KR20220157766A - Tire for electric vehicles - Google Patents

Abstract

The present invention relates to a tire for an electric vehicle. The tire for the electric vehicle according to one embodiment of the present invention comprises: a tread unit including an area in contact with the ground surface; a sidewall unit extending from both sides of the tread unit; a belt layer disposed under the tread unit; a body ply disposed under the belt layer; and an insertion layer which is disposed between the belt layer and the body ply, and presses the tire outward to increase the contact area between the tread unit and the ground surface. Provided is the tire for the electric vehicle including the insertion layer.

Description

Tires for electric vehicles {TIRE FOR ELECTRIC VEHICLES}

The present invention relates to a tire for an electric vehicle, and more particularly, to a tire for an electric vehicle including an insert layer.

Vehicles driven by users are composed of many parts, and among them, tires have a great influence on the operation of the vehicle, and in particular, can be said to be one of the key parts for securing the user's safety.

In particular, due to the development of the industry, the movement of logistics increases, the amount of movement due to the increase in personal workload, etc., and the amount of automobile operation due to the increase in family life tends to increase.

On the other hand, interest in electric vehicles driven by motors has recently increased in vehicles equipped with existing internal combustion engines. In general, the weight of an electric vehicle is heavier than that of a conventional internal combustion engine vehicle due to the weight of a battery. Accordingly, in the case of electric vehicles, various methods are used to improve fuel efficiency, such as mounting tires with improved fuel efficiency.

Tires mounted on electric vehicles are characterized by being designed and produced to have low rolling resistance, as fuel efficiency is required to be improved according to the above-mentioned reasons and eco-friendly market demands. In order to reduce the rolling resistance of the tire, it is necessary to reduce the air resistance of the tire surface and reduce the tire's repeated deformation. ) type of tire shape.

However, a tire for an electric vehicle having such a shape has a problem in that the contact area is reduced, which negatively affects riding and handling performance, and the stability and durability of the tire may be weakened.

The above-described background art is technical information that the inventor possessed for derivation of the present invention or acquired during the derivation process of the present invention, and cannot necessarily be said to be known art disclosed to the general public prior to filing the present invention.

An object of the present invention is to provide a tire for an electric vehicle including an insertion layer to compensate for a decrease in the contact area of the tire.

However, these problems are exemplary, and the problem to be solved by the present invention is not limited thereto.

A tire for an electric vehicle according to an embodiment of the present invention includes a tread portion including a region in contact with the ground, sidewall portions extending from both sides of the tread portion, a belt layer disposed under the tread portion, and disposed below the belt layer a body ply, and an insertion layer disposed between the belt layer and the body ply and pressing the tire outward to increase a contact area between the tread and the ground.

In the tire for an electric vehicle according to an embodiment of the present invention, the sidewall portion includes a first sidewall on one side and a second sidewall on the other side, and the insertion layer is formed at a junction between the first sidewall and the tread portion. It may be arranged to extend to a junction between the second sidewall and the tread part.

In the tire for an electric vehicle according to an embodiment of the present invention, one end of the insertion layer is disposed to cover the interface between the tread and the first sidewall, and the other end covers the interface between the tread and the second sidewall. It can be arranged to cover.

In the tire for an electric vehicle according to an embodiment of the present invention, the insertion layer extends along any one of a body portion having a first curvature toward the tread portion and the sidewall at one end of the body portion, and has a second curvature. It may include a first cover part having a first cover part and a second cover part extending along the other one of the sidewalls from the other end of the main body part and having a third curvature.

In the tire for an electric vehicle according to an embodiment of the present invention, the second curvature may be different from the third curvature.

In the tire for an electric vehicle according to an embodiment of the present invention, the thickness of the body portion may decrease toward the outside from the center in the width direction of the tire.

In the tire for an electric vehicle according to an embodiment of the present invention, the modulus of the insertion layer may be greater than the modulus of the sidewall portion.

In the tire for an electric vehicle according to an embodiment of the present invention, the modulus of the insertion layer may be greater than 1 time and less than 1.5 times the modulus of the sidewall portion.

