JP2017106510A5 - - Google Patents

Description

Rolling bearing unit manufacturing method, rolling bearing unit manufacturing apparatus, and vehicle manufacturing method

  The present invention relates to a method for manufacturing a rolling bearing unit used as a wheel bearing rolling bearing unit constituting a wheel driving bearing unit, for example, by combining with a constant velocity joint, and a rolling bearing unit manufacturing apparatus.

  FIG. 14 shows an example of a conventional structure of a wheel driving bearing unit incorporating a wheel supporting rolling bearing unit, which is a type of rolling bearing unit that is an object of the present invention, described in Patent Document 1. Show. The wheel drive bearing unit shown in FIG. 14 is a combination of a wheel support rolling bearing unit 1 and a constant velocity joint outer ring 2. Of these, the wheel support rolling bearing unit 1 includes an outer ring 3, a hub 4, and a plurality of rolling elements (balls in the illustrated example) 5 and 5.

  Of these, the outer ring 3 has a stationary flange 6 on the outer peripheral surface and double row outer ring raceways 7a and 7b on the inner peripheral surface. The hub 4 is formed by combining a hub body 8 and an inner ring 9. Of these, the hub body 8 has a rotation-side flange 10 at a portion near one end of the outer peripheral surface in the axial direction, an inner ring raceway 11a on one axial side in the same axial direction, and a small-diameter step 12 at the other end in the same axial direction. Each has a central hole 13 in the center. In the present specification and claims, unless otherwise specified, “one side” with respect to the axial direction means the outside in the width direction of the vehicle in the state of being assembled to an automobile, and the left side of FIG. 7, 12 is the lower side, and conversely, the right side of FIG. 14 and the upper side of FIGS. say.

  A small-diameter portion 16 through which a flange portion 15 of a bolt 14 that is a coupling member can be inserted through a predetermined guide gap is formed at one end portion in the axial direction of the center hole 13. The inner ring 9 has an inner ring raceway 11b on the outer peripheral surface on the other side in the axial direction, and is externally fitted to the small-diameter step portion 12 of the hub body 8 with an interference fit. Further, a plurality of rolling elements 5, 5 are provided between the outer ring raceways 7a, 7b and the inner ring raceways 11a, 11b so as to be freely rollable in both rows. Further, in this state, of the cylindrical portion 17 provided at the other axial end portion of the hub body 8, the portion protruding from the other axial end opening of the inner ring 9 is caulked by plastic deformation outward in the radial direction. A portion 18 is formed. Then, the other end surface in the axial direction of the inner ring 9 is suppressed by the caulking portion 18 (the coupling force directed to one side in the axial direction with respect to the hub main body 8 is applied to the inner ring 9), whereby each rolling element 5 is provided. 5 has an appropriate preload. A hub-side face spline 19 that is an uneven portion in the circumferential direction is formed on the other end surface in the axial direction of the caulking portion 18 over the entire circumference. In the case of the illustrated example, the tooth tip surface of the hub-side face spline 19 is formed in a planar shape perpendicular to the central axis of the hub body 8.

  The constant velocity joint outer ring 2 includes a cup-shaped mouth portion 20, an end wall portion 21 which is a bottom portion of the mouth portion 20, and a cylinder extending in one axial direction from the center portion of the end wall portion 21. Shaped shaft portion 22. The shaft portion 22 has a cylindrical shape, and an internal thread portion 23 is formed on the inner peripheral surface. In addition, a joint-side face spline 24 that is an uneven portion in the circumferential direction is formed over the entire circumference of the end wall portion 21 near the outer periphery of one end face in the axial direction. In the case of the illustrated example, the tooth tip surface of the joint-side face spline 24 is formed in a planar shape perpendicular to the central axis of the constant velocity joint outer ring 2. The number of teeth on the joint-side face spline 24 is the same as the number of teeth on the hub-side face spline 19.

  Then, the hub body 8 and the joint side face splines 19 and 24 are engaged with each other in a state where the central axes of the hub body 8 and the constant velocity joint outer ring 2 are aligned with each other. The rotational force can be transmitted to and from the outer ring 2 for the constant velocity joint. In this state, the flange portion 15 of the bolt 14 is inserted into the small diameter portion 16 of the center hole 13 of the hub body 8 from one axial direction, and the male screw portion 25 provided at the tip end portion of the flange portion 15 is The outer thread 2 for the constant velocity joint is screwed into the female thread portion 23 and further tightened. Thus, the hub body 8 and the constant velocity joint outer ring 2 are coupled and fixed in a state where the hub main body 8 is sandwiched between the head 26 of the bolt 14 and the constant velocity joint outer ring 2. Yes.

  When the wheel drive bearing unit configured as described above is assembled to a vehicle, the stationary side flange 6 of the outer ring 3 is coupled and fixed to a suspension device, and the wheel (drive wheel) is attached to the rotation side flange 10 of the hub body 8. ) And a brake rotating member such as a disk. Further, a tip end portion of a drive shaft (not shown) that is rotationally driven by the engine via the transmission is spline-engaged with the inside of the constant velocity joint inner ring 27 provided inside the constant velocity joint outer ring 2. When the automobile travels, the rotation of the constant velocity joint inner ring 27 is transmitted to the constant velocity joint outer ring 2 and the hub body 8 via a plurality of balls 28, and the wheels are driven to rotate.

  When assembling the wheel support rolling bearing unit 1 constituting the wheel drive bearing unit configured as described above, first, the outer ring 3 is disposed around the hub body 8, and the outer ring raceways 7a, 7b, between the outer ring raceway 7a on one axial side and the inner ring raceway 11a on one axial side, the rolling elements 5, 5 are provided in a state of being held by a cage 29a on one axial side. Next, the rolling elements 5 and 5 are installed around the inner ring raceway 11b on the other axial side formed on the outer peripheral surface of the inner ring 9 while being held by the cage 29b on the other axial side. Then, the inner ring 9 is externally fitted to the small-diameter step portion 12 formed at the other axial end portion of the hub body 8 with an interference fit. And with such an external fitting operation, the rolling surfaces of the rolling elements 5, 5 (in the other axial row) held by the cage 29 b on the other axial side are set in the axial direction of the outer ring 3. An intermediate assembly (rolling for wheel support before the caulking portion 18 is formed on the cylindrical portion 17 of the hub body 8) is brought into contact with the outer ring raceway 7b on the other axial side formed on the inner peripheral surface near the other end. Bearing unit). Next, the cylindrical portion 17 formed at the other axial end portion of the hub body 8 constituting the intermediate assembly is plastically deformed radially outward to form the caulking portion 18. The inner ring 9 is fixed to the hub body 8 by pressing the other axial end surface of the inner ring 9 in the axial direction by the caulking portion 18. Further, the hub side face spline 19 is then formed on the other axial end surface of the caulking portion 18.

Conventionally, both the caulking portion 18 and the hub-side face spline 19 are formed by swing forging.
Hereinafter, a method for forming the hub-side face spline 19 on the other axial end surface of the caulking portion 18 will be described with reference to FIG. The method for forming the caulking portion 18 is the same as the method for forming the hub-side face spline 19 except that a roll having a different tip end surface shape is used.
As shown in FIG. 15, the hub-side face spline 19 has a predetermined axis with respect to the central axis (the central axis of the wheel-supporting rolling bearing unit 1) α of the hub body 8 at the other axial end surface of the caulking portion 18. It is formed by performing rocking forging using a roll 30 having a central axis β inclined by an angle θ ₁ . In FIG. 15, members other than the hub body 8 (outer ring 3, rolling elements 5, 5, inner ring 9, etc.) are omitted from the members constituting the wheel supporting rolling bearing unit 1. .

  The roll 30 is provided with a processing surface 33 in which convex portions (processing teeth) 31 and 31 and concave portions 32 and 32 are alternately formed over the entire circumference on the front end surface (lower end surface in FIG. 15). ing. With the processed surface 33 of the roll 30 pressed against the other end surface in the axial direction of the caulking portion 18, the roll 30 is rotated about the central axis α of the hub body 8. Here, the roll 30 is supported so as to be rotatable about its own central axis β. Therefore, in a state before the hub-side face spline 19 (uneven portion related to the circumferential direction to be formed) is formed on the other end surface in the axial direction of the caulking portion 18, the roll 30 is moved to the central axis of the hub body 8. When the roll 30 is rotated around α, the roll 30 has its own central axis based on frictional engagement between the tip surfaces of the convex portions 31 and 31 constituting the machining surface 33 and the other axial end surface of the caulking portion 18. Rotates (rotates) around β. On the other hand, after the hub-side face spline 19 is formed to some extent (the tooth-length of the hub-side face spline 19 has increased to some extent), the roll 30 is rotated about the central axis α of the hub body 8. Then, the roll 30 rotates on the basis of the engagement (meshing) between the convex portions 31 and 31 and the concave portions 32 and 32 constituting the processed surface 33 and the hub-side face spline 19. With such a configuration, the hub-side face spline 19 is formed on the other axial end surface of the caulking portion 18 by plastically deforming the other axial end surface of the caulking portion 18. Increase the tooth height and complete the processing.

  By the way, in the case of the method of forming the caulking portion 18 or the hub-side face spline 19 by swing forging as described above, the axial direction of the cylindrical portion 17 (caulking portion 18) and the like while the roll 30 is swinging displaced. In order to press the end portion, the magnitude of the force (the axial force in one axial direction) that restrains the other end surface in the axial direction of the inner ring 9 by the caulking portion 18 varies depending on the circumferential position of the inner ring 9. (Biased).

