US20030146591A1 - Wheel driving unit and method of manufacturing the same - Google Patents

Wheel driving unit and method of manufacturing the same Download PDF

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Publication number
US20030146591A1
US20030146591A1 US10/296,126 US29612602A US2003146591A1 US 20030146591 A1 US20030146591 A1 US 20030146591A1 US 29612602 A US29612602 A US 29612602A US 2003146591 A1 US2003146591 A1 US 2003146591A1
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United States
Prior art keywords
spline
male
peripheral surface
portions
teeth
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US10/296,126
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English (en)
Inventor
Hideo Ouchi
Takeo Ohkuma
Kiyoshi Okubo
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
NSK Ltd
Original Assignee
NSK Ltd
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Filing date
Publication date
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Assigned to NSK LTD. reassignment NSK LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: OHKUMA, TAKEO, OKUBO, KIYOSHI, OUCHI, HIDEO
Publication of US20030146591A1 publication Critical patent/US20030146591A1/en
Priority to US11/079,170 priority Critical patent/US7104893B2/en
Abandoned legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21K—MAKING FORGED OR PRESSED METAL PRODUCTS, e.g. HORSE-SHOES, RIVETS, BOLTS OR WHEELS
    • B21K25/00—Uniting components to form integral members, e.g. turbine wheels and shafts, caulks with inserts, with or without shaping of the components
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21J—FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
    • B21J5/00—Methods for forging, hammering, or pressing; Special equipment or accessories therefor
    • B21J5/06—Methods for forging, hammering, or pressing; Special equipment or accessories therefor for performing particular operations
    • B21J5/12—Forming profiles on internal or external surfaces
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21K—MAKING FORGED OR PRESSED METAL PRODUCTS, e.g. HORSE-SHOES, RIVETS, BOLTS OR WHEELS
    • B21K1/00—Making machine elements
    • B21K1/06—Making machine elements axles or shafts
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60B—VEHICLE WHEELS; CASTORS; AXLES FOR WHEELS OR CASTORS; INCREASING WHEEL ADHESION
    • B60B27/00—Hubs
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D1/00—Couplings for rigidly connecting two coaxial shafts or other movable machine elements
    • F16D1/10—Quick-acting couplings in which the parts are connected by simply bringing them together axially
    • F16D1/108—Quick-acting couplings in which the parts are connected by simply bringing them together axially having retaining means rotating with the coupling and acting by interengaging parts, i.e. positive coupling
    • F16D1/116—Quick-acting couplings in which the parts are connected by simply bringing them together axially having retaining means rotating with the coupling and acting by interengaging parts, i.e. positive coupling the interengaging parts including a continuous or interrupted circumferential groove in the surface of one of the coupling parts
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D3/00—Yielding couplings, i.e. with means permitting movement between the connected parts during the drive
    • F16D3/16—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts
    • F16D3/20—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts one coupling part entering a sleeve of the other coupling part and connected thereto by sliding or rolling members
    • F16D3/202—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts one coupling part entering a sleeve of the other coupling part and connected thereto by sliding or rolling members one coupling part having radially projecting pins, e.g. tripod joints
    • F16D3/205—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts one coupling part entering a sleeve of the other coupling part and connected thereto by sliding or rolling members one coupling part having radially projecting pins, e.g. tripod joints the pins extending radially outwardly from the coupling part
    • F16D3/2055—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts one coupling part entering a sleeve of the other coupling part and connected thereto by sliding or rolling members one coupling part having radially projecting pins, e.g. tripod joints the pins extending radially outwardly from the coupling part having three pins, i.e. true tripod joints
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D3/00—Yielding couplings, i.e. with means permitting movement between the connected parts during the drive
    • F16D3/16—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts
    • F16D3/20—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts one coupling part entering a sleeve of the other coupling part and connected thereto by sliding or rolling members
    • F16D3/22—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts one coupling part entering a sleeve of the other coupling part and connected thereto by sliding or rolling members the rolling members being balls, rollers, or the like, guided in grooves or sockets in both coupling parts
    • F16D3/223—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts one coupling part entering a sleeve of the other coupling part and connected thereto by sliding or rolling members the rolling members being balls, rollers, or the like, guided in grooves or sockets in both coupling parts the rolling members being guided in grooves in both coupling parts
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D1/00—Couplings for rigidly connecting two coaxial shafts or other movable machine elements
    • F16D1/10—Quick-acting couplings in which the parts are connected by simply bringing them together axially
    • F16D2001/103—Quick-acting couplings in which the parts are connected by simply bringing them together axially the torque is transmitted via splined connections
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D3/00—Yielding couplings, i.e. with means permitting movement between the connected parts during the drive
    • F16D3/16—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts
    • F16D3/20—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts one coupling part entering a sleeve of the other coupling part and connected thereto by sliding or rolling members
    • F16D3/22—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts one coupling part entering a sleeve of the other coupling part and connected thereto by sliding or rolling members the rolling members being balls, rollers, or the like, guided in grooves or sockets in both coupling parts
    • F16D3/223—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts one coupling part entering a sleeve of the other coupling part and connected thereto by sliding or rolling members the rolling members being balls, rollers, or the like, guided in grooves or sockets in both coupling parts the rolling members being guided in grooves in both coupling parts
    • F16D2003/22326—Attachments to the outer joint member, i.e. attachments to the exterior of the outer joint member or to the shaft of the outer joint member
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D2250/00—Manufacturing; Assembly
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D2300/00—Special features for couplings or clutches
    • F16D2300/12—Mounting or assembling
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S464/00—Rotary shafts, gudgeons, housings, and flexible couplings for rotary shafts
    • Y10S464/904—Homokinetic coupling
    • Y10S464/906—Torque transmitted via radially spaced balls

Definitions

  • a wheel-driving unit is used not only to support drive wheels ⁇ the front wheels of an FF car (a front-engine front-wheel-drive car), the rear wheels of an FR car (a front-engine rear-wheel-drive car) and an RR car (a rear-engine rear-wheel-drive car) , and all wheels of a 4WD car (a four-wheel-drive car) ⁇ supported on the independent suspension in such a manner that the drive wheels can be rotated with respect to the suspension, but also to drive or rotate these drive wheels.
  • FF car front-engine front-wheel-drive car
  • FR car a front-engine rear-wheel-drive car
  • RR car a rear-engine rear-wheel-drive car
  • a wheel-driving unit consisting of a combination of a wheel-driving bearing unit and a constant velocity joint unit structured such that a differential-side constant velocity joint and a wheel-side constant velocity joint are respectively connected to the both end portions of a drive shaft.
  • the present invention relates to a wheel-driving unit of the above type.
  • FIG. 39 shows an ordinary wheel-driving bearing unit structured for the above purpose such that a wheel-supporting bearing unit 1 and a wheel-side constant velocity joint 2 are combined together.
  • the wheel-supporting bearing unit 1 is structured such that a hub 4 and an inner ring 5 are rotatably supported on the inside diameter side of an outer ring 3 through a plurality of rolling elements 6 , 6 .
  • the outer ring 3 is connected and fixed to a knuckle 8 (see FIG. 40 which will be discussed later), which constitutes the suspension, through an outwardly-facing flange-shaped mounting portion 7 formed in the outer peripheral surface of the outer ring 3 , while the outer ring 3 does not rotate even when it is in use.
  • the outer peripheral surface of the outer ring 3 is formed as a simple cylindrical surface (which does not include the mounting portion 7 ) and is fitted with and fixed to the inner surface of a support hole formed in the knuckle 8 .
  • the inner peripheral surface of the outer ring 3 there are formed a double row of outer. raceways 9 , 9 ; and, the hub 4 and inner ring 5 are supported on the inside diameter side of the outer ring 3 in such a manner that they are concentric with the outer ring 3 and can be rotated.
  • a first inner raceway 11 in the middle portion of the outer peripheral surface of the hub 4 , there is formed a first inner raceway 11 and, similarly, the inner ring 5 having a second inner raceway 13 formed in the outer peripheral surface thereof is fitted with and fixed to the outer surface of a small-diameter stepped portion 12 formed in the portion that is near to the inner (with respect to the axial direction thereof, when the wheel-supporting bearing unit 1 is incorporated into a car, the width-direction central side of the car: and, this applies similarly in the whole of the present specification; that is, the right side of the respective figures except for FIGS. 4, 7, 10 , 13 , 25 , 26 , 28 , 32 , 37 and 38 ) end portion of the outer peripheral surface of the hub 4 .
  • a spline hole 14 in the central portion of the hub 4 .
  • the wheel-side constant velocity joint 2 comprises an outer ring 15 for a constant velocity joint, an inner ring 16 for a constant velocity joint, and a spline shaft 17 .
  • the outer ring 15 for a constant velocity joint and spline shaft 17 form a drive member 18 . That is, the spline shaft 17 is disposed on the outer end portion of the drive member 18 and can be engaged with the spline hole 14 ; and, the outer ring 15 for a constant velocity joint is disposed on the inner end portion of the drive member 18 .
  • outside engaging grooves 19 , 19 In a plurality of portions in the circumferential direction of the inner peripheral surface of the outer ring 15 for a constant velocity joint, there are formed outside engaging grooves 19 , 19 in such a manner that they respectively extend at right angles to the present circumferential direction. Also, in the case of the inner ring 16 for a constant velocity joint which forms the wheel-side constant velocity joint 2 , in the central portion thereof, there is formed a second spline hole 20 and, in the portions of the outer peripheral surface thereof that correspond to the outside engaging grooves 19 , 19 , there are formed inside engaging grooves 21 , 21 in such a manner that they respectively extend at right angles to the circumferential direction of the outer peripheral surface of the inner ring 16 .
  • Balls 22 , 22 are interposed between the inside engaging grooves 21 , 21 and outside engaging grooves 19 , 19 and are held by a retainer 23 in such a manner that they are allowed to roll along these engaging grooves 21 , 19 .
  • the shapes of the composing parts of the wheel-side constant velocity joint 2 are similar to those of a constant velocity joint of a Zwepper type or a bar field type and are not related to the gist of the invention and, therefore, the detailed description thereof is omitted here.
  • the spline shaft 17 is inserted into the spline hole 14 of the hub 4 from the inside to the outside with respect to the axial direction of the hub 4 .
  • a nut 25 is threadedly engaged with a male screw portion 24 formed in such portion of the outer end portion of the spline shaft 17 that projects from the outer end face of the hub 4 and, by fastening the nut 25 and male screw portion 24 further, they can be connected and fixed to each other.
  • the inner end face of the inner ring 5 is contacted with the outer end face of the outer ring 15 for a constant velocity joint, there by preventing the inner ring 5 from shifting in a direction where it can slip out of the small-diameter stepped portion 12 .
  • a proper preload is applied to the respective rolling elements 6 , 6 .
  • a male spline portion 27 formed in the outer end portion of a drive shaft 26 is spline engaged into the second spline hole 20 formed in the central portion of the inner ring 16 for a constant velocity joint.
  • a retaining ring 29 which is secured to a securing groove 28 formed so as to exist over the entire periphery of the outer peripheral surface of the outer end portion of the male spline portion 27 , is engaged with a securing stepped portion 30 formed in the peripheral edge portion of the outer end of the second spline hole 20 , thereby preventing the male spline portion 27 from slipping out of the second spline hole 20 .
  • the inner end portion of the drive shaft 26 is connected to the output portion of a tripod-type constant velocity joint which is a differential-side constant velocity joint.
  • the tripod-type constant velocity joint, the drive shaft 26 and the wheel-side constant velocity joint 2 cooperate together in forming the above-mentioned constant velocity joint unit.
  • the present constant velocity joint unit is combine with the wheel-supporting bearing unit 1 to thereby form the above-mentioned wheel-driving unit.
  • FIG. 40 Also, in the specification of U.S. Pat. No. 4,881,842, there is disclosed such a wheel-driving bearing unit as shown in FIG. 40.
  • a hub 4 a is rotatably supported inside an outer ring 3 fixed to a knuckle 8 by a double row of rolling elements 6 , 6 .
  • the spline shaft 17 of a drive member 18 a is spline engaged into a spline hole 14 formed in the central portion of the hub 4 a .
  • a securing portion 31 for securing thereto a tool which is used to draw the spline shaft 17 into the spline hole 14 .
  • An incomplete-circular-ring-shaped retaining ring 33 is bridgingly interposed between a securing groove 32 , which is formed in the near-to-leading-end portion of the outer peripheral surface of the spline shaft 17 and serves as an inside engaging portion, and a securing stepped portion 35 which is formed in such portion of the inner peripheral surface of the hub 4 a that is opposed to the securing groove 32 and also which serves as an outside engaging portion, thereby preventing the spline shaft 17 from slipping out of the hub 4 a .
