JP6483460B2 - SEALING DEVICE AND WHEEL BEARING DEVICE HAVING THE SAME - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a sealing device for sealing a bearing space, and more particularly to a sealing device having sufficient sealing performance for a long time even in an environment where a large amount of foreign matter such as rainwater and muddy water exists, and a wheel bearing device including the same. It is.

  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.

  In such a wheel bearing device, the grease sealed inside the bearing is prevented from leaking, and since it is in an environment where it is directly exposed to rainwater, muddy water, etc., the rainwater, muddy water, etc. are firmly prevented from entering the bearing. A sealing device having a good sealing property is mounted. In recent years, there has been a demand for longer life in this type of wheel bearing device used in such a severe environment. Of the sealing devices, the sealing member having a particularly high sealing performance is attached to an outer member serving as a fixed member, and the sealing lip is slidably contacted with a slinger attached to the inner member. So-called pack seals are commonly used.

  Conventionally, various types of sealing devices for wheel bearings with improved sealing performance have been proposed. A typical example of such a sealing device is shown in FIG. In the sealing device 50, an annular slinger 51 is provided with an encoder 52 formed on the outer peripheral side thereof, and the slinger 51 and an inner peripheral surface of a core metal 53 facing the inner peripheral side of the slinger 51 are sealed. An annular seal body 55 configured by vulcanizing and bonding the material 54 is disposed so as to be rotatable about a rotation axis.

  In the seal body 55, the side lip 54a integrally formed by the seal material 54 extends in a direction transverse to the space between the seal body 55 and the slinger 51, and spreads toward the labyrinth portion Lp in a conical shape. Inclined and extended.

  An annular first swivel portion 56 formed by turning the encoder material to the inner peripheral side of the slinger 51 so as to cover the radially extending end 51 t of the slinger 51, and the seal material 54 in the axial direction of the core metal 53. An axial second labyrinth 1Lp extending in the axial direction between the slinger 51 and the seal body 55 is formed by an annular second swivel portion 57 that is formed so as to cover the end portion 53t. An annular labyrinth portion Lp having a radial labyrinth 2Lp continuously extending in the radial direction from the directional labyrinth 1Lp is configured, and the radial labyrinth 2Lp is configured in a positional relationship that avoids a contact portion of the side lip with the slinger 51 Has been.

  As described above, the labyrinth portion Lp configured between the slinger 51 and the seal body 55 is extended, so that foreign matter such as earth and sand and water can be prevented from entering, and foreign matter such as earth and sand can enter. It is possible to guide the foreign substance from the sliding position in a direction avoiding the sliding position (see, for example, Patent Document 1).

JP 2012-229663 A

  However, in such a conventional sealing device 50, foreign matter such as earth and sand is difficult to enter. However, once foreign matter such as earth and water enters the sealing device 50, the sealing material 54 and the encoder 52 are not connected. There existed a subject that it stayed in the circumference | surroundings of 1 rounding part 56, and it was hard to discharge | emit outside.

  The present invention has been made in view of such circumstances, and in the pack seal, when muddy water or the like enters the sealing device, it rotates on the inlet side and the inner side of the labyrinth clearance of the opposing annular seal plate and slinger. It is designed to generate a pressure difference due to the pressure difference, and a structure that facilitates the discharge of muddy water due to the pressure difference is conceived. A sealing device that maintains high sealing performance and a wheel bearing device equipped with the sealing device are provided. It is intended to provide.

  In order to achieve the object, the invention according to claim 1 of the present invention is composed of an annular seal plate and a slinger arranged to face each other, and the seal plate is press-fitted into the end of the outer member. And a sealing member integrally joined to the cored bar by vulcanization adhesion, and the slinger is provided with a cored part formed of an inner diameter part extending radially inward from the end of the fitted part. A cylindrical portion that is press-fitted into the inner member, and an upright plate portion that extends radially outward from the cylindrical portion, and the seal member is joined to the inner diameter of the fitting portion of the metal core; In the sealing device having a side lip formed to be inclined radially outward and slidingly contact the standing plate portion of the slinger, the extending portion extends from the outer end portion of the standing plate portion of the slinger to the bearing inward side. A diameter between the extension portion and the opening of the seal member. An axial labyrinth is formed between the orientation labyrinth, the end surface of the extension portion, and the seal member, and at least one of the outer diameter surface of the extension portion and the inner diameter surface of the opening portion of the seal member is The radial labyrinth is formed in a tapered surface and has a spire shape, and the clearance on the inlet side of the radial labyrinth is set to be larger than the labyrinth clearance on the inner side.

