate part over a period of time, and the muddy water that has entered from the labyrinth seal can be easily discharged along the outer surface of the side lip by centrifugal force, for example, muddy water accumulates and adheres Even if it does, since contact with mud in parts other than the tip sliding contact part of a side lip is lost, increase in sliding resistance of a seal can be controlled and torque can be reduced.

  Further, as in the invention described in claim 5, a step portion is formed on the outer diameter portion of the standing plate portion of the slinger, and a wrap portion of the magnetic encoder is formed on the step portion. If the end surface is set to be substantially flush with the outer side surface of the upright plate portion, the muddy water entering from the labyrinth seal can be easily discharged along the outer surface of the side lip by centrifugal force. The muddy water resistance can be further improved.

  Further, as in the invention described in claim 6, the depth of the step portion of the standing plate portion is set in a range of 0.2 to 0.5 mm, and the width of the step portion is 0.2 to 0. If it is set in the range of .6 mm, the magnetic encoder can be vulcanized and bonded, and the strength of the standing plate portion can be secured without making the slinger plate thickness unnecessarily thick.

  Further, as in the invention described in claim 7, the tapered surface of the inner diameter surface of the opening end is formed only on the inner diameter surface located on the road surface side, and is configured as a discharge port having a predetermined angle range. If the inner surface of the cylinder is formed in a cylindrical shape, even if muddy water enters the seal from the labyrinth seal, the muddy water hangs down along the outer side lip when the wheel stops, and the open end on the road surface side Therefore, the muddy water can be easily discharged through the discharge port, and the muddy water resistance of the seal can be further improved.

  Further, as in the invention described in claim 8, if the formation angle of the discharge port is set in the range of 30 to 75 °, muddy water can be effectively discharged, and the seal resistance is improved. Muddy water performance can be improved.

  Further, as in the ninth aspect of the invention, the seal member includes first and second side lips extending obliquely outward in the radial direction, and among these first and second side lips. If the shim of the first side lip formed on the outer diameter side is set to be slightly larger than the shim of the inner side lip, the seal sliding torque is suppressed and the first side lip is worn. Can maintain the desired hermeticity.

  Further, as in the invention described in claim 10, the seal member may be formed of hydrogenated acrylonitrile-butadiene rubber.

  The wheel bearing seal according to the present invention includes an outer member in which a double row outer rolling surface is integrally formed on the inner periphery, and the outer member is inserted into the outer member via a double row rolling element. A bearing seal for a wheel mounted in an opening between the inner member having a double row inner rolling surface, and is constituted by a pack seal composed of an annular seal plate and a slinger arranged to face each other, The seal plate includes a metal core that is press-fitted into the inner periphery of the end of the outer member, and a seal member that is integrally joined to the metal core by vulcanization adhesion, and the seal member is radially outward. A slanting side lip and a grease lip extending slantingly inwardly of the bearing are integrally formed, and the slinger is formed in a substantially L-shaped cross section and is press-fitted into the outer periphery of the end of the inner member. A cylindrical portion and a standing plate portion extending radially outward from the cylindrical portion. A magnetic encoder is integrally joined to the inner side surface of the upright plate portion by vulcanization adhesion, the side lip is slidably contacted with the upright plate portion via a predetermined axial direction shimiro, and the grease lip is attached to the cylindrical portion. In the wheel bearing seal slidably contacted via a predetermined radial direction shimiro, the magnetic encoder is formed with a wraparound portion so as to cover the outer diameter portion of the standing plate portion of the slinger, and the seal member The inner end surface of the end portion of the fitting portion of the metal core is fixed, and the inner diameter surface of the opening end portion of the seal member is formed into a tapered surface having a predetermined inclination angle toward the outer diameter side, This inner diameter and the outer diameter of the wrap-around part face each other through a slight radial clearance, and a labyrinth seal is constructed, so that the muddy water resistance of the seal is improved and the labyrinth seal enters the seal. Even if water intrudes, is easily discharged by a centrifugal force accompanying the rotation of the wheel, it is possible to prevent the intrusion of muddy water into the bearing space effectively.

It is a longitudinal cross-sectional view which shows the wheel bearing with which the wheel bearing seal which concerns on this invention was mounted | worn. It is sectional drawing which shows the seal | sticker which concerns on this invention. (A) is sectional drawing which shows the modification of the seal | sticker of FIG. 2, (b) is an enlarged view of (a). (A) is sectional drawing which shows the modification of the seal | sticker of FIG. 3, (b) is an enlarged view of (a). (A) is a longitudinal cross-sectional view which shows the other modification of the seal | sticker of FIG. 2, (b) is a front view of (a). It is sectional drawing which shows the conventional seal | sticker. It is sectional drawing which shows another conventional seal | sticker.

