JP2015227674A - Bearing device for wheel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bearing device for a wheel which prevents the separation of a seal at the assembling of the seal, prevents a failure of pressure-insertion by suppressing an inclination of the seal, and is improved in reliability.SOLUTION: A bearing device for a wheel comprises: a seal pressure-insertion part 23 in which a seal 9 is pressure-inserted into a deep position at an outer side rather than an end face 10c at an inner side at an internal periphery of an end face of an outer member 10; and a pressure-insertion guide part 24 which is formed larger in diameter than the seal pressure-insertion part 23 at the inner side via a step 23a from the seal pressure-insertion part 23. A tip of a fitting part 19a of a core grid 19 is formed thin in thickness, a seal member 20 is joined to the tip so as to cover the tip while wrapping around the tip, a nose part 21 larger in diameter than an outside diameter of the fitting part 19a is formed at an external peripheral face of the seal member, an interference d between the nose part 21 and the pressure-insertion part 24 is set at 0.1 to 0.2 mm in diameter, and a radial clearance S between the fitting part 19a of the core grid 19 and the pressure-insertion part 24 is set at 0 to 0.3 mm in diameter.

Description

  The present invention relates to a wheel bearing device for rotatably supporting a wheel of an automobile or the like with respect to a suspension device. More specifically, the present invention prevents seal separation during assembly of a seal and suppresses the tilt of the seal to cause poor press-fitting. The present invention relates to a wheel bearing device that prevents the above and improves the reliability.

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

  These bearing portions are fitted with seals to prevent leakage of grease sealed inside the bearings and to prevent intrusion of rainwater, dust and the like from the outside. Various types of seals with improved sealing performance have been proposed, but in a wheel bearing device used in a poor environment, as a typical seal having muddy water resistance, annular seal plates arranged opposite to each other A so-called pack seal is known which is a composite seal composed of a slinger and a slinger.

  On the other hand, in recent years, the torque of the bearing portion has been reduced for improving the fuel efficiency of automobiles. Of the rotational torque of the bearing portion, the rotational torque of the seal is dominant. That is, the sliding resistance of the seal is larger than the rolling resistance, and the ratio of the sliding resistance of the seal to the rotational torque is high. Further reduction in torque is required for the seal of the wheel bearing device.

  In the conventional pack seal, the seal plate and the slinger are not separated by the tension force of the grease lip. However, since the grease lip is affected by the reaction force of the side lip and is established by the relationship between the reaction force of the side lip and the tension force of the grease lip, it is inevitably more than the one that blocks the leakage of grease, which is the original function. Thickness and squeeze increase. On the other hand, with the demand for lower torque, the grease lip must be reduced in size, so that while ensuring sealing performance, the sliding resistance of the seal is reduced to lower torque, and the seal itself and A method for assembling a wheel bearing seal as shown in FIG. 7 is known as a method for preventing separation of the seal before assembly.

  As shown in (a), the seal 50 is formed of a pack seal made up of an annular seal plate 51 and a slinger 52 arranged to face each other. The seal plate 51 includes a cored bar 54 attached to the outer member 53 and a seal member 55 integrally joined to the cored bar 54 by vulcanization adhesion. The seal member 55 is made of synthetic rubber, and has first and second side lips 55a and 55b that are inclined and extended radially outward, and a grease lip 55c that is inclined and extended inward of the bearing. .

  The pressing jig 56 includes a pressing member 58 that is fitted into the jig main body 57 via an elastic member 57a so as to be freely advanced and retracted. A concave portion 58 a having a step T 0 corresponding to the step between the end surface 53 a of the outer member 53 and the end surface of the seal plate 51 is formed on the front end surface of the pressing member 58. The jig main body 57 includes a flat pressing surface 57b that abuts against the side surface of the standing plate portion 52b of the slinger 52.

  As shown in (b), the slinger 52 is held on the holding surface 59a of the holding jig 59, and the pressing member 58 is brought into contact with the end surface of the seal plate 51 with a predetermined pressing force (white arrow A). By sliding the pressing jig 56 (white arrow B), only the seal plate 51 is slid with respect to the slinger 52, and the first and second side lips 55a and 55b are moved from the side surface of the standing plate portion 52b of the slinger 52. The air pressure between the lip sliding contact portions is released after being temporarily separated. Thereafter, the end surface of the seal plate 51 and the side surface of the standing plate portion 52b of the slinger 52 are held in a substantially flush state (regular state), and the pressing jig 56 is connected to the inner periphery of the inner member of the outer member 53 and the inner ring. It is pressed in the direction of the opening of the annular space formed by the outer diameter of 60 (indicated by a black arrow in the figure).

  And as shown in (c), the recessed part 58a of the press member 58 abuts on the end surface 53a of the outer member 53. Thereafter, the jig body 57 is slid (white arrow B), the pressing surface 57b abuts the end surface 53a of the outer member 53, and the pressing member 58 receives a reaction force (white arrow A), and at the same time, the slinger 52 The pressing surface 57b is brought into contact with the side surface of the upright plate portion 52b, and the assembly is completed with the end surface of the seal plate 51 and the side surface of the upright plate portion 52b of the slinger 52 held substantially flush.

