JP5676289B2 - Wheel bearing device - Google Patents

Description

  The present invention relates to a wheel bearing device for rotatably supporting a wheel of an automobile or the like, and more particularly to a wheel bearing device with improved sealing performance.

  2. Description of the Related Art Conventionally, a wheel bearing device for supporting a wheel of an automobile or the like is such that a hub wheel for mounting a wheel is rotatably supported via a rolling bearing, and there are 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. As the wheel bearing device, a double-row angular ball bearing having a desired bearing rigidity, exhibiting durability against misalignment, and having a small rotational torque from the viewpoint of improving fuel efficiency is often used. On the other hand, double row tapered roller bearings are used in vehicles such as off-road cars and trucks that have a heavy vehicle body weight.

  Since these wheel bearing devices are arranged at sites where muddy water or the like is easily applied, a seal device is mounted to seal between the outer member and the inner member. Generally, in a sealing device, a sealing member having a sealing lip is attached to an outer member serving as a stationary member, and the sealing lip is slidably contacted with an outer peripheral surface of the inner member.

  An example of the sealing device in such a wheel bearing device is shown in FIG. A metal ring 51 is fitted on the base 50 a of the wheel mounting flange 50, and the seal 52 is disposed so as to be in sliding contact with the metal ring 51. The seal 52 includes a cored bar 54 fitted to the inner periphery of the end of the outer member 53 and a seal member 55 integrally joined to the cored bar 54 by vulcanization adhesion or the like.

  The seal member 55 is joined to the outer peripheral portion of the cored bar 54, joined to a pair of side lips 55a and 55b extending obliquely outward in the radial direction, and the inner edge of the cored bar 54, and tilted to the bearing inward side. And a grease lip 55c extending.

  The metal ring 51 is formed by press working from an austenitic stainless steel plate or the like having corrosion resistance, and a cylindrical fitting portion 51a that is externally fitted to the shoulder portion 56a of the hub wheel 56, and a base portion 50a that is formed in an arc shape. Corresponding to the curved portion 51b, a circular portion 51c extending radially outward from the curved portion 51b and in close contact with the side surface 50b of the wheel mounting flange 50, and the circular portion 51c. A cylindrical umbrella portion 51d extending away from the outer diameter portion in the axial direction with respect to the wheel mounting flange 50, and a bent portion 51e formed to protrude radially outward from the umbrella portion 51d are provided. .

  The base portion 50 a is formed in an arc surface having a predetermined radius of curvature r at a corner portion between the shoulder portion 56 a of the hub wheel 56 and the wheel mounting flange 50. Corresponding to this arc surface, the curved portion 51b of the metal ring 51 is formed of an arc surface having a predetermined radius of curvature R, and the respective curvature radii R and r are set such that R ≧ r. This prevents the curved portion 51b of the metal ring 51 from interfering with the circular arc surface of the base portion 50a when the metal ring 51 is fitted to the base portion 50a.

  The umbrella portion 51d of the metal ring 51 is disposed so as to face the outer periphery of the outer member 53 via a slight annular gap A, thereby forming a labyrinth seal. The annular gap A is set in a range of 0.05 to 1.0 mm (diameter). A plurality of drain holes 57 are formed in the circumferential direction of the umbrella portion 51d.

  As described above, the labyrinth effect formed by the inner peripheral surface of the umbrella portion 51d and the outer peripheral surface of the outer member 53 prevents muddy water from entering the sliding contact portion between the seal 52 and the metal ring 51. Even if muddy water or the like enters the inside of the metal ring 51 from this slight annular gap A, as shown by the arrow in the figure, it is discharged by the centrifugal force accompanying the rotation of the metal ring 51, The drain hole 57 formed in the umbrella portion 51d is easily discharged to the outside and does not stay on the side lip 55a. Therefore, muddy water or the like can be prevented from adhering to the sliding contact surface of the side lip 55a and worn, and a stable sealing performance can be maintained over a long period of time.

  Further, when the vehicle is stopped, the muddy water or the like that has entered the metal ring 51 flows downward through the side lip 55a of the seal 52, and is a drainage hole formed below the umbrella portion 51d closest to the road surface. It is discharged from 57.

  Further, a slinger 58 is press-fitted into the outer periphery of the end portion of the outer member 53. The slinger 58 includes a cylindrical portion 58a that is press-fitted in the vicinity of the end of the metal ring 51, and a standing plate portion 58b that extends radially outward from the cylindrical portion 58a. Is formed in a substantially L-shape. And the bending part 51e of the metal ring 51 and the standing board part 58b oppose via the slight axial gap B, and the labyrinth seal is comprised.

  Thereby, the muddy water entering the outer peripheral surface of the outer member 53 is blocked by the slinger 58, and the muddy water is prevented from entering the metal ring 51, and the labyrinth seal is used to Since the muddy water that has entered does not hinder the discharge due to the centrifugal force associated with the rotation of the metal ring 51, stable sealing performance can be maintained over a long period of time (see, for example, Patent Document 1).

JP 2010-53893 A

  In such a sealing device for a conventional wheel bearing device, a metal ring 51 is disposed between the seal 52 mounted on the outer member 53 and the hub wheel 56 to prevent rust on the sliding surface of the seal lip. In addition, a slinger 58 is disposed on the outer peripheral surface of the outer member 53 to prevent foreign matter from entering from the gap between the hub wheel 56 and the outer member 53, thereby improving the sealing performance. However, the main purpose of this seal structure is to prevent foreign matter from entering from the outside. When lubricating grease or oil leaks from the inside of the bearing, the leaked grease or oil or the like travels through the metal ring 51 by centrifugal force. May be scattered outside the bearing. In this case, brake parts are arranged on the outer side of the bearing, and if grease, oil, or the like scatters, there is a risk that the brake performance will be affected.

  This invention is made | formed in view of such a situation, and aims at the improvement of the sealing performance of a seal | sticker, and it aims at providing the wheel bearing apparatus which can maintain bearing performance over a long period of time. .

