JP2018048676A - Wheel bearing device - Google Patents

Abstract

A wheel bearing device capable of improving sealing performance without increasing rotational torque is provided. An outer ring that is an outer member, a hub ring that is an inner member, at least one inner ring that is press-fitted into the hub ring, and rolling of each of the inner member and the outer member. A rolling element accommodated between the surfaces so as to roll freely and a seal plate 7 are fitted to the outer member, and a slinger 8 having a standing plate portion 8b faces the seal plate 7 to the inner member. The seal plate 7 is provided with a seal lip, the slinger 8 is provided with a magnetic encoder 8 c on the standing plate portion 8 b, and the seal lip contacts the slinger 8 so that the space between the outer ring 2 and the inner member is provided. In the wheel bearing device 1 including the sealing member 6 to be sealed, a wall portion 8d that is spaced from the magnetic encoder 8c and extends toward the sealing plate 7 is formed at an end portion of the standing plate portion 8b, and the wall portion 8d The seal plate 7 is coupled with the magnetic encoder 8c. Annular groove 10 is formed radially inward. [Selection] Figure 3

Description

  The present invention relates to a wheel bearing device. Specifically, the present invention relates to a wheel bearing device including a seal member that forms a labyrinth.

  2. Description of the Related Art Conventionally, a wheel bearing device that rotatably supports a wheel in a suspension device such as an automobile is known. In a wheel bearing device, a hub wheel (inner member) connected to a wheel is rotatably supported by an outer member via a rolling element. In the wheel bearing device, the grease inside the outer member is reduced or rainwater or dust gets in, so that the raceway surfaces of the rolling elements and the inner member are damaged and the bearing life is shortened. For this reason, in the wheel bearing device, a seal member is provided between the outer member and the inner member in order to prevent leakage of grease enclosed therein and to prevent rainwater and dust from entering from the outside. Is provided.

  In such a wheel bearing device, in order to obtain a longer bearing life, a seal member is provided with a plurality of seal mechanisms to improve the sealing performance. The labyrinth structure part is comprised by the seal member by the some seal lip. With this configuration, the pack seal can suppress rainwater and dust from entering the tip of the seal lip due to the labyrinth, prevent damage to the tip of the seal lip, and improve the sealing performance. For example, as described in Patent Document 1.

  The wheel bearing device described in Patent Literature 1 includes a cylindrical outer member, an inner ring constituting the inner member, a rolling element that rotatably supports the inner ring, and a seal that seals the opening. . The seal is composed of a pack seal in which a seal plate fitted to the outer member and a slinger fitted to the inner ring are arranged to face each other. The slinger is formed with a cylindrical portion bent in a cylindrical shape in the axial direction from the standing wall portion. The seal has a labyrinth formed by the cylindrical portion of the slinger facing the seal plate via a slight radial gap. The seal is provided with a plurality of seal lips so that muddy water or the like that has passed through the non-contact labyrinth does not enter the inside of the bearing device.

  The seal is provided with an auxiliary lip that is in contact with the cylindrical portion of the slinger, in addition to the axial lip that is in contact with the slinger's vertical plate, the intermediate lip and the radial lip that are in contact with the fitting portion of the slinger. . As described above, the wheel bearing device is configured so that the sealing performance is improved by the plurality of lips so that muddy water or the like that has passed through the labyrinth does not enter the inside of the bearing device. However, since the seal lip comes into contact with the slinger and causes sliding resistance, the rotational torque of the seal increases as the number of lip seals increases. For this reason, the technique described in Patent Document 1 is disadvantageous in that the rotational torque of the seal increases because the auxiliary lip contacts the slinger.

JP 2009-197884 A

  The present invention has been made in view of the above situation, and an object thereof is to provide a wheel bearing device capable of improving the sealing performance without increasing the rotational torque.