JP 2009-292422 A

  In view of the circumstances as described above, the present invention provides a rolling bearing unit having a structure in which the other axial end surface of the inner ring constituting the hub is suppressed by a caulking portion formed on the other axial end portion of the hub body. The present invention has been invented to realize a method and an apparatus for manufacturing a rolling bearing unit capable of preventing the axial force that suppresses the inner ring by the caulking portion from being biased in the circumferential direction of the inner ring.

The rolling bearing unit which is the object of the rolling bearing unit manufacturing method according to the first aspect of the present invention and the rolling bearing unit manufacturing apparatus according to the twelfth aspect is provided for an inner ring externally fitted to the hub body. In order to provide a coupling force directed to one side in the axial direction with respect to the hub body, a cylindrical portion provided at the other axial end of the hub body is plastically deformed radially outward, and the caulking portion is The other end surface in the axial direction of the inner ring is held down.

On the other hand, the rolling bearing unit which is the object of the rolling bearing unit manufacturing method according to claim 6 and the rolling bearing unit manufacturing apparatus according to claim 16 is an inner ring externally fitted to the hub body. On the other hand, in order to give a coupling force directed to one side in the axial direction with respect to the hub body, a cylindrical portion provided at the other axial end portion of the hub body is plastically deformed radially outward. The other end surface in the axial direction of the inner ring is held down, and a hub-side face spline that is an uneven portion in the circumferential direction is formed on the other end surface in the axial direction of the caulking portion.
Note that the rolling bearing unit that is the subject of the manufacturing method of the present invention as described above includes, for example, a hub body having an inner ring raceway on one axial side on the outer peripheral surface in the axial direction and an inner ring on the other axial side on the outer peripheral surface. An inner ring that has a track and is externally fitted to a portion near the other axial end of the hub body. And, by pressing the other end surface in the axial direction of the inner ring by a caulking portion formed by plastically deforming a cylindrical portion provided at the other axial end portion of the hub main body radially outward, the hub main body is The inner ring is fixed. Furthermore, an outer ring having a double row outer ring raceway on the inner peripheral surface, and a plurality of rolling elements provided between the outer ring raceway and the inner ring raceways are provided so as to be capable of rolling.

The method for manufacturing a rolling bearing unit according to claim 1, which is intended for a rolling bearing unit having the above-described configuration, uses a molding die having pressing portions at a plurality of locations in the circumferential direction on one side surface in the axial direction. The hub body and the mold are rotated relative to each other at predetermined angles, and the hub body and the mold are rotated relative to each other based on the reciprocating movement of the mold in the axial direction of the hub body. The pressing portion of the mold is pressed against the other axial end of the hub main body in a state where the hub main body and the molding die are rotating relative to each other. The caulking portion is formed by separating the portion from the other axial end portion of the hub body.
It should be noted that either the hub body or the molding die may be index rotated.

On the other hand, the manufacturing method of the rolling bearing unit described in claim 6 intended for the rolling bearing unit having the above-described configuration uses a molding die having pressing portions at a plurality of locations in the circumferential direction on one side surface in the axial direction. The hub body and the mold are relatively rotated relative to each other by a predetermined angle, and the mold is reciprocated in the axial direction of the hub body. In a state where the mold is not relatively rotated, each pressing portion of the mold is pressed against the other end surface in the axial direction of the caulking portion, and the hub main body and the mold are relatively rotated. By separating each pressing portion from the other axial end surface of the caulking portion, a hub-side face spline is formed on the other axial end surface of the caulking portion.
It should be noted that either the hub body or the molding die may be index rotated.

When carrying out the manufacturing method of the rolling bearing unit of the present invention as described above, specifically, the hub main body is moved to the hub body without rotating the mold as in the invention described in claim 9. A structure in which the mold is intermittently rotated by a predetermined angle can be employed.

When carrying out the present invention as described above, specifically, as in the invention described in claim 10 , a configuration having at least two pressing portions can be adopted as the mold. When such a configuration is employed, the pressing portions can be arranged at positions that are rotationally symmetric with respect to the central axis of the mold. In addition, it is preferable to provide each said press part at the circumferential direction equal intervals.
On the other hand, when carrying out the invention described in claim 6 as described above or claims 7 to 10 which directly or indirectly cites this claim 6, the invention described in claim 11 is specifically implemented. Similarly, it is also possible to adopt a configuration in which the molding die has N pressing portions, and each pressing portion is disposed at a position that is not rotationally symmetric with respect to the central axis of the molding die. When such a configuration is adopted, the number of concave portions of the concave and convex portions constituting the hub-side face spline is M, and one side surface in the axial direction of the mold is divided into M sections (fans) in the circumferential direction. When divided into mold sections, it is possible to adopt a configuration in which the respective pressing portions are formed in N sections that are closest to the equidistant arrangement in the circumferential direction of the molding die selected from the sections. In this case, preferably, each of the pressing portions is formed so that the center position in the circumferential direction of each pressing portion matches the center position in the circumferential direction of each section.
The rotational symmetry is a property in which when m is an integer of 2 or more and a certain positional relationship is rotated (360 / m) ° about a certain axis, the same positional relationship as before rotation is obtained. (Such a positional relationship is referred to as an m-fold symmetrical positional relationship). For example, the positional relationship of m places at equal intervals in the circumferential direction on the circumference centered on a certain axis is a positional relationship of m-fold symmetry. That is, the positional relationship that is rotationally symmetric about the central axis of the hub main body includes a case where the respective pressing portions are in a positional relationship other than equal intervals in the circumferential direction.
Further, for example, in the case of the invention described in claim 6 and claim 16 , the number and arrangement of the pressing portions are appropriately determined in relation to the number of teeth of the hub-side face spline formed in the caulking portion. . For example, depending on the relationship between the number of teeth of the face spline and the number of the pressing portions, it may not be possible to arrange them in a positional relationship that is equally spaced in the circumferential direction or a positional relationship that is rotationally symmetric. In such a case, based on the relationship between the number of teeth of the hub-side face spline and the number of the pressing portions, the respective pressing portions are positioned in a circumferential relationship at equal intervals as much as possible, or the rotational symmetry. It is preferable to arrange in a positional relationship close to the positional relationship.

A rolling bearing unit manufacturing apparatus according to claim 12 for the rolling bearing unit having the above-described configuration includes a forming die, an oscillation mechanism, and an index rotating mechanism.
Of these, the mold has pressing portions at a plurality of locations in the circumferential direction on one side surface in the axial direction.
The oscillation mechanism is for reciprocating the mold in the axial direction of the hub body.
The index rotating mechanism is for intermittently rotating the hub body and the mold intermittently by a predetermined angle. In addition, the object which the index rotation mechanism is rotationally driven may be either the hub body or the mold.
In addition, the index rotation mechanism intermittently relatively rotates the hub body and the mold by a predetermined angle, and the oscillation mechanism reciprocates the mold in the axial direction of the hub body. Based on this, in a state where the hub main body and the mold are not relatively rotated, the pressing portion of the mold is pressed against the other axial end of the hub main body, and the hub main body and the mold In a state in which the mold is relatively rotated, each pressing portion of the mold has a function of separating from the other axial end portion of the hub body.

A rolling bearing unit manufacturing apparatus according to claim 16 intended for a rolling bearing unit having the above-described configuration includes a forming die, an oscillation mechanism, and an index rotating mechanism.
Of these, the mold has pressing portions at a plurality of locations in the circumferential direction on one side surface in the axial direction.
The oscillation mechanism is for reciprocating the mold in the axial direction of the hub body.
The index rotating mechanism is for intermittently rotating the hub body and the mold intermittently by a predetermined angle.
In addition, the index rotation mechanism intermittently relatively rotates the hub body and the mold by a predetermined angle, and the oscillation mechanism reciprocates the mold in the axial direction of the hub body. Based on this, in a state where the hub main body and the mold are not relatively rotated, each pressing portion of the mold is pressed against the other end surface in the axial direction of the caulking portion, and the hub main body and the mold In a state where the mold is relatively rotated, each pressing portion of the mold has a function of separating from the other end surface in the axial direction of the caulking portion.

When carrying out the invention described in any one of claims 12 to 18 as described above, specifically, as in the invention described in claim 19 , the index rotation mechanism is configured to replace the mold. A configuration in which the hub body is intermittently rotated by a predetermined angle without being rotated can be employed.

According to the rolling bearing unit manufacturing method and the rolling bearing unit manufacturing apparatus of the present invention configured as described above, the other axial end surface of the inner ring constituting the hub is formed at the other axial end portion of the hub body. In the rolling bearing unit having a structure to be suppressed by the caulking portion, the axial force applied from the caulking portion to the inner ring can be prevented from being biased with respect to the circumferential direction of the inner ring.
That is, in the method of manufacturing a rolling bearing unit according to the present invention, the mold and the hub body are intermittently relatively rotated by a predetermined angle, and the mold is reciprocated in the axial direction of the hub body. Let Then, in a state where the molding die and the hub main body are not relatively rotated, the plurality of pressing portions constituting the molding die are not swung around the central axis of the hub main body. The caulking portion or the hub-side face spline is formed by simultaneously pressing the other end portion in the axial direction of the hub body. For this reason, when forming the caulking portion or the hub-side face spline, it is possible to prevent an uneven load from being applied to the caulking portion (or at least smaller than the case of the swing forging described above), It is possible to prevent the axial force applied to the inner ring from the caulking portion from being biased in the circumferential direction of the inner ring (it can be difficult to bias).

