JP6740734B2 - Manufacturing method of bearing device for wheel - Google Patents

Description

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

In a vehicle, a wheel bearing device 80 as shown in FIG. 5 is used to rotatably support the wheels.
The wheel bearing device 80 includes an outer ring 81 fixed to the knuckle 78 and an inner shaft 82 that is rotatable coaxially with the outer ring 81. An annular space 83 formed between the inner circumference of the outer ring 81 and the outer circumference 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 matter such as muddy water from entering the annular space 83. In FIG. 5, a wheel (not shown) is attached from the left side to a hub flange 86 provided at the shaft end of the inner shaft 82. Therefore, the left side of FIG. 5 is called the outer side and the right side is called the inner side.

In the wheel bearing device 80, high muddy water resistance is required because the muddy water splashed up by the wheels during running is directly exposed to water. For this reason, a combination seal as shown in FIG. 6 in which a slinger 87 and a seal ring 88 are combined is used for the inner sealing device 85 mounted in the opening on the inner side (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 mounted on the outer peripheral surface of the inner ring 89 in an interference fit state. The seal ring 88 is integrally formed with a core bar 90 made of a carbon steel plate having an L-shaped cross section in the axial direction and an elastic lip 91, and is attached to the inner peripheral surface of the outer ring 81 in an interference fit state. Has been done.

However, in the combined seal, the fitting portion of the slinger 87 and the inner ring 89 and the fitting portion of the seal ring 88 and the outer ring 81 are metal-to-metal fittings. For this reason, when the fitting surface is rough or the fitting surface is scratched, a small gap is generated in the fitting portion, so that muddy water or the like enters the inside of the bearing.
In the inner sealing device 85 of Patent Document 1, the elastic body forming the lip 91 is extended to the outer circumference of the core metal 90 to prevent water from entering from the mating surfaces of the metals, and the inner circumference of the outer ring 81 is A large-diameter sealing portion 92 is formed.

JP, 2001-323942, A

Thus, even with the inner side sealing device 85 in which the sealing portion 92 is provided and the elastic surface is interposed between the fitting surfaces of the outer ring 81 and the core metal 90, the wheel bearing device 80 has been used for a long time in the market. Then, there is a case where rust is generated in the fitting portion or muddy water enters the inside of the bearing.

As one of the causes for this, it is conceivable that when the seal ring 88 is attached to the outer ring 81, the sealing portion 92 formed on the outer periphery of the cored bar 90 is scraped off on the inner periphery of the outer ring 81. This is because when the sealing portion 92 is scraped off, the interference of the elastic body hardly remains between the sealing portion 92 and the inner circumference of the outer ring 81.

Further, as another cause, it is conceivable that the core metal 90 and the slinger 87 are deformed when the inner sealing device 85 is mounted. For example, the cored bar 90 is integrally formed with a fixed part 93 mounted on the outer ring 81 and a flange part 94 bent at a right angle inward in the radial direction, and has an approximately L-shaped cross section in the axial direction. .. Since the flange portion 94 is formed on the outer side of the fixed portion 93, the core bar 90 has a greater radial rigidity on the outer side than on the inner side.
The seal ring 88 and the slinger 87 mounted on the outer ring 81 are analyzed by CAE (Computer Aided Engineering). As a result, as shown in FIG. 7, the seal ring 88 has the outer ring 81 on the side of the collar portion 94. However, there is a clearance s at the joint with the outer ring 81.
Similarly, in the slinger 87, the inner side has greater radial rigidity than the outer side, and when fitted to the inner ring 89, a clearance s is formed in the mating portion.
The actual deformations of the core metal 90 and the slinger 87 are very small, and the size of each clearance s is exaggerated in FIG. 7 for easy understanding.

Due to these causes, muddy water and the like easily enter 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, and the fitting portion is rusted or the bearing is damaged. It is thought that muddy water may enter inside.

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

According to one aspect of the present invention, an outer ring having an outer raceway surface on an inner circumference, an inner race having an inner raceway surface on an outer circumference, and a rollable arrangement between the outer raceway surface and the inner raceway surface. A sealing device that includes a plurality of rolling elements and closes an inner opening end of an annular space formed between the outer ring and the inner ring, and a sealing ring fixed to the outer ring and fixed to the inner ring. The inner ring has a cylindrical outer peripheral surface on the inner side from the inner raceway surface, and the slinger has a cylindrical fixed portion externally crimped on the outer peripheral surface. A method of manufacturing a bearing device for a wheel, comprising: in the inner race, an inner chamfer of the outer peripheral surface is formed with an outer chamfer whose diameter decreases toward the end surface, and in the slinger, the fixing is performed. Has a cylindrical projecting portion coaxially extending to the inner side, and a sealing portion made of an elastic body is integrally formed over the entire circumference on the inner periphery of the projecting portion. A mounting step of mounting the sealing device so that at least a part of the stop portion faces the outer chamfer in the radial direction, and the protruding portion and the outer surface by plastically deforming the protruding portion along the outer chamfer. And a caulking step of compressing the sealing portion between the removal and the removal.