In the tire for an electric vehicle according to an embodiment of the present invention, the width of the insertion layer in the tire width direction may be greater than that of the belt layer.

In the tire for an electric vehicle according to an embodiment of the present invention, the thickness of the insertion layer may be thinner than the thickness of the belt layer.

The tire for an electric vehicle according to an embodiment of the present invention further includes a sidewall reinforcing layer including a first reinforcing part disposed on the upper part of the first cover part and a second reinforcing part disposed on the upper part of the second cover part. can

Other aspects, features, and advantages other than those described above will become clear from the detailed description, claims, and drawings for carrying out the invention below.

A tire for an electric vehicle according to an embodiment of the present invention may include an insertion layer to increase a contact area between a tread portion and the ground, thereby improving riding and handling performance.

In addition, the insertion layer can cover from the first sidewall to the second sidewall, so that the rigidity of the junction of the tread part and the sidewall part can be further strengthened.

In addition, the curvature of both ends of the insert layer can be arranged to be different, so that it can correspond to the required stiffness and contact area of the tire in the vehicle inward and outward directions.

In addition, since the modulus of the insertion layer is greater than the modulus of the sidewall portion, the stiffness of the tire can be enhanced and the sidewall portion can be supported.

The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

1 is a cross-sectional view showing a cut surface of a tire for an electric vehicle according to an embodiment of the present invention.
2 is a conceptual diagram showing a comparison of the contact area of a tire for an electric vehicle and a general tire according to an embodiment of the present invention.
3 is a cross-sectional view showing an insertion layer according to an embodiment of the present invention.
4 is a cross-sectional view showing the tire 10 for an electric vehicle further including a sidewall reinforcing layer 950 according to an embodiment of the present invention.

Since the present invention can apply various transformations and have various embodiments, specific embodiments will be illustrated in the drawings and described in detail in the description of the invention. However, this is not intended to limit the present invention to specific embodiments, and should be understood to include all conversions, equivalents, or substitutes included in the spirit and scope of the present invention. In describing the present invention, even if shown in different embodiments, the same identification numbers are used for the same components.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, and when describing with reference to the drawings, the same or corresponding components are assigned the same reference numerals, and overlapping descriptions thereof will be omitted. .

In the following embodiments, terms such as first and second are used for the purpose of distinguishing one component from another component without limiting meaning.

In the following examples, expressions in the singular number include plural expressions unless the context clearly dictates otherwise.

In the following embodiments, terms such as include or have mean that features or components described in the specification exist, and do not preclude the possibility that one or more other features or components may be added.

In the drawings, the size of components may be exaggerated or reduced for convenience of description. For example, since the size and thickness of each component shown in the drawings are arbitrarily shown for convenience of description, the present invention is not necessarily limited to the illustrated bar.

In the following embodiments, the x-axis, y-axis, and z-axis are not limited to the three axes of the Cartesian coordinate system, and may be interpreted in a broad sense including these. For example, the x-axis, y-axis, and z-axis may be orthogonal to each other, but may refer to different directions that are not orthogonal to each other.

When an embodiment is otherwise implementable, a specific process sequence may be performed differently from the described sequence. For example, two processes described in succession may be performed substantially simultaneously, or may be performed in an order reverse to the order described.

Terms used in this application are only used to describe specific embodiments, and are not intended to limit the present invention. In this application, the terms "include" or "have" are intended to designate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, but one or more other features It should be understood that the presence or addition of numbers, steps, operations, components, parts, or combinations thereof is not precluded.

Hereinafter, a tire 10 for an electric vehicle according to an embodiment of the present invention will be described with reference to the drawings.

1 is a cross-sectional view showing a cut surface of a tire 10 for an electric vehicle according to an embodiment of the present invention, and FIG. 3 is a cross-sectional view showing an insertion layer 900 according to an embodiment of the present invention.

Referring to FIG. 1 , the tire 10 for an electric vehicle may include a tread portion 100 and sidewall portions 200 extending from both sides of the tread portion 100 . In addition, the tire 10 for an electric vehicle includes a bead portion 300 disposed at each end of the sidewall portion 200, a body ply 400 located under the tread portion 100, a belt layer 500, and a belt layer ( A cap ply 600 disposed above the 500 may be further included. In addition, the tire 10 for an electric vehicle may include an inner liner 700 positioned inside the tread portion 100 and the sidewall portion 200 to maintain the internal air pressure of the tire 10 .