The schematic diagram for demonstrating the structure of the manufacturing apparatus of the rolling bearing unit of the 1st example of embodiment of this invention. FIG. 2 is an enlarged partial cross-sectional view corresponding to part A in FIG. 1. Similarly, the perspective view which takes out and shows only a shaping | molding die. The center angle of one of the processing teeth formed on the mold shows the relationship between the reciprocal number N of the ratio of tightening in the circumferential direction of the mold and the hoop stress generated on the outer peripheral surface of the inner ring. Diagram. A partial cross-sectional view (A) showing a state in which the machining teeth of the mold are pressed against the cylindrical portion of the hub body by the oscillation mechanism, and the machining teeth of the molding die by the oscillation mechanism. Partial cross-sectional view (B) which shows the state currently separated from. The diagram for demonstrating operation | movement of an oscillation mechanism and a shaft feed mechanism. The figure similar to FIG. 2 which shows the 2nd example of embodiment of this invention. Similarly, the perspective view which takes out and shows only the shaping | molding die for face splines. Similarly, the schematic diagram for demonstrating one example of arrangement | positioning of the processing tooth of the shaping | molding die for face splines. Similarly, the schematic diagram for demonstrating a mode that a face spline is formed. Similarly, the diagram for demonstrating operation | movement of a stroke adjustment mechanism. The figure similar to FIG. 2 which shows the 3rd example of embodiment of this invention. Similarly, when forming a hub side face spline, a schematic diagram for explaining conditions for changing the stroke of the oscillation mechanism. Sectional drawing which shows an example of the conventional structure of the wheel drive bearing unit incorporating the wheel support bearing unit which is 1 type of the rolling bearing used as the object of this invention. Sectional drawing which shows one example of the manufacturing method of the conventional wheel drive bearing unit.

[First example of embodiment]
A first example of an embodiment of the present invention will be described with reference to FIGS. The present invention is characterized by a method of forming the caulking portion and a hub-side face spline in the caulking portion so that the axial force for restraining the inner ring by the caulking portion does not deviate with respect to the circumferential direction of the inner ring. It is in the point which devised the method of forming. In particular, the feature of this example is the method of forming the caulking portion and the structure of a manufacturing apparatus (pressing apparatus) used for forming the caulking portion. It should be noted that conventional procedures for manufacturing each member constituting a wheel bearing rolling bearing unit by subjecting a metal material to plastic processing such as forging processing, finishing processing such as turning, and finishing processing such as polishing, etc. Since it is the same as the manufacturing method of the rolling bearing unit widely known from the above, the description is omitted.

  The rolling bearing unit that is the object of the rolling bearing unit manufacturing method and the rolling bearing unit manufacturing apparatus of this example is the wheel supporting rolling bearing unit 1 (see FIG. 14) and the constant velocity joint, as in the conventional structure described above. The outer ring 2 is used in combination. Of these, the wheel support rolling bearing unit 1 includes an outer ring 3, a hub 4, and a plurality of rolling elements (balls in the illustrated example) 5 and 5.

  Of these, the outer ring 3 has a stationary flange 6 on the outer peripheral surface and double row outer ring raceways 7a and 7b on the inner peripheral surface. The hub 4 is formed by combining a hub body 8 and an inner ring 9. Of these, the hub body 8 has a rotation-side flange 10 at a portion near one end of the outer peripheral surface in the axial direction, an inner ring raceway 11a on one axial side in the same axial direction, and a small-diameter step 12 at the other end in the same axial direction. Each has a central hole 13 in the center.

  A small-diameter portion 16 through which a flange portion 15 of a bolt 14 that is a coupling member can be inserted through a predetermined guide gap is formed at one end portion in the axial direction of the center hole 13. The inner ring 9 has an inner ring raceway 11b on the outer peripheral surface on the other side in the axial direction, and is externally fitted to the small-diameter step portion 12 of the hub body 8 with an interference fit. Further, a plurality of rolling elements 5, 5 are provided between the outer ring raceways 7a, 7b and the inner ring raceways 11a, 11b so as to be freely rollable in both rows. Further, in this state, of the cylindrical portion 17 provided at the other axial end portion of the hub body 8, the portion protruding from the other axial end opening of the inner ring 9 is caulked by plastic deformation outward in the radial direction. A portion 18 is formed. Further, by pressing the other end surface in the axial direction of the inner ring 9 by the caulking portion 18, an appropriate preload is applied to the rolling elements 5 and 5. A hub-side face spline 19 that is an uneven portion in the circumferential direction is formed on the other end surface in the axial direction of the caulking portion 18 over the entire circumference. In the case of the illustrated example, the tooth tip surface of the hub-side face spline 19 is formed in a planar shape perpendicular to the central axis of the hub body 8.

  The constant velocity joint outer ring 2 includes a cup-shaped mouth portion 20, an end wall portion 21 which is a bottom portion of the mouth portion 20, and a cylinder extending in one axial direction from the center portion of the end wall portion 21. Shaped shaft portion 22. The shaft portion 22 has a cylindrical shape, and an internal thread portion 23 is formed on the inner peripheral surface. In addition, a joint-side face spline 24 that is an uneven portion in the circumferential direction is formed over the entire circumference of the end wall portion 21 near the outer periphery of one end face in the axial direction. In the case of the illustrated example, the tooth tip surface of the joint-side face spline 24 is formed in a planar shape perpendicular to the central axis of the constant velocity joint outer ring 2. The number of teeth on the joint-side face spline 24 is the same as the number of teeth on the hub-side face spline 19.

  Then, the hub body 8 and the joint side face splines 19 and 24 are engaged with each other in a state where the central axes of the hub body 8 and the constant velocity joint outer ring 2 are aligned with each other. The rotational force can be transmitted to and from the outer ring 2 for the constant velocity joint. In this state, the flange portion 15 of the bolt 14 is inserted into the small diameter portion 16 of the center hole 13 of the hub body 8 from one axial direction, and the male screw portion 25 provided at the tip end portion of the flange portion 15 is The outer thread 2 for the constant velocity joint is screwed into the female thread portion 23 and further tightened. Thus, the hub body 8 and the constant velocity joint outer ring 2 are coupled and fixed in a state where the hub main body 8 is sandwiched between the head 26 of the bolt 14 and the constant velocity joint outer ring 2. Yes.

Next, the structure of the manufacturing apparatus (caulking press apparatus 34) of this example for forming the caulking portion 18 will be described.
The caulking press device 34 includes a pedestal 35, an apparatus main body 36, an oscillation mechanism 37, a caulking mold 38, an index mechanism 39, and an axis feed mechanism.
Among these, the apparatus main body 36 has a column part 40 having a substantially truncated cone shape and a support part 41.
Among these, the column part 40 has its lower end fixed to one half (the right half in FIG. 1) of the upper surface of the pedestal 35.
The support portion 41 is provided in a state of projecting in a horizontal direction from a part of the peripheral surface near the upper end of the column portion 40.

The oscillation mechanism 37 has a drive cylinder 42 and a gripping tool 43.
Of these, the drive cylinder 42 is constituted by an electric cylinder or a hydraulic cylinder, and is supported by one end portion (left end portion in FIG. 1) of the support portion 41 of the apparatus main body 36.
The gripping tool 43 is for fixing (gripping) the caulking mold 38 and is fixed to the lower end of the drive cylinder 42.
The caulking mold 38 gripped by the gripper 43 by the oscillation mechanism 37 is moved in the vertical direction (the vertical direction in FIGS. 1 and 2 and the direction of the central axis of the hub body 8 during processing). ) In a predetermined frequency (for example, 50 to 200 Hz) (periodically), while the caulking mold 38 is moved at a predetermined speed (for example, 1 to 5 mm / sec) by pressing toward the hub main body 8 (downward) to press against the other axial end of the hub main body 8 with a predetermined load {eg, 49 to 196 kN (5 to 20 tf)}. . The stroke (downward displacement) of the caulking mold 38 by the shaft feed mechanism is, for example, 5 to 15 mm. The vertical direction in FIGS. 1 and 2 does not necessarily coincide with the vertical direction in use. When the electric drive cylinder 42 is employed, a configuration in which the drive cylinder 42 is driven by a servo motor can be employed.

The caulking mold 38 is a member corresponding to the mold described in the claims, and includes a main body portion 44, a gripped portion 45, a plurality of (four in this example) processing teeth 46, 46.
Of these, the main body 44 is formed in a state in which it protrudes from the center of the cylindrical large-diameter portion 47 and one axial end surface (the lower end surface in FIGS. 2 and 3) of the large-diameter portion 47 to one axial side. And a cylindrical small-diameter portion 48. Further, at four positions at equal intervals in the circumferential direction on one end surface in the axial direction of the main body portion 44 (one end surface in the axial direction of the small diameter portion 48 and one end surface in the axial direction of the large diameter portion 47), Engaging grooves 49, 49 are formed radially on the outer circumferential edge (from the central portion of the one end surface in the axial direction of the small-diameter portion 48 to the radially outer end edge of the one end surface in the axial direction of the large-diameter portion 47). Is formed. That is, the engaging grooves 49, 49 are arranged in a positional relationship that is 90 ° apart from each other at the central angle.
Each of the engaging grooves 49, 49 is formed in a fan shape whose shape viewed from the axial direction increases in the width dimension in the circumferential direction as it goes outward in the radial direction. However, in consideration of the ease of processing, the shape of each engaging concave groove viewed from the axial direction may be rectangular. Even when such a configuration is adopted, the respective engaging grooves are formed radially on one end face in the axial direction of the main body 44.
The gripped portion 45 has a cylindrical shape, and is formed on the other end surface in the axial direction of the large diameter portion 47 so as to protrude in the other axial direction.

