JPH11321211A - Axle hub of vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To protect the taper roller group of a unit bearing from penetration of water or dust to ensure the performance of the bearing by arranging an annular sealant between both butted end surfaces of a pair of inner races. SOLUTION: An O-ring consisting of an annular sealant 13 is fitted to a pair of annular grooves 12, 12. Accordingly, the annular sealant 13 is arranged between both butted end surfaces 7C, 7C of a pair of inner races. There is the fear that a clearance S2 is formed between the circumferential surface 4A of a bearing shaft part 4 and each inside surface 7A of the inner races 7, 7. In this case, water or dust possibly gets into the clearance S2 from the circumferential part of a unit bearing 6, and then penetrates into the unit bearing 6 from the both butted end surfaces 7C, 7C of the inner races 7, 7. According to this structure, the inter part of the unit bearing 6 is interrupted to the clearance 2 by the annular sealant 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an axle hub for a vehicle, and more particularly, to an axle hub equipped with a unit bearing.

[0002]

2. Description of the Related Art An axle hub is provided at an end of an axle to support a load of a vehicle such as a truck. For example, a unit bearing is used for the axle hub.

FIGS. 7 and 8 show an example of this type of axle hub. In the figure, reference numeral 101 denotes an axle, and the axle 101 is a dead axis of a rear axle of a vehicle (not shown). The axle 101 has an axle body 102. Axle body 1 is provided at end 101A of axle 101.
02, the small diameter portion 103, the bearing shaft portion 104
Are formed. The small diameter portion 103 is continuous with a bearing shaft portion 104 having a smaller diameter than the small diameter portion 103 via a step portion 105.

A unit bearing 106 is mounted on the bearing shaft 104. The unit bearing 106 includes a pair of inner races 107, 107, an outer race 108 disposed on the outer periphery of the pair of inner races 107, 107, and a pair of inner races 107, 10.
7 and the outer race 108, taper roller groups 109, 109 facing each other, and each taper roller group 1
And a pair of built-in seal members 110 and 110 disposed on both sides of the first and second 09 and 109, respectively.

[0005] The components of the unit bearing 106 will be described. A pair of inner races 107,
107 are arranged side by side along the axial direction, and are externally fitted to the bearing shaft 104. Outer race 108
An annular flange 111 is formed at a radially outer end of a portion 108B on the outer side in the vehicle left-right direction. The female screw portion 114 is cut at a plurality of locations on the annular flange 111. End surfaces 107C, 107C of the pair of inner races 107, 107 facing each other are in abutting state. A pair of internal sealing members 110, 110
Are for protecting the tapered roller groups 109, 109.

Next, a structure in which the unit bearing 106 is fixed on the bearing shaft 104 will be described. A ring member 11 is attached to the end 101A of the axle 101.
2 has been inserted. Ring member 112 is axle 1
The nut member 11 is attached to the screw portion 101B of the end portion 101A of FIG.
3 is fastened to the bearing shaft 104 by screwing. As a result, the side end face 107D of the inner race 107 on the outer side in the left-right direction of the vehicle is
From the vehicle in the left-right direction. Therefore, the unit bearing 106 is sandwiched between the step portion 105 of the axle 101 and the ring member 112.
Thus, the unit bearing 106 is fixed on the bearing shaft 104.

The hub flange 116 is connected to the annular flange 111 by tightening a bolt 115 to each of the female thread portions 114 of the annular flange 111.
The hub flange 116 has a hole 116 </ b> C for disposing the ring member 112 and the nut member 113, and is a disk having a larger diameter than the annular flange 111. The unit bearing 106 and the hub flange 116 form an axle hub H1.

A brake drum 118 is provided on an inner side surface 116A of the hub flange 116 with bolts 117A and nuts 117.
B attached. In addition, hub flange 11
The disk wheel 119 is attached to the outer surface 116B of the sixth unit 6 by bolts 117A and nuts 117B. Note that a cap 120 is placed over the end 101A of the axle 101, and the cap 120 is fixed by bolts 115. A gasket 121 is adhered to the outer surface 116B of the hub flange 116, and the gasket 121 is fixed on the outer surface 116B of the hub flange 116 by tightening a bolt 115. The cap 120 and the gasket 121 prevent water, mud, dust and the like from entering the inside of the hub flange 116.