  In this way, it is composed of a ring seal plate and a pack seal composed of a slinger arranged to face each other, and the seal plate is press-fitted into the end of the outer member, and this fitting portion. A cylindrical portion in which a slinger is press-fitted into the inner member, and a core member made of an inner diameter portion extending radially inward from the end of the core member, and a seal member integrally bonded to the core member by vulcanization adhesion, and The seal member is provided with a standing plate portion extending radially outward from the cylindrical portion, and an opening joined to the inner diameter of the fitting portion of the cored bar, and is formed to incline radially outwardly. In a sealing device having a side lip that is in sliding contact with the upright plate portion, an extension portion extending from the outer end portion of the slinger upright plate portion to the bearing inward side is provided, and between the extended portion and the opening portion of the seal member Between the radial labyrinth and the end face of the extension and the seal member A directional labyrinth is formed, and at least one of the outer diameter surface of the extending portion and the inner diameter surface of the opening of the seal member is formed into a tapered surface, and the radial labyrinth is formed in a spire shape. Since the clearance on the inlet side is set to be larger than the labyrinth clearance on the inner side, an L-shaped labyrinth consisting of a radial labyrinth and an axial labyrinth is formed to prevent intrusion of muddy water from the outside In addition, even if muddy water or the like enters the sealing device, a pressure difference due to rotation occurs between the inlet side and the inner side of the radial labyrinth clearance, and this pressure difference causes the muddy water to flow and be easily discharged. And a sealing device capable of maintaining high sealing performance can be provided.

  Preferably, as in the second aspect of the invention, if the inner diameter of the extending portion of the slinger is formed on a tapered surface that gradually expands toward the inner side of the bearing, muddy water or the like is contained in the sealing device. The muddy water that adheres to or stays in the extension even when it enters, flows along the inner diameter surface of the extension as it rotates, and the pressure difference between the inlet side and the inner side of the labyrinth clearance Combined with the effect of, the muddy water flows and becomes more easily discharged.

  Further, as in the invention according to claim 3, the extending portion is joined from the side surface of the standing plate portion of the slinger to the outer end portion, and magnetic powder is mixed into the elastomer so that the circumferential direction of the side surface If magnetic poles N and S are alternately magnetized, an L-shaped labyrinth composed of a radial labyrinth and an axial labyrinth can be formed simply by extending the magnetic encoder instead of a separate member. , Cost increase can be suppressed.

  Further, as in the invention described in claim 4, if the extending portion is formed of a bent portion integrally formed from the outer end portion of the standing plate portion of the slinger, the extending portion is extended by the pressure of muddy water. The deformation of the portion can be suppressed, and the desired labyrinth clearance can be maintained.

  In addition, as in the invention described in claim 5, a stepped portion is provided at the tip of the bent portion of the slinger, and the outer diameter surface of the stepped portion is a tapered surface that gradually expands toward the bearing inner side. The magnetic encoder having the magnetic poles N and S magnetized alternately in the circumferential direction of the side surface is joined together with the magnetic material powder mixed in the elastomer from the side surface of the slinger standing plate portion to the stepped portion. If this is the case, the slinger can be shared in response to changes in specifications depending on the presence or absence of the magnetic encoder.

  In the invention according to claim 6 of the present invention, an outer member in which a double row outer rolling surface is integrally formed on the inner periphery and a wheel mounting flange for mounting a wheel on one end are integrated. A hub wheel having a small-diameter step portion extending in the axial direction on the outer periphery, and at least one inner ring fitted to the small-diameter step portion of the hub wheel. An inner member formed with opposing double-row inner rolling surfaces, a double-row rolling element housed in a freely rolling manner between the inner member and the outer member; A wheel bearing device comprising: a sealing device that seals an opening portion of an annular space formed between an outer member and an inner member; and the sealing device according to any one of claims 1 to 5. It consists of a sealing device.

  Thus, in the wheel bearing device including the sealing device that seals the opening of the annular space formed between the outer member and the inner member, the sealing device is any one of the first to fifth aspects. Because it is composed of the described sealing device, it prevents the intrusion of muddy water from the outside, and the pressure caused by the rotation on the inlet side and the inner side of the radial labyrinth clearance even if the muddy water enters the sealing device. A difference is generated, and a flow is generated in the muddy water due to the pressure difference, which can be easily discharged, and a wheel bearing device that maintains high sealing performance can be provided.