In order to achieve such an object, the invention according to claim 1 of the present invention includes an outer member integrally including a vehicle body mounting flange on the outer periphery and a double row outer rolling surface formed integrally on the inner periphery. A wheel mounting flange for mounting the wheel at one end, and an inner rolling surface facing one of the double row outer rolling surfaces on the outer periphery, and a small diameter extending in the axial direction from the inner rolling surface. A hub ring formed with a stepped portion, and a small diameter stepped portion of the hub ring are press-fitted through a predetermined shimeshiro, and an inner rolling surface facing the other of the outer rolling surfaces of the double row is formed on the outer periphery. An inner member composed of an inner ring, a double row rolling element which is accommodated between the rolling surfaces of the inner member and the outer member via a cage, and the outer member and the inner member. A seal mounted in an opening of an annular space formed between the member and the outer of these seals The side seal is fitted to the inner periphery of the end of the outer member, the side lip is integrally joined to the core and extends obliquely outward in the radial direction, and is inclined toward the bearing inward side. In the wheel bearing device constituted by a one-piece seal composed of a seal member having a grease lip extending in this manner, a slinger is mounted on the outer periphery of the outer end of the outer member, and the slinger has corrosion resistance. A cylindrical fitting portion formed by pressing from a steel plate and press-fitted into the outer periphery of the end portion of the outer member, an annular groove portion extending radially outward from the fitting portion, and a road surface of the annular groove portion The closest portion is constituted by a pocket portion formed by expanding a part of the fitting portion, and extends in the axial direction from the pocket portion along the outer peripheral surface of the outer member, on the side facing the outer circumferential surface of the outer member Trough having a discharge portion are integrally formed, the trough is arranged in a portion avoiding the vehicle body mounting flange of the outer member, the distal end portion of the trough portion is open to the inner side of the vehicle body mounting flange It is set to be.

In this way, a slinger is mounted on the outer periphery of the outer member on the outer side, and this slinger is formed by pressing from a corrosion-resistant steel plate and is pressed into the outer periphery of the outer member. A fitting portion, an annular groove portion extending radially outward from the fitting portion, and a pocket portion formed by expanding a part of the fitting portion at a portion closest to the road surface of the annular groove portion. In addition to being configured, a hook portion extending in the axial direction along the outer peripheral surface of the outer member from the pocket portion and having an open portion on the side facing the outer peripheral surface of the outer member is integrally formed. Grease that has been leaked through the seal because it is arranged in the part of the outer member that avoids the body mounting flange, and the tip of the flange is set to open to the inner side of the body mounting flange. Or oil is scattered by centrifugal force Even if it is collected by the annular groove portion and flows out to the road surface side, the grease or oil that has flowed out can be collected by this pocket portion and discharged to the outside through the flange portion extending from the pocket portion to the inner side. . Therefore, the scattered grease or oil does not adhere to the brake parts, and it is possible to reliably prevent the brake performance from being affected.

  Preferably, as in the invention described in claim 2, a base portion on the inner side of the wheel mounting flange is formed in an arc shape, and a metal ring formed by pressing from a steel plate is fitted to the base portion. The metal ring includes a cylindrical fitting portion that is fitted on the shoulder portion of the hub wheel, a curved portion that is formed in an arc shape corresponding to the shape of the base portion, and a radially outer portion from the curved portion. And a disc portion that is in close contact with the inner side surface of the wheel mounting flange, and if at least a side lip of the seal member is in sliding contact with the metal ring, a good seal sliding contact surface is obtained. Thus, the lip wear can be suppressed and the sealing performance of the seal can be maintained even when used in a poor environment.

  According to a third aspect of the present invention, the base portion is formed on an arc surface having a predetermined radius of curvature r, and the curved portion of the metal ring corresponding to the arc surface has a predetermined radius of curvature R. If the radius of curvature R and r are set so that R ≧ r, the curved portion of the metal ring interferes with the arc surface of the base when the metal ring is fitted to the base. Therefore, it is possible to prevent floating, and it is possible to prevent a gap from being generated between the side surface of the wheel mounting flange and the disk portion of the metal ring. As a result, both can be in close contact with each other to suppress the unevenness of the side lip and to ensure stable sealing.

  Moreover, if the said metal ring is formed with the steel plate which has corrosion resistance like the invention of Claim 4, and the surface roughness of the steel plate used as the raw material is set to the range of Ra0.2-0.6. Can prevent rusting over a long period of time, maintain sealing performance, obtain a good seal sliding contact surface, suppress lip wear, and seal even if used in a poor environment The sealing performance can be maintained.

According to a fifth aspect of the present invention, the metal ring includes a bent portion that is spaced apart from the outer diameter portion of the disk portion with respect to the wheel mounting flange and that extends obliquely outward in the radial direction. If provided, the scattered grease or oil can be effectively collected in the annular groove.

  Further, as in the invention according to claim 6, the annular groove portion of the slinger includes a standing plate portion extending in the radial direction from the fitting portion, a cylindrical bottom portion extending in the axial direction from the standing plate portion, A labyrinth seal, and an inner diameter of the edge is set to be slightly larger than an outer diameter of the disk portion of the metal ring. If the grease or oil leaked from the seal is scattered by the centrifugal force accompanying the rotation of the metal ring, it can be collected by this annular groove and allowed to flow out to the road surface side.

  In addition, as in the invention described in claim 7, if a flange portion bent outward in the radial direction is formed at an end portion of the fitting portion of the slinger, the slinger is improved in rigidity and the slinger is The press-fit property to the outer member can be improved.

  Further, as in the invention according to claim 8, if the edge of the annular groove is formed of synthetic rubber integrally joined to the slinger by vulcanization adhesion, the inner diameter is larger than the outer diameter of the metal ring. Even if it is set to a small diameter, the edge portion can be elastically deformed during assembly to overcome the metal ring, so that both can be assembled without hindering the assembly work.

