KR20220166522A - Corner module of drive axle - Google Patents

Abstract

The present invention relates to a corner module of a drive axle which reduces drag torque by removing a bearing inner seal of a wheel bearing and reduces frictional noise generated from a wrinkled portion of a boot. The introduced corner module of the drive axle comprises: a wheel bearing assembled to a wheel housing; a knuckle fixed to an outer ring of the wheel bearing; the boot in which a large diameter unit of one end is assembled to the knuckle; and a bearing seal unit assembled between a small diameter unit of the other end of the boot and the drive axle to prevent inflow of a foreign substance while limiting rotation of the boot.

Description

Corner module of drive axle {Corner module of drive axle}

The present invention relates to a drive axle assembly capable of reducing drag torque and improving fuel efficiency of a vehicle by removing a bearing inner seal of a wheel bearing and reducing frictional noise generated from a crease portion of a boot.

Integrated Drive Axle (IDA) is a structure in which the outer race of the drive shaft and the hub of the wheel bearing are integrated.

In other words, by integrating the functions of the wheel bearing and the drive shaft, the weight of the product is reduced as well as the product cost is reduced, and the cutting of the drive shaft is increased by reducing the joint center distance, while the wheel bearing PCD is increased to improve the lateral rigidity of the vehicle. There are advantages to this increase.

However, the increase in the size of the wheel bearing acts as a factor increasing the drag torque of the wheel bearing, and eventually adversely affects the fuel efficiency of the vehicle.

Accordingly, the drag torque of the wheel bearing may be reduced by changing the structure of the bearing inner seal responsible for sealing the wheel bearing.

However, since the bearing inner seal inserted between the outer ring and the inner ring of the wheel bearing is exposed to the outside of the boot, the sealing property of the bearing inner seal must be maintained at a certain level or higher to prevent inflow of foreign substances into the wheel bearing.

However, as the sealing property of the bearing inner seal increases, the drag torque also increases, so there is a limit to reducing the drag torque.

That is, since the bearing inner seal is inserted between the inner ring and the outer ring, the circumference of the bearing inner seal is formed to be relatively long, and thus, there is a disadvantage in that the drag torque increases due to the sealing action by the bearing inner seal.

In addition, as the boot rotates with the constant velocity joint, the creases of the boot are continuously folded and unfolded along the circumferential direction during full turn driving. There is also a problem that friction noise occurs due to falling off.

The matters described as the background art above are only for improving understanding of the background of the present invention, and should not be taken as an admission that they correspond to prior art already known to those skilled in the art.

JP 5868643 B2 JP 2007-315423 A

The present invention has been made to solve the above problems, and provides a drive axle assembly that reduces drag torque and improves fuel efficiency of a vehicle by removing the bearing inner seal of a wheel bearing.

An object of the present invention is to provide a drive axle assembly capable of reducing frictional noise generated from a crease of a boot.

A configuration of the present invention for achieving the above object is a wheel bearing assembled to a wheel housing; Knuckle fixed to the outer ring of the wheel bearing; a boot in which one end of the large-diameter portion is assembled to the knuckle; and a bearing seal unit assembled between the small diameter portion of the other end of the boot and the drive shaft to prevent the inflow of foreign substances while limiting the rotation of the boot.

An assembly hole is formed in the knuckle; The outer ring is fixed to the first inner section formed on the wheel housing side of the assembly hole; A boot may be assembled to a second inner section formed on the boot side of the assembly hole.

The large-diameter part of the boot is inserted into the second inner section; A band is fastened in an outer radial direction from the inner circumferential surface of the large diameter portion so that the boot can be fastened to the second inner section.

A boot fastening groove is formed along an inner circumferential surface of the second inner section; A band may be fastened to the boot fastening groove.

An end of the large-diameter portion of the boot may come into contact with an end of the wheel housing facing it.

An O-ring may be inserted between the first inner section and the outer ring.

A boot fastening part protrudes from the end of the second inner section toward the boot side; The large-diameter part of the boot is inserted into the boot fastening part; The boot may be fastened to the second inner section by fastening the band in the inner radial direction from the outer circumferential surface of the large diameter part.