  A sealing device according to the present invention includes an annular seal plate and a slinger arranged to face each other, and the seal plate is press-fitted into an end portion of an outer member, and the fitting portion. A cylindrical portion in which the slinger is press-fitted into the inner member, and a core member made of an inner diameter portion extending radially inward from the end portion of the core member, and a seal member integrally bonded to the core member by vulcanization adhesion, And a standing plate portion extending radially outward from the cylindrical portion, and the seal member is formed to be inclined to the radially outer side with an opening joined to the inner diameter of the fitting portion of the cored bar. The sealing device having a side lip that is in sliding contact with the standing plate portion of the slinger includes an extending portion that extends inward from the outer end portion of the standing plate portion of the slinger, and the extending portion and the seal member A radial labyrinth between the opening and the end of the extension An axial labyrinth is formed between the outer circumferential surface and the sealing member, and at least one of the outer diameter surface of the extending portion and the inner diameter surface of the opening portion of the sealing member is formed into a tapered surface, and the radial labyrinth Is formed so that the clearance on the inlet side of the radial labyrinth is larger than the labyrinth clearance on the inner side, so that an L-shaped labyrinth composed of a radial labyrinth and an axial labyrinth is formed. In addition to preventing the intrusion of muddy water from the outside, even if muddy water enters the sealing device, a pressure difference due to rotation occurs between the inlet side and the inner side of the radial labyrinth clearance. A flow can be easily generated in the muddy water and discharged, and a sealing device that maintains high sealing performance can be provided.

  Further, the wheel bearing device according to the present invention integrally has an outer member in which a double row outer rolling surface is integrally formed on the inner periphery, and a wheel mounting flange for attaching the wheel to one end. A hub wheel having a small-diameter step portion extending in the axial direction on the outer periphery, and at least one inner ring fitted to the small-diameter step portion of the hub wheel, and having a plurality of outer rings facing the double-row outer rolling surface on the outer periphery. An inner member in which an inner rolling surface of the row is formed; a double row rolling element that is slidably accommodated between the rolling surfaces of the inner member and the outer member; and the outer member And a sealing device that seals an opening of an annular space formed between the inner member and the inner member, wherein the sealing device is the sealing device according to any one of claims 1 to 5. As it is composed of, it prevents muddy water from entering from the outside, and muddy water etc. Even if it enters the sealing device, a pressure difference due to rotation occurs between the inlet side and the inner side of the radial labyrinth clearance, and this pressure difference can cause the muddy water to flow and be easily discharged. A wheel bearing device to be maintained can be provided.

It is a longitudinal section showing a 1st embodiment of a wheel bearing provided with a sealing device concerning the present invention. It is a longitudinal cross-sectional view which shows one sealing device of FIG. It is a longitudinal cross-sectional view which shows the modification of the sealing device of FIG. It is a longitudinal cross-sectional view which shows the modification of the sealing device of FIG. It is a longitudinal cross-sectional view which shows the modification of the sealing device of FIG. It is a longitudinal cross-sectional view which shows 2nd Embodiment of the wheel bearing apparatus provided with the sealing device which concerns on this invention. It is a longitudinal cross-sectional view which shows one sealing device of FIG. It is a longitudinal cross-sectional view which shows the conventional sealing device.

  It is composed of a pack seal composed of an annular seal plate and a slinger, which are arranged to face each other and have an L-shaped cross section, and the seal plate is press-fitted into the inner periphery of the end of the outer member serving as the fixed member. A cylindrical fitting part, a cored bar composed of an inner diameter part extending radially inward from the end part of the fitting part, and a tip part of the fitting part integrally joined to the cored bar by vulcanization bonding A cylindrical member that is press-fitted into the outer diameter of the inner ring that serves as the rotation side member, and a vertical plate that extends radially outward from the cylindrical portion. The seal member is formed to be inclined outward in the radial direction, and is formed to be inclined inward in the radial direction on the inner diameter side of the side lip and in contact with the standing plate portion of the slinger. A formed grease lip, and a seal with The slinger stands from the outer end portion of the standing plate portion to the inside of the bearing, and wraps around and joins from the side surface of the standing plate portion to the outer end portion. An extension portion composed of a magnetic encoder having magnetic poles N and S alternately magnetized in the direction, a radial labyrinth between the extension portion and the opening of the seal member, and an end face of the extension portion, An axial labyrinth is formed between the seal member and the outer diameter surface of the extension portion and the inner diameter surface of the opening portion of the seal member are formed into a tapered surface so that the radial labyrinth is formed in a spire shape. The clearance on the inlet side of the radial labyrinth is set to be larger than the clearance on the inner side.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a longitudinal sectional view showing a first embodiment of a wheel bearing provided with a sealing device according to the present invention, FIG. 2 is a sectional view showing one sealing device of FIG. 1, and FIG. FIG. 4 is a longitudinal sectional view showing a modification of the sealing device of FIG. 3, and FIG. 5 is a longitudinal sectional view showing a modification of the sealing device of FIG. 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).

  A wheel bearing 1 shown in FIG. 1 is called a first generation used in a wheel bearing device, and is an outer member (outer ring) in which double row outer rolling surfaces 2a and 2a are integrally formed on the inner periphery. ) 2, a pair of inner races (inner members) 3, 3 formed integrally with the outer raceway 2 a, 2 a and the inner raceway 3 a facing the outer row, and between the raceways The accommodated double row rolling elements (balls) 4, 4, cages 5, 5 that hold these rolling elements 4, 4, and outer member 2 and a pair of inner rings 3, 3. And sealing devices 6 and 7 attached to the opening of the annular space formed therebetween.

