JP6534458B2 - Sealing device and wheel bearing device having the same - Google Patents

Description

  The present invention relates to a sealing device for sealing a bearing space, and more particularly to a sealing device having a sufficient sealing property for a long time even in an environment where a large amount of foreign matter such as rain water and mud water exist, and a wheel bearing device provided with 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 rotatably supports a hub wheel for mounting the wheel via a double-row rolling bearing, and is available for driving wheels and driven wheels. For structural reasons, the inner ring rotation method is generally adopted for drive wheels, and the inner ring rotation and outer ring rotation methods are generally adopted for driven wheels. In addition, the wheel bearing device has a structure called first generation in which a wheel bearing consisting of double-row angular contact ball bearings and the like is fitted between a knuckle constituting a suspension system and a hub wheel. A second generation structure in which a vehicle mounting flange or a wheel mounting flange is directly formed on the outer periphery of a member, or a third generation structure in which one inner raceway is directly formed on the outer periphery of a hub wheel It is roughly divided into the fourth generation structure in which the inner raceway is directly formed on the outer periphery of the outer joint member of the fast joint.

  In such a bearing device for a wheel, since it is in the environment directly exposed to rain water, muddy water, etc. while preventing the leak of the grease enclosed inside the bearing, it is strong so that this rain water, muddy water, etc. A sealing device having a good sealing property is mounted. In recent years, longer life has come to be required in wheel bearing devices of this type used under such severe environments. Among sealing devices, a sealing member provided with a sealing lip is attached to an outer member serving as a stationary member, and the sealing lip is in sliding contact with a slinger attached to an inner member, as a sealing member having a particularly high sealing performance. So-called pack seals are commonly used.

  Conventionally, various proposals have been made with respect to a sealing device for a wheel bearing with improved sealing performance, and a representative example of such a sealing device is shown in FIG. The sealing device 50 is composed of a pack seal consisting of an annular seal plate 51 and a slinger 52. The seal plate 51 is composed of a cored bar 54 mounted on the outer member 53 and a seal member 55 integrally joined to the cored bar 54 by vulcanization bonding. The metal core 54 is formed into a substantially L-shaped cross section by press working from a steel plate, and has a cylindrical fitting portion 54a press-fit onto the inner periphery of the end portion of the outer member 53, and radially inward from the fitting portion 54a. And an inwardly extending portion 54b. The seal member 55 is made of a synthetic rubber such as nitrile rubber, and extends outward in the radial direction, and includes a side lip 55a, a grease lip 55b and an intermediate lip 55c formed in a bifurcated shape, and an outer side than the side lip 55a. It has an auxiliary lip 55d projecting radially and curving and extending radially outward.

  On the other hand, the slinger 52 has a cylindrical fitting portion 52a press-fitted to the outer diameter of the inner ring 56, a standing plate portion 52b extending radially outward from the fitting portion 52a, and an inner bearing from the standing plate portion 52b. It has a cylindrical portion 52c axially extending toward the side, and is formed in a substantially U-shaped cross section. Then, the side lip 55a of the seal member 55 is in sliding contact with the upright plate portion 52b, the grease lip 55b and the intermediate lip 55c are in sliding contact with the fitting portion 52a, and the auxiliary lip 55d is the inner side surface of the cylindrical portion 52c. It is in sliding contact with By this auxiliary lip 55d, it is possible to apply an appropriate tension force. The cylindrical portion 52c of the slinger 52 is opposed to the seal plate 51 with a slight radial clearance, whereby a labyrinth seal 57 is formed.

  With this configuration, the labyrinth seal 57 is formed between the cylindrical portion 52c of the slinger 52 and the seal plate 51, and the labyrinth length L does not stop at the thickness of the slinger 52, and the area is wide by the length of the cylindrical portion 52c. Therefore, the effective labyrinth seal 57 can be configured, and it is possible to suppress the entry of muddy water or the like into the inside of the seal. Further, even if muddy water or the like passes through the labyrinth seal 57 and enters the inside of the seal, it is blocked by the auxiliary lip 55d, and the space S where the muddy water or the like accumulates can be minimized as much as possible in comparison with the conventional sealing device. Therefore, it is possible to prevent the side lip 55a from being abraded by foreign substances such as mud and sand contained in muddy water, etc., and to improve sealing performance and durability of the sealing device 50 for a long period of time. The wheel bearing apparatus can be provided (see, for example, Patent Document 1).

JP, 2009-197884, A

  However, in such a conventional sealing device 50, since the auxiliary lip 55d which is in sliding contact with the inner surface of the cylindrical portion 52c of the slinger 52 is curved, it is not only difficult to form by vulcanization but also the auxiliary lip 55d may get caught during assembly. As a result, the assemblability of the sealing device 50 may be concerned, and the rotation with the cylindrical portion 52c of the slinger 52 may vary, and the rotational torque may increase due to the increase of the pressure. Furthermore, since the muddy water which has entered from the outside tends to be accumulated in the curved portion of the auxiliary lip 55d and the accumulated muddy water is difficult to be discharged, there is a possibility that the lip wear is promoted and the sealing performance is lowered.

  The present invention has been made in view of such circumstances, and by making the auxiliary lip into an inclined straight shape without making manufacturing difficult, the muddy water stays even when muddy water enters from the outside. It is conceived to have a structure that eliminates space and is easy to discharge, and it is an object of the present invention to provide a sealing device with improved mud resistance and improved sealing performance, and a wheel bearing device equipped with the same.