  • an elastic ring 34 is elastically compressed between the hub 4 a and an outer ring 15 for a constant velocity joint disposed on the drive member 18 a.
  • an inner ring 5 having a second inner raceway 13 formed in the outer peripheral surface thereof is fitted with the outer surface of the near-to-inner-end portion of the hub 4 a and, at the same time, a retaining ring 37 is secured to a securing groove 36 formed over the entire periphery of the outer peripheral surface of such portion of the inner end portion of the hub 4 a that projects inwardly in the axial direction beyond the inner end face of the inner ring 5 .
  • the retaining ring 37 holds the inner end face of the inner ring 5 to thereby prevent the inner ring 5 from shifting in the axial direction thereof.
  • the operation to connect together the wheel-supporting bearing unit 1 and wheel-side constant velocity joint 2 is troublesome, the operation gives rise to an increase in the cost necessary for assembling of the wheel-driving bearing unit. Also, separate provision of the male screw portion 24 and nut 25 increases both size and weight of the wheel-driving bearing unit.
  • the retaining ring 33 may only be interposed between the inner peripheral surface of the outer end portion of the hub 4 a and the outer peripheral surface of the outer end portion of the spline shaft 17 .
  • the operation to connect together the wheel-supporting bearing unit la and wheel-side constant velocity joint 2 a can be executed easily, which only can reduce the cost necessary for assembly of the structure but also can reduce the size and weight thereof.
  • JP-A-10-264605 there is disclosed such a wheel-driving bearing unit as shown in FIG. 41.
  • a wheel-supporting rolling bearing unit 1 b forming part of the present wheel-driving bearing unit
  • an outer ring 15 a for a constant velocity joint which corresponds to a drive member set forth in the appended claims thereof and forms a wheel-side constant velocity joint 2 b .
  • the intermediate seat 38 which is formed in a short-cylindrical shape, in the inner peripheral surface thereof, there is formed an inside-diameter-side female spline portion 39 ; and, in the outer peripheral surface thereof, there is formed an outside-diameter-side male spline portion 40 which corresponds to a first spline portion set forth in the appended claims of the present specification.
  • the intermediate seat 38 is assembled to the inner end portion of the hub 4 b by spline engaging an inside-diameter-side male spline portion 41 formed in the outer peripheral surface of the inner end portion of the hub 4 b with the inside-diameter-side female spline portion 39 with no shaky motion between them.
  • a retaining ring 33 a is bridgingly interposed between the outside-diameter-side female spline portion 43 and outside-diameter-side male spline portion 40 that are mutually spline engaged, thereby preventing the outer ring 15 a for a constant velocity joint and the intermediate seat 38 from being separated from each other.
  • the incomplete-circular-ring-shaped retaining ring 33 a is bridgingly interposed between an inside securing groove 44 , which is formed over the entire periphery of the outer peripheral surface of the intermediate seat 38 and corresponds to a first engaging portion set forth in the appended claims of the present specification, and an outside securing groove 45 formed over the entire periphery of the inner peripheral surface of the outer end portion of the outer ring 15 a for a constant velocity joint and corresponding to a second engaging portion set forth in the appended claims of the present specification, thereby preventing the outer ring 15 a for a constant velocity joint and the intermediate seat 38 from moving in the axial direction of the present wheel-driving bearing unit.
  • the hub 4 b is rotatably supported on the inside diameter side of the outer ring 3 by a double-row angular-type ball bearing.
  • An inner ring 5 forming this ball bearing is held and fixed by and between the outer end face of the intermediate seat 38 and a stepped surface 46 existing in the outer end portion of a small-diameter stepped portion 12 formed in the outer peripheral surface of the middle portion of the hub 4 b.
  • the male and female spline portions 47 , 48 can be collided with each other, which raises a possibility that there can be generated teeth striking sounds which are offensive to the ear of an occupant of the car or a pedestrian present in the periphery of the car.
  • Such problem can be found also in the case of the third conventional structure shown in FIG. 41, that is, in the spline engaged portion 49 a composed of the outside-diameter-side male spline portion 40 formed in the outer peripheral surface of the intermediate seat 38 and the outside-diameter-side female spline portion 43 formed in the inner peripheral surface of the outer end portion of the outer ring 15 a for a constant velocity joint.
  • each of the teeth of the male spline portion 47 may be inclined (for example, about 10 min.) with respect to the center axis of the spline shaft 17 , that is, each tooth may be shaped so as to have such torsion angle.
  • the respective teeth of the female spline portion 48 which is to be spline engaged with the male spline portion 47 , are formed so as to be parallel to the center axis of the spline shaft 17 .
  • the surface of the male spline portion 47 is hardened in the following manner: that is, the outer peripheral surface of the spline shaft 17 is rolled to thereby form a given shape having the above-mentioned torsion angle and, after then, it is high frequency quenched.
  • the inner peripheral surface of the spline hole 14 is broached to thereby form a given shape and, after then, it is left un-quenched.
  • the male spline portion 47 is formed into a shape having a torsion angle to thereby prevent occurrence of the teeth striking sounds, since the side surfaces of the respective teeth of the male and female spline portions 47 , 48 are pressed against each other only in the axial-direction two end portions thereof, the pressure insertion force can be reduced.
  • the male spline portion 47 is formed into a shape having a torsion angle
  • the mutually associated teeth of the male and female spline portions 47 , 48 are pressed against each other only in the axial-direction two end portions thereof, there is a possibility that the contact surface pressure acting on the side surfaces of these teeth can increase up to an excessively high value.
  • the contact surface pressure becomes excessively high, there is a possibility that the teeth can be worn or plastically deformed in a relatively early stage. For this reason, the sufficient durability of the male and female spline portions 47 , 48 cannot be secured, which makes it difficult to prevent occurrence of the teeth striking sounds for a long period of time.
  • a wheel-driving unit and a method for manufacturing the same according to the invention are invented in view of the above-mentioned circumstances of the prior art.
  • the wheel-driving unit as set forth in claim 1 similarly to a conventionally known wheel-driving unit, is composed of a wheel-supporting bearing unit and a constant velocity joint unit combined together through a retaining ring.
  • the wheel-supporting bearing unit comprises: an outer ring including a double row of outer raceways formed in the inner peripheral surface thereof and unrotatable even when it is in use; a hub including a flange formed in the near-to-outer-end portion of the outer peripheral surface thereof for supporting the wheels of a car, and a first inner raceway formed directly or through a separately produced inner ring in the middle portion of the outer peripheral surface thereof, with an inner ring having a second inner raceway formed in the outer peripheral surface thereof fitted with and fixed to the near-to-inner-end portion of the outer peripheral surface of the hub; rolling elements respectively interposed between one of the above-mentioned two outer raceways and the above-mentioned first inner raceway as well as between the other outer raceway and the above-mentioned second inner raceway respectively by twos or more; and, a first spline portion disposed in a portion of the hub or in a portion of the peripheral surface of a member connected and fixed to the hub.
  • the constant velocity joint unit is composed of a combination of a differential-side constant velocity joint and a wheel-side constant velocity joint respectively connected to the both end portions of a drive shaft; and, the constant velocity joint unit further comprises a drive member including a second spline portion formed in the outer end portion thereof to be spline engaged with the first spline portion, while the inner end portion of the drive member is formed as an outer ring for a constant velocity joint which forms the wheel-side constant velocity joint.
  • the retaining ring is formed such that it has an incomplete circular-ring-like shape as a whole and it can be enlarged and reduced in diameter.
  • the retaining ring is bridgingly interposed between a first engaging portion disposed in a portion of the hub or in a portion of the peripheral surface of a member connected and fixed to the hub and a second engaging portion disposed in a portion of the peripheral surface of the outer end portion of the drive member to thereby prevent removal of the engagement between the first and second spline portions.
  • the circumferential-direction widths of at least part of the teeth are set to vary gradually in the axial direction thereof, so that, as the second spline portion is inserted into the first spline portion, the present teeth can bite into the groove portions of their mating spline portion.
  • FIG. 1 is a section view of a first embodiment of a wheel-driving unit according to the invention
  • FIG. 2 is an enlarged view of the left section of FIG. 1;
  • FIG. 3 is an enlarged view of the A portion of FIG. 2, showing the details of a male spline portion
  • FIG. 4 is a section view taken along the line B-B shown in FIG. 3;
  • FIG. 5 is an enlarged view of the right section of FIG. 1;
  • FIG. 6 is a partially omitted section view of a second embodiment of a wheel-driving unit according to the invention.
  • FIG. 7 is a perspective view of a retaining ring used in the second embodiment
  • FIG. 8 is a section view of a third embodiment of a wheel-driving unit according to the invention.
  • FIG. 9 is an enlarged view of the C portion of FIG. 8, showing the details of a male spline portion
  • FIG. 10 is a section view taken along the line D-D shown in FIG. 9;
  • FIG. 11 is a view seen from the same direction as FIG. 8 with a drive member taken out therefrom, showing a female spline portion disposed in the central portion of a hub;
  • FIG. 12 is an enlarged view of the E portion shown in FIG. 11;
  • FIG. 13 is a section view taken along the line F-F shown in FIG. 12;
  • FIG. 14 is an enlarged view of the G portion shown in FIG. 8;
  • FIG. 15 is a section view to show how to form a securing portion in the inner peripheral surface of the hub on the basis of the female spline portion;
  • FIG. 16 is a section view to show how to form a securing groove in the outer peripheral surface of a drive member on the basis of a male spline
  • FIG. 17 is a view similar to FIG. 14, showing a fourth embodiment of a wheel-driving unit according to the invention.
  • FIG. 18 is a partially omitted section view of a fifth embodiment of a wheel-driving unit according to the invention.
  • FIG. 19 is a partially omitted section view of a sixth embodiment of a wheel-driving unit according to the invention.
  • FIG. 20 is an enlarged view of the H portion shown in FIG. 19;
  • FIG. 21 is a partially omitted section view of a seventh embodiment of a wheel-driving unit according to the invention.
  • FIG. 22 is an enlarged view of the left section of FIG. 21;
  • FIG. 23 is an enlarged view of the right section of FIG. 21;
  • FIG. 24 is an enlarged view of the I portion shown in FIG. 22, showing a second embodiment of the shape of a male spline portion;
  • FIG. 25 is a section view of an eighth embodiment of a wheel-driving unit according to the invention, showing how to form a male spline tooth in the outer peripheral surface of a taper shaft to thereby provide a spline shaft;
  • FIG. 26 is a section view of the eighth embodiment, showing how to form a female spline tooth in the inner peripheral surface of a blank hole to thereby provide a spline hole;
  • FIG. 27 is a section view of a ninth embodiment of a wheel-driving unit according to the invention.
  • FIG. 28 is a view seen from laterally of FIG. 27 with a retaining ring taken out therefrom;
  • FIG. 29 is an enlarged view of the J portion shown in FIG. 27;
  • FIG. 30 is a view similar to FIG. 29, explaining the reason why an error in the shape dimension gives rise to the shaky motion;
  • FIG. 31 is a section view of a wheel-supporting unit, showing a state thereof in which it is combined with a constant velocity joint unit;
  • FIG. 32 is similar to FIG. 28, showing a second embodiment of a retaining ring
  • FIG. 33 is a section view of a tenth embodiment of a wheel-driving unit according to the invention.
  • FIG. 34 is a section view of an eleventh embodiment of a wheel-driving unit according to the invention.
  • FIG. 35 is a section view of a portion of a twelfth embodiment of a wheel-driving unit according to the invention, while the present portion corresponds to the K portion shown in FIG. 34;
  • FIG. 36 is a partially omitted section view of a thirteenth embodiment of a wheel-driving unit according to the invention.
  • FIG. 37 is a perspective view of a diameter reducing jig
  • FIG. 38 is a view taken from the direction of the arrow mark L shown in FIG. 37, explaining the reason for regulation of the width dimension of a projecting piece;
  • FIG. 39 is a section view of a first example of a conventional structure
  • FIG. 40 is a partially omitted section view of a second example of the conventional structure; and, FIG. 41 is a section view of a third example of the conventional structure.
  • reference character 1 , 1 a , 1 b , 1 c designates a wheel-supporting bearing unit, 2 , 2 a , 2 b , 2 c a wheel-side constant velocity joint, 3 an outer ring, 4 , 4 a , 4 b , 4 c a hub, 5 an inner ring, 6 a rolling element, 7 a mounting portion, 8 a knuckle, 9 an outer raceway, 10 a flange, 11 a first inner raceway, 12 a small-diameter stepped portion, 13 a second inner raceway, 14 a spline hole, 15 , 15 a an outer ring for a constant velocity joint, 16 an inner ring for a constant velocity joint, 17 a spline shaft, 18 , 18 a , 18 b a drive member, 19 an outside engaging groove, 20 a second spline hole, 21 an inside engaging groove, 22 a ball, 23 a retain
  • FIGS. 1 to 5 shows a first embodiment of a wheel-driving unit according to the invention, which corresponds only to the claim 1 that is appended to the present specification.