  That is, in a wheel bearing device, an outer member in which a double row outer rolling surface is integrally formed on the inner periphery, a hub wheel in which a small-diameter step portion extending in the axial direction is formed on the outer periphery, and the hub wheel An inner member formed of at least one inner ring press-fitted into the small-diameter step portion, and formed with a double-row inner rolling surface facing the double-row outer rolling surface on the outer periphery, the inner member and the inner member A double-row rolling element accommodated between the rolling surfaces of the outer member so as to roll freely, and a seal plate is fitted into the opening of the outer member and has a standing plate portion extending radially outward. A slinger is fitted to the outer peripheral portion of the inner member so as to face the seal plate, and at least one seal lip made of an elastic body is provided on the seal plate, and is formed on the outer surface of the standing plate portion of the slinger. A magnetic encoder is provided, and the seal lip contacts the slinger And a seal member that seals between the outer member and the inner member, so that the end portion of the vertical plate portion is spaced apart from the magnetic encoder toward the seal plate. The wall portion and the magnetic encoder constitute an annular groove on the radially inner side of the seal plate.

  In the wheel bearing device, the labyrinth is configured by bringing the wall portion and the magnetic encoder close to the seal plate.

  In the wheel bearing device, the seal lip includes a radial lip that is in contact with a fitting portion in which the inner member of the slinger is fitted, and an axial lip that is in contact with the standing plate portion. It is composed.

  In the wheel bearing device, a labyrinth slip that extends from the seal plate toward the slinger is formed on the outer side in the radial direction than the axial lip, and the labyrinth is configured by bringing the labyrin slip close to the slinger. .

  As effects of the present invention, the following effects can be obtained.

  That is, according to the present invention, muddy water or the like that has entered the seal member is retained by the annular groove and discharged to the outside before reaching the lip seal. Thereby, the sealing performance can be improved without increasing the rotational torque.

  According to the present invention, entry of muddy water or the like is suppressed by non-contact labyrinths provided at a plurality of locations, and muddy water or the like that has passed through the labyrinth is discharged to the outside by an annular groove. Thereby, the sealing performance can be improved without increasing the rotational torque.

  According to the present invention, muddy water or the like that has passed through the labyrinth is discharged to the outside by the annular groove, so that the muddy water or the like can be prevented from entering only by the axial lip. Thereby, the sealing performance can be improved without increasing the rotational torque.

  According to the present invention, it is difficult for muddy water or the like to reach the lip seal by further providing a labyrinth near the seal lip using the shape of the slinger. Thereby, the sealing performance can be improved without increasing the rotational torque.

The perspective view which shows the whole structure in 1st embodiment of the wheel bearing apparatus which concerns on this invention. Sectional drawing which shows the whole structure in 1st embodiment of the wheel bearing apparatus which concerns on this invention. The expanded end elevation which shows the structure of the seal member in 1st embodiment of the wheel bearing apparatus which concerns on this invention. The expanded end elevation which shows a state when muddy water etc. enter into the sealing member in 1st embodiment of the wheel bearing apparatus which concerns on this invention. The expanded end elevation which shows the sealing member in 2nd embodiment of the wheel bearing apparatus which concerns on this invention. The expanded end elevation which shows the seal member in 3rd embodiment of the wheel bearing apparatus which concerns on this invention.

  Below, the wheel bearing apparatus 1 which is 1st embodiment of the wheel bearing apparatus which concerns on this invention using FIGS. 1-3 is demonstrated.

  As shown in FIGS. 1 and 2, the wheel bearing device 1 supports a wheel rotatably in a suspension device of a vehicle such as an automobile. The wheel bearing device 1 includes an outer ring 2 that is an outer member, a hub ring 3 that is an inner member, an inner ring 4, two rows of inner side balls 5a (see FIG. 2) that are rolling rows, and an outer side ball row. 5b (refer FIG. 2), the inner side sealing member 6, and the outer side sealing member 9 (refer FIG. 2) are comprised. Here, the inner side represents the vehicle body side of the wheel bearing device 1 when attached to the vehicle body, and the outer side represents the wheel side of the wheel bearing device 1 when attached to the vehicle body.