  As described above, the pressing jig 56 includes the pressing member 58 that is inserted into the jig main body 57 through the elastic member 57a so as to be able to advance and retreat. The pressing member 58 allows the seal plate 51 to be moved by the spring force of the elastic member 57a. The spring force is set to be smaller than the pressure input when the seal plate 51 is fitted to the inner periphery of the end of the outer member 53. Thereby, the pressure difference between the air pressure between the lip sliding contact portion and the outside air can be easily released, and the seal plate 51 and the slinger 52 are not separated and are incorporated in the wheel bearing while maintaining the positional relationship. (For example, refer to Patent Document 1).

JP 2012-159170 A

  However, in the case of the wheel bearing device as shown in FIG. 8, there are some problems at the stage of assembling the seal. This wheel bearing device integrally has a vehicle body mounting flange 61b to be attached to a suspension device (not shown) on the outer periphery, double row outer rolling surfaces 61a, 61a are formed on the inner periphery, and the fixed side. The outer member 61 as a member, the inner rolling surfaces 62a and 63a facing the double row outer rolling surfaces 61a and 61a are formed on the outer periphery, respectively, and the inner member 64 as a rotation side member and both rolling It is formed between the outer members 61 and the inner members 64 and the double rows of balls 66 and 66 accommodated so as to roll between the surfaces 61a and 62a and 61a and 63a via the retainers 65 and 65. And seals 67 and 68 attached to the opening of the annular space. 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. 8), and the side closer to the center is referred to as the inner side (right side in FIG. 8).

  The inner member 64 integrally has a wheel mounting flange 69 for mounting a wheel (not shown) at one end, an inner rolling surface 62a on the outer periphery, and a small diameter extending in the axial direction from the inner rolling surface 62a. The hub wheel 62 includes a stepped portion 62b, and the inner ring 63 is press-fitted into the small-diameter stepped portion 62b of the hub wheel 62 and has an inner rolling surface 63a formed on the outer periphery. An annular encoder 70 in which characteristics in the circumferential direction are alternately changed at equal intervals is fixed to the outer diameter of the inner ring 63.

  As shown in an enlarged view in FIG. 9, the inner-side seal 68 is constituted by a pack seal made up of an annular seal plate 71 and a slinger 72 arranged to face each other. The seal plate 71 includes a core metal 73 attached to the outer member 61 and a seal member 74 integrally joined to the core metal 73 by vulcanization adhesion. The metal core 73 is formed into a substantially L-shaped cross section by pressing from a steel plate, and a cylindrical fitting portion 73a that is press-fitted into the inner periphery of the outer side end of the outer member 61 through a predetermined shimiro, And an inner diameter portion 73b extending radially inward from the end of the fitting portion 73a. And the sealing member 74 turns around and the nose part 75 is formed so that the outer surface which extends over the fitting part 73a from the internal diameter part 73b may be covered.

  The seal member 74 is made of synthetic rubber, and includes a side lip 74a that extends obliquely outward in the radial direction, and a dust lip 74b and a grease lip 74c that extend in a bifurcated manner on the inner diameter side of the side lip 74a. ing.

  On the other hand, the slinger 72 is formed into a substantially L-shaped section by pressing from a steel plate, and a cylindrical portion 72a that is press-fitted into the outer peripheral surface 63a of the inner ring 63, and a vertical plate portion that extends radially outward from the cylindrical portion 72a. 72b. The outer edge of the standing plate portion 72b of the slinger 72 is opposed to the seal member 71 through a slight radial clearance to form a labyrinth seal 76.

  The side lip 74a of the seal member 74 is slidably contacted with the side surface of the standing plate portion 72b of the slinger 72 via an axial squeeze, and the dust lip 74b is slidably contacted with the cylindrical portion 72a of the slinger 72 via a radial shimeros. The grease lip 74c is opposed to the cylindrical portion 72a via a radial clearance to form a labyrinth seal.

  Generally, when the inner seal 68 is press-fitted, the seal 68 is press-fitted with the wheel mounting flange 69 on the outer side of the apparatus facing down and the inner side facing up, 10), as shown in FIG. 10, in the structure in which the seal press-fit portion 77 is deeper on the inner side of the bearing than the end surface 61c on the inner side of the outer member 61, specifically, in the outer member 61, In the structure where the width a of the seal insertion portion is larger than the seal width W0 (W0 <a), there are the following problems.

  That is, as shown in FIG. 11A, the seal 68 is press-fitted into the inner ring 63 via the annular guide jig 78, but the outer diameter of the inner ring 63 is not stepped and the outer peripheral surface 63a is formed straight. When the inner ring 63 and the slinger 72 are press-fitted before the outer member 61 and the seal plate 71, as shown in FIG. 12B, the dust strip 74b is shown in FIG. As shown, there is a possibility that the seal plate 71 and the slinger 72 are separated and separated by the weight of the seal plate 71. In recent years, if the reaction force between the dust lip 74b and the grease lip 74c is set small due to a demand for lower torque, the possibility increases.

  In this case, this problem is solved by providing a step on the outer peripheral surface 63a of the inner ring 63, and the guide jig 78 guides and press-fits to the front side of the seal press-fitting portion 77 of the outer member 61, but FIG. For example, even if the step 63b is provided on the outer peripheral surface 63a of the inner ring 63 ′, if the step 77a with the seal press-fitting portion 77 ′ of the outer member 61 ′ is not sufficient, the guide jig 78 itself is sealed. Since it cannot be inserted in front of the press-fit portion 77 ′, the seal 68 is dropped to the seal press-fit portion 77 ′. At that time, the seal 68 may be tilted or the core may be displaced, and a press-fit failure may occur. Due to such a press-fitting failure, the core metal 73 and the slinger 72 are scratched, and the seal 68 having a half metal structure in which the seal member 74 wraps around and joins the end of the core metal 73 is formed to wrap around. Further, the nose portion 75 may be broken, and the airtightness of the fitting portion of the seal 68 may be impaired. Although it is conceivable to sufficiently increase the step 77a between the outer member 61 'and the seal press-fitting portion 77', the outer member 61 'becomes thin and the strength cannot be secured.