In order to achieve the above object, the invention according to claim 1 of the present invention is constituted by an annular seal plate and a slinger disposed opposite to each other, and the seal plate is an end portion of an outer member which becomes a stationary side member. And a cored bar comprising a cylindrical fitting portion to be press-fit into the core and an inner diameter portion extending radially inward from an end of the fitting portion, and the cored bar integrally joined by vulcanization adhesion, A cylindrical member in which the slinger is pressed into the inward member serving as the rotation side member, and a stand extending radially outward from the cylindrical portion. The seal member includes a plate portion, and the seal member is formed to be inclined radially outward, and a side lip slidably contacting the standing plate portion of the slinger, and to be inclined radially inward to the inner diameter side of the side lip A seal formed on and slidingly contacting the cylindrical portion of the slinger A sealing apparatus provided with-up, the sealing member further includes an auxiliary lip extending obliquely radially outward on the outer diameter side of the side lip, the slinger, the bearing from the outer edge of the standing portion The apparatus further comprises an annular collar extending inward , and the collar is opposed to the seal plate via a radial gap to form a labyrinth seal, and the auxiliary lip extends toward the collar. cage, that the tip portion of the auxiliary lip faces the inner surface in the radial direction of the flange portion, is opposed through the inner surface and the radial clearance of the flange portion, a labyrinth seal is formed.

Thus, a cylindrical fitting portion which is constituted by an annular seal plate and a slinger disposed opposite to each other and in which the seal plate is press-fit to the end portion of the outer member serving as the fixed side member, and the fitting portion A core metal comprising an inner diameter portion extending radially inward from an end of the core, and a seal member integrally joined to the core metal by vulcanization adhesion and wrapped around so as to cover the tip end of the fitting portion The slinger includes a cylindrical portion pressed into the inward member serving as the rotation side member, and an upright plate portion extending radially outward from the cylindrical portion, and the seal member is inclined radially outward A sealing device comprising: a side lip formed slidably in contact with an upright plate portion of the slinger, and a seal lip formed inclining radially inward on the inner diameter side of the side lip slidably in contact with the cylindrical portion of the slinger The member is on the outer diameter side of the side lip Further comprising an auxiliary lip extending inclined outwardly, slinger further comprises a flange portion of the annular extending from the outer edge of the standing portion to the bearing inner side, the flange portion via the seal plate and the radial clearance Facing each other, a labyrinth seal is formed, the auxiliary lip extends toward the buttocks, and the tip of the auxiliary lip is radially opposed to the radially inward surface of the buttocks to form the inner diameter surface of the buttocks. Because the labyrinth seal is formed facing the radial clearance, the labyrinth length between the buttocks of the slinger and the seal plate does not stop at the thickness of the slinger and is wider by the length of the buttocks. It is formed over an annular region, and can exert a strong labyrinth effect, and can prevent lip curling during assembly while reducing rotational torque without making manufacturing of the seal member difficult. Can, be external The muddy water or the like from entering into the bearing effectively prevented, it is possible to provide a sealing device with improved sealing performance by increasing the muddy water resistance. In addition, even if muddy water infiltrates from the outside through the labyrinth seal, further labyrinth seal can suppress the infiltration into the inside and wear of the side lip can be prevented, and even if muddy water infiltrates the inside, Since the auxiliary lip is formed in a straight shape with a radial lip and an inner side inclined toward the tip end, the space where the muddy water stays is eliminated and the muddy water is easily discharged to the outside by the centrifugal force. It is possible to secure the initial sealing performance for a long time.

Preferably, as in the invention according to claim 2, the tip end portion of the auxiliary lip is provided on the bearing outer side than the end face of the collar portion and on the outer diameter side than the tip end of the side lip. If so, the sealing performance of the labyrinth seal 17 can be improved.

In the invention according to claim 3 of the present invention, the outer member in which the outer rolling surface of the double row is integrally formed on the inner periphery, and the wheel mounting flange for mounting the wheel at 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, the outer raceway surface of the double row on the outer periphery An inner member formed with opposed double rows of inner rolling surfaces, a double row of rolling elements rollably accommodated between rolling surfaces of the inner member and the outer member, and And a sealing device for sealing the opening of the annular space formed between the outer member and the inner member, wherein the sealing device is the seal according to claim 1 or 2. It consists of a device.

Thus, in the wheel bearing device provided with the sealing device for sealing the opening of the annular space formed between the outer member and the inner member, the sealing device is the device according to claim 1 or 2 . Since it is comprised by the sealing apparatus, the bearing apparatus for wheels which raised the mud-water resistance of the sealing apparatus, and aimed at the sealing improvement in a muddy water environment can be provided.

The sealing device according to the present invention is composed of an annular seal plate and a slinger disposed opposite to each other, and the seal plate is a cylindrical fitting portion press-fitted to the end of the outer member serving as the fixed side member A cored bar comprising an inner diameter portion extending radially inward from an end of the fitting portion, and integrally bonded to the cored bar by vulcanization adhesion, and wrapping around so as to cover the tip end portion of the fitting portion The sealing member includes a joined sealing member, and the slinger includes a cylindrical portion pressed into the inward member serving as the rotation side member, and a rising plate portion extending radially outward from the cylindrical portion. A side lip which is formed to be inclined radially outward, and which is formed to be inclined radially inward on the inner diameter side of the side lip slidingly contacting the standing plate portion of the slinger, and which is in sliding contact to the cylindrical portion of the slinger In a sealing device provided with a sealing lip, Serial seal member, the radially outer side of the side lip inclined radially outwardly further includes an auxiliary lip extending said slinger, the flange portion of the annular extending from an outer edge of the standing portion on the bearing inner side further comprising a the flange portion is opposed through the seal plate and the radial clearance, the labyrinth seal is formed, the auxiliary lip extends toward the flange portion, the tip portion of the auxiliary lip by facing the inner surface and a radial direction of the flange portion, is opposed through the inner surface and the radial clearance of the flange portion, since the labyrinth seal is formed, the flange portion of the slinger and the seal plate The labyrinth length between them is not limited to the thickness of the slinger and is formed over a wide annular area by the length of the buttocks, and a strong labyrinth effect can be exhibited, and it is difficult to manufacture the seal member To be Can reduce lip torque during assembly while reducing rotational torque, effectively prevent muddy water etc. from entering the inside of the bearing from the outside, and improve the sealing performance by enhancing the mud resistance. Can provide a sealed device. In addition, even if muddy water infiltrates from the outside through the labyrinth seal, further labyrinth seal can suppress the infiltration into the inside and wear of the side lip can be prevented, and even if muddy water infiltrates the inside, Since the auxiliary lip is formed in a straight shape with a radial lip and an inner side inclined toward the tip end, the space where the muddy water stays is eliminated and the muddy water is easily discharged to the outside by the centrifugal force. It is possible to secure the initial sealing performance for a long time.