  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 sealing devices 6 and 7 prevent the leakage of the lubricating grease sealed inside the bearing, and prevents rainwater, dust, and the like from entering the bearing from the outside.

  In addition, although what was comprised by the double row angular contact ball bearing which used the ball for the rolling element 4 as the wheel bearing 1 was illustrated here, not only this but the double row tapered roller which used the tapered roller for the rolling element 4 You may be comprised with the bearing.

  The sealing device 6 on the outer side of the sealing devices 6 and 7 includes a cored bar 8 that is press-fitted into the inner periphery of the outer side end portion of the outer member 2 that is a fixed side member via a predetermined shimiro, and this cored bar. 8 is integrally formed by a vulcanization adhesion, and is composed of an integral seal composed of a seal member 9 formed of synthetic rubber or the like.

  Further, the inner side sealing device 7 is a pack seal comprising an annular seal plate 10 which is disposed opposite to each other and has a substantially L-shaped cross section, and a slinger 11 having a substantially U-shaped cross section. It consists of 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.

  Here, the inner side sealing device 7 will be described with reference to FIG. The core 12 has a cross-sectional shape that is reduced by pressing from a steel plate having rust prevention ability, such as an austenitic stainless steel plate (JIS standard SUS304 type, etc.) or a rust-proof cold rolled steel plate (JIS standard SPCC type, etc.). It is formed in an L shape. As shown in an enlarged view in FIG. 2, the core metal 12 is press-fitted into the outer member 2 and has a cylindrical fitting portion 12a formed with a thin wall by slightly reducing the diameter of the end portion. And an inner diameter portion 12b extending radially inward from the portion 12a. And the sealing member 13 wraps around and joins so that the front-end | tip part of the fitting part 12a may be covered, and has comprised what is called a half metal structure. Thereby, while being able to ensure appropriate fitting force, it can prevent that muddy water etc. permeate from a fitting surface by crimping of the sealing member 13, and can improve airtightness.

  The seal member 13 is made of a synthetic rubber such as NBR (acrylonitrile-butadiene rubber), and has a pair of side lips 13a and 13b extending obliquely outward in the radial direction, and radially inward of the side lips 13a and 13b. A grease lip 13c extending obliquely in the direction. The sealing member 13 is fixed by going around from the outer surface of the end of the fitting portion 12a of the core metal 12 to the inner edge of the inner diameter portion 12b. 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 is formed into a substantially L-shaped cross section by pressing from a steel plate having rust prevention ability such as a ferritic stainless steel plate (JIS standard SUS430 series, etc.) or a rust-proof cold rolled steel plate. A cylindrical portion 11a that is press-fitted into the outer diameter surface 3c of the inner ring 3 and a standing plate portion 11b that extends radially outward from the cylindrical portion 11a are provided. The magnetic encoder 14 is integrally joined by vulcanization bonding or the like from the side surface on the inner side of the standing plate portion 11b to the outer end portion. The magnetic encoder 14 is a rotary encoder for detecting the rotational speed of a wheel by mixing magnetic powder such as ferrite in an elastomer such as rubber and magnetizing magnetic poles N and S alternately on the side surface in the circumferential direction.

  In the present embodiment, the side lips 13a and 13b of the seal member 13 are slidably contacted to the outer side (bearing inward side) side surface of the upright plate portion 11b via a predetermined axial nip, and the grease lip 13c is cylindrical. It is slidably contacted with the outer diameter surface of the part 11a via a predetermined axial shimiro. In addition, the end surface on the inner side (outer bearing side) of the seal plate 10 and the side surface on the inner side of the magnetic encoder 14 joined to the standing plate portion 11b of the slinger 11 are set to be substantially flush with each other. The end surface 2b of the outer member 2 and the large-diameter side end surface (large end surface) 3d of the inner ring 3 are set to be flush with each other. As a result, when the sealing device 7 is mounted and fixed between the outer member 2 and the inner ring 3, it can be handled with a simple press-fitting jig, which can improve assemblability and positioning accuracy. And a desired sealing property can be ensured. Here, the term “substantially flush” means, for example, a design target value that is substantially free of steps, that is, a step caused by a processing error or the like should be allowed.

  Here, the magnetic encoder 14 includes an extending portion 15 that extends from the outer end portion of the standing plate portion 11 b of the slinger 11 to the outer side in the axial direction (bearing inward side). The outer diameter surface 15a of the extending portion 15 is formed as a tapered surface that gradually increases in diameter toward the outer side. On the other hand, the seal member 13 wraps and is fixed from the outer surface of the end portion of the fitting portion 12a of the metal core 12 to the inner edge of the inner diameter portion 12b, and the opening 16 joined to the inner diameter of the fitting portion 12a of the metal core 12; The base 17 is joined to the inner diameter part 12b of the cored bar 12. The outer diameter surface 15a of the extending portion 15 of the magnetic encoder 14 is opposed to the opening 16 of the seal member 13 through a slight radial clearance to form a radial labyrinth Lr. The end surface 15b faces the base portion 17 of the seal member 13 through a slight axial clearance, and an axial labyrinth La is configured.