  As shown in FIG. 2, the outer ring 2 which is an outer member supports the hub ring 3 (the hub ring 3 and the inner ring 4). The outer ring 2 is made of medium-high carbon steel containing carbon of 0.40 to 0.80 wt% such as S53C formed in a substantially cylindrical shape. In the outer ring 2, an inner side opening 2 a into which the inner side seal member 6 can be fitted is formed at the inner side end of the outer ring 2 arranged on the vehicle body side when the vehicle is mounted. In the outer ring 2, an outer side opening 2 b into which the outer side seal member 9 can be fitted is formed at an outer side end disposed on the wheel side when the vehicle is mounted.

  On the inner peripheral surface of the outer ring 2, an annular outer side rolling surface 2 c and an outer side outer rolling surface 2 d are formed in parallel to each other in the circumferential direction. The outer rolling surface 2d on the outer side is formed so that the inner side outer rolling surface 2c and the pitch circle diameter are equal or larger. A hardened layer having a surface hardness in the range of 58 to 64 HRC is formed on the inner side outer rolling surface 2c and the outer side outer rolling surface 2d by induction hardening. On the outer peripheral surface of the outer ring 2, a vehicle body attachment flange 2e for attaching to a knuckle of a suspension device (not shown) is integrally formed in the vicinity of the inner side opening 2a.

  The hub wheel 3 constituting the inner member rotatably supports a vehicle wheel (not shown). The hub wheel 3 is made of medium-high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C formed in a bottomed cylindrical shape. In the hub wheel 3, a small-diameter step portion 3a having a reduced diameter on the outer peripheral surface is formed at an inner side end portion disposed on the vehicle body side when the vehicle is mounted. In the hub wheel 3, a wheel mounting flange 3 b for mounting a wheel is integrally formed at an outer side end disposed on the wheel side when the vehicle is mounted. The wheel mounting flange 3b is provided with hub bolts 3d at equal circumferential positions. The hub wheel 3 is disposed such that the inner rolling surface 3 c formed on the outer side faces the outer rolling surface 2 d on the outer side of the outer ring 2.

  The hub wheel 3 is hardened to a surface hardness of 58 to 64 HRC by induction hardening from the inner-side small-diameter step portion 3a to the outer-side inner raceway surface 3c. Thereby, the hub wheel 3 has sufficient mechanical strength against the rotational bending load applied to the wheel mounting flange 3b, and the durability of the hub wheel 3 is improved. The hub wheel 3 is provided with an inner ring 4 at a small diameter step portion 3a. The hub race 3 has an inner raceway surface 4c formed on the outer side with an inner raceway surface 4a formed on the inner race 4 at the inner end facing the outer raceway surface 2c on the inner side of the outer race 2. Is arranged so as to face the outer rolling surface 2d on the outer side of the outer ring 2.

  The inner ring 4 is a rolling train that preloads the inner side ball row 5a disposed on the vehicle body side when mounted on the vehicle and the outer side ball row 5b disposed on the wheel side when mounted on the vehicle. The inner ring 4 is formed in a cylindrical shape. The inner ring 4 is made of high carbon chrome bearing steel such as SUJ2, and is hardened in the range of 58 to 64 HRC to the core part by quenching. On the outer peripheral surface of the inner ring 4, an annular inner rolling surface 4a is formed in the circumferential direction. The inner ring 4 is integrally fixed to the inner side end portion of the hub wheel 3 by caulking while a predetermined preload is applied by press fitting. That is, the inner raceway 4 a is formed by the inner race 4 on the inner side of the hub race 3. The hub race 3 has an inner raceway surface 4c formed on the outer side with an inner raceway surface 4a formed on the inner race 4 at the inner end facing the outer raceway surface 2c on the inner side of the outer race 2. Is arranged so as to face the outer rolling surface 2d of the outer ring 2 on the outer side.