Further, the wheel bearing device according to the present invention integrally has an outer member in which a plurality of rows of outer race surfaces are integrally formed on the inner periphery, and a wheel mounting flange for attaching a wheel to one end portion. A hub ring formed with 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, and a compound facing the outer rolling surface of the double row on the outer periphery An inward member in which an inner raceway surface of a row is formed, a double row of rolling elements rollably accommodated between the respective raceway surfaces of the inward member and the outer member, and the outward member And a sealing device for sealing the opening of the annular space formed between the housing and the inner member, wherein the sealing device comprises the sealing device according to claim 1 or 2 Car, which has improved the sealing performance of the sealing device by enhancing the mud resistance of the sealing device. It is possible to provide the use bearing device.

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. It is a longitudinal cross-sectional view which shows one sealing apparatus of FIG. (A) is a longitudinal cross-sectional view which shows the modification of the sealing apparatus of FIG. 2, (b) is a principal part enlarged view of (a). 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 other modification of the sealing device of FIG. It is a longitudinal cross-sectional view which shows the other modification of the sealing device of FIG. It is a longitudinal cross-sectional view which shows the other modification of the sealing device of FIG. It is a longitudinal cross-sectional view which shows 2nd Embodiment of the bearing for wheels provided with the sealing device which concerns on this invention. It is a longitudinal cross-sectional view which shows one sealing apparatus of FIG. It is a longitudinal cross-sectional view which shows the modification of the sealing device of FIG. It is principal part sectional drawing which shows the conventional sealing device.

  A pack seal comprising an annular seal plate disposed opposite to each other and having an L-shaped cross section and a slinger having a U-shaped cross section, the seal plate serving as a stationary member A cylindrical fitting portion press-fit into the inner periphery of the end portion of the outer member, and a cored bar comprising an inner diameter portion extending radially inward from the end portion of the fitting portion And a cylindrical portion in which the slinger is press-fitted to the outer diameter of the inner ring to be the rotation side member, and the cylindrical portion. And a side lip which is formed to be inclined radially outward and which is in sliding contact with the standing plate portion of the slinger, and an inner side of the side lip The slinger is formed to be inclined radially inward. In a sealing device provided with a grease lip in sliding contact with a cylindrical portion, an annular flange portion extending inward from the outer edge portion of the upright plate portion of the slinger is formed, and from the side surface of the upright plate portion on the bearing outer side A magnetic encoder is integrally joined along the outer peripheral surface of the collar portion, and the outer diameter surface of the magnetic encoder and the cylindrical portion of the seal plate are opposed to each other via a radial gap to form a labyrinth seal and The side lip is formed in a straight shape that inclines toward the tip toward the tip on the outer diameter side of the side lip, and the tip portion is opposed to the inner diameter surface of the flange portion of the slinger via a radial clearance to form a labyrinth seal It is done.

Hereinafter, embodiments of the present invention will be described in detail based on the drawings.
FIG. 1 is a longitudinal sectional view showing a first embodiment of a bearing for a wheel provided with a sealing device according to the present invention, FIG. 2 is a sectional view showing one sealing device of FIG. 1, FIG. 2 is a longitudinal sectional view showing a modification of the sealing device of FIG. 2, (b) is an enlarged view of a main part of (a), FIG. 4 is a longitudinal sectional view showing a modification of the sealing device of FIG. 2 is a longitudinal sectional view showing another modification of the sealing device of FIG. 2, FIG. 6 is a longitudinal sectional view showing another modification of the sealing device of FIG. 2, and FIG. 7 is another modification of the sealing device of FIG. It is a longitudinal section showing an example. In the following description, the side closer to the outer side of the vehicle in a state of being assembled to the vehicle is referred to as the outer side (left side in FIG. 1) and the side closer to the center as the inner side (right side in FIG. 1).

  The wheel bearing 1 is referred to as a first generation used in a wheel bearing device, and includes an outer member (outer ring) 2 and a double row outer raceway surface 2a formed integrally with an inner periphery thereof. A pair of inner rings (inward members) 3 and 3 integrally formed with the outer raceway surfaces 2a on the outer periphery and the inner raceway surfaces 3a opposed to the double row outer raceway surfaces 2a, 2a and 2 are accommodated between the two raceway surfaces. Double rows of rolling elements (balls) 4, 4; cages 5, 5 for rollingly holding these rolling elements 4, 4; and formed between the outer member 2 and the pair of inner rings 3, 3 And sealing devices 6, 7 mounted at the opening of the annular space.