  • the invention is characterized in that, in order not only to facilitate the connecting operation of a wheel-supporting bearing unit 1 c and a wheel-side constant velocity joint 2 c but also to prevent teeth striking sounds from being generated in a spline engaged portion 49 b between a spline shaft 17 and a spline hole 14 , the mutually connecting portion between a hub 4 c and spline shaft 17 as well as the spline engaged portion 49 b are respectively improved in structure.
  • an inner ring 5 including a second inner raceway 13 formed in the outer peripheral surface thereof is fitted with the outer surface of a small-diameter stepped portion 12 formed in the near-to-inner-end portion of the hub 4 c which constitutes the wheel-supporting bearing unit 1 c .
  • a caulk portion 42 a in the inner end portion of the hub 4 c .
  • a securing groove 32 which corresponds to a second engaging portion as set forth in the claims that are appended to the present specification, is formed so as to extend over the entire periphery of the outer peripheral surface of the outer end portion of the spline shaft 17 which constitutes a drive member 18 b .
  • the retaining ring 33 b is previously mounted onto the securing groove 32 before the spline shaft 17 is inserted into the spline hole 14 .
  • the retaining ring 33 b When inserting the spline shaft 17 into the spline hole 14 , the retaining ring 33 b , while reducing the diameter thereof elastically, passes through the spline hole 14 . And, in a state where the retaining ring 33 b is matched in position to the securing stepped portion 35 a , the diameter of the retaining ring 33 b is elastically restored to its original size; and, after then, the retaining ring 33 b is bridgingly interposed between the securing stepped portion 35 a and securing groove 32 .
  • the outer-end-side opening of the central hole of the hub 4 c is closed with a cap 50 .
  • a seal ring 52 is fitted with the outside of the outer peripheral surface of a shoulder portion 51 formed in the base end portion of an outer ring 15 for a constant velocity joint which constitutes the drive member 18 b .
  • the seal ring 52 is elastically compressed between the inner surface of the caulk portion 42 a and the outer end face of the outer ring 15 for a constant velocity joint, thereby closing a clearance existing between the caulk portion 42 a and the outer end face of the outer ring 15 for a constant velocity joint.
  • the cap 50 and seal ring 52 prevent foreign substances such as rainwater from getting into the spline engaged portion 49 b between a male spline portion 47 a formed in the outer peripheral surface of the spline shaft 17 and a female spline portion 48 a formed in the inner peripheral surface of the spline hole 14 , thereby being able to keep the spline engaged portion 49 b from rusting.
  • the near-to-inner-end portion of a male spline portion 47 a which is formed in the outer peripheral surface of the spline shaft 17 and corresponds to a second spline portion set forth in the appended claims of the present specification, that is, the (x portion, the range of which is shown by the arrow mark in FIGS. 1 to 3 , is formed as a male-spline-side taper portion 54 in which the circumferential-direction widths of the respective spline teeth 53 , 53 (FIGS.
  • the circumferential-direction both-side surfaces of the male spline teeth 53 , 53 existing in the male-spline-side taper portion 54 are respectively inclined in the opposite directions by the same angle with respect to the axial direction.
  • the angle at which the both-side surfaces of the male spline teeth 53 , 53 are inclined with respect to the axial direction (the inclination angle) is set of the order of 0.5-2°.
  • the inclination angle is an angle formed by a virtual straight line parallel to the center axis and the one-side surfaces of the respective spline teeth. That is, this inclination angle is defined as a half value of an angle (taper angle) formed between the both-side surfaces of the respective spline teeth.
  • the expression that the circumferential-direction widths of the male spline teeth 53 , 53 vary means that, in the portions where the diameter-direction heights are the same (for example, in the addenda), the widths of the male spline teeth 53 , 53 vary.
  • the near-to-inner-end portion of a female spline portion 48 a which is formed in the inner peripheral surface of the spline hole 14 and corresponds to a first spline portion set forth in the appended claims of the present specification, that is, the a portion, the range of which is shown by the arrow mark in FIGS. 1 and 2, is formed as a female-spline-side taper portion 57 in which the circumferential-direction widths of the respective teeth constituting the female spline portion 48 a are set to vary gradually in such a manner that the widths decrease as they go backwardly in the insertion direction of the spline shaft 17 , that is, inwardly in the axial direction.
  • the widths of groove portions existing between the teeth adjoining each other in the circumferential direction, in the female-spline-side taper portion 57 increase gradually as they go toward the inner end side of the spline hole 14 , that is, toward the forward side of the insertion direction of the spline shaft.
  • the female-spline-side taper portion 57 and male-spline-side taper portion 54 are different from each other in the direction where the circumferential-direction widths of the teeth of the taper portions 54 , 57 of the respective spline portions 47 a , 48 a increase in the axial direction.
  • the both-side surfaces of the respective teeth are arranged parallel to the axial direction to thereby prevent the widths of the respective teeth and groove portions from varying over the entire length of the above-mentioned middle portion or outer half section.
  • the circumferential-direction both- side surfaces of the respective teeth of the female-spline-side taper portion 57 are inclined with respect to the axial direction by the same angle as in the case of the male-spline-side taper portion 54 .
  • the male-spline-side taper portion 54 is formed by rolling at the same time when the shapes of the remaining portions of the male spline portion 47 a are formed. Also, the axial-direction lengths of the respective male-spline-side and female-spline-side taper portions 54 , 57 are set in the range of 5-15mm.
  • the male-spline-side taper portion 54 and the female-spline-side taper portion 57 of the female spline portion 48 a are regulated in shape and dimension in the following manner: that is, in a state where the spline shaft 17 is inserted by a given length and the retaining ring 33 b secured to the securing groove 32 of the outer peripheral surface of the outer end portion of the spline shaft 17 is engaged with the securing stepped portion 35 a formed in the inner peripheral surface of the outer end portion of the hub 4 c , the two taper portions 54 , 57 can be fitted with each other with an interference between them.
  • a drive shaft 26 is spline engaged with the inside of an inner ring 16 for a constant velocity joint but also a retaining ring 29 is engaged between a securing groove 28 formed over the entire periphery of the outer peripheral surface of the outer end portion of the drive shaft 26 and a securing groove 58 formed over the entire periphery of the inner peripheral surface of the inner ring 16 for a constant velocity joint, whereby the present wheel-driving bearing unit is assembled to the car.
  • the inner end portion of the drive shaft 26 is connected to the central portion of a trunnion 61 (FIGS.
  • a tripod-type constant velocity joint 60 which is disposed on the output shaft portion 59 of a differential gear (not shown) and corresponds to such a differential-side constant velocity joint as set forth in the appended claims of the present specification.
  • a pair of boots 63 a , 63 b which are used to prevent grease against leakage.
  • Each of the boots 63 a , 63 b is structured such that the middle portion thereof has bellows-like shape and the boot is formed in a cylindrical shape as a whole.
  • the basic structure of the tripod-type constant velocity joint 60 is similar to a structure which is conventionally known and does not relate to the gist of the invention; and, therefore, the detailed description thereof is omitted here.
  • one boot 63 a which is disposed on the tripod-type constant velocity joint 60 side, is made of synthetic resin, so that the rigidity of one boot 63 a can be made relatively high.
  • the other boot 63 b which is disposed on the outer ring 15 for a constant velocity joint side, similarly to a structure which is conventionally generally used, is made of rubber. Therefore, the other boot 63 b is relatively low in rigidity.
  • a stopper 65 which is formed in a circular ring shape as a whole having an L-shaped section and is made of a metal plate, is fitted with and fixed to the inner surface of the outer end opening of the housing 62 . And, when the tripod-type constant velocity joint 60 is in transport, the stopper 65 prevents the plurality of rollers 64 from slipping unexpectedly out of the outer end opening of the housing 62 .
  • the side surfaces (which are opposed to each other in the circumferential direction) of the male spline teeth 53 , 53 and female spline teeth of the male and female spline-side taper portions 54 , 57 are contacted with each other almost uniformly over the entire axial-direction lengths of these taper portions 54 , 57 .
  • the male spline teeth 53 , 53 of such portion of the middle portion or outer half section of the male spline portion 47 a that is shifted more outwardly in the axial direction than the male-spline-side taper portion 54 are spline engaged with the female spline teeth of such portion of the middle portion or outer half portion of the female spline portion 48 a that is shifted more outwardly in the axial direction than the female-spline-side taper portion 57 .
  • the male and female spline portions 47 a , 48 a are regulated in shape and dimension accuracy in the following manner: that is, of the male and female spline portions 47 a , 48 a , between the side surfaces, which are opposed to each other in the circumferential direction, of the male spline teeth 53 , 53 and female spline teeth in such portions that are shifted more outwardly in the axial direction than the male-spline-side taper portion 54 and female-spline-side taper portion 57 , there exists a minute clearance equal to or less than 100 ⁇ m or there exists no clearance at all.
  • the circumferential-direction widths of the male spline teeth 53 , 53 and female spline teeth of the male and female spline-side taper portions 54 , 57 respectively disposed in the male spline portion 47 a and female spline portion 48 a are set to vary in such a manner that they increase gradually in the mutually different directions with respect to the axial direction of the wheel-driving bearing unit.
  • the male and female spline-side taper portions 54 , 57 can be fitted with each other with a sufficient interference between them, thereby being able to prevent occurrence of the above-mentioned teeth striking sounds while the car is running.
  • the male spline teeth 53 , 53 and female spline teeth of the male and female spline-side taper portions 54 , 57 vary a little in shape accuracy, only the degree of insertion of the spline shaft 17 into the spline hole 14 can be changed and, therefore, without increasing the force necessary to push the spline shaft 17 into the spline hole 14 , the male and female spline-side taper portions 54 , 57 can be fitted with each other with a sufficient interference between them.
  • the boot 63 a disposed on the tripod-type constant velocity joint 60 side is able to apply continuously to the spline shaft 17 an axial force going in a direction to push the spline shaft 17 into the spline hole 14 . Thanks to this, even in case where the male spline teeth 53 , 53 and female spline teeth of the male and female spline-side taper portions 54 , 57 are worn through use for a long period of time, the male and female spline-side taper portions 54 , 57 can be fitted with each other with a sufficient interference between them, thereby being able to prevent occurrence of the above-mentioned teeth striking sounds for a long period of time.
  • the side surfaces of the male spline teeth 53 , 53 and female spline teeth in the middle portions or outer half sections of the male and female spline portions 47 a , 48 a are in part contacted with each other and, in such contacted portions, torque is in part transmitted. This can eliminate a fear that excessively large torque can be applied to the two taper portions 54 , 57 .
  • the male-spline-side taper portion 54 and female-spline-side taper portion 57 in which the widths of the male spline teeth 53 , 53 and female spline teeth vary gradually in the axial direction of the wheel-driving bearing unit.
  • the male and female spline-side taper portions 54 , 57 can also be formed only in one of the male and female spline portions 47 a , 48 a .
  • FIGS. 6 and 7 show a second embodiment of a wheel-driving unit according to the invention, which also corresponds only to claim 1 .
  • a male spline portion 47 a formed in the outer peripheral surface of a spline shaft 17 there is formed a male-spline-side taper portion 54 in which the widths of the male spline teeth (which are formed over the entire axial-direction length of the taper portion 54 ) of the taper portion 54 with respect to the circumferential direction thereof vary gradually in such direction that they increase as they go inwardly in the axial direction of the spline shaft 17 , that is, backwardly in the insertion direction of the spline shaft 17 .
  • a female-spline-side taper portion 57 in which the widths of the female spline teeth (which are formed over the entire axial-direction length of the taper portion 57 ) of the taper portion 57 with respect to the circumferential direction thereof vary gradually in such a manner that they decrease as they go outwardly in the axial direction of the spline shaft 17 , that is, forwardly in the insertion direction of the spline shaft 17 .
  • the two spline portions 47 a , 48 a are engaged with each other in a wedge-like manner over the axial-direction entire length thereof.
  • a securing groove 66 in the outer peripheral surface of the base end portion of the spline shaft 17 , there is formed a securing groove 66 in such a manner that it extends over the entire periphery of the present outer surface. And, an O-ring 67 is secured to the securing groove 66 ; and, the O-ring 67 is elastically compressed between the bottom surface of the securing groove 66 and the inner peripheral surface of a cylindrical surface portion which is formed in the inner end portion of a spline hole 14 opened up in the central portion of a hub 4 a and also which is larger in diameter than the root circle of the securing groove 66 .
  • a cap 50 a is fitted with and fixed to the inner surface of the outer end opening of a cylindrical portion 68 formed in the outer end portion of the hub 4 a .