The outer peripheral surface 104A of the bearing shaft 104 and the inner peripheral surface 107A of the inner race 107 are in metal contact. During normal use of the vehicle, there is no elastic distortion of the axle hub H1 in the assembled state, and therefore, intrusion of water, dust, and the like between the outer peripheral surface 104A of the bearing shaft 104 and the inner peripheral surface 107A of the inner race 107 does not occur. Has been prevented.

[0010]

However, in the conventional vehicle axle hub H1, when the load of the vehicle is large or when the vehicle is not used during normal use such as when making a sharp turn,
There is a possibility that the axle hub H1 in the assembled state may be elastically deformed. Due to this elastic strain, as shown in FIG. 8, a gap S1 is generated between the side end surface 107B of the inner race 107 on the inner side in the vehicle left-right direction and the wall surface 105B of the step portion 105 of the axle, and the outer peripheral surface of the bearing shaft portion 104. There may be a gap S2 between the inner peripheral surface 107A of the inner race 107 on the inner side in the vehicle left-right direction.

For this purpose, as shown by an arrow Y1, a gap S is provided from outside the unit bearing 106 through the gap S1.
Second, there is a risk that water, dust, etc. may enter. 8, a gap S3 is formed between the side end surface 108A of the outer race 108 and the inner side surface 116A of the hub flange 116 due to the elastic strain of the axle hub H1, and the side of the inner race 107 on the outer side in the vehicle left-right direction. A gap S4 may be formed between the end surface 107D and the ring member 112, and a gap S2 may be formed between the outer peripheral surface 104A of the bearing shaft 104 and the inner peripheral surface 107A of the inner race 107 on the outer side in the vehicle left-right direction. is there. Therefore, as shown by the arrow Y2, the gap S3 is provided from outside the unit bearing 106.
Water, dust, and the like may enter the gap S2 via S4.

As described above, when water, dust, or the like enters the gap S2, the water, dust, or the like, as shown by an arrow Y3, extends between the two end faces 107C, 107C of the pair of inner races 107, 107. There is a risk of infiltrating into the interior of the bearing 106. The water, dust, and the like may include metal powder generated by wear between the bearing shaft 104 and the unit bearing 106.

As a result, the durability of the unit bearing 106 is not ensured, and the performance of the unit bearing 106 may be deteriorated. SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a tapered roller for a unit bearing even if water, dust, or the like enters between a bearing shaft and an inner race of the unit bearing. An object of the present invention is to provide an axle hub for a vehicle that can protect a group and ensure bearing performance.

[0014]

According to the first aspect of the present invention,
A unit bearing mounted on a bearing shaft formed at the end of the axle via a step, and a hub flange coupled to the unit bearing;
The unit bearing includes a pair of inner races that are externally fitted to the bearing shaft portion and that are arranged side by side along the axial direction by abutting opposed end surfaces, and a pair of outer races that are arranged on the outer periphery of the inner race. In an axle hub of a vehicle including a pair of tapered rollers arranged opposite to each other between an inner race and an outer race, and a pair of built-in seal members arranged on both sides of the pair of tapered rollers, the pair of inner races is provided. An annular seal member is provided between both end surfaces of the abutting member.

According to a second aspect of the present invention, in the vehicle axle hub according to the first aspect, the annular sealing member is an O-ring. According to a third aspect of the present invention, in the axle hub of the vehicle according to the first aspect, an annular groove formed by cutting out an inner peripheral end portion is formed in an end face where the pair of inner races abut. I do.

(Function) In the first aspect of the present invention,
A gap is formed between the outer peripheral surface of the bearing shaft portion and the inner peripheral surface of the inner race, and water, dust, and the like may enter the gap. In this case, the inside of the unit bearing is shut off from the gap by the annular sealing material.

According to the second and third aspects of the invention, the same operation as the first aspect of the invention is produced.

[0018]

Embodiments of the present invention will be described below with reference to the drawings.

