Low-rolling-resistance and low-noise new energy automobile tire tread

Abstract

The invention relates to the technical field of pneumatic tires, and discloses a low-rolling-resistance and low-noise new energy automobile tire. The tire tread is provided with a plurality of pitches, each pitch is internally provided with transverse main grooves and auxiliary grooves, and the main grooves and the auxiliary grooves are alternately arranged. The cross section of the main groove is funnel-shaped, the cross section of the upper part is inverted trapezoidal and is communicated with the outside, and the lower part of the funnel is a main groove thin groove; the section of the auxiliary groove is in an inverted funnel shape, the upper portion is an auxiliary groove thin groove and communicated with the outside, the section of the lower portion is trapezoidal, and the size design of the auxiliary groove is matched with that of the main groove. Through the design of the auxiliary grooves and the combination of the main grooves and the auxiliary grooves, the rolling resistance and noise of the tire can be effectively reduced, the weight of the tire is reduced, and the stability of the tread after saturation abrasion is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of pneumatic tires, and more particularly to a tread pattern groove of a new energy vehicle tire, which has better performance in rolling resistance and noise reduction. Background Art

[0002] In recent years, climate change has become the focus of world attention. To this end, countries have formulated strict laws and introduced relevant measures in terms of environmental protection and energy conservation. In order to meet people's requirements for environmental protection and energy conservation, electric vehicles, dual-fuel vehicles, solar vehicles and hydrogen vehicles have been developed, and strict control standards have been formulated for the emissions of fuel vehicles. In order to meet the needs of the development of the automotive industry, developed countries such as Europe and the United States have successively formulated and implemented new tire regulations and standards, such as the EU's REACH law, labeling law and the United States' SMARTWAY. For this reason, tire companies have developed and designed new products, especially new energy vehicle tires, using new technologies, new materials and new processes to produce high-performance tires. In order to meet the performance requirements of such vehicles for tires, the development, design and promotion of new energy vehicle tires will be the focus of new product development for tire companies in the future.

[0003] Compared with traditional tires, new energy vehicle tires have greater ground pressure, and the instantaneous torque provided by the electric motor is greater, which places higher requirements on the rolling resistance and low noise of the tires. The hysteresis loss related to rolling resistance is defined as the result of three parameters, namely volume, strain energy and tanδ. The rolling resistance decreases as these three values ​​decrease. Noise reduction is mainly achieved through the optimization of the tire pattern, including modifying the volume, shape and position of the transverse grooves and longitudinal grooves, as well as the design of special grooves and the optimization of the pitch. In the prior art, for non-new energy tire pattern grooves, the main groove cross-section mostly adopts a U-shaped design, and the secondary groove adopts a fine groove. For conventional new energy tire pattern grooves, in order to enhance the tread rigidity, the main groove cross-section mostly adopts a funnel-shaped design, with a large upper opening and a narrow lower part. At the same time, the fine grooves are eliminated and the pattern pitch length is reduced. Although the tread rigidity is enhanced, the tire still has problems of uneven stress distribution and uneven energy loss distribution, which leads to increased tire rolling resistance. The cancellation of fine grooves and the uneven distribution of grooves result in unsatisfactory noise performance of the tire. At the same time, conventional new energy tires still have problems such as large tube cavity resonance noise and tread impact noise due to the large volume of the ground contact grooves. Summary of the invention

[0004] The purpose of the present invention is to provide a new energy vehicle tire with low rolling resistance and low noise, so as to solve the problem of tread stress distribution and meet more extreme low rolling resistance and low noise performance requirements.