A boot fastening groove is formed along an outer circumferential surface of the boot fastening portion; A band may be fastened to the boot fastening groove.

A grease seal may be used to seal between an end of the second inner section on the side of the wheel housing and the opposite wheel housing.

the grease seal is fixed to the end of the second inner section; A lip of the grease seal may contact an end of the wheel housing.

A portion connected between the inner circumferential surface of the first inner section and the inner circumferential surface of the second inner section may be formed with a predetermined gap between the wheel bearing and the wheel housing facing the same.

One end of the boot fastening ring is assembled to the second inner section; A large-diameter portion of the boot may be assembled to the other end of the boot fastening ring.

The boot fastening ring is configured by fixing a reinforcing ring to the outer diameter of the outer ring; A reinforcing ring is assembled to the second inner section; The large diameter part of the boot may be fixed to the inner diameter part of the outer ring.

Through the above problem solving means, the present invention covers the outer ring with a knuckle instead of a bearing inner seal that seals between the outer ring and the inner ring of the wheel bearing to prevent the inflow of foreign substances, thereby reducing the drag torque according to the sealing action of the bearing inner seal It has the effect of improving the fuel efficiency of the vehicle.

Moreover, since the boot does not rotate, the creases of the boot do not continuously fold and unfold along the circumferential direction in various driving situations including full-turn driving, preventing frictional noise that may occur as the creases contact and separate during driving. There is also an effect of

In addition, by strengthening the sealing property through the sealing structure provided between the knuckle and the wheel housing, the grease for the constant velocity joint is prevented from moving to the wheel bearing side, thereby preventing the grease for the constant velocity joint and the grease for the wheel bearing from being mixed. there is.

1 is a cross-sectional view showing a first embodiment structure for fastening a boot and a knuckle in a corner module of the present invention.
FIG. 2 is a view showing the wheel housing and boot assembly of FIG. 1 separated;
3 is an enlarged view of part 'A' of FIG. 1;
Figure 4 is a view showing the structure of the second embodiment for fastening the boot and the knuckle in the corner module of the present invention.
5 is an enlarged view of part 'B' of FIG. 4;
6 is a view showing a gap formed between a knuckle, a wheel housing, and a wheel bearing according to the present invention.
7 is a view showing a structure of a third embodiment for fastening a boot and a knuckle in a corner module of the present invention.
8 is an enlarged view of part 'C' of FIG. 7;
9 is a view showing a structure of a fourth embodiment in which a boot and a knuckle are fastened in a corner module of the present invention.

Specific structural or functional descriptions of the embodiments of the present invention disclosed in this specification or application are merely illustrated for the purpose of explaining the embodiments according to the present invention, and the embodiments according to the present invention may be implemented in various forms. It may be and should not be construed as being limited to the embodiments described in this specification or application.

Embodiments according to the present invention can apply various changes and can have various forms, so specific embodiments are illustrated in the drawings and described in detail in this specification or application. However, this is not intended to limit the embodiments according to the concept of the present invention to specific disclosures, and should be understood to include all modifications, equivalents, and substitutes included in the spirit and technical scope of the present invention.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The above terms are only for the purpose of distinguishing one component from another component, e.g., without departing from the scope of rights according to the concept of the present invention, a first component may be termed a second component, and similarly The second component may also be referred to as the first component.

It is understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, but other elements may exist in the middle. It should be. On the other hand, when an element is referred to as “directly connected” or “directly connected” to another element, it should be understood that no other element exists in the middle. Other expressions describing the relationship between elements, such as "between" and "directly between" or "adjacent to" and "directly adjacent to", etc., should be interpreted similarly.

Terms used in this specification are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as "comprise" or "having" are intended to designate that the described feature, number, step, operation, component, part, or combination thereof exists, but one or more other features or numbers However, it should be understood that it does not preclude the presence or addition of steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and unless explicitly defined herein, they are not interpreted in an ideal or excessively formal meaning. .

A preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

It is a cross-sectional view showing the structure of the first embodiment for fastening the boot 400 and the knuckle 300 in the corner module of the present invention.

