JP2017223253A - Manufacturing method of bearing device for wheel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely prevent intrusion of slurry and the like from a fitting portion of a sealing device.SOLUTION: A manufacturing method of a bearing device for a wheel in which a sealing device 60 mounted between an outer ring 11 and an inner ring 12 is a combined seal obtained by combining a seal ring 31 and a slinger 41, and the slinger 41 includes a cylindrical fixing portion 44 externally fitted to an outer peripheral face of the inner ring 12, is provided. The inner ring 12 is provided with an outer chamfer 40 on an inner-side end portion of the outer peripheral face, the slinger 41 has a projecting portion 48 projecting from the fixing portion 44 to an inner side, and a seal portion 49 composed of an elastic body is formed on an inner periphery of the projecting portion 48. The manufacturing method has a process for mounting the seal device 60 in a manner that at least a part of the seal portion 49 is radially opposed to the outer chamfer 40, and a caulking process for plastically deforming the projecting portion 48 to compress the sealing portion 49 with the outer chamber 40.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for manufacturing a wheel bearing device with improved muddy water resistance.

In the vehicle, a wheel bearing device 80 as shown in FIG. 5 is used to rotatably support the wheel.
The wheel bearing device 80 includes an outer ring 81 fixed to the knuckle 78 and an inner shaft 82 that is coaxial with the outer ring 81 and is rotatable. An annular space 83 formed between the inner periphery of the outer ring 81 and the outer periphery of the inner shaft 82 is open on both sides in the axial direction. Sealing devices 84 and 85 are attached to the respective openings to prevent foreign matters such as muddy water from entering the annular space 83. In FIG. 5, a wheel (not shown) is attached to the hub flange 86 provided at the shaft end of the inner shaft 82 from the left side. For this reason, the left side in FIG. 5 is referred to as the outer side, and the right side is referred to as the inner side.

The wheel bearing device 80 is required to have high muddy water resistance because it directly receives the muddy water and the like splashed by the wheel during traveling. For this reason, a combination seal in which a slinger 87 and a seal ring 88 are combined as shown in FIG. 6 is used for the inner side sealing device 85 attached to the inner side opening (Patent Document 1).
The slinger 87 is made of a stainless steel plate having an L-shaped cross section in the axial direction, and is attached to the outer peripheral surface of the inner ring 89 in an interference fit state. The seal ring 88 is formed by integrally forming a cored bar 90 made of a carbon steel plate having an L-shaped axial cross section and an elastic lip 91, and is attached to the inner peripheral surface of the outer ring 81 in a state of interference fit. Has been.

However, in the combination seal, the fitting portion between the slinger 87 and the inner ring 89 and the fitting portion between the seal ring 88 and the outer ring 81 are metal fittings. For this reason, when the fitting surface is rough or the fitting surface is scratched, a minute clearance is generated in the fitting portion, and muddy water or the like enters the bearing.
In the inner side sealing device 85 of Patent Document 1, the elastic body forming the lip 91 is extended to the outer periphery of the cored bar 90 in order to prevent water intrusion from the mating surfaces of the metals, and from the inner periphery of the outer ring 81. A large-diameter sealing portion 92 is formed.

Japanese Unexamined Patent Publication No. 2001-323944

  Thus, even with the inner side sealing device 85 in which the sealing portion 92 is provided and the elastic body is interposed between the fitting surfaces of the outer ring 81 and the cored bar 90, the wheel bearing device 80 used for a long time in the market. Then, there are cases where rust is generated in the fitting portion or muddy water enters the bearing.

  One possible cause is that when the seal ring 88 is attached to the outer ring 81, the sealing portion 92 formed on the outer periphery of the core metal 90 is scraped off on the inner periphery of the outer ring 81. This is because when the sealing portion 92 is scraped off, almost no interference of the elastic body remains between the sealing portion 92 and the inner periphery of the outer ring 81.

As another cause, it is conceivable that the core metal 90 and the slinger 87 are deformed when the inner side sealing device 85 is attached. For example, the cored bar 90 is integrally formed with a fixing part 93 attached to the outer ring 81 and a flange part 94 bent at a right angle inward in the radial direction, and the axial cross section is substantially L-shaped. . Since the flange portion 94 is formed on the outer side of the fixed portion 93, in the cored bar 90, the outer side has greater radial rigidity than the inner side.
As a result of CAE (Computer Aided Engineering) analysis of the seal ring 88 and the slinger 87 attached to the outer ring 81, the seal ring 88 is located on the side of the flange portion 94 as shown in FIG. And a gap s is generated at the mating portion with the outer ring 81.
Similarly, in the slinger 87, the inner side has a larger radial rigidity than the outer side, and when fitted to the inner ring 89, a clearance s is generated in the mating portion.
The actual deformation of the cored bar 90 and slinger 87 is negligible, and in FIG. 7, the size of each gap s is exaggerated for easy understanding.

