KR102391537B1 - An axle assembly for a driving wheel of vehicle - Google Patents

Abstract

The present invention provides a driving wheel axle assembly comprising: a hub bearing; a hub coupled within the hub bearing to be rotatable; and a preload nut which is fastened to an inside of a bended forming unit in which one end of the hub is bended, and fixes the hub bearing toward the other end of the hub. The driving wheel axle assembly prevents an inner wheel from generating slip on the hub.

Description

An axle assembly for a driving wheel of vehicle

The present invention relates to a driving wheel axle assembly, and more particularly, to a driving wheel axle assembly disposed on each driving wheel of a vehicle and capable of providing a cleavage or plunging function while transmitting driving force in a wheel direction.

In general, an axle assembly including a knuckle, a hub, a hub bearing, a wheel disk, a constant velocity joint, and a drive shaft is provided on a driving wheel or a non-driving wheel of a vehicle.

Among them, the driving wheel axle assembly transmits power generated from the engine, the motor, or a combination thereof to the driving wheels, and also serves to support a load generated between the vehicle and the driving wheels.

In addition, the drive wheel axle assembly generally has a structure in which a hub bearing is coupled to the outside around a hub, a drive shaft is coupled to the inside, and a constant velocity joint is coupled to one side of the drive shaft. Further, the constant velocity joint is constituted by an outer ring, an inner ring, a ball disposed between the outer ring and the inner ring, and a cage for supporting the ball between the outer ring and the inner ring.

However, the drive wheel axle assembly has a problem in that the manufacturing cost is rapidly increased because the balls of the hub bearings in direct contact with the outer circumferential surface of the hub must be made of high-clean steel. In addition, in the drive wheel axle assembly, a problem that slip occurs in the inner ring provided to partially contact the ball during the configuration of the hub bearing has been pointed out. In addition, there is a possibility that the inner ring of the hub bearing may be lifted from the orbital forming part, and as the ball of the hub bearing and the ball of the constant velocity joint are disposed adjacently, the development of a technology that can prevent thermal deformation in the area where frictional heat overlaps is in need.

Korean Patent Publication No. 10-12224161 (registered on March 2, 2021)

The present invention is to solve such a problem, and more particularly, a drive wheel axle assembly capable of preventing the inner ring from slipping on the hub by providing a preload nut on the outer circumferential surface of the hub for providing a preload to the inner ring side of the hub bearing. It aims to provide

The present invention for performing the above object is a hub bearing; a hub coupled to be rotatably coupled within the hub bearing and a preload nut fastened inside a forming part in which one end of the hub is bent to fix the hub bearing in the direction of the other end of the hub; It provides a drive wheel axle assembly comprising a.

The preload nut may have a female screw formed on its inner circumferential surface to correspond to the male screw formed on the outer circumferential surface of the hub.

The preload nut has a head portion formed in a plurality of planes so that a tool can grip or pressurize when it is fastened on the female screw, and extends from one side of the head portion in the direction of the forming portion, and a boot fixing groove is formed on the outer circumferential surface. It may include an extension part that is formed, and a pressing part disposed on the other side of the head part to press the hub bearing.

The preload nut may be disposed to overlap at least a part or all of a movement region of the ball of the constant velocity joint along the axial direction of the shaft.

The hub bearing includes a pair of inner rings coupled to the outer circumferential surface of the hub, an outer ring disposed outside to face the pair of inner rings, and a plurality of balls interposed to support between the inner and outer rings, the inner ring The structures of the same shape are arranged to face each other symmetrically, so that the ends of each inner ring can be supported in contact with each other.

Further comprising a constant velocity joint provided on one inner side of the hub to transmit the power transmitted from the shaft in the direction of the hub, along the axial direction of the shaft, so as not to be spaced apart or overlap with each other in the area in which the balls of the hub bearing are arranged can be placed.

The driving wheel axle assembly may further include a boot installed to cover between the shafts from the boot fixing groove formed on the outer circumferential surface of the preload nut.