Each of the processed teeth 46, 46 is a member corresponding to the pressing portion described in the claims, and in the state assembled to the main body 44, the shape viewed from the axial direction is the main body 44. The width of the main body 44 in the circumferential direction increases toward the outer side in the radial direction. In addition, the machining teeth 46 and 46 are caulked recesses 50 on one end face (the lower end face in FIGS. 2, 3, and 5) in the axial direction of the main body 44 in the state of being assembled to the main body 44. Is formed. Each of the processing teeth 46, 46 having such a configuration is assembled to the main body 44 in the other half of the main body 44 in the axial direction (the upper half of FIGS. 2, 3 and 5). ) Is press-fitted into the respective engaging grooves 49, 49 of the main body 44. Further, in this state, of the processing teeth 46 and 46, the inner half portion in the radial direction of the main body 44 (in the part formed in the small diameter portion 48 of the engagement grooves 49 and 49). One end surface in the axial direction of the press-fitted portion) is located on the same plane (or substantially on the same surface) as the one end surface in the axial direction of the small diameter portion 48. On the other hand, in the state assembled to the main body 44, the outer half of the processing teeth 46, 46 in the radial direction of the main body 44 (of the engagement grooves 49, 49, the The axial half piece (the lower half of FIGS. 1, 2, and 5) of the portion that is press-fitted into the portion formed radially outward from the radially outer edge of the small-diameter portion 48 is the large diameter It protrudes from the axial direction one end surface of the part 47 to the axial direction one side. That is, the processing teeth 46 are provided at four positions at equal intervals in the circumferential direction of the main body 44. In other words, the respective processing teeth 46 are arranged in a positional relationship that is 90 ° apart from each other at the central angle.
The caulking mold 38 having such a configuration is assembled in a state where the gripped portion 45 is gripped by the gripping tool 43 of the oscillation mechanism 37.

The index mechanism 39 includes an index driving unit 52 and an index table 51.
Of these, the index driving unit 52 is for index rotation of the index table 51 at a predetermined angle θ ₂ (intermittent rotation by a predetermined angle θ ₂ ). Such an index driving unit 52 is fixed to the other half (the left half in FIG. 1) of the upper surface of the pedestal 35. The predetermined angle θ ₂ is set to be equal to or smaller than the central angle θ ₃ of one of the processing teeth 46, 46 (θ ₂ ≦ θ ₃ ). The index driving unit 52 may employ a configuration in which a Geneva mechanism or a cam index mechanism is driven by an index type direct drive motor (DD motor) or a servo motor, for example. In addition, since the structure of a Geneva mechanism and a cam index mechanism can employ | adopt various structures known conventionally, detailed description is abbreviate | omitted.
The index table 51 is provided on the upper side of the index driving unit 52. Such an index table 51 can fix the hub body 8 on the upper surface without rattling, with the central axis of the hub body 8 aligned with the vertical direction in FIGS.

  In the case where the index driving unit 52 constituting the index mechanism 39 is driven by a servo motor, the index driving unit 52 and the drive cylinder 42 of the oscillation mechanism 37 are shared (one It is also possible to adopt a configuration driven by a servo motor. When such a configuration is employed, for example, a configuration in which the operation of the index mechanism 39 and the operation of the oscillation mechanism 37 are synchronized by incorporating a mechanical synchronization mechanism can be employed. However, it is possible to adopt a configuration in which the operation of the index mechanism 39 and the operation of the oscillation mechanism 37 are controlled separately.

The shaft feed mechanism (not shown) is incorporated in the apparatus main body 36. In such a shaft feed mechanism, the caulking mold 38 is directed toward the hub body 8 fixed to the index table 51 at a predetermined interval and at a predetermined speed during processing. For displacement in the direction. Specifically, the axial feed mechanism starts processing, and the processing teeth 46 and 46 of the caulking mold 38 have the same amount around the entire circumference of the other axial end surface of the cylindrical portion 17 of the hub body 8. Until it is pressed only (until the other end surface in the axial direction is pressed by one turn), only the force that supports the reaction force of the pressing is applied to the caulking mold 38. The mold 38 is not displaced in the axial direction. That is, in the range indicated by X in FIG. 6, the reference height (the height in the state where the caulking mold 38 is the highest in the stroke of the oscillation (reciprocating motion) by the oscillation mechanism 37 ) is h _1. In this state, only a force that supports the reaction force of the pressing is applied.
On the other hand, when each of the processing teeth 46, 46 of the caulking mold 38 presses the entire circumference of the other axial end surface of the cylindrical portion 17 of the hub body 8 by the same amount {as indicated by Y in FIG. In the case of this example, when the hub body 8 has been index-rotated 8 times, in other words, the hub body 8 and the center of each processing tooth 46, 46 are the centers of the adjacent processing teeth 46, 46. At the time of relative rotation by an angle (90 ° in this example), the caulking mold 38 is directed toward the hub body 8 in order to change the reference height to h ₂ (the caulking mold). The amount by which the mold 38 presses the cylindrical portion 17 is displaced by h ₁ −h ₂ ). The shaft feed mechanism repeatedly performs the above-described operation. In FIG. 6, for convenience of description, the shaft feed mechanism is operated when the index is rotated three times. However, in the case of the structure of this example, the shaft feed mechanism is operated when the index is rotated eight times. .
Also, the speed V at which the axis feed mechanism for displacing the caulking mold 38, the reference height of the caulking mold 38 at the start of machining and h _a reference of the caulking mold 38 during processing ends the height and _{h b,} the time at the start of machining and _{t a,} in the case where the processing at the end of time was _{t b,} as defined in _{(h a -h b) / (} t b -t a). In the case shown in FIG. 6, the speed V at which the shaft feeding mechanism displaces the caulking mold 38 is (h ₁ −h ₃ ) / (t ₂ −t ₁ ).
The shaft feed mechanism having the above-described configuration is a hydraulic or mechanical mechanism, and is configured by a mechanism different from the oscillation mechanism 37.

Next, a method for forming the caulking portion 18 using the caulking press device 34 of the present example having the above-described configuration will be described.
When the caulking portion 18 is formed using the caulking press device 34, an intermediate assembly (a wheel support rolling bearing unit before the caulking portion 18 is formed in the cylindrical portion 17 of the hub body 8) is used. In a state where the central axis of the hub main body 8 is aligned with the vertical direction of FIGS. 1 and 2 (the one axial end of the hub main body 8 is directed downward and the other axial end is directed upward), The hub body 8 is fixed to the index table 51. The vertical direction in FIGS. 1 and 2 does not necessarily coincide with the vertical direction in use.

  Next, the oscillation mechanism 37 is operated to cause the caulking mold 38 to reciprocate at a predetermined frequency (periodically) in the vertical direction of FIGS. In the case of this example, the caulking mold 38 does not swing, rotate about its own central axis, or displace in the horizontal direction. That is, the caulking mold 38 periodically reciprocates only in the vertical direction of FIGS. 1 and 2 (the direction of the central axis of the hub body 8).

At the same time, the is indexed rotating the hub body 8 by actuating the indexing mechanism 39 is fixed to the index table 51 at a predetermined angle theta _2. In this example, it has a the predetermined angle theta ₂ and 12 °. Note that there is no particular relationship between the timing of starting the operation of the oscillation mechanism 37 and the timing of starting the operation of the index mechanism 39. In the case of adopting a configuration in which the index drive unit 52 constituting the index mechanism 39 and the drive cylinder 42 constituting the oscillation mechanism 37 are driven by a common servo motor, the oscillation mechanism 37 and the index The mechanism 39 starts operating simultaneously. In this case, when a mechanism for synchronizing the operation of the index mechanism 39 and the operation of the oscillation mechanism 37 is incorporated, the oscillation mechanism 37 and the index mechanism 39 are in a synchronized state. Start operation.
The oscillation stroke by the oscillation mechanism 37 is appropriately determined in consideration of the material and shape of the hub main body 8 to be processed.

Then, in the state where the oscillation mechanism 37 and the index mechanism 39 are operated as described above, the machining teeth 46 and 46 of the caulking mold 38 are connected to the other axial end surface of the cylindrical portion 17 of the hub body 8. To form the caulking portion 18. As described above, the shaft feeding mechanism is configured to displace the caulking mold 38 toward the hub main body 8 at a predetermined speed step by step. Specifically, the axial feed mechanism moves the caulking mold 38 at the time when the other end surface in the axial direction of the cylindrical portion 17 is pressed by the same amount over the entire circumference by the processing teeth 46, 46. It is displaced toward the hub body 8. In other words, every time the hub body 8 and each of the processing teeth 46, 46 rotate relative to each other by a central angle (90 °) between the adjacent processing teeth 46, 46, the caulking mold 38. Is displaced toward the hub body 8. In other words, in the case of this example, the caulking mold 38 is displaced toward the hub body 8 every time the hub body 8 rotates eight times as an index.
Hereinafter, the operation of the shaft feed mechanism will be described with reference to FIG. 6 shows, for convenience of notation, but by operating the axis feed mechanism when the three indices rotated, in the case of the construction of this embodiment, the axis feed mechanism at the time of the indexed rotating 8 times Make it work.
First, in the range shown by X in FIG. 6, the reference height (height of the highest state the crimping mold 38 of the stroke of the oscillation by the oscillation mechanism 37) while the h ₁ Only the force that supports the reaction force of the pressing is applied. On the other hand, when each of the processing teeth 46, 46 of the caulking mold 38 presses the entire circumference of the other axial end surface of the cylindrical portion 17 of the hub body 8 by the same amount {as indicated by Y in FIG. In the case of this example, when the hub main body 8 has been index-rotated 8 times}, the caulking mold 38 is directed toward the hub main body 8 in order to change the reference height to h _2. It is displaced by (the amount by which the caulking mold 38 presses the cylindrical portion 17 and h ₁ −h ₂ ).
Further, the amount by which the caulking mold 38 is displaced by such a shaft feed mechanism is determined in relation to the amount by which the respective machining teeth 46 and 46 press the cylindrical portion 17.