  The present invention has been made in view of such circumstances, and in a structure in which the seal press-fit portion is located deeper on the bearing inner side than the inner side end face of the outer member, the seal is separated at the time of assembling the seal. An object of the present invention is to provide a wheel bearing device that prevents the occurrence of press-fitting failure by suppressing the inclination of the seal and improves the reliability.

  In order to achieve the object, the invention according to claim 1 of the present invention includes an outer member in which a double row outer rolling surface is integrally formed on the inner periphery, and an outer rolling surface of the double row on the outer periphery. An inner member in which a double-row inner rolling surface facing the inner member is formed, and a double-row rolling element accommodated so as to roll between the inner member and the outer member. A seal that seals both ends of the opening portion of the annular space formed between the inner member and the outer member, and the inner seal includes an annular seal plate and a slinger arranged opposite to each other. The core plate is press-fitted into the inner periphery of the end portion of the outer member, and the side that is joined to the core bar and extends at an incline in the radial direction at least. A sealing member integrally having a lip, and the slinger has an L-shaped cross section. A cylindrical portion that is press-fitted into the outer periphery of the end portion of the inner member, and a standing plate portion that extends radially outward from the cylindrical portion, and the side lip is fixed to the standing plate portion in a predetermined axial direction. In the wheel bearing device slidably contacted with each other, a seal press-fitting portion into which the seal is press-fitted to an inner periphery of an end portion of the outer member, and a seal press-fitting portion and an inner side end surface of the outer member. In the meantime, a press-fitting guide portion having a larger diameter than the seal press-fitting portion is provided at a position facing the outer diameter surface of the inner member.

  In this way, an outer member in which a double-row outer rolling surface is integrally formed on the inner periphery, and an inner member in which a double-row inner rolling surface facing the outer surface of the double row is formed on the outer periphery. An annular space formed between the inner member and the outer member, a member, a double row of rolling elements housed between the inner member and the outer member in a freely rolling manner A seal that seals both ends of the opening, wherein the inner seal is composed of a composite seal composed of an annular seal plate and a slinger arranged opposite to each other, and the seal plate of the outer member A sling is formed in an L-shaped cross section, and includes a metal core that is press-fitted into the inner periphery of the end portion, and a seal member that is joined to the metal core and has a side lip that is at least radially inclined and extends. A cylindrical portion that is press-fitted into the outer periphery of the end portion of the inner member, and radially outward from the cylindrical portion. In the wheel bearing device in which the side lip is slidably contacted to the standing plate portion via a predetermined axial direction shim, the seal is press-fitted into the inner periphery of the end portion of the outer member. A seal press-fit portion, and a press-fit guide portion formed between the seal press-fit portion and the inner side end surface of the outer member at a position facing the outer diameter surface of the inner member and having a larger diameter than the seal press-fit portion. The seal can be smoothly and stably pressed into the seal press-fitting part of the outer member, preventing separation of the seal during assembly, and suppressing the tilt of the seal to prevent poor press-fitting. It is possible to provide a wheel bearing device that is prevented and improved in reliability.

  Preferably, as in the invention described in claim 2, the distal end portion of the fitting portion of the metal core is formed to be thin, and the seal member wraps around and is joined so as to cover the distal end portion, and the outer peripheral surface thereof A nose portion having a diameter larger than the outer diameter of the fitting portion of the cored bar is formed, and a radial clearance is provided between the fitting portion of the cored bar and the press-fitting guide portion. If the press-fitting guide part has a shimiro, the seal can be prevented from being separated during assembly.

  Further, as in the invention described in claim 3, if the squeeze between the nose part and the press-fitting guide part is set to 0 to 0.2 mm in diameter, deterioration due to dragging of the nose part during press-fitting is prevented. be able to.

  Further, as in the invention described in claim 4, if the radial clearance between the fitting portion of the cored bar and the press-fitting guide portion is set to 0 to 0.3 mm in diameter, the pressure input is increased. In addition, it is possible to suppress the tilting of the seal plate, and it is possible to prevent poor press-fitting.

  Further, as in the invention described in claim 5, the distal end portion of the fitting portion of the cored bar is formed to be thin, and the seal member wraps around and is joined so as to cover the distal end portion. A nose portion having a diameter larger than the outer diameter of the fitting portion of the cored bar is formed, and the squeeze between the nose portion and the press-fitting guide portion is set to -0.1 to 0.2 mm in diameter, and If the clearance in the radial direction between the fitting portion of the metal core and the press-fitting guide portion is set to 0 to 0.3 mm in diameter, the seal plate can be prevented from tilting without increasing the pressure input. The tolerance range of the inner diameter of the press-fit guide portion can be relaxed, and the cost can be reduced.

  Further, as in the invention described in claim 6, if the crossing range of the inner diameter dimension of the press-fit guide portion is set within ± 0.08 mm, the processing time can be shortened together with the management cost of the press-fit guide portion. Manufacturing cost can be reduced.