In a region adjacent to the preload nut and the forming portion, the preload nut may be formed to have an outer diameter that is at least equal to or greater than the bent outermost outer diameter of the forming portion so as not to interfere with the coupling of the boot.

According to the driving wheel axle assembly according to the embodiment of the present invention,

First, as the manufacturing division between hubs and hub bearings becomes clear, the division of disputed materials becomes clear when a problem occurs, and technology grafting becomes easier,

Second, since the preload nut can fix the inner ring of the hub bearing in a preloaded state, the slip of the inner ring can be prevented.

Third, the preload force to be formed on the inner ring can be adjusted by adjusting the force for tightening the preload nut within a set range, and it can be assembled to have a certain preload force,

Fourth, by preventing the ball of the constant velocity joint from overlapping with the ball of the hub bearing, the heat treatment region for strength reinforcement overlaps the hub, and the load due to heat treatment or the contact load by the ball is prevented from being concentrated. ,

Fifth, since it is not necessary to manufacture the inner ring of the hub bearing with expensive high-cleaning steel, there is an effect of reducing the cost.

1 is a perspective view illustrating a driving wheel axle assembly according to an embodiment of the present invention.
FIG. 2 is an exploded perspective view showing the driving wheel axle assembly shown in FIG. 1 separated; FIG.
Fig. 3 is a cross-sectional view showing a section II' of the drive wheel axle assembly shown in Fig. 1;
FIG. 4 is a partially enlarged view showing an enlarged area A of the driving wheel axle assembly shown in FIG. 3 .
5A is an enlarged front view of a preload nut of the driving wheel axle assembly shown in FIG. 2 ;
5B is an enlarged perspective view of a preload nut of the driving wheel axle assembly shown in FIG. 2 ;
FIG. 5C is an enlarged side view of a preload nut of the driving wheel axle assembly shown in FIG. 2 ;

Since the present invention may have various changes and may have various embodiments, specific embodiments will be illustrated and described in the drawings.

However, this is not intended to limit the present invention to specific embodiments, and it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention.

Terms including an ordinal number, such as first, second, etc., may be used to describe various elements, but the elements are not limited by the terms.

The above terms are used only for the purpose of distinguishing one component from another.

For example, without departing from the scope of the present invention, the second component may be referred to as the first component, and similarly, the first component may also be referred to as the second component.

and/or includes a combination of a plurality of related listed items or any of a plurality of related listed items.

When an element is referred to as being “connected” or “connected” to another element, it is understood that it may be directly connected or connected to the other element, but other elements may exist in between. it should be

On the other hand, when it is said that a certain element is "directly connected" or "directly connected" to another element, it should be understood that the other element does not exist in the middle.

The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention.

The singular expression includes the plural expression unless the context clearly dictates otherwise.

In the present application, terms such as “comprise” or “have” are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, but one or more other features It should be understood that this does not preclude the existence or addition of numbers, steps, operations, components, parts, or combinations thereof.

Hereinafter, the embodiment will be described in detail with reference to the accompanying drawings, but the same or corresponding components are given the same reference numerals regardless of reference numerals, and overlapping descriptions thereof will be omitted.

1 is a perspective view showing a driving wheel axle assembly according to an embodiment of the present invention, FIG. 2 is an exploded perspective view showing the driving wheel axle assembly shown in FIG. 1 separated, and FIG. 3 is an I-I of the driving wheel axle assembly shown in FIG. ' It is a cross-sectional view showing a cross-section.

1 and 2 , the driving wheel axle assembly 1 according to the embodiment of the present invention includes a hub 110 coupled to the inside of a knuckle 10 of a vehicle, and a shaft 20 disposed inside the hub 110 . ) from the constant velocity joint 120 that transmits power in the direction of the hub, and the hub bearing 130 coupled between the knuckle 10 and the hub 110 and the hub bearing 130 on the hub 110 to provide a preload Includes a preload nut (140).