  The outer member 2 is made of high carbon chromium bearing steel such as SUJ 2 (JIS G 4805) or carburized steel. In the case of high carbon chromium bearing steel, after being quenching quenched at 820 to 860 ° C., it is tempered at 160 to 200 ° C. and hardened to the core portion in the range of 58 to 64 HRC. In the case of carburized steel, the surface is hardened to a range of 58 to 64 HRC. On the other hand, the inner ring 3 is also made of high carbon chromium bearing steel such as SUJ 2 or carburized steel like the outer member 2, and in the case of high carbon chromium bearing steel, the core is hardened in the range of 58 to 64 HRC and carburized steel In the case of, the surface is hardened in the range of 58 to 64 HRC. Further, the rolling element 4 is made of high carbon chromium bearing steel such as SUJ 2 and is hardened in the range of 62 to 67 HRC up to the core portion by squib hardening.

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

  In addition, although the thing comprised with the double row angular contact ball bearing which used the ball | bowl for the rolling element 4 as the bearing 1 for wheels was illustrated here, the double row conical roller using a tapered roller not only this but the rolling element 4 It may be configured by a bearing.

  Of the sealing devices 6 and 7, the sealing device 6 on the outer side has a cored bar 8 press-fitted to the inner periphery of the outer side end of the outer side member 2 serving as the fixed side via a predetermined mesh. A seal 8 is integrally formed of a sealing member 9 integrally joined by vulcanization bonding and formed of synthetic rubber or the like.

  Further, as shown on an enlarged scale in FIG. 2, the inner side sealing devices 7 are arranged opposite to each other, and have an annular seal plate 10 having a substantially L-shaped cross section, and a substantially U-shaped cross section. It is comprised by the composite type | mold seal | sticker which consists of the formed slinger 11, and what is called a pack seal. The seal plate 10 comprises a core 12 mounted on the outer member 2 and a seal 13 integrally joined to the core 12 by vulcanization bonding.

  The cored bar 12 is pressed from a steel plate having antirust ability such as an austenitic stainless steel plate (SUS304 series of JIS standard) or a cold-rolled steel plate subjected to antirust treatment (SPCC series of JIS standard) or the like. It is formed in an L shape. The metal core 12 is press-fit into the outer member 2 and has a cylindrical fitting portion 12a whose end is slightly reduced in diameter and formed thin, and an inner diameter extending radially inward from the fitting portion 12a. And a unit 12b. Then, the seal member 13 wraps around and is joined so as to cover the front end portion of the fitting portion 12a, and forms a half metal structure. As a result, an appropriate fitting force can be secured, and entry of mud water or the like from the fitting surface due to the pressure bonding of the sealing member 13 can be prevented to improve the airtightness.

  The sealing member 13 is made of a synthetic rubber such as NBR (acrylonitrile-butadiene rubber), and is provided radially inward in the radial direction toward the radially inner side of the pair of side lips 13a and 13b extending obliquely outward in the radial direction. It has a grease lip 13c formed inclined in one direction, and an auxiliary lip 13d extending in a radially outward direction on the outer diameter side of the side lip 13a. The seal member 13 is fixed by going around from the outer surface of the end portion of the fitting portion 12 a of the core 12 to the inner edge of the inner diameter portion 12 b. The material of the sealing member 13 is, besides NBR, for example, HNBR (hydrogenated acrylonitrile-butadiene rubber), EPM, EPDM (ethylene-propylene rubber), etc. excellent in heat resistance, etc., heat resistance, chemical resistance Examples include ACM (polyacrylic rubber), FKM (fluorinated rubber), silicone rubber and the like, which have excellent properties.

  On the other hand, the slinger 11 is formed from a steel plate having an antirust ability such as an austenitic stainless steel plate or a cold-rolled steel plate subjected to antirust treatment by press working into a U-shape in cross section. A cylindrical portion 11a to be press-fitted, a standing plate portion 11b extending radially outward from the cylindrical portion 11a, and a cylindrical collar portion 11c extending to the outer side (inward bearing side) from the outer edge portion of the standing plate portion 11b. And have. The magnetic encoder 14 is integrally joined by vulcanization adhesion or the like from the side surface on the inner side of the standing plate portion 11b to the outer peripheral surface of the collar portion 11c. In the magnetic encoder 14, magnetic powder such as ferrite is mixed in an elastomer such as rubber, and the magnetic poles N and S are alternately magnetized in the circumferential direction to constitute a rotary encoder for detecting the rotational speed of the wheel. The outer diameter surface of the magnetic encoder 14 is opposed to the cylindrical portion of the seal plate 10 with a slight radial clearance, whereby a labyrinth seal 15 is formed.

  The side lips 13a and 13b of the seal member 13 are in sliding contact with the side surface on the outer side (inward bearing side) of the upstanding plate portion 11b via a predetermined axial direction, and the grease lip 13c is fixed to the cylindrical portion 11a. It is in sliding contact via the radial direction mesh.

  In the present embodiment, the end face on the inner side (bearing outer side) of the seal plate 10 and the side face on the inner side of the upright plate portion 11b of the slinger 11 are set substantially flush with each other. And the large diameter end face (large end face) 3d of the inner ring 3 are flush with each other. As a result, when the sealing device 7 is mounted between the outer member 2 and the inner ring 3 and positioned and fixed, it can be handled with a simple press-in jig, and assemblability can be improved, and the positioning accuracy can be improved. And the desired sealing performance can be ensured. The term "substantially flush" as used herein means, for example, a target value of design and a state without substantially any level difference, that is, a level difference caused by a processing error or the like should naturally be tolerated.