According to another aspect of the present invention, an outer ring having an outer raceway surface on an inner circumference, an inner race having an inner raceway surface on an outer circumference, and a rollable arrangement between the outer raceway surface and the inner raceway surface. A plurality of rolling elements, which closes the inner side opening end of the annular space formed between the outer ring and the inner ring, and a sealing ring fixed to the outer ring and the inner ring. It is a combination seal in which a slinger to be fixed is combined, wherein the outer ring has a cylindrical inner peripheral surface on the inner side from the outer raceway surface, and the seal ring is a cylindrical shape that is internally hardened on the inner peripheral surface. In the outer ring, an inner chamfer whose diameter increases toward the end surface is formed at the inner side end portion of the inner peripheral surface of the outer ring. The ring integrally has a cylindrical protruding portion that extends coaxially with the fixing portion and extends toward the inner side, and a sealing portion made of an elastic body is integrally formed over the entire circumference on the outer periphery of the protruding portion. And a mounting step of mounting the sealing device so that at least a part of the sealing portion faces the inner chamfer in the radial direction, and the projecting portion is plastically deformed along the inner chamfer to thereby project the protrusion. And a caulking step of compressing the sealing portion between the portion and the inner chamfer.

According to the present invention, when the sealing device is mounted on the wheel bearing device, it is possible to reliably prevent the entry of muddy water or the like from the fitting portion. Therefore, it is possible to provide a bearing device for a wheel with improved muddy water resistance.

It is a principal part enlarged view of one Embodiment of the bearing device for wheels concerning this invention. It is a principal part enlarged view of the seal ring fitting part before crimping. It is a principal part enlarged view of the slinger joint part before crimping. It is explanatory drawing explaining the method of mounting an inner side sealing device. It is sectional drawing of the conventional bearing device for wheels. It is sectional drawing of the sealing device mounted in the inner side of the conventional wheel bearing apparatus. 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, this embodiment) of a wheel bearing device 10 according to the invention. A sealing device 60 mounted on an inner side (hereinafter, simply referred to as “inner side sealing device”) ") is incorporated. The wheel bearing device 10 of the present embodiment is characterized by the form of the inner side sealing device 60 and the form of the joint portion of the outer ring 11 and the inner ring 12 into which the inner side sealing device 60 is fitted. Since other aspects 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. 5.
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 around the axis m is referred to as the circumferential direction.

The wheel bearing device 10 of the present 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 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 circumference of the cylindrical portion 13. The flange portion 14 is formed with a bolt hole 15 penetrating in the axial direction. When mounting the wheel bearing device 10 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 to fix the outer ring 11 to the knuckle 78. ing. The inner side surface of each flange portion 14 is formed so as to be flush with the axis m and is in contact with the mounting surface of the knuckle 78.

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

A seal mounting surface 23 is formed at the outer end of the inner circumference of the cylindrical portion 13. The seal mounting surface 23 is a cylindrical surface coaxial with the axis m, and the outer sealing device 84 is assembled to the seal mounting surface 23.
The outer sealing device 84 includes a metal cored bar and a seal lip made of an elastic body. The core metal is formed into a ring 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 and molded in a high temperature mold, and at the same time, is vulcanized and bonded to the core metal.

Please refer to FIG. A seal mounting 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 sealing device 60 is assembled to the seal mounting surface 24. An inner chamfer 30 is formed on the inner side of the seal mounting surface 24 so that the inner circumference thereof tapers toward the outer ring end surface 63. The inner sealing device 60 will be described later.

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

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 substantially the center in the axial direction. The first inner raceway surface 26 has an arc-shaped cross section in the axial direction, is heat-treated to increase the surface hardness to about 60 HRC, and then is ground.
A shoulder 27 having a large diameter is formed on the outer side of 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, it is connected to the hub flange 86 at an R portion having an arcuate cross section in the axial direction. The large-diameter shoulder 27 and the outer peripheral surface of the R portion are ground, and the lip of the outer side sealing device 84 is in sliding contact therewith.
A small-diameter stepped portion is formed at the inner end of the shaft portion 18, and the inner ring 12 is assembled in an interference fit state.