  The inner side ball row 5a and the outer side ball row 5b, which are rolling rows, support the hub wheel 3 rotatably. In the inner side ball row 5a and the outer side ball row 5b, a plurality of balls, which are rolling elements, are held in an annular shape by a cage. The inner side ball row 5a and the outer side ball row 5b are made of high carbon chrome bearing steel such as SUJ2, and are hardened in the range of 58 to 64 HRC up to the core portion by quenching. The inner side ball row 5a is sandwiched between an inner rolling surface 4a formed on the inner ring 4 and an outer rolling surface 2c on the inner side of the outer ring 2 facing the inner rolling surface 4a. The outer side ball row 5b is sandwiched between the inner rolling surface 3c formed on the hub wheel 3 and the outer side rolling surface 2d on the outer side of the outer ring 2 facing the outer rolling surface 3c. . That is, the inner side ball row 5 a and the outer side ball row 5 b support the hub wheel 3 and the inner ring 4 so as to be rotatable with respect to the outer ring 2.

  In the wheel bearing device 1, a double-row angular ball bearing is constituted by an outer ring 2, a hub ring 3, an inner ring 4, an inner side ball row 5a, and an outer side ball row 5b. In the present embodiment, the wheel bearing device 1 is configured with a double-row angular contact ball bearing, but is not limited thereto, and may be configured with a double-row tapered roller bearing or the like.

  As shown in FIGS. 2 and 3, the inner side seal member 6 closes the gap between the inner side opening 2 a of the outer ring 2 and the hub ring 3. The inner side sealing member 6 includes a substantially cylindrical sealing plate 7 and a substantially cylindrical slinger 8.

  As shown in FIG. 3, the seal plate 7 is composed of a core metal and a seal lip. The core metal is made of a ferritic stainless steel plate (JIS standard SUS430 or the like), an austenitic stainless steel plate (JIS standard SUS304 or the like), or a rust-proof cold-rolled steel plate (JIS standard SPCC system or the like). It is configured. The core metal is formed in a substantially L shape in an axial cross-sectional view by bending an outer edge portion of an annular steel plate by press working. As a result, the cored bar includes a cylindrical seal plate fitting portion 7a and an annular lip support portion 7b extending from the end portion toward the axis. A sealing material is vulcanized and bonded to the fitting surface of the seal plate fitting portion 7a. A radial lip 7c, a dust lip 7d and an axial lip 7e are integrally vulcanized and bonded to one side surface of the lip support portion 7b. Radial lip 7c, dust lip 7d and axial lip 7e are NBR (acrylonitrile-butadiene rubber), HNBR (hydrogenated acrylonitrile-butadiene rubber) with excellent heat resistance, EPDM (ethylene propylene rubber), heat resistance, chemical resistance It is composed of excellent synthetic rubber such as ACM (polyacrylic rubber), FKM (fluoro rubber), or silicon rubber. The seal plate 7 is configured integrally with the outer ring 2 with a seal plate fitting portion 7 a fitted into the inner side opening 2 a of the outer ring 2.

  The slinger 8 is made of a steel plate equivalent to the seal plate 7. The slinger 8 is formed in a substantially L shape in an axial cross-sectional view by bending an outer edge portion and an inner edge portion of an annular steel plate by press working. As a result, the slinger 8 includes a cylindrical slinger fitting portion 8a and an annular standing plate portion 8b extending radially outward from the end of the slinger fitting portion 8a. The slinger 8 has a slinger fitting portion 8a fitted to the inner ring 4 and fixed. At this time, the slinger 8 is disposed so that the inner surface of the upright plate portion 8 b faces the lip support portion 7 b of the seal plate 7. A magnetic encoder 8 c is provided on the outer surface of the standing plate portion 8 b of the slinger 8.