  An outer member in which a double row outer rolling surface is integrally formed on the inner periphery, and an inner member inserted into the outer member via a double row rolling element and having a double row inner rolling surface on the outer periphery. A bearing seal for a wheel mounted in an opening between the outer member and a pack seal composed of an annular seal plate and a slinger arranged opposite to each other, and the seal plate of the outer member A metal core that is press-fitted into the inner periphery of the end portion, and a seal member that is integrally bonded to the metal core by vulcanization adhesion. The seal member extends in a radially outwardly inclined manner; a bearing lip; A grease lip that extends in an inclined manner toward the side, and the slinger is formed in a substantially L-shaped cross-section, and is press-fitted into the outer periphery of the end of the inner member, and the radial direction from the cylindrical portion A standing plate portion extending outward, on the inner side surface of the standing plate portion A pneumatic encoder is integrally joined by vulcanization adhesion, the side lip is slidably contacted with the vertical plate portion via a predetermined axial squeeze, and the grease lip is slid with respect to the cylindrical portion via a predetermined radial shimeshiro. In the wheel bearing seal in contact, the magnetic encoder is formed with a wraparound portion so as to cover an outer diameter portion of the standing plate portion of the slinger, and the seal member is an end of the fitting portion of the cored bar. The inner diameter surface of the opening end portion of the seal member is formed into a tapered surface having an inclination angle of 5 to 20 degrees toward the outer diameter side, the inner diameter and the wraparound portion. The labyrinth seal is configured to face each other through a radial clearance set in a range of 0.2 to 0.3 mm (diameter value).

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
1 is a longitudinal sectional view showing a wheel bearing equipped with a seal according to the present invention, FIG. 2 is a sectional view showing the seal according to the present invention, and FIG. 3A is a modification of the seal of FIG. FIG. 4B is an enlarged view of FIG. 4A, FIG. 4A is a sectional view showing a modification of FIG. 3, FIG. 4B is an enlarged view of FIG. ) Is a longitudinal sectional view showing another modification of the seal of FIG. 2, and (b) is a front view of (a). In the following description, the side closer to the outer side of the vehicle when assembled to the vehicle is referred to as the outer side (left side in FIG. 1), and the side closer to the center is referred to as the inner side (right side in FIG. 1).

  The wheel bearing 1 shown in FIG. 1 is referred to as the first generation, and an outer member 2 in which double row outer rolling surfaces 2a and 2a are integrally formed on the inner periphery, and the double row outer rolling on the outer periphery. A pair of inner rings 3, 3 each having an inner rolling surface 3a opposite to the surfaces 2a, 2a, double-row rolling elements (balls) 4, 4 accommodated between both rolling surfaces, Retainers 5 and 5 that hold the moving bodies 4 and 4 in a freely rollable manner, and seals 6 and 7 that are attached to openings in an annular space formed between the outer member 2 and the pair of inner rings 3 and 3, It has.

  The outer member 2 is made of high carbon chromium bearing steel such as SUJ2 (JIS G 4805) or carburized steel. In the case of high carbon chromium bearing steel, after quenching at 820 to 860 ° C., it is tempered at 160 to 200 ° C. and cured to the core in the range of 58 to 64 HRC. In the case of carburized steel, the surface is hardened in the range of 58 to 64 HRC. On the other hand, the inner ring 3 is also made of high carbon chrome bearing steel such as SUJ2 or carburized steel, like the outer member 2, and in the case of high carbon chrome bearing steel, the core is hardened in the range of 58 to 64 HRC, and carburized steel. In the case of, the surface is cured in the range of 58 to 64 HRC. Moreover, the rolling element 4 consists of high carbon chromium bearing steel, such as SUJ2, and is hardened in the range of 62-67 HRC to the core part by the quenching quenching.

  This wheel bearing 1 is set in a state where the small diameter side (front side) end faces 3b and 3b of the pair of inner rings 3 and 3 are abutted, and constitutes a so-called back-to-back type double row angular ball bearing. . Further, the seals 6 and 7 prevent leakage of the lubricating grease sealed inside the bearing and intrusion of rainwater, dust, and the like from the outside into the bearing.

  The seal 6 on the outer side of the seals 6, 7 is a cored bar 8 press-fitted through a predetermined shimiro to the inner periphery of the outer side end portion of the outer member 2 serving as a fixed side member. It is composed of an integrated seal composed of a joined seal member 9.