  Here, the auxiliary lip 13d of the seal member 13 is formed in a straight shape that inclines toward the tip toward the inner side (bearing outer side), and the tip portion is slightly smaller than the inner diameter surface 16 of the flange portion 11c of the slinger 11. The labyrinth seal 17 is formed facing the radial clearance. The radial clearance δ is set in the range of 0.1 to 1.0 mm (diameter), preferably 0.3 to 0.8 mm. If the radial clearance δ is less than 0.1 mm, there is a possibility that the auxiliary lip 13d may be worn due to the contact between the parts due to the dimensional variation of each part, an assembly error, etc. . If it exceeds 1.0 mm, the effect as a labyrinth seal is halved, which is not preferable.

  Further, the tip of the auxiliary lip 13d is disposed on the inner side (a> 0) than the end face of the flange 11c of the slinger 11 and on the outer diameter side (b> 0) than the tip of the side lip 13a on the outer diameter side. It is done. Thereby, the sealing performance of the labyrinth seal 17 can be improved.

  Thus, the labyrinth seal 15 is formed between the outer diameter surface of the magnetic encoder 14 joined to the slinger 11 and the cylindrical portion of the seal plate 10, and the labyrinth length does not stop within the thickness of the slinger 11. Since it is formed over a wide annular region by the length of the collar portion 11c (here, the outer diameter surface of the magnetic encoder 14), a strong labyrinth effect can be exhibited, and the tip of the auxiliary lip 13d Since the labyrinth seal 17 is formed between the portion and the inner diameter surface 16 of the flange portion 11c of the slinger 11, the lip torque during assembly can be reduced while reducing the rotational torque without making the manufacturing of the seal member 13 difficult. It is possible to prevent intrusion and to effectively prevent muddy water and the like from invading the inside of the bearing from the outside, and to provide a sealing device 7 having enhanced mud water resistance and improved sealing performance. Rukoto can.

  In addition, even if muddy water infiltrates through the labyrinth seal 15 from the outside, it can suppress the intrusion to the inside by the further labyrinth seal 17 and can prevent the abrasion of the side lip 13a, and the muddy water infiltrates the inside, for example. Also, since the auxiliary lip 13d is formed in a straight shape, with the auxiliary lip 13d inclined radially outward and toward the tip to the inner side, the space for muddy water is eliminated and the muddy water is easily made by centrifugal force. It can be discharged to the outside, and the initial sealing performance can be ensured over a long period of time.

  In addition, although the some seal lip of the seal member 13 illustrated what was comprised by a pair of side lip 13a, 13b and the grease lip 13c here, if it comprised by not only this but several seal lip For example, although not shown, it may be composed of a single side lip and a dust lip and a grease lip.

  The sealing device 18 shown in FIG. 3A is a modification of the above-described sealing device 7 (FIG. 2). Basically, the sealing device 18 is basically the same as the sealing device 7 and the slinger 11 except that the shapes of the sealing device 7 and the slinger 11 are different. The explanation is omitted.

  The sealing device 18 is a pack seal comprising an annular seal plate 10 disposed opposite to each other and having a substantially L-shaped cross section and a slinger 19 having a substantially U-shaped cross section. The slinger 19 is formed from a steel plate having an antirust ability such as an austenitic stainless steel plate or a cold-rolled steel plate subjected to antirust treatment by press working into a substantially U-shaped cross section, and a cylindrical portion 11a and the cylindrical portion 11a. It comprises an upright plate portion 11b extending radially outward from the above, and an annular flange portion 19a which is inclined from the outer edge portion of the upright plate portion 11b to the outer side to expand in diameter.

  Further, the magnetic encoder 20 is integrally joined by vulcanization adhesion or the like from the side surface on the inner side of the standing plate portion 11b to the outer peripheral surface of the flange portion 19a. In the magnetic encoder 20, magnetic powder such as ferrite is mixed in an elastomer such as rubber, and the magnetic poles N and S are alternately magnetized in the circumferential direction. The outer diameter surface of the magnetic encoder 20 is opposed to the cylindrical portion of the seal plate 10 with a slight flange-like radial clearance, thereby forming a labyrinth seal 21.

  Here, in the present embodiment, an annular labyrinth seal 21 is formed between the magnetic encoder 20 of the slinger 19 and the seal plate 10 as in the embodiment described above, and the tip of the auxiliary lip 13 d is the slinger 19. A labyrinth seal 23 is formed between the flange portion 19a and the inner diameter surface 22 of the flange portion 19a. As a result, it is possible to prevent entry into the inside by the auxiliary lip 13d and prevent the wear of the side lip 13a while preventing lip curling during assembly, and as shown in FIG. 3 (b), muddy water Even when it enters the inside along a path of b.fwdarw.r.o.-ha, it becomes difficult to stay in this part, and muddy water is easily discharged by a path of d due to the inclined ridge portion 19a.

  The sealing device 24 shown in FIG. 4 is a modification of the above-mentioned sealing device 18 (FIG. 3). Basically, the sealing device 24 is different only in the configuration of the sealing device 18 and the magnetic encoder 20 described above, and the same parts or parts having the same functions or parts having the same functions are denoted by the same reference numerals. I omit explanation.

  The sealing device 24 is a pack seal comprising an annular seal plate 10 disposed opposite to each other and having a substantially L-shaped cross section and a slinger 19 having a substantially U-shaped cross section. The magnetic encoder 25 is integrally joined to the slinger 19 by vulcanization adhesion or the like so that the outer diameter surface 25a is horizontal from the inner side surface of the standing plate portion 11b to the outer peripheral surface of the flange portion 19a. ing. In the magnetic encoder 25, magnetic powder such as ferrite is mixed in an elastomer such as rubber, and the magnetic poles N and S are alternately magnetized in the circumferential direction. The outer diameter surface 25a of the magnetic encoder 25 is opposed to the cylindrical portion of the seal plate 10 with a slight radial clearance, whereby a labyrinth seal 15 is formed.