On the hub flange 86, a plurality of hub bolts 22 are installed at equal intervals in the circumferential direction so as to penetrate in the axial direction. Wheels (not shown) are attached to the outer side surface of the hub flange 86 and fixed by the hub bolts 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 has a second inner raceway surface 28 formed in an annular shape that is coaxial with the axis m at the outer periphery substantially at the center in the axial direction. The second inner raceway surface 28 has an arcuate 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 circumference of the shoulder 29 is a cylindrical surface coaxial with the axis m, and the inner sealing device 60 is assembled to the shoulder 29. An outer chamfer 40 having a tapered diameter toward the inner ring end surface 64 is formed at the inner end of the outer circumference of the shoulder 29.
The inner ring 12 is heat-treated to increase its 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 rollably incorporated between the outer raceway surfaces 16 and 16 and the inner raceway surfaces 26 and 28, which face each other in the radial direction. The balls 21 in each row are arranged by the cage 25 at equal intervals in the circumferential direction. The annular space 83 formed between the outer ring 11 and the inner shaft 20 is filled with grease for lubricating each raceway surface. Thus, the inner shaft 20 is rotatably supported by 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 sealing device 60 includes a seal ring 31 and a slinger 41. FIG. 1 shows a state in which the inner side end of the core metal 32 forming the seal ring 31 and the inner side end of the slinger 41 are assembled by caulking. 2 and 3 are enlarged views of a main part of the seal ring fitting portion and the slinger fitting portion, respectively, showing the forms of the seal ring 31 and the slinger 41 before caulking.

The form of the seal ring 31 will be described with reference to FIGS. 1 and 2.
The seal ring 31 includes a metal cored bar 32 and a plurality of lips 33, 34, 35 made of an elastic body.
The cored bar 32 is formed in an annular shape by press molding a thin cold-rolled steel plate such as SPCC. The cored bar 32 includes a cylindrical fixing portion 36, and an outer end of the fixing portion 36 is bent radially inward at a right angle to form a seal holding portion 37. The outer diameter of the fixed portion 36 is larger than the inner diameter of the seal mounting surface 24. Therefore, when the seal ring 31 is assembled to the outer ring 11, the seal ring 31 is assembled in an interference fit state.

Each lip 33, 34, 35 is formed integrally with the seal holder 37. A grease lip 33 is in contact with the outer circumference of the slinger 41 with a small interference, and prevents the grease enclosed in the annular space 83 from flowing out. A radial lip 34 is in sliding contact with the outer periphery of the slinger 41 to prevent foreign matter from entering the annular space 83 and prevent grease from flowing out of the annular space 83. Reference numeral 35 denotes an axial lip, which is brought into sliding contact with the collar portion 47 of the slinger 41 to prevent foreign matters such as muddy water and dust from directly reaching the radial lip 34.
A rubber material such as nitrile rubber or acrylic rubber is used for the material of each lip 33, 34, 35. Each of the lips 33, 34, 35 is vulcanized and molded by a high temperature mold, and at the same time, is vulcanized and bonded to the seal holding portion 37.

A projecting portion 38 (hereinafter referred to as a "core metal projecting 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.
A sealing portion 39 is uniformly formed on the outer circumference of the cored bar protruding portion 38 over the entire circumference. The sealing portion 39 is made of the same rubber material as the lips 33, 34, 35, is integrally formed with the lips 33, 34, 35 by vulcanization molding, and is vulcanized and adhered to the core metal protruding portion 38. There is. The sealing portion 39 includes a base portion 42 having an outer diameter dimension substantially the same as the outer diameter dimension of the fixing portion 36, and a convex portion 43 protruding outward in the radial direction. The convex portion 43 is formed at the center of the base portion 42 in the axial direction, and the outer diameter dimension thereof is larger than the outer diameter dimension of the fixing portion 36.

The form of the slinger 41 will be described with reference to FIGS. 1 and 3.
The slinger 41 is formed in an annular shape by pressing a stainless steel plate. The slinger 41 has an L-shaped cross section, and has a fixing portion 44 extending in a tubular shape in the axial direction. The fixing portion 44 has a double cylindrical structure that is folded back in the axial direction and is in close contact with the radial direction. The inner peripheral side cylindrical portion 45 (hereinafter referred to as “inner cylindrical portion”) is open to the inner side, and the outer end is connected to the outer peripheral 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 diameter that is smaller than the outer diameter of the shoulder 29. Therefore, when the slinger 41 is assembled to the inner ring 12, the slinger 41 is assembled in an interference fit state.