  Further, as shown in an enlarged view in FIG. 2, the inner-side seal 7 is constituted by a so-called pack seal, which is a composite seal composed of an annular seal plate 10 and a slinger 11 which are arranged to face each other. The seal plate 10 includes a cored bar 12 attached to the outer member 2 and a seal member 13 integrally joined to the cored bar 12 by vulcanization adhesion.

  The core metal 12 is formed by pressing from a steel plate having rust prevention ability such as an austenitic stainless steel plate (JIS standard SUS304 type) or a rust-proof cold rolled steel plate (JIS standard SPCC type). A cylindrical fitting portion 12a that is formed in a substantially L-shaped cross section, is press-fitted into the outer member 2, has a slightly reduced diameter at the end, and is formed radially inward from the fitting portion 12a. And an inner diameter portion 12b.

  The seal member 13 is made of a synthetic rubber such as NBR (acrylonitrile-butadiene rubber), and extends first and second side lips 13a and 13b extending obliquely outward in the radial direction, and the first and second side lips. On the inner diameter side of 13a, 13b, there is a grease lip 13c extending inclinedly toward the bearing inward side. In addition to NBR, the material of the seal member 13 includes, for example, HNBR (hydrogenated acrylonitrile-butadiene rubber), EPM, EPDM (ethylene / propylene rubber), etc., which have excellent heat resistance, heat resistance and chemical resistance. Examples thereof include ACM (polyacrylic rubber), FKM (fluororubber), and silicon rubber, which are excellent in properties.

  On the other hand, the slinger 11 has a substantially L-shaped cross section, and includes a cylindrical portion 11a that is press-fitted into the outer diameter of the inner ring 3, and a standing plate portion 11b that extends radially outward from the cylindrical portion 11a. The first and second side lips 13a and 13b of the seal member 13 are slidably contacted to the upright plate portion 11b via a predetermined axial squeeze, and the grease lip 13c is slid to the cylindrical portion 11a in a predetermined radial direction. It is slid through. Of the first and second side lips 13a and 13b, the first side lip 13a formed on the outer diameter side is set slightly larger than the inner side side lip 13b. Thereby, a seal sliding torque is suppressed and desired sealing performance can be maintained even if the first side lip 13a is worn. Further, the magnetic encoder 14 is integrally joined to the inner side surface of the standing plate portion 11b by vulcanization adhesion. This magnetic encoder 14 constitutes a rotary encoder in which magnetic powder is mixed in an elastomer and magnetic poles N and S are alternately magnetized at equal intervals in the circumferential direction.

  In addition, although the 1st generation wheel bearing comprised by the double row angular contact ball bearing which used the rolling element 4 as a ball | bowl was illustrated here, it is not restricted to this, The double row tapered roller bearing which uses a tapered roller for a rolling element It may consist of. Moreover, the 2nd-3rd generation structure may be sufficient.

  Here, the seal member 13 wraps around and is fixed to the outer surface of the end portion of the fitting portion 12 a of the core metal 12, thereby improving the airtightness of the fitting portion with the outer member 2. The inner diameter surface of the open end 15 of the seal member 13 is formed into a tapered surface having a predetermined inclination angle α toward the outer diameter side. Further, the magnetic encoder 14 is formed with a wrap-around portion 14 a so as to cover the outer diameter portion of the standing plate portion 11 b of the slinger 11. The outer diameter d1 and the inner diameter d2 of the opening end 15 of the seal member 13 are opposed to each other through a slight radial clearance δ, so that the labyrinth seal 16 is configured. The inclination angle α of the opening end 15 is set in the range of 5 to 20 °, and the radial clearance δ (= d2−d1) is set in the range of 0.2 to 0.3 mm. As a result, the muddy water resistance of the seal 7 is improved, and even if muddy water enters the seal 7 from the labyrinth seal 16, it is easily discharged by the centrifugal force accompanying the rotation of the wheel, and muddy water enters the bearing space. It can be effectively prevented.

  In addition, when the inclination angle α of the opening end portion 15 exceeds 20 °, the muddy water easily enters, and when the inclination angle α is less than 5 °, it is difficult to discharge the muddy water by centrifugal force. In addition, when the radial clearance δ of the labyrinth seal 16 exceeds 0.3 mm (diameter value), the labyrinth effect decreases and the muddy water resistance decreases, and when less than 0.2 mm (diameter value), muddy water is discharged. Since it becomes difficult, it is not preferable.