  The inner diameter surface 16a of the opening 16 of the seal member 13 is formed as a tapered surface with an inclination angle of 30 ° or less that gradually decreases in diameter toward the outer side, and the radial labyrinth Lr is configured in a spire shape. That is, in the clearance between the outer diameter surfaces 15a of the extending portions 15 of the opposing magnetic encoder 14, the labyrinth clearance S1 on the inlet side is set to be larger than the labyrinth clearance S2 on the inner side. As a result, an L-shaped labyrinth composed of the radial labyrinth Lr and the axial labyrinth La can be formed simply by extending the magnetic encoder 14 instead of the separate member 15 from the extension portion 15. Even if muddy water or the like enters the sealing device, a pressure difference due to rotation occurs between the inlet side S1 and the inner side S2 of the radial labyrinth clearance, and this pressure difference causes the muddy water to flow. It is possible to provide a sealing device 7 that can be easily generated and discharged and maintain high sealing performance.

  Here, the inlet side S1 of the radial labyrinth clearance is set to 1 to 3 mm (diameter), and the internal clearance S2 is set to 0.5 to 1 mm (diameter). If the clearance S1 on the inlet side exceeds 3 mm, foreign matter such as muddy water can easily enter from the outside. If the clearance S2 on the inner side is less than 0.5, the manufacturing dimensions of the seal member 13 and the magnetic encoder 14 may vary. It is not preferable because both may interfere with each other due to roundness or the like.

  Here, the inner diameter surface 16a of the opening portion 16 of the seal member 13 and the outer diameter surface 15a of the extension portion 15 of the magnetic encoder 14 that are opposed to each other in the radial direction are formed in a tapered surface. It is only necessary that the labyrinth clearance S1 on the inlet side is larger than the labyrinth clearance S2 on the inner side, and the inner diameter surface 16a of the opening 16 of the seal member 13 and the outer diameter surface of the extension portion 15 of the magnetic encoder 14 are used. It is sufficient that at least one of 15a is formed on a tapered surface.

  In addition, here, the plurality of seal lips of the seal member 13 are exemplified by a pair of side lips 13a and 13b and a grease lip 13c. However, the present invention is not limited thereto, and may be a plurality of seal lips. For example, although not shown, it may be composed of a single side lip, dust lip and grease lip.

  In FIG. 3, the modification of the sealing device 7 mentioned above is shown. The sealing device 18 is basically the same as the magnetic encoder 14 described above, except that the same parts, the same parts, or parts or parts having the same function are denoted by the same reference numerals and duplicated. Description is omitted.

  The sealing device 18 is constituted by a pack seal composed of an annular seal plate 10 and a slinger 11 which are arranged to face each other and have a substantially L-shaped cross section. The magnetic encoder 19 is integrally joined by vulcanization bonding or the like from the side surface on the inner side of the standing plate portion 11b of the slinger 11 to the outer end portion, and has an extending portion 20 extending to the outer side in the axial direction.

  Here, the outer diameter surface 15a of the extending portion 20 of the magnetic encoder 19 is formed as a tapered surface with an inclination angle of 30 ° or less that gradually increases in diameter toward the outer side, and the inner diameter surface 20a also faces the outer side. It is formed on a tapered surface that gradually increases in diameter. The outer diameter surface 15a of the extending portion 20 of the magnetic encoder 19 is opposed to the opening portion 16 of the seal member 13 through a slight radial clearance to form a radial labyrinth Lr. The end surface 15b faces the base portion 17 of the seal member 13 through a slight axial clearance, and an axial labyrinth La is configured.

  Thereby, even if muddy water or the like enters the sealing device, the muddy water adhering to or staying in the extending portion 20 of the magnetic encoder 19 flows along the inner diameter surface 20a with the rotation, and the labyrinth Combined with the effect of the pressure difference between the inlet side S1 and the inner side S2 of the clearance, a flow is generated in the muddy water, which is more easily discharged.

  FIG. 4 shows a modification of the sealing device 18 described above. The sealing device 21 basically has the same configuration as that of the slinger 11 described above, but other parts and parts having the same functions or parts having the same functions are denoted by the same reference numerals and duplicated description. Omitted.