[0005] In order to achieve the above object, the present invention provides the following technical solutions: A low rolling resistance, low noise new energy vehicle tire, wherein the tread of the tire is provided with longitudinally oriented ribs, at least three longitudinally oriented grooves and a tire shoulder, wherein the ribs and / or the tire shoulder are provided with a plurality of pitches distributed along the circumferential direction, the pitch length is L1, and transverse main grooves and transverse secondary grooves are provided in each pitch, and the main grooves and the transverse secondary grooves are arranged alternately; The main groove has a funnel-shaped cross section, with an inverted trapezoidal cross section at the top, which is connected to the outside. The lower part of the funnel is a main groove fine groove. The circumferential width of the main groove opening is W1, and the depth is D. The upper depth of the main groove is D1, and the width of the main groove fine groove is not more than 1.5 mm. The cross section of the auxiliary groove is in the shape of an inverted funnel, the upper part is the auxiliary groove, which is connected to the outside, and the lower cross section is a trapezoid; the circumferential width of the auxiliary groove bottom is B1, the depth is H1, the depth of the auxiliary groove is H2, and the width is not more than 1.5mm.

[0006] Preferably, a transverse main groove and a transverse sub-groove are arranged in each pitch.

[0007] Preferably, the auxiliary grooves are arranged at equally divided positions between two circumferentially adjacent main grooves.

[0008] Preferably, 0.2D≤D1≤0.8D.

[0009] Preferably, 0.5D≤H1≤D, 0.2D≤H2≤D1.

[0010] Preferably, 1.5 mm ≤ B1 ≤ W1.

[0011] Beneficial effects of the present invention: 1) The design of the auxiliary groove hides a part of its volume inside the tread to form an internal cavity. The internal cavity is not directly grounded, which reduces the volume of the ground contact transverse groove. According to the noise reduction mechanism, it can reduce the tube cavity resonance noise and tread impact noise; at the same time, it increases the volume rate of the groove, reduces the volume of the rubber, reduces the weight of the tire, thereby reducing the hysteresis loss and reducing the rolling resistance of the tire.

[0012] 2) The combination of main grooves and auxiliary grooves makes the groove distribution more balanced, thereby making the stress distribution more balanced, reducing the strain and making the distribution of energy loss more uniform, thereby reducing hysteresis loss and reducing the rolling resistance of the tire; and making the tread stiffness more balanced, which can reduce the tread impact noise.

[0013] 3) The fine grooves in the main grooves and the secondary grooves can better connect and support the tread blocks, reduce the strain of the tread blocks, thereby reducing the hysteresis loss and reducing the rolling resistance of the tire.

[0014] 4) In the later period of tire use, the main grooves and secondary grooves are worn to the lower part. This design allows the tread saturation to remain stable and the performance of the tire can be basically maintained. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the tire tread structure of the present invention; Figure 2 is a schematic cross-sectional view of a tire tread of the present invention; Figure 3 This is a schematic diagram of the tread structure of a conventional new energy tire; Figure 4 It is a schematic cross-sectional view of the tread of a conventional new energy tire; Figure 5 This is a schematic diagram of the tread structure of a non-new energy tire; Figure 6 This is a schematic cross-sectional view of a non-new energy tire tread. DETAILED DESCRIPTION

[0016] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0017] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0018] Figure 1-3 The tread surface on the right side of the tire’s equatorial midplane (XX') is shown.

[0019] like Figure 1 , 2 As shown, a low rolling resistance, low noise new energy vehicle tire is provided with a transverse main groove 31 and a transverse secondary groove 32 in each pitch of the tire shoulder (3), the main groove 31 and the transverse secondary groove 32 are arranged alternately, and the secondary groove 32 is arranged at an equally divided position between two circumferentially adjacent main grooves 31.

[0020] The main groove 31 has a funnel-shaped cross section, the upper cross section is an inverted trapezoid, connected to the outside, and the lower part of the funnel is a main groove; the auxiliary groove 32 has an inverted funnel-shaped cross section, the upper part is an auxiliary groove, connected to the outside, and the lower cross section is a trapezoid.

[0021] The pitch length of the tire shoulder (3) is L1=30mm; the main groove 31 has a circumferential width of W1=4mm and a depth of D=6mm, the upper depth of the main groove 31 is D1=3mm, and the width of the narrow groove is 0.6mm; the secondary groove 32 has a circumferential width of B1=2.6mm and a depth of H1=6mm; the narrow groove has a depth of H2=3mm and a width of 0.6mm.

[0022] Comparative Example 1 like Figure 3 , 4 As shown, a conventional new energy tire tread has only one transverse first main groove 33 in each pitch of the tire shoulder (3). The cross section of the first main groove 33 is the same as the cross section of the main groove 31, but the specifications are different.