The tread unit 100 may have a tread block TB partitioned by a plurality of grooves 150 . The tread block TB is a part that comes into contact with the ground during driving of the vehicle, and may be partitioned by a longitudinal groove formed along the circumferential direction of the tire 10 and a transverse groove formed along the width direction of the tire 10. have. The tread part 100 is made of a thick rubber layer and transmits driving force and braking force of the vehicle to the ground.

Sipes (S) may be included on the surface of the tread block (TB) to improve steering stability, traction, and braking performance. The sipe S is formed in the tread block TB and may be a groove having a smaller size than the groove. The sipes S may increase the driving force and braking force of the tire 10 by absorbing moisture and breaking the water film when driving on a wet road surface.

The sidewall portion 200 is located between the tread portion 100 and the bead portion 300 of the tire 10, and can improve ride comfort through flexion and extension movements. The sidewall portion 200 is connected to the tread portion 100 to support a load of a vehicle or the like. In addition, the sidewall portion 200 can withstand repeated contraction and expansion while driving a vehicle and absorb shock.

The bead part 300 is disposed at an end of the sidewall part 200 and serves to mount the tire 10 to the rim R. The bead unit 300 may include a bead core 310 and a bead filler 320 .

The bead core 310 is disposed under the bead filler 320 and may be formed by twisting a plurality of rubber-coated steel bead cords (wires).

The bead filler 320 is a rubber filler attached to one side of the bead core 310 and serves to reinforce the bead core 310 . In one embodiment, the bead filler 320 may be formed of a plurality of rubber fillers having different physical properties.

The body ply 400 extends along the tread portion 100 , the sidewall portion 200 , and the bead portion 300 to form the skeleton of the tire 10 . The body ply 400 may have a structure in which a tire cord is included inside a certain rubber component.

The body ply 400 is turned up in the bead portion 300 to create an inner space surrounded by the body ply 400, and the bead core 310 and the bead filler 320 are formed in the inner space. can be placed.

The body ply 400 may be formed by overlapping a plurality of cord papers made of high-strength fiber organic materials such as steel, polyester, or rayon, and then coating them with rubber and rolling them. Specifically, the body ply 400 may include at least one rubber component selected from the group consisting of synthetic rubber and natural rubber, and may include at least one tire cord. As the tire cord, various natural fibers or rayon, nylon, polyester, and Kevlar may be used, and a steel cord formed by twisting a plurality of thin wires may also be used.

The belt layer 500 may improve durability of the tire 10 and form a skeleton. In addition, the belt layer 500 serves to mitigate external impact and maintain a wide contact surface of the tread unit 100 to secure driving stability. The belt layer 500 is disposed below the tread portion 100 and may be formed by rolling by coating a plurality of belt cords (not shown) made of steel or organic fibers with rubber.

The belt layer 500 may be provided in plurality. For example, a first belt layer 510 disposed above the inner liner 700 and a second belt layer 520 disposed above the first belt layer 510 may be provided.

The cap ply 600 is disposed between the tread portion 100 and the belt layer 500. The cap ply 600 is a special cord paper attached to the belt layer 500 and can improve the driving performance of the tire 10. The cap ply 600 may include, for example, polyester synthetic fiber. It is possible to secure driving stability by minimizing movement.

The inner liner 700 may be disposed inside the tire 10 to prevent air leakage and maintain air pressure in the tire 10 . The inner liner 700 may be formed of a rubber layer having excellent sealing properties. For example, the inner liner 700 may be made of butyl rubber having a high density.

The inner liner 700 may be disposed inside the body ply 400 and extend to the bead part 300 . The inner liner 700 may contact one surface of the body ply 400, and both ends may contact the bead portion 300.