  Further, as in the invention described in claim 7, if a step formed of a tapered surface with an inclination angle of 10 to 45 ° that gradually increases in diameter toward the inner side is formed between the seal press-fitting portion and the press-fitting guide portion. , It is possible to regulate the misalignment of the seal during press-fitting.

  Further, as in the invention described in claim 8, if the press-fitting guide portion is formed on a tapered surface having an inclination angle of 0 to 5 ° gradually expanding toward the inner side, separation of the seal during assembly is prevented. In addition, the inclination of the seal can be suppressed to prevent press-fitting failure, and the reliability can be improved.

  The wheel bearing device according to the present invention includes an outer member in which a double row outer rolling surface is integrally formed on an inner periphery, and a double row inner rolling that faces the outer rolling surface of the double row on an outer periphery. An inner member having a surface formed thereon, a double row rolling element housed between the rolling surfaces of the inner member and the outer member, and the inner member and the outer member. A seal that seals both ends of the opening portion of the annular space formed between the inner seal and the inner seal formed of a composite seal composed of an annular seal plate and a slinger disposed opposite to each other. The seal plate is press-fitted into the inner periphery of the end portion of the outer member, and the seal member integrally joined to the core metal and having at least a side lip extending obliquely outward in the radial direction; The slinger is formed in an L-shaped cross section, and the end of the inner member A wheel bearing having a cylindrical portion that is press-fitted into the outer periphery, and a vertical plate portion that extends radially outward from the cylindrical portion, and the side lip is slidably contacted with the vertical plate portion via a predetermined axial squeeze In the apparatus, an outer diameter of the inner member between a seal press-fitting portion into which the seal is press-fitted into an inner periphery of an end portion of the outer member, and an end surface on the inner side of the outer member. Since it is provided with a press-fitting guide part formed with a larger diameter than the seal press-fitting part at a position facing the surface, the seal can be pressed into the seal press-fitting part of the outer member smoothly and stably, It is possible to provide a wheel bearing device that prevents separation of the seal at the time of assembly and prevents the press-fitting failure by suppressing the inclination of the seal and improves the reliability.

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 the seal | sticker of the inner side of FIG. It is a principal part enlarged view which shows the seal part of the inner side of FIG. (A) is explanatory drawing which shows the state which press-fits the seal | sticker of FIG. 3, (b) is the elements on larger scale of the A section of (a). It is the elements on larger scale of the B section of Fig.4 (a). It is a principal part enlarged view which shows the modification of Fig.4 (a). (A)-(c) is explanatory drawing which shows the assembly method of the conventional bearing seal for wheels. It is a longitudinal cross-sectional view which shows the conventional wheel bearing apparatus. It is a principal part enlarged view which shows the inner side seal | sticker of FIG. It is a principal part enlarged view which shows the seal part of the inner side of FIG. (A) is explanatory drawing which shows the state which press-fits the seal | sticker of FIG. 10, (b) is the elements on larger scale of (a). (A) is explanatory drawing which shows a malfunction in the state which press-fits the seal | sticker of Fig.11 (a), (b) is explanatory drawing which shows another malfunction.

  An outer member integrally having a vehicle body mounting flange to be attached to the vehicle body on the outer periphery, a double row outer rolling surface formed integrally on the inner periphery, and a wheel mounting flange for mounting a wheel on one end A hub wheel integrally formed 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 the hub wheel An inner member formed of an inner ring that is press-fitted into a small-diameter step portion and has an inner rolling surface that is opposed to the other outer rolling surface of the double row on the outer periphery, and each of the inner member and the outer member. The opening of the annular space formed between the rolling elements of a double row accommodated between the rolling surfaces and the inner member and the inner side end of the outer member is sealed. A seal, and an annular seal plate and a slinger disposed opposite to each other. The seal plate is integrally joined to the core metal by vulcanization adhesion, and at least radially outward. A sealing member integrally having an inclined side lip extending in an inclined manner, a cylindrical portion in which the slinger is formed in an L-shaped cross section and is press-fitted into the outer periphery of the end of the inner member, and a diameter from the cylindrical portion In the wheel bearing device in which the side lip is slidably contacted to the standing plate portion via a predetermined axial direction shimshiro, the inner end portion of the outer member A seal press-fitting portion into which the seal is press-fitted deeper on the outer side than the inner side end face of the outer member, and a larger diameter than the seal press-fitting portion on the inner side through a step from the seal press-fitting portion. It is equipped with a press-fitting guide part. The tip of the fitting part of the metal core is formed thin, and the seal member is wrapped around and joined to cover the tip part, and the outer diameter thereof is larger than the outer diameter of the fitting part of the metal core The nose portion is formed, the squeeze between the nose portion and the press-fit guide portion is set to a diameter of −0.1 to 0.2 mm, and the fitting direction of the cored bar and the press-fit guide portion is the radial direction. The clearance is set to 0 to 0.3 mm in diameter.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
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 a seal on the inner side of FIG. 1, and FIG. 3 is an inner side view of FIG. FIG. 4A is an explanatory view showing a state in which the seal of FIG. 3 is press-fitted, FIG. 4B is a partial enlarged view of part A of FIG. 4 (a) is a partially enlarged view of a portion B, and FIG. 6 is an enlarged view of a main portion showing a modification of FIG. 4 (a).