Specifically, as shown in FIG. 5 (A), the caulking mold 38 is displaced downward by the oscillation mechanism 37 at a timing when the hub body 8 is not rotated. The caulking concave portions 50, 50 of the processing teeth 46, 46 are pressed against the other end surface in the axial direction of the cylindrical portion 17. In other words, the caulking molding die 38 is displaced downward by the oscillation mechanism 37 so that the caulking concave portions 50, 50 of the respective processing teeth 46, 46 are moved in the axial direction of the cylindrical portion 17, etc. In a state where the hub body 8 is pressed against the end face, the hub body 8 is not index rotated. At this time, the caulking concave portions 50 and 50 of all the processing teeth 46 and 46 simultaneously press the other axial end surface of the cylindrical portion 17. Therefore, the caulking concave portions 50, 50 of the respective processing teeth 46, 46 press the other end surface in the axial direction of the cylindrical portion 17, and the other end surface in the axial direction of the cylindrical portion 17 is circumferential. The four positions are simultaneously pressed (plastically deformed).
On the other hand, as shown in FIG. 5 (B), at the timing when the hub body 8 is rotating, the caulking mold 38 is displaced upward by the oscillation mechanism 37, and the caulking mold 38 is moved. The processing teeth 46 are separated from the other axial end surface of the cylindrical portion 17. In other words, the caulking mold 38 is displaced upward by the oscillation mechanism 37, and the machining teeth 46, 46 of the caulking mold 38 are moved to the other axial end surface of the cylindrical portion 17. The hub body 8 is rotated by an index while being separated from the hub body 8.

  As described above, in the case of this example, the hub body 8 and the processing teeth 46, 46 are relatively rotated by the central angle (90 °) between the adjacent processing teeth 46, 46, When the other end surface in the axial direction of the cylindrical portion 17 is pressed by the same amount over the entire circumference by each processing tooth 46, 46, the caulking molding is performed by the shaft feeding mechanism. The mold 38 is displaced toward the hub body 8. In other words, the caulking mold 38 is displaced toward the hub main body 8 by the shaft feed mechanism when the hub main body 8 is index-rotated eight times. In this way, the distance between the other axial end surface of the cylindrical portion 17 and the caulking concave portions 50, 50 of the respective processing teeth 46, 46 of the caulking mold 38 can be kept within a predetermined range.

By repeating the above operation, the other end surface in the axial direction of the cylindrical portion 17 is plastically deformed outward in the radial direction over the entire circumference to form the caulking portion 18. The processing end timing can be determined based on, for example, the time from the start of processing or the magnitude of the axial force applied by the caulking portion 18 to the inner ring 9. In the case of this embodiment, the hub body 8, because of the predetermined angle theta ₂ at the time of index rotation 12 °, the said hub body 8 is eight times indexed rotation, the other axial end surface of the cylindrical portion 17 , And are pressed over the entire circumference by the processing teeth 46, 46.

According to the rolling bearing unit manufacturing method and rolling bearing unit manufacturing apparatus (the caulking press apparatus 34) of the present example having the above-described configuration, the other axial end surface of the inner ring 9 constituting the hub 4 is In the rolling bearing unit having a structure to be suppressed by the caulking portion 18, the axial force applied from the caulking portion 18 to the inner ring 9 can be prevented from being biased with respect to the circumferential direction of the inner ring 9.
That is, in the manufacturing method of the rolling bearing unit of the present example, the hub body 8 is rotated and the caulking mold 38 is reciprocated in the axial direction of the hub body 8. Then, in a state where the hub body 8 is not rotating, the caulking mold 38 is displaced only in the axial direction without swinging, and all the processing of the caulking mold 38 is performed. The caulking portion 18 is formed by simultaneously pressing the caulking concave portions 50 of the teeth 46 and 46 against the other axial end portion of the hub body 8. For this reason, when the caulking portion 18 is formed, the other end portion in the axial direction of the hub main body 8 is simultaneously positioned at four circumferentially equidistant positions by the processing teeth 46 and 46 toward the one side in the axial direction. Pressed. As a result, it is possible to prevent an offset load from being applied to the caulking portion 18 so that the axial force applied from the caulking portion 18 to the inner ring 9 is not biased with respect to the circumferential direction of the inner ring 9.

In the case of the caulking press device 34 of this example, the number of each of the processing teeth 46, 46 of the caulking mold 38 is four. Further, the ratio at which the central angle θ ₃ (θ ₃ = 12 °) of one of the processing teeth 46, 46 is tightened in the circumferential direction (360 °) of the caulking mold 38. 1/30, and the reciprocal N of the ratio is 30. FIG. 4 shows the relationship between the reciprocal number N and the hoop stress generated on the outer peripheral surface of the inner ring 9 (the tensile stress in the circumferential direction generated on the outer peripheral surface of the inner ring 9). As is clear from FIG. 4, the hoop stress decreases as the reciprocal number N increases. However, if the reciprocal number N is excessively increased, the circumferential width (center angle θ ₃ ) of each of the processing teeth 46 and 46 becomes small, and the strength of each of the processing teeth 46 and 46 becomes insufficient. There is a possibility that the processing cost of the teeth 46 and 46 increases or the processing time becomes long. For this reason, for example, when the outer diameter of the caulking portion 18 is 35 mm to 40 mm, the reciprocal number N is set to about 25 to 35 (preferably N = 30).
Further, if the number of processed teeth of the mold is excessively increased, the processing load may increase or the hoop stress may increase due to the influence of adjacent processed teeth. For this reason, the number of processed teeth is preferably 2 to 8.

[Second Example of Embodiment]
A second example of the embodiment of the present invention will be described with reference to FIGS. The rolling bearing unit manufacturing apparatus (face spline pressing device 54) of this example is for forming the hub side face spline 19 which is an uneven portion in the circumferential direction on the other end surface in the axial direction of the caulking portion 18. The face spline mold 55 is different from the structure of the caulking mold 38 of the first example of the embodiment described above. Further, the face spline press device 54 of this example does not include the shaft feed mechanism provided in the caulking press device 34 of the first example of the above-described embodiment. Instead, the face spline press device 54 of this example has a stroke adjustment mechanism for the oscillation mechanism to adjust the stroke of the oscillation (reciprocal amplitude) during processing. Hereinafter, the structure of the face spline mold 55 will be described.

The face spline mold 55 has a plurality of main body portions 44a, gripped portions 45a, and a plurality (four in this example), like the caulking mold 38 of the first example of the embodiment described above. It has processing teeth 46a and 46a.
Of these, the main body 44a is formed in a state in which it protrudes from the center of the columnar large-diameter portion 47a and one axial end surface (the lower end surface in FIGS. 7 and 8) of the large-diameter portion 47a to one axial side. And a cylindrical small-diameter portion 48a. Further, of the one axial end surface of the main body 44a, the axial end surface of the large diameter portion 47a is located at four positions that are substantially equally spaced in the circumferential direction of the axial end surface of the large diameter portion 47a. An engaging groove 49a that radiates from the radially inner end edge (the radially outer end edge of the other end surface in the axial direction of the small diameter portion 48a) to the radially outer end edge of the one end surface in the axial direction of the large diameter portion 47. 49a are formed. Each of the engaging concave grooves 49a and 49a is formed in a fan shape in which the shape seen from the axial direction increases in width in the circumferential direction as it goes outward in the radial direction. However, in consideration of the ease of processing, the shape of each engaging concave groove viewed from the axial direction may be rectangular. Even when such a configuration is adopted, the respective engaging grooves are formed radially on one end face in the axial direction of the main body 44a.

The gripped portion 45a has a cylindrical shape, and is formed in a state of protruding to the other axial direction on the other axial end surface of the large diameter portion 47a.
Each of the processed teeth 46a and 46a is assembled in the main body portion 44a, and the circumferential direction of the main body portion 44a is such that the shape seen from the axial direction is outward in the radial direction of the main body portion 44a. Is formed in a substantially triangular shape with a large width dimension. Further, each of the processed teeth 46a, 46a has a face spline forming portion 53 on one end surface (the lower end surface in FIGS. 7 and 8) in the axial direction of the main body portion 44a in a state assembled to the main body portion 44a. Is formed. Each of the processing teeth 46a, 46a having such a configuration is configured so that the other half portion (the upper half portion in FIGS. 7 and 8) of the main body portion 44a in the axial direction is assembled in the main body portion 44a. The main body 44a is press-fitted into the engaging grooves 49a and 49a. Further, in this state, the axial half piece (the lower half part of FIGS. 7 and 8) of each of the processing teeth 46a and 46a protrudes to the axial one side from the axial end face of the large diameter portion 47a. Yes.
The face spline mold 55 having such a configuration is assembled in a state where the gripped portion 45a is gripped by the gripping tool 43 (see FIG. 1) of the oscillation mechanism 37.