  As in the present embodiment, the outer diameter surface 25a of the magnetic encoder 25 is formed horizontally even if the ridge portion 19a of the slinger 19 is formed to be inclined so that the muddy water entering the inside can be easily discharged. Since the labyrinth length can be formed over a wide annular area by the length of the outer diameter surface 25a of the magnetic encoder 25 without being limited to the thickness of the slinger 19, a stronger labyrinth effect is exhibited. be able to.

  The sealing device 26 shown in FIG. 5 is another modification of the above-mentioned sealing device 7 (FIG. 2). Basically, the sealing device 26 is basically the same as the sealing device 7 and the slinger 11 except that the shapes of the sealing device 7 and the slinger 11 are different. The explanation is omitted.

  The sealing device 26 is constituted by a pack seal comprising an annular seal plate 10 having a substantially L-shaped cross section and disposed to face each other and a slinger 27. The slinger 27 is formed from a steel plate having an antirust ability such as an austenitic stainless steel plate or a cold-rolled steel plate subjected to antirust treatment by press forming into a U-shape in cross section and a cylindrical portion 11a and the cylindrical portion 11a A standing plate portion 11b extending radially outward and a cylindrical collar portion 27a extending to the outer side from the outer edge portion of the standing plate portion 11b are provided.

  Here, in the present embodiment, the chamfered portion 28 is formed on the inner diameter side of the end portion of the flange portion 27 a of the slinger 27. Then, the tip end portion of the auxiliary lip 13d is opposed to the chamfered portion 28 through a slight radial clearance, and the labyrinth seal 29 is formed. As a result, similar to the above-described embodiment, the auxiliary lip 13d can suppress the entry into the inside and prevent the wear of the side lip 13a while preventing the lip from being caught during assembly, and the mud can enter inside. Even in such a case, muddy water is difficult to stay at this portion, and muddy water is easily discharged by the chamfered portion 28 of the inclined ridge portion 27a.

  The sealing device 30 shown in FIG. 6 is another modification of the sealing device 7 (FIG. 2) described above. This sealing device 30 basically differs only in the shape of the sealing device 7 and the slinger 11 described above, and the same parts or parts having the same function or parts or parts having similar functions are denoted by the same reference numerals, Omit.

  The sealing device 30 is constituted by a pack seal comprising an annular seal plate 10 disposed opposite to each other and having a substantially L-shaped cross section and a slinger 31 having a substantially U-shaped cross section. The slinger 31 is formed from a steel plate having an antirust ability such as an austenitic stainless steel plate or a cold-rolled steel plate subjected to antirust treatment by press forming into a U-shape in cross section and a cylindrical portion 11a and the cylindrical portion 11a A standing plate portion 11b extending radially outward and a cylindrical collar portion 31a extending to the outer side from the outer edge portion of the standing plate portion 11b are provided.

  Here, in the present embodiment, the step portion 32 which is expanded in diameter is formed at the end portion of the flange portion 31 a of the slinger 31. The step portion 32 is formed by pressing and spreading. The distal end portion of the auxiliary lip 13d is opposed to the inner diameter surface 32a of the step portion 32 through a slight L-shaped annular clearance, thereby forming a labyrinth seal 33. As a result, the labyrinth seal 33 constituted by the auxiliary lip 13d can suppress the infiltration into the inside, and the wear of the side lip 13a can be prevented.

  On the other hand, the magnetic encoder 34 is added so that the outer diameter surface thereof is substantially flush with the outer diameter surface 32b of the step portion 32 along the step portion 32 of the flange portion 31a from the inner side surface of the upright plate portion 11b. It is integrally joined by vulcanization adhesion and the like. In the magnetic encoder 34, magnetic powder such as ferrite is mixed in an elastomer such as rubber, and the magnetic poles N and S are alternately magnetized in the circumferential direction. The magnetic encoder 34 and the outer diameter surface 32b of the step portion 32 are opposed to the cylindrical portion of the seal plate 10 with a slight radial clearance, to form a labyrinth seal 15.

  The sealing device 35 shown in FIG. 7 is a modification of the sealing device 30 (FIG. 6) described above. Basically, the sealing device 35 is different only in the presence or absence of the sealing device 30 and the magnetic encoder 34 described above, and the same parts or parts having the same functions or parts or parts having similar functions are denoted by the same reference numerals. I omit explanation.

  The sealing device 35 is a pack seal comprising an annular seal plate 10 disposed opposite to each other and having a substantially L-shaped cross section, and a slinger 31 having a substantially U-shaped cross section. This embodiment has a structure in which the magnetic encoder 34 is not joined to the slinger 31 as in the embodiment described above, but the outer diameter surface 32 b of the step portion 32 of the flange portion 31 a in the slinger 31 is a cylinder of the seal plate 10 A labyrinth seal 15 'is formed to face the portion with a slight radial clearance. As described above, in the present embodiment, the slinger 31 can be shared with the specification in which the magnetic encoder 34 is joined and the specification in which the magnetic encoder 34 is not joined, which can contribute to the standardization of parts and can achieve cost reduction.

  FIG. 8 is a longitudinal sectional view showing a second embodiment of a wheel bearing having a sealing device according to the present invention, and FIG. 9 is a longitudinal sectional view showing one sealing device of FIG. The wheel bearing is basically the same as the wheel bearing 1 (FIG. 1) described above except that the configuration of the bearing portion is different, and other identical parts, parts having the same parts or parts or parts having similar functions have the same reference numerals. To omit duplicate descriptions.