  The wheel bearing shown in FIG. 1 is referred to as the third generation on the driven wheel side, and is a double row rolling element (rolling member housed between the inner member 1 and the outer member 10, and both the members 1, 10 so as to be freely rollable). Ball) 6 and 6. The inner member 1 includes a hub ring 2 and an inner ring 3 that is press-fitted and fixed to the hub ring 2.

  The hub wheel 2 integrally has a wheel mounting flange 4 for mounting a wheel (not shown) at an end on the outer side, and a hub bolt for fixing the wheel at a circumferentially equidistant position of the wheel mounting flange 4. 5 is planted. Further, one (outer side) inner rolling surface 2a and a cylindrical small-diameter step portion 2b extending in the axial direction from the inner rolling surface 2a are formed on the outer periphery of the hub wheel 2.

  On the other hand, the inner ring 3 is formed with the other (inner side) inner rolling surface 3a on the outer periphery, and is press-fitted into the small-diameter step portion 2b of the hub wheel 2 through a predetermined shimiro, and the end portion of the small-diameter step portion 2b has a diameter. It is fixed in the axial direction with a predetermined bearing preload applied by a caulking portion 2c formed by plastic deformation outward in the direction.

  The hub wheel 2 is formed of medium and high carbon steel containing 0.40 to 0.80% by weight of carbon such as S53C, and includes a base portion 11 on the inner side of the wheel mounting flange 4 serving as a seal land portion of the seal 8 described later, The surface hardness is set to a range of 58 to 64 HRC by induction hardening from the inner side rolling surface 2a on the outer side to the small diameter step portion 2b. As a result, not only the wear resistance of the base 11 of the wheel mounting flange 4 is improved, but also sufficient mechanical strength against the rotational bending load applied to the wheel mounting flange 4 is obtained. Strength and durability are improved. The caulking portion 2c is an unquenched portion with the surface hardness after forging. On the other hand, the inner ring 3 and the rolling element 6 are made of a high carbon chrome bearing steel such as SUJ2, and are hardened in the range of 58 to 64 HRC for the inner ring 3 and 62 to 67 HRC for the inner ring 3 to the core portion by quenching.

  The outer member 10 integrally has a vehicle body mounting flange 10b for mounting to a vehicle body (not shown) on the outer periphery, and a double row facing the inner rolling surfaces 2a, 3a of the inner member 1 on the inner periphery. The outer rolling surfaces 10a and 10a are integrally formed. The outer member 10 is formed of medium and high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, like the hub wheel 2, and at least the double row outer raceway surfaces 10 a and 10 a are formed by induction hardening. The surface hardness is set in the range of 58 to 64 HRC. And the double row rolling elements 6 and 6 are accommodated between each rolling surface 10a, 2a and 10a, 3a, and these double row rolling elements 6 and 6 are rollably hold | maintained by the holder | retainers 7 and 7. ing. Seals 8 and 9 are attached to the opening of the annular space formed between the outer member 10 and the inner member 1, and leakage of lubricating grease sealed inside the bearing and rainwater and dust from the outside. Etc. are prevented from entering the inside of the bearing.

  In addition, although the wheel bearing apparatus comprised by the double row angular contact ball bearing which used the ball for the rolling element 6 was illustrated here, it is not restricted to this, The double row tapered roller bearing which used the tapered roller for the rolling element 6 It may consist of. In addition, here, a third generation structure in which the inner raceway surface 2a is formed directly on the outer periphery of the hub wheel 2 is illustrated, but although not shown, a pair of inner rings are press-fitted and fixed to the small-diameter step portion of the hub wheel. It may be a first generation or second generation structure.

  In the present embodiment, as shown in FIG. 3, the pulsar ring 12 is press-fitted into the outer periphery of the inner ring 3. The pulsar ring 12 includes a support ring 13 formed in an annular shape, and a magnetic encoder 14 that is integrally joined to a side surface of the support ring 13 by vulcanization adhesion or the like. This magnetic encoder 14 is a rotary encoder for detecting the rotational speed of a wheel by mixing magnetic powder such as ferrite in an elastomer such as rubber and magnetizing magnetic poles N and S alternately in the circumferential direction.

  The support ring 13 is made of a ferromagnetic steel plate, for example, a ferritic stainless steel plate (JIS standard SUS430 system or the like) or a rust-proof cold rolled steel sheet (JIS standard SPCC system or the like) by press working. It has a cylindrical portion 13a that is formed in a letter shape and is press-fitted into the inner ring 3, and a standing plate portion 13b that extends radially outward from the cylindrical portion 13a. The magnetic encoder 14 is joined to the inner side surface of the upright plate portion 13b.

  As shown in FIG. 1, the outer-side seal 8 is constituted by an integrated sealing device including a cored bar 15 and a seal member 16 that is integrally vulcanized and bonded to the cored bar 15. The metal core 15 is formed from a ferritic stainless steel plate, an austenitic stainless steel plate (JIS standard SUS304 series, etc.), or a cold rolled steel plate that has been rust-proofed by press working, and has a substantially L-shaped cross section. A cylindrical fitting portion 15a that is press-fitted to the inner periphery of the outer side end of the side member 10 via a predetermined shimiro, and an inner diameter portion 15b that extends radially inward from the end of the fitting portion 15a. doing. And the sealing member 16 wraps around and joins so that the outer surface ranging from the internal diameter part 15b to the fitting part 15a may be comprised, and the so-called half metal structure is comprised. Thereby, the airtightness of the fitting part 15a can be improved and the inside of a bearing can be protected.