  Thus, the inner side seal member 6 is disposed so that the seal plate 7 fitted to the inner side opening 2a of the outer ring 2 and the slinger 8 fitted to the inner ring 4 face each other, thereby constituting a pack seal. doing. The radial lip 7c of the seal plate 7 is in contact with the slinger fitting portion 8a of the slinger 8 through an oil film to prevent the grease inside the wheel bearing device 1 from leaking to the outside. The dust lip 7d of the seal plate 7 is in contact with the outer side (inner side) of the slinger fitting portion 8a than the contact position of the radial lip 7c via an oil film, and from the outside of the wheel bearing device 1 to the inside of dust or the like. Is prevented from entering. Further, the axial lip 7e of the seal plate 7 is in contact with the standing plate portion 8b of the slinger 8 via an oil film to prevent the muddy water and the like from entering the wheel bearing device 1 from the outside. The inner side seal member 6 is configured to be slidable with respect to the slinger 8 when the radial lip 7c, the dust lip 7d and the axial lip 7e of the seal plate 7 contact the slinger 8 via an oil film. Thereby, the inner side sealing member 6 prevents the leakage of the lubricating grease from the inner side opening 2a of the outer ring 2 and the entry of rainwater, dust and the like from the outside.

  As shown in FIG. 2, the outer side sealing member 9 closes the gap between the outer side opening 2 b of the outer ring 2 and the hub ring 3. The outer side seal member 9 is configured as an integral seal in which a seal lip is vulcanized and bonded to a substantially cylindrical cored bar.

  The core of the outer side seal member 9 is made of a ferritic stainless steel plate (JIS standard SUS430 or the like), an austenitic stainless steel plate (JIS standard SUS304 or the like), or a rust-proof cold rolled steel plate (JIS standard). SPCC system etc.). The core metal is formed in a substantially L shape in an axial cross-sectional view by bending an outer edge portion of an annular steel plate by press working. The seal lip is NBR (acrylonitrile-butadiene rubber), HNBR (hydrogenated acrylonitrile-butadiene rubber) excellent in heat resistance, EPDM (ethylene propylene rubber), ACM (polyacrylic rubber) excellent in heat resistance and chemical resistance, It is made of synthetic rubber such as FKM (fluoro rubber) or silicon rubber.

  The outer side seal member 9 has a core metal fitted into the outer side opening 2 b of the outer ring 2. At this time, the outer side seal member 9 is arranged so that the seal lip contacts the seal sliding surface of the hub wheel 3. The outer side seal member 9 is configured to be slidable with respect to the seal sliding surface when the seal lip contacts the seal sliding surface of the hub wheel 3 through the oil film. Thereby, the seal lip of the outer side seal member 9 prevents leakage of lubricating grease from the outer side opening 2b of the outer ring 2 and entry of rainwater, dust, and the like from the outside.

  The wheel bearing device 1 configured as described above includes an outer ring 2, a hub ring 3, an inner ring 4, an inner side ball row 5a, and an outer side ball row 5b to form a double row angular ball bearing. 4 is rotatably supported by the outer ring 2 via an inner side ball row 5a and an outer side ball row 5b. In the wheel bearing device 1, the gap between the inner side opening 2 a of the outer ring 2 and the inner ring 4 is closed by the inner side seal member 6, and the gap between the outer side opening 2 b of the outer ring 2 and the hub ring 3 is closed. The outer side sealing member 9 is closed. As a result, in the wheel bearing device 1, the hub ring 3 and the inner ring 4 supported by the outer ring 2 rotate while preventing leakage of lubricating grease from the inside and entry of rainwater, dust, and the like from the outside.

  Next, the slinger 8 constituting the inner side seal member 6 will be described in detail with reference to FIG. The slinger 8 includes a cylindrical slinger fitting portion 8a and an annular standing plate portion 8b extending radially outward from an end portion of the slinger fitting portion 8a. The slinger 8 is disposed so that the upright plate portion 8 b faces the lip support portion 7 b of the seal plate 7.

