JP2000142015A - Axle unit for wheel driving - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a spline aperture and a spline shaft from being subjected to a friction and an abrasion of a spline engaging portion in spite of a thrust load generated at a tripod type constant velocity joint portion during an operation. SOLUTION: A snap ring 35 is stretched between a stepped portion 43 provided in adjacent to a spline aperture 28 and an inner engaging groove 14 provided on a spline shaft 30 and a driving shaft member 29 and a hub 6a are connected. The hub 6a is urged with a force larger than the above thrust load by a core bar 69 made of an elastic material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION A wheel drive axle unit according to the present invention is a so-called fourth-generation hub unit in which a constant velocity joint and a hub unit are disassembled and integrated, and is provided as an independent suspension type suspension. Supported drive wheels: Front wheels of front-wheel drive front-wheel drive vehicles (FR), FR
The rear wheels 4 of a vehicle (front-engine rear-wheel drive vehicle) and RR vehicle (rear-engine rear-wheel drive vehicle) and a 4WD vehicle (four-wheel drive vehicle) are rotatably supported with respect to the suspension device. Along with
It is used to rotationally drive the drive wheels.

[0002]

2. Description of the Related Art In order to rotatably support wheels with respect to a suspension device, various axle units in which an outer wheel and an inner wheel are rotatably combined via rolling elements have been used. or,
In addition to supporting the drive wheels on an independent suspension,
The wheel drive axle unit for rotating this drive wheel, in combination with a constant velocity joint, controls the rotation of the drive shaft regardless of the relative displacement between the differential gear and the drive wheel and the steering angle given to the wheel. It must be transmitted smoothly (with constant velocity) to the wheels. As a so-called fourth-generation hub unit, a wheel drive axle unit that can be configured to be relatively small and lightweight in combination with such a constant velocity joint, see, for example, Japanese Patent Application Laid-Open No. 7-3177.
No. 54, or U.S. Pat. No. 5,674,011 is known.

[0003] FIG. 18 is a diagram of Japanese Patent Application Laid-Open No. 7-3177.
No. 54 discloses a first example of a conventional structure. The outer ring 1 which is supported by the suspension device and does not rotate in the assembled state to the vehicle has an outward flange-shaped mounting portion 2 for supporting the suspension device on the outer peripheral surface, and a double-row outer ring raceway 3 on the inner peripheral surface. , 3 respectively. A hub 6 formed by combining the first element 4 and the second element 5 is arranged inside the outer ring 1. The first element 4 has a mounting flange 7 for supporting the wheel at one end of the outer peripheral surface (near the left end in FIG. 18), and an inner raceway 8 at the other end (near the right end in FIG. 18). Are formed in a cylindrical shape provided respectively. On the other hand, the second element 5 has one end (the left end in FIG. 18) as a cylindrical portion 9 for externally fitting and fixing the first element 4, and the other end (the right end in FIG. 18). Is a housing part 11 which becomes an outer ring of a zeppa type constant velocity joint 10, and an inner ring raceway 8 is provided on an outer peripheral surface of an intermediate part. By providing a plurality of rolling elements 12, 12 between the outer raceways 3, 3 and the inner raceways 8, 8, the hub 6 is rotatable inside the outer race 1. I support it.

An outer locking groove 13 and an inner locking groove 14 are formed at positions where the inner peripheral surface of the first element 4 and the outer peripheral surface of the second element 5 are aligned with each other. The first element 4 is prevented from falling out of the second element 5 by providing the ring 15 in such a manner as to extend over both the locking grooves 13 and 14. Further, an outer peripheral edge of one end face (the left end face in FIG. 18) of the second element 5 and the first element 4
1 between the inner peripheral edge of the step 16 formed on the inner peripheral surface of
7 to fix the first and second elements 4 and 5 together.

Further, between the openings at both ends of the outer ring 1 and the outer peripheral surface of the intermediate portion of the hub 6, a substantially cylindrical cover 18 made of a metal such as a stainless steel plate, and rubber or other elastomer, etc. Annular seal ring 19, 1 made of elastic material
9 are provided. Further, a partition plate portion 20 for closing the inside of the second element 5 is provided inside the intermediate portion of the second element 5. These covers 18, 18, seal rings 19, 19
And the partition plate portion 20 blocks the portion where the plurality of rolling elements 12 and 12 are installed or the portion of the constant velocity joint 10 from the outside, and prevents the grease present in the portion from leaking outside. In addition, it is possible to prevent foreign matters such as rainwater and dust from entering this portion.

The constant velocity joint 10 includes the housing 11, an inner race 21, a retainer 22, and a plurality of balls 23. The inner race 21 is fixed to a distal end of a drive shaft (not shown) which is driven to rotate by a transmission via an engine. On the outer peripheral surface of the inner ring 21, there are six inner engaging grooves 24 having a circular cross section when cut along a virtual plane perpendicular to the center axis of the inner ring 21. They are formed at equal intervals in a direction perpendicular to the circumferential direction. Also, at the position on the inner peripheral surface of the housing portion 11 facing the inner engaging groove 24, six outer engaging grooves 25 also having an arc-shaped cross section are formed in a direction perpendicular to the circumferential direction. Has formed.
The retainer 22 has an arcuate cross section and is formed in an annular shape as a whole.
And the inner peripheral surface of the At six positions in the circumferential direction of the retainer 22, the inner and outer engagement grooves 24, 25 are provided.
The pocket 26 is formed at the position corresponding to
A total of six balls 23 are held inside each pocket 26, one for each. Each of these balls 23
In a state of being held in the respective pockets 26, they can roll freely along the inner and outer engagement grooves 24, 25.

When the wheel drive axle unit configured as described above is assembled to a vehicle, the outer ring 1 is supported on a suspension device by the mounting portion 2, and the drive wheel is fixed to the first element 4 by the mounting flange 7. Further, the tip of a drive shaft (not shown), which is rotationally driven by the engine via a transmission, is spline-engaged with the inside of the inner race 21 constituting the constant velocity joint 10. When the automobile is running, the rotation of the inner wheel 21 is transmitted to the hub 6 including the second element 5 via the plurality of balls 23, and the driving wheels are rotated.

FIG. 19 is a view showing the structure of the above-mentioned US Pat.
11 shows a second example of the conventional structure described in the specification of Japanese Patent No. 11; In the case of the second example of this conventional structure, double-row outer ring raceways 3 are provided on the inner peripheral surface of the outer ring 1 which is not fitted and fixed to the knuckle 40 constituting the suspension and rotates when used. One end of the outer peripheral surface of the hub 6a (near the left end in FIG. 19)
A mounting flange 7 for supporting a wheel is provided at a portion, and a pair of inner rings 5 is provided at a portion near the other end (a portion near the right end in FIG. 19).
Double-row inner raceways 8 and 8 are provided via 0 and 50, respectively. These inner rings 50, 50 are supported and fixed to the main body of the hub 6a by a caulking portion 27 formed by bending the other end of the hub 6a outward in the diameter direction.
A plurality of rolling elements 12, 12 are provided between the outer raceways 3, 3 and the inner raceways 8, 8, respectively, and the hub 6a is rotatable inside the outer race 1. I support it.

A spline hole 28 is provided in the center of the hub 6a. Further, the hub 6a and the drive shaft member 29 are combined to form a wheel drive axle unit. At one end of the drive shaft member 29, a spline shaft 30 that engages with the spline hole 28 is provided. Further, the other end of the drive shaft member 29 is a housing portion 11 serving as an outer ring of a constant velocity joint. Such a drive shaft member 29 and the hub 6a are combined in a state where the spline shaft 30 is inserted into the spline hole 28, and the coupling member 31 made of an elastic material which is unevenly engaged with the two members 29 and 6a. The separation is prevented. It should be noted that encoders 32, 32 made of a magnetic material or a permanent magnet are attached to the coupling member 31 so that the rotational speeds of the two members 29, 6a can be detected.