  • the cap 50 a and O-ring 67 cooperate together in preventing foreign substances from getting into a spline engaged portion 49 b which is composed of the male spline portion 47 a formed in the outer peripheral surface of the spline shaft 17 and the female spline portion 48 a formed in the inner peripheral surface of the spline hole 14 .
  • a retaining ring 69 is bridgingly interposed between a securing groove 32 a , which is formed in the outer peripheral surface of the spline shaft 17 and corresponds to a second engaging portion set forth in the appended claims of the present specification, and a securing stepped portion 35 formed in the peripheral edge portion of the outer end opening of the spline hole 14 and corresponding to a first engaging portion set forth in the appended claims of the present specification.
  • a portion of the retaining ring 69 is quenched to thereby form hardened steel wires and these steel wires are bent worked as shown in detail in FIG.
  • the retaining ring 69 has a circular-truncated-cone shape as a whole. More specifically, the retaining ring 69 is structured in the following manner: the steel wires are used to form a shape in which a plurality of crank shapes are arranged continuously and, after then, the retaining ring 69 is rounded in such a manner that the diameter of the retaining ring 69 in its free state decreases as it goes toward one end side (in FIGS. 6 and 7, the left end side) in the axial direction of the retaining ring 69 .
  • the inside diameter d 69 of the outer end portion (inside diameter end portion) of the retaining ring 69 in its free state is set smaller than the outside diameter D 70 of a securing collar portion 70 which is formed in the outer end portion of the spline shaft 17 and is shifted more outwardly in the axial direction of the spline shaft 17 than the securing groove 32 a (d 69 ⁇ D 70 ).
  • the retaining ring 69 is bridgingly interposed between the securing groove 32 a and securing stepped portion 35 . That is, the retaining ring 69 , in a state where the cap 50 a is not mounted on the inner end portion of the hub 4 a , is passed through the periphery of the securing groove 32 a from the outer end side of the spline shaft 17 , while the axial-direction other end portion (in FIGS.
  • the right end portion) of the retaining ring 69 having a larger diameter is arranged as the head of the retaining ring 69 .
  • the inside diameter d 69 of the inside diameter end portion of the retaining ring 69 in its free state is set smaller than the outside diameter D 70 of the securing collar portion 70 of the spline shaft 17 (d 69 ⁇ D 70 )
  • the diameter of the inside diameter end portion of the retaining ring 69 is elastically spread out by the securing collar portion 70 .
  • the inside diameter end portion of the retaining ring 69 is elastically returned to thereby reduce the diameter of the present inside diameter end portion. And, not only the inside diameter end portion of the retaining ring 69 is engaged with the outer end portion of the securing groove 32 a but also the axial-direction length of the retaining ring 69 is elastically compressed.
  • the retaining ring 69 is bridgingly arranged between the securing groove 32 a and securing stepped portion 35 to thereby prevent the spline shaft 17 from slipping out of the spline hole 14 and, at the same time, the elastic force of the retaining ring 69 is able to continue to apply to the spline shaft 17 an axial force going in a direction (in FIG. 6, in the left direction) to pull the spline shaft 17 into the spline hole 14 .
  • a chamfered portion 71 in the outer peripheral surface of the outer end portion of the securing collar portion 70 formed in the outer end portion of the spline shaft 17 , there is formed a chamfered portion 71 , thereby facilitating the passage of the inside diameter end portion of the retaining ring 69 through the periphery of the securing collar portion 70 .
  • the retaining ring 69 which is made of steel wires; however, instead of the retaining ring 69 , there can also be used a retaining ring consisting of a countersunk spring made of a steel plate or a diaphragm spring.
  • FIGS. 8 to 16 show a third embodiment of a wheel-driving unit according to the invention, which corresponds to the appended claims 1 to 4.
  • the present embodiment is basically similar in structure to the previously described first embodiment of the invention shown in FIGS. 1 - 5 . Therefore, like parts are given the same designations and thus the duplicate description thereof is omitted here.
  • a retaining ring 33 b is secured to a securing groove 32 which is formed in the near-to-outer-end portion of the outer peripheral surface of a spline shaft 17 constituting a drive member 18 b and also which corresponds to a second engaging portion set forth in the appended claims of the present specification.
  • the retaining ring 33 b is contacted with or is disposed near to and opposed to a securing stepped portion 35 b which is formed in the near-to-outer-end portion of the inner peripheral surface of a hub 4 c and corresponds to a first engaging portion set forth in the appended claims of the present specification, thereby preventing the spline shaft 17 from shaking in the axial direction thereof within a spline hole 14 formed in the central portion of the hub 4 c as well as from slipping out of the spline hole 14 .
  • the securing stepped portion 35 b is inclined by an angle ⁇ ( in a direction, where it goes outwardly in the axial direction thereof as it goes toward the outside diameter side (in FIG. 14, toward the upward side), with respect to a virtual plane existing at right angles to the center axis of the hub 4 c .
  • the inclination angle ⁇ can regulate the diameter of the retaining ring 33 b from being reduced even in case where there is applied to the spline shaft 17 a strong force going in a direction to pull the spline shaft 17 out of the spline hole 14 .
  • the retaining ring 33 b receives forces respectively from the securing groove 32 and securing stepped portion 35 b ; however, in case where these two forces balance, the diameter of the retaining ring 33 b is not reduced.
  • the angle ⁇ is regulated in a proper range. Normally, since a steel-to-steel static friction coefficient u is about 0.18, in case where the angle ⁇ when ⁇ is set 0.18 is obtained according to the above-mentioned expression, the angle a is equal to or less than 20.4° . Generally, the angle is empirically obtained in such a manner that the pulling force of the spline shaft 17 can provide 3500N or more; and, normally, it is proper to employ a value in the range of 15-20.
  • the retaining ring 33 b is previously mounted into the securing groove 32 before the spline shaft 17 is inserted into the spline hole 14 .
  • the retaining ring 33 b passes through the interior of the spline hole 14 while reducing its diameter elastically.
  • the diameter of the retaining ring 33 b is elastically returned and, as described above, the retaining ring 33 b can be bridgingly interposed between the securing stepped portion 35 b and securing groove 32 .
  • the positions of these securing stepped portion 35 b and securing groove 32 are set according to the shapes of male spline teeth 53 , 53 constituting the male spline portion 47 a and female spline teeth 72 , 72 constituting the female spline portion 48 a . Therefore, in a state where the retaining ring 33 b is returned elastically, the retaining ring 33 b is interposed with no shaky motion between the securing stepped portion 35 b and securing groove 32 , or, even in case where there exists any shaky motion, the amount of the shaky motion is quite small.
  • the seal lip of a seal ring 52 fitted with the outer surface of the outer peripheral surface of a shoulder portion 51 formed in the base end portion of an outer ring 15 for a constant velocity is contacted with the inner surface of a caulk portion 42 a formed in the inner end portion of the hub 4 c to thereby close a clearance existing between the caulk portion 42 a and outer ring 15 for a constant velocity.
  • the portion of the inner surface of the caulk portion 42 a with which the leading end edge of the seal lip is contacted is formed as a flat surface existing in a direction at right angles to the center axis of the hub 4 c , whereby the present seal lip can be contacted with the inner surface of the caulk portion 42 a in a stable manner.
  • the widths of the male spline teeth 53 , 53 (FIGS. 9 and 10) constituting the male spline portion 47 a formed in the outer peripheral surface of the spline shaft 17 , substantially over the entire length thereof except for incomplete portions 73 respectively formed in the male spline teeth 53 , 53 , are set to vary in such a manner that they gradually increase as they go backwardly in the insertion direction of the spline shaft 17 , that is, inwardly in the axial direction of the spline shaft 17 .
  • the circumferential-direction widths of groove portions 55 , 55 which are formed between the male spline teeth 53 , 53 adjoining each other in the circumferential direction of the spline shaft 17 , decrease gradually as they go toward the inner end side of the groove portions. Therefore, the circumferential-direction side surfaces of the male spline teeth 53 , 53 existing in the axial-direction middle portion of the male spline portion 47 a are inclined with respect to the axial direction by the same angle in the mutually opposite directions.
  • the inclination angle of the side surfaces of the male spline teeth 53 , 53 with respect to the axial direction is set in the range of 0.5-1.5° .
  • the axial-direction two end portions of the male spline portion 47 a are formed as incomplete portions 73 , 73 which are inclined at a relatively large angle in a direction where the diameter-direction heights of the male spline teeth 53 , 53 decrease gradually as they go toward the axial-direction two ends of the male spline teeth 53 , 53 .
  • the widths of female spline teeth 72 , 72 (FIGS. 12 and 13) constituting the female spline portion 48 a formed in the inner peripheral surface of the spline hole 14 , substantially over the entire length of the female spline teeth 72 except for incomplete portions 74 formed in the end portions of the female spline teeth 72 , 72 , are set to vary in such a manner that they gradually decrease as they go backwardly in the insertion direction of the spline shaft 17 , that is, inwardly in the axial direction of the spline hole 14 .
  • the widths of groove portions 75 , 75 which constitute the female spline portion 48 a and exist between the female spline teeth 72 , 72 adjoining each other in the circumferential direction of the hub 4 c , increase gradually as they go toward the inner end side of the groove portions 75 .
  • the female spline portion 48 a and male spline portion 47 a are different from each other in the directions where the widths of the teeth 53 , 72 and groove portions 55 , 75 of the respective spline portions 48 a , 47 a increase with respect to the axial direction.
  • the circumferential-direction both-side surfaces of the female spline teeth 72 , 72 constituting the female spline portion 48 a are inclined with respect to the axial direction by the same angle as in the male spline teeth 53 , 53 which constitute the male spline portion 47 a.
  • the operation to form the above-mentioned female spline portion 48 a and male spline portion 47 a can be carried out in the following manner. Firstly, the diameter dimensions of such circles after formation of the teeth that form the sections of the teeth at right angles to the axes of the teeth and are equal to the section area of the spline hole 14 are found at the respective points in the axial direction of the hub 4 c . And, the hub 4 c is cut to form a blank hole to be worked into the spline hole 14 in such a manner that the blank hole can be equal to the diameter dimensions found at the respective points.
  • the thus-cut-formed blank hole provides a conical-shaped taper hole.
  • a punch which includes on the outer peripheral surface thereof a plurality of projecting strips like male spline teeth the widths of which increase gradually as they go toward the axial-direction inner ends thereof, is pushed into the taper hole, which is to be worked into the spline hole 14 , from the inner end side of the taper hole to thereby form the female spline teeth 72 , 72 by pressing.
  • a conical-shaped taper shaft is previously formed by cutting; and, after then, a die, which includes on the inner peripheral surface thereof a plurality of projecting strips like female spline teeth the widths of which increase gradually as they go toward the axial-direction outer ends thereof, is pushed into the taper shaft, which is to be formed into the spline shaft 17 , from the outer end side of the present taper shaft to thereby form the male spline teeth 53 , 53 by pressing.
  • the male spline portion 47 a is heat treated by high frequency quenching to thereby harden the surface thereof.
  • the female spline portion 48 a is not heat treated but is left unquenched.
  • the reason why the quenching treatment is enforced only on one of the male spline portion 47 a and female spline portion 48 a in this manner is that, as the spline shaft 17 is pushed into the spline hole 14 , the side surfaces of the respective teeth 53 , 57 can be made easy to be closely contacted with each other and, at the same time, when the present wheel-driving bearing unit is in use, the occurrence of cracks in the teeth 53 , 72 of the male and female spline portions 47 a , 48 a can be prevented.
  • the method for forming the securing stepped portion 35 b and securing groove 32 is improved in the following manner: that is, in a state where the spline shaft 17 is inserted into the spline hole 14 to thereby form the spline engaged portion 49 b and also the spline engaged portion 49 b is free from shaky motion (that is, the side surfaces of the male spline teeth 53 , 53 constituting the male spline portion 47 a are closely contacted with the side surfaces of the female spline teeth 72 , 72 constituting the female spline portion 48 a ), the retaining ring 33 b can be bridgingly arranged between the securing stepped portion 35 b and securing groove 32 with no shaky motion, or, even in case where any shaky motion exists, the amount of the shaky motion can be made small. This will be discussed below in more detail with reference to FIGS. 15 and 16.
  • FIG. 15 shows how to form the securing stepped portion 35 b in the inner peripheral surface of the middle portion of the spline hole 14 formed in the hub 4 c .
  • the hub 4 c is positioned and held in the chuck 77 of a lathe which is a working apparatus for forming the securing stepped portion 35 b .
  • the male-side gauge 76 can be produced by fixing a positioning block portion 79 to the base end portion (inner end portion) of a spline shaft portion 78 for gauging.
  • a male spline portion 80 In the outer peripheral surface of the spline shaft portion 78 for gauging.