  Due to these causes, muddy water or the like easily enters the fitting portion between the outer ring 81 and the seal ring 88 and the fitting portion between the inner ring 89 and the slinger 87, causing rust in the fitting portion, It is thought that muddy water enters the inside.

  Accordingly, the present invention provides a wheel bearing device having improved muddy water resistance by reliably preventing intrusion of muddy water from the fitting portion when a sealing device is mounted on the wheel bearing device. It is an object.

  One aspect of the present invention is arranged to be freely rollable between an outer ring having an outer raceway surface on the inner periphery, an inner ring having an inner raceway surface on the outer periphery, and the outer raceway surface and the inner raceway surface. And a sealing device for closing an inner opening end of an annular space formed between the outer ring and the inner ring, and a seal ring fixed to the outer ring, and fixed to the inner ring. The inner ring has a cylindrical outer peripheral surface closer to the inner side than the inner raceway surface, and the slinger has a cylindrical fixing portion that is externally fitted to the outer peripheral surface. In the inner ring, the inner ring is formed with an outer chamfer at the inner side end portion of the outer peripheral surface, the outer chamfer being reduced in diameter toward the end surface. To the inner side with the same axis A cylindrical projecting portion is integrally formed, and an inner periphery of the projecting portion is integrally formed with a sealing portion made of an elastic body, and at least a part of the sealing portion is formed on the outer surface. A mounting step of mounting the sealing device so as to oppose the chamfer in a radial direction; and the sealing portion between the protrusion and the outer chamfer by plastically deforming the protrusion along the outer chamfer. And a caulking step for compressing.

  In another aspect of the present invention, an outer ring having an outer raceway surface on the inner periphery, an inner ring having an inner raceway surface on the outer periphery, and a rollable arrangement between the outer raceway surface and the inner raceway surface. A plurality of rolling elements, and a sealing device for closing an inner opening end of an annular space formed between the outer ring and the inner ring includes a seal ring fixed to the outer ring, and the inner ring The outer ring has a cylindrical inner peripheral surface closer to the inner side than the outer raceway surface, and the seal ring is a cylindrical shape that is internally fitted on the inner peripheral surface. In the outer ring, an inner surface chamfer is formed on the inner side end portion of the inner peripheral surface, the diameter of which increases toward the end surface. The ring is coaxial with the fixed part. A cylindrical projecting portion extending to the side is integrally formed, and a sealing portion made of an elastic body is integrally formed on the outer periphery of the projecting portion, and at least a part of the sealing portion Mounting the sealing device so as to face the inner surface in the radial direction, and plastically deforming the protrusion along the inner surface, so that the protrusion and the inner surface And a caulking step for compressing the sealing portion.

  According to the present invention, when the sealing device is attached to the wheel bearing device, it is possible to reliably prevent the intrusion of muddy water or the like from the fitting portion. For this reason, the bearing apparatus for wheels which improved muddy water resistance performance can be provided.

It is a principal part enlarged view of one Embodiment of the wheel bearing apparatus concerning this invention. It is a principal part enlarged view of the seal ring fitting part before caulking. It is a principal part enlarged view of the slinger joint part before caulking. It is explanatory drawing explaining the method to mount | wear with an inner side sealing device. It is sectional drawing of the conventional wheel bearing apparatus. It is sectional drawing of the sealing device with which the inner side of the conventional wheel bearing apparatus is mounted | worn. It is a schematic diagram explaining the mounting state of a sealing device.

Embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is an enlarged view of a main part of an embodiment (hereinafter referred to as “this embodiment”) of a wheel bearing device 10 according to the present invention, and a sealing device 60 (hereinafter simply referred to as “inner side sealing device” mounted on an inner side). )). The wheel bearing device 10 according to the present embodiment is characterized by the form of the inner side sealing device 60 and the shape of the mating portion of the outer ring 11 and the inner ring 12 to which the inner side sealing device 60 is fitted. Since the other forms are the same as those of the conventional wheel bearing device 80, portions common to the conventional structure will be described with the same reference numerals with reference to FIG.
In the following description, the direction of the axis m is referred to as the axial direction, the direction orthogonal to the axial direction is referred to as the radial direction, and the direction of circling around the axis m is referred to as the circumferential direction.