FIG. 20 shows a utility model registration No. 25733.
No. 25 discloses a third example of the conventional structure. In the case of the third example of the conventional structure, the hub 6b is spline-engaged with the end of the axle 92 exposed from the end of the axle tube 93. The hub 6b is rotatably supported inside the fixed outer ring 1a by rolling elements arranged in multiple rows. Further, a ring-shaped retaining ring 15a is engaged with an engagement groove 94 formed at a portion of the axle 92 protruding from the hub 6b at the tip end of the axle 92 to prevent the hub 6b from coming off the axle 92. are doing.

FIG. 21 is a view showing a structure of a U.S. Pat. No. 4,881,842.
4 shows a fourth example of a conventional structure described in the specification. In the case of the fourth example of this conventional structure, the hubs 6c are rotatably supported by rolling elements arranged in multiple rows inside the outer ring 1b fixed to the knuckle 40. A spline shaft 30 is spline-engaged with a spline hole 28 formed in the center of the hub 6c. At the base end (the right end in FIG. 21) of the spline shaft 30, there is provided a housing portion 11 serving as an outer ring of the constant velocity joint.
On the other hand, the front end surface of the spline shaft 30 (FIG. 21)
The left end surface of the spline shaft 30 has a locking portion 9 for locking a tool for drawing the spline shaft 30 into the spline hole 28.
5 are formed. Then, the retaining ring 1 locked in a locking groove formed in a portion near the front end of the outer peripheral surface of the spline shaft 30.
5b prevents the hub 6c from slipping out of the spline shaft 30. In this state, the hub 6c
The elastic ring 96 is elastically compressed between the housing and the housing portion 11 to prevent the hub 6c from rattling against the spline shaft 30.

Further, FIG.
7 shows a fifth example of a conventional structure described in the specification of Japanese Patent Application Laid-Open No. 7-107. Also in the case of the fifth example of this conventional structure, the hub 6d is rotatably supported by the rolling elements arranged in multiple rows inside the outer ring 1c fixed to the knuckle 40. Hub 6d for this
The inner ring 50 which is fitted on the hub 6 is prevented from moving in the axial direction by a retaining ring 97 locked to the hub 6d. A constant-velocity joint is formed, and the front end of the sleeve 98 (FIG. 2) is spline-engaged with the inner end (right end in FIG. 22) of the hub 6d.
2 (left end portion) covers the retaining ring 97 so that the retaining ring 97 does not come off the hub 6d. Further, a retaining ring 15c is extended between the inner peripheral surface of the inner end portion of the hub 6d and the inner peripheral surface of the sleeve 98, and this sleeve 9
8 prevents the hub 6d from coming off. Further, a gear-shaped uneven portion 99 is formed on the outer peripheral surface of the distal end portion of the sleeve 98 so that this portion functions as an encoder. A rotation speed detection sensor 101 supported on the outer ring 1c via a seal ring 100 is
The rotational speeds of the sleeve 98 and the hub 6d can be detected so as to be opposed to the uneven portion 99.

[0013]

In the case of the first example of the conventional structure shown in FIG. 18, the transmission of rotational force between the first and second elements 4, 5 constituting the hub 6 is performed by welding 17 portions. Must be done in That is, it is necessary to transmit a large torque for driving between the first element 4 supporting the wheels and the second element 5 connected to the drive shaft.
Since they are fitted with each other on their cylindrical surfaces, a large torque cannot be transmitted on the fitting surfaces. Therefore, it is necessary to transmit a large torque at the above-mentioned welded portion 17, and in order to sufficiently increase the strength of the welded portion 17, the welding 1
It is necessary to make 7 a full circumference weld. However, when the welding 17 is a full-surround overlay welding, the shape of the inner raceway 8 formed on the outer peripheral surface of the first element 4 is distorted due to heat during welding, and the hardness of the inner raceway 8 is reduced. Or drop,
The durability of the rolling bearing unit including the inner raceway 8 cannot be sufficiently ensured.

In the case of the second example of the conventional structure shown in FIG. 19, the separation between the hub 6a and the drive shaft member 29 is prevented by the connecting member 31 made of an elastic material. Function is considered uncertain. That is, when the vehicle makes a sharp turn, the hub 6a is connected to the drive shaft member 2 based on a large thrust load applied to the hub 6a from the wheels.
A large force is applied in the direction of pulling out from 9. Despite such a large force, the connecting member 31 allows the hub 6a
It is difficult to reliably prevent the separation between the shaft member and the drive shaft member 29, and it is considered that sufficient reliability cannot be secured.

A third example of the conventional structure shown in FIG.
The present invention relates to a so-called semi-floating structure which is a non-independent suspension type suspension. In the case of such a structure, since a tripod type constant velocity joint is not incorporated, and a thrust load is not repeatedly applied to the axle 92 during traveling, a friction between a spline engagement portion between the axle 92 and the hub 6b is obtained. There is no need to consider wear prevention.
The third example of such a conventional structure has a completely different basic structure from the present invention on the assumption that the drive wheels supported by the independent suspension are rotatably supported by the suspension.

Further, in the case of the fourth example of the conventional structure shown in FIG. 21, the axial displacement of the spline engagement portion between the spline shaft 30 and the hub 6c is prevented regardless of the thrust load generated during operation. There is no mechanism provided. Because of this,
The elastic ring 96 is deformed based on a thrust load generated at the tripod-type constant velocity joint portion during operation and repeatedly and alternately applied to the spline shaft 30 from the housing portion 11 in the opposite direction, and the spline engagement portion slides. do. As a result, wear of the spline engagement portion advances,
It is not preferable because durability is impaired.

Further, in the case of the fifth example of the conventional structure shown in FIG. 22, there is an axial gap between the retaining ring and the mounting portion. Since no mechanism is provided for preventing axial displacement of the spline engaging portion based on the gap, wear of the spline engaging portion cannot be prevented. Further, in the case of the fifth example, since the spline engagement portion is provided at a portion protruding more inward than the inner end opening of the outer ring 1c,
The axial dimension of the entire wheel drive axle unit is increased, and a compact and lightweight structure cannot be realized. The wheel drive axle unit of the present invention has been invented in order to solve the above-mentioned inconveniences, prevent wear of the spline engagement portion, and achieve sufficient durability.

[0018]

The wheel drive axle unit of the present invention has an outer raceway on the inner peripheral surface, similarly to the wheel drive axle unit of the second example of the conventional structure shown in FIG. Then, the outer ring that does not rotate even during use, the mounting flange for supporting the wheel at the part near the one end of the outer peripheral surface, the inner ring raceway directly or through the inner ring at the part near the other end, the spline hole at the center, A hub provided at each end and a spline shaft that engages with the spline hole are provided at one end,
A drive shaft member having the other end as a housing part serving as an outer ring of a constant velocity joint, and a plurality of rolling elements rotatably provided between the outer ring track and the inner ring track. And
It is used in a state where rotational force is transmitted to the housing part via a tripod-type constant velocity joint.

In particular, in the wheel drive axle unit of the present invention, an inner engaging portion formed on the outer peripheral surface of the spline shaft over the entire circumference, and the above-mentioned inner engaging portion is aligned with the inner engaging portion. An outer engaging portion formed over the entire inner peripheral surface of the hub, a retaining ring, and a hub provided between the hub and the drive shaft member in a thrust direction between the hub and the drive shaft member. An elastic member for providing elasticity. Then, by positioning the retaining ring in the axial direction between the hub and the drive shaft member by bridging the retaining ring between the inner engagement portion and the outer engagement portion, the hub and the drive shaft member are formed by the elastic member. During the traveling, a greater thrust load is applied than the thrust load generated at the tripod type constant velocity joint portion and applied between the hub and the drive shaft member during traveling.