In the case of this example, the number of teeth (the number of concave portions and the number of convex portions) of the hub-side face spline 19 formed in the caulking portion 18 is 31. Further, each of the forming teeth 46a In accordance with this, the central angle theta ₃ of the one forming teeth 46a of 46a, is set to 360/31 ≒ 11.6 °. Further, the number of each of the processing teeth 46a and 46a is four. Therefore, in the case of this example, the processing teeth 46a and 46a (the engagement grooves 49a and 49a) are arranged at four positions at equal intervals in the circumferential direction of the main body 44a (hub main body 8). I can't do it. The reason for this is that the grooves of the hub-side face spline 19 having 31 teeth do not exist at evenly spaced positions with a 90 ° pitch. For this reason, in the case of this example, the respective processing teeth 46a, 46a (the respective engaging concave grooves 49a, 49a) are set as much as possible in consideration of the circumferential position of the groove of the hub-side face spline 19 as much as possible. It arrange | positions in the state close | similar to the positional relationship of equal distribution regarding the circumferential direction of.

An example of a method for determining the arrangement of the processing teeth 46a and 46a will be described with reference to FIG. FIG. 9 shows an axial piece of the main body portion 44a of the face spline mold 55 when the number of concave portions of the concave and convex portions constituting the hub side face spline 19 is M (31 in this example). The schematic diagram which divided | segmented the end surface into M (31) divisions equally spaced with respect to the circumferential direction is shown. From such sections, for example, four sections (the number of processing teeth 46a and 46a) closest to the equidistant arrangement in the circumferential direction are selected as shown by A to D in FIG. And each said process teeth 46a and 46a are formed in the position corresponded to each said division among the axial direction one end surfaces of the said main-body part 44a. In this case, the respective pressure Koha 46a, the circumferential center position of 46a, to coincide with the circumferential center positions of the respective compartment. In the case of this example, the processing teeth 46a, 46a are not provided in a positional relationship that is rotationally symmetric about the central axis of the main body 44a (hub main body 8).

Next, a method for forming the hub-side face spline 19 in the caulking portion 18 using the press device 54 of this example having the above-described configuration will be described.
When the hub-side face spline 19 is formed on the caulking portion 18 using the pressing device 54, an intermediate assembly (for supporting the wheel before the caulking portion 18 is formed on the cylindrical portion 17 of the hub body 8). In the state where the central axis of the hub body 8 constituting the rolling bearing unit) is aligned with the vertical direction in FIG. 7 (the axial direction one end of the hub body 8 is directed downward and the other axial direction is directed upward). The hub body 8 is fixed to the index table 51. Note that the vertical direction in FIG. 7 does not necessarily coincide with the vertical direction in use.

  Next, the oscillation mechanism 37 is operated to periodically reciprocate the face spline mold 55 in the vertical direction of FIG. Also in this example, the face spline mold 55 does not swing, rotate about its own central axis, or displace in the horizontal direction. That is, the face spline forming die 55 periodically reciprocates only in the vertical direction of FIG.

Simultaneously, the indexed rotating the hub body 8 fixed to the index table 51 by operating the indexing mechanism 39 at a predetermined angle theta _2. In the case of this example, the predetermined angle θ ₂ is set to 360 ° / 31 = 11.6 °. Note that there is no particular relationship between the timing of starting the operation of the oscillation mechanism 37 and the timing of starting the operation of the index mechanism 39. In the case of adopting a configuration in which the index drive unit 52 constituting the index mechanism 39 and the drive cylinder 42 constituting the oscillation mechanism 37 are driven by a common servo motor, the oscillation mechanism 37 and the index The mechanism 39 starts operating simultaneously. In this case, when a mechanism for synchronizing the operation of the index mechanism 39 and the operation of the oscillation mechanism 37 is incorporated, the oscillation mechanism 37 and the index mechanism 39 are in a synchronized state. Start operation.

Then, in the state where the oscillation mechanism 37 and the index mechanism 39 are operated as described above, the processing teeth 46a, 46a of the face spline mold 55 are connected to the axial direction of the caulking portion 18 of the hub body 8, and the like. The hub side face spline 19 is formed by pressing against the end face.
Specifically, at the timing when the hub body 8 is not rotating, the face spline forming die 55 is displaced downward by the oscillation mechanism 37 so as to form the face splines of the processing teeth 46a and 46a. The portions 53 and 53 are pressed against the other end surface in the axial direction of the caulking portion 18. In other words, the processing teeth 46a and 46a are pressed against the other end surface in the axial direction of the caulking portion 18 so that the face spline mold 55 is displaced downward by the oscillation mechanism 37. In this state, the hub body 8 is not index-rotated {see FIG. 5A}. At this time, the face spline forming portions 53 and 53 of the processing teeth 46a and 46a all press the other end surface in the axial direction of the caulking portion 18 at the same time. Accordingly, the face spline forming portions 53, 53 of the respective processing teeth 46a, 46a are operated once to press the other end surface in the axial direction of the caulking portion 18, and the other end surface in the axial direction of the caulking portion 18 is circumferential. The four positions in the direction are simultaneously pressed (plastically deformed).
On the other hand, at the timing when the hub body 8 is rotating, the face spline mold 55 is displaced upward by the oscillation mechanism 37, and the processing teeth 46a, 46a of the face spline mold 55 are The caulking portion 18 is separated from the other axial end surface. In other words, the face spline mold 55 is displaced upward by the oscillation mechanism 37 so that the machining teeth 46a, 46a of the caulking mold 38 are moved in the axial direction of the caulking portion 18, and the like. The hub body 8 is index-rotated while being separated from the end face {see FIG. 5B}.

  By repeating the above-described operation, the other end surface in the axial direction of the caulking portion 18 is plastically deformed to form the hub-side face spline 19. Then, when the groove depth of the hub-side face spline 19 (element recess 71) reaches a predetermined depth, the processing is finished. The manner in which the hub-side face spline 19 is formed will be described with reference to FIG. FIG. 10 is a schematic diagram showing a state in which one groove portion of the hub-side face spline 19 is formed. First, when each of the processing teeth 46a and 46a presses the end face in the axial direction against the caulking portion 18, an elementary recess 71 is formed in the pressed portion. At this time, the material constituting the caulking portion 18 tends to escape in the circumferential direction without escaping radially outward of the caulking portion 18. For this reason, the both sides in the circumferential direction of the element recesses 71 in the caulking part 18 are raised to form element protrusions 72. When the above-described operation is repeated, the elementary recesses 71 become deeper and the heights of the elementary projections 72 become higher.

Further, in the case of this example, the stroke adjustment mechanism controls the oscillation stroke of the oscillation mechanism 37 in accordance with the change in the depth of the elementary recess 71 and the height of each elementary projection 72 as described above. I try to increase the size.
Specifically, the hub body 8 and the processing teeth 46a, 46a are the largest central angle (in this example, among the central angles of the processing teeth 46a, 46a adjacent to each other in the circumferential direction. In FIG. 9, the oscillation stroke of the oscillation mechanism 37 at the time of relative rotation of the machining teeth formed at the position indicated by A and the respective machining teeth formed at the position indicated by B or C). Increase the size of. In other words, in the case of this example, the size of the oscillation stroke of the oscillation mechanism 37 is increased when the hub body 8 has been index-rotated eight times. Note that increasing the stroke size means reducing the lower limit of the stroke and increasing the upper limit. The position of the face spline mold 55 accompanying such a change in stroke is managed using a precise measuring instrument such as a linear scale.

Hereinafter, the operation of the stroke adjusting mechanism will be described with reference to FIG. In FIG. 11, for convenience of description, the stroke adjusting mechanism is operated when the index is rotated three times. In the case of the structure of this example, the stroke adjusting mechanism is operated when the index is rotated eight times. . First, at the time indicated by X ₁ in FIG. 11, for machining the stroke of oscillation of the oscillation mechanism 37 as A _1. Further, the time indicated by Y ₁ in FIG. 11 (time rotated a predetermined number of times index, in this example, 8 times), the change of the stroke to A _2, in the range indicated by X ₂ in FIG. 11, the stroke the performing the processing as _{a 2.} Further, at the time shown in FIG. 11 by _{Y 2,} by changing the stroke _{A 3,} in the range indicated by _{X 3} in FIG. 11, for machining the stroke as _{A 3.} Such a stroke change is adjusted so that the processing teeth 46a, 46a and the respective convex portions 72 do not interfere with each other during index rotation. In other words, the size of the stroke is appropriately determined depending on the relationship between the processing teeth 46 a and 46 a, the depth of the elementary recess 71, and the elementary projection 72.