  • the male spline portion 80 for gauging is formed to be identical in shape and dimension with the male spline portion 47 a formed in the outer peripheral surface of the spline shaft 17 constituting the drive member 18 b .
  • each of spline teeth constituting the male spline portion 80 for gauging is an in volute tooth in which a module is 1. 5 and, in a direction where the tooth thickness (the thickness in the circumferential direction) toward the inner end of the tooth, the inclination angle of the two side surfaces of the respective teeth is set at 1° (the taper angle is set at 2° ) .
  • the male spline portion 47 a varies in shape and dimension within a given allowance, whereas the shape and dimension of the male spline portion 80 for gauging are set as the central values in the allowable range of the shape and dimension of the male spline portion 47 a . Also, the position relationship between the male spline portion 80 for gauging and the base end face (inner end face) 81 of the positioning block portion 79 is regulated strictly as prescribed.
  • the male spline portion 80 for gauging of the male-side gauge 76 is inserted into the female spline portion 48 a formed in the inner peripheral surface of the spline hole 14 of the hub 4 c from the inner-end-side opening of the spline hole 14 .
  • the hub 4 c is assembled to the chuck 77 of a lathe for forming the securing stepped portion 35 b by cutting.
  • a reference cylindrical surface 83 which is formed in the outer peripheral surface of the hub 4 c and on which a member to be braked (a disk rotor or a drum) can be mounted, is held down by the chuck 77 .
  • the chuck 77 is rotated and a tool (not shown) is butted against the inner peripheral surface of a portion of the hub 4 c to thereby form the securing stepped portion 35 b (and finish it).
  • the mounting position of the present tool with respect to the chuck 77 is previously regulated strictly. Therefore, in case where the securing stepped portion 35 is finished with the distance L set at a proper value, the position relationship between the securing stepped portion 35 b and the female spline portion 48 a formed in the inner peripheral surface of the spline hole 14 can be established accurately as designed.
  • the reference cylindrical surface 83 which is used to mount the member to be braked.
  • another cylindrical surface provided that it uses the center axis of the hub 4 a as the center axis thereof and does not interfere with the working operation of the securing stepped portion 35 b .
  • a second reference cylindrical surface 84 which is used to mount the wheels onto the hub 4 a
  • a cylindrical surface 86 a which is used to slidingly contact the leading end edge of the seal lip of the seal ring (FIG.
  • a female-side gauge 87 When mounting the drive member 18 b onto the chuck 77 a of a lathe serving as a working apparatus in order to form the securing groove 32 , there is used a female-side gauge 87 .
  • This female-side gauge 87 is formed as a cylindrical shape as a whole and includes a female spline portion 88 for gauging in the inner peripheral surface thereof.
  • the female spline portion 88 for gauging is formed identical in shape and dimension with the female spline portion 48 a formed in the inner peripheral surface of the spline hole 14 of the hub 4 c .
  • each of spline teeth constituting the female spline portion 88 for gauging is an involute tooth in which a module is 1.5 and, in a direction where the tooth thickness (the thickness in the circumferential direction) going toward the outer end of the tooth increases, the inclination angle of the two side surfaces of the respective teeth is set at 1° (the taper angle is set at 2° ) .
  • the female spline portion 48 a varies in shape and dimension within a given allowable range
  • the shape and dimension of the female spline portion 88 for gauging are set as the central values in the allowable range of the shape and dimension of the female spline portion 49 a .
  • the position relationship between the female spline portion 88 for gauging and the base end face (inner end face) 89 of the female-side gauge 87 is regulated strictly as prescribed.
  • the female spline portion 88 for gauging of the female-side gauge 87 is placed on the male spline portion 47 a formed in the outer peripheral surface of the spline shaft 17 of the drive member 18 b from the leading end (outer end) side of the spline shaft 17 .
  • the drive member 18 b is assembled to the chuck 77 a of a lathe for working the securing groove 32 a by cutting.
  • the mounting position of the present tool with respect to the chuck 77 a is previously regulated strictly. Therefore, in case where the securing groove 32 is finish worked with the distance L′set at a proper value, the position relationship between the securing groove 32 and the male spline portion 47 a formed in the outer peripheral surface of the spline shaft 17 can be set accurately as designed.
  • a reference cylindrical surface 90 formed in the outer peripheral surface of the middle portion of the outer ring 15 for a constant velocity joint.
  • another cylindrical surface provided that it uses the center axis of the hub 4 a as the center axis thereof and does not interfere with the working of the securing groove 32 .
  • the diameter of the retaining ring 33 b is elastically returned.
  • the dimension allowances of the respective parts can be regulated in such a manner that the outside diameter of the retaining ring 33 b , shown in FIG. 14, can be prevented from touching the bottom surface of the securing stepped portion 35 b (the inner peripheral surface of the cylindrical surface portion existing more outwardly than the securing stepped portion 35 b )
  • the axial-direction shaky motion of the spline engaged portion 49 b between the male and female spline portions 47 a , 48 a can be eliminated.
  • the working method employed in the present embodiment may be enforced to thereby reduce the dimension allowance down to a small value and increase the inclination angle a of the securing stepped portion 35 b as much as possible.
  • the value of the inclination angle ⁇ has a limit.
  • the securing stepped portion 35 b is formed on the basis of the female spline portion 48 a , while the securing groove 32 is formed on the basis of the male spline portion 47 a .
  • the securing stepped portion 35 b and securing groove 32 are matched in position to each other and the retaining ring 33 b secured to the securing groove 32 , before it is butted against the bottom of the securing stepped portion 35 b , is held into between the securing groove 32 and the inclined surface of the securing stepped portion 35 b in a wedge-like manner, so that the male and female spline portions 47 a , 48 a can be engaged with no shaky motion between them. Even in case where any shaky motion is generated, the amount of such shaky motion is very small, so that generation of jarring strange sounds due to the shaky motion can be controlled down to a practically negligible level.
  • the interference of the seal lip of the seal ring 52 can be excessively small or excessively large, thereby being unable to obtain the desired seal performance. Therefore, in case where the present embodiment is enforced as well, the shape and dimension accuracy of the male and female spline portions 47 a , 48 a must be secured to a certain degree.
  • the male and female spline portions 47 a , 48 a can be fitted with each other with no shaky motion between them; or even in case where there exists any shaky motion between them, they can be fitted together in a state where the amount of such shaky motion is practically negligible amount.
  • the cost necessary for assembly of the present embodiment can be reduced but also, regardless of the existence of variations in the shapes and dimension accuracy of the male and female spline portions 47 a , 48 a , the occurrence of the above-mentioned teeth striking sounds can be prevented.
  • the side surfaces of the male and female spline teeth 53 , 72 of the male and female spline portions 47 a , 48 a can be contacted with each other over the entire lengths thereof with almost uniform contact surface pressure, there by being able to reduce the maximum contact surface pressure that is applied to these spline teeth 53 , 72 . Therefore, in the case of the present embodiment, the durability of the male and female spline teeth 53 , 72 of the male and female spline portions 47 a , 48 a can be enhanced and, at the same time, the occurrence of the teeth striking sounds can be prevented for a long period of time.
  • the teeth widths of the male and female spline teeth 53 , 72 vary in the axial direction, the teeth widths are quite different between the two ends of the respective spline portions 47 a , 48 a .
  • the lengths of the spline portions 47 a , 48 a are set about 30 mm.
  • the module is set at 1.5 which is larger than the normal value (1.0) of the module.
  • the teeth widths of the two ends of the splines on the pitch circles thereof are respectively 1.829 mm and 2.877 mm, while the difference between them is about 1 mm.
  • FIG. 17 shows a fourth embodiment of a wheel-driving unit according to the invention, similarly corresponding to the appended claims 1 to 4.
  • a recessed groove 92 in such portion of the inner peripheral surface of a hub 4 c that exists in the peripheral portion of a securing stepped portion 35 b , there is formed a recessed groove 92 . Formation of such recessed groove 92 can increase the diameter-direction width of the securing stepped portion 35 b and thus, even in case where the inclination angle ⁇ of the securing stepped portion 35 b is set at the same angle, the axial-direction width of the securing stepped portion 35 b can be set large.
  • a retaining ring 33 b secured to a securing groove 32 can be engaged with the securing stepped portion 35 b with no shaky motion between them.
  • the inside diameter d of the portion of the inner peripheral surface of the hub 4 c that is situated nearer to the outer end portion of the hub 4 c than the recessed groove 92 is set equal to or larger than the diameter of the root circle of the female spline portion 48 a , thereby being able to facilitate the working of the female spline portion 48 a .
  • the remaining structures and operations of the present embodiment are similar to those of the previously described third embodiment. Therefore, the illustration and description of the duplicate portions are omitted here.
  • FIG. 18 shows a fifth embodiment of a wheel-driving unit according to the invention, corresponding to the appended claims 1 and 2.
  • the basic structure of the present embodiment is similar to the second example of the conventional structure previously shown in FIG. 40, or to the second embodiment of the invention previously shown in FIG. 6. Therefore, equivalent parts are given the same designations and the duplicate description thereof is omitted or simplified. Thus, description will be given below mainly of the characteristic portions of the present embodiment.
  • a retaining ring 33 is secured to a securing groove 32 which is formed in the outer peripheral surface of the outer end portion of a spline shaft 17 and also which corresponds to a second engaging portion set forth in the appended claims of the present specification.
  • the circumferential-direction widths of male spline teeth constituting a male spline portion 47 a formed in the outer peripheral surface of the spline shaft 17 are set to vary almost over the entire axial-direction length of the spline shaft 17 in such a manner that they increase as they go inwardly in the axial direction of the spline shaft 17 (that is, backwardly in the insertion direction of the spline shaft 17 ).
  • the circumferential-direction widths of female spline teeth constituting a female spline portion 48 a formed in the outer peripheral surface of the spline hole 14 are set to vary almost over the entire axial-direction length of the spline hole 14 in such a manner that they decrease as they go inwardly in the axial direction thereof.
  • the spline shaft 17 is inserted into the spline hole 14 while the male spline portion 47 a is spline engaged with the female spline portion 48 a , whereby not only the two spline portions 47 a , 48 a are fitted with each other with an interference between them but also the inner end face of the hub 4 a is contacted with the outer surface of an outer ring 15 for a constant velocity joint.
  • a given pre-load is applied to a spline engaged portion 49 b between the spline shaft 17 and spline hole 14 , thereby applying a frictional force to the spline engaged portion 49 b which prevents the spline shaft 17 from shifting in a direction to slip out of the spline hole 14 .
  • the retaining ring 33 secured to the securing groove 32 of the spline shaft 17 is situated more outwardly in the axial direction than the outer surface of the securing stepped portion 35 .
  • the spline shaft 17 shifts in the direction to slip out of the spline hole 14 and the outside-diameter-side half section of the retaining ring 33 secured to the securing groove 32 of the hub 4 a is contacted with the outer surface of the securing stepped portion 35 , the spline shaft 17 can be prevented from shifting further in the direction to slip out of the spline hole 14 .
  • these two male and female spline portions 47 a , 48 a can be continuously engaged with each other with a sufficient interference between them, so that prevention of the occurrence of the above-mentioned teeth striking sounds for a long period of time can be attained with more accuracy.
  • FIGS. 19 and 20 show a sixth embodiment of a wheel-driving unit according to the invention, which corresponds to the appended claims 1 to 4.
  • the basic structure of the present embodiment is similar to the second example of the conventional structure previously shown in FIG. 40, or to the second embodiment of the invention previously shown in FIG. 6, or to the fifth embodiment of the invention previously shown in FIG. 18. Therefore, equivalent parts are given the same designations and the duplicate description thereof is omitted or simplified. Thus, description will be given below mainly of the characteristic portions of the present embodiment.
  • a securing stepped portion 35 which is formed in the inner peripheral surface of a hub 4 a , is disposed in a direction intersecting at right angles to the center axis of the hub 4 a .
  • a retaining ring 33 c which is bridgingly interposed between the securing stepped portion 35 and a securing groove 32 formed in the outer peripheral surface of the leading end portion (outer end portion) of a spline shaft 17 , is formed so as to be elastic in a direction where the diameter thereof can be reduced.
  • the retaining ring 33 c is structured in the following manner: that is, its surface disposed opposed to the securing stepped portion 35 is formed as a flat surface 93 which is parallel to the securing stepped portion 35 ; and, the opposite surface thereof is formed as a conically concave-shaped inclined surface 94 which is inclined by angle ⁇ with respect to the flat surface 93 . Therefore, the thickness of the retaining ring 33 c decreases as it goes toward the inside diameter side thereof.
  • the circumferential-direction widths of male spline teeth constituting a male spline portion 47 a formed in the outer peripheral surface of the spline shaft 17 are set to vary in such a manner that they increase as they go inwardly in the axial direction of the spline shaft 17 .