First, the hub 110 is provided with a forming part 111 having one end bent, and a radially extending flange 112 is provided at the other end.

The forming part 111 is formed while one end of the hub 110 is bent in the circumferential direction through an orbital forming process. The forming part 111 is preferably formed after the hub bearing 130 and the preload nut 140 are coupled to the outer circumferential surface of the hub 110 . The forming unit 111 presses the preload nut 140 in the orbital forming process.

A plurality of fasteners 113 are fastened to the flange 112 so that a wheel disk (not shown) and a wheel (not shown) are coupled.

The hub 110 has a plurality of outer grooves 114 formed on the inner circumferential surface to which the constant velocity joint 120 is coupled.

The constant velocity joint 120 includes an inner ring 121 , a ball 122 , and a cage 123 , but may further include an outer groove 114 on the inner circumferential surface of the hub 110 . In this embodiment, a structure in which the outer groove 114 is integrally formed inside the hub 110 will be described as an example, and a structure coupled to each other in a separate configuration may be adopted. That is, the outer groove 114 inside the hub 110 may serve as an outer ring of a general constant velocity joint.

The cage 123 accommodates the ball 122 , and a window 124 for preventing the ball 122 from being separated is provided.

The balls 122 are accommodated in the space between the outer groove 114 of the hub 110 and the inner groove 125 of the inner ring 121, respectively, and furthermore, to be prevented from being separated by the window 124 of the cage 123. arrested

A plurality of balls 122 are provided (eg, between 6 and 12), and in the embodiment of the present invention, a structure in which 8 balls are provided will be described as an example.

An insertion hole 126 is provided inside the inner ring 121 , and a serration portion is provided on the inner surface of the insertion hole 126 to be toothed with the serration portion provided at the end of the shaft 20 .

In addition, since the outer groove 114 and the inner groove 125 are arranged around the ball 122, they are formed in a quantity corresponding to the quantity of the balls, respectively.

The hub 110 has a web 115 between the outer grooves 114 , and the inner ring 121 has a web 127 between the inner grooves 125 .

A cage 123 is disposed between the hub 110 and the inner ring 121 , and a window 124 for preventing the ball 122 from being separated while the ball 122 is accommodated in the cage 123 is between the web 128 . provided at regular intervals.

The boot 150 is coupled to the hub 110 so as to cover the inner ring 121, the balls 122 and the cage 123 from one end to one end of the shaft 20 in a state in which it is accommodated therein. Grease may be filled inside the hub 110 and the boot 150 . One side of the boot 150 is coupled to the outer circumferential surface of the preload nut 140 coupled to the outer circumferential surface of the hub 110 , and the other side is coupled to one end of the shaft 20 . A detailed coupling position of the boot 150 will be described later.

The outer groove 114 may be formed in a straight line on the inside of the hub 110 along the power transmission direction, and the inner groove 125 may be formed in a straight line on the outside of the inner ring 121 along the power transmission direction. Accordingly, a plunging operation may be performed at the same time as a notch is made between the hub 110 and the inner ring 121 . In addition, although not shown in the drawings, the outer groove may be applied to a constant velocity joint structure that is formed in a curve on the inside of the hub and is only involved in the cleavage.

In this configuration, when power is transmitted to the shaft 20, power is sequentially transmitted to the output shaft through the inner ring 121, the ball 122, and the hub 110, and the power is transmitted to the driving wheel side at a constant speed. there is.

In addition, the hub bearing 130 is coupled before the forming portion 111 is formed in the region between the flange 112 and the forming portion 111 of the hub 110 .

The hub bearing 130 includes an inner ring 131 , balls 132 , and an outer ring 133 .

