Shoulder-eccentric-wear-resistant pneumatic tire with wet-skid-resistant and stone-clamping-resistant functions

Abstract

The invention discloses a pneumatic tire capable of preventing shoulder eccentric wear with wet skid resistance and stone clamping resistance, which comprises a tread, the tread is provided with a plurality of circumferential grooves, the circumferential grooves comprise shoulder circumferential grooves positioned on the shoulder of the tread, the shoulder circumferential grooves are provided with three sections of grooves and a large groove, and the large groove is provided with three sections of grooves. Wherein the three-section groove comprises a small notch, a thin groove and a water storage groove which are sequentially arranged from the tread to the bottom of the circumferential groove of the shoulder part in the positive radial direction of the tire; wherein the narrow groove comprises wall surfaces parallel to each other, and the wall surfaces parallel to each other are contacted and supported by each other due to elastic deformation when the tire is grounded; the large grooves are periodically distributed in the circumferential direction of the shoulder circumferential groove at intervals, the small notches and the thin grooves in the corresponding positions are widened, and a drainage path communicated with the water storage groove is formed. Through the composite design of the three sections of grooves in the circumferential groove of the shoulder part and the periodically distributed large grooves, the three performances of eccentric wear resistance, wet skid resistance and stone clamping resistance are remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of tire technology, and in particular to a pneumatic tire that combines anti-slip, anti-stone trapping, and anti-shoulder wear functions. Background Technology

[0002] Typical tires used in buses or trucks have complex interrelationships among their many key performance indicators, such as rolling resistance, wet grip (anti-skid), wear resistance, stone trapping resistance, and anti-uniform wear resistance. Balancing these performance characteristics is a key challenge in tire design.

[0003] Currently, the use of wider circumferential grooves and high-density sipes to improve wet performance, while beneficial for wet grip, significantly increases rolling resistance and fuel consumption. Although these designs enhance water drainage, they reduce tread rigidity, accelerate tread wear, and can even cause uneven wear due to uneven tread rigidity distribution. Uneven wear leads to uneven tire contact pressure distribution, increasing rolling resistance; it also causes uneven tread block height, generating periodic vibration noise at high speeds; most importantly, uneven tire wear reduces lateral grip during cornering, increasing the risk of vehicle skidding and causing safety issues.

[0004] Conversely, while narrower circumferential grooves can enhance the rigidity of the pattern and achieve the goal of preventing uneven wear, they will significantly reduce the volume of the grooves, sacrifice some wetland performance, and make the circumferential grooves more prone to trapping stones.

[0005] It is evident that there is an irreconcilable contradiction between tire wear performance (wear mileage, anti-uniform wear), wet performance, and anti-stone trapping performance.

[0006] Chinese invention patent CN119911038A discloses a low rolling resistance pneumatic tire. Its main inventive concept lies in improving the central circumferential grooves of the tire, employing a three-section radial structure consisting of a slit groove, fine grooves, and a water reservoir. By making the width of the central fine groove smaller than the widths of the slit groove and the water reservoir, a "dumbbell-shaped" cross-section is formed. This design aims to enhance the rigidity of the tread blocks and reduce rolling resistance through the wall contact of the fine grooves upon contact with the ground, while simultaneously utilizing the water reservoir to ensure drainage performance. However, this technical solution has the following shortcomings in addressing the issue of uneven wear on the shoulder: 1. Inability to solve the core wear problem: The solution in CN119911038A mainly optimizes the circumferential grooves in the central area. However, for commercial vehicle tires such as trucks and buses, the shoulder tread blocks bear the greatest stress and are most prone to abnormal uneven wear due to the lateral forces during steering. Therefore, this existing technology does not provide a specific and effective solution for the shoulder grooves, which are most prone to uneven wear, and its technical effects cannot be directly applied to solving the problem of uneven shoulder wear.

[0007] 2. Limited performance balance: The three-section groove design is uniform or gradually varied along its entire circumferential length, lacking regionalized and differentiated design for different functions. While pursuing drainage and stone trapping prevention, it struggles to continuously and effectively provide sufficient support rigidity to resist lateral forces that cause uneven wear during the critical tire contact phase, especially in the shoulder area where this lack of rigidity is more pronounced.

[0008] In summary, considering the shoulder area, which is most prone to uneven wear, a groove structure for an inflatable tire is designed to synergistically improve anti-uneven wear performance, anti-slip performance, and anti-stone trapping performance. Summary of the Invention

[0009] To address the aforementioned technical problems, this invention provides a pneumatic tire with anti-slip and anti-stone-clamping functions, which also prevents shoulder wear. The tire includes a tread with several circumferential grooves, including a shoulder circumferential groove located at the shoulder of the tread. This shoulder circumferential groove has three sections and a large recess, wherein: The three-section groove includes a small cut, a fine groove, and a water reservoir arranged sequentially along the radial direction of the tire from the tread to the bottom of the shoulder circumferential groove; wherein, the fine groove includes mutually parallel walls, and when the tire touches the ground, the mutually parallel walls contact and support each other due to elastic deformation; The large grooves are periodically distributed along the circumferential direction of the shoulder groove, and the corresponding small cuts and fine grooves are widened to form a drainage path that communicates with the water storage tank.