Referring to the drawings, the corner module of the drive axle of the present invention is designed based on an integrated drive axle (IDA), and the outer ring 210 of the wheel bearing 200 is fixed to the knuckle 300 or the carrier. The ball 230 (or roller) and cage are assembled between the outer ring 210 and the inner ring 220 of the wheel bearing 200, and the wheel bearing 200 is formed on the outer circumferential surface of the integrated wheel housing 100. inserted

In addition, by performing an orbital forming process on the end portion 110 of the wheel housing 100 to form a shape in which the end portion 110 of the wheel housing 100 is rolled up in an outward direction, a preload is applied to the wheel bearing 200. is applied to fix the inner ring 220 to the wheel housing 100.

In addition, since the drive shaft 500 is connected to the inside of the wheel housing 100 through a constant velocity joint, the driving force of the power train is transmitted to the constant velocity joint through the drive shaft 500, and the constant velocity joint is The wheel housing 100 rotates while being flowed and cut.

In particular, according to the present invention, the boot assembly including the boot 400 is assembled between the outer ring 210 of the wheel bearing 200 and the drive shaft 500 in a state in which rotation is restricted.

Referring to Figures 1 and 2, the present invention is a wheel bearing 200 assembled to the wheel housing 100; A knuckle 300 fixed to the outer ring 210 of the wheel bearing 200; a boot 400 in which one end of the large-diameter portion 400a is assembled to the knuckle 300; and a bearing seal unit which is assembled between the drive shaft 500 and the small diameter portion 400b of the other end of the boot 400 to limit rotation of the boot 400 and prevent the inflow of foreign substances.

For example, the end of the knuckle 300 is assembled into a shape surrounding the outer ring 210 formed on the boot 400 side.

In addition, the bearing seal unit is assembled between the small diameter portion 400b of the boot 400 and the drive shaft 500 in a shape surrounding the drive shaft 500, so that the drive shaft 500 relative to the boot 400 Rotation is allowed, and thus the boot 400 is in a fixed state without rotating.

As described above, in the present invention, by covering between the outer ring 210 and the inner ring 220 of the wheel bearing 200 by the knuckle 300, external foreign substances are prevented from entering the inside of the wheel bearing 200, The bearing inner seal of is removed. Accordingly, the drag torque by the bearing inner seal is reduced to improve fuel efficiency.

Moreover, even if the constant velocity joint rotates, the boot 400 does not rotate, so that the creases of the boot 400 do not continuously fold and unfold along the circumferential direction in various driving situations including full-turn driving. Frictional noise generated when wrinkles contact and separate during driving is prevented.

In addition, FIG. 3 is an enlarged view of part 'A' in FIG. 1 .

As shown in the drawing, the present invention has an assembly hole 310 formed in the knuckle 300; The outer ring 210 is fixed to the first inner section 310a formed on the wheel housing 100 side of the assembly hole 310; The boot 400 is assembled in the second inner section 310b formed on the boot 400 side of the assembly hole 310.

For example, the inner diameter of the first inner section 310a is formed longer than the inner diameter of the second inner section 310b, so that a step is formed between the first inner section 310a and the second inner section 310b.

Accordingly, the outer circumferential surface of the outer ring 210 is assembled and fixed to the inner circumferential surface of the first inner section 310a having a long inner diameter, and the large diameter part of the boot 400 is attached to the inner circumferential surface of the second inner section 310b having a relatively short inner diameter. (400a) is assembled.

In particular, in the present invention, the large diameter portion 400a of the boot 400 is inserted into the second inner section 310b; The boot 400 is fastened to the second inner section 310b by fastening the band b in the outer radial direction from the inner circumferential surface of the large diameter portion 400a.

That is, by fastening the boot 400 and the knuckle 300 using the band (b), the assemblability of the boot 400 is improved, as well as the attachment and detachment of the boot 400 is easy, so the work according to replacement and repair will improve sexuality.

Furthermore, a boot fastening groove 312 is formed along the inner circumferential surface of the second inner section 310b; It becomes a structure in which the band (b) is fastened to the boot fastening groove 312.

For example, in a state in which the large diameter portion 400a of the boot 400 is seated in the boot fastening groove 312, the band b is fastened in the boot fastening groove 312, so that the large diameter portion 400a of the boot 400 ) is inserted into the boot fastening groove 312 and fastened in a pressed state. To this end, the width of the boot fastening groove 312 should be shorter than the width of the band (b).