The inner ring 131 of the hub bearing 130 includes a first inner ring 131a and a second inner ring 131b coupled to the outer circumferential surface of the hub 110 . The first inner ring 131a and the second inner ring 131b have the same structure in which one cross-section is approximately “L”-shaped, and the flange 112 rather than the forming part 111 so as to face each other on the outer circumferential surface of the hub 110 . connected adjacent to That is, the first inner ring 131a has a first ball track 131c formed on its outer circumferential surface, and the second inner ring 131b has a second ball track 131d formed on its outer circumferential surface, and the first ball track 131c and The second ball track 131d is arranged symmetrically between the first inner ring 131a and the second inner ring 131b so that the balls 132 accommodated in each are not separated to the outside. In this case, the horizontal ends of the first inner ring 131a and the second inner ring 131b are arranged to be in close contact with each other. Therefore, since the inner ring 131 can be used as the second inner ring 131b through the manufacturing process of the first inner ring 131a, manufacturing costs such as mold cost and assembly cost can be reduced.

In addition, the inner ring 131 is coupled to enable separation of the first inner ring 131a and the second inner ring 131b on the outer circumferential surface of the hub 110 . Of course, the hub bearing 130 itself may be separated on the outer circumferential surface of the hub 110 . Accordingly, there is an effect that replacement or repair of the hub bearing 130 is easy.

In addition, seals 135 are provided on the outside between the first inner ring 131a and the outer ring 134 and between the second inner ring 131b and the outer ring 134 , respectively.

The outer ring 134 is formed with an outer ball track 134a facing the first ball track 131c and the second ball track 131d. The outer ring is included in the hub bearing as a separate configuration and may be implemented in such a way that it is coupled to the coupling part of the knuckle.

That is, the outer ring 134 is provided with a first coupling flange 134b on the outer circumferential surface, an outer ball track 134a is formed therein, and is coupled to the ball 132 and the inner ring 131, the outer ring 134, the ball ( The hub bearing 130 to which 132 ) and the inner ring 131 are coupled may have a structure in which the first coupling flange 134b of the outer ring 134 and the second coupling flange 10a provided on the knuckle 10 are coupled. . In the embodiment of the present invention, the outer ring 134 is provided as a separate configuration, and the hub bearing has a structure in which the first coupling flange 134b of the outer ring 134 and the second coupling flange 10a of the knuckle 10 are coupled. The combination of 130 and the knuckle 10 will be described as an example.

Alternatively, the outer ring 134 may correspond to the inner circumferential surface of the coupling hole formed to be coupled to the hub 110 on the knuckle 10 . Accordingly, in the present embodiment, the outer ball track 134a is integrally formed so that the inner circumferential surface of the knuckle 10 serves as the outer ring of the hub bearing 130 , so that a separate outer ring configuration can be omitted.

4 is an enlarged partial view showing area A of the driving wheel axle assembly shown in FIG. 3 , FIG. 5A is an enlarged front view of the preload nut of the driving wheel axle assembly shown in FIG. 2 , and FIG. It is an enlarged perspective view of the preload nut of the driving wheel axle assembly shown, and FIG. 5C is an enlarged side view of the preload nut of the driving wheel axle assembly shown in FIG. 2 .

The preload nut 140 is coupled between the inner ring 131 of the hub bearing and the forming part 111 . More precisely, the preload nut 140 is coupled between the second inner ring 131b and the forming part 111 . The preload nut 140 prevents slippage of the inner race 131 between the second inner race 131b and the hub 110 by pressing the second inner race 131b in the other direction of the hub 110 .

Here, the preload nut 140 includes a head portion 141 , an extension portion 142 , and a pressing portion 143 .

The head portion 141 is an area in which at least a pair of facing surfaces are formed as a flat surface 144 , so that when the preload nut 140 is fastened, the tool grips or presses the flat surface to rotate it. The head 141 may be formed in a polygonal shape having at least an even number of planes of at least a square, like a kind of bolt head. In this embodiment, the outer surface of the head part 141 will be described as an octagonal shape as an example.

The extension part 142 is disposed to extend in the direction of the forming part 111 from one side of the head part 141 . The preload nut 140 has at least a female screw 145 formed on the inner circumferential surface of the head 141 and the extension 142, and a male screw 116 is formed on the outer circumferential surface of the hub 110 correspondingly to the female screw 145. The preload nut 140 is coupled to the hub 110 while the male screw 116 and the male screw 116 are engaged. Of course, a female thread may also be formed on the inner peripheral surface of the pressing part 143 .