[0010] Furthermore, the axial widths W1, W2, and W3 of the small incision, fine groove, and water storage tank satisfy the following relationship: 1.5W2≤W1≤16mm; 0.5mm≤W2≤3.2mm; 1.4W2≤W3≤13.5W2.

[0011] Furthermore, the large groove widens the size of the small cut to form a large cut; the large groove widens the size of the narrow groove to form a wide groove; then the axial widths W11 and W22 of the large cut and the wide groove satisfy the following relationship: 1.5W1≤W11≤3.5W1; 3W2≤W22≤20mm.

[0012] Furthermore, the depth h1 of the small incision, the depth h2 of the fine groove, the depth h3 of the water reservoir, and the tread depth H satisfy the following relationship: h1 + h2 + h3 = H; 0.07H≤h1≤0.42H; 0.16H≤h2≤0.51H; 0.24H≤h3≤0.61H.

[0013] Furthermore, the depths h11 and h22 of the large incision and wide groove satisfy the following relationship: h11=h1; h22>h2.

[0014] Furthermore, the small cut forms two opposing walls on the tread pattern, and the included angle α formed by the opposing walls in the tire axial direction satisfies the relationship 23°≤α≤135°.

[0015] Furthermore, the water storage tank forms two opposing walls on the radial inner side of the fine groove, and the included angle δ formed by the opposing walls in the tire axial direction satisfies the relationship 25°≤δ≤130°.

[0016] Furthermore, the cross-sectional areas S1 and S2 of the shoulder circumferential groove at the three-section groove and at the widest point of the large groove satisfy the relationship 1.2S1≤S2≤3.5S1.

[0017] Furthermore, the repeating length L of the large groove along the tire circumference satisfies the relationship L=N*PL with respect to the tread pitch, where 0.4≤N≤5.

[0018] Furthermore, the bottom of the large groove is provided with an upwardly protruding stone-throwing device, and the axial width W4 and radial height h4 of the stone-throwing device satisfy the following relationship: 0.5mm≤W4≤0.5W3; 0.8mm≤h4≤0.8h3.

[0019] Compared with the prior art, the embodiments of the present invention have the following beneficial effects: This invention employs a composite design of three grooves within the shoulder circumferential groove and periodically distributed large grooves. This design allows the fine groove walls to contact the tire when it touches the ground, greatly enhancing the rigidity of the tread blocks and effectively resisting lateral forces to prevent uneven wear. Simultaneously, the large grooves and water storage tanks form an efficient drainage path to ensure wet grip throughout the entire cycle. Furthermore, by utilizing changes in groove morphology and the bottom stone ejector to actively remove stones, this invention ultimately achieves a significant improvement in three major performance aspects in the shoulder area: anti-uneven wear, anti-slip, and anti-stone trapping. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a top view of a tire tread pattern with circumferential grooves disclosed in an embodiment of the present invention; Figure 2(a) is an enlarged top view of the specially designed shoulder circumferential groove disclosed in an embodiment of the present invention; Figure 2(b) is an enlarged perspective view of the specially designed shoulder circumferential groove disclosed in an embodiment of the present invention.

[0022] Figure 3(a) is a cross-section of the plane UU in Figure 2 disclosed in the embodiment of the present invention, showing the positions of the three slots; Figure 3(b) is an enlarged view of Figure 3(a) disclosed in the embodiment of the present invention; Figure 3(c) is a cross-sectional comparison of the cross-sectional plane UU in Figure 2 disclosed in the embodiment of the present invention, showing the structure without the water storage tank; Figure 3(d) is a cross-section of the cross-sectional plane VV in Figure 2 disclosed in the embodiment of the present invention, showing the position of the change process in the middle of the large groove; Figure 3(e) is an enlarged view of Figure 3(c) disclosed in the embodiment of the present invention; Figure 3(f) is a cross-section of the plane WW in Figure 2 disclosed in the embodiment of the present invention, showing the position of the widest part of the large groove; Figure 3(g) is an enlarged view of Figure 3(e) disclosed in the embodiment of the present invention; Figure 4(a) shows the cross-sectional area of ​​the cross-sectional plane UU in Figure 2 disclosed in the embodiment of the present invention, illustrating the positions of the three slots; Figure 4(b) shows the cross-sectional area of ​​the cross-sectional plane WW in Figure 2 as disclosed in the embodiment of the present invention, indicating the position of the widest part of the large groove; Figure 5 This is a cross-sectional view of the stone-throwing device along the WW direction in Figure 2, as disclosed in an embodiment of the present invention; Figure 6(a) is a top view of a tire tread pattern with conventional circumferential grooves disclosed in an embodiment of the present invention; Figure 6(b) is a top view of a tire tread pattern with only three grooves in the shoulder circumferential groove disclosed in an embodiment of the present invention; Figure 7 These are five alternative implementations of the small incision disclosed in the embodiments of the present invention; Figure 8These are four alternative implementations of the water storage tank disclosed in the embodiments of the present invention; Figure 9 These are three alternative implementations of the top view of the circumferential trench disclosed in the embodiments of the present invention; Figure 10 These are four alternative implementation schemes for the large groove bottom boss disclosed in the embodiments of the present invention.