That is, as the large-diameter portion 400a of the boot 400 is fastened into the boot fastening groove 312, the fastening force and assembly of the boot 400 are further improved.

In addition, referring to FIG. 3 , the present invention has a structure in which the end of the large diameter portion 400a of the boot 400 is in contact with the end of the wheel housing 100 facing it.

For example, the large-diameter portion 400a of the boot 400 is in contact with the orbitally formed end of the wheel housing 100 .

Therefore, the constant velocity joint grease inside the wheel housing 100 is prevented from moving toward the wheel bearing 200, thereby preventing mixing of the constant velocity joint grease and the wheel bearing grease.

In addition, in the present invention, an O-ring (O) may be inserted between the first inner section (310a) and the outer ring (210).

For example, an O-ring (O) is inserted between the inner circumferential surface of the first inner section 310a of the knuckle 300 and the outer circumferential surface of the outer ring 210, and the first inner section 310a and/or It becomes a structure in which a ring groove is formed in any one or more of the outer ring 210.

Also, a sealant may be applied to the inner circumferential surface of the first inner section 310a and the outer circumferential surface of the outer ring 210 .

Accordingly, sealing property between the knuckle 300 and the outer ring 210 may be enhanced to prevent leakage of wheel bearing grease inside the wheel bearing 200 .

Meanwhile, referring to FIGS. 1 and 2 , the bearing seal unit of the present invention includes a shaft bearing 600 assembled between the small diameter portion 400b of the boot 400 and the drive shaft 500; A shaft seal 700 assembled between the small diameter portion 400b of the boot 400 and the drive shaft 500 at a position closer to the end of the small diameter portion 400b of the boot 400 than the shaft bearing 600; to be composed.

For example, the shaft bearing 600 may be a bearing such as a ball bearing or a needle bearing. The inner ring 220 of the shaft bearing 600 is supported by the drive shaft 500, and the outer ring of the shaft bearing 600 is supported. 210 is supported by the small diameter portion 400b of the boot 400.

In addition, a shaft seal 700 is installed inside the end of the small diameter portion 400b of the boot 400 in a shape surrounding the drive shaft 500 to prevent foreign substances from entering the shaft bearing 600 and the boot 400. will block

However, although the drag torque is affected by the shaft seal 700, due to the location characteristics of the shaft seal 700 provided on the drive shaft 500, the shaft seal 700 is a bearing mounted on the wheel bearing 200. Compared to the inner seal, the length of the circumference is relatively short. Therefore, compared to the bearing inner seal, the level of increase in drag torque is not large, so that the fuel efficiency of the vehicle is not adversely affected.

On the other hand, Figure 4 is a view showing the structure of the second embodiment for fastening the boot 400 and the knuckle 300 in the corner module of the present invention, Figure 5 is an enlarged view of the 'B' part of FIG. to be.

Referring to the drawing, a boot fastening portion 314 is formed protruding from the end of the second inner section 310b toward the boot 400 side; The large-diameter portion 400a of the boot 400 is inserted into the boot fastening portion 314; The boot 400 may be fastened to the second inner section 310b by fastening the band b in the inner radial direction from the outer circumferential surface of the large diameter portion 400a.

For example, the inner circumferential surface of the large-diameter portion 400a of the boot 400 is assembled to the outer circumferential surface of the end of the second inner section 310b toward the side of the boot 400, and in this state, the boot 400 is held by the band b. The neck portion 400a is fastened to the second inner section 310b.

In this way, by fastening the boot 400 and the knuckle 300 using the band (b), assemblability of the boot 400 is improved, and in particular, the band (b) is fastened to the outside of the boot 400. Attachment and detachment of the boot 400 is easy to improve workability in replacement and repair.

Furthermore, according to the present invention, a boot fastening groove 312 is formed along the outer circumferential surface of the boot fastening portion 314; A band (b) may be fastened to the boot fastening groove 312 .