On the outer peripheral surface of the extension part 142, a boot fixing groove 146 is formed inwardly along the circumferential direction. Therefore, the boot (see FIG. 3, 150) is coupled to the outer circumferential surface of the extension 142, and the band 151 is fastened in the direction of the boot fixing groove 146 on the outer circumferential surface of the boot 150 to fix the boot 150. can

The pressing part 143 is disposed in the direction of the hub bearing 130 from the other side of the head part 141 and is in contact with the side surface of the second inner ring 131b. Accordingly, when the preload nut 410 rotates, the preload can be continuously provided by the pressing part 143 pressing the second inner ring 131b. The pressing part 143 may be formed to protrude more at least to the outside than the head part 141 along the circumferential direction. That is, the pressing part 143 is provided in the shape of a disk, and the pressing part 143 is provided to extend further in the radial direction than the plane of the head part 141 .

The extension part 142 provides pressure to the preload nut 140 while the forming part 111 is bent by the orbital forming process, and this pressure may prevent the preload nut 140 from loosening. Of course, the preload nut 140 may be continuously provided with a preload by the forming unit 111 .

For example, the preload nut 140 may provide a preload having a torque in the set range to the hub bearing 130 by adjusting the torque coupled on the hub 110 to a set range. Of course, the torque of the preload nut 140 can be further tightened or loosened using a torque wrench to adjust the setting range. Accordingly, the preload nut 140 has an effect of providing a precise preload toward the hub bearing 130 .

In addition, as shown in FIG. 5B , the preload nut 140 protrudes more in the circumferential direction than the extension part 142 while the stepped part 147 is formed in the area where the planes 144 of the head part 141 are adjacent to each other. That is, the outer diameter of the extension part 142 is made at the same height as the center of the plane 144 of the head part 141 , and the step part 147 adjacent to both ends of the plane 144 of the head part 41 is extended. The corner portion of the polygon is implemented while protruding outward than the portion 142 . The regions 147 in which the planes 144 of the head part 141 are adjacent to each other can reinforce the strength of the preload nut 140 , thereby increasing structural stability.

And, the preload nut 140 is provided so that the outermost outer diameter of the extension portion 142 has a larger outer diameter than the outermost outer diameter of the forming portion (111). Of course, the outermost outer diameter of the extension portion 142 and the forming portion 111 may be provided to have the same size. In other words, in the orbital morphing process, the forming part 111 is disposed higher than the center line of the preload nut 140 , and is disposed lower than the outermost height of the preload nut 140 . This is to avoid interference between the boot 150 and the forming part 111 while the boot 150 is coupled to the outer circumferential surface of the extension part 142 .

A boot fixing groove 146 to which one side of the boot 150 is coupled is formed on the outer peripheral surface of the preload nut 140 . The boot 150 is at least partially inserted into the boot fixing groove 146 of the preload nut 140 , and the band 151 is coupled to press the boot 150 in the boot fixing groove 146 direction.

And, the ball 132 of the hub bearing 130 and the ball 122 of the constant velocity joint 120 are disposed so as not to overlap each other along the axial direction. In other words, the region A1 in which the balls 132 of the hub bearing 130 are arranged in the vertical direction and the region A2 in which the balls 122 of the constant velocity joint 120 are arranged in the vertical direction are a process in which the driving force is transmitted. Frictional heat is generated with each other around the outer circumferential surface of the hub 110, and when the balls 132 and 122 on both sides are positioned to overlap each other around the hub 110, heat treatment for strength reinforcement in the hub 110 As the regions overlap, the load due to the heat treatment may be concentrated, and since the contact load by the balls 132 and 122 is concentrated, it is preferable that the balls 132 and 122 on both sides do not overlap each other. Accordingly, since the balls 132 and 122 are disposed not to overlap each other, it is possible to solve the problem that the ball 132 of the hub bearing 130 must be manufactured from expensive high-clean steel.