Referring back to FIG. 1 , the insertion layer 900 may be disposed between the belt layer 500 and the body ply 400 . The insertion layer 900 may be disposed between the belt layer 500 and the body ply 400 and extend along the circumferential direction of the tire 10 to form an annular shape. The insertion layer 900 supplements the rigidity of the tread part 100 and the sidewall part 200 so that the tread part 100 expands the contact area with the ground, and in particular, can press the sidewall part 200 outward. .

The insertion layer 900 may be disposed between the sidewall parts 200 in the width direction of the tire. That is, the sidewall portion 200 includes a first sidewall 210 on one side and a second sidewall 220 on the other side, and the insertion layer 900 extends from the first sidewall 210 to the tread portion 100. It may have a width extending to the second sidewall 220 across the .

Accordingly, the insertion layer 900 can supplement a phenomenon in which the contact area of the tread unit 100 decreases as the tire 10 for an electric vehicle is generally formed in a narrow-and-tall type. Since the insertion layer 900 is disposed under not only the tread part 100 but also the sidewall part 200, specifically the first sidewall 210 and the second sidewall 220, the sidewall part 200 is supported and driven. It is possible to maintain the shape of the sidewall portion 200 even in the middle. Since the tire 10 for an electric vehicle generally has difficulty maintaining the shape of the sidewall portion 200 during driving, the contact area is reduced, so the insertion layer 900 can compensate for this.

In one embodiment, the insertion layer 900 may be disposed to extend from a junction between the first sidewall 210 and the tread portion 100 to a junction between the second sidewall 220 and the tread portion 100 . A junction between the tread portion 100 and the sidewall portion 200, a so-called mold parting line, may be vulnerable to bending due to driving of the tire 10 for an electric vehicle. Accordingly, the insertion layer 900 may extend between the joint portion of the sidewall portion 200 and the tread portion 100 to reinforce the joint portion.

In one embodiment, one end of the insertion layer 900 is disposed to cover the interface between the tread portion 100 and the first sidewall 210, and the other end covers the interface between the tread portion 100 and the second sidewall 220. It can be arranged to cover. That is, one end of the insertion layer 900 supplements the rigidity at the bottom of the interface between the tread part 100 and the first sidewall 210, and the other end of the insertion layer 900 connects the tread part 100 and the second sidewall. The lower part of the boundary surface of the wall 220 may supplement rigidity. Accordingly, it is possible to cover and support the interface between the tread part 100 and the sidewall part 200, which may be relatively weak.

Tires for electric vehicles generally use high air pressure, which increases vertical stiffness and reduces the contact area. In the tire 10 for an electric vehicle according to the present invention, the insertion layer 900 is disposed as described above, thereby further strengthening the body ply 400 to improve the contact area of the tire 10 and improve riding and handling performance. can In addition, compared to the general tire shown in FIG. 2A, like the tire 10 according to the present invention shown in FIG. 2B, the sidewall part 200 is strongly supported to maintain its shape and secure a contact area.

At this time, in one embodiment, the modulus of the insertion layer 900 may be greater than the modulus of the sidewall portion 200 . As a result, the insertion layer 900 strongly supports the sidewall portion 200 as well as the tread portion 100 and prevents the sidewall portion 200 from flexing as shown in FIG. 2B to secure the contact area of the tire 10. have.

In one embodiment, the modulus of the insertion layer 900 may be larger than 1 times and smaller than 1.5 times the modulus of the sidewall portion 200 . The modulus of the insertion layer 900 must exceed one time the modulus of the sidewall portion 200 to support the sidewall portion 200 and maintain its shape. In addition, the modulus of the insertion layer 900 should be less than 1.5 times the modulus of the sidewall portion 200 to prevent the sidewall portion 200 from being hindered by excessive rigidity.

Referring to FIG. 3 , the insertion layer 900 according to an embodiment of the present invention may include a body portion 910 having a first curvature toward the tread portion 100 . The body portion 910 is a portion of the insert layer 900 disposed under the tread portion 100 to cover the tread portion 100 .

In addition, the insertion layer 900 extends along any one of the sidewalls 210 and 220 from one end of the body portion 910, and the other end of the first cover portion 920 and the body portion 910 having a second curvature. may include a second cover part 930 extending along the other one of the sidewalls 210 and 220 and having a third curvature.