  As shown in FIG. 3, a wall portion 8 d is formed at the radial end portion of the standing plate portion 8 b of the slinger 8. The wall portion 8d includes a cylindrical portion extending by a predetermined amount W in the axial direction from the radial end portion of the upright plate portion 8b toward the inside of the wheel bearing device 1, and a circle extending radially outward from the tip of the cylindrical portion. And an annular plate portion. That is, a wall portion 8d that is an annular step that is recessed toward the inside of the wheel bearing device 1 by a predetermined amount W is formed at the radial end portion of the upright plate portion 8b. . The annular plate portion of the wall 8d is provided as a partition plate extending radially outward at a position shifted by a predetermined amount W in the axial direction from the radial end of the standing plate 8b. The annular plate portion of the wall 8d is formed so as to be close to the seal plate fitting portion 7a of the seal plate 7 with a slight gap. Thereby, the inner side seal member 6 is provided between the wall portion 8d which is the side wall of the annular groove 10 and the seal plate fitting portion 7a of the seal plate 7 which is radially opposed to each end portion of the magnetic encoder 8c. A labyrinth 11 is configured. In the present embodiment, the wall portion 8d is formed such that the radial end portion of the upright plate portion 8b is bent in a cylindrical shape toward the inside of the wheel bearing device 1 and is directed radially outward at a predetermined amount W. By being bent, it is formed integrally with the upright plate portion 8b.

  A magnetic encoder 8c is provided on the outer surface of the standing plate portion 8b of the slinger 8 (thin thin ink portion). The magnetic encoder 8c is fixed only to the outer surface of the upright plate portion 8b. Furthermore, the magnetic encoder 8c is formed with an annular plate portion that extends radially outward from the end of the upright plate portion 8b. The annular plate portion of the magnetic encoder 8c is configured as a partition plate extending radially outward from the radial end of the upright plate portion 8b. The annular plate portion of the magnetic encoder 8 c is formed so as to be close to the seal plate fitting portion 7 a of the seal plate 7 with a slight gap. Thus, the labyrinth 11 is configured between the annular plate portion of the magnetic encoder 8 c that is the side wall of the annular groove 10 and the seal plate fitting portion 7 a of the seal plate 7 in the inner side seal member 6.

  The slinger 8 is a state in which the annular plate portion of the magnetic encoder 8c fixed to the standing plate portion 8b and the annular portion of the wall portion 8d formed integrally with the standing plate portion 8b are separated by a predetermined amount W. Are arranged so as to face each other. As a result, an annular groove 10 having an annular plate portion of the magnetic encoder 8c and an annular plate portion of the wall portion 8d as side walls and a cylindrical portion of the wall portion 8d as a bottom surface is formed at the radial end portion of the slinger 8. The seal plate 7 is configured on the radially inner side. Further, the slinger 8 is arranged so that the annular plate portion of the magnetic encoder 8 c constituting the side wall of the annular groove 10 and the annular plate portion of the wall portion 8 d are close to the seal plate fitting portion 7 a of the side wall seal plate 7. Is formed. That is, the annular plate portion of the magnetic encoder 8c is configured as a partition plate extending radially outward from the radial end of the upright plate portion 8b. Thereby, the labyrinth 11 is comprised in the inner side sealing member 6 between each side wall of the annular groove 10, and the sealing plate fitting part 7a of the sealing plate 7. FIG.

With this configuration, the inner side seal member 6 of the wheel bearing device 1 has a wall portion 8d in which the radial end portion of the standing plate portion 8b of the slinger 8 is separated from the magnetic encoder 8c by a predetermined amount W. An annular groove 10 having a predetermined width W is formed from the magnetic encoder 8c. Further, in the inner side seal member 6, a labyrinth 11 is formed between the seal plate fitting portion 7 a of the seal plate 7 and each side wall of the annular groove 10.
Therefore, as shown in FIG. 4, in the wheel bearing device 1, the labyrinth 11 suppresses the entry of muddy water or the like, and muddy water or the like (see the black arrow) that enters the seal member reaches the lip seal. Up to this point, it is fastened by the annular groove 10 and discharged to the outside of the inner side seal member 6. Thereby, the wheel bearing device 1 can improve the sealing performance without increasing the rotational torque.