A projecting portion 48 (hereinafter referred to as a "slinger projecting portion") extending to the inner side is integrally formed at the inner side end portion of the inner cylindrical portion 45 (see FIG. 3). The slinger protrusion 48 is coaxial with the inner cylindrical portion 45 and has a cylindrical shape. The inner diameter dimension of the slinger protrusion 48 is larger than the inner diameter dimension of the inner cylindrical portion 45.
A sealing portion 49 is formed on the inner circumference of the slinger protrusion 48. The sealing portion 49 is made of an elastic material such as nitrile rubber or acrylic rubber, and is attached to the slinger protrusion 48 by vulcanization adhesion. The sealing portion 49 is formed uniformly over the entire inner circumference of the slinger projection 48, and has a base 50 having an inner diameter substantially the same as the inner diameter of the inner cylindrical portion 45, and projects radially inward. And the convex portion 51. The convex portion 51 is formed at the center of the base portion 50 in the axial direction, 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, the form in which the encoder 52 is mounted is shown by a one-dot chain line. The encoder 52 has a disk shape and is coaxially attached to the side surface of the collar 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 of manufacturing the wheel bearing device 10 will be described. The manufacturing method of the present embodiment includes a mounting step 61 for mounting the inner side sealing device 60 and a caulking step 66 for plastically deforming the protrusions 38 and 48. FIG. 4 is an explanatory view illustrating a method of mounting the inner sealing device 60, and shows a state in which the jig 62 is in contact with the cored bar 32 and the slinger 41.

In the mounting step 61, the inner sealing device 60 is mounted on the inner open end of the annular space 83. At this time, the inner side sealing device 60 is arranged coaxially with the annular space 83 with the seal ring 31 facing the opening of the annular space 83 in the assembled state as shown in FIG. 4. Then, the seal ring 31 and the slinger 41 are simultaneously pressed in the axial direction, and the inner sealing device 60 is mounted.

The mounting work is performed using the jig 62. The jig 62 has an A surface and a B surface which are formed in different positions in the axial direction 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 positional displacement amount of the seal ring 31 and the slinger 41 can be set according to the axial positional displacement amount L1 of the A surface and the B surface. As a result, the axial interference between the collar portion 47 and the axial lip 35 can be set to an optimum size.
In this way, the seal ring 31 is press-fitted to the inner circumference of the outer ring 11, and at the same time, the slinger 41 is press-fitted to the outer circumference of the inner ring 12. In the slinger 41, the inner surface of the slinger protrusion 48 may be pressed instead of the flange 47 by appropriately changing the axial position of the surface B.

Next, the state of the fitting portion in the mounting step 61 will be described in more detail with reference to FIGS. 2 and 3.
In the sealing portion 39 of the seal ring 31, the outer diameter dimension of the base portion 42 is equal to the outer diameter dimension of the fixed portion 36. For this reason, the outer circumference of the fixed portion 36 is in strong contact with the inner circumference of the outer ring 11, and the outer circumference of the base portion 42 does not contact the inner circumference of the outer ring 11 or, even when it contacts, the pressing force of the contact surface. Is extremely small. Therefore, the base 42 is not scraped off by the inner circumference 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 core metal protrusion 38 and the outer ring end surface of the outer ring 11 are pressed. 63 becomes flush. In the seal ring 31, the axial length of the cored bar protrusion 38 is substantially equal to the axial length of the inner chamfer 30, so that the cored bar protrusion 38 and the inner chamfer 30 face each other in the radial direction.
The convex portion 43 is formed at a position separated from the position of the minimum diameter of the inner chamfer 30 (indicated by P1 in FIG. 2) toward the outer ring end surface 63 side. On the other hand, the inner chamfer 30 increases in diameter from P1 toward the outer ring end surface 63, so that the convex portion 43 does not contact the inner chamfer 30.
Therefore, in the mounting step 61, the sealing portion 39 of the seal ring 31 is not scraped off by the inner circumference of the outer ring 11. When the seal ring 31 is mounted, the convex portion 43 faces the inner chamfer 30 in the radial direction.