Referring to FIGS. 1 and 2, an axle hub of a vehicle according to an embodiment of the present invention will be described with an example of a dead axle of a rear axle as an axle. In the figure, reference numeral 1 denotes an axle,
Is a dead axis of a rear axle of a vehicle (not shown).

The axle 1 has an axle body 2. A small diameter portion 3 and a bearing shaft portion 4 are formed at an end 1A of the axle 1 so as to be continuous with the axle body 2. The small diameter portion 3 is continuous with the bearing shaft portion 4 having a smaller diameter than the small diameter portion 3 via the step portion 5. A unit bearing 6 is mounted on the bearing shaft 4. The unit bearing 6 includes a pair of inner races 7, 7 and an outer race 8 arranged on the outer periphery of the pair of inner races 7, 7.
And a pair of tapered roller groups 9, 9 disposed facing each other between the pair of inner races 7, 7 and the outer race 8.
And a pair of built-in seal members 10, 10 arranged on both sides of each tapered roller group 9, 9.

The components of the unit bearing 6 will be described. The pair of inner races 7, 7 are arranged side by side along the axial direction, and are externally fitted to the bearing shaft 4. Opposing end surfaces 7C, 7C of the pair of inner races 7, 7 are in an abutting state. Both end surfaces 7C, 7 of a pair of inner races 7, 7 butted against each other.
C, a pair of semicircular annular grooves 12, 1
2 are formed facing each other. An annular flange 11 is formed at a radially outer end of a portion 8B of the outer race 8 on the outer side in the vehicle left-right direction. The female thread portion 14 is cut at a plurality of locations on the annular flange 11 of the unit bearing 6. A pair of internal sealing members 10,
Reference numeral 10 is for protecting the pair of tapered roller groups 9 and 9.

Next, a structure in which the unit bearing 6 is fixed on the bearing shaft 4 will be described. A screw portion 1B is formed outside the bearing shaft portion 4 at the end portion 1A of the axle 1 in the vehicle left-right direction, and a ring member 1C is inserted through the screw portion 1B. The ring member 1C is
The nut 1 </ b> D is screwed into the screw 1 </ b> B to be tightened on the bearing shaft 4. This allows
A side end face 7E of the inner race 7 on the outer side in the vehicle left-right direction receives a pressing force from the ring member 1C toward the inside in the vehicle left-right direction. Therefore, the unit bearing 6 is sandwiched between the step portion 5 of the axle 1 and the ring member 1C. In this manner, the unit bearing 6 is mounted on the bearing shaft 4.
Fixed on top.

Each female thread portion 1 of the annular flange 11
The hub flange 16 is connected to the annular flange 11 by tightening the bolts 15 to the respective 4. The hub flange 16 includes a ring member 1C, a nut member 1
D having a hole 16E for the arrangement of the annular flange 11
It is a larger disk. The unit bearing 6 and the hub flange 16 constitute an axle hub H.

A brake drum 18 is attached to an inner side surface 16A of the hub flange 16 by bolts 17A and nuts 17B. Also, the outer surface 1 of the hub flange 16
A disk wheel 19 is attached to 6B by bolts 17A and nuts 17B. A cap 20 is placed over the end 1A of the axle 1, and the cap 20
Are fixed by bolts 15. Further, a gasket 21 is attached to the outer side surface 16B of the hub flange 16,
The gasket 21 is fixed on the outer surface 16B of the hub flange 16 by tightening a bolt 15. Cap 2
0, the gasket 21 prevents water, mud, dust and the like from entering the inside of the hub flange 16.

And, in the pair of annular grooves 12, 12,
An O-ring made of an annular sealing material 13 is fitted. In this manner, the annular seal member 13 is disposed between the two end faces 7C of the pair of inner races. Thus, in the present embodiment, there is a possibility that a gap S2 is formed between the outer peripheral surface 4A of the bearing shaft 4 and the inner peripheral surfaces 7A of the inner races 7, 7 (the same as in the case of the conventional vehicle load). Is large, or when it is not used during normal use such as when turning sharply). In this case, as shown by arrows Y1 and Y2, water, dust, etc.
There is a risk of entering the gap S2.