  Further, as in the invention described in claim 9, a side wall is formed to rise radially outward from a base portion on the inner side of the wheel mounting flange, and a slight axial clearance is provided between an end surface on the outer side of the outer member and a slight axial clearance. If the labyrinth seal is formed, the inner diameter of the edge of the slinger is set to be slightly larger than the outer diameter of the side wall, and the labyrinth seal is formed, Even if the leaked grease or oil is scattered by the centrifugal force accompanying the rotation of the hub wheel, it can be collected by this annular groove and drained to the road surface side, and foreign matter such as muddy water can enter the seal area from the outside. Can be prevented, and the sealing performance of the seal can be improved.

  Further, as in the invention described in claim 10, the outer member is fixed to the axle tube supported on the lower surface of the vehicle body, and a serration is formed on the inner periphery of the hub wheel, If the hollow drive shaft is connected so that torque can be transmitted and a cap is press-fitted into the opening of the outer end of the hub wheel, the diff oil will flow out to the outside, and rainwater, dust, etc. Can be reliably prevented from entering the differential oil.

A wheel bearing device according to the present invention has a vehicle body mounting flange integrally formed on the outer periphery, an outer member integrally formed with a double row outer rolling surface on the inner periphery, and a wheel for mounting a wheel on one end. A hub wheel integrally having a wheel mounting flange and having an inner rolling surface facing one of the outer rolling surfaces of the double row on the outer periphery and a small-diameter step portion extending in the axial direction from the inner rolling surface, And an inner member formed of an inner ring that is press-fitted into a small-diameter step portion of the hub ring through a predetermined shimoshiro and has an inner rolling surface facing the other of the outer rolling surfaces of the double row on the outer periphery, A double row rolling element housed between a rolling surface of the inner member and the outer member via a cage, and a ring formed between the outer member and the inner member. A seal mounted on the opening of the space, and the outer seal of these seals is the outer portion. A seal having a core metal fitted to the inner periphery of the end, a side lip integrally joined to the core metal and extending obliquely outward in the radial direction, and a grease lip extending inclined toward the inner side of the bearing In the wheel bearing device composed of an integral seal made of a member, a slinger is attached to the outer periphery of the outer side end of the outer member, and the slinger is formed from a corrosion-resistant steel plate by pressing, A cylindrical fitting portion press-fitted into the outer periphery of the end portion of the outer member, an annular groove portion extending radially outward from the fitting portion, and a portion closest to the road surface of the annular groove portion, the fitting portion And a pocket portion formed by expanding a part of the outer diameter of the outer member. The pocket portion extends in the axial direction along the outer peripheral surface of the outer member and faces the outer peripheral surface of the outer member. in the gutter portion having an opening on the side is integrally Formed, the flange is disposed in a portion of the outer member that avoids the vehicle body mounting flange, and the distal end of the flange is set to open to the inner side of the vehicle body mounting flange. Even if grease or oil leaked through the seal is scattered by centrifugal force, the grease or oil is collected in the annular groove and flows out to the road surface side. It can be discharged to the outside through a flange extending to the side. Therefore, the scattered grease or oil does not adhere to the brake parts, and it is possible to reliably prevent the brake performance from being affected.

It is a longitudinal section showing one embodiment of a wheel bearing device concerning the present invention. It is a principal part enlarged view which shows one seal part of FIG. It is a principal part enlarged view which shows the other seal part of FIG. It is a principal part enlarged view which shows the modification of FIG. (A), (b), (c) is sectional drawing which shows the modification of a slinger. It is a longitudinal cross-sectional view which shows the road surface side of the bearing apparatus for wheels of FIG. (A) is a front view which shows the slinger simple substance of FIG. 3, (b) is a top view of (a), (c) is a side view of (a). It is a principal part enlarged view which shows the modification of FIG. It is a principal part enlarged view which shows the modification of FIG. It is a principal part enlarged view which shows the other modification of FIG. FIG. 9 is an enlarged view of a main part showing another modification of FIG. 3. It is a principal part enlarged view which shows the sealing device of the conventional wheel bearing apparatus.

An outer member integrally having a vehicle body mounting flange to be attached to the axle tube on the outer periphery, a double row outer rolling surface formed integrally on the inner periphery, and a wheel mounting flange for attaching a wheel to one end And a hub wheel in which an inner rolling surface facing one of the double row outer rolling surfaces and a small-diameter step portion extending in the axial direction from the inner rolling surface are formed on the outer periphery, and the hub An inner member comprising an inner ring press-fitted into a small-diameter step portion of the ring via a predetermined squeezing and having an inner rolling surface facing the other of the outer rolling surfaces of the double row on the outer periphery, and the inner member And a double row rolling element housed between the rolling surfaces of the outer member via a cage, and an opening in an annular space formed between the outer member and the inner member A metal ring fitted on the inner base of the wheel mounting flange. In addition, the outer seal of the seal is a cored bar fitted to the inner periphery of the end of the outer member, and is integrally joined to the cored bar, extending in a radially outward direction, In a wheel bearing device comprising an integrated seal comprising a seal member having a side lip that is slidably contacted with a metal ring and a grease lip that extends obliquely toward the inner side of the bearing, the outer side of the outer member A slinger is attached to the outer periphery of the end of the cylinder, and the slinger is formed by press working from a corrosion-resistant steel plate and is press-fitted into the outer periphery of the end of the outer member. An annular groove portion extending radially outward from a pocket portion and a pocket portion formed by enlarging a part of the fitting portion at a portion closest to the road surface of the annular groove portion. From the outer periphery of the outer member Extending axially along the, trough having an open portion on the side facing the outer circumferential surface of the outer member are integrally formed, distribution in the portion the trough portion is to avoid the vehicle body mounting flange of the outer member It is provided and the front-end | tip part of the said collar part is set so that it may open to an inner side rather than this vehicle body attachment flange.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a longitudinal sectional view showing an embodiment of a wheel bearing device according to the present invention, FIG. 2 is an enlarged view of a main part showing one seal part of FIG. 1, and FIG. 3 is the other seal of FIG. 4 is an enlarged view of a main part showing a modification of FIG. 3, FIGS. 5A, 5B, and 5C are sectional views showing a modification of the slinger, FIG. FIG. 7 is a longitudinal sectional view showing the road surface side of the wheel bearing device of FIG. 1, FIG. 7A is a front view showing the slinger alone of FIG. 3, FIG. 7B is a plan view of FIG. FIG. 8 is a side view of FIG. 8A, FIG. 8 is an enlarged view of a main part showing a modification example of FIG. 3, FIG. 9 is an enlarged view of a main part showing a modification example of FIG. The principal part enlarged view which shows a modification, FIG. 11 is the principal part enlarged view which shows the other modification of FIG. 3 same as the above. 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).