  The wheel bearing device 10 of this embodiment includes an outer ring 11, an inner shaft 20, a plurality of balls 21 that are rolling elements, an inner side sealing device 60, and an outer side sealing device 84.

  The outer ring 11 is manufactured by hot forging or the like of high carbon steel, and a substantially cylindrical cylindrical portion 13 and a flange portion 14 formed on the outer periphery thereof are integrally formed. The flange portion 14 extends radially outward from substantially the center in the axial direction at a plurality of locations on the outer periphery of the cylindrical portion 13. A bolt hole 15 penetrating in the axial direction is formed in the flange portion 14. When the wheel bearing device 10 is mounted on a vehicle, after the cylindrical portion 13 is inserted into the mounting hole of the knuckle 78, a bolt (not shown) is inserted into the bolt hole 15, and the outer ring 11 is fixed to the knuckle 78. ing. The side surface on the inner side of each flange portion 14 is formed flush with the axis m and is in contact with the mounting surface of the knuckle 78.

  Two rows of outer raceway surfaces 16, 16 are formed on the inner periphery of the cylindrical portion 13 at substantially the center in the axial direction. The outer raceway surfaces 16 and 16 are each formed in an annular shape coaxial with the axis m, with an axial cross section having an arc shape. The outer raceway surfaces 16, 16 are subjected to heat treatment to increase the surface hardness to about 60HRC, and then subjected to grinding.

A seal mounting surface 23 is formed at the outer side end of the inner periphery of the cylindrical portion 13. The seal mounting surface 23 is a cylindrical surface coaxial with the axis m, and the outer side sealing device 84 is assembled thereto.
The outer side sealing device 84 includes a metal cored bar and a sealing lip made of an elastic body. The core metal is formed in an annular shape with a substantially L-shaped cross section by press-molding a thin cold rolled steel plate such as SPCC. A rubber material such as nitrile rubber or acrylic rubber is used as the material of the seal lip. The seal lip is vulcanized with a high-temperature mold and simultaneously vulcanized and bonded to the core metal.

  Please refer to FIG. A seal attachment surface 24 is formed on the inner peripheral side of the inner end of the cylindrical portion 13. The seal mounting surface 24 is a cylindrical surface coaxial with the axis m, and the inner side sealing device 60 is assembled thereto. On the inner side of the seal mounting surface 24, an inner surface chamfer 30 is formed in which the inner periphery expands in a tapered shape toward the outer ring end surface 63. The inner side sealing device 60 will be described later.

This will be described with reference to FIG.
The inner shaft 20 has a configuration in which the hub shaft 19 and the inner ring 12 are combined together. The hub shaft 19 is manufactured by hot forging high carbon steel and has a stepped cylindrical shaft portion 18 extending in the direction of the axis m. A disc-shaped hub flange 86 that extends in a direction orthogonal to the axis m is integrally formed at the outer shaft end of the shaft portion 18.

On the outer periphery of the shaft portion 18, a first inner raceway surface 26 is formed in an annular shape coaxial with the axis m at approximately the center in the axial direction. The first inner raceway surface 26 has an arc-shaped cross section in the axial direction, and is subjected to heat treatment to increase the surface hardness to about 60 HRC, and then subjected to grinding.
A large-diameter shoulder 27 is formed on the outer side from the first inner raceway surface 26. The outer peripheral surface of the shoulder 27 is a cylindrical surface coaxial with the axis m, and on the outer side of the shoulder 27, the axial cross section is connected to the hub flange 86 at an arcuate R portion. The outer peripheral surface of the large diameter shoulder 27 and the R portion is ground, and the lip of the outer side sealing device 84 is in sliding contact.
A small-diameter stepped portion is formed at the inner side end of the shaft portion 18, and the inner ring 12 is assembled in a state of an interference fit.

  A plurality of hub bolts 22 are installed on the hub flange 86 at equal intervals in the circumferential direction so as to penetrate in the axial direction. A wheel of a wheel (not shown) is attached to the outer side surface of the hub flange 86 and fixed with the hub bolt 22. A substantially cylindrical guide portion 17 is formed at the center of the outer side surface. By fitting the wheel to the guide portion 17, the wheel and the hub shaft 19 are assembled so as to be coaxial with each other.