Then, in the same manner as in the prior art, the water, dust and the like are brought into contact with both end faces 7C, 7 of the pair of inner races 7, 7.
C tries to enter the inside of the unit bearing 6 from between C. Here, the inside of the unit bearing 6 is blocked by the annular seal material 13 with respect to the gap S2.

Therefore, even if water, dust or the like enters the gap S2 between the bearing shaft 4 and the inner races 7,7,
The annular sealing material 13 prevents water, dust and the like from entering the inside of the unit bearing 6, protects the tapered roller groups 9, 9 of the unit bearing 6, ensures durability, and ensures the bearing performance. It works. Especially,
As in the conventional case, when the water, dust, and the like include metal powder generated by abrasion between the bearing shaft 4 and the unit bearing 6, if the water, dust, or the like containing the metal powder, Intrusion into the unit bearing 6 can be prevented.

In the present embodiment, the axle hub of the vehicle has been described using the dead axle of the rear axle as an example, but the invention can also be applied to the drive axle of the rear axle. In this case, the unit bearing is mounted on an axle composed of a rear axle housing. It can also be applied to the front axle.

In this embodiment, a pair of annular grooves 1 are formed in both end faces 7C of the pair of inner races 7,7.
The inner races 2 and 12 are formed in an abutted state. However, an annular groove is formed only on one end face 7C of one inner race 7, and an annular sealing material can be fitted into this annular groove. Furthermore, in the present embodiment, a pair of annular grooves 1
The example in which the O-ring made of the annular sealing material 13 is fitted into the inner races 2 and 12 has been described. However, the present invention is not limited to this. For example, it is also possible to dispose an annular sealing material made of a flat ring.

In this embodiment, an example in which the annular seal member 13 is applied to an O-ring has been described. However, the configuration shown in FIG. 3 may be employed. In the figure, both end faces 7 of a pair of inner races 7,
C, 7C are formed with cutout annular grooves 22, 22 continuous with the inner peripheral ends 7D, 7D. Annular groove 2
The reference numerals 2 and 22 are located closer to the axis L than the annular sealing member 13 formed of an O-ring. Undercut portions 23, 23 are formed in the annular grooves 22, 22, respectively.

A connecting piece 24 is locked in the annular grooves 22,22. The connecting piece 24 is an annular body having a substantially U-shaped cross section, and has flange portions 24A, 24A. The connection piece 24 strengthens the connection between the inner races 7, 7, and thus improves the sealing performance of the annular seal member 13. Referring to FIG. 4, an axle hub of a vehicle according to the first and third embodiments of the invention will be described by taking a dead axle of a rear axle as an example of an axle.

The basic structure on which the axle hub of the vehicle according to the present embodiment is based is the same as that described for the axle hub of the vehicle according to the first and second embodiments of the present invention. The same parts are denoted by the same reference numerals and description thereof will be omitted, and only different parts will be described.

In the figure, the annular grooves 31, 31 in the axle hub H are formed by cutting out the inner peripheral ends 7D, 7D at both end faces 7C, 7C where the pair of inner races 7, 7 abut. A pair of annular grooves 31, 31
A ring-shaped sealing member 3 made of a rubber material and having a rectangular cross section.
2 is fitted. In this way, the annular seal member 32 is disposed between the two end faces 7C, 7C of the pair of inner races 7, 7.

The inner peripheral surface 32A of the annular sealing material 32
Contact the outer peripheral surface 4A of the bearing shaft portion 4 and receive a pressing force, and at the same time, the side surfaces 32B, 32B
Are in contact with the wall surfaces 31A, 31A of the annular grooves 31, 31 and receive the pressing force. As a result, the annular sealing material 32 is compressed into the annular grooves 31 and 31 and is pushed in close contact. Therefore, the sealing performance can be improved.

According to the above-described structure, similarly to the effect of the axle hub H of the vehicle according to the first and second aspects of the present invention, the distance between the bearing shaft 4 and the inner race 7 is increased. Even if water, dust, or the like intrudes into the gap S2, water or dust enters the unit bearing 6 due to the annular seal material 32.
This prevents the intrusion of dust and the like, protects the tapered roller groups 9, 9, ensures durability, and has the effect of ensuring the bearing performance.