  This wheel bearing device is fixed to the axle tube H and connected to the drive shaft D / S so as to be able to transmit torque. This wheel bearing device is referred to as a third generation, and includes an inner member 1 and an outer member 2 inserted on the inner member 1 via double-row rolling elements (balls) 3. . The inner member 1 includes a hub ring 4 and an inner ring 5 fixed to the hub ring 4.

  The hub wheel 4 integrally has a wheel mounting flange 6 for mounting a wheel (not shown) at an end portion on the outer side, and has one (outer side) inner rolling surface 4a on the outer periphery and the inner rolling surface. A small diameter step portion 4b extending in the axial direction from the surface 4a is formed, and a serration (or spline) 4c with which the drive shaft D / S engages is formed on the inner periphery. Hub bolts 6a are planted on the wheel mounting flange 6 at equal intervals in the circumferential direction.

  The inner ring 5 is formed with the other (inner side) inner rolling surface 5a on the outer periphery, and is press-fitted into the small-diameter step portion 4b of the hub wheel 4 through a predetermined shimiro, and the end portion of the small-diameter step portion 4b is radially outward. It is fixed to the hub wheel 4 in the axial direction in a state where a predetermined bearing preload is applied by a caulking portion 4d formed by plastic deformation in the direction.

  The hub wheel 4 is formed of medium and high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and the inner raceway surface 4a and the base portion 6b on the inner side of the wheel mounting flange 6 are connected to the small diameter step portion 4b. Thus, the surface hardness is set to a range of 58 to 64 HRC by induction hardening. The caulking portion 4d is an unquenched portion with the surface hardness after forging. This has sufficient mechanical strength against the rotational bending load applied to the wheel mounting flange 6, improves the fretting resistance of the small-diameter stepped portion 4b serving as the fitting portion of the inner ring 5, and performs caulking. A micro crack or the like is prevented from occurring in the caulking portion 4d due to the processing.

  The outer member 2 integrally has a vehicle body mounting flange 2b to be attached to the axle tube H on the outer periphery, and a double row of inner rows facing the double rolling inner rolling surfaces 4a and 5a of the inner member 1 on the inner periphery. The outer rolling surfaces 2a and 2a are integrally formed. The outer member 2 is formed of medium-high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and at least the double row outer rolling surfaces 2a and 2a have a surface hardness of 58 to 64 HRC by induction hardening. Hardened to range. On the other hand, the inner ring 5 and the rolling element 3 are made of high carbon chrome steel such as SUJ2, and are hardened in the range of 58 to 64 HRC up to the core portion by quenching. And the double row rolling elements 3 and 3 are accommodated between both rolling surfaces of the outer member 2 and the inner member 1, and are held by the cages 7 and 7 so as to roll freely. A ball bearing is configured.

  Seals 8 and 9 are attached to the opening of the annular space formed between the outer member 2 and the inner member 1. These seals 8 and 9 prevent the grease sealed inside the bearing from leaking outside and preventing rainwater, dust, and the like from entering the bearing from the outside. The inner seal 9 prevents the differential oil from entering the bearing through the serrations 4 c of the hub wheel 4.

  A cap 10 is press-fitted into the opening at the end on the outer side of the hub wheel 4. The cap 10 is made of an austenitic stainless steel plate (JIS standard SUS304 type or the like) or a rust-proof cold-rolled steel plate (JIS standard SPCC type or the like), and is formed in an annular shape by press working. The cap 10 is composed of a steel plate core 10a having a substantially U-shaped cross section, and an elastic member 10b such as rubber joined to at least a fitting portion of the core 10a by vulcanization adhesion or the like. The elastic member 10b is elastically deformed and enters the fitting surface to seal the inside in a liquid-tight manner. Therefore, the outflow of the differential oil to the outside, and rain water, dust, etc. from the outside can be reliably prevented from entering the drive shaft D / S and mixing into the differential oil. A retaining ring 11 prevents the cap 10 from moving to the outer side and falling off.

  As shown in an enlarged view in FIG. 2, the inner side seal 9 includes an annular seal plate 12 fitted to the outer periphery of the end portion of the outer member 2, and an annular pulsar ring 13 fitted to the outer periphery of the inner ring 5. Consists of. The seal plate 12 includes a cored bar 14 made of a magnetic material having excellent corrosion resistance such as an austenitic stainless steel plate, a ferritic stainless steel plate (JIS standard SUS430 series, etc.), a rust-proof cold rolled steel plate, and the like. A seal member comprising radial lips 15a and 15b that are in sliding contact with or close to the outer periphery of the shaft 5 and side lips 15c that extend inward in the radial direction and contact the side wall of the axle tube H via a predetermined axial nip. 15 and an elastic lip 15d that contacts the inner wall of the axle tube H via a predetermined radial shimoshiro.