  • the circumferential-direction widths of female spline teeth constituting a female spline portion 48 a formed in the outer peripheral surface of the spline hole 14 are set to vary in such a manner that they decrease as they go inwardly in the axial direction thereof.
  • the spline shaft 17 is inserted into the spline hole 14 while the male spline portion 47 a is spline engaged with the female spline portion 48 a , whereby, in a state where the two spline portions 47 a , 48 a are fitted with each other with an interference between them, the flat face 93 of the retaining ring 33 c secured to the securing groove 32 of the spline shaft 17 is contacted with the securing stepped portion 35 .
  • the inclination angle ⁇ of the inclined surface 94 is restricted to a value, for example, in the range of 15-20° so that the friction force can exceed a pull-out-direction force applied to the spline shaft 17 ; and, therefore, the inner peripheral edge portion of the retaining ring 33 c can be surely prevented from slipping out of the securing groove 32 .
  • the securing groove 32 is formed on the basis of the male spline portion, and the finish working of the securing stepped portion 35 is executed on the basis of the female spline portion 48 a . Accordingly, as described above, in a state where the two spline portions 47 a , 48 a are fitted with each other with no clearance between them, the flat surface 93 of the retaining ring 33 c secured to the securing groove 32 of the spline shaft 17 can be contacted with the securing stepped portion 35 .
  • a spline engaged portion 49 b composed of the male spline portion 47 a formed in the outer peripheral surface of the spline shaft 17 and the female spline portion 48 a formed in the inner peripheral surface of the spline hole 14 , but also male and female spline teeth constituting the spline engaged portion 49 a can be enhanced in durability.
  • FIGS. 21 - 23 show a seventh embodiment of a wheel-driving unit according to the invention, which corresponds to the appended claim 11.
  • the characteristic point of the present embodiment lies in the structure of a spline engaged portion disposed so as to construct the following four connecting portions in such a manner that they are able to transmit the rotation power: that is, specifically, a connecting portion between the output portion of a differential gear and the input portion of a tripod-type constant velocity joint 60 which is a differential-gear-side constant velocity joint; a connecting portion between the output portion of the tripod-type constant velocity joint 60 and one end portion of a drive shaft 26 ; a connecting portion between the other end portion of the drive shaft 26 and the input portion of a wheel-side constant velocity joint 2 c ; and, a connecting portion between a wheel-side constant velocity joint 2 c and a wheel-supporting bearing unit 1 c .
  • the spline engaged portion 49 b between the spline shaft 17 , which is the output portion of the wheel-side constant velocity joint 2 c , and the spline hole 14 of the hub 4 c constituting the wheel-supporting bearing unit 1 c , the spline engaged portion 49 b , basically, is similar to the previously described third embodiment of the invention shown in FIGS. 8 - 14 .
  • the leading end portion (outer end portion) of the spline shaft 17 similarly to the previously described first example of the conventional structure shown in FIG. 39, there is formed a male screw portion 24 .
  • the spline shaft 17 is strongly drawn into the spline hole 14 . And, when the spline shaft 17 is drawn into the spline hole 14 , unquenched and relatively soft female spline teeth constituting a female spline portion 48 a formed in the inner peripheral surface of the spline hole 14 are elastically deformed to thereby allow the spline shaft 17 to shift outwardly in the axial direction thereof.
  • the torsional deformation length of the spline shaft 17 provides a length ranging from the inner end of the spline engaged portion 49 b to the outer end face of the outer ring 15 for a constant velocity joint, that is, the length L shown in FIG. 22.
  • the mutual rubbing length between the inner end face of the spline engaged portion 49 b and the outer end face of the outer ring 15 for a constant velocity joint is short, which can prevent occurrence of strange sounds caused by the mutual rubbing between these two end faces.
  • the male spline teeth 53 , 53 a constituting the male spline portion 47 b can also be composed of even number of teeth; and, the male spline teeth 53 , 53 the circumferential-direction both-side surfaces of which are inclined, and the male spline teeth 53 a , 53 a the circumferential-direction both-side surfaces of which are not inclined can be arranged alternately with respect to the circumferential direction of the male spline portion 47 b .
  • both of the side surfaces of the female spline teeth constituting the female spline portion 48 a and the side surfaces of the male spline teeth constituting the male spline portion 47 a may not be inclined, but one of them may be inclined.
  • a second spline hole 20 formed in the inner peripheral surface of the inner ring 16 is spline engaged with a male spline portion 27 formed in the outer end portion of its mating member, that is, the drive shaft 26 , whereby torque can be freely transmitted between the inner ring 16 and drive shaft 26 .
  • the output portion of the tripod-type constant velocity joint 60 is formed as a boss portion 95 ; and, as shown in FIGS. 21 and 23, a spline hole 96 formed in the inner peripheral surface of the boss portion 95 is spline engaged with a male spline portion 97 formed in the inner end portion of the drive shaft 26 which is a mating member of the joint 60 , whereby the boss portion 95 can be connected to the drive shaft 26 in such a manner that torque can be transmitted between them.
  • At least one of the circumferential-direction both-side surfaces of female spline teeth constituting a female spline portion formed in the inner peripheral surface of the spline hole 96 and the circumferential-direction both-side surfaces of male spline teeth constituting the male spline portion 97 are inclined.
  • the outer end face of the boss portion. 95 is contacted with or is disposed adjacent and opposed to a stepped portion 135 a formed in the near-to-inner-end portion of the outer peripheral surface of the drive shaft 26 .
  • a retaining ring 137 is secured to a securing groove 136 formed in the inner end portion of the drive shaft 26 .
  • the operation to spline engage the male spline portion 97 of the inner end portion of the drive shaft 26 with the spline hole 96 is carried out by a manufacturer who assembles a constant velocity joint, using a machine. Therefore, even in case where the force necessary for pressure insertion of the inner-end-side male spline portion 97 into the second spline hole 96 increases to some degree, the constant velocity joint can be assembled positively.
  • a connecting shaft 102 As the input portion of the tripod-type constant velocity joint 60 , there is used a connecting shaft 102 ; and, as shown in FIGS. 21 and 23, a male spline portion 98 formed in the outer peripheral surface of the connecting shaft 102 is spline engaged with a spline hole 101 formed in the central portion of an output gear 100 of a differential gear 99 which is a mating member of the connecting shaft 102 , whereby the connecting shaft 102 can be connected to the output gear 100 in such a manner that torque can be transmitted between them.
  • a retaining ring 140 is bridgingly interposed between a securing groove 138 formed in the inner peripheral surface of the output gear 100 and a securing groove 139 formed in the outer peripheral surface of the connecting shaft 102 , thereby preventing the two members 102 , 100 from being separated from each other.
  • FIGS. 25 and 26 show an eighth embodiment of a wheel-driving unit according to the invention, which corresponds to the appended claim 6 .
  • the both-side surfaces of the male and female spline teeth are inclined in the axial direction, while the angle of such inclination is set in consideration of not only the axial-direction positioning accuracy between the spline shaft 17 and spline hole 14 but also the workability of the male and female spline teeth.
  • the positioning accuracy can be enhanced, which can facilitate the arrangement of the retaining ring 33 , 33 b , 33 c between the first engaging portion such as the securing stepped portion 35 , 35 a , 35 b and the second engaging portion such as the securing groove 32 , 32 a .
  • the inclination angle is large, it is difficult to form the male and female spline teeth by pressing.
  • the degree of freedom of the inclination angle can be enhanced but, when the working cost is taken into account, it is preferred that the male and female spline teeth are worked by pressing.
  • the inclination angle may be set in the range of 0.75-1.25° (in the case of a taper angle, which is an angle formed between the both-side surfaces of the male and female spline teeth, it may be set in the range of 1.5-2.5° ).
  • the axial-direction length of the spline shaft 17 and spline hole 14 is set in consideration of not only the durability thereof but also the workability of the male and female spline teeth. That is, as the present axial-direction length increases, in the torque transmission between the spline shaft 17 and spline hole 14 , there can be reduced the surface pressure that is applied to the contact portion between the side surfaces of the male and female spline teeth, thereby being able to facilitate the securing of the durability of the spline shaft 17 and spline hole 14 .
  • the axial-direction length may be set in the range of 20-35 mm.
  • the module of the spline shaft 17 and spline hole 14 is set in the range of 1.25-1.75 to thereby prevent the thicknesses of the male and female spline teeth from differing excessively in the axial-direction two ends thereof.
  • a taper shaft 104 is formed by cutting the outer end portion of a blank member 103 constituting the drive member 18 b using a lathe.
  • This taper shaft 104 has a truncated cone shape in which the outside diameter d 1 , of the inner end portion (in FIG. 25, the upper end portion) thereof is larger than the outside diameter d 2 of the outer end portion (in FIG. 25, the lower end portion) thereof (that is, d 1 >d 2 ) .
  • the operation to decide these outside diameters d 1 , d 2 is executed in the following manner.
  • the diameter dimensions of circles which not only form the sections of the taper shaft 104 at right angles to the spline shaft 17 after the male spline teeth are (assumed to be) formed in the male spline portion 47 a but also are equal in section area to the spline shaft 17 , are found in the axial-direction two end portions of the taper shaft 104 ; and, the values of the thus found diameter dimensions are considered as the above outside diameters d 1 , d 2 .
  • the blank member 103 including the thus structured taper shaft 104 in a state where a portion thereof to be formed into an outer ring 15 for a constant velocity joint is gripped by a pushing jig 105 , is disposed opposed to a die 106 which is used to form the male spline portion 47 a.
  • This die 106 is made of sintered high speed steel which is produced by sintering the ultra fine particles of carbide tissues according to a powder metallurgy method; and, the die 106 includes a working hole 107 .
  • the working hole 107 In the inner peripheral surface of the working hole 107 , there are formed a plurality of projecting strips such as female spline teeth the widths of which vary in such a manner that they increase gradually as they go toward the axial-direction outer ends thereof.
  • the inside diameter of the working hole 107 except for the chamfered portions thereof that are formed in the two-end openings thereof, unvary with respect to the axial direction thereof.
  • each of the projecting strips is formed as an involute tooth.
  • a hard film made of TiC or TiN is coated on the inner peripheral surface of each projecting strip including the front surface thereof according to a formed evaporation method using electronic beam evaporation, that is, according to an ARE (Activated Reactive Evaporation) method, thereby enhancing the wear resistance of the present inner peripheral surface.
  • a blank hole 108 Prior to formation of the spline hole 14 , in such portion of the central portion of the hub 4 c as to be worked for formation of the spline portion 14 , there is formed a blank hole 108 , namely, a conically-cylindrical-shaped taper hole in which the inside diameter of the inner end (in FIG. 26, the upper end) side thereof is larger than the inside diameter of the outer end (in FIG. 26, the lower end) side thereof.
  • the manner of finding the inside diameter of the blank hole 108 is similar to the taper shaft 104 for the above-mentioned blank member 103 , except that, in the case of the blank hole 108 , the inside diameter is found and, in the case of the blank member 103 , the outside diameter is found.
  • the punch 111 is made of sintered high speed steel which is similar to the die 106 .
  • a plurality of projecting strips such as male spline teeth the widths of which vary so as to increase gradually as they go toward the axial-direction inner ends thereof.
  • the outside diameter of the punch 111 does not vary in the axial direction thereof, except for the chamfered portions formed in the two end portions thereof.
  • the section shape of each of the projecting strips is an involute tooth.
  • outer peripheral surfaces of the respective projecting strips including the front surfaces thereof are coated with hard thick films formed of TiC or TiN, so that the present outer peripheral surfaces are enhanced in wear resistance.
  • the reason why only the male spline portion 47 a is quenched is that, as the spline shaft 17 is pushed into the spline hole 14 , the side surfaces of the male and female spline teeth can be closely contacted with each other more easily and, when the present embodiment is in use, the teeth of the male and female spline portions 47 a , 48 a can be prevented from being cracked.
  • a circular ring 141 which is fitted with the outside of the cylindrical surface of the inner end side of the hub 4 c , is used to prevent the hub 4 c from expanding outwardly in the diameter direction thereof during the working of the female spline portion 48 a .
  • the circular ring 141 is fitted only with the inner end side of the hub 4 c ; however, preferably, a circular ring having such an inner peripheral surface shape as to be able to hold the outer peripheral surface of the hub 4 c may be fitted with the outer surface of the hub 4 c over the entire length of the portion of the hub 4 c where the female spline portion 48 a is to be formed.
  • a constant velocity joint 2 c incorporating therein the drive member 18 b with the above formed spline shaft 17 and a wheel-supporting bearing unit 1 c incorporating therein the hub 4 c with the above formed spline hole 14 are connected to each other, similarly, for example, to the previously described third embodiment of the invention shown in FIGS. 8 - 14 .
  • the present embodiment as well, not only it is possible to prevent occurrence of the above-mentioned teeth striking sounds while the car is running, but also the durability of the spline teeth of the male and female spline portions 47 a , 48 a can be enhanced.