Similarly, the slinger 41 can be mounted on the shoulder 29 of the inner ring 12. This will be described with reference to FIG.
In the sealing portion 49 of the slinger 41, the inner diameter dimension of the base portion 50 is equal to the inner diameter dimension of the inner cylindrical portion 45. Therefore, 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 does not contact the shoulder 29, or even when contacting the shoulder 29, the contact pressure of the contact surface is extremely small. .. Therefore, the base 50 is not scraped off by the shoulder 29.

Further, the slinger 41 is accurately assembled by the jig 62 in the axial position with reference to the seal ring 31 (see FIG. 4). As a result, the slinger protrusion 48 is mounted at a position that faces the outer chamfer 40 in the radial direction.
The convex portion 51 is formed at a position distant from the position of the maximum diameter of the outer chamfer 40 (indicated by P2 in FIG. 3) toward the inner ring end surface 64 side. On the other hand, since the outer chamfer 40 is reduced in diameter toward the inner ring end surface 64, the convex portion 51 does not contact the outer chamfer 40.
Therefore, 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 step 66 will be described. In the present embodiment, the caulking step 66 includes a caulking step 67 (caulking bar caulking step) for caulking the core bar protrusion 38 and a caulking step 68 (slinger caulking step) for caulking the slinger protrusion 48, and each caulking step is performed. 67 and 68 are individually performed.

In the mandrel caulking step 67, the mandrel protrusion 38 is urged toward the inner chamfer 30 in the direction shown by the white arrow G in FIG. As a caulking method, a die (not shown) is pressed against a part of the cored bar protruding portion 38, and the outer ring 11 is rotated while being plastically deformed radially outward, thereby sequentially deforming in the circumferential direction. Alternatively, a caulking method in which a tapered jig (not shown) is pressed to plastically deform the entire cored bar protruding portion 38 radially outward at the same time is appropriately used.

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

Thus, in this embodiment, at the fitting portion between the core metal 32 of the seal ring 31 and the inner circumference of the outer ring 11, the sealing portion 39 can be compressed in the height direction and securely assembled.

On the other hand, in the conventional inner side sealing device 85 as shown in FIG. 6, the seal ring 88 is merely fitted in 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 (the left-right direction in FIG. 6). Therefore, shearing force acts, and the sealing portion 92 is easily damaged. In this way, the sealing portion 92 is scraped off by the outer ring 81. In particular, when the height H3 of the sealing portion 92 is increased, the axial force from the outer ring 81 is more likely to be received, and it becomes more difficult to assemble the seal ring 88. For this reason, in the conventional structure, it is not possible to compress the sealing portion 92 in the radial direction and securely assemble it.

On the other hand, in the present embodiment, the convex portion 43 is assembled by being compressed in the height direction by the inner chamfer 30 and the cored bar protruding portion 38, and the load is applied to the sealing portion 39 in the compression direction. Is working. In general, an elastic body such as rubber has a higher compressive strength than a shear strength, so that the sealing portion 39 is not damaged.
In this way, in this embodiment, the sealing portion 39 formed of the elastic body can be compressed in the height direction and securely assembled. Therefore, it is possible to reliably prevent muddy water or the like from entering the inside of the bearing through the fitting portion between the outer ring 11 and the seal ring 31.

In the slinger crimping step 68, the slinger protrusion 48 is biased toward the outer chamfer 40 in the direction shown 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 metal caulking step 67.
During the crimping process, 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 circumference of the slinger projection 48, a projection 51 projects radially inward over the entire circumference. The convex portion 51 is displaced so as to draw an arc around P2 and approaches the outer chamfer 40.
In this way, the convex portion 51 is compressed by the outer chamfer 40 and the slinger protruding portion 48 in the height direction (direction perpendicular to the slinger protruding portion 48). Since almost no load acts on the protrusion 51 in the shearing direction (direction parallel to the slinger protrusion 48), even if the height H2 of the protrusion 51 is relatively high, it is easy and reliable. Can be assembled to.

In this way, in this embodiment, the sealing portion 49 formed of an elastic body can be compressed in the height direction and securely assembled. Therefore, it is possible to reliably prevent muddy water or the like 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, since the seal holding portion 37 and the flange portion 47 are formed on one side in the axial direction, respectively, the rigidity in the radial direction is greatly different between the inner side and the outer side. Therefore, as shown in FIG. 7, a clearance s is formed in the joint portion with the outer ring 11 or the inner ring 12.
However, in the present embodiment, the cored bar protruding portion 38 and the slinger protruding portion 48 are bent, and the sealing portions 39 and 49 are assembled in a compressed state. The height (corresponding to the heights H1 and H2 of the protrusions 43 and 51) at which the respective sealing portions 39 and 49 project in the radial direction is much larger than the above-mentioned clearance s. Therefore, even if the clearance s exists, each sealing portion can be compressed in the height direction and securely assembled. Therefore, it is possible to reliably prevent muddy water or the like from entering the inside of the bearing through the fitting portion.