  The sealing device 21 is composed of a pack seal including an annular seal plate 10 that is disposed opposite to each other and has a substantially L-shaped cross section, and a slinger 22 that has a substantially U-shaped cross section. Yes. The slinger 22 is formed by press working from a steel plate having rust prevention ability such as a ferritic stainless steel plate or a rust-proof cold-rolled steel plate, and is cylindrically inserted into an outer diameter surface of an inner ring (not shown); A standing plate portion 11b extending radially outward from the cylindrical portion 11a and a cylindrical bent portion 22a extending from the standing plate portion 11b to the outer side (bearing inward side) are provided. Then, the magnetic encoder 23 is integrally joined by vulcanization bonding or the like from the side surface on the inner side of the standing plate portion 11b to the outer surface of the bent portion 22a, and has an extending portion 24 extending to the outer side in the axial direction. Yes.

  Here, the bent portion 22a of the slinger 22 is formed in a tapered surface that gradually increases in diameter toward the outer side, and the outside of the extended portion 24 of the magnetic encoder 23 joined to the outer surface of the bent portion 22a. The diameter surface 24a is also formed as a tapered surface that gradually increases in diameter toward the outer side. The outer diameter surface 24a of the extending portion 24 of the magnetic encoder 23 is opposed to the opening 16 of the seal member 13 through a slight radial clearance to form a radial labyrinth Lr. The end surface 24b faces the base portion 17 of the seal member 13 via a slight axial clearance, and an axial labyrinth La is configured.

  As a result, even if muddy water or the like enters the sealing device, the muddy water adhering to or staying in the bent portion 22a of the slinger 22 flows along the bent portion 22a with the rotation, and the labyrinth. Combined with the effect of the pressure difference between the inlet side S1 and the inner side S2 of the clearance, the muddy water flows easily and is discharged, and the pressure of the muddy water can suppress the deformation of the extension 24, and can be Labyrinth clearance can be maintained.

  FIG. 5 shows a modification of the sealing device 21 described above. The sealing device 25 basically has the same configuration as that of the slinger 22 described above, except that the same parts, the same parts, or parts or parts having the same function are denoted by the same reference numerals and redundantly described. Omitted.

  The sealing device 25 is composed of a pack seal including an annular seal plate 10 that is disposed opposite to each other and has a substantially L-shaped cross section, and a slinger 26 that has a substantially U-shaped cross section. Yes. The slinger 26 is formed by pressing from a steel plate having rust prevention ability such as a ferritic stainless steel plate or a rust-proof cold rolled steel plate, and a cylindrical portion 11a that is press-fitted into an outer diameter surface of an inner ring (not shown); A standing plate portion 11b extending radially outward from the cylindrical portion 11a and a cylindrical bent portion 26a extending from the standing plate portion 11b to the outer side (bearing inward side) are provided, and a distal end portion of the bent portion 26a The step portion 26b is integrally formed. The magnetic encoder 27 is integrally joined by vulcanization bonding or the like from the side surface on the inner side of the upright plate portion 11b to the step portion 26b of the bent portion 26a, and has an extending portion 28 extending outward in the axial direction. ing.

  Here, the bent portion 26a and the stepped portion 26b of the slinger 26 are formed on a tapered surface that gradually increases in diameter toward the outer side, and an extended portion of the magnetic encoder 27 joined to the outer surface of the bent portion 26a. The outer diameter surface 28a of 28 is also formed in the taper surface which expands gradually toward an outer side. The outer diameter surface 28a and the stepped portion 26b of the extending portion 28 of the magnetic encoder 27 are opposed to the opening 16 of the seal member 13 through a slight radial clearance, and a radial labyrinth Lr is formed. The end face 26c of the portion 26b faces the base portion 17 of the seal member 13 via a slight axial clearance, and an axial labyrinth La is configured.

  Thereby, even if muddy water or the like enters the sealing device, the muddy water adhering to or staying at the bent portion 26a and the stepped portion 26b of the slinger 26 is rotated along with the bent portion 26a and the stepped portion. 26b, coupled with the effect of the pressure difference between the inlet side S1 and the inner side S2 of the labyrinth clearance, the muddy water flows easily and is discharged easily. The deformation of the extending portion 28 can be suppressed by the pressure, and a desired labyrinth clearance can be maintained.

  FIG. 6 is a longitudinal sectional view showing a second embodiment of the wheel bearing device provided with the sealing device according to the present invention, and FIG. 7 is a longitudinal sectional view showing one sealing device of FIG. The wheel bearing device is basically the same as the above-described wheel bearing 1 (FIG. 1) except that the structure of the bearing portion is different, and is the same for other parts and parts having the same or similar functions. A duplicate description is omitted with reference numerals.

  The wheel bearing device shown in FIG. 6 is referred to as the third generation on the drive wheel side, and is a double row rolling element that is accommodated so as to roll freely between the inner member 29 and the outer portion 30, and both members 29 and 30. 4 and 4. The inner member 29 includes a hub ring 31 and an inner ring 3 that is press-fitted and fixed to the hub ring 31.