  This wheel bearing is referred to as the third generation on the drive wheel side, and includes inward members 36 and outward members 37, and double rows of rolling elements 4, 4 rollably housed between both members 36, 37 Is equipped. The inward member 36 comprises a hub wheel 38 and an inner ring 3 press-fitted and fixed to the hub wheel 38.

  The hub wheel 38 integrally has a wheel mounting flange 39 for attaching a wheel (not shown) at an end on the outer side, and a hub bolt for fixing the wheel at a circumferential equidistant position of the wheel mounting flange 39 39a is planted. Further, on the outer periphery of the hub wheel 38, one (outer side) inner raceway surface 38a and a cylindrical small diameter step portion 38b axially extending from the inner raceway surface 38a are formed. Or spline) 38c is formed. The inner race 3 has the other (inner side) inner raceway 3a formed on the outer periphery, and is press-fitted and fixed to the small diameter step 38b of the hub wheel 38 via a predetermined mesh.

  The hub wheel 38 is formed of medium-high carbon steel containing 0.40 to 0.80% by weight of carbon such as S53C, etc., and is wheel-mounted to be a seal land portion of the seal 40 described later including the inner side rolling surface 38a on the outer side. The surface hardness is hardened to a range of 58 to 64 HRC by induction hardening from the base portion 39b on the inner side of the flange 39 to the small diameter step portion 38b. As a result, not only the wear resistance of the base 39 b of the wheel mounting flange 39 is improved, but the mechanical strength against rotational bending load applied to the wheel mounting flange 39 is sufficient. Strength and durability improve.

  The outer member 37 integrally has a vehicle body mounting flange 37b on the outer periphery for attachment to a vehicle body (not shown), and a double row facing the inner raceway surfaces 38a and 3a of the inner member 36 on the inner periphery. The outer raceways 37a, 37a are integrally formed. Similar to the hub wheel 38, the outward member 37 is formed of medium-high carbon steel containing 0.40 to 0.80% by weight of carbon such as S53C, and at least the double row of outer raceway surfaces 37a and 37a are induction hardened. The surface hardness is hardened in the range of 58 to 64 HRC. Then, double rows of rolling elements 4, 4 are accommodated between the respective rolling contact surfaces 37a, 38a and 37a, 3a, and these double rows of rolling elements 4, 4 are rotatably held by the cages 5, 5. ing. Sealing devices 40 and 41 are attached to the opening of the annular space formed between the outer member 37 and the inner member 36, and leakage of lubricating grease sealed in the bearing, rain water from the outside, Dust and the like are prevented from entering the inside of the bearing.

  In addition, although the bearing apparatus for wheels comprised with the double row angular contact ball bearing which used the ball | bowl for the rolling element 4 was illustrated here, the double row conical roller bearing which used not only this but the rolling element 4 conical roller It may be composed of Furthermore, although the third generation structure in which the inner raceway surface 38a is directly formed on the outer periphery of the hub wheel 38 is illustrated here, although not shown, a pair of inner rings are press-fitted and fixed to the small diameter step portion of the hub wheel. It may be a second generation structure.

  In the present embodiment, the sealing device 40 on the outer side is constituted by an integral sealing device comprising a core metal 42 and a seal member 43 integrally bonded by vulcanization to the core metal 42, and the seal member 43 is It has a side lip 43a, a dust lip 43b and a grease lip 43c which are in sliding contact with the base portion 39b on the inner side of the wheel mounting flange 39.

  On the other hand, as shown on an enlarged scale in FIG. 9, the inner side sealing devices 41 are disposed opposite to each other, and are formed in a substantially U-shaped cross section with an annular seal plate 10 having a substantially L-shaped cross section. And a pack seal consisting of the slinger 44. Basically, the sealing device 41 is the same as the sealing device 7 (FIG. 2) described above except that the shape of the slinger 11 is different, and the same parts or parts having the same functions are denoted by the same reference numerals. Duplicate descriptions will be omitted.

  The slinger 44 is formed from a steel plate having an antirust ability such as an austenitic stainless steel plate or a cold-rolled steel plate subjected to antirust treatment by press forming into a U-shape in cross section and a cylindrical portion 11a and the cylindrical portion 11a A standing plate portion 11b extending radially outward and a cylindrical collar portion 44a extending to the outer side from the outer edge portion of the standing plate portion 11b are provided.

  Here, in the present embodiment, a bent portion 45 which protrudes outward in the radial direction is formed at the end of the flange portion 44 a of the slinger 44. The bent portion 45 is formed by bending by press processing. The tip end portion of the auxiliary lip 13d is opposed to the inner diameter surface 45a of the bent portion 45 with a slight radial clearance, whereby a labyrinth seal 17 is formed. As a result, the labyrinth seal 17 formed of the auxiliary lip 13d can suppress the entry into the inside and prevent the wear of the side lip 13a.

  On the other hand, the magnetic encoder 46 is such that the outer diameter surface thereof is substantially flush with the outer diameter surface 45 b of the bent portion 45 from the inner side surface of the upright plate portion 11 b along the bent portion 45 of the flange portion 44 a. Are integrally joined to each other by vulcanization bonding or the like. In the magnetic encoder 46, magnetic powder such as ferrite is mixed in an elastomer such as rubber, and the magnetic poles N and S are alternately magnetized in the circumferential direction. The magnetic encoder 46 and the outer diameter surface 45b of the bent portion 45 are opposed to the cylindrical portion of the seal plate 10 with a slight radial clearance, thereby forming a labyrinth seal 15.