  The cored bar 14 is a cylindrical fitting part 14a that is press-fitted into the outer periphery of the end part of the outer member 2, and extends radially inward from the fitting part 14a, and is attached to the inner end face 2c of the outer member 2. The seal member 15 includes an intimate flange portion 14b, a cylindrical portion 14c extending in the axial direction from the flange portion 14b, and an inner diameter portion 14d extending inwardly in the radial direction from the cylindrical portion 14c, and the seal member 15 is made of NBR (acrylonitrile). It is made of synthetic rubber such as (butadiene rubber) and is joined to the inner diameter portion 14d. Here, the radial lips 15a and 15b of the seal member 15 prevent the lubricating grease sealed inside the bearing from flowing out and the differential oil from entering the inside of the bearing, and the seal lip 15c prevents the differential oil from entering the outside of the bearing. Leakage and rainwater and dust are prevented from entering the device from the outside. As the material of the seal member 15, in addition to the exemplified NBR, for example, HNBR (hydrogenated acrylonitrile butadiene rubber), EPDM (ethylene propylene rubber), etc. having excellent heat resistance, heat resistance, chemical resistance, etc. Examples thereof include ACM (polyacrylic rubber), FKM (fluororubber), and silicon rubber, which are excellent in the above.

  The pulsar ring 13 includes a holding plate 13a and a magnetic encoder 13b vulcanized and bonded to the outer periphery of the holding plate 13a. The holding plate 13a is made of a ferromagnetic steel plate, for example, a ferritic stainless steel plate (JIS standard SUS430 or the like) or a rust-proof cold-rolled steel plate, and is formed in an annular shape by press working.

  The magnetic encoder 13b is magnetized so that the magnetic poles N and S have a predetermined pitch alternately in the circumferential direction by mixing a ferromagnetic powder made of ferrite or the like into an elastomer made of rubber or the like. In this example, the magnetic encoder 13b is made of an elastomer. However, the present invention is not limited to this. For example, the magnetic encoder 13b may be made of sintered metal obtained by hardening a ferromagnetic powder made of ferrite or the like with a metal binder.

  Here, the detection sensor 16 is mounted in a state in which it is suspended from the axle tube H via an elastic member 16a such as an O-ring. The detection sensor 16 includes a magnetic detection element such as a Hall element, a magnetoresistive element (MR element), etc. that changes its characteristics according to the flow direction of the magnetic flux, and a waveform shaping circuit that adjusts the output waveform of the magnetic detection element. The IC is mounted on the magnetic encoder 13b of the pulsar ring 13 so as to face each other through a predetermined radial clearance (air gap). Thereby, even if the radial space of the bearing portion, in particular, the sectional height of the seal 9 cannot be sufficiently secured, the magnetic flux density of the magnetic encoder 13b can be increased, and the rotational speed sensing performance can be improved.

  In the present embodiment, a sensor hole 17 into which the detection sensor 16 is inserted into the cylindrical portion 14 c of the core metal 14 is formed. The sensor hole 17 is formed at a position located at the upper part in the circumferential direction of the cylindrical portion 14c, that is, upward from a horizontal position with respect to the axial center of the cylindrical portion 14c. Thus, the sensor hole 17 is formed in the cylindrical portion 14c of the cored bar 14, and the air gap is set as small as possible by fitting the detection sensor 16 into or close to the sensor hole 17. Therefore, the sensing performance can be improved without being restricted by space.

  Further, since the seal lip 15c is provided on the inner side of the detection sensor 16, it is possible to prevent the differential oil mixed with wear powder such as iron powder from entering between the detection sensor 16 and the magnetic encoder 13b. The protection and sensing performance of the magnetic encoder 13b can be improved. In addition to non-magnetic steel plates such as austenitic stainless steel plates, for example, a core metal 14 made of a magnetic material having excellent corrosion resistance, such as ferritic stainless steel plates and rust-proof cold-rolled steel plates, is used. It is also possible to increase the degree of freedom of material selection in terms of workability and cost.

  Although not shown, the core 14 is formed of a non-magnetic steel plate such as an austenitic stainless steel plate, so that the detection sensor 16 is a cylinder in the core 14 without forming the sensor hole 17 in the cylindrical portion 14c. The radio wave signal can be transmitted through the cored bar 14 made of a non-magnetic material. As a result, dust, sand, or the like is not caught in the clearance between the magnetic encoder 13b and the detection sensor 16, and the surface of the magnetic encoder 13b can be prevented from being worn or damaged, and the sealing performance can be further improved. it can.

  The outer seal 8 is disposed so as to be in sliding contact with a metal ring 18 fitted to the inner base 6 b of the wheel mounting flange 6. As shown in an enlarged view in FIG. 3, the seal 8 is integrally joined to a core metal 19 fitted to the inner periphery of the outer end of the outer member 2 and to the core metal 19 by vulcanization adhesion or the like. It is comprised by the integral type | mold seal | sticker which consists of the sealing member 20 further. The metal core 19 is formed from an austenitic stainless steel plate or a cold-rolled steel plate that has been rust-proofed by a pressing process so as to have a substantially U-shaped cross section.

  On the other hand, the seal member 20 is made of synthetic rubber such as NBR, and is joined to the outer peripheral portion of the core metal 19 and joined to the side lip 20a and the dust lip 20b extending in a radially outward direction and the inner edge portion of the core metal 19. And has a grease lip 20c extending obliquely inward of the bearing. These side lip 20a, dust lip 20b and grease lip 20c are in sliding contact with a metal ring 18 fitted to the base 6b on the inner side of the wheel mounting flange 6. A seal member 20 is wrapped around and joined to the outer portion of the core metal 19 to prevent foreign matter such as muddy water from entering the bearing from the fitting portion between the outer member 2 and the core metal 19. Yes.

  The metal ring 18 is formed by press working from a corrosion-resistant steel plate, such as an austenitic stainless steel plate or a cold-rolled steel plate that has been rust-proofed, and is a cylindrical shape that is externally fitted to the shoulder 4e of the hub wheel 4. A fitting portion 18a, a curved portion 18b formed in an arc shape corresponding to the base portion 6b formed in an arc shape, and extending radially outward from the curved portion 18b, on the inner side of the wheel mounting flange 6 A disc portion 18c that is in close contact with the side surface 6c, and a bent portion 18d that is spaced apart from the outer diameter portion of the disc portion 18c with respect to the wheel mounting flange 6 and that extends obliquely outward in the radial direction. .