For example, in a state in which the large diameter portion 400a of the boot 400 is seated in the boot fastening groove 312, the band b is fastened in the boot fastening groove 312, so that the large diameter portion 400a of the boot 400 ) is inserted into the boot fastening groove 312 and fastened in a pressed state. To this end, the width of the boot fastening groove 312 should be shorter than the width of the band (b).

That is, as the large-diameter portion 400a of the boot 400 is fastened into the boot fastening groove 312, the fastening force and assembly of the boot 400 are further improved.

In addition, as shown in FIG. 5 , a grease seal 320 may seal between the end of the second inner section 310b on the side of the wheel housing 100 and the opposite wheel housing 100 .

Specifically, the grease seal 320 is fixed to the end of the second inner section 310b; The lip portion 322 of the grease seal 320 is in contact with the end of the wheel housing 100.

For example, the lip portion 322 of the grease seal 320 is in contact with the orbitally formed end of the wheel housing 100 .

Therefore, the constant velocity joint grease inside the wheel housing 100 is prevented from moving toward the wheel bearing 200, thereby preventing mixing of the constant velocity joint grease and the wheel bearing grease.

In addition, FIG. 6 is a view showing a gap g formed between the knuckle 300, the wheel housing 100, and the wheel bearing 200 according to the present invention.

Referring to the drawing, the part connected between the inner circumferential surface of the first inner section 310a and the inner circumferential surface of the second inner section 310b is a predetermined gap (g) between the wheel bearing 200 and the wheel housing 100 facing the same. can be formed with

For example, the orbitally processed end of the wheel housing 100 is rolled up in an outward direction and is formed in a shape that preloads the inner ring 220 of the wheel bearing 200, and the first inner section 310a and the second inner section 310a facing it. A maze structure is formed by forming a stepped gap between the inner sections 310b.

Therefore, the constant velocity joint grease inside the wheel housing 100 is prevented from moving toward the wheel bearing 200, thereby preventing mixing of the constant velocity joint grease and the wheel bearing grease.

Meanwhile, FIG. 7 is a view showing the structure of the third embodiment for fastening the boot 400 and the knuckle 300 in the corner module of the present invention, and FIG. 8 is an enlarged view of the 'C' part of FIG. 7 to be.

Referring to the drawings, one end of the boot fastening ring 410 is assembled to the second inner section 310b; The large-diameter portion 400a of the boot 400 may be assembled to the other end of the boot fastening ring 410 .

For example, both ends of the boot fastening ring 410 are assembled to the inner circumferential surface of the second inner section 310b and the large diameter portion 400a of the boot 400.

At this time, one end of the boot fastening ring 410 can be press-fitted to the inner circumferential surface of the second inner section 310b, and an additional O-ring (O) is applied or a sealant is applied to form the boot fastening ring 410 and the knuckle ( 300) and enhances the sealing property.

In addition, the other end of the boot fastening ring 410 is fastened to the large-diameter portion 400a of the boot 400 by the band b to improve the fastening force between the boot fastening ring 410 and the boot 400. .

9 is a view showing a structure of a fourth embodiment in which the boot 400 and the knuckle 300 are fastened in the corner module of the present invention.

Referring to the drawings, the boot fastening ring 410 is configured by fixing the reinforcing ring 430 to the outer diameter portion 420a of the outer ring 420.

Accordingly, a reinforcing ring 430 is assembled to the second inner section 310b; The large diameter portion 400a of the boot 400 is fixed to the inner diameter portion 420b of the outer ring 420.

That is, the boot fastening ring 410 is configured to include the outer ring 420 and the reinforcing ring 430, and the reinforcing ring 430 made of steel is press-fitted to the inner circumferential surface of the second inner section 310b, and the boot The outer ring 420 is fixed to the inside of the large diameter portion 400a of the 400 in an inserted form.

At this time, an O-ring (O) is additionally applied between the reinforcing ring 430 and the inner circumferential surface of the second inner section 310b, or a sealant is applied to improve assembly between the reinforcing ring 430 and the knuckle 300. , which enhances the sealing properties.

As described above, the present invention covers the outer ring 210 with the knuckle 300 instead of the bearing inner seal that seals between the outer ring 210 and the inner ring 220 of the wheel bearing 200 to prevent foreign substances from entering the bearing, The fuel efficiency of the vehicle is improved by reducing the drag torque according to the sealing action of the inner seal.