  The sealing device 47 shown in FIG. 10 is a modification of the above-mentioned sealing device 41 (FIG. 9). Basically, the sealing device 47 is different only in the presence or absence of the sealing device 41 and the magnetic encoder 46 described above, and the same parts or parts having the same functions or parts or parts having similar functions are denoted by the same reference numerals. I omit explanation.

  The sealing device 47 is a pack seal comprising an annular seal plate 10 disposed opposite to each other and having a substantially L-shaped cross section, and a slinger 44 having a substantially U-shaped cross section. Although this embodiment has a structure in which the magnetic encoder 46 is not joined to the slinger 44 as in the embodiment described above, the outer diameter surface 45 b of the bent portion 45 of the flange portion 44 a in the slinger 44 is the seal plate 10. A labyrinth seal 15 'is formed to face the cylindrical portion with a slight radial clearance. As described above, in the present embodiment, the slinger 44 can be shared with the specification in which the magnetic encoder 46 is joined and the specification in which the magnetic encoder 46 is not joined, which can contribute to the standardization of parts and can achieve cost reduction.

  Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments in any way, and is merely an example, and various modifications can be made without departing from the scope of the present invention. The scope of the present invention is, of course, indicated by the description of the claims, and the meaning of equivalents described in the claims, and all modifications within the scope. Including.

  The sealing device according to the present invention can be applied to the inner ring rotation type first to fourth generation wheel bearings.

1 Wheel bearing 2, 37 Outer member 2a, 37a Outer raceway surface 2b End face of outer member 3 Inner ring 3a, 38a Inner raceway surface 3b Small diameter end face 3c of inner ring Outer diameter surface 3d Inner ring Large diameter side of inner ring End face 4 Rolling element 5 Retainer 6, 40 Outer side sealing device 7, 18, 24, 26, 30, 35, 41, 47 Inner side sealing device 8, 12, 42 Core metal 9, 13, 43 Seal member 10 Seal plate 11, 19, 27, 31, 44 Slinger 11a Cylindrical portion 11b Standing plate portion 11c, 19a, 27a, 31a, 44a Flange portion 12a Fitting portion 12b Inner diameter portion 13a, 13b, 43a Side lip 13c, 43c Grease lip 13d Auxiliary lip 14, 20, 25, 34, 46 Magnetic encoder 15, 15 ', 17, 21, 23, 29, 33 Labyrinth seal 16, 22 Inner diameter surface 25a of ridge portion Magnetic Encoder outer diameter surface 28 chamfered portion 32 step portion 32a inner diameter surface 32b of step portion outer diameter surface 36 step member inward member 37b vehicle mounting flange 38 hub wheel 38b small diameter stepped portion 38c serration 39 vehicle mounting flange 39a hub bolt 39b wheel mounting Flange base 43b Dust strip 45 Bent portion 45a Inner diameter surface 45b of the bent portion Outer diameter surface 50 of the bent portion Sealing device 51 Sealing plate 52 Slinger 52a Fitting portion 52b Standing plate portion 52c Cylindrical portion 53 Outer member 54 Core Gold 54a Fitting portion 54b Inner diameter portion 55 Seal member 55a Side lip 55b Grease lip 55c Intermediate lip 55d Auxiliary lip 56 Inner ring 57 Labyrinth seal a Dimension from the tip of the auxiliary lip to the end face of the collar b b From the tip of the auxiliary lip to the side lip Dimension L up to the tip L labyrinth length S space δ labyrin Gap

Claims (3)

It consists of an annular seal plate and slinger placed opposite each other,
A metal core bar having a cylindrical fitting portion in which the seal plate is press-fitted into the end portion of the outer member to be the stationary side member, and an inner diameter portion extending radially inward from the end portion of the fitting portion; And a seal member integrally joined to the metal core by vulcanization adhesion, and wrapped around and joined so as to cover the tip of the fitting portion,
The slinger includes a cylindrical portion pressed into the inward member serving as the rotation side member, and a rising plate portion extending radially outward from the cylindrical portion.
The sealing member is formed so as to be inclined radially outward, and is formed so as to be inclined radially inward on the inner diameter side of the side lip and in sliding contact with the standing plate portion of the slinger. In a sealing device provided with a seal lip slidingly contacting a cylindrical portion,
The seal member further includes an auxiliary lip that is inclined radially outward on the outer diameter side of the side lip,
The slinger further comprises a flange portion of the annular extending from an outer edge of the standing portion on the bearing inner side,
The flange portion of this is opposed through the seal plate and the radial clearance, the labyrinth seal is formed,
Before SL auxiliary lip extends toward the flange portion, that end portion of the auxiliary lip faces the inner surface in the radial direction of the flange portion, through the inner surface and the radial clearance of the flange portion A sealing device characterized in that a labyrinth seal is formed facing each other. 2. The sealing device according to claim 1, wherein the tip of the auxiliary lip is provided on the bearing outer side than the end face of the flange portion and on the outer diameter side of the tip of the side lip. An outer member in which a plurality of rows of outer race surfaces are integrally formed on the inner periphery,
A hub wheel integrally formed with a wheel mounting flange for mounting a wheel at one end, and having an axially extending small diameter step formed on an outer periphery, and at least one inner ring fitted to the small diameter step of the hub wheel An inner member having a plurality of rows of inner rolling surfaces opposed to the plurality of rows of outer rolling surfaces formed on the outer periphery thereof;
Double rows of rolling elements rollably accommodated between rolling surfaces of the inward member and the outward member;
And a sealing device for sealing the opening of the annular space formed between the outer member and the inner member.
A bearing device for a wheel, wherein the sealing device comprises the sealing device according to claim 1 or 2.

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