  In addition, as for this metal ring 18, the surface roughness of the steel plate used as a raw material is set to the range of Ra0.2-0.6. Thereby, a favorable seal sliding contact surface can be obtained, lip wear can be suppressed, and the sealing performance of the seal 8 can be maintained even when used in a poor environment. Note that Ra is one of JIS roughness shape parameters (JIS B0601-1994), and is an arithmetic average roughness, which means an average value of absolute value deviations from an average line.

  The base portion 6 b is formed in an arc surface having a predetermined radius of curvature r at a corner portion between the shoulder portion 4 e of the hub wheel 4 and the wheel mounting flange 6. Corresponding to this arc surface, the curved portion 18b of the metal ring 18 is formed of an arc surface having a predetermined curvature radius R, and the respective curvature radii R and r are set such that R ≧ r. Thereby, when the metal ring 18 is fitted to the base portion 6b, the curved portion 18b of the metal ring 18 is prevented from interfering with the arc surface of the base portion 6b and rising. Therefore, a gap is prevented from being generated between the side surface 6c of the wheel mounting flange 6 and the disc portion 18c of the metal ring 18, and the both are brought into close contact with each other, and the variation in the side lip 20a and the dust lip 20b is suppressed and stable. Sealing performance can be ensured.

  Further, in the present embodiment, the slinger 21 is attached to the outer periphery of the outer end portion of the outer member 2. The slinger 21 is formed by press working from a steel plate having corrosion resistance, such as an austenitic stainless steel plate or a cold-rolled steel plate that has been rust-proofed, and as shown in FIG. 7, an outer member (not shown). ), A cylindrical fitting portion 22 press-fitted into the outer periphery of the end portion, an annular groove portion 23 extending radially outward from the fitting portion 22, and a part of the annular groove portion 23, specifically, an annular groove portion. 23 and a pocket portion 24 formed at a portion closest to the road surface side. A flange portion 25 extending in the axial direction from the pocket portion 24 is integrally formed.

  As shown in FIG. 3, a flange 22a bent outward in the radial direction is formed at the end of the fitting portion 22 to increase the rigidity of the slinger 21 and to the outer member 2 of the slinger 21. The press fit is improved. The annular groove portion 23 includes a standing plate portion 23a, a cylindrical bottom portion 23b extending in the axial direction from the standing plate portion 23a, and an edge portion 23c that is bent radially inward from the bottom portion 23b. . The inner diameter D1 of the edge portion 23c is set to be slightly larger (D1> D2) than the outer diameter D2 of the bent portion 18d of the metal ring 18, and a labyrinth seal 36 is formed. Thereby, even if the grease or oil leaked from the seal 8 is scattered by the centrifugal force accompanying the rotation of the metal ring 18, it can be collected by the annular groove portion 23 and discharged to the road surface side (lower side in FIG. 1).

  Here, as shown in FIG. 6, a pocket portion 24 is formed in the lowermost portion of the slinger 21 on the road surface side by expanding a part of the fitting portion 22. And the grease or oil which flowed out from the annular groove part 23 can be collect | recovered by this pocket part 24, and can be discharged | emitted outside via the collar part 25 extended from this pocket part 24 to an inner side. The flange portion 25 is disposed in a portion of the outer member 2 away from the vehicle body mounting flange 2b, and the distal end portion 25a of the flange portion 25 is set to open to the inner side of the vehicle body mounting flange 2b. . As a result, even if the discharged grease or oil is scattered by centrifugal force, it does not adhere to the brake parts, and it is possible to reliably prevent the brake performance from being affected.

  As shown in FIG. 4, the labyrinth effect can be enhanced by setting the inner diameter D1 of the edge 23d of the slinger 26 to be smaller than the outer diameter D2 of the bent portion 18d of the metal ring 18 (D3 <D2). . That is, the annular groove 23 ′ of the slinger 26 is inclined in the radial direction in advance, and the inner diameter D 3 of the edge 23 d is larger than the outer diameter D 2 of the bent portion 18 d of the metal ring 18 (D 1> D 2). (Shown by a two-dot chain line in the figure) and press-fitted into the outer member 2, the diameter of the annular groove 23 ′ is reduced after the assembly of the bearing, and a metal ring fitted in advance to the base 6 b on the inner side of the wheel mounting flange 6. 18 can also be engaged.

  Further, the shape of the annular groove portion 23 of the slinger 21 is not limited to a rectangular cross section, and as shown in FIG. 5A, the cross section of the slinger 27 extending radially outward from the cylindrical fitting portion 22 is a circle. An arcuate annular groove 28 may be provided, or, as shown in FIG. 5B, the slinger 29 includes an annular groove 30 having a triangular cross section extending radially outward from the cylindrical fitting portion 22. May be. Moreover, as shown in (c), even if the slinger 41 is provided with the annular groove part 42 which the cross section made from a synthetic resin joined to the edge part of the cylindrical fitting part 22 by vulcanization adhesion makes a rectangular shape. good.

  In addition, although the 3rd generation structure by the side of a driving wheel was illustrated as a wheel bearing apparatus here, the wheel bearing apparatus which concerns on this invention is not restricted to this, If it is an applicable structure, 2nd generation and 2nd .5 generation or fourth generation may be used. Furthermore, in the present embodiment, an example of a double-row angular contact ball bearing using balls as the rolling elements 3 is illustrated, but it is not limited to this, and a double-row tapered roller bearing using tapered rollers as the rolling elements is used. It may be configured.

  Next, a modification of the outer seal device is shown in FIG. This sealing device basically differs from the above-described sealing device only in the slinger, and the same parts are designated by the same reference numerals, and the detailed description is omitted.

  This slinger 31 is formed by press working from an austenitic stainless steel plate or a cold-rolled steel plate that has been rust-proofed, and a cylindrical fitting portion 22 that is press-fitted into the outer periphery of the end portion of the outer member 2. The annular groove portion 32 extends radially outward from the fitting portion 22 and a pocket portion (not shown) formed in a portion of the annular groove portion 32 on the road surface side.