  A seal 17 shown in FIG. 3A is a modification of the seal 7 described above. The seal 17 has basically the same shape as the seal 7, but the configuration of the wraparound portion 18a of the magnetic encoder 18 is different. That is, as shown in an enlarged view in (b), the straight portion of the wrap-around portion 18a of the magnetic encoder 18 extends deeply to the extended line at the tip of the side lip 13a on the outer diameter side. As a result, the joining force of the magnetic encoder 18 is increased, preventing separation from the standing plate portion 11b over a long period of time, and the muddy water that has entered from the labyrinth seal 16 along the outer surface of the side lip 13a by centrifugal force. Even if muddy water accumulates and adheres, contact with mud at portions other than the tip sliding contact portion of the side lip 13a is eliminated, so that the sliding resistance of the seal 17 is increased. It is possible to provide a wheel bearing seal that is suppressed to reduce torque.

  A seal 19 shown in FIG. 4A is a modification of the seal 17 described above. The shape of the seal 19 is basically the same as that of the seal 17, but the configuration of the outer diameter portion of the standing plate portion 20 b of the slinger 20 and the wraparound straight portion of the magnetic encoder 21 are different. That is, the slinger 20 includes a cylindrical portion 11a fitted to the outer diameter of an inner ring (not shown) and a standing plate portion 20a extending radially outward from the cylindrical portion 11a. A step portion 22 is formed in the diameter portion. As shown in an enlarged view (b), a wraparound portion 21a of the magnetic encoder 21 is formed in the step portion 22, and its end surface is set substantially flush with the outer side surface of the upright plate portion 20a. And the wrap-around part 21a is arrange | positioned on the extension line | wire of the front-end | tip of the side lip 13a on the outer diameter side. Thereby, the muddy water that has entered from the labyrinth seal 16 can be easily discharged along the outer surface of the side lip 13a by centrifugal force. For example, even if muddy water accumulates and adheres, the tip sliding contact of the side lip 13a occurs. Since there is no contact with mud in parts other than the part, an increase in sliding resistance of the seal 19 can be suppressed. Here, the abbreviation of “substantially the same” includes the degree of error of each member and the error at the time of joining, specifically about ± 0.1 mm.

  In addition, the depth E of the step part 22 of the standing plate part 20a is set in the range of 0.2 to 0.5 mm, and the width F is set in the range of 0.2 to 0.6 mm. Thereby, the intensity | strength of the standing board part 20a is securable without making the board | plate thickness of the slinger 20 unnecessarily thick.

  A seal 23 shown in FIG. 5A is another modification of the seal 7 described above. The seal 23 is composed of a pack seal composed of an annular seal plate 24 and a slinger 11 which are arranged to face each other. The seal plate 24 includes a cored bar 12 attached to an outer member (not shown), and a seal member 25 integrally joined to the cored bar 12 by vulcanization adhesion.

  Of the inner diameter surface of the opening end portion 26 of the seal member 25, only the inner diameter surface in the range of the predetermined angle β located on the road surface side (lower side in the figure) is a taper having a predetermined inclination angle α toward the outer diameter side. The other inner diameter surface is formed in a cylindrical shape. As a result, even if muddy water enters the seal 23 from the labyrinth seal 16 due to centrifugal force accompanying the rotation of the wheel, the muddy water moves downward along the outer side lip 13a when the wheel stops. Since a discharge port 26a having a tapered surface is formed at the open end portion 26 on the road surface side, the muddy water can be easily discharged through the discharge port 26a, and the muddy water resistance performance of the seal 23 is further improved. Can do.

  Here, the formation angle β of the discharge port 26a on the road surface side is preferably in the range of 30 to 75 °. This is because when β is less than 30 °, the discharge effect is reduced, and when β exceeds 75 °, the muddy water resistance of the seal 23 is deteriorated.

  The embodiment of the present invention has been described above, but the present invention is not limited to such an embodiment, and is merely an example, and various modifications can be made without departing from the scope of the present invention. Of course, the scope of the present invention is indicated by the description of the scope of claims, and further, the equivalent meanings described in the scope of claims and all modifications within the scope of the scope of the present invention are included. Including.

  The wheel bearing seal according to the present invention can be applied to a pack seal composed of an annular seal plate and a slinger arranged to face each other.