  On the other hand, the seal member 16 is made of a synthetic rubber such as NBR (acrylonitrile-butadiene rubber), extends in a radially outward direction, and has a predetermined axial shimiro at the base 11 of the wheel mounting flange 4 formed in an arc shape. Are integrally provided with a side lip 16a and a dust lip 16b slidably in contact with each other, and a grease lip 16c extending obliquely toward the inner side of the bearing and facing the base 11 via a minute radial clearance. As the material of the seal member 16, 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.

  Next, as shown in an enlarged view in FIG. 2, the inner-side seal 9 is composed of a pack seal comprising an annular seal plate 17 and a slinger 18 which are formed in a substantially L-shaped cross section and are arranged to face each other. Has been.

  The annular seal plate 17 includes a cored bar 19 press-fitted into the inner periphery of the inner side end of the outer member 10, and a seal member 20 integrally vulcanized and bonded to the cored bar 19. The core metal 19 is formed from a ferritic stainless steel plate, an austenitic stainless steel plate, or a cold-rolled steel plate that has been rust-proofed by pressing to have a substantially L-shaped cross section, and is formed on the inner periphery of the end of the outer member 10. It has a cylindrical fitting portion 19a that is press-fitted through a predetermined shimoshiro, and an inner diameter portion 19b that extends radially inward from the end of the fitting portion 19a. And while the front-end | tip part of the fitting part 19a of the metal core 19 is formed thinly, the sealing member 20 wraps around and joins so that this front-end | tip part may be covered, The fitting part 19a of the metal core 19 is joined to the outer peripheral surface. A nose portion (annular convex portion) 21 having a diameter slightly larger than the outer diameter is formed.

  On the other hand, the slinger 18 is formed of a ferritic stainless steel plate or a cold-rolled steel plate that has been rust-proofed by a press process so that its cross section is substantially L-shaped, and is a cylindrical portion 18a that is press-fitted into the outer peripheral surface 3b of the inner ring 3. And a standing plate portion 18b extending radially outward from the cylindrical portion 18a. The outer edge of the standing plate portion 18b of the slinger 18 is opposed to the seal member 17 through a slight radial clearance to constitute a labyrinth seal 22.

  The seal member 20 is made of a synthetic rubber such as NBR, extends from the end of the inner diameter portion 19b of the core metal 19 in an inclined manner toward the radially outer inner side, and is predetermined on the outer side surface of the standing plate portion 18b of the slinger 18. The side lip 20a is slidably contacted with each other via an axial shimiro, and a dust lip 20b and a grease lip 20c are provided on the inner diameter side of the side lip 20a. The dust lip 20b is slidably contacted with the cylindrical portion 18a of the slinger 18 via a predetermined radial squeeze, and the grease lip 20c is opposed to the cylindrical portion 18a of the slinger 18 with a predetermined radial clearance to provide a labyrinth seal. It is composed. As a material of the seal member 20, other than the exemplified NBR, for example, HNBR, EPDM, ACM, FKM, or silicon rubber can be exemplified.

  Here, as shown in FIG. 3, the seal 9 is press-fitted into the inner periphery of the inner side end of the outer member 10. In the inner periphery of the end portion of the outer member 10, the seal 9 is press-fitted into the seal press-fitting portion 23 located deeper on the outer side (bearing inward side) than the end surface 10c on the inner side. Then, a press-fit guide portion formed slightly larger in diameter than the seal press-fit portion 23 at a position facing the outer diameter surface of the inner ring 3 on the inner side (opening side) from the seal press-fit portion 23 through a predetermined step 23a. 24. Furthermore, in the present embodiment, the cover is provided with a cover press-fit portion 25 having a slightly larger diameter (radius 0.5 mm or less) than the press-fit guide portion 24 in the opening. Since the press-fit guide portion 24 has a slightly large diameter, the strength can be ensured without the outer member 10 being thin.

  4A, the width W1 of the seal press-fitting portion 23 is larger than the width W0 of the seal plate 17 of the seal 9 and is a press-fit formed at a position facing the outer diameter surface of the inner ring 3. The guide portion 24 is formed beyond the end face on the inner side of the inner ring 3, and the width W2 of the press-fit guide portion 24 is set larger than the width W0 of the seal 9 (W0 <W2). And as shown in (b), the inner diameter D of the press-fitting guide part 24 is slightly larger than the outer diameter of the fitting part 19a of the metal core 19 in the seal 9, and more than the outer diameter of the nose part 21. Is also formed with a slightly smaller diameter. In other words, the press-fitting guide portion 24 has a nose portion 21 and a predetermined squeeze d, but is set so as to have a predetermined radial (guide) clearance S with the fitting portion 19a of the cored bar 19.

  The seal 9 is pushed in a state where it is in contact with the inner side surface of the seal 9 by a press-fitting jig (not shown). However, as in this embodiment, the outer diameter of the inner ring 3 is not stepped and the outer peripheral surface 3b is straight. Even when the inner ring 3 and the slinger 18 are press-fitted before the outer member 10 and the seal plate 19, the press-fitting guide portion 24 is located at a position facing the outer diameter surface of the inner ring 3 of the outer member 10. Therefore, the nose portion 21 of the seal 9 comes into contact with the press-fitting guide portion 24, and this elastic reaction force is generated. Accordingly, it is possible to prevent the seal plate 17 and the slinger 18 from separating apart due to the weight of the seal plate 17. Further, since the seal 9 does not fall down to the seal press-fitting portion 23, there is no possibility that the seal 9 is tilted or the core is displaced and a press-fitting failure occurs.