For example, the first cover part 920 may extend along the first sidewall 210 and the second cover part 930 may extend along the second sidewall 220 . The first cover part 920 and the second cover part 930 may cover the first sidewall 210 and the second sidewall 220 , respectively.

The body portion 910, the first cover portion 920, and the second cover portion 930 reinforce the tread portion 100 and the sidewall portion 200 to maintain their shape, thereby increasing the contact area of the tire 10. can improve

The body portion 910 may be formed to have a first curvature, and the first curvature may be formed to have the same curvature as that of the body ply 400 . Accordingly, the body part 910 is closely attached to the upper surface of the body ply 400 without being spaced apart, so that the body ply 400 can be further strengthened.

The first cover part 920 is formed to have a second curvature and the second cover part 930 is formed to have a third curvature, and the second curvature and the third curvature may be formed to be different from each other.

In one embodiment, the first cover part 920 may be a side adjacent to the mounting direction of the tire 10 in the tire 10 for an electric vehicle, and the second cover part 930 is the tire 10 in the tire 10 for an electric vehicle. ) and the side distal to the mounting direction. At this time, the second curvature and the third curvature may be different from each other to form a curvature suitable for each side of the tire 10 for an electric vehicle. For example, the second curvature may be greater than the third curvature in consideration of the fact that the load burden of the second cover part 930 distal from the mounting direction of the tire 10 in the tire 10 for an electric vehicle is greater. However, it is not limited thereto, and the second curvature may be smaller than the third curvature, and various combinations of the second curvature and the third curvature may be possible according to the required performance of the tire 10 for an electric vehicle.

Since the tire 10 for an electric vehicle according to the present invention is formed so that the second curvature and the third curvature are different, the contact area can be improved by considering the state of the tire 10 during driving.

In one embodiment, the thickness of the body portion 910 may become thinner toward the outside from the center in the width direction of the tire 10 . That is, the thickness of the center of the body portion 910 is the thickest and the thickness of the body portion 910 may decrease toward the outside in the width direction of the tire 10 . This can strengthen the rigidity of the tread part 100 in consideration of the load that can be concentrated on the center of the tire 10, thereby preventing the tire 10 from bending and improving the contact area.

The width of the insertion layer 900 according to an embodiment of the present invention in the tire width direction may be greater than that of the belt layer 500 . In general, when the width of the belt layer 500 is formed larger than the width of the tread portion 100 in order to secure a ground contact area in an electric vehicle tire, it may be advantageous in terms of durability, but the weight increases and the rolling resistance is formed to increase fuel efficiency. Performance may deteriorate. In the tire 10 for an electric vehicle according to the present invention, durability can be improved by arranging the insertion layer 900 having a width greater than that of the belt layer 500 without increasing the width of the belt layer 500 .

In one embodiment, the thickness of the insertion layer 900 may be smaller than the thickness of the belt layer 500 . Accordingly, the insertion layer 900 is suitable for a function of supplementing stiffness for improving the contact area in the width direction of the tire 10 for an electric vehicle, while minimizing an effect such as weight increase.

4 is a cross-sectional view showing the tire 10 for an electric vehicle further including a sidewall reinforcing layer 950 according to an embodiment of the present invention.

Referring to FIG. 4 , the tire 10 for an electric vehicle according to an embodiment of the present invention may further include a sidewall reinforcing layer 950 . The sidewall reinforcing layer 950 may be disposed above the insertion layer 900 , specifically, the first cover part 920 and the second cover part 930 to further reinforce the sidewall part 200 .

In one embodiment, the sidewall reinforcement layer 950 may include a first reinforcement part 951 disposed on the first cover part 920 . The first reinforcement part 951 covers the upper part of the first cover part 920 and may be disposed such that one side of the first reinforcement part 951 completely covers one side of the first cover part 920 . In addition, the sidewall reinforcing layer 950 may include a second reinforcing part 952 disposed on the second cover part 930 . The second reinforcement part 952 covers the upper part of the second cover part 930 and may be disposed so that one side of the second reinforcement part 952 completely covers one side of the second cover part 930 . Accordingly, the tire 10 for an electric vehicle according to the present invention can secure a grounding area by maintaining the shape of the sidewall portion 200 .