  • FIGS. 27 - 29 show a ninth embodiment of a wheel-driving unit according to the invention, which corresponds to the appended claims 1, 8, 9.
  • the male and female spline portions 47 a , 48 a can be prevented from shifting in the axial direction thereof with respect to each other, that is, the spline engaged portion 49 b can be prevented against shaky motion.
  • the spline engaged portion 49 b can be prevented against shaky motion.
  • the dimensions and shapes of the composing parts thereof must be worked with high accuracy, for example, in the above-mentioned manner as shown in FIGS. 15 and 16.
  • the working accuracy is poor, in a state where the wheel-supporting bearing unit 1 c and constant velocity joint 2 c are connected together, as in the previously described FIG. 14, it is difficult to bring the incomplete-ring-shaped retaining ring 33 b secured to the securing groove 32 formed in the constant velocity joint 2 c into contact with the diameter-direction middle portion of the securing stepped portion 35 b formed in the wheel-supporting bearing unit 1 c.
  • the securing stepped portion 35 b is inclined by the angle ⁇ with respect to a virtual plane existing at right angles to the center axis of the hub 4 c .
  • the retaining ring 33 b in case where, in a state where the side surfaces of the male and female spline teeth of the male and female spline portions 47 a , 48 a are closely contacted with each other, due to the existence of the inclination angle a , the retaining ring 33 b , as shown in FIG. 14, bites into between the securing stepped portion 35 b and the inner surface of the securing groove 32 in a wedge-like manner, the above-mentioned axial-direction shifting can be prevented.
  • part of the retaining ring 33 b in order for the retaining ring 33 b to be able to positively connect together the wheel-supporting bearing unit 1 c and constant velocity joint 2 c , as shown by a chained line in FIG. 30, part of the retaining ring 33 b must be positively contacted not with the inner peripheral edge of the securing stepped portion 35 b but with the portion of the securing stepped portion 35 b that is situated more outwardly in the diameter direction thereof than the present inner peripheral edge.
  • the diameter of the retaining ring 33 b In the case of the inclination angle ⁇ being increased, there is a limit to the size of the diameter of the retaining ring 33 b : that is, even when there is applied a strong force going in a direction to pull the spline shaft 17 out of the spline hole 14 , in order to be able to prevent the engagement between the retaining ring 33 b and securing stepped portion 35 b from being removed and thus to prevent the spline shaft 17 from slipping out of the spline hole 14 , the diameter of the retaining ring 33 b must be regulated in such a manner that it is prevented from being reduced. For this reason, the angle ⁇ , as described above, is generally set at a value in the range of 15-20° .
  • the axial-direction two side edges of the retaining ring 33 b must be contacted with not only the side surface of the securing groove 32 but also the securing stepped portion 35 b . Therefore, to increase the width dimension W 35b simply is not sufficient and thus it is necessary to increase the diameter-direction dimension D of the portion where the male and female spline portions 47 a and 48 a are spline engaged with each other.
  • the allowable value ⁇ L of the error in the axial-direction position relationship between the hub 4 c and spline shaft 17 is approximately D ⁇ sin ⁇ or less ( ⁇ L ⁇ D ⁇ sin ⁇ ) ) .
  • D is difficult, not only because there is a limit to the dimension of the unit but also because it gives rise to a great increase in the manufacturing costs of the male and female spline portions 47 a and 48 a.
  • This value is much greater than 0.31 mm that is the value of the ⁇ L, which shows that it is difficult to prevent the shaky motion in the axial direction.
  • the working accuracy may be enhanced so as to reduce the position shift amount, or, the outside and inside engaging portions may be worked according to the method previously described with reference to FIGS. 15 and 16 to thereby reduce the position shift amount down to 0.31 mm or less.
  • the retaining ring in a state where the side surfaces of the male and female spline teeth are contacted with each other, the retaining ring can be engaged with its mating surface in a normal state, whereby the hub and spline shaft can be assembled in such a manner that occurrence of shaky motion in the axial direction thereof is prevented.
  • the male spline teeth 53 of a male spline portion 47 a are formed as taper spline teeth the circumferential-direction widths of which increase as they go toward the inner end sides thereof; and, the female spline teeth 72 of a female spline portion 48 a (see FIG. 29), as previously shown in FIGS. 12 and 13, are formed as taper spline teeth the circumferential-direction widths of which increase as they go toward the outer end sides thereof.
  • the male and female spline portions 47 a and 48 a can be engaged with each other with no circumferential-direction shaky motion between them as the spline shaft 17 is inserted into the spline hole 14 from the inner end opening thereof.
  • the diameter-direction width dimension W 35c , of the securing stepped portion 35 c formed in the middle portion of the inner peripheral surface of the hub 4 c is set larger than the previously described third embodiment (W 35c >W 35b ) .
  • a retaining ring 112 to be bridgingly interposed between the securing stepped portion 35 c and securing groove 32 formed in the outer peripheral surface of the leading end portion of the spline shaft 17 constituting a drive member 18 b there is used a retaining ring the circumferential-direction shape of which, as shown in FIG. 28, is a corrugated shape.
  • a wire member made of spring steel which is used to form the retaining ring 112 , is alternately curved in the mutually opposite directions at a equal pitch with respect to the diameter direction thereof in a completed state thereof, and is further bent formed into an incomplete circular ring shape, thereby forming a retaining ring 112 having such a shape as shown in FIG. 28.
  • the retaining ring 112 includes, in a plurality of circumferential-direction portions of the inner peripheral edge portion thereof, a plurality of inwardly projecting portions 113 , 113 projecting more inwardly in the diameter direction thereof than the remaining portions of the present inner peripheral edge portion and, in a plurality of circumferential-direction portions of the outer peripheral edge portion thereof, a plurality of outwardly projecting portions 114 , 114 projecting more outwardly in the diameter direction thereof than the remaining portions of the present outer peripheral edge portion.
  • the retaining ring 112 has a shape which projects alternately on the outside diameter side and on the inside diameter side of a pitch circle shown by a chained line 112 b in FIG. 28, with the chained line as the boundary between them.
  • the diameter-direction positions of the outer peripheral edges of the outwardly projecting portions 114 , 114 and the diameter-direction positions of the inner peripheral edges of the inwardly projecting portions 113 , 113 are both much larger than the diameter of the section of the wire member for forming the retaining ring 112 .
  • the retaining ring 112 can be positively arranged between the securing stepped portion 35 c and securing groove 32 . Thanks to this, even in case where the dimensions and shapes of the composing parts are not worked with high accuracy, the shaky motion of the spline engaged portion 49 b can be prevented. Description will be given below of this point with reference to FIG. 29.
  • a state shown by the solid lines is a state in which, in the range that can effectively prevent the spline shaft 17 from slipping out of the spline hole 14 , the diameter of the retaining ring 112 is smallest.
  • the side surfaces of the outwardly projecting portions 114 are contacted with the slightly-near-to-outside-diameter portion of the inner peripheral edge portion (that is, the portion that is situated nearer a little to the outside diameter side than the inner peripheral edge) of the securing stepped portion 35 c .
  • a state shown by the chained lines is a state in which, in the range that can effectively prevent the spline shaft 17 from slipping out of the spline hole 14 , the diameter of the retaining ring 112 is largest.
  • the side surfaces of the inwardly projecting portions 113 are contacted with the slightly-near-to-inside-diameter portion of the opening peripheral edge portion (that is, the portion that is situated nearer a little to the inside diameter side than the inner peripheral edge) of the securing groove 32 .
  • the spline engaged portion 49 b between the spline hole 14 and spline shaft 17 can be prevented against shaky motion.
  • the diameter-direction difference ⁇ D between the position shown by the solid line in FIG. 29 and the position shown by the chained line in FIG. 29 is much larger than the previously described third embodiment of the invention.
  • the diameter-direction width dimension W 35c , of the securing stepped portion 35 c can be increased, which makes it possible to increase the axial-direction tolerance ⁇ L′ between the securing stepped portion 35 c and securing groove 32 that can be obtained from ⁇ D ⁇ sin ⁇ .
  • To be able to increase the tolerance ⁇ L′ means that, even in case where the dimensions and shapes of the composing parts are not worked with high accuracy, the shaky motion of the spline engaged portion 49 b can be prevented.
  • the above-structured wheel-driving bearing unit according to the present embodiment is incorporated into the car as a wheel-driving unit as shown in FIG. 31. That is, the output portion of a tripod-type constant velocity joint 60 , which is a differential-side constant velocity joint, is combined with the input portion of a wheel-side constant velocity joint 2 c through a drive shaft 26 .
  • FIG. 33 shows a tenth embodiment of a wheel-driving unit according to the invention, which also corresponds to the appended claims 1, 8 and 9.
  • the present embodiment there is shown an embodiment in which the invention is applied based on the second example of the conventional structure previously shown in FIG. 40. Accordingly, description will be given below of the portions of the present embodiment that are different from the structure shown in FIG. 40.
  • the spline teeth of male and female spline portions 47 a and 48 a constituting the spline engaged portion 49 b between the spline hole 14 and spline shaft 17 are composed of taper spline teeth; and, the spline shaft 17 and spline hole 14 are structured such that the former can be inserted into the latter with a light force and thus, in the leading end face of the spline shaft 17 , there is not formed such securing portion 31 as in the conventional structure shown in FIG. 40.
  • a cap 50 a is disposed on the outer end portion of a hub 4 a to thereby close the outer end opening of the hub 4 a and a member to be interposed between the inner end face of the hub 4 a and the outer end face of an outer ring for a constant velocity joint is changed from the elastic ring 34 (FIG. 40) to an O-ring 117 . And, the O-ring 117 and cap 50 a cooperate together in preventing foreign substances such as rainwater from getting into the spline engaged portion 49 b.
  • a securing groove 32 in such a manner that it extends over the entire periphery of such portion. And, between the securing stepped portion 35 c and securing groove 32 , there is bridgingly arranged such a retaining ring 112 as shown in FIG. 28 or such a retaining ring 112 a as shown in FIG. 32.
  • the basic structure of the wheel-driving bearing unit is similar to the second example of the conventional structure previously shown in FIG. 40; and, the structure of the portion for preventing the spline shaft 17 from slipping out of the spline hole 14 is similar to the previously described ninth embodiment of the invention. Therefore, equivalent parts are given the same designations and thus the duplicate description thereof is omitted here.
  • FIG. 34 shows an eleventh embodiment of a wheel-driving unit according to the invention, which corresponds to the appended claims 1, 8 and 10.
  • the axial-direction middle portion of a hub 4 b is closed by a partition wall portion 119 to thereby not only secure the strength of the hub 4 b but also prevent foreign substances such as rainwater from getting into the inner end side of the hub 4 b from the outer end side thereof.
  • a cap 50 b is disposed on the outer end portion of the hub 4 b to thereby prevent mud and small stones from getting into a recessed portion 120 existing in the outer end portion of the hub 4 b.
  • an outside securing groove 121 in the inner peripheral surface of the outer end portion of an outer ring 15 a for a constant velocity joint which constitutes a wheel-side constant velocity joint 2 b and corresponds to part of a drive member set forth in the appended claims of the present specification, there is formed an outside securing groove 121 .
  • This outside securing groove 121 is similar in shape to the outside securing groove 45 employed in the structure shown in FIG. 41.
  • a cylindrical surface portion 122 which is smaller in diameter than the root circle of an outside-diameter-side male spline portion 40 formed in the outer peripheral surface of the intermediate seat 38 ; and, the cylindrical surface portion 122 is continuously connected to the outer end portion of the outside-diameter-side male spline portion 40 through a securing stepped portion 35 d . And, between the securing stepped portion 35 d and outside securing groove 121 , there is bridgingly interposed such a retaining ring 112 as shown in FIG. 28 or such a retaining ring 112 a as shown in FIG. 32.
  • the basic structure of a wheel-driving bearing unit is similar to the third example of the conventional structure previously shown in FIG. 41, while the structure of the portion for preventing the outer ring 15 a for a constant velocity joint and intermediate seat 38 against separation from each other as well as the structure of the spline engaged portion 49 a are similar to the previously described ninth and tenth embodiments of the invention. Therefore, equivalent parts are given the same designations and thus the duplicate description thereof is omitted here.
  • a portion corresponding to the intermediate seat 38 can also be formed integrally with an inner ring 5 . Also, a portion, which is formed in the inner peripheral surface of the outer ring 15 a for a constant velocity joint and corresponds to a second engaging portion set forth in the appended claims of the present specification, as in FIG.
  • 35 showing a twelfth embodiment of a wheel-driving unit according to the invention can be formed as an outside securing groove 121 a the axial-direction-outside inner surface of which is formed as an inclined surface; and, a portion, which is formed in the outer peripheral surface of the outer end portion of the intermediate seat 38 and corresponds to a first engaging portion set forth in the appended claims of the present specification, can be formed as an inside securing groove 123 .