The inner ring 12 is made of bearing steel, and a second inner raceway surface 28 is formed in an annular shape coaxial with the axis m at a substantially axial center of the outer periphery. The second inner raceway surface 28 has an arc-shaped cross section in the axial direction. A large-diameter shoulder 29 is formed on the inner side of the second inner raceway surface 28 (see FIG. 1). The outer periphery of the shoulder 29 is a cylindrical surface coaxial with the axis m, and the inner side sealing device 60 is assembled. An outer chamfer 40 that is tapered toward the inner ring end face 64 is formed at the inner end of the outer periphery of the shoulder 29.
The inner ring 12 is subjected to heat treatment to increase the surface hardness to about 60 HRC, and then the outer peripheral surfaces of the second inner raceway surface 28 and the shoulder 29 are ground.

A plurality of balls 21 are rotatably incorporated between the outer raceway surfaces 16 and 16 and the inner raceway surfaces 26 and 28 that are opposed to each other in the radial direction. The balls 21 in each row are arranged at equal intervals in the circumferential direction by the cage 25. Grease is sealed in an annular space 83 formed between the outer ring 11 and the inner shaft 20 in order to lubricate each raceway surface. Thus, the inner shaft 20 is supported rotatably with respect to the outer ring 11.
The annular space 83 is open on both sides in the axial direction, and the inner side sealing device 60 is mounted on the inner side opening, and the outer side sealing device 84 is mounted on the outer side opening.

  The inner side sealing device 60 will be described with reference to FIGS. 1 to 3. The inner side sealing device 60 includes a seal ring 31 and a slinger 41. In FIG. 1, the inner side end part of the metal core 32 and the inner side end part of the slinger 41 constituting the seal ring 31 are shown assembled by caulking. 2 and 3 are enlarged views of main parts of the seal ring fitting portion and the slinger fitting portion, respectively, and show the form of the seal ring 31 and the slinger 41 before the caulking process.

With reference to FIG. 1 and FIG. 2, the form of the seal ring 31 is demonstrated.
The seal ring 31 includes a metal cored bar 32 and a plurality of lips 33, 34, and 35 made of an elastic body.
The core metal 32 is formed in an annular shape by press-molding a thin cold-rolled steel plate such as SPCC. The metal core 32 includes a cylindrical fixing portion 36, and an end portion on the outer side of the fixing portion 36 is bent at a right angle inward in the radial direction to form a seal holding portion 37. The fixed portion 36 has a larger outer diameter than the inner diameter of the seal mounting surface 24. For this reason, when the seal ring 31 is assembled to the outer ring 11, the seal ring 31 is assembled in a state of interference fit.

The lip 33, 34, 35 is formed integrally with the seal holding portion 37. A grease lip 33 is in contact with the outer periphery of the slinger 41 with a small interference to prevent the grease sealed in the annular space 83 from flowing out. Reference numeral 34 denotes a radial lip which is in sliding contact with the outer periphery of the slinger 41 and prevents foreign matter from entering the annular space 83 and prevents the grease from flowing out of the annular space 83. An axial lip 35 is in sliding contact with the flange 47 of the slinger 41 to prevent foreign matters such as muddy water and dust from reaching the radial lip 34 directly.
As the material of each lip 33, 34, 35, a rubber material such as nitrile rubber or acrylic rubber is used. Each lip 33, 34, and 35 is vulcanized and molded with a high-temperature mold and is vulcanized and bonded to the seal holding portion 37.

A protruding portion 38 (hereinafter referred to as a “core metal protruding portion”) extending toward the inner side is integrally formed at an end portion of the fixing portion 36 opposite to the seal holding portion 37 (see FIG. 2). The cored bar protruding portion 38 has a cylindrical shape that is coaxial with the fixed portion 36. The outer diameter dimension of the cored bar protruding portion 38 is smaller than the outer diameter dimension of the fixed portion 36.
On the outer periphery of the cored bar protruding portion 38, a sealing portion 39 is uniformly formed over the entire circumference. The sealing portion 39 is made of the same rubber material as the lips 33, 34, and 35, and is integrally formed with the lips 33, 34, and 35 by vulcanization and is vulcanized and bonded to the core metal protruding portion 38. Yes. The sealing part 39 includes a base part 42 having an outer diameter dimension substantially the same as the outer diameter dimension of the fixed part 36, and a convex part 43 protruding outward in the radial direction. The convex portion 43 is formed at the center in the axial direction of the base portion 42, and the outer diameter dimension thereof is larger than the outer diameter dimension of the fixed portion 36.