[0020]

In the wheel drive axle unit of the present invention configured as described above, torque transmission between the drive shaft member and the hub is performed based on the engagement between the spline shaft and the spline hole. Therefore, in order to surely transmit the torque between the drive shaft member and the hub, it is not necessary to perform processing that causes thermal distortion or the like, such as overlay welding, and each part of the rolling bearing unit including the inner raceway is used. Durability can be ensured.
Particularly, in the case of the present invention, the separation between the drive shaft member and the hub can be prevented by the inner and outer engagement portions and the retaining ring. Since the retaining ring is made of a material having sufficient strength, such as metal, the separation can be reliably prevented, and the reliability of the wheel driving axle unit can be ensured. Also, the structure of the present invention is:
Unlike the connection by the nut or the connection by welding, there is a possibility that an axial sliding movement may occur in the spline engagement portion. In addition, a thrust load generated at a tripod type constant velocity joint portion during traveling and larger than the thrust load repeatedly applied between the hub and the drive shaft member is applied. Therefore, the hub and the drive shaft member are not frequently axially displaced relative to each other based on the thrust load which changes in the direction and is generated in the tripod type constant velocity joint. Therefore, the occurrence of the sliding motion can be prevented, and the wear of the spline engagement portion can be prevented. As a result, the durability of the wheel drive axle unit including the spline engagement portion can be improved.

[0021]

1 to 3 show a first embodiment of the present invention. The outer ring 1 that does not rotate while being supported by the suspension device has a mounting portion 2 for supporting the suspension device on the outer peripheral surface, and double-row outer ring raceways 3 on the inner peripheral surface. Then, a hub 6a is provided on the inner diameter side of the outer ring 1,
It is arranged concentrically with the outer ring 1. In addition, inner ring raceways 8, 8 are provided directly or via separate inner races 50 at portions of the outer peripheral surface of the hub 6a facing the outer raceways 3, 3, respectively. The inner ring 50 is formed at a stepped portion 33 formed at an inner end of the main body portion of the hub 6a (an end closer to the center in the width direction of the vehicle when assembled to the vehicle, the right end in FIG. 1).
To the inner ring 50 at the inner end of the body portion.
The portion protruding from the inner end surface of the rim is fixed to the main body portion by a caulking portion 27 formed by caulking and expanding outward in the diameter direction.

A plurality of rolling elements 1 are provided between each of the outer raceways 3, 3 and each of the inner raceways 8, 8, respectively.
The hub 6a is rotatably supported inside the outer race 1 by providing the rollers 2 and 12 so as to be able to roll. Seal rings 19 and 19 are provided between the inner peripheral surfaces of both ends of the outer race 1, the outer peripheral surface of the intermediate portion of the main body of the hub 6 a, and the outer peripheral surface of the inner end of the inner race 50, respectively. The portion where the rolling elements 12, 12 are installed is isolated from the external space. Also, a cap 34 is provided at the outer end opening of the hub 6a.
Is fitted and fixed to close the outer end opening, thereby preventing foreign matter such as rainwater from entering the spline engaging portion described later from the outer end side. In addition, the outer end of the hub 6a (the end which is shifted outward in the width direction of the vehicle when assembled to the vehicle,
A mounting flange 7 for supporting and fixing the wheel to the hub 6a is provided on the outer peripheral surface of the left end of FIG.
It is provided integrally with the hub 6a.

A spline hole 28 is provided in the center of the hub 6a. Further, the hub 6a and the drive shaft member 29 are combined to form a wheel driving rolling bearing unit. A spline shaft 30 that engages with the spline hole 28 is provided at an outer end, which is one end of the drive shaft member 29. Further, an inner end, which is the other end of the drive shaft member 29, is a housing portion 11 serving as an outer ring of a Zeppa type constant velocity joint. A locking groove 39 for locking the outer end of a dustproof boot (not shown) is formed on the outer peripheral surface of the inner end of the housing portion 11.

In particular, in the wheel drive axle unit of the present invention, the entire outer peripheral surface of the spline shaft 30 near the outer end corresponds to the inner engaging portion described in the claims. An inner locking groove 14 is formed. In the inner peripheral surface of the intermediate portion near the outer end of the spline hole 28, the inner locking groove 1 is formed.
A step 43 or an outside locking groove (not shown), which corresponds to the outside engaging portion described in the claims, is formed over the entire circumference at a position corresponding to 4. And these inner locking grooves 14
2 and the stepped portion 43 (or an outside engaging groove not shown; the same applies hereinafter).
Are mounted so as to bridge between the inner locking groove 14 and the stepped portion 43.

The retaining ring 35 is made of spring steel or stainless steel.
Forming an elastic metal wire such as rod steel into a substantially C-shaped broken ring
By doing so, the diameter can be elastically expanded and contracted. This
Outer diameter D of the retaining ring 35 in a free state as shown in FIG.₃₅Is the sp
The maximum inscribed circle of the line hole 28 (the tip of the spline hole 28
Circle) diameter R₂₈That is all. Also, the inner locking groove 1
4 groove bottom diameter R₁₄, And above the step 43
Inner diameter of cylindrical surface portion 37 on the opposite side to spline hole 28
R₃₇Is that the retaining ring 35 is connected to the inner locking groove 14 and the step 4
It is regulated so as to be bridged between 3 and. That is,
The diameter R of the groove bottom of the inner locking groove 14₁₄Is the above spline hole
The diameter R of the largest inscribed circle of 28₂₈The retaining ring 35
Diameter d of the formed wire₃₅Less than twice the value of (R₁₄≤R
₂₈-2d₃₅). Such regulation is based on the above-mentioned retaining ring.
35 is pushed into the bottom of the inner locking groove 14
Then, the spline shaft 30 and the snap ring 35 together with the spline
This is necessary so that it can be freely inserted into the pipeline hole 28.
Also, the inner diameter R of the cylindrical surface portion 37 ₃₇Is the above spline shaft
The diameter of the largest circumscribed circle of 30 (the tip circle of the spline shaft 30)
D₃₀The diameter d of the wire constituting the retaining ring 35₃₅2
Less than doubled value (R₃₇<D₃₀+ 2d₃₅).
Such a restriction is that the diameter of the retaining ring 35 is elastically widened.
The inner peripheral edge of the retaining ring 35 and the inner locking
Necessary for engaging groove 14. Therefore, preferred
That is, the outer peripheral edge of the retaining ring 35 and the cylindrical surface portion 37
When the retaining ring 35 is in contact with the peripheral surface,
Diameter direction of the engaging portion between the in-hole 28 and the spline shaft 30
The inner diameter R of the cylindrical surface portion 37 is located at the center position.₃₇To
regulate.

In order to regulate the dimensions of the inner locking groove 14, the cylindrical surface portion 37, and the retaining ring 35 as described above, the spline shaft 30 is mounted with the retaining ring 35 mounted in the inner locking groove 14. Is inserted into the spline hole 28, the hub 6a and the drive shaft member 29 can be connected inseparably. That is, when connecting the hub 6a and the drive shaft member 29, the spline shaft 30 is connected to the spline hole 2 with the retaining ring 35 mounted in the inner locking groove 14.
8, from inside to outside, right to left in FIG. By this insertion work, the retaining ring 35 is moved to the caulking portion 27.
While being guided by a conical concave guide surface 36 provided adjacent to the inner peripheral surface of the spline hole 28 and the inner end of the spline hole 28.
The outer diameter is elastically reduced and pushed into the spline hole 28. When the inner locking groove 14 and the step 43 are aligned with each other, the diameter of the retaining ring 35 is adjusted so that the outer peripheral edge of the retaining ring 35 and the inner peripheral surface of the cylindrical surface portion 37 come into contact with each other. Until it spreads elastically. In a state where the diameter of the retaining ring 35 is elastically widened, the retaining ring 35 is bridged between the inner locking groove 14 and the step portion 43, and the spline shaft 30 is prevented from falling out of the spline hole 28, and the hub 6a and the drive shaft member 29 are inseparably coupled. The hub 6
The inclination angle of the guide surface 36 with respect to the axial direction of a is preferably 30 degrees or less so that the retaining ring 35 can pass through the guide surface 36 smoothly. Preferably, the spline shaft 30 and the spline hole 2
The thickening agent is a urea compound, the base oil is a synthetic oil and the base oil is a synthetic oil. Lubricate the engaging portion with the spline hole 28.