Moreover, since the boot 400 does not rotate, the creases of the boot 400 do not continuously fold and unfold along the circumferential direction in various driving situations including full-turn driving, which may occur as the wrinkles contact and separate during driving. This will prevent possible frictional noise.

In addition, by strengthening the sealing property through the sealing structure provided between the knuckle 300 and the wheel housing 100, the grease for the constant velocity joint is prevented from moving to the wheel bearing 200 side, so that the grease for the constant velocity joint and the wheel bearing This will prevent the grease from mixing.

On the other hand, although the present invention has been described in detail only for the specific examples described above, it is obvious to those skilled in the art that various changes and modifications are possible within the scope of the technical idea of the present invention, and it is natural that these changes and modifications fall within the scope of the appended claims. .

100: wheel housing
110: end
200: wheel bearing
210: outer ring
220: inner ring
230: ball
300: Knuckle
310: assembly hole
310a: first inner section
310b: second inner section
312: boot fastening groove
314: boot fastening part
320: grease seal
322: lip
400: boot
400a: large diameter
400b: small diameter
410: boot fastening ring
420: outer ring
420a: outer diameter
420b: inner diameter
430: reinforcement ring
500: drive shaft
600: shaft bearing
700: shaft seal
b: band
g : Gap
O: O-ring

Claims (13)

Wheel bearings assembled to the wheel housing;
Knuckle fixed to the outer ring of the wheel bearing;
a boot in which one end of the large-diameter portion is assembled to the knuckle; and
A corner module of a drive axle comprising: a bearing seal unit assembled between the small diameter part of the other end of the boot and the drive shaft to prevent the inflow of foreign substances while limiting the rotation of the boot. The method of claim 1,
An assembly hole is formed in the knuckle;
The outer ring is fixed to the first inner section formed on the wheel housing side of the assembly hole;
The corner module of the drive axle, characterized in that the boot is assembled in the second inner section formed on the boot side of the assembly hole. The method of claim 2,
The large-diameter part of the boot is inserted into the second inner section;
The corner module of the drive axle, characterized in that the boot is fastened to the second inner section by fastening the band in the outer radial direction from the inner circumferential surface of the large diameter part. The method of claim 3,
A boot fastening groove is formed along an inner circumferential surface of the second inner section;
Corner module of the drive axle, characterized in that the band is fastened to the boot fastening groove. The method of claim 2,
The corner module of the drive axle, characterized in that the large diameter end of the boot is in contact with the end of the wheel housing facing it. The method of claim 2,
A corner module of a drive axle, characterized in that an O-ring is inserted between the first inner section and the outer ring. The method of claim 2,
A boot fastening part protrudes from the end of the second inner section toward the boot side;
The large-diameter part of the boot is inserted into the boot fastening part;
The corner module of the drive axle, characterized in that the boot is fastened to the second inner section by fastening the band in the inner radial direction from the outer circumferential surface of the large diameter part. The method of claim 7,
A boot fastening groove is formed along an outer circumferential surface of the boot fastening portion;
Corner module of the drive axle, characterized in that the band is fastened to the boot fastening groove. The method of claim 2,
The corner module of the drive axle, characterized in that between the wheel housing side end of the second inner section and the wheel housing facing it is sealed by a grease seal. The method of claim 9,
the grease seal is fixed to the end of the second inner section;
The corner module of the drive axle, characterized in that the lip of the grease seal is in contact with the end of the wheel housing. The method of claim 2,
The corner module of the drive axle, characterized in that the part connected between the inner circumferential surface of the first inner section and the inner circumferential surface of the second inner section is formed with a predetermined gap between the wheel bearing and the wheel housing facing it. The method of claim 2,
One end of the boot fastening ring is assembled to the second inner section;
The corner module of the drive axle, characterized in that the large diameter part of the boot is assembled to the other end of the boot fastening ring. The method of claim 12,
The boot fastening ring is configured by fixing a reinforcing ring to the outer diameter of the outer ring;
A reinforcing ring is assembled to the second inner section;
The corner module of the drive axle, characterized in that the large diameter portion of the boot is fixed to the inner diameter portion of the outer ring.

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