The form of the slinger 41 will be described with reference to FIGS.
The slinger 41 is formed in an annular shape by press molding a stainless steel plate. The slinger 41 is L-shaped in cross section and has a fixing portion 44 that extends in a cylindrical shape in the axial direction. The fixed portion 44 has a double cylindrical structure that is folded back in the axial direction and closely adhered in the radial direction. The inner circumferential side cylindrical portion 45 (hereinafter referred to as “inner cylindrical portion”) is open to the inner side, and the outer side end is connected to the outer circumferential side cylindrical portion 46 (hereinafter referred to as “outer cylindrical portion”). In the outer cylindrical portion 46, a flange portion 47 extending in the radial direction is formed by bending the inner side end portion at a right angle outward in the radial direction. The inner cylindrical portion 45 has an inner peripheral diameter smaller than the outer diameter of the shoulder 29. For this reason, when the slinger 41 is assembled to the inner ring 12, it is assembled in a state of interference fit.

A projecting portion 48 extending to the inner side (hereinafter referred to as “slinger projecting portion”) is integrally formed at the inner side end portion of the inner cylindrical portion 45 (see FIG. 3). The slinger protruding portion 48 is coaxial with the inner cylindrical portion 45 and has a cylindrical shape. The inner diameter dimension of the slinger projecting portion 48 is larger than the inner diameter dimension of the inner cylindrical portion 45.
A sealing portion 49 is formed on the inner periphery of the slinger protrusion 48. The sealing portion 49 is formed of an elastic body such as nitrile rubber or acrylic rubber, and is attached to the slinger protrusion 48 by vulcanization adhesion. The sealing portion 49 is uniformly formed on the inner periphery of the slinger protruding portion 48 over the entire circumference, and protrudes inward in the radial direction, with a base portion 50 having an inner diameter dimension substantially the same as the inner diameter dimension of the inner cylindrical portion 45. And the convex portion 51. The convex portion 51 is formed at the center in the axial direction of the base portion 50, and the inner diameter dimension of the convex portion 51 is smaller than the inner diameter dimension of the inner cylindrical portion 45.

  The slinger 41 may be equipped with an encoder 52 formed of a rubber magnet. In FIG. 1, a form in which the encoder 52 is mounted is indicated by a one-dot chain line. The encoder 52 has a disc shape and is coaxially attached to the side surface of the flange portion 47 by vulcanization adhesion or the like. The surface of the encoder 52 is magnetized, and S poles and N poles are alternately formed in the circumferential direction. In this case, the slinger 41 is made of a thin cold-rolled steel plate such as SPCC.

  Next, a method for manufacturing the wheel bearing device 10 will be described. The manufacturing method of the present embodiment includes a mounting process 61 for mounting the inner side sealing device 60 and a caulking process 66 for plastically deforming the protrusions 38 and 48. FIG. 4 is an explanatory diagram for explaining a method of mounting the inner side sealing device 60, and shows a state in which the jig 62 is in contact with the core metal 32 and the slinger 41.

  In the mounting step 61, the inner side sealing device 60 is mounted on the inner side opening end of the annular space 83. At this time, the inner side sealing device 60 is disposed coaxially with the annular space 83 in a state where the seal ring 31 faces the opening of the annular space 83 in a combined state as shown in FIG. Thereafter, the inner ring sealing device 60 is mounted by pressing the seal ring 31 and the slinger 41 in the axial direction at the same time.

The mounting operation is performed using the jig 62. The jig 62 includes an A surface and a B surface that are formed at different positions in the axial direction and in a direction orthogonal to the axis m. The A surface simultaneously presses the inner side end surface of the core metal protruding portion 38 of the core metal 32, and the B surface simultaneously presses the inner side surface of the flange portion 47 of the slinger 41. The axial displacement amount of the seal ring 31 and the slinger 41 can be set in accordance with the displacement amount L1 between the A surface and the B surface in the axial direction. Thereby, the axial direction interference of the collar part 47 and the axial lip 35 can be set to an optimal magnitude | size.
In this way, the seal ring 31 is press-fitted into the inner periphery of the outer ring 11 and simultaneously the slinger 41 is press-fitted into the outer periphery of the inner ring 12. In addition, in the slinger 41, the inner side end face of the slinger protrusion 48 may be pressed instead of the flange 47 by appropriately changing the axial position of the B surface.

Next, the state of the fitting portion in the mounting step 61 will be described in more detail with reference to FIGS.
In the sealing portion 39 of the seal ring 31, the outer diameter size of the base portion 42 is equal to the outer diameter size of the fixed portion 36. For this reason, the outer periphery of the fixed part 36 is in strong contact with the inner periphery of the outer ring 11, and the outer periphery of the base part 42 is not in contact with the inner periphery of the outer ring 11, or is in contact with the contact surface. Is extremely small. For this reason, the base 42 is not scraped off by the inner periphery of the outer ring 11.