  Further, since the radial clearance S exists between the press-fit guide portion 24 and the fitting portion 19a of the core metal 19, this press-fit guide portion 24 serves as a guide jig for the seal 9, and the conventional Thus, since the guide jig cannot be inserted to the front of the seal press-fitting part, the problem that the seal falls to the seal press-fitting part can be solved. Therefore, the seal 9 can be smoothly and stably press-fitted into the seal press-fitting portion 23 of the outer member 10, and the seal 9 can be prevented from being separated at the time of assembly, and the tilt of the seal 9 can be suppressed to prevent press-fitting. Thus, it is possible to provide a wheel bearing device with improved reliability.

  The diameter d of the press-fitting guide portion 24 and the nose portion 21 is set to 0 to 0.2 mm in diameter. When this squeezing d exceeds 0.2 mm, not only the pressure input increases, but also the airtightness may be lowered due to the deterioration of the nose portion 21 during the press-fitting, which is not preferable.

  The radial clearance S between the cored bar 19 and the fitting portion 19a is set to 0 to 0.3 mm in diameter. When the radial clearance S exceeds 0.3 mm, it is difficult to suppress the tilting of the seal plate 17, which is not preferable because a press-fitting failure is induced.

  In addition, you may set the squeeze d of the press-fit guide part 24 and the nose part 21 in the range of -0.1-0.2 mm (Simechiro d -0.1 mm means a radial clearance). In other words, the squeeze d between the press-fitting guide portion 24 and the nose portion 21 is changed from a small “clearance fit” to a small “tight fit” as “fitting tolerance” according to JIS standard (JIS B 0401 (1986)). It is only necessary to set the range, in other words, “intermediate fit” in which a minute gap is present from a minute gap.

  As described above, even if there is a clearance fit range in the fit tolerance between the press-fitting guide portion 24 and the nose portion 21, the core metal 19 and the nose portion 21 of the seal 9 are pressed into the seal press-fit portion 23 with a squeeze. If this is the case, the airtightness will not be impaired. For example, even if there is such a clearance on the lower limit side of the shimoshiro d, the radial clearance S with the fitting portion 19a of the metal core 19 is set to 0 to 0.3 mm. This is because the inclination of the seal plate 17 can be sufficiently suppressed by the restriction. As a result, the crossing range ΔD of the inner diameter dimension D of the press-fit guide portion 24 can be relaxed within ± 0.08 mm, and together with the management cost of the press-fit guide portion 24, the processing time can be shortened and the manufacturing cost can be reduced. it can.

  Here, the fitting portion 17a of the metal core 17 in the seal 9 is formed thin, and the sealing member 20 is wrapped around and joined so as to cover the tip portion, and the fitting portion of the metal core 19 is attached to the outer peripheral surface thereof. Although the configuration in which the nose portion 21 having a diameter slightly larger than the outer diameter of 19a is illustrated, the present invention is not limited to this, and although not shown, the sealing member wraps around the fitting portion of the cored bar. A seal having no nose portion may be used, and the fit between the press-fitting guide portion and the fitting portion of the core metal may be set to an intermediate fit.

  Further, as shown in FIG. 5, the step 23 a of the seal press-fit portion 23 is formed on a tapered surface having a predetermined inclination angle α so that the diameter gradually increases from the seal press-fit portion 23 to the press-fit guide portion 24. In the present embodiment, the inclination angle α is set in a range of 10 to 45 °. When the inclination angle α is less than 10 °, the effect of regulating the misalignment at the time of press-fitting becomes small. On the other hand, when the inclination angle α exceeds 45 °, the ratio of the axial component force increases due to the contact of the seal plate 17, and it is difficult to suppress the misalignment of the seal 9.

  FIG. 6 shows a modification of the outer member 10 described above. This embodiment basically differs from the above-described embodiment (FIG. 3) only in the configuration of the press-fitting guide portion 24, and other parts having the same parts or the same functions are denoted by the same reference numerals and detailed. Description is omitted.

  The outer member 25 is formed with a seal press-fit portion 23 into which the seal 9 is press-fitted at a position deeper on the outer side than the end surface 10c on the inner side, and a press-fit guide portion 26 that gradually increases in diameter from the seal press-fit portion 23 to the inner side. Is formed.

  In the present embodiment, unlike the above-described embodiment, there is no tapered step 23a at the joint between the seal press-fit portion 23 and the press-fit guide portion 24, and the entire press-fit guide portion 26 gradually moves toward the inner side (opening side). It is formed on a tapered surface having a predetermined inclination angle β that expands in diameter. Then, the squeezing between the press-fitting guide portion 26 and the nose portion 21 is in the range of −0.1 to 0.2 mm in diameter as in the above-described embodiment, and the radial clearance with the fitting portion 19a of the core metal 19 Is set to be more than 0 ° and not more than 5 ° so that is 0 to 0.3 mm. As a result, as in the above-described embodiment, separation of the seal 9 during assembly can be prevented, and the tilt of the seal 9 can be suppressed to prevent press-fitting failure and reliability 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 having a first to fourth generation structure in which a pack seal is attached to an end portion of an outer member regardless of a driving wheel side or a driven wheel side. it can.