According to the rolling bearing unit manufacturing method and the rolling bearing unit manufacturing apparatus (the face spline press device 54) having the above-described configuration, the other axial end surface of the inner ring 9 constituting the hub 4 is provided. In the rolling bearing unit having a structure restrained by the caulking portion 18, even when the hub side face spline 19 is formed on the other axial end surface of the caulking portion 18, the caulking portion 18 extends to the inner ring 9. It is possible to prevent the applied axial force from being biased with respect to the circumferential direction of the inner ring 9.
That is, in the manufacturing method of the rolling bearing unit of this example, the hub main body 8 is index-rotated and the face spline mold 55 is periodically reciprocated in the axial direction of the hub main body 8. Then, in a state where the hub body 8 is not index rotated, the caulking mold 38 is displaced only in the axial direction of the hub body 8 without swinging, so that the face spline mold 55 is entirely The hub-side face spline 19 is formed by simultaneously pressing the face spline forming portion 53 of the machining teeth 46a, 46a against the other axial end of the hub body 8. For this reason, when forming the hub-side face spline 19, it is possible to prevent a knitting load from being applied to the caulking portion 18, and the axial force applied from the caulking portion 18 to the inner ring 9 is applied to the inner ring 9. It is possible to avoid bias in the circumferential direction.
Other structures, functions, and effects are the same as those in the first example of the embodiment described above.

[Third example of embodiment]
A third example of the embodiment of the present invention will be described with reference to FIG. The rolling bearing unit manufacturing apparatus (face spline press apparatus) of this example is also a hub that is an uneven part in the circumferential direction on the other end face in the axial direction of the caulking part 18 as in the second example of the embodiment described above. This is for forming the side face spline 19. However, the face spline forming die 55a is different from the structure of the second example of the embodiment described above. Since the structure other than the face spline mold 55a is the same as the structure of the second example of the embodiment described above, the structure of the face spline mold 55a will be described below.

As with the face spline mold 55 of the second example of the embodiment described above, the face spline mold 55a has a plurality of main body portions 44b and gripped portions 45b (in this example, 12 pieces). Machined teeth 46b, 46b.
The main body 44b includes a cylindrical large-diameter portion 47b and a circle formed so as to protrude from the center of one axial end surface (the lower end surface in FIG. 12) of the large-diameter portion 47b to one axial side. It consists of a columnar small diameter part 48b. Of the one end face in the axial direction of the main body portion 44b, the radially inner end of the one end face in the axial direction of the large diameter portion 47b is located at four positions in the circumferential direction of the one end face in the axial direction of the large diameter portion 47b. Engaging grooves 49b are formed radially from an edge (a radially outer end edge of the other end surface in the axial direction of the small diameter portion 48b) to a radially outer end edge of one axial end surface of the large diameter portion 47b. . In the case of this example, the circumferential width (center angle) of each engaging groove 49b is three times the circumferential width (center angle) of the engaging groove 49a of the second example of the embodiment described above. It is. Each of the engaging grooves 49b as described above is also formed in a fan shape in which the shape seen from the axial direction increases in width in the circumferential direction as it goes outward in the radial direction.

The gripped portion 45b has a columnar shape, and is formed in a state of protruding in the other axial direction on the other axial end surface of the large diameter portion 47b.
Each forming teeth 46b, 46b, the In the state assembled to the main body portion 44b, the shape as viewed from the axial direction of the body portion 4 4b is body increases toward radially outward of the body portion 44b The portion 44b is formed in a substantially triangular shape in which the width dimension in the circumferential direction is increased. Each of the processing teeth 46b, 46b is formed with a face spline forming portion 53 on one end surface (the lower end surface in FIG. 12) in the axial direction of the main body portion 44b in a state assembled to the main body portion 44b. ing. Each of the machined teeth 46b, 46b having such a configuration includes three machined teeth 46b, 46b as one machined tooth set 56, and a total of 4 machined tooth groups 56, 56 are respectively associated with the respective engagement teeth. It is press-fitted and fixed to the mating grooves 49b and 49b. Thus, in the state assembled | attached to the said main-body part 44b, the other half part (upper half part of FIG. 12) regarding the axial direction of this main-body part 44b among each said processing teeth 46b and 46b is this main-body part. 44b is press-fitted into the engaging grooves 49b, 49b. On the other hand, the axial half piece (the lower half part of FIG. 12) of each of the processing teeth 46b, 46b protrudes from the axial end face of the large-diameter portion 47b to one axial side. In the case of this example, the processing teeth 46b, 46b are not arranged at equal intervals in the circumferential direction of the main body 44b (hub main body 8). However, each processing tooth 46b, 46b (each processing tooth set 56, 56) is provided in a positional relationship (four-fold symmetry) that is rotationally symmetric about the central axis of the main body 44b (hub main body 8). Yes.
The face spline mold 55 a having such a configuration is assembled in a state where the gripped portion 45 b is gripped by the gripping tool 43 of the oscillation mechanism 37.

In the case of this example, the number of teeth of the hub-side face spline 19 formed in the caulking portion 18 is 30. Further, the center angle theta ₃ of the respective machining tooth 46b, is set to 12 °. Therefore, the center angle of one set of processing tooth set 56 is 36 °.

The method of forming the hub-side face spline 19 in the caulking portion 18 using the press device 54 of the present example having the above-described configuration is substantially the same as the second example of the above-described embodiment.
Especially in the case of this example, the predetermined angle theta ₂ when the index table 51 (the hub main body 8) is indexed rotating by the index mechanism 39 (see FIG. 1) is set to 36 °. That is, in the case of this example, the index table 51 (hub main body 8) is intermittently rotated by the central angle (36 °) of each processing tooth set 56, 56.
Also in this example, as in the second example of the above-described embodiment, the stroke of the oscillation mechanism 37 is increased by the stroke adjusting mechanism during machining. (See FIG. 13). This point will be described with reference to FIG. FIG. 13 is a schematic view showing a state in which the hub body 8 is pressed by the processing tooth sets 56, 56.
First, when machining is started, each machining tooth 46b, 46b constituting each machining tooth set 56, 56 is a portion (center angle) of the other end face in the axial direction of the caulking portion 18 shown in FIG. Is pressed at 36 °. In this state, the portion shown by the coarse oblique lattice in FIG. 13 (the portion having a central angle of 36 °) and the plain portion (the portion having a central angle of 12 °) are not pressed. Next, when the hub body 8 is index-rotated, each of the processing teeth 46b and 46b presses a portion indicated by a rough diagonal lattice in FIG. In this state, the portion indicated by the solid color in FIG. 13 is not pressed. Next, when the hub body 8 is index-rotated, the respective processing teeth 46b, 46b are arranged on one side in the circumferential direction (counterclockwise in FIG. 13) of the portion indicated by the plain in FIG. 13 and the portion indicated by the fine diagonal lattice. Press the 2/3 part. In this state, all the portions of the other end surface in the axial direction of the caulking portion 18 where the concave portion of the hub-side face spline 19 is formed are pressed. In other words, a portion of the other end surface in the axial direction of the caulking portion 18 where the concave portion of the hub-side face spline 19 is formed is pressed (dented in one axial direction) by the same amount. . In this example, after such a state is reached, the size of the oscillation stroke of the oscillation mechanism 37 is increased. Thereafter, each time the portion of the other end surface in the axial direction of the caulking portion 18 where the concave portion of the hub-side face spline 19 is formed is pressed by the same amount (dented in one axial direction), The oscillation stroke of the oscillation mechanism 37 is increased. Note that the basic operation of the stroke adjusting mechanism is the same as that of the second example of the stroke adjusting mechanism of the embodiment described with reference to FIG.

According to this example having the above-described configuration, the time required to form the hub-side face spline 19 can be shortened compared to the case of the second example of the above-described embodiment. In the case of this example, the processing tooth set 56, 56 is configured by the three processing teeth 46b, 46b, but may be configured by the two processing teeth 46b, 46b.
Other structures, operations, and effects are the same as those in the second example of the embodiment described above.

In each example of the embodiment described above, a so-called fourth generation wheel support rolling bearing unit is targeted. However, the present invention can also be applied to a wheel support rolling bearing unit other than the fourth generation.
Moreover, the number of the processing teeth which comprise the processing surface of a shaping | molding die is not limited to the case of each example of embodiment mentioned above.
Further, the pressing portion of the mold is not limited to the structure provided separately from the main body portion 44 (the processing teeth 46 and 46) as in each example of the embodiment described above, but also to the main body portion 44. An integrally formed structure can also be used.

DESCRIPTION OF SYMBOLS 1 Rolling bearing unit for wheel support 2 Outer ring for constant velocity joint 3 Outer ring 4 Hub 5 Rolling element 6 Stationary side flange 7a, 7b Outer ring raceway 8 Hub body 9 Inner ring 10 Rotation side flange 11a, 11b Inner ring raceway 12 Small diameter step 13 Central hole 14 bolt 15 flange 16 small diameter part 17 cylindrical part 18 caulking part 19 hub side face spline 20 mouse part 21 end wall part 22 shaft part 23 female thread part 24 joint side face spline 25 male thread part 26 head part 27 constant velocity joint inner ring 28 Ball 29a, 29b Cage 30 Roll 31 Convex part (processing tooth)
32 Concave portion 33 Processed surface 34, 34a Caulking press device 35 Base 36 Device body 37, 37a Oscillation mechanism 38 Caulking mold 39, 39a Index mechanism 40 Column portion 41 Support portion 42, 42a Drive cylinder 43, 43a Holding tool 44 44a, 44b Main body part 45, 45a, 45b Grip part 46, 46a, 46b Processing teeth 47, 47a, 47b Large diameter part 48, 48a, 48b Small diameter part 49, 49a, 49b Engaging groove 50 Caulking recess 51 , 51a Index table 52, 52a Index drive section 53 Face spline forming section 54, 54a Face spline press 55, 55a Face spline mold 56 Machining tooth set 57 Transfer machine 58 Lower fixed base 59 Upper fixed base 60a, 6 b support 61 synchronizing rod 62 servomotor 63 upward drive gear 64 crank gear 65 connecting rod 66 the rack 67 driving serration 68 driven side tooth portion 69 downward driving gear 70 driving side teeth 71 Moto凹部 72 Motototsu unit