  In the present embodiment, the annular groove 10 is an annular step in which the radial end portion of the upright plate portion 8b is recessed toward the inside of the wheel bearing device 1 by a predetermined amount W over the entire circumference. Although it is comprised from the certain wall part 8d, it is not limited to this, The magnetic encoder 8c and the radial direction edge part of the standing board part 8b should just be formed so that it may space apart.

  Next, a wheel bearing device 12 that is a second embodiment of the wheel bearing device according to the present invention will be described with reference to FIG. In addition, the wheel bearing devices 12 and 13 according to the following embodiments are used in the description as being applied in place of the wheel bearing device 1 in the wheel bearing device 1 shown in FIGS. 1 to 4. By using names, figure numbers, and symbols, the same thing is pointed out, and in the following embodiments, specific explanations are omitted with respect to the same points as the embodiments already described, and different parts are mainly described. To do.

  As shown in FIG. 5, a radial lip 7 c and an axial lip 7 e are integrally vulcanized and bonded to one side surface of the lip support portion 7 b of the seal plate 7. The seal plate 7 is configured integrally with the outer ring 2 with a seal plate fitting portion 7 a fitted into the inner side opening 2 a of the outer ring 2. The radial lip 7c contacts the slinger fitting portion 8a of the slinger 8 through an oil film, and prevents the grease inside the wheel bearing device 12 from leaking to the outside. The axial lip 7e of the seal plate 7 is in contact with the standing plate portion 8b of the slinger 8 via an oil film, and prevents the muddy water or the like from entering the wheel bearing device 12 from the outside. The inner side sealing member 6 is configured to be slidable with respect to the slinger 8 when the radial lip 7c and the axial lip 7e contact the slinger 8 through the oil film. Thereby, the inner side sealing member 6 prevents the leakage of the lubricating grease from the inner side opening 2a of the outer ring 2 and the entry of rainwater, dust and the like from the outside.

  With such a configuration, the labyrinth 11 is formed between the annular groove 10 and each side wall of the annular groove 10 in the inner seal member 6 of the wheel bearing device 12. Accordingly, the wheel bearing device 12 is prevented from entering muddy water or the like by the plurality of labyrinths 11 and is retained by the annular groove 10 until the muddy water or the like entering the seal member reaches the lip seal. Since it is discharged to the outside of the side seal member 6, entry of muddy water or the like is prevented only by the axial lip 7e. Thereby, since the bearing device 12 for wheels does not need to provide a dust lip, the sealing performance can be improved without increasing the rotational torque.

  Next, a wheel bearing device 13 that is a third embodiment of the wheel bearing device according to the present invention will be described with reference to FIG.

  As shown in FIG. 6, a radial lip 7c, an axial lip 7e, and a labyrinth slip 7f are integrally vulcanized and bonded to one side surface of the lip support portion 7b of the seal plate 7. The seal plate 7 is configured integrally with the outer ring 2 with a seal plate fitting portion 7 a fitted into the inner side opening 2 a of the outer ring 2. The radial lip 7c is in contact with the slinger fitting portion 8a of the slinger 8 through an oil film, and prevents leakage of grease inside the wheel bearing device 13 to the outside. The axial lip 7e of the seal plate 7 is in contact with the standing plate portion 8b of the slinger 8 via an oil film, and prevents the muddy water and the like from entering from the outside of the wheel bearing device 13. The labyrinth slip 7 f of the seal plate 7 constitutes a labyrinth without contacting the slinger 8 and prevents the muddy water or the like from entering the inside of the wheel bearing device 13. The labyrinth slip 7 f is disposed on the radially outer side than the axial lip 7 e and is formed so as to be close to the slinger 8 from the seal plate 7. The labyrinth slip 7f is formed so as to be close to the standing plate portion 8b or the wall portion 8d of the slinger 8 with a slight gap between the labyrinth slip 7f. That is, the labyrinth slip 7 f constitutes the labyrinth 14 by being close to the standing plate portion 8 b or the wall portion 8 d of the slinger 8.