As described above, the tire 10 for an electric vehicle according to the present invention includes the insertion layer 900 to increase the contact area between the tread and the ground, thereby improving riding and handling performance. This can improve the contact area without causing an increase in the width of the belt layer 500 in order to compensate for the disadvantages of the tire 10 for an electric vehicle being formed in a narrow-and-tall type shape.

As such, the present invention has been described with reference to the embodiments shown in the drawings, but this is only an example. Those skilled in the art can fully understand that various modifications and equivalent other embodiments are possible from the embodiments. Therefore, the true technical protection scope of the present invention should be determined based on the appended claims.

Specific technical details described in the embodiments are examples, and do not limit the technical scope of the embodiments. In order to briefly and clearly describe the description of the invention, descriptions of conventional general techniques and configurations may be omitted. In addition, the connection of lines or connection members between the components shown in the drawing is an example of functional connection and / or physical or circuit connection, which can be replaced in an actual device or additional various functional connections, physical connections, or circuit connections. In addition, if there is no specific reference such as "essential" or "important", it may not necessarily be a component necessary for the application of the present invention.

“Above” or similar designations described in the description and claims of the invention may refer to both singular and plural, unless otherwise specifically limited. In addition, when a range is described in an embodiment, it includes an invention in which individual values belonging to the range are applied (unless there is no description to the contrary), and each individual value constituting the range is described in the description of the invention. same. In addition, if there is no clear description or description of the order of steps constituting the method according to the embodiment, the steps may be performed in an appropriate order. Embodiments are not necessarily limited according to the order of description of the steps. The use of all examples or exemplary terms (eg, etc.) in the embodiments is simply to describe the embodiments in detail, and unless limited by the claims, the examples or exemplary terms limit the scope of the embodiments. It is not. In addition, those skilled in the art will appreciate that various modifications, combinations and changes may be made according to design conditions and factors within the scope of the appended claims or equivalents thereof.

100: tread part 200: sidewall part
300: bead part 400: body ply
500: belt layer 600: cap ply
700: inner liner 900: insertion layer

Claims (11)

a tread portion including an area in contact with the ground;
Sidewall portions extending from both sides of the tread portion;
a belt layer disposed under the tread portion;
a body ply disposed under the belt layer;
and an insertion layer disposed between the belt layer and the body ply and pressurizing the tire outward to increase a contact area between the tread and the ground. According to claim 1,
The sidewall unit includes a first sidewall on one side and a second sidewall on the other side,
The insertion layer is disposed to extend from a junction between the first sidewall and the tread portion to a junction between the second sidewall and the tread portion. According to claim 2,
The insertion layer is disposed such that one end covers an interface between the tread portion and the first sidewall, and the other end covers an interface between the tread portion and the second sidewall. According to claim 1,
The insertion layer is
a body portion having a first curvature toward the tread portion;
a first cover part extending along one of the sidewalls from one end of the body part and having a second curvature; and
A tire for an electric vehicle comprising: a second cover portion extending from the other end of the body portion along the other one of the sidewalls and having a third curvature. According to claim 4,
The second curvature is different from the third curvature, a tire for an electric vehicle. According to claim 4,
A tire for an electric vehicle, wherein the thickness of the body portion becomes thinner toward the outside from the center in the tire width direction. According to claim 1,
The modulus of the insertion layer is greater than the modulus of the sidewall portion, a tire for an electric vehicle. According to claim 7,
The modulus of the insertion layer is greater than 1 times and less than 1.5 times the modulus of the sidewall portion. According to claim 1,
A tire for an electric vehicle, wherein a width of the insertion layer in the tire width direction is greater than a width of the belt layer. According to claim 1,
The thickness of the insertion layer is thinner than the thickness of the belt layer, a tire for an electric vehicle. According to claim 4,
The tire for an electric vehicle further comprising a; sidewall reinforcing layer including a first reinforcing part disposed on the upper part of the first cover part and a second reinforcing part disposed on the upper part of the second cover part.

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