Further, when the seal ring 31 is press-fitted into the outer ring 11 until the A surface (see FIG. 4) of the jig 62 and the outer ring end surface 63 come into contact with each other, the inner side end surface of the cored bar protrusion 38 and the outer ring end surface of the outer ring 11 are used. 63 becomes flush. In the seal ring 31, the axial length of the cored bar protruding portion 38 is substantially equal to the axial length of the inner surface chamfer 30, so that the cored bar protruding portion 38 and the inner surface chamfer 30 face each other in the radial direction.
The convex portion 43 is formed at a position away from the position of the minimum diameter of the inner surface chamfer 30 (indicated by P1 in FIG. 2) toward the outer ring end surface 63 side. On the other hand, the inner surface chamfer 30 increases in diameter as it goes from P <b> 1 toward the outer ring end surface 63, so the convex portion 43 does not contact the inner surface chamfer 30.
For this reason, in the mounting step 61, the sealing portion 39 of the seal ring 31 is not scraped off by the inner periphery of the outer ring 11. When the seal ring 31 is mounted, the convex portion 43 faces the inner surface chamfer 30 in the radial direction.

Similarly, the slinger 41 can be attached to the shoulder 29 of the inner ring 12. This will be described with reference to FIG.
In the sealing part 49 of the slinger 41, the inner diameter dimension of the base part 50 is equal to the inner diameter dimension of the inner cylindrical part 45. For this reason, the inner circumference of the inner cylindrical portion 45 is in strong contact with the shoulder 29, and the inner circumference of the base portion 50 is not in contact with the shoulder 29, or even when in contact, the contact pressure on the contact surface is extremely small. . For this reason, the base 50 is not scraped off by the shoulder 29.

Further, the slinger 41 is accurately assembled in the axial direction by the jig 62 with reference to the seal ring 31 (see FIG. 4). Thereby, the slinger protrusion 48 is mounted at a position facing the outer chamfer 40 in the radial direction.
The convex portion 51 is formed at a position away from the position of the maximum diameter of the outer chamfer 40 (indicated by P2 in FIG. 3) toward the inner ring end face 64 side. On the other hand, since the outer chamfer 40 is reduced in diameter toward the inner ring end face 64, the convex portion 51 does not contact the outer chamfer 40.
For this reason, in the mounting step 61, the sealing portion 49 of the slinger 41 is not scraped off by the shoulder 29 of the inner ring 12. When the slinger 41 is mounted, the convex portion 51 faces the outer chamfer 40 in the radial direction.

  Next, the caulking process 66 will be described. In the present embodiment, the caulking process 66 includes a caulking process 67 for caulking the core metal protrusion 38 (core metal caulking process) and a caulking process 68 for caulking the slinger protrusion 48 (slinger caulking process). 67 and 68 are performed individually.

  In the mandrel caulking process 67, the mandrel protrusion 38 is urged toward the inner surface chamfer 30 in the direction indicated by the white arrow G in FIG. As a caulking method, a roll caulking method in which a die (not shown) is pressed against a part of the core metal protrusion 38 and the outer ring 11 is rotated while being plastically deformed radially outward to sequentially deform in the circumferential direction. Alternatively, a caulking method or the like that presses a tapered jig (not shown) and plastically deforms the entire cored bar protruding portion 38 radially outward is used as appropriate.

At the time of caulking, the cored bar protrusion 38 is plastically deformed into a shape along the inner surface chamfer 30 as shown in FIG. At this time, the cored bar protrusion 38 bends at a position P1 (see FIG. 2) where the seal mounting surface 24 and the inner surface chamfer 30 are connected. On the outer periphery of the cored bar protruding portion, a convex portion 43 protrudes radially outward over the entire circumference. The convex portion 43 is displaced so as to draw an arc around P 1, and approaches the inner surface chamfer 30.
Thus, the convex portion 43 is compressed in the height direction (perpendicular to the core metal projection portion 38) by the inner surface chamfer 30 and the core metal projection portion 38. Since almost no load acts in the shearing direction (the direction parallel to the cored bar protruding portion 38) with respect to the convex portion 43, even if the height H1 of the convex portion 43 is relatively high, It can be assembled securely.

  Thus, in the present embodiment, the sealing portion 39 can be reliably assembled by being compressed in the height direction at the fitting portion between the core metal 32 of the seal ring 31 and the inner periphery of the outer ring 11.