Therefore, according to the driving wheel axle assembly according to the embodiment of the present invention, as the manufacturing division between the hub and the hub bearing becomes clear, the division of disputed materials becomes clear when a problem occurs, technology grafting becomes easy, and the inner ring of the hub bearing is preloaded with a nut. Since the inner ring can be fixed under the preload state, the slip of the inner ring can be prevented, the preload force to be formed on the inner ring can be adjusted by adjusting the tightening force of the preload nut within the set range, and it can be assembled to have a constant preload force, constant velocity By preventing the balls of the joint from overlapping with the balls of the hub bearing, the heat treatment region for strength reinforcement overlaps on the hub, and it is possible to prevent the concentration of the load due to heat treatment or the concentration of the contact load due to the ball. Since it is not necessary to manufacture the inner ring of the hub bearing with high-clean steel, there is an effect of reducing the cost.

In the above, specific embodiments have been shown and described to illustrate the technical idea of the present invention, but the present invention is not limited to the same configuration and operation as the specific embodiments as described above, and various modifications do not depart from the scope of the present invention. can be carried out within Accordingly, such modifications should be considered to fall within the scope of the present invention, and the scope of the present invention should be determined by the following claims.

1: Drive wheel axle assembly
110: hub
120: constant velocity joint
130: hub bearing
140: preload nut
141: head
142: extension
143: pressure part
150: boot
10: knuckle
20: drive shaft

Claims (8)

hub bearings;
a hub rotatably coupled within the hub bearing; and
a preload nut having one end of the hub fastened to the inside of the bent forming part to fix the hub bearing toward the other end of the hub; including,
The hub bearing includes a pair of inner rings coupled to the outer circumferential surface of the hub and disposed so that structures of the same shape are symmetrically opposed to each other,
The pair of inner rings provides a uniform preload in the direction of the other end of the hub by the preload nut,
Each of the pair of inner rings provides a distributed pressure with respect to the outer peripheral surface of the hub,
The forming part supports and presses the preload nut so that the preload nut is not loosened,
The preload nut includes a head portion formed of a plurality of planes having a polygonal shape so that a tool can grip or pressurize when fastened on the outer circumferential surface of the hub, and extending from one side of the head portion in the direction of the forming portion to the outer circumferential surface an extension portion having a boot fixing groove formed thereon, and a pressing portion disposed on the other side of the head portion to press the inner ring and extend in a radial direction,
The pressing part is provided in the form of a plate,
The pressing part is provided to extend further in the radial direction than the plane of the head part,
The hub bearing is
an outer ring disposed on the outside to face the pair of inner rings, and
A plurality of balls interposed to support each other between the inner ring and the outer ring,
Ends of each of the inner rings are supported in contact with each other,
Further comprising a constant velocity joint provided on one inner side of the hub to transmit the power transmitted from the shaft in the direction of the hub,
Along the axial direction of the shaft, the region in which the balls of the hub bearing are arranged is arranged so as not to be spaced apart or overlap with the region in which the balls of the constant velocity joint are arranged,
The preload nut is
A driving wheel axle assembly, characterized in that it is arranged to overlap at least a part or all of the movement area of the ball of the constant velocity joint along the axial direction of the shaft. The method according to claim 1,
The preload nut is
The driving wheel axle assembly, characterized in that the female screw is formed on the inner circumferential surface to correspond to the male screw formed on the outer circumferential surface of the hub. delete delete delete delete The method according to claim 1,
a boot installed to cover between the shafts from the boot fixing groove formed on the outer circumferential surface of the preload nut;
The drive wheel axle assembly further comprising a. 8. The method of claim 7,
In a region adjacent to the preload nut and the forming part, the bent outermost outer diameter of the forming part is at least half the height of the preload nut and is formed so as not to exceed the outermost height of the preload nut.

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