The width W of the inner locking groove 14 must be equal to or larger than the diameter d _{35 of the} wire constituting the retaining ring 35. The difference between the width W and the diameter d ₃₅ is as small as possible. I do. The reason for this is to prevent rattling of the joint between the inner locking groove 14 and the retaining ring 35.

In the case of this embodiment, a metal core 69 having the encoder 44 is externally fitted and fixed to an intermediate portion of the drive shaft member 29, that is, to an outer end of the housing portion 11. The rotation speed of the member 29 can be detected. This core metal 69
Is made by subjecting a plate material made of spring steel (including tool steel such as SK5) to press working and bending, and quenching and hardening the whole, and has a cross section having a cylindrical portion 45 and a circular ring portion 46. It is substantially L-shaped and formed entirely in an annular shape. Such a cored bar 69 includes the cylindrical portion 45 and the housing portion 1.
1 is fixed to the drive shaft member 29 by being externally fitted to the outer end portion by interference fit. The cylindrical portion 45 has a large number of slit-shaped through holes 47 which are long in the axial direction (the left-right direction in FIG. 1) and are equally spaced in the circumferential direction. Accordingly, the magnetic characteristics of the outer peripheral surface of the cylindrical portion 45 change alternately at regular intervals in the circumferential direction. That is, in the case of this example, the outer peripheral surface of the cylindrical portion 45 is the encoder portion 44. In the assembled state to the vehicle, the encoder section 44, which is the outer peripheral surface of the cylindrical section 45, has a detection section of a sensor 48 supported on a fixed portion such as a suspension device closely approached, and rotates in synchronization with wheels. The rotation speed of the drive shaft member 29 can be detected. In addition, the above-mentioned ring portion 46
Is in contact with the outer end surface of the housing portion 11.

In the case of the present embodiment, an inclined portion 66 which is inclined outward in the axial direction toward the inner diameter side is formed in the inner diameter side portion of the circular ring portion 46 constituting the cored bar 69, so that this circle is formed. A portion on the inner diameter side of the ring portion 46 is projected outward in the axial direction. Further, as shown in FIG. 3, a plurality of notches 67, 67 are formed at an inner peripheral edge of a portion on the inner diameter side of the circular ring portion 46 at equal intervals in the circumferential direction, so that each of the notches 67, 67 is formed. A plurality of tongue pieces 90, 90 are formed between the portions 67, 67, so that a portion on the inner diameter side of the annular portion 46 including the inclined portion 66 has sufficient elasticity. The spline shaft is formed by elastically abutting the tip of the tongue piece 90, 90 on the inner diameter side of the annular portion 46, that is, the tip of the tongue pieces 90, 90, against the end face of the caulking portion 27. 30
Prevents the spline hole 28 from being displaced leftward from the state shown in FIG. In the case of this example, the core metal 69 corresponds to the elastic member described in the claims, and the hub 6 a and the housing portion 11 of the drive shaft member 29 are
It gives elasticity in the direction away from each other. This allows
The rattling of the spline shaft 30 and the spline hole 28 in the axial direction is prevented. In this state, each of the tongue pieces 90, 90 is provided with an axial sliding resistance (several hundreds N = N) of a tripod type constant velocity joint (not shown) incorporated into a transmission (not shown) (right side in FIG. 1). Several tens kgf)
The above preload is applied. Accordingly, even when a load in the thrust direction (left-right direction in FIG. 1) is repeatedly applied to the Zeppa-type constant velocity joint including the housing portion 11 during operation based on the sliding resistance, the spline shaft 30 can be used. The engagement between the engagement portion and the spline hole 28 is prevented from sliding in the axial direction, thereby preventing the engagement portion from being worn.

If an excessive load is applied to the tongue pieces 90 during assembly, for example, the tongue pieces 9
Even when the first and second tongues 9 and 90 are bent between the hub 6a and the drive shaft member 29 and become flat, the tongues 9
The tongue pieces 90, 90 are designed so that the stress generated inside 0, 90 does not exceed the allowable stress, so that the tongue pieces 90, 90 are not damaged. That is, the stress generated inside the tongue pieces 90, 90 increases as the amount of displacement until the tongue pieces 90, 90 are flexed flat increases, so that the stress is flexed until the tongue pieces 90 become flat. The dimensions of the respective parts are determined so that the displacement amount at the time of being performed is suppressed to a value of 2 to 3 mm or less. A seal lip 6 formed entirely of an elastic material such as an elastomer such as rubber into a cylindrical shape is provided on an outer surface of the ring portion 46.
The inner end portion of the base member 8 is bonded and fixed by bonding or baking. At the same time, the outer edge, which is the leading edge of the seal lip 68, is brought into elastic contact with the inner end surface of the inner race 50 over the entire circumference, so that the outer end surface of the housing portion 11 and the end surface of the caulking portion 27 are brought into contact. Between the seals.

In the case of the wheel drive axle unit of the present invention constructed and assembled as described above, the drive shaft member 29 is provided.
The torque transmission between the spline shaft 3 and the hub 6a
This is performed based on the spline engagement between 0 and the spline hole 28. Therefore, in order to surely transmit the torque between the drive shaft member 29 and the hub 6a, it is necessary to form the entire circumference by welding or the like.
There is no need to perform processing that causes thermal distortion or the like. Therefore, the durability of each part of the rolling bearing unit including the inner raceway 8 formed on the outer peripheral surface of the intermediate portion of the main body of the hub 6a can be ensured. The separation between the drive shaft member 29 and the hub 6a can be prevented by the engagement between the inner locking groove 14, the step portion 43, and the retaining ring 35. This retaining ring 35 formed in a partially annular shape
Is made of a metal material having sufficient strength, such as spring steel or stainless spring steel, so that the separation can be reliably prevented, and the reliability of the wheel drive axle unit can be ensured.

The hub 6a is connected to the hub 6a by tongue pieces 90 provided on the inner peripheral edge of the core bar 69 based on the axial resistance of the tripod type constant velocity joint.
The step 43 is pressed against the retaining ring 35 by pressing with a thrust load larger than the thrust load applied to the ring. Therefore, regardless of the thrust load based on the axial resistance, the spline shaft 30 and the spline hole 28
Are prevented from rubbing against each other, so that the outer peripheral surface of the spline shaft 30 and the inner peripheral surface of the spline hole 28 can be prevented from being worn.
Further, a seal lip 68 is provided between the drive shaft member 29 and the hub 6a, and a spline engagement portion between the spline shaft 30 and the spline hole 28 is cut off from the external space together with the cap 34. Since the engaging portion is coated with grease as a lubricant, it is possible to more reliably prevent the spline engaging portion from being significantly worn by fretting or the like.

FIG. 4 shows a second embodiment of the present invention.
An example is shown. In the case of the present example, the cylindrical portion 45 forming the core bar 69a externally fitted and fixed to the outer end portion of the housing portion 11 includes:
No through hole 47 (FIG. 1) is formed. Further, in the case of the present example, notches 67, 67 (FIGS. 1 and 3) are not formed on the inner peripheral edge of a portion on the inner diameter side of the annular portion 46 constituting the cored bar 69a. Also, the inner diameter side portion is a diaphragm-shaped disc spring portion 91. In the case of this example, a cover 70 formed in a cylindrical shape by a part of the elastic material constituting the seal lip 68 is provided on an outer diameter side portion of the seal lip 68 connected to the outer surface of the ring portion 46. Provided. The leading edge of the cover 70 extends over the entire circumference to the outer diameter side of the small diameter step 71 formed at the inner end of the inner ring 50, thereby covering the seal portion formed by the seal lip 68. . For this reason, in the case of this example, the seal lip 6
The sealing function of the seal lip 68 is enhanced by preventing the foreign matter such as rain water from directly splashing on the seal 8.