  On the other hand, in the conventional inner side sealing device 85 as shown in FIG. 6, the seal ring 88 is merely fitted to the outer ring 81 in the axial direction. Therefore, at the time of press-fitting, the sealing portion 92 is urged from the outer ring 81 in the axial direction (left-right direction in FIG. 6). For this reason, a shearing force acts and the sealing part 92 is easily damaged. Thus, the sealing portion 92 is scraped away by the outer ring 81. In particular, when the height H3 of the sealing portion 92 is increased, it becomes easier to receive an axial force from the outer ring 81, and the assembly of the seal ring 88 becomes more difficult. For this reason, in the conventional structure, the sealing portion 92 cannot be reliably assembled by being compressed in the radial direction.

On the other hand, in the present embodiment, the convex portion 43 is assembled by being compressed in the height direction by the inner surface chamfer 30 and the cored bar protruding portion 38, and is loaded in the compression direction with respect to the sealing portion 39. Is working. In general, in an elastic body such as rubber, the compressive strength is higher than the shear strength, and the sealing portion 39 is not likely to be damaged.
Thus, in the present embodiment, the sealing portion 39 formed of an elastic body can be reliably assembled by compressing in the height direction. Therefore, muddy water or the like can be reliably prevented from entering the bearing from the fitting portion between the outer ring 11 and the seal ring 31.

In the slinger caulking step 68, the slinger protrusion 48 is biased toward the outer chamfer 40 in the direction indicated by the white arrow F in FIG. As a caulking method, the slinger protrusion 48 is plastically deformed inward in the radial direction by the same method as in the core bar caulking step 67.
At the time of caulking, as shown in FIG. 1, the slinger protrusion 48 is plastically deformed into a shape along the outer chamfer 40. At this time, the slinger protrusion 48 bends at a position P2 (see FIG. 3) where the outer periphery of the shoulder 29 and the outer chamfer 40 are connected. On the inner periphery of the slinger protrusion 48, a convex portion 51 protrudes radially inward over the entire periphery. The convex portion 51 is displaced so as to draw an arc around P 2 and approaches the outer chamfer 40.
Thus, the protrusion 51 is compressed in the height direction (perpendicular to the slinger protrusion 48) by the outer chamfer 40 and the slinger protrusion 48. Since almost no load acts on the convex portion 51 in the shearing direction (the direction parallel to the slinger protruding portion 48), it is easy and reliable even when the height H2 of the convex portion 51 is relatively high. Can be assembled.

  Thus, in this embodiment, the sealing portion 49 formed of an elastic body can be reliably assembled by compressing in the height direction. Therefore, muddy water or the like can be reliably prevented from entering the inside of the bearing from the fitting portion between the slinger 41 and the shoulder 29 of the inner ring 12.

Further, in the core metal 32 and the slinger 41, the seal holding portion 37 and the flange portion 47 are formed on one side in the axial direction, respectively, so that the radial rigidity is greatly different between the inner side and the outer side. For this reason, as shown in FIG. 7, a clearance s is generated at the mating portion with the outer ring 11 or the inner ring 12.
However, in this embodiment, the cored bar protruding portion 38 and the slinger protruding portion 48 are bent and assembled in a state where the sealing portions 39 and 49 are compressed. The height at which the sealing portions 39 and 49 protrude in the radial direction (corresponding to the heights H1 and H2 of the convex portions 43 and 51) is much larger than the gap s. For this reason, even if the above-described gap s exists, each sealing portion can be reliably assembled by being compressed in the height direction. Therefore, muddy water or the like can be reliably prevented from entering the bearing from the fitting portion.

  In the caulking process according to the present embodiment, the protrusions 38 and 48 are plastically deformed along the inner chamfer 30 and the outer chamfer 40, respectively. Therefore, even if the size and position of the chamfers 30 and 40 change due to processing variations, the sealing portions 39 and 49 can be reliably assembled by compressing in the height direction. Therefore, the muddy water resistance does not change due to variations in the shapes of the chamfers 30 and 40, and muddy water or the like can be reliably prevented from entering the bearing from the fitting portion.

  Moreover, in this embodiment, when the inner side sealing device 60 is assembled | attached, the convex parts 43 and 51 are formed in the position away from P1 or P2. For this reason, the convex portions 43 and 51 are not in contact with the inner peripheral surface of the outer ring 11 or the outer peripheral surface of the shoulder 29 of the inner ring 12. However, it does not exclude all these contacts. For example, a part of the convex portions 43 and 51 may contact the seal mounting surface 24 of the outer ring 11 or the outer peripheral surface of the shoulder 29 of the inner ring 12. The other part of the convex portions 43 and 51 is opposed to the chamfers 30 and 40 in the radial direction, and when the convex portions 43 and 51 are not shaved, the convex portion 43 is subjected to caulking. , 51 can be securely assembled by compressing them in the height direction. Therefore, it is possible to reliably prevent muddy water or the like from entering the inside of the bearing from the joint portion of the core metal 32 and the slinger 41.