DESCRIPTION OF SYMBOLS 1 Inner member 2 Hub wheel 2a, 3a Inner rolling surface 2b Small diameter step part 3 Inner ring 3b Inner ring outer peripheral surface 4 Wheel mounting flange 5 Hub bolt 6 Rolling body 7 Cage 8 Outer side seal 9 Inner side seals 10, 25 Outer member 10a Outer rolling surface 10b Car body mounting flange 11 Inner base 12 of wheel mounting flange Pulsar ring 13 Support ring 13a, 18a Cylindrical portion 13b, 18b Standing plate portion 14 Magnetic encoder 15, 19 Core metal 15a, 19a Fitting Portions 15b and 19b Inner diameter portions 16 and 20 Seal members 16a and 20a Side lips 16b and 20b Dustrips 16c and 20c Grease lip 17 Seal plate 18 Slinger 21 Nose portion 22 Labyrinth seal 23 Seal press-fit portion 23a Step 24 Press-fit guide portions 50 and 68 Seal 51, 71 Seal plate 52, 72 Slinger 3, 61, 61 'Outer member 53a, 61c Outer member end face 54, 73 Core metal 55, 74 Seal member 55a First side lip 55b Second side lip 55c, 74c Grease lip 56 Pressing jig 57 Tool body 57a Elastic member 57b Pressing surface 58 Pressing member 58a Recess 59 Holding jig 59a Holding surface 60, 63, 63 'Inner ring 61a Outer rolling surface 61b Car body mounting flange 62 Hub wheels 62a, 63a Inner rolling surface 62b Small diameter step 63a Inner ring outer peripheral surface 63b, 77a, T0 Step 64 Inner member 65 Cage 66 Ball 67 Outer side seal 68 Inner side seal 69 Wheel mounting flange 70 Encoder 74a Side lip 74b Grease lip 75 Nose part 77, 77 'seal Press-fit portion 78 Guide jig a Width of seal fitting portion b Width of seal press-fit portion d The insertion guide part and the nose part. D The inner diameter ΔD of the press-fitting guide part. The inner-diameter cross S of the press-fitting guide part. The radial clearance W0 between the press-fitting guide part and the fitting part of the cored bar. Width of press-fit guide part α Inclination angle of step in seal press-fit part β Inclination angle of press-fit guide part

Claims (8)

An outer member in which a double row outer rolling surface is integrally formed on the inner periphery;
An inner member in which a double row inner rolling surface facing the outer row rolling surface of the double row is formed on the outer periphery;
A double row rolling element housed movably between the rolling surfaces of the inner member and the outer member;
A seal for sealing both ends of the opening of the annular space formed between the inner member and the outer member;
Among these, the seal on the inner side is composed of a composite type seal composed of an annular seal plate and a slinger arranged to face each other,
The seal plate includes a core bar that is press-fitted into the inner periphery of the end of the outer member, and a seal member that is integrally joined to the core bar and integrally includes a side lip that extends at least in the radially outward direction. With
The slinger is formed in an L-shaped cross section, and has a cylindrical portion that is press-fitted into the outer periphery of the end portion of the inner member, and a standing plate portion that extends radially outward from the cylindrical portion. In the wheel bearing device in which the side lip is slidably contacted through a predetermined axial shimiro,
Opposite the outer diameter surface of the inner member between the seal press-fitting portion into which the seal is press-fitted into the inner periphery of the outer member end portion, and the seal press-fitting portion and the inner side end surface of the outer member. A wheel bearing device comprising a press-fitting guide portion formed at a position larger than the seal press-fitting portion.   The tip of the fitting portion of the metal core is formed thin, and the seal member is wrapped around and joined to cover the tip, and the outer peripheral surface thereof is larger than the outer diameter of the fitting portion of the metal core. The diameter nose portion is formed, a radial clearance is provided between the fitting portion of the core metal and the press-fitting guide portion, and the nose portion and the press-fitting guide portion have a shimoshiro. Wheel bearing device.   The wheel bearing device according to claim 2, wherein a squeeze between the nose part and the press-fitting guide part is set to 0 to 0.2 mm in diameter.   The wheel bearing device according to any one of claims 1 to 3, wherein a radial clearance between the fitting portion of the core metal and the press-fitting guide portion is set to 0 to 0.3 mm in diameter.   The tip of the fitting portion of the metal core is formed thin, and the seal member is wrapped around and joined to cover the tip, and the outer peripheral surface thereof is larger than the outer diameter of the fitting portion of the metal core. A nose portion having a diameter is formed, and the diameter of the nose portion and the press-fitting guide portion is set to -0.1 to 0.2 mm in diameter, and the diameter of the fitting portion of the core metal and the press-fitting guide portion The wheel bearing device according to claim 1, wherein the directional clearance is set to a diameter of 0 to 0.3 mm.   The wheel bearing device according to any one of claims 1 to 5, wherein an intersecting range of inner diameter dimensions of the press-fitting guide portion is set within ± 0.08 mm.   2. The wheel bearing device according to claim 1, wherein a step is formed between the seal press-fitting portion and the press-fitting guide portion. The step is formed of a tapered surface having an inclination angle of 10 to 45 ° that gradually increases in diameter toward the inner side.   The wheel bearing device according to claim 1, wherein the press-fitting guide portion is formed on a tapered surface having an inclination angle of 0 to 5 ° that gradually increases in diameter toward the inner side.

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