In the case of this embodiment, a part of the elastic material constituting the seal lip 68 is attached to the outer surface of the disc spring portion 91 formed on the inner diameter side of the annular portion 46. The outer surface of the disc spring portion 91 is prevented from directly contacting the end surface of the caulking portion 27. The reason for this is to prevent fretting wear from occurring at the contact portion between the outer surface of the disc spring portion 91 and the end surface of the caulking portion 27.
In this case, in the case of this example, the cylindrical portion 45 constituting the cored bar 69a is used.
An outward flange-shaped flange portion 72 is formed on the inner end edge of the flange. When the core bar 69a is press-fitted into the outer end of the housing portion 11, the tip of the press-fitting jig abuts against the outer surface of the flange portion 72 without crushing the seal lip 68. I have. Other configurations and operations are the same as those of the above-described first example.

FIG. 5 shows a third embodiment of the present invention.
An example is shown. In the case of the present example, a step 73 is formed on the inner peripheral edge of the annular portion 46 that constitutes the metal core 69 b supported on the outer end of the housing portion 11, so that a portion on the inner diameter side of the annular portion 46 is formed. A part of the outer side surface, which connects the seal lip 68 and the base edge of the cover part 70, is close to the inner end face of the inner race 50. The amount of the elastic material forming the seal lip 68 and the covering portion 70 is reduced by the amount of the part of the outer surface of the annular portion 46 approaching the inner end surface of the inner ring 50 in this manner. 68 and cover 70
Is being reduced. Other configurations and operations are the same as those of the above-described second example.

FIG. 6 shows a fourth embodiment of the present invention.
An example is shown. In the case of this example, the cylindrical portion 45 of the metal core 69c that supports the seal lip 68a is externally fitted and fixed to a small-diameter step portion 71 formed at the inner end of the inner ring 50. At the same time, the inner surface of the disc spring portion 91 constituting the core bar 69c is elastically abutted against the outer end surface of the housing portion 11 via a part of the elastic material constituting the seal lip 68a. In addition, the distal end edge of the seal lip 68a is in contact with the outer peripheral surface of the housing portion 11 near the outer end of the conical inclined surface portion over the entire circumference. In this embodiment, the diameter of the distal end of the seal lip 68a in the free state is slightly larger than the diameter of the outer end surface of the housing portion 11. The reason is that when the spline shaft 30 is inserted into the spline hole 28, the seal lip 68
This is to prevent the front end edge of the seal lip a from hitting the outer end surface of the housing portion 11 and turning up the seal lip 68a.

The small-diameter stepped portion 71 formed on the inner end of the inner ring 50, which is a portion for fixing the cylindrical portion 45 of the cored bar 69c to the outside, is attached to the hub 6a by the inner end surface of the inner ring 50.
When caulking the inner end of the, it may be slightly deformed. For this reason, in the case of this example, even if the small diameter step 71 is deformed and the diameter or the like of the small diameter step 71 is changed, the fitting strength of the cylindrical portion 45 to the small diameter step 71 is changed. An elastic member 74 such as rubber is attached to the inner peripheral surface of the cylindrical portion 45 over the entire circumference in order to ensure the appropriateness of the fitting and to ensure the sealing performance of the fitting portion. Other configurations and operations are the same as those of the above-described third example.

FIG. 7 shows a fifth embodiment of the present invention.
An example is shown. In the case of this example, the base edge of the seal lip 68b is attached to the inner peripheral edge portion of the disc spring portion 91 constituting the metal core 69c, and the distal end edge of the seal lip 68b is attached to the intermediate portion of the drive shaft member 29. The elastic portion is elastically brought into contact with a curved portion existing at a continuous portion between the outer peripheral surface of the spline shaft 30 and the outer end surface of the housing portion 11. In addition, the core metal 69c
The base end of the covering portion 70a is connected to the inner surface of the inclined portion 66 provided on the inner diameter side portion of the circular ring portion 46, and the distal end edge of the covering portion 70a is connected to the outer end portion To cover the seal portion formed by the seal lip 68b over the entire circumference. Furthermore, in the case of this example,
The thickness of the elastic material that is present between the seal lip 68b and the cover 70a and whose inner surface is brought into contact with the outer end surface of the housing 11 is increased. The elastic plate 75 is provided. In this case,
Providing such an elastic plate portion 75 enhances the function of preventing the spline shaft 30 from being displaced leftward from the state shown in FIG. Therefore, in the case of the present example, the core bar 69c and the elastic plate portion 75 correspond to an elastic member described in claims. Other configurations and operations are the same as those of the above-described fourth example.

Next, FIGS. 8 and 9 show a sixth example of the embodiment of the present invention. Also in the case of this example, the spline shaft 30
An inner engaging groove 14 corresponding to the inner engaging portion described in the claims is formed over the entire outer peripheral surface of the intermediate portion near the outer end. A step 108 corresponding to the outer engaging portion described in the claims is provided around the outer end opening of the spline hole 28 formed in the center of the hub 6a at a position matching the inner engaging groove 14. , Formed over the entire circumference. Then, an annular retaining ring 109, a part of which is shown in FIG. 9, is provided between the inner locking groove 14 and the step 108 between the inner locking groove 14 and the step 108. It is worn in a state where it can be bridged.

The retaining ring 109 is formed in an annular shape as a whole by an elastic metal plate such as SK5 or other spring metal or stainless spring steel, and has a thickness dimension extending in the axial direction (the left-right direction in FIG. 8). It can be contracted freely. That is, the retaining ring 109 is provided with an annular portion 110 on the outer peripheral portion over the entire circumference, and a number of elastic tongues 111, 111 are provided on the inner peripheral edge of the annular portion 110 in the diametrically inward direction. And is formed so as to protrude outward in the axial direction. The diameter of the inscribed circle of the leading edge (inner peripheral edge) of the large number of elastic tongues 111 constituting such a retaining ring 109 is such that the spline shaft 30 is in a free state of the retaining ring 109. Is smaller than the diameter of the circumscribed circle. Such a retaining ring 109 elastically deforms the distal ends (inner peripheral ends) of the large number of elastic tongues 111 to the diametrically outward side of the retaining ring 109, and at the same time, the outer end of the spline shaft 30. Externally. Then, in a state where the plurality of elastic tongues 111, 111 are aligned with the inner locking grooves 14, the distal ends of the elastic tongues 111, 111 are elastically restored inward in the diametrical direction, and these elastic tongues 111, 111 are elastically restored. The tip of the elastic tongues 111, 111 and the inner locking groove 14
And are engaged. In this state, the annular portion 110 is
It abuts on the step 108.

Of course, each of the elastic tongues 111, 111
Through the spline grooves formed on the outer peripheral surface of the spline shaft 30, the groove bottom diameter of the inner locking groove 14 (the groove bottom diameter of the inner locking groove
The width of the tip of each of the elastic tongues 111 and 111 (the width is made larger than the width of the spline groove) and the like are regulated. In order to facilitate the operation of engaging the elastic tongues 111 and 111 with the inner locking groove 14, the annular portion 110 may be formed in a partially annular shape. At the tip of the spline shaft 30, the inner locking groove 1 is engaged with the retaining ring 109.
No spline groove is formed in the part closer to the tip than 4
It is also possible to make the cylindrical surface smaller in diameter than the diameter of the groove bottom of the spline groove. In this case, of course, the diameter of the bottom of the inner locking groove 14 is smaller than the outer diameter of the cylindrical surface. In the case of this example, the retaining ring 109 is attached after the spline shaft 30 is inserted into the spline hole 28. As in the first example shown in FIG. 1 described above, the spline shaft 30 cannot be inserted into the spline hole 28 with the retaining ring 35 mounted on the spline shaft 30 in advance.