Claims (20)

In order to apply a coupling force directed to one side in the axial direction with respect to the hub body to the outer ring fitted on the hub body, the cylindrical portion provided at the other axial end of the hub body is radially outward. In order to make a rolling bearing unit that suppresses the other axial end surface of the inner ring by a caulking portion formed by plastic deformation,
Using a mold having pressing parts at multiple locations in the circumferential direction on one side in the axial direction,
Based on the relative rotation of the hub body and the mold intermittently by a predetermined angle, and reciprocating the mold in the axial direction of the hub body,
In a state where the hub body and the mold are not relatively rotated, each pressing portion of the mold is pressed against the other axial end of the hub body,
In a state where the hub body and the mold are relatively rotated, each pressing portion of the mold is separated from the other axial end of the hub body,
A method for manufacturing a rolling bearing unit, wherein the caulking portion is formed. The method for manufacturing a rolling bearing unit according to claim 1, wherein the predetermined angle is equal to or less than a central angle of the pressing portion. A reference height that is the height of the mold when the mold is in the highest state among the strokes of the reciprocating motion when the entire circumference of the other axial end surface of the cylindrical portion is pressed by the same amount. The method of manufacturing a rolling bearing unit according to claim 1, wherein the height is displaced by a predetermined amount toward the hub body. By reciprocating the mold in the axial direction of the hub body at a frequency of 50 to 200 Hz, and displacing the reference height of the mold toward the hub body at a speed of 1 to 5 mm / sec, The method of manufacturing a rolling bearing unit according to claim 3, wherein the mold is pressed against the other axial end of the hub body with a load of 49 to 196 kN. The relationship between the reciprocal number N and the hoop stress generated on the outer peripheral surface of the inner ring is obtained when the reciprocal number of the ratio of the central angle per pressing portion in the circumferential direction of the mold is N. Based on this relationship, the central angle per one pressing portion is determined so that the hoop stress is smaller than a predetermined reference value. A manufacturing method of a rolling bearing unit given in any 1 paragraph of Claim 3 or 4 quoted automatically. In order to apply a coupling force directed to one side in the axial direction with respect to the hub body to the outer ring fitted on the hub body, the cylindrical portion provided at the other axial end of the hub body is radially outward. The other end surface in the axial direction of the inner ring is held down by a caulking portion formed by plastic deformation, and a hub side face spline that is an uneven portion in the circumferential direction is formed on the other end surface in the axial direction of the caulking portion. To make a rolling bearing unit,
Using a mold having pressing parts at multiple locations in the circumferential direction on one side in the axial direction,
Based on intermittently relatively rotating the hub body and the mold by a predetermined angle and reciprocating the mold in the axial direction of the hub body,
With the hub body and the mold not rotating relative to each other, the pressing parts of the mold are pressed against the other end surface in the axial direction of the caulking part,
In the state where the hub body and the mold are relatively rotated, by separating each pressing portion of the mold from the other end surface in the axial direction of the caulking portion,
A method for manufacturing a rolling bearing unit, wherein a hub-side face spline is formed on the other axial end surface of the caulking portion. The reciprocating motion of the mold with respect to the axial direction of the hub body each time the portion of the other end surface in the axial direction of the caulking portion where the concave portion of the hub-side face spline is formed is pressed by the same amount. The method for manufacturing a rolling bearing unit according to claim 6, wherein the magnitude of the amplitude is increased. When each of the pressing parts is a processing tooth having a central angle of 12 ° and three processing teeth arranged in the circumferential direction are set as one processing tooth set, The method for manufacturing a rolling bearing unit according to claim 6 or 7, wherein one having a total of four processing tooth sets on one side surface in the axial direction is used, and the predetermined angle is set to 36 °. The mold without rotating, the hub body, wherein is intermittently rotated by a predetermined angle with respect to the forming die, a rolling bearing unit as set forth in any one of claims 1-8 Production method. The mold according to any one of claims 1 to 9 , wherein the molding die has at least two pressing portions, and each pressing portion is disposed at a position that is rotationally symmetric with respect to the central axis of the molding die. A method for manufacturing a rolling bearing unit according to item 1. The molding die has N pressing portions, and each pressing portion is arranged at a position that is not rotationally symmetric with respect to the central axis of the molding die, and among the uneven portions constituting the hub-side face spline. When the number of recesses is M, and one side surface in the axial direction of the mold is divided into M sections at equal intervals in the circumferential direction, each pressing part has a circumference of the mold selected from the sections. 9. The method according to claim 9 or claim 9 or any one of claims 6 to 8, which is formed in N sections closest to the equidistant arrangement with respect to the direction. A method for manufacturing the rolling bearing unit according to 10 . In order to apply a coupling force directed to one side in the axial direction with respect to the hub body to the outer ring fitted on the hub body, the cylindrical portion provided at the other axial end of the hub body is radially outward. An apparatus for manufacturing a rolling bearing unit for producing a rolling bearing unit in which the other end surface in the axial direction of the inner ring is suppressed by a caulking portion formed by plastic deformation,
It has a mold, an oscillation mechanism, and an index rotation mechanism.
Of these, the mold has pressing portions at a plurality of locations in the circumferential direction on one side surface in the axial direction.
The oscillation mechanism is for reciprocating the mold in the axial direction of the hub body,
The index rotation mechanism is for intermittently rotating the hub body and the molding die intermittently by a predetermined angle;
The hub body and the mold are intermittently rotated relative to each other by a predetermined angle by the index rotation mechanism, and the mold is reciprocated in the axial direction of the hub body by the oscillation mechanism. Based on this, in a state where the hub body and the mold are not relatively rotated, the pressing portion of the mold is pressed against the other axial end of the hub body, so that the hub body and the mold are relatively A rolling bearing unit manufacturing apparatus having a function of separating each pressing portion of the mold from the other axial end portion of the hub body in a rotating state. The rolling bearing unit manufacturing apparatus according to claim 12, wherein the index rotation mechanism sets the predetermined angle to be equal to or less than a center angle of the pressing portion. The height of the mold when the mold is in the highest state among the reciprocating strokes of the mold when the entire circumference of the other axial end surface of the cylindrical portion is pressed by the same amount. The rolling bearing unit manufacturing apparatus according to claim 12, further comprising an axial feed mechanism that displaces a reference height that is a predetermined height toward the hub body. While the oscillation mechanism reciprocates the mold in the axial direction of the hub body at a frequency of 50 to 200 Hz, the shaft feed mechanism allows the mold to have a reference height of 1 to 5 mm / sec. The rolling according to claim 14, having a function of pressing the mold against the other axial end of the hub body with a load of 49 to 196 kN by displacing the hub body at a speed of 5 to 15 mm. Bearing unit manufacturing equipment. In order to apply a coupling force directed to one side in the axial direction with respect to the hub body to the outer ring fitted on the hub body, the cylindrical portion provided at the other axial end of the hub body is radially outward. The other end surface in the axial direction of the inner ring is suppressed by a caulking portion formed by plastic deformation, and a hub-side face spline that is an uneven portion in the circumferential direction is formed on the other end surface in the axial direction of the caulking portion. A rolling bearing unit manufacturing apparatus for producing a rolling bearing unit,
It has a mold, an oscillation mechanism, and an index rotation mechanism.
Of these, the mold has pressing portions at a plurality of locations in the circumferential direction on one side surface in the axial direction.
The oscillation mechanism is for reciprocating the mold in the axial direction of the hub body,
The index rotation mechanism is for intermittently rotating the hub body and the molding die intermittently by a predetermined angle;
The hub body and the mold are intermittently rotated relative to each other by a predetermined angle by the index rotation mechanism, and the mold is reciprocated in the axial direction of the hub body by the oscillation mechanism. Based on this, in a state where the hub body and the mold are not relatively rotated, each pressing portion of the mold is pressed against the other end surface in the axial direction of the caulking portion, and the hub body and the mold are relatively A rolling bearing unit manufacturing apparatus having a function of separating each pressing portion of the mold from the other axial end surface of the caulking portion in a rotating state. Each time the oscillation mechanism is in a state in which the portion of the other end surface in the axial direction of the caulking portion where the concave portion of the hub-side face spline is formed is pressed by the same amount, the axial direction of the hub body is The rolling bearing unit manufacturing apparatus according to claim 16, which has a function of increasing the amplitude of the reciprocating motion of the mold. In the case where each of the pressing parts is a processing tooth having a central angle of 12 °, and the three processing teeth arranged in the circumferential direction are set as one processing tooth set. , On one side in the axial direction, it has a total of 4 processing tooth sets,
The rolling bearing unit manufacturing apparatus according to claim 16 or 17, wherein the index rotation mechanism has the predetermined angle of 36 °. The indexed rotating mechanism, without rotating the mold, said to intermittently rotate the hub body by the predetermined angle, producing a rolling bearing unit as set forth in any one of claims 12 to 18 apparatus. A method of manufacturing a vehicle including a rolling bearing unit,
The rolling bearing unit is manufactured by the method for manufacturing a rolling bearing unit according to any one of claims 1 to 11, or of the rolling bearing unit according to any one of claims 12 to 19. A manufacturing method of a vehicle manufactured using a manufacturing apparatus.