  In this embodiment, both the seal ring 31 and the slinger 41 are caulked. However, the present invention is not limited to this, and caulking may be performed on only one of them.

  As described above, according to the assembling method of the present embodiment, when the inner side sealing device 60 is attached to the wheel bearing device 10, the fitting portion between the seal ring 31 and the outer ring 11, and the slinger 41 and the inner ring. 12 can be reliably incorporated into the fitting portion without damaging the sealing portion 39. For this reason, it can prevent reliably that muddy water etc. permeate into the inside of a bearing from the said fitting part. Thereby, the bearing device for wheels which improved muddy water resistance performance can be provided.

(This embodiment) 10: Wheel bearing device, 11: Outer ring, 12: Inner ring, 14: Flange, 16: Outer raceway surface, 19: Hub shaft, 20: Inner shaft, 21: Ball, 24: Seal mounting surface (Inner), 25: cage, 26: first inner raceway surface, 28: second inner raceway surface, 29: shoulder (inner ring), 30: inner chamfer, 31: seal ring, 32: cored bar, 36: fixed Part, 37: seal holding part, 38: cored bar protruding part, 39: sealing part, 40: outer chamfering, 41: slinger, 42: base part, 43: convex part, 44: fixing part, 45: inner cylindrical part, 46: outer cylindrical part, 47: collar part, 48: slinger protruding part, 49: sealing part, 50: base part, 51: convex part, 60: inner side sealing device, 61: mounting step, 62: jig, 66 : Caulking process, 78: knuckle,
(Prior art) 80: bearing device for wheels, 81: outer ring, 82: inner shaft, 83: annular space, 84: sealing device (outer), 85: sealing device (inner), 86: hub flange, 87: slinger 88: Seal ring, 89: Inner ring, 90: Core, 91: Lip, 92: Sealing part, 93: Fixing part, 94: Gutter part

Claims (2)

An outer ring having an outer raceway surface on the inner periphery, an inner ring having an inner raceway surface on the outer periphery, and a plurality of rolling elements arranged to roll between the outer raceway surface and the inner raceway surface; With
The sealing device that closes the inner opening end of the annular space formed between the outer ring and the inner ring is a combination seal that combines a seal ring fixed to the outer ring and a slinger fixed to the inner ring. And the inner ring has a cylindrical outer peripheral surface closer to the inner side than the inner raceway surface, and the slinger has a cylindrical fixing portion that is externally fitted to the outer peripheral surface. Because
In the inner ring, an outer chamfer that is reduced in diameter toward the end surface is formed on the inner side end of the outer peripheral surface,
The slinger has a cylindrical projecting portion that is coaxial with the fixed portion and extends toward the inner side, and a sealing portion made of an elastic body is integrally formed on the entire circumference of the projecting portion. Has been
A mounting step of mounting the sealing device so that at least a part of the sealing portion faces the outer chamfer in a radial direction;
A caulking process for compressing the sealing portion between the protruding portion and the outer chamfer by plastically deforming the protruding portion along the outer chamfering, and a method for manufacturing a wheel bearing device. An outer ring having an outer raceway surface on the inner periphery, an inner ring having an inner raceway surface on the outer periphery, and a plurality of rolling elements arranged to roll between the outer raceway surface and the inner raceway surface; With
The sealing device that closes the inner opening end of the annular space formed between the outer ring and the inner ring is a combination seal that combines a seal ring fixed to the outer ring and a slinger fixed to the inner ring. And the outer ring has a cylindrical inner peripheral surface closer to the inner side than the outer raceway surface, and the seal ring includes a cylindrical fixing portion that is internally fitted on the inner peripheral surface. A manufacturing method of
In the outer ring, an inner surface chamfer that increases in diameter toward the end surface is formed at the inner side end of the inner peripheral surface,
The seal ring has a cylindrical projecting portion that is coaxial with the fixed portion and extends toward the inner side, and a sealing portion made of an elastic body is integrally formed on the outer periphery of the projecting portion. Has been
A mounting step of mounting the sealing device so that at least a part of the sealing portion faces the inner surface in the radial direction;
And a caulking step of compressing the sealing portion between the protrusion and the inner surface by plastically deforming the protrusion along the inner surface.

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