  With this configuration, the labyrinth 11 is configured between the annular groove 10 and each side wall of the annular groove 10 in the inner seal member 6 of the wheel bearing device 13. Furthermore, the labyrinth 14 is comprised in the inner side seal member 6 by the labyrinth slip 7f arrange | positioned between the labyrinth 11 of the annular groove 10, and the axial lip 7e. Therefore, in the wheel bearing device 13, the plurality of labyrinths 11 and the labyrinth 14 prevent muddy water or the like from entering the wheel bearing device 13. Moreover, the inner side sealing member 6 is arrange | positioned so that the labyrinth slip 7f may overlap with the wall part 8d by radial direction view. That is, the labyrinth slip 7f is disposed so as to cover the axial lip 7e. Thereby, even if muddy water overflows from the annular groove 10, the wheel bearing device 13 is excluded by the labyrinth slip 7f. Thereby, since the wheel bearing device 13 does not need to be provided with a dust lip, the sealing performance can be improved without increasing the rotational torque.

  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. In the present embodiment, the wheel bearing device 1, 12, 13 is a third-generation wheel bearing device in which the inner raceway surface 3 c of the inner side ball row 5 a is directly formed on the outer periphery of the hub wheel 3. However, the present invention is not limited to this, and a second generation structure in which a pair of inner rings are press-fitted and fixed to the hub wheel 3 may be used.

DESCRIPTION OF SYMBOLS 1 Wheel bearing apparatus 2 Outer ring 2a Inner side opening 3 Hub ring 4 Inner ring 5a Inner side ball row 5b Outer side ball row 6 Seal member 7 Seal plate 8 Slinger 8b Standing plate portion 8c Magnetic encoder 8d Wall portion 10 Ring groove

Claims (4)

An outer member in which a double row outer rolling surface is integrally formed on the inner periphery;
A double row comprising a hub wheel having a small-diameter step portion extending in the axial direction on the outer periphery and at least one inner ring press-fitted into the small-diameter step portion of the hub wheel, and facing the outer rolling surface of the double row on the outer periphery. An inward member formed with an inner rolling surface of
A double row rolling element housed movably between the rolling surfaces of the inner member and the outer member;
A seal plate is fitted into the opening of the outer member, and a slinger having a standing plate portion extending radially outward is fitted to the outer peripheral portion of the inner member so as to face the seal plate, and the seal At least one seal lip made of an elastic body is provided on the plate, a magnetic encoder is provided on the outer surface of the standing plate portion of the slinger, and the outer member and the inner member are brought into contact with the slinger by the seal lip. A wheel bearing device comprising: a seal member that seals between
A wall portion that is spaced from the magnetic encoder and extends toward the seal plate is formed at an end of the standing plate portion,
A wheel bearing device in which an annular groove is formed radially inward of the seal plate by the wall portion and the magnetic encoder.   The wheel bearing device according to claim 1, wherein a labyrinth is configured by bringing the wall portion and the magnetic encoder close to the seal plate.   The said seal lip is comprised from the radial lip which is contacting the fitting part to which the said inward member is fitted among the said slinger, and the axial lip which is contacting the said standing board part. The wheel bearing device according to claim 2.   4. The wheel bearing device according to claim 3, wherein a labyrinth slip extending from the seal plate toward the slinger is formed on a radially outer side than the axial lip, and the labyrinth is configured by bringing the labyrin slip close to the slinger. .

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