Further, between the outer end surface of the housing portion 11 provided at the inner end portion of the drive shaft member 29 provided with the spline shaft 30 and the inner end surface of the hub 6a, a metal core 69d and an elastic plate 49 are provided. Is disposed. The core metal 69d constituting the sealing member 112 is made of SPCC
A metal plate such as a carbon steel plate is formed in an annular shape with an L-shaped cross section, and the cylindrical portion 45 formed on the outer peripheral edge is fitted to the outer end of the housing portion 11 by interference fitting. Thus, the housing 11 is fixed to the outer end.
The elastic plate 49 is formed by forming an elastomer such as rubber or vinyl into an annular shape. The elastic plate 49 is attached to the outer surface of the annular portion 46 constituting the cored bar 69d over the entire circumference by baking, bonding, or the like. are doing.

The elastic plate 49 of such a sealing member 112
The retaining ring 109 is connected to the inner locking groove 14 and the step portion 10.
8 and elastically clamped between the outer end surface of the housing portion 11 and the caulking portion 27 present on the inner end surface of the hub 6a. As described above, the elastic force for clamping the elastic plate 49 based on the elasticity of the retaining ring 109 is set slightly larger than the thrust load applied to the spline shaft 30 during operation, for example, about 980 N (= 100 kgf). As described above, the wheel supporting axle unit of the present embodiment includes the retaining ring 109 and the inner locking groove 14 and the step portion 10.
8, the elastic plate 49 is elastically sandwiched between the outer end surface of the housing portion 11 and the caulking portion 27 while being compressed in the axial direction. The positioning with respect to the member 29 in the axial direction is achieved. In the case of this example, the retaining ring 109 corresponds to the elastic member described in the claims, and the retaining ring also serves as the elastic member. In the case of this example, the first to fourth embodiments described above.
Unlike the five examples, a thrust load is applied in a direction in which the hub 6a and the housing 11 of the drive shaft member 29 approach each other.

In the case of the wheel drive axle unit of the present embodiment having the above-described configuration, the retaining ring 109 has elasticity in the axial direction, and the retaining ring 109 is formed in a stepped relation with the inner locking groove 14. The elastic plate 49 is elastically sandwiched between the caulking portion 27 existing on the other end surface of the hub 6 a and the outer end surface of the housing portion 11 in a state where the elastic plate 49 is bridged between the housing 108 and the housing 108. Therefore, irrespective of the vibration generated during operation, there is no generation of abnormal noise due to collision between members in each part. or,
During operation of the automobile, a thrust load generated at a tripod type constant velocity joint (not shown) provided on the differential gear side is applied to the drive shaft member 29 via a drive shaft (not shown). Since the direction of the thrust load changes in the operation state of the tripod type constant velocity joint, at a certain moment, a force is applied in a direction of pulling out the drive shaft member 29 from the hub 6a. Also in this case, the elastic plate 4
9 is set to, for example, about 980 N (= 100 kgf), which is sufficiently larger than the thrust load applied to the spline shaft 30 during operation of the tripod-type constant velocity joint. Shaft member 2
9 and the hub 6a are not displaced in the axial direction. Therefore, irrespective of the thrust load generated at the tripod-type constant velocity joint, the spline engagement portion between the drive shaft member 29 and the hub 6a does not rub, and wear of the spline engagement portion can be prevented. . Further, the caulking portion 27 and the elastic plate 49 are not separated from each other, and the sealing property between the drive shaft member 29 and the hub 6a by the elastic plate 49 is affected by the thrust load applied during the operation. Can be secured.

Next, FIGS. 10 to 11 show a seventh example of the embodiment of the present invention. In the case of the present example, a stop ring 109a that bridges between the inner locking groove 14 on the outer peripheral surface of the spline shaft 30 constituting the drive shaft member 29 and the step portion 108 on the inner peripheral surface of the hub 6a is not provided. An annular corrugated spring is used. The retaining ring 109a formed of the same elastic metal plate as the retaining ring 109 used in the sixth example described above.
Extends between the inner locking groove 14 and the step 108 while elastically expanding the inner diameter. Other configurations and operations are the same as those of the above-described sixth example, and therefore, the same reference numerals are given to the same parts, and the duplicate description will be omitted.

FIG. 12 shows an eighth embodiment of the present invention. In the case of the present example, a cylindrical portion 113 is formed at the tip of the spline shaft 30 constituting the drive shaft member 29. The outer diameter of the cylindrical portion 113 is smaller than the diameter of the inscribed circle at the bottom of the spline groove formed on the spline shaft 30. An inner engaging groove 14 corresponding to the inner engaging portion described in the claims is formed over the entire circumference at the axially intermediate portion of the cylindrical portion 113. A step 108 corresponding to the outer engaging portion described in the claims is provided around the outer end opening of the spline hole 28 provided at the center of the hub 6a at a position matching the inner engaging groove 14. , Formed over the entire circumference. The inner locking groove 14 and the step 1
08, the missing annular retaining ring 15 d and the annular spacer 114 are mounted in such a manner as to bridge the inner locking groove 14 and the step 108.

The retaining ring 15d is made of an elastic metal plate such as spring steel such as SK5, stainless steel spring steel, or the like, and is formed in a partially annular shape so that its diameter can be elastically expanded and contracted. The inner diameter of the retaining ring 15d in the free state is:
The outer diameter of the cylindrical portion 113 is smaller than the outer diameter. The inner diameter of the spacer 114 is slightly larger than the outer diameter of the cylindrical portion 113, and the outer diameter of the spacer 114 is sufficiently larger than the inner diameter of the spline hole 30.

Further, between the outer end surface of the housing portion 11 and the inner end surface of the hub 6a, the core bar 69d and the elastic plate 49 are connected similarly to the case of the sixth example shown in FIGS. Is disposed. Such a sealing member 1
The elastic plate 49 of the housing 12 is connected to the outer end surface of the housing 11 and the hub 6a in a state where the retaining ring 15d and the spacer 114 are bridged between the inner locking groove 14 and the step 108.
Is elastically compressed (with a preload applied) between the caulking portion 27 existing on the inner end surface of the member. Therefore, in the case of this example, unlike the first to seventh examples of the above-described embodiment, the elastic plate 49 constituting the seal member 112 corresponds to an elastic member described in claims. As described above, the wheel drive axle unit of the present example is configured such that the retaining ring 15d is extended between the inner locking groove 14 and the step portion 108 together with the spacer 114 while being compressed in the axial direction. The elastic plate 49 is elastically sandwiched between the outer end surface of the housing portion 11 and the caulking portion 27,
The positioning of the hub 6a and the drive shaft member 29 in the axial direction is achieved.

In the case of the wheel drive axle unit of the present embodiment, which is constructed as described above, the retaining ring 15d and the step 108
Since the spacer 114 is provided between the two, the contact between the retaining ring 15d and the step 108 with a small area can be prevented. As a result, during operation, the drive shaft member 29 and the hub 6
a, regardless of the thrust load applied between
It is possible to prevent fretting wear from occurring in 5d and the step 108. That is, since the retaining ring 15d is required to expand elastically when engaged with the inner locking groove 14, it is not made too wide, and the outer diameter of the retaining ring 15d is limited. Further, the diameter of the periphery of the opening of the spline hole 28 is somewhat large based on the chamfered portion existing in the opening. Therefore, when only the retaining ring 15d is provided between the inner locking groove 14 and the step 108, the step 108
The contact area between the contact ring and the retaining ring 15d is reduced, the surface pressure of the contact portion is increased, and fretting wear is easily generated in the contact portion. On the other hand, in the case of the wheel drive axle unit of this example, the spacer 114 is provided, and the contact area between both surfaces of the spacer 114 and the step portion 108 and the retaining ring 15d is ensured. It is possible to reduce the surface pressure of the contact portion and prevent the occurrence of fretting wear at the contact portion. The elastic plate 49
The elastic force (preload) applied to the spline shaft 30 during operation is the same as that in the sixth example shown in FIGS. 8 and 9 or the seventh example shown in FIGS. It is preferably set to be larger than the load, for example, about 100 kgf. Other configurations and operations are the same as those of the sixth and seventh aspects.
It is almost the same as in the example.