In the present embodiment, the axle hub of the vehicle has been described by taking the dead axle of the rear axle as an example, but the invention can also be applied to the drive axle of the rear axle. In this case, the unit bearing is mounted on an axle composed of a rear axle housing. It can also be applied to the front axle. Further, in the present embodiment, the annular sealing material 32 is fitted into the pair of annular grooves 31 with the inner peripheral surface 32A thereof in contact with the outer peripheral surface 4A of the bearing shaft portion 4.
The configuration shown in FIG. 5 can also be used.

In the figure, annular grooves 33, 33 are provided at both end faces 7C, 7C of the pair of inner races 7, 7 at which they abut.
Are inner end portions 7D, 7D of the end surfaces 7C, 7C.
Is formed by cutting out continuously. Annular grooves 33, 3
3 has a recess 34, 34, respectively.
An annular sealing member 35 made of rubber material and having a rectangular cross section is arranged on the annular grooves 33, 33. A connection piece 36 is provided on the annular sealing material 35. Connecting piece 36
Is an annular body having a substantially U-shaped cross section, and has flange portions 36A, 36A.
A. The annular sealing material 35 includes a connecting piece 36.
And are in close contact with each other.
The engagement of the connecting piece 36 with the annular grooves 33, 33 securely fixes the annular seal material 35 in the annular grooves 33, 33, and strengthens the connection of the inner races 7, 7.
Therefore, the sealing performance of the annular sealing material 35 can be improved.

Then, as shown in FIG. 6, it is possible to assemble the connecting piece 36 as shown in FIG. 5 with the connecting piece 36 protruding from the inner peripheral surface 7A of the inner race 7 by the projection amount δ. In this case, the annular seal member 35 is fitted into the pair of annular grooves 33, 33 while receiving the pressing force from the bearing shaft 4. Thereby, the annular sealing member 35 is further compressed by the pressing force of the bearing shaft 4 into the connecting piece 36 and is in close contact with the connecting piece 36. Therefore, the sealing performance can be further improved.

[0039]

According to the first aspect of the present invention, even if water, dust or the like enters between the bearing shaft and the inner race of the unit bearing, the taper rollers of the unit bearing are protected and the bearing performance is improved. An effect that can be secured is exerted. According to the second and third aspects of the present invention, the same effects as the effects of the first aspect of the invention can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an axle hub according to an embodiment of the present invention.

FIG. 2 is a sectional view of a main part of the axle hub.

FIG. 3 is a sectional view of a main part showing a modification of the axle hub.

FIG. 4 is a sectional view of a main part of the axle hub according to the embodiment of the first and third aspects of the invention.

FIG. 5 is a sectional view of a main part showing a modification of the axle hub.

FIG. 6 is a sectional view of a main part showing a modification of the axle hub.

FIG. 7 is a sectional view showing a conventional axle hub.

FIG. 8 is a sectional view showing a unit bearing of the axle hub.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Axle 1A end part 4 Shaft part for bearing 6 Unit bearing 7 Inner race 8 Outer race 9 Tapered roller group 10 Sealing member for incorporation 13 Annular sealing material 16 Hub flange H Axle hub

Claims (3)

[Claims] 1. A unit bearing mounted on a bearing shaft formed at an end of an axle via a step portion, and a hub flange coupled to the unit bearing, wherein the unit bearing comprises: A pair of inner races which are externally fitted to the bearing shaft portion and are arranged side by side along the axial direction with the opposing end faces facing each other; an outer race arranged on the outer periphery of the inner race; a pair of inner races and an outer race. An axle hub of a vehicle comprising a pair of tapered rollers arranged to face each other and a pair of built-in sealing members arranged on both sides of the pair of tapered rollers; An axle hub for a vehicle, wherein an annular seal member is disposed between the axle hubs. 2. The axle hub according to claim 1, wherein said annular seal member is an O-ring. 3. The axle hub for a vehicle according to claim 1, wherein an annular groove formed by cutting out an inner peripheral end portion is formed in an end face where the pair of inner races abut.