  The hub wheel 31 integrally has a wheel mounting flange 32 for attaching a wheel (not shown) to an end portion on the outer side, and a hub bolt for fixing the wheel at a circumferentially equidistant position of the wheel mounting flange 32. 32a is planted. Further, one (outer side) inner rolling surface 31a and a cylindrical small diameter step portion 31b extending in the axial direction from the inner rolling surface 31a are formed on the outer periphery of the hub wheel 31, and torque transmission is performed on the inner periphery. Serrations (or splines) 31c are formed. The inner ring 3 is formed with the other (inner side) inner raceway surface 3a on the outer periphery, and is press-fitted and fixed to the small-diameter step portion 31b of the hub ring 31 through a predetermined shimiro.

  The hub wheel 31 is formed of medium-high carbon steel containing carbon of 0.40 to 0.80% by weight, such as S53C, and is attached to a wheel that serves as a seal land portion of a seal 33 to be described later, including an inner rolling surface 31a on the outer side. The surface hardness is set to a range of 58 to 64 HRC by induction hardening from the base portion 32b on the inner side of the flange 32 to the small diameter step portion 31b. As a result, not only the wear resistance of the base portion 32b of the wheel mounting flange 32 is improved, but also sufficient mechanical strength against the rotational bending load applied to the wheel mounting flange 32 is obtained. Strength and durability are improved.

  The outer member 30 integrally has a vehicle body mounting flange 30b to be attached to the vehicle body (not shown) on the outer periphery, and a double row facing the inner rolling surfaces 31a and 3a of the inner member 29 on the inner periphery. The outer rolling surfaces 30a, 30a are integrally formed. The outer member 30 is formed of medium and high carbon steel containing 0.40 to 0.80% by weight of carbon such as S53C, as in the case of the hub wheel 31, and at least the double row outer raceway surfaces 30a and 30a are formed by induction hardening. The surface hardness is set in the range of 58 to 64 HRC. The double-row rolling elements 4, 4 are accommodated between the rolling surfaces 30a, 31a and 30a, 3a, and the double-row rolling elements 4, 4 are held by the cages 5 and 5 so as to roll freely. ing.

  In addition, sealing devices 33 and 34 are attached to the opening portion of the annular space formed between the outer member 30 and the inner member 29, and leakage of lubricating grease sealed inside the bearing, rainwater and Dust and the like are prevented from entering the bearing.

  In addition, although the wheel bearing apparatus comprised by the double row angular contact ball bearing which used the ball for the rolling element 4 was illustrated here, it is not restricted to this, The double row tapered roller bearing which uses the tapered roller for the rolling element 4 It may consist of. In addition, here, a third generation structure in which the inner rolling surface 31a is formed directly on the outer periphery of the hub wheel 31 is illustrated, but although not shown, a pair of inner rings are press-fitted and fixed to the small-diameter step portion of the hub wheel. A second generation structure may be used.

  In the present embodiment, the outer side sealing device 33 is constituted by an integral type sealing device including a core bar 35 and a seal member 36 integrally vulcanized and bonded to the core bar 35. A side lip 36a, a dust lip 36b, and a grease lip 36c are provided which are in sliding contact with the base 32b on the inner side of the wheel mounting flange 32 having a circular section in cross section.

  On the other hand, as shown in an enlarged view in FIG. 7, the inner side sealing device 34 is formed so as to face each other and has an annular seal plate 10 having a substantially L-shaped cross section and a substantially U-shaped cross section. It is comprised by the pack seal | sticker which consists of the slinger 26 made. This sealing device 34 basically differs only in the presence or absence of the magnetic encoder 27 of the sealing device 25 (FIG. 5) described above, and the same reference numerals are assigned to the same parts or parts having the same functions. Therefore, the duplicate description is omitted.

  The slinger 26 is formed into a substantially U-shaped cross section by pressing from a steel plate having rust prevention performance, such as a ferritic stainless steel plate or a cold-rolled steel plate treated with rust, and is press-fitted into the outer diameter surface of an inner ring (not shown). A cylindrical portion 11a, a standing plate portion 11b extending radially outward from the cylindrical portion 11a, and a cylindrical bent portion 26a extending from the standing plate portion 11b to the outer side (bearing inward side). A stepped portion 26b is integrally formed at the tip of the bent portion 26a.

  Here, the bent portion 26a and the stepped portion 26b of the slinger 26 are formed in a tapered surface that gradually increases in diameter toward the outer side, and face the opening 16 of the seal member 13 through a slight radial clearance, The direction labyrinth Lr is configured, and the end surface 26c of the stepped portion 26b is opposed to the base portion 17 of the seal member 13 through a slight axial clearance to configure the axial labyrinth La.