  The annular groove 32 includes a vertical plate portion 23a, a cylindrical bottom portion 23b extending in the axial direction from the vertical plate portion 23a, and an edge portion integrally joined to the bottom portion 23b by vulcanization and made of synthetic rubber such as NBR. 32a. The inner diameter D3 of the edge portion 32a is set to be slightly smaller than the outer diameter D2 of the bent portion 18d of the metal ring 18 (D3 <D2). Thereby, even if the grease or oil leaked from the seal 8 is scattered by the centrifugal force accompanying the rotation of the metal ring 18, it can be collected by the annular groove portion 32 and discharged to the road surface side. Further, since the edge portion 32a is formed of synthetic rubber, even if the inner diameter is set smaller than the outer diameter of the bent portion 18d of the metal ring 18, the edge portion 32a is elastically deformed and folded during assembly. Since the curved portion 18d can be overcome, there is no hindrance to the assembling work.

  FIG. 9 shows a modification of the above-described sealing device (FIG. 8). This sealing device basically differs from the above-described sealing device only in the configuration of a part of the slinger and the metal ring, and the same parts are attached to the same parts or parts having the same functions. Detailed description is omitted.

  The slinger 33 is formed by press working from an austenitic stainless steel plate or a cold-rolled steel plate that has been rust-proofed, and a cylindrical fitting portion 22 that is press-fitted into the outer periphery of the end portion of the outer member 2; An annular groove 34 extending radially outward from the fitting portion 22 and a pocket portion (not shown) formed in a part of the annular groove 34 on the road surface side.

  The annular groove 34 includes a standing plate portion 23a, a cylindrical bottom portion 23b extending in the axial direction from the standing plate portion 23a, and an edge portion that is integrally joined to the bottom portion 23b by vulcanization and made of synthetic rubber such as NBR. 34a. The edge 34a has a substantially L-shaped cross section.

  The metal ring 35 is formed by press working from an austenitic stainless steel plate or a cold-rolled steel plate that has been rust-proofed, and a cylindrical fitting portion 18a that is externally fitted to the shoulder portion 4e of the hub wheel 4, A curved portion 18b formed in an arc shape corresponding to the base portion 6b formed in an arc shape, and a circle extending radially outward from the curved portion 18b and closely contacting the inner side surface 6c of the wheel mounting flange 6 A plate portion 18c, a cylindrical portion 35a spaced from the outer diameter portion of the disk portion 18c with respect to the wheel mounting flange 6, and a bent portion 35b extending radially outward from the cylindrical portion 35a are provided.

  The inner diameter D3 of the edge 34a of the slinger 33 is set to be slightly smaller than the outer diameter D2 of the bent portion 35b of the metal ring 35 (D3 <D2), and the labyrinth seal 36 having a substantially L-shaped cross section is provided. Forming. Thereby, even if the grease or oil leaked from the seal 8 is scattered due to the centrifugal force accompanying the rotation of the metal ring 35, it can be collected by the annular groove 34 and discharged to the road surface side. Further, since the edge portion 34a is made of synthetic rubber, even when the inner diameter is set smaller than the outer diameter of the bent portion 35b of the metal ring 35, the edge portion 34a is elastically deformed and folded during assembly. The curved portion 35b can be overcome and the strong labyrinth seal 36 can prevent muddy water or the like from entering the vicinity of the seal 8 from the outside.

  FIG. 10 shows another modification of the sealing device (FIG. 3) described above. This sealing device basically differs from the above-described sealing device only in the presence or absence of a metal ring, and other detailed description is omitted by attaching the same reference numerals to the same parts or parts having the same function. To do.

  In this embodiment, the base 6b on the inner side of the wheel mounting flange 6 is not fitted with a metal ring as described above, and each lip of the seal 8 is in direct sliding contact with the base 6b. Then, a side wall 37 rising radially outward from the base portion 6b formed in an arc shape is formed, opposed to the outer side end surface 2d of the outer member 2 via a slight axial clearance, and a labyrinth seal 38 is formed. Is formed. The inner diameter D1 of the edge 23c of the slinger 21 is set to be slightly larger than the outer diameter D4 of the side wall 37 (D1> D4), thereby forming a labyrinth seal 36. Thereby, even if the grease or oil leaked from the seal 8 is scattered by the centrifugal force accompanying the rotation of the hub wheel 4, it can be collected by the annular groove portion 23 and discharged to the road surface side.

  FIG. 11 shows a modification of the above-described sealing device (FIG. 10). This sealing device basically differs from the above-described sealing device only in the shape of the side wall, and other parts of the same parts or parts having the same functions are denoted by the same reference numerals and detailed description thereof is omitted. .

  A side wall 39 is formed to rise from the base portion 6b formed in an arc shape to incline radially outward. On the other hand, a labyrinth seal 38 'is formed to face the outer end surface 2d' of the outer member 2 'via a slight axial clearance. Further, the inner diameter D1 of the edge 23c of the slinger 21 is set to be slightly larger (D1> D4) than the outer diameter D4 of the side wall 39, thereby forming the labyrinth seal 40. As a result, even if grease or oil leaked from the seal is scattered by centrifugal force, it can be collected by the annular groove 23 and discharged to the road surface side, and muddy water or the like can enter the vicinity of the seal 8 from the outside. This can be further prevented and the sealing performance of the seal 8 can be improved.

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

  The wheel bearing device according to the present invention can be applied to a wheel bearing device on the driving wheel side in which wheel bearings are mounted in openings of the drive shaft and the axle tube regardless of the structure of the bearing portion.