Further, in the crimping process of the present embodiment, the respective protruding portions 38 and 48 are plastically deformed along the inner chamfer 30 and the outer chamfer 40, respectively. Therefore, even if the sizes and positions of the chamfers 30 and 40 change due to variations in processing, the sealing portions 39 and 49 can be compressed in the height direction and assembled reliably. Therefore, the muddy water resistance does not change due to variations in the shapes of the chamfers 30 and 40, and it is possible to reliably prevent muddy water or the like from entering the inside of the bearing from the fitting portion.

Further, in the present embodiment, when the inner side sealing device 60 is assembled, the convex portions 43 and 51 are formed at positions apart from P1 or P2. Therefore, the convex portions 43 and 51 do not contact 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, 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 faces the chamfers 30 and 40 in the radial direction, and when the convex portions 43 and 51 are not scraped off, the convex portions 43 and 51 are caulked. , 51 can be compressed in the height direction and securely assembled. Therefore, it is possible to reliably prevent muddy water and the like from entering the inside of the bearing from the joint portion of the core metal 32 and the slinger 41.

Further, in this embodiment, both the seal ring 31 and the slinger 41 are caulked. However, the invention is not limited to this, and only one of them may be caulked.

As described above, according to the assembling method of the present embodiment, when the inner side sealing device 60 is mounted on 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. It is possible to surely incorporate the sealing portion 39 into the fitting portion with 12 without damaging the sealing portion 39. Therefore, it is possible to reliably prevent muddy water and the like from entering the inside of the bearing through the fitting portion. As a result, it is possible to provide a bearing device for a wheel with improved muddy water resistance.

(Embodiment) 10: Wheel bearing device, 11: Outer ring, 12: Inner ring, 14: Flange portion, 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: core metal, 36: fixed Part, 37: seal holding part, 38: core metal protruding part, 39: sealing part, 40: outer chamfer, 41: slinger, 42: base part, 43: convex part, 44: fixed part, 45: inner cylindrical part, 46: outer cylinder part, 47: flange part, 48: slinger protrusion 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: Wheel Bearing Device, 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 bar, 91: Lip, 92: Sealing part, 93: Fixed part, 94: Collar part

Claims (2)

An outer ring having an outer raceway surface on the inner circumference, an inner race having an inner raceway surface on the outer circumference, and a plurality of rolling elements rotatably arranged between the outer raceway surface and the inner raceway surface, Equipped with
The sealing device that closes the inner side 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. Yes, the inner ring has a cylindrical outer peripheral surface on the inner side from the inner raceway surface, and the slinger has a cylindrical fixing portion externally attached to the outer peripheral surface. And
In the inner ring, the inner side end of the outer peripheral surface is formed with an outer chamfer whose diameter decreases toward the end surface,
The slinger integrally has a cylindrical protruding portion that extends coaxially with the fixed portion and extends toward the inner side, and a sealing portion made of an elastic body is integrally formed on the inner periphery of the protruding portion over the entire circumference. Has been done,
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;
And a caulking step of compressing the sealing portion between the protrusion and the outer chamfer by plastically deforming the protrusion along the outer chamfer. An outer ring having an outer raceway surface on the inner circumference, an inner race having an inner raceway surface on the outer circumference, and a plurality of rolling elements rotatably arranged between the outer raceway surface and the inner raceway surface, Equipped with
The sealing device that closes the inner side 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. There is a bearing device for a wheel, wherein the outer ring has a cylindrical inner peripheral surface on the inner side of the outer raceway surface, and the seal ring includes a cylindrical fixing portion internally held on the inner peripheral surface. The manufacturing method of
In the outer ring, an inner chamfer whose diameter increases toward the end surface is formed at the inner side end portion of the inner peripheral surface,
The seal ring integrally has a cylindrical protruding portion that extends coaxially with the fixed portion and extends to the inner side, and a sealing portion made of an elastic body is integrally formed on the outer periphery of the protruding portion over the entire circumference. Has been done,
A mounting step of mounting the sealing device so that at least a part of the sealing portion faces the inner chamfer in a radial direction;
A method for manufacturing a bearing device for a wheel, comprising: a caulking step of compressing the sealing portion between the protrusion and the inner chamfer by plastically deforming the protrusion along the inner chamfer.

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