  Thereby, even if muddy water or the like enters the sealing device, the muddy water adhering to or staying at the bent portion 26a and the stepped portion 26b of the slinger 26 is rotated along with the bent portion 26a and the stepped portion. In combination with the effect of the pressure difference between the inlet side S3 of the labyrinth clearance where the step portion 26b does not flow and the inner side S2 of the portion where the step portion 26b exists, the muddy water flows and discharges along the portion 26b. The slinger 26 can be shared in response to changes in specifications due to the presence or absence of the magnetic encoder.

  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 sealing device according to the present invention can be applied to a wheel bearing device having a first to third generation structure.

DESCRIPTION OF SYMBOLS 1 Wheel bearing 2 Outer member 2a Outer rolling surface 2b Outer member end surface 3 Inner ring 3a Inner rolling surface 3b Inner ring small diameter side end surface 3c Inner ring outer diameter surface 3d Inner ring large diameter side end surface 4 Rolling element 5 Holding 6, 33 Outer side sealing device 7, 34 Inner side sealing device 8, 12, 35 Core metal 9, 13, 36 Seal member 10 Seal plate 11, 22, 26 Slinger 11 a Cylindrical portion 11 b Standing plate portion 12 a Fitting Part 12b Inner diameter part 13a, 13b, 36a Side lip 13c, 36c Grease lip 14, 19, 23, 27 Magnetic encoder 15, 20, 24, 28 Extension part 15a, 24a, 28a Extension part outer diameter surface 15b Extension End face 16 of the seal part Opening part 16a of the sealing member Inner diameter face 17 of the opening part Base parts 18, 21, 25 Sealing devices 22a, 26a Bending part 24b End face 26b of the extending part Step part 26c Step part End surface 29 Inner member 31 Hub wheel 31b Small diameter step 32 Wheel mounting flange 32a Hub bolt 32b Base 36b on the inner side of the wheel mounting flange Dustrip 50 Sealing device 51 Slinger 51t Slinger radial extending end 52 Encoder 53 Core 53t End portion 54 of the metal core 54 Seal material 54a Side lip 55 Seal main body 56 First turning portion 57 Second turning portion La Axial labyrinth Lr Radial labyrinth Lp Labyrinth portion 1Lp Axial labyrinth 2Lp Radial labyrinth S1 , S3 Labyrinth clearance on the inlet side S2 Labyrinth clearance on the inner side

Claims (3)

Consists of an annular seal plate and slinger arranged opposite each other,
The seal plate includes a cylindrical fitting portion that is press-fitted into the end portion of the outer member, a core bar that extends radially inward from the end portion of the fitting portion, and the core plate. It has a sealing member joined together by sulfur adhesion,
The slinger includes a cylindrical portion that is press-fitted into the inner member, and a standing plate portion that extends radially outward from the cylindrical portion,
In the sealing device, the seal member includes an opening joined to an inner diameter of the fitting portion of the cored bar, and a side lip formed to be inclined radially outward and slidably contact the standing plate portion of the slinger. ,
It includes an extending portion ing from the bent portion integrally formed to extend from the outer end portion of the upright plate portion of the slinger in bearing inwardly, between the opening of the extending portion and the sealing member An axial labyrinth is formed between the radial labyrinth and the end surface of the extension portion and the seal member, and at least one of the outer diameter surface of the extension portion and the inner diameter surface of the opening portion of the seal member There those該径direction labyrinth is formed into a tapered surface is formed on pyramidal, the gap in the radial direction labyrinth inlet side is set larger than the labyrinth gap inner side, the tip portion of the bent portion A stepped portion is provided, and the outer diameter surface of the stepped portion is formed into a tapered surface that gradually increases in diameter toward the bearing inward side, and wraps around from the side surface of the standing plate portion of the slinger to the stepped portion so that it is magnetic to the elastomer. Around the side where body powder is mixed Sealing apparatus characterized by magnetic encoder is bonded to the magnetic poles N, S are magnetized alternately.   The sealing device according to claim 1, wherein an inner diameter of the extending portion of the slinger is formed on a tapered surface that gradually increases in diameter toward the inner side of the bearing. An outer member in which a double row outer rolling surface is integrally formed on the inner periphery;
A hub wheel integrally having a wheel mounting flange for mounting a wheel at one end thereof and having a small-diameter step portion extending in the axial direction on the outer periphery, and at least one inner ring fitted to the small-diameter step portion of the hub ring An inner member in which a double row inner rolling surface facing the outer rolling surface of the double row is formed on the outer periphery,
A double row rolling element housed movably between the rolling surfaces of the inner member and the outer member;
In a wheel bearing device comprising: a sealing device that seals an opening of an annular space formed between the outer member and the inner member;
3. The wheel bearing device according to claim 1, wherein the sealing device comprises the sealing device according to claim 1 or 2 .

Images