[0023] The pitch length L2 = 25mm; the circumferential width W2 = 4mm and the depth D = 6mm of the first main groove 33, the lower groove width B2 = 2mm and the depth D2 = 3mm. Among them, L2 ≈ 0.83 * L1, this design can reduce the excess rigidity and increase the number of pitches, thereby improving the tire's wet grip, traction and noise performance.

[0024] Comparative Example 2 like Figure 5 , 6 As shown, a non-new energy tire tread has only one transverse second main groove 34 and one transverse fine groove 35 in each pitch of the tire shoulder (3), the second main grooves 34 and the fine grooves 35 are arranged alternately, and the fine grooves 35 are arranged at equally divided positions between two circumferentially adjacent second main grooves 34. The cross-sections of the second main grooves 34 and the fine grooves 35 are both square.

[0025] The pitch length L3=30 mm; the second main groove 34 has a circumferential width W3=4 mm and a depth D=6 mm, and the fine groove 35 has a depth D3=6 mm and a width of 0.6 mm.

[0026] The specification of the slick tire used is 215 / 50R16. The structure and compound of the slick tire are the same and it is tested using current EU standards. Example Comparative Example 1 Comparative Example 2 Rolling resistance coefficient 5.5 5.7 6.2 Passing noise dB(A) 69.7 69.9 70.2

[0027] It can be obtained through actual measurement that the embodiments of the present invention have obvious improvements in rolling resistance and noise compared with non-new energy designs and conventional new energy designs. The rolling resistance coefficient is improved by 11.3% compared with the non-new energy design and by 3.5% compared with the conventional new energy design. The passing noise is improved by 0.5dB (A) compared with the non-new energy design and by 0.2dB (A) compared with the conventional new energy design.

[0028] The above is a description of the embodiments of the present invention. Through the above description of the disclosed embodiments, professionals and technicians in the field can implement or use the present invention. Various modifications to these embodiments will be apparent to professionals and technicians in the field. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown in this article, but will conform to the widest range consistent with the principles and novelties disclosed herein.

Claims

1. A low rolling resistance, low noise new energy vehicle tire, wherein the tire tread is provided with longitudinally oriented ribs (1), at least three longitudinally oriented grooves (2) and a tire shoulder (3), characterized in that: The rib (1) and / or the tire shoulder (3) are provided with a plurality of pitches distributed along the circumferential direction, the pitch length is L1, a transverse main groove (31) and a transverse auxiliary groove (32) are provided in each pitch, and the main groove (31) and the transverse auxiliary groove (32) are arranged alternately; The main groove (31) has a funnel-shaped cross section, the upper cross section is an inverted trapezoidal cross section, connected to the outside, and the lower part of the funnel is a main groove fine groove; the main groove (31) has an opening circumferential width W1 and a depth D, the upper depth of the main groove (31) is D1, and the width of the main groove fine groove is not greater than 1.5 mm; The auxiliary groove (32) has an inverted funnel-shaped cross section, the upper portion is an auxiliary groove fine groove connected to the outside, and the lower portion has a trapezoidal cross section; the auxiliary groove (32) has a circumferential width B1 and a depth H1 at the bottom, and a depth H2 and a width not greater than 1.5 mm.

2. A low rolling resistance, low noise new energy vehicle tire according to claim 1, characterized in that: A transverse main groove (31) and a transverse secondary groove (32) are arranged in each pitch.

3. The low rolling resistance and low noise new energy vehicle tire according to claim 1, characterized in that: The auxiliary grooves (32) are arranged at equally spaced positions between two circumferentially adjacent main grooves (31).

4. The low rolling resistance and low noise new energy vehicle tire according to claim 1, characterized in that: 0.2D≤D1≤0.8D.

5. The low rolling resistance and low noise new energy vehicle tire according to claim 1, characterized in that: 0.5D≤H1≤D, 0.2D≤H2≤D1.

6. The low rolling resistance and low noise new energy vehicle tire according to claim 1, characterized in that: 1.5mm≤B1≤W1.

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