FIG. 13 shows a ninth embodiment of the present invention. In the case of this example, an elastic ring 115 made of an elastomer such as rubber or vinyl is provided between the spacer 114 and the step 108.
08 while being elastically compressed. In the illustrated example, the elastic ring 115 is
Is bonded to the inner surface by baking or bonding so that it can be handled integrally with the spacer 114. In the case of the present embodiment, foreign matter such as rainwater which enters the center hole of the hub 6a from the outer end opening of the center hole is removed by the elastic ring 115 between the spacer 114 and the step 108. In order to seal the gap, the cap 34 (FIG. 12) fitted to the hub 6a in the above-described eighth example is omitted. Other configurations and operations are the same as those of the above-described eighth example, and therefore, the same parts are denoted by the same reference numerals, and overlapping description will be omitted.

Next, FIG. 14 shows a tenth example of the embodiment of the present invention. In the case of this example, the outer diameter of the caulked portion 27 formed at the inner end of the hub 6a is related to the outer diameter of the inner ring 50 which is externally fitted and fixed to the inner end of the main body constituting the hub 6a. , Are smaller than those in the above-described eighth and ninth examples. Therefore, in the case of this example, the outer diameter half of the inner end face of the inner race 50 constituting the hub 6 a is exposed around the outer peripheral edge of the caulked portion 27.
In the case of the present example, a seal member 112 is provided between the outer-diameter side half of the inner end surface of the hub 6 a and the outer end surface of the housing portion 11. In the case of this example having such a structure, since the end face of the seal member 112 abuts against the end face of the flat inner ring 50, uniform distortion occurs in the seal member 112. As a result, the sealing member 112
Can increase the thrust load that can be supported. Other configurations and operations are the same as those in the ninth example described above, and therefore, the same reference numerals are given to the same parts, and duplicate description will be omitted. Note that the structure in which the seal member 112 is provided between the outer diameter side half portion of the inner end surface of the inner race 50 constituting the hub 6a and the outer end surface of the housing portion 11 is implemented by the structure of the above-described eighth example shown in FIG. You can do it.

Next, FIGS. 15 and 16 show an eleventh embodiment of the present invention. In the case of this example, the outer end opening of the space where the spline engagement portion between the spline shaft 30 and the spline hole 28 exists is closed by a cap 34a formed by combining the first element 116 and the second element 117. I have. The first element 116 is formed into a bottomed cylindrical shape by drawing a metal plate or the like, and covers the cylindrical portion 118 that is a fitting and fixing portion and the outer end opening of the cylindrical portion 118. And a bottom plate portion 119. An outward flange-shaped flange portion 120 is formed on the outer peripheral surface of the intermediate portion of the cylindrical portion 118 by buckling and deforming the metal plate so as to be folded 180 degrees. On the other hand, the second element 117
Is formed of a synthetic resin into a cylindrical shape with a bottom, and a cylindrical portion 121 whose outer peripheral surface matches or almost freely matches the shape of the inner peripheral surface near the outer end of the hub 6a; Bottom plate portion 1 as a closing plate portion provided so as to close the inner end opening of
22. The cylindrical portion 121 includes a large-diameter cylindrical portion 123, a small-diameter cylindrical portion 124, and a large-diameter cylindrical portion 1.
23 is provided with a continuous portion 125 that connects the inner edge of the small-diameter portion 23 and the outer edge of the small-diameter cylindrical portion 124. Also, the bottom plate portion 122
The small-diameter cylindrical portion 124 is provided so as to close the inner end opening.

Then, the first and second elements 12 as described above
By combining 6, 127 with each other,
The cap 34a is included. That is, when combining the first and second elements 116 and 117 with each other, as shown in detail in FIG. 16, the inner half of the cylindrical portion 118 constituting the first element 116 is The engaging concave groove 126 formed over the entire circumference on the outer peripheral surface near the outer end of the large-diameter cylindrical portion 123 constituting 117 is engaged. With this,
A locking projection 127 formed over the entire outer peripheral surface of the outer end portion of the large-diameter cylindrical portion 123 is formed on the inner peripheral surface of the intermediate portion of the cylindrical portion 118 with the formation of the flange portion 120. V
The groove 128 is engaged. In this state, the inner half of the cylindrical portion 118 and the locking groove 126 are combined.
, The engagement convex portion 127 and the V-shaped groove 1
The shape and dimensions of each part are regulated so that the engagement part with the seal 28 is sufficiently sealed.

In order to seal the opening at the outer end of the hub 6a,
When the cap 34a as described above is attached to the outer end opening of the hub 6a, the second element 117 is attached to the hub 6a.
a, and inserts the inner half of the cylindrical portion 118 of the first element 116 into the hub 6.
a at the outer end of the positioning cylindrical portion 129 provided at the outer end of
The inner fit is fixed by interference fit. At the same time, the collar 1
20 abuts against the outer end surface of the positioning cylindrical portion 129. The positioning cylindrical portion 129 is for positioning the driving wheel (not shown) with respect to the outer end of the hub 6a when the driving wheel (not shown) is mounted on the mounting flange 7. 7, the positioning cylindrical portion 129 is inserted into a circular hole formed at the center of (the wheel of) the driving wheel.

With the cap 34a attached to the outer end opening of the hub 6a in this manner, the outer peripheral surface of the cylindrical portion 121 constituting the second element 117 has an inner peripheral portion closer to the outer end of the hub 6a. The surface is almost in contact with or close to the entire surface. That is, the outer peripheral surface of the large-diameter cylindrical portion 123 is formed on the inner peripheral surface of the positioning cylindrical portion 129, and the small-diameter cylindrical portion 1 is formed on the inner peripheral surface of the small-diameter portion 130 formed on the inner peripheral surface of the hub 6a.
The outer surface of the continuous portion 125 substantially corresponds to the inclined portion 131 and the step portion 132 which are located between the inner peripheral surface of the positioning cylindrical portion 129 and the inner peripheral surface of the small diameter portion 130. Touch At the same time, the second element 117
Of the spline shaft 30 and the front end surface of the spline shaft 30 in a state where the bottom plate 122 obstructs the outer end opening of the space where the spline engagement portion between the spline shaft 30 and the spline hole 28 exists.

As described above, in the case of this example, the cap 34
By providing the bottom plate portion 122, which is a closing plate portion, which constitutes a in the axial direction more inward than the cylindrical portion 118, which is the fitting and fixing portion, the bottom plate portion 122 is brought into close proximity to the distal end surface of the spline shaft 30. I have. Therefore, the volume of the space in which the spline engagement portion between the spline shaft 30 and the spline hole 28 exists is reduced, and the amount of grease sealed in this space can be reduced. In the case of this example, the grease sealed in this space is a portion on the axially outer end side from the bottom plate portion 122, that is, the outer peripheral surface of the cylindrical portion 121 constituting the second element 117 and the hub 6a. There is a possibility of entering the portion between the outer peripheral portion and the inner peripheral surface. However, the connecting portion between the first and second elements 126 and 127 and the fitting portion between the cylindrical portion 118 and the positioning cylindrical portion 129, which are present at the axially outer ends of the portion between these two peripheral surfaces, It has sufficient sealing properties. Therefore, even if grease enters the portion between the two peripheral surfaces, the grease does not leak to the outside through the engaging portion and the fitting portion. Further, in the case of this example, the cylindrical portion 118 as the fitting / fixing portion is internally fitted and fixed to the outer end of the positioning cylindrical portion 129 which is the outer end opening of the hub 6a. Therefore, the work of internally fitting and fixing the cylindrical portion 118 to the hub 6a can be easily performed. The structure of the seal member including the core bar 69a incorporated in this example is the same as that of the second example shown in FIG.