DESCRIPTION OF SYMBOLS 1 Inner member 2, 2 'Outer member 2a Outer rolling surface 2b Car body mounting flange 2c End side 2d of an outer member 2d' Outer end surface 3 of outer member 3 Rolling element 4 Hub wheel 4a, 5a Inner rolling surface 4b Small diameter step portion 4c Serration 4d Clamping portion 4e Shoulder portion 5 Inner ring 6 Wheel mounting flange 6a Hub bolt 6b Base portion 6c Inner side surface 7 Cage 8 Outer side seal 9 Inner side seal 10 Caps 10a, 14 , 19 Core metal 10b Elastic member 11 Retaining ring 12 Seal plate 13 Pulsar ring 13a Holding plate 13b Magnetic encoder 14a Fitting portion 14b Hook portion 14c, 23b, 35a Cylindrical portion 14d Inner diameter portion 15, 20 Seal members 15a, 15b Radial lip 15c, 20a Side lip 15d Elastic lip 16 Detection sensor 16a Elastic member 17 Sensor hole 18, 3 Metal ring 18a, 22 Fitting part 18b Curved part 18c Disk part 18d, 35b Bent part 20b Dustrip 20c Grease lip 21, 26, 27, 29, 31, 33, 41 Slinger 22a collar part 23, 23 ', 28 , 30, 32, 34, 42 Annular groove portion 23a Standing plate portions 23c, 23d, 32a, 34a Edge portion 24 Pocket portion 25 heel portion 25a Tip portion 36, 38, 38 ', 40 Labyrinth seal 37, 39 Side wall 50 Wheel mounting flange 50a Base 51 Metal ring 51a Fitting part 51b Curved part 51c Disk part 51d Umbrella part 51e Bent part 52 Seal 53 Outer member 54 Core metal 55 Seal member 55a, 55b Side lip 55c Grease lip 56 Hub ring 56a Shoulder portion 57 Drain hole 58 Slinger 58a Cylindrical portion 58b Standing plate portions D1, D3 Inner diameter D2 of the edge portion of the slinger The outer diameter D4 of the bent portion of the metal ring The outer diameter D / S of the side wall Drive shaft H Axle tube r The radius of curvature of the base R The radius of curvature of the bent portion of the metal ring

Claims (10)

An outer member integrally including a vehicle body mounting flange on the outer periphery, and a double row outer rolling surface formed integrally on the inner periphery;
A wheel mounting flange for integrally mounting a wheel at one end, an inner rolling surface facing one of the outer rolling surfaces of the double row on the outer periphery, and a small diameter step extending in the axial direction from the inner rolling surface A hub ring having a portion formed therein, and an inner ring that is press-fitted into a small-diameter step portion of the hub ring through a predetermined shimiro and has an inner rolling surface facing the other of the double-row outer rolling surfaces on the outer periphery. An inner member comprising:
A double row rolling element housed between the rolling surfaces of the inner member and the outer member so as to be freely rollable via a cage;
A seal attached to an opening of an annular space formed between the outer member and the inner member;
Outer seal among these seals is a core metal fitted to the inner periphery of the end of the outer member, a side lip that is integrally joined to the core metal and extends obliquely outward in the radial direction, and a bearing In the wheel bearing device constituted by an integral seal composed of a seal member having a grease lip extending inclinedly inwardly,
A slinger is attached to the outer periphery of the outer side end of the outer member, and this slinger is formed by press working from a corrosion-resistant steel plate and is press-fitted into the outer periphery of the end of the outer member. Portion, an annular groove portion extending radially outward from the fitting portion, and a pocket portion formed by expanding a part of the fitting portion at a portion closest to the road surface of the annular groove portion. In addition, a flange portion extending in the axial direction along the outer peripheral surface of the outer member from the pocket portion and having an open portion on the side facing the outer peripheral surface of the outer member is integrally formed. Is disposed in a portion of the outer member away from the vehicle body mounting flange, and the tip of the flange is set so as to open to the inner side of the vehicle body mounting flange. apparatus.   A base portion on the inner side of the wheel mounting flange is formed in an arc shape, and a metal ring formed by pressing from a steel plate is fitted to the base portion, and the metal ring is attached to a shoulder portion of the hub wheel. A cylindrical fitting portion to be fitted, a curved portion formed in an arc shape corresponding to the shape of the base portion, and extending radially outward from the curved portion, on the inner side surface of the wheel mounting flange The wheel bearing device according to claim 1, further comprising: a disk portion that is in close contact, wherein at least a side lip of the seal member is in sliding contact with the metal ring.   The base is formed on an arc surface having a predetermined radius of curvature r, and the curved portion of the metal ring is formed on an arc surface having a predetermined radius of curvature R corresponding to the arc surface. , R is set such that R ≧ r, the wheel bearing device according to claim 2.   The wheel bearing device according to claim 2 or 3, wherein the metal ring is formed of a steel plate having corrosion resistance, and a surface roughness of the steel plate as a raw material is set in a range of Ra 0.2 to 0.6.   The said metal ring is spaced apart with respect to the said wheel mounting flange from the outer-diameter part of the said disc part, and is equipped with the bending part extended inclining to radial direction outward. Wheel bearing device.   An annular groove portion of the slinger is a standing plate portion extending in a radial direction from the fitting portion, a cylindrical bottom portion extending in an axial direction from the standing plate portion, and an edge formed by bending inward in the radial direction from the bottom portion And a labyrinth seal is formed so that the inner diameter of the edge is set to be slightly larger than the outer diameter of the disk portion of the metal ring. Bearing device.   The wheel bearing device according to claim 1 or 6, wherein a flange that is bent radially outward is formed at an end of the fitting portion of the slinger.   The wheel bearing device according to claim 6 or 7, wherein an edge of the annular groove is formed of a synthetic rubber integrally joined to the slinger by vulcanization adhesion.   A side wall rising radially outward from the base on the inner side of the wheel mounting flange is formed, facing the outer side end surface of the outer member via a slight axial clearance, a labyrinth seal is formed, The wheel bearing device according to claim 1, wherein an inner diameter of an edge of the slinger is set to be slightly larger than an outer diameter of the side wall, and a labyrinth seal is formed.   The outer member is fixed to an axle tube supported on the lower surface of the vehicle body, and a serration is formed on the inner periphery of the hub wheel, and a hollow drive shaft is connected to transmit torque through the serration, The wheel bearing device according to claim 1, wherein a cap is press-fitted into an opening at an outer side end of the hub wheel.

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