  • FIGS. 36 - 38 show a thirteenth embodiment of a wheel-driving unit according to the invention, which corresponds to the appended claims 1, 5, 6 and 7.
  • the circumferential-direction widths of male spline teeth constituting a male spline portion 47 a press formed in the outer peripheral surface of a spline shaft 17 vary so as to increase as they go inwardly in the axial direction thereof.
  • the circumferential-direction widths of female spline teeth constituting a female spline portion 48 a press formed in the inner peripheral surface of a spline hole 14 vary so as to decrease as they go inwardly in the axial direction thereof. And, in a state where the spline shaft 17 is inserted into the spline hole 14 while the male spline portion 47 a is spline engaged with the female spline portion 48 a , the circumferential-direction both-side surfaces of the male spline teeth are respectively contacted with the circumferential-direction both-side surfaces of the female spline teeth with no clearance between them.
  • the base end portion of the spline shaft 17 there is formed a cylindrical portion 124 which is larger in diameter than the root circle of the complete spline portion of the male spline portion 47 a . That is, the base end portion of the spline shaft 17 (the taper shaft 104 of the blank member 103 shown in FIG. 25) prior to formation of the male spline portion 47 a provides a shape which can be obtained by extending the portion for formation of the male spline portion 47 a as it is (that is, without reducing the diameter thereof) .
  • the outside diameter of the cylindrical portion 124 is smaller than the diameter of the addendum circle of the male spline portion 47 a and is larger than the diameter of the above-mentioned root circle.
  • the base end portion of the spline shaft 17 is hard to buckle and deform, thereby being able to enhance the yield of the drive member 18 b including the male spline portion 47 a.
  • the press working operation for forming the male spline portion 47 a is carried out in two separate steps. Firstly, in the first step, in the outer peripheral surface of a taper shaft of a blank member, there are formed parallel male spline teeth the circumferential-direction both-side surfaces of which are parallel to each other with respect to the axial direction of the taper shaft. Next, in the second step, the parallel male spline teeth are formed as taper male spline teeth the circumferential-direction widths of which decrease as they go toward the outer end portions thereof.
  • a flat surface 126 in the central portion of the deep surface of the outer ring 15 for a constant velocity joint disposed on the inner end portion of the drive member 18 b , there is formed a flat surface 126 .
  • the flat surface 126 can be pressed freely.
  • the flat surface 126 is worked by turning into a plane exactly at right angles to the center axis of the blank member so that, when the blank member is pushed into the die, the blank member can be prevented against shaky motion.
  • the respective parts thereof are finished to their respective desired shapes and properties through the steps of: [forging the blank member]; [turning the flat surface 126 (the outer peripheral surface of the taper shaft is left as it is forged but is not turned)]; [pressing the male spline shaft 47 a]; [turning the respective parts except for the flat surface 126 ]; and, [grinding the outside engaging grooves 19 , 19 formed in the inner peripheral surface of the outer ring 15 for a constant velocity joint and the inner surface of the retainer].
  • the inner end face 127 of the outer ring 15 for a constant velocity joint is strongly pushed by the push-in jig 105 (see FIG. 25).
  • the inner end portion of the outer ring 15 for a constant velocity joint is small in thickness, in case where a large load is applied to the outer ring 15 by the push-in jig 105 , there is a possibility that the inner end portion of the outer ring 15 can be plastically deformed.
  • the thickness of the inner end portion of the outer ring 15 provides a limit to the workability of the male spline portion 47 a , thereby raising a possibility that the drive member 18 b according to the eighth embodiment cannot be reduced in weight to a sufficient degree.
  • the retaining ring 33 b for connecting them together is structured such that the diameter thereof can be reduced easily. That is, in the case of the present embodiment, the retaining ring 30 a is bridgingly interposed between an outside securing groove 121 b formed in the near-to-outer-end portion of the inner peripheral surface of the spline hole 14 and an inside securing groove 123 a formed in the near-to-outer-end portion of the spline shaft 17 .
  • the axial-direction position relationship between the two members 1 c , 2 c can be determined just uniquely.
  • the operation for such arrangement of the retaining ring 33 b between the two securing grooves 121 b , 123 a similarly to the previously described respective embodiments, can be carried out automatically; however, special consideration must be given in order to be able to reduce the diameter of the retaining ring 33 b for dismantlement.
  • recessed grooves 128 which are respectively recessed outwardly in the diameter direction of the spline hole 14 . Accordingly, when reducing the diameter of the retaining ring 33 b for dismantlement, projecting pieces 130 , 130 of a diameter reducing jig 129 shown in FIG. 37 are respectively inserted into their associated recessed grooves 128 .
  • guide inclined surfaces 131 , 131 which are inclined in a direction to go outwardly in the diameter direction as they go toward the leading end portions thereof.
  • recessed grooves 133 , 133 which extend along the axial direction thereof and are used to prevent interference with the male spline teeth existing in the outer peripheral surface of the spline shaft 17 .
  • the circumferential-direction width W 130 of the projecting pieces 130 , 130 is set larger than the circumferential-direction width W 134 of the discontinuous portion 134 (in a state where the retaining ring 33 b is mounted on the outside securing groove 121 b ) of the retaining ring 33 b ( W 130 >W 134 ) .
  • the reason for this is that, in case where, as shown in FIG.
  • W 134 is smaller than W 130 , any one of the projecting pieces 130 can be inserted into the discontinuous portion 134 ; and, as a result of this, there arises a possibility that, even in case where the projecting pieces 130 , 130 are pushed further into their respective recessed grooves 128 , the diameter of the retaining ring 33 b cannot be reduced.
  • the present invention Since the present invention is structured and operates in the above-mentioned manner, it not only can facilitate the assembling operation to thereby reduce the manufacturing cost thereof but also can prevent generation of teeth striking sounds which jar the nerves of an occupant.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Rolling Contact Bearings (AREA)
US10/296,126 2000-05-31 2001-05-24 Wheel driving unit and method of manufacturing the same Abandoned US20030146591A1 (en)

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US20030218309A1 (en) * 2002-05-23 2003-11-27 Visteon Global Technologies, Inc. Vehicle wheel end having integrated knuckle and outer race
FR2877702A1 (fr) * 2004-11-08 2006-05-12 Renault Sas Vis entraineur joint de oldham pour pompe a vide
DE102005035706A1 (de) * 2005-07-27 2007-02-08 Gkn Driveline Deutschland Gmbh Längsvariable Verzahnung
WO2007079764A1 (fr) * 2005-12-29 2007-07-19 Gkn Driveline International Gmbh Articulation tournante synchrone avec précontrainte interne
GB2446156A (en) * 2007-01-31 2008-08-06 Gm Global Tech Operations Inc Splined connection in all wheel drive system
US20100021102A1 (en) * 2006-12-27 2010-01-28 Yoshikazu Fukumura Wheel bearing device
ES2340568A1 (es) * 2006-02-22 2010-06-04 Shaft-Form-Engineering Gmbh Junta homocinetica.
US8714573B2 (en) * 2012-09-18 2014-05-06 Jtekt Corporation Vehicle bearing apparatus
US20140239706A1 (en) * 2007-03-22 2014-08-28 Ntn Corporation Bearing device for a wheel
US20160160925A1 (en) * 2014-12-04 2016-06-09 Schaeffler Technologies AG & Co. KG Rolling bearing assembly with carbon fiber seal
US9670963B2 (en) 2013-12-17 2017-06-06 Dana Automotive Systems Group, Llc Constant velocity joint
US10086649B2 (en) 2013-03-12 2018-10-02 Ntn Corporation Bearing device for wheel
CN111469972A (zh) * 2017-05-30 2020-07-31 株式会社岛野 自行车后链轮组件
US11053985B2 (en) 2016-02-10 2021-07-06 Dana Automotive Systems Group, Llc Direct pinion mount constant velocity joint
US11156252B2 (en) 2016-05-10 2021-10-26 Dana Automotive Systems Group, Llc Boot assembly for a constant velocity joint
US11319998B2 (en) 2017-03-31 2022-05-03 Dana Automotive Systems Group, Llc Constant velocity joint assembly
US11655858B2 (en) * 2017-12-27 2023-05-23 Nio Technology (Anhui) Co., Ltd. Housing drive connection for a constant velocity joint

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JP5202887B2 (ja) * 2007-06-29 2013-06-05 Ｎｔｎ株式会社 ステアリング用ジョイント
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JP2010210005A (ja) * 2009-03-10 2010-09-24 Aisin Seiki Co Ltd 液圧式クラッチレリーズ装置
JP2010242781A (ja) * 2009-04-01 2010-10-28 Ntn Corp 車輪用軸受装置の組立方法
DE102011104058B4 (de) * 2011-06-11 2023-11-02 Volkswagen Aktiengesellschaft Verbindungsanordnung zwischen einer Gelenkwelle und einem Getriebe
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JP6717688B2 (ja) * 2016-06-30 2020-07-01 日立オートモティブシステムズ株式会社 プロペラシャフト
JP6744419B2 (ja) * 2016-10-11 2020-08-19 日立オートモティブシステムズ株式会社 プロペラシャフト及びその製造方法
JP7441000B2 (ja) * 2018-11-05 2024-02-29 日立Astemo株式会社 プロペラシャフトおよびその製造方法
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Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6736418B2 (en) * 2002-05-23 2004-05-18 Visteon Global Technologies, Inc. Vehicle wheel end having integrated knuckle and outer race
US20030218309A1 (en) * 2002-05-23 2003-11-27 Visteon Global Technologies, Inc. Vehicle wheel end having integrated knuckle and outer race
FR2877702A1 (fr) * 2004-11-08 2006-05-12 Renault Sas Vis entraineur joint de oldham pour pompe a vide
DE102005035706A1 (de) * 2005-07-27 2007-02-08 Gkn Driveline Deutschland Gmbh Längsvariable Verzahnung
DE102005035706B4 (de) * 2005-07-27 2008-01-31 Gkn Driveline Deutschland Gmbh Längsvariable Verzahnung
WO2007079764A1 (fr) * 2005-12-29 2007-07-19 Gkn Driveline International Gmbh Articulation tournante synchrone avec précontrainte interne
ES2340568A1 (es) * 2006-02-22 2010-06-04 Shaft-Form-Engineering Gmbh Junta homocinetica.
US8382378B2 (en) 2006-12-27 2013-02-26 Ntn Corporation Wheel bearing device
US20100021102A1 (en) * 2006-12-27 2010-01-28 Yoshikazu Fukumura Wheel bearing device
US8434582B2 (en) 2007-01-31 2013-05-07 GM Global Technology Operations LLC All wheel drive system
GB2446156B (en) * 2007-01-31 2008-12-24 Gm Global Tech Operations Inc All wheel drive system
GB2446156A (en) * 2007-01-31 2008-08-06 Gm Global Tech Operations Inc Splined connection in all wheel drive system
US20100232874A1 (en) * 2007-01-31 2010-09-16 Gm Global Technology Operations, Inc. All wheel drive system
US9511629B2 (en) * 2007-03-22 2016-12-06 Ntn Corporation Bearing device for a wheel
US20140239706A1 (en) * 2007-03-22 2014-08-28 Ntn Corporation Bearing device for a wheel
US8714573B2 (en) * 2012-09-18 2014-05-06 Jtekt Corporation Vehicle bearing apparatus
US10086649B2 (en) 2013-03-12 2018-10-02 Ntn Corporation Bearing device for wheel
US9670963B2 (en) 2013-12-17 2017-06-06 Dana Automotive Systems Group, Llc Constant velocity joint
US20160160925A1 (en) * 2014-12-04 2016-06-09 Schaeffler Technologies AG & Co. KG Rolling bearing assembly with carbon fiber seal
US11053985B2 (en) 2016-02-10 2021-07-06 Dana Automotive Systems Group, Llc Direct pinion mount constant velocity joint
US11156252B2 (en) 2016-05-10 2021-10-26 Dana Automotive Systems Group, Llc Boot assembly for a constant velocity joint
US11319998B2 (en) 2017-03-31 2022-05-03 Dana Automotive Systems Group, Llc Constant velocity joint assembly
CN111469972A (zh) * 2017-05-30 2020-07-31 株式会社岛野 自行车后链轮组件
US11655858B2 (en) * 2017-12-27 2023-05-23 Nio Technology (Anhui) Co., Ltd. Housing drive connection for a constant velocity joint

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US7104893B2 (en) 2006-09-12
JP2002200902A (ja) 2002-07-16
AU6061701A (en) 2001-12-11
US20050159227A1 (en) 2005-07-21
WO2001092739A1 (fr) 2001-12-06
JP4474774B2 (ja) 2010-06-09

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