Next, FIG. 17 shows a twelfth example of the embodiment of the present invention. In the case of this example, the first element 116a constituting the cap 34b is manufactured by die-casting an aluminum alloy. Further, by this die casting, a molding 133 for improving the design is formed on the outer surface of the bottom plate portion 119 constituting the first element 116a.
Has been given. On the other hand, the synthetic resin second element 117a constituting the cap 34b is integrally connected to the first element 116a by blow molding. Therefore, the outer edge of the large-diameter cylindrical portion 123 constituting the second element 117a is adhered over the entire periphery to the inner edge of the cylindrical portion 118 constituting the first element 116a. In addition, this cylindrical part 1
By forming a through hole or a concave hole at the tip end of 18, the coupling strength between the first and second elements 116a and 117a can be improved. Further, in order to perform the blow molding as described above, the bottom plate 1 constituting the first element 116a is formed.
At a central portion of 19, a blowing port 134 for blowing air into a portion between the first element 116a and the second element 117a is formed. The blowing port 134 is closed after the completion of the cap 34b. In the case of the present example, a small-diameter cylindrical member is provided on the cylindrical portion 121 so as to match the shape of the outer peripheral surface of the cylindrical portion 121 constituting the second element 117a with the shape of the inner peripheral surface near the outer end of the hub 6a. The part 124 (see FIG. 15) is not formed. Other configurations and operations are the same as those of the above-described eleventh example.

[0058]

Since the present invention is constructed and operates as described above, the present invention realizes a wheel drive axle unit which is small and lightweight, and has excellent durability and reliability. It can contribute to improvement of power performance and fuel efficiency. Also, it is possible to prevent the components from colliding with each other during driving, to prevent abnormal noise, vibration, and fretting wear, to improve the comfort of the vehicle incorporating the wheel drive axle unit, and to improve the wheel drive. The durability of the vehicle axle unit itself can be further improved.

[Brief description of the drawings]

FIG. 1 is a half sectional view showing a first example of an embodiment of the present invention.

FIG. 2 is a view of the retaining ring as viewed from the side in FIG. 1;

FIG. 3 is a view of a part of the core metal and the seal lip as viewed from the left side of FIG. 1;

FIG. 4 is a half sectional view showing a second example of the embodiment of the present invention.

FIG. 5 is a half sectional view showing the third example.

FIG. 6 is a half sectional view showing the fourth example.

FIG. 7 is a half sectional view showing the fifth example.

FIG. 8 is a half sectional view showing the sixth example.

FIG. 9 is a partially enlarged perspective view of a retaining ring used in a sixth example.

FIG. 10 is a half sectional view showing a seventh example of the embodiment of the present invention.

FIG. 11 is a partially enlarged perspective view of a retaining ring used in a seventh example.

FIG. 12 is a half sectional view showing an eighth example of the embodiment of the present invention.

FIG. 13 is a half sectional view showing the ninth example.

FIG. 14 is a half sectional view showing the tenth example.

FIG. 15 is a half sectional view showing the eleventh example.

FIG. 16 is an enlarged view of a portion A in FIG. 15;

FIG. 17 is a half sectional view showing a twelfth example of the embodiment of the present invention.

FIG. 18 is a partial sectional view showing a first example of a conventional structure.

FIG. 19 is a half sectional view showing the second example.

FIG. 20 is a sectional view showing the third example.

FIG. 21 is a sectional view showing the fourth example.

FIG. 22 is a sectional view showing the fifth example.

[Explanation of symbols]

 1, 1a, 1b, 1c Outer ring 2 Mounting part 3 Outer ring track 4 First element 5 Second element 6, 6a, 6b, 6c, 6d Hub 7 Mounting flange 8 Inner ring track 9 Cylindrical part 10 Constant velocity joint 11 Housing part 12 Roll Moving body 13 Outer locking groove 14 Inner locking groove 15, 15a, 15b, 15c, 15d Retaining ring 16 Step 17 Welding 18 Cover 19 Seal ring 20 Separator 21 Inner ring 22 Retaining part 23 Ball 24 Inner engaging groove 25 Outer Engaging groove 26 Pocket 27 Caulking portion 28 Spline hole 29 Drive shaft member 30 Spline shaft 31 Coupling member 32 Encoder 33 Step portion 34, 34a, 34b Cap 35 Retaining ring 36 Guide surface 37 Cylindrical surface portion 39 Locking groove 40 Knuckle 43 Step portion 44 Encoder part 45 Cylindrical part 46 Ring part 47 Through hole 48 Sensor 49 Elastic plate (bullet 50 Inner ring 66 Inclined portion 67 Notch 68, 68a, 68b Seal lip 69, 69a, 69b, 69c, 69d Core 70, 70a Cover 71 Small step 72 Flange 73 Step 74 74 Elastic material 75 Elastic plate Part 90 Tongue piece 91 Disc spring part 92 Axle 93 Axle tube 94 Engagement groove 95 Locking part 96 Elastic ring 97 Retaining ring 98 Sleeve 99 Uneven part 100 Seal ring 101 Rotational speed detection sensor 108 Step part 109, 109a Retaining ring 110 yen Ring part 111 Elastic tongue piece 112 Seal member 113 Column part 114 Spacer 115 Elastic ring 116, 116a First element 117, 117a Second element 118 Cylindrical part 119 Bottom plate part 120 Flange part 121 Cylindrical part 122 Bottom plate part 123 Large diameter cylinder Part 124 small-diameter cylindrical part 125 continuous part 126 locking concave groove 127 locking Part 128 V-shaped groove 129 positioned cylindrical portion 130 small-diameter portion 131 inclined portion 132 stepped portion 133 shaped 134 blowing port

 ──────────────────────────────────────────────────続 き Continued on the front page (31) Priority claim number Japanese Patent Application No. 10-252641 (32) Priority date September 7, 1998 (September 9, 1998) (33) Priority claim country Japan (JP) (31) Priority claim number Japanese Patent Application No. 10-253983 (32) Priority date September 8, 1998 (9.8.9.8) (33) Priority claim country Japan (JP) (72) Inventor Takeo Okuma 1-5-50 Kugenuma Shinmei, Fujisawa-shi, Kanagawa Nippon Seiko Co., Ltd.

Claims (3)

[Claims] 1. An outer raceway having an outer raceway on an inner peripheral surface, which does not rotate during use, a mounting flange for supporting a wheel at a portion near one end of the outer peripheral surface, and a direct or inner ring at a portion near the other end. The inner ring raceway, a hub provided with a spline hole at the center, and a spline shaft engaging with the spline hole are provided at one end, and the other end is a housing part serving as an outer ring of a constant velocity joint. A state in which a drive shaft member and a plurality of rolling elements rotatably provided between the outer raceway and the inner raceway are transmitted to the housing via a tripod-type constant velocity joint. In the wheel drive axle unit used in, the inner engaging portion formed over the entire outer peripheral surface of the spline shaft,
An outer engaging portion formed over the entire inner peripheral surface of the hub at a position aligned with the inner engaging portion; a retaining ring; and a hub provided between the hub and the drive shaft member. And an elastic member for imparting elasticity in the thrust direction between the hub and the drive shaft member. Along with positioning in the axial direction, a thrust load generated between the hub and the drive shaft member by the elastic member at the tripod type constant velocity joint portion during traveling and applied between the hub and the drive shaft member. An axle unit for driving wheels, wherein a larger thrust load is applied. 2. A spline engagement portion between a spline hole and a spline shaft is sealed by elastically sandwiching a seal member made of an elastic material between the hub and the drive shaft member in the axial direction.
The wheel drive axle unit according to claim 1. 3. The wheel drive axle unit according to claim 1, wherein the retaining ring also serves as an elastic member.