DESCRIPTION OF SYMBOLS 1 Wheel bearing 2 Outer member 2a Outer rolling surface 3 Inner ring 3a Inner rolling surface 3b Small diameter side end surface 4 Rolling body 5 Cage 6, 7, 17, 19, 23 Seal 8, 12 Core metal 9, 13, 25 Seal members 10, 24 Seal plates 11, 20 Slinger 11a Cylindrical portion 11b, 20a Standing plate portion 12a Fitting portion 12b Inner diameter portion 13a First side lip 13b Second side lip 13c Grease lips 14, 18, 21 Magnetic encoder 14a , 18a, 21a wraparound portion 15, 26 opening end portion 16 labyrinth seal 22 step portion 26a discharge port 50, 58 seal 51 outer ring 52 core metal 52a outer diameter side cylindrical portion 52b inner ring portion 53 inner ring 54 slinger 54a inner diameter cylindrical portion 54b Outer ring portion 55 Seal member 55a Axial lip 55b Radial lip 55c Grease lip 56 Magnetic encoder Order 57 Step 57a Axial side surface 59 of the step part Seal member 60 Slinger 60a Cylindrical part 60b Ring part 61 Core bar 61a Cylindrical part 61b Ring part 62 Rubber members 62a, 62b Axial lip 62c Grease lip 63 Radial clearance 64 Magnetic Rubber d1 Magnetic encoder outer diameter d2 Open end inner diameter θ Inclination angle α Open end inner diameter surface tilt angle β Tapered surface formation angle

Claims (10)

An outer member in which a double row outer rolling surface is integrally formed on the inner periphery, and an inner member inserted into the outer member via a double row rolling element and having a double row inner rolling surface on the outer periphery. A wheel bearing seal mounted in an opening between the side member,
It is composed of a pack seal composed of an annular seal plate and a slinger arranged to face each other, and the seal plate is integrated with a core metal pressed into the inner periphery of the end of the outer member by vulcanization adhesion. And a sealing member joined to
The seal member integrally has a side lip extending inclined outward in the radial direction and a grease lip extending inclined toward the bearing inward side,
The slinger is formed in a substantially L-shaped cross section, and has a cylindrical portion that is press-fitted into the outer periphery of the end portion of the inner member, and a standing plate portion that extends radially outward from the cylindrical portion,
A magnetic encoder is integrally joined to the inner side surface of the upright plate portion by vulcanization adhesion, the side lip is slidably contacted with the upright plate portion via a predetermined axial direction shimiro, and the grease lip is attached to the cylindrical portion. In the wheel bearing seal that is slidably contacted through a predetermined radial shimeshiro,
In the magnetic encoder, a wraparound portion is formed so as to cover an outer diameter portion of the standing plate portion of the slinger, and the seal member wraps around and adheres to the outer surface of the end portion of the fitting portion of the cored bar. The inner diameter surface of the opening end portion of the seal member is formed into a tapered surface having a predetermined inclination angle toward the outer diameter side, and the inner diameter and the outer diameter of the wraparound portion are passed through a slight radial clearance. A bearing seal for wheels, characterized in that a labyrinth seal is formed.   The wheel bearing seal according to claim 1, wherein a radial clearance between an opening end portion of the seal member and a wraparound portion of the magnetic encoder is set in a range of 0.2 to 0.3 mm (diameter value).   The wheel bearing seal according to claim 1 or 2, wherein an inclination angle of an inner diameter surface of an opening end portion of the seal member is set in a range of 5 to 20 °.   The wheel bearing seal according to claim 1 or 2, wherein a straight portion of a wraparound portion of the magnetic encoder extends to an extension line of a tip of the side lip.   A step portion is formed in the outer diameter portion of the sling plate standing plate portion, and a wraparound portion of the magnetic encoder is formed in the step portion, and an end surface of the wraparound portion is substantially the same as the outer side surface of the standing plate portion. The wheel bearing seal according to claim 1, wherein the wheel bearing seal is set flush.   The depth of the step portion of the upright plate portion is set in a range of 0.2 to 0.5 mm, and the width of the step portion is set in a range of 0.2 to 0.6 mm. Wheel bearing seal as described.   The tapered surface of the inner diameter surface of the opening end is formed only on the inner diameter surface located on the road surface side, is configured as a discharge port having a predetermined angle range, and the other inner diameter surface is formed in a cylindrical shape. A bearing seal for a wheel according to any one of 1 to 3.   The wheel bearing seal according to claim 7, wherein a formation angle of the discharge port is set in a range of 30 to 75 °.   The seal member includes first and second side lips extending obliquely outward in the radial direction, and the first side lip formed on the outer diameter side of the first and second side lips. The wheel bearing seal according to any one of claims 1 to 3, wherein the shimeshiro is set slightly larger than the shimeshiro of the side lip on the inner diameter side.   The wheel bearing seal according to claim 9, wherein the seal member is formed of hydrogenated acrylonitrile-butadiene rubber.

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