[0023] In the picture: 1. Inner shoulder block; 2. Inner central block; 3. Central block; 4. Outer central block; 5. Outer shoulder block; 6. First shoulder circumferential groove; 7. First central circumferential groove; 8. Second central circumferential groove; 9. Second shoulder circumferential groove; 61. Small incision; 611. Large incision; 62. Fine groove; 622. Wide groove; 63. Water storage tank; 64. Stone projectile; 101. Side wall of small incision; 102. Side wall of fine groove; 103. Side wall of water storage tank; 104. Bottom of water storage tank; 201. Side wall of large incision; 202. Side wall of wide groove. Detailed Implementation

[0024] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] The present invention aims to provide a pneumatic tire that combines anti-slip, anti-stone trapping and anti-shoulder wear functions. Through the special design of the tire circumferential grooves and the reasonable configuration of design parameters, the tire is ensured to have excellent anti-shoulder wear performance, anti-stone trapping performance and wet performance.

[0026] The pneumatic tire includes a tread with several circumferential grooves extending along the tire's circumference and lateral sipes extending axially outward. The circumferential grooves, from the inner to the outer side of the tire, sequentially include a first shoulder circumferential groove, a first central circumferential groove, a second central circumferential groove, and a second shoulder circumferential groove, dividing the tread into five main circumferential blocks. To enhance the tire's resistance to shoulder wear, wet-weather performance, and stone-trapping resistance, the first and second shoulder circumferential grooves are the primary design features. Specifically, the shoulder circumferential groove is formed by a specially designed three-segment groove as its basic groove shape. Large grooves are then periodically spaced along the tire's circumferential direction on the shoulder circumferential groove. The combination of the three-segment groove and the large grooves ultimately forms the unique shoulder circumferential groove shape of this technical solution.

[0027] The three-section groove system comprises a small slit, a fine groove, and a water reservoir, arranged sequentially along the radial direction of the tire, from the tread to the bottom of the shoulder circumferential groove. The small slit is located between the tread surface and the fine groove, defined by a pair of sidewalls positioned opposite each other circumferentially. The fine groove is formed radially from the small slit, defined by a pair of substantially parallel groove walls extending circumferentially. This allows the fine grooves to contact and support each other upon contact with the tire rubber due to elastic deformation, thereby increasing the rigidity of the tire shoulder, resisting lateral forces during cornering, and preventing uneven shoulder wear. The water reservoir is formed radially from the fine groove and extends circumferentially. The fine groove connects the water reservoir to the small slit, creating internal connectivity within the shoulder circumferential groove.

[0028] The large grooves on the shoulder are periodically spaced in the circumferential direction, and the corresponding small cuts and fine grooves are widened to form a drainage path connected to the water storage tank. Specifically, the large grooves enlarge the size of the small cuts to form large cuts on the tire surface; the large grooves enlarge the size of the fine grooves to form wide grooves, which are connected to the water storage tank. This allows water in the cut spaces at the points where the fine grooves are closed due to grounding to quickly enter the water storage tank space through the large grooves, and can be discharged to the outside of the tire through the shoulder circumferential grooves in the area above the ground. This ensures the drainage of the shoulder circumferential grooves and guarantees wet grip performance.

[0029] In a further design, the axial widths of the small incision, large incision, fine groove, wide groove, and water storage tank are denoted as W1, W11, W2, W22, and W3, respectively, and they satisfy the following relationship: 1.5W2≤W1≤16mm, and preferably 2.8mm≤W1≤10.2mm; 1.5W1≤W11≤3.5W1, and preferably 1.8W1≤W11≤2.7W1; 0.5mm≤W2≤3.2mm, and preferably 1.0mm≤W2≤2.5mm; 3W2≤W22≤20mm, and preferably 5mm≤W22≤12mm; 1.4W2≤W3≤13.5W2, and preferably 4.8W2≤W3≤8.2W2.

[0030] In a further embodiment, the transition arc connecting the large cut and the small cut is denoted as Re; the transition arc connecting the wide groove and the narrow groove is denoted as Rc. The two satisfy the relationship: 0.5mm≤Rc≤Re, and preferably 1.5mm≤Rc≤Re.

[0031] In a further embodiment, the small cut forms two opposing walls on the tread pattern, and the opposing walls form an included angle α in the tire axial direction. The intersection of the opposing walls occurs inside the tread, and α satisfies the relationship: 23°≤α≤135°, and preferably 40.5≤α≤86°.

[0032] In a further embodiment, the water reservoir forms two opposing walls on the radially inner side of the fine groove. These opposing walls form a non-zero angle δ along the tire axial direction. The intersection of these opposing walls occurs inside the tread, and δ satisfies the relationship: 25°≤δ≤130°. These opposing walls are connected to the bottom of the water reservoir by two arc segments, the radii Ra of which satisfy the relationship: 0.5mm≤Ra≤5.5mm, and preferably 1.1mm≤Ra≤2.6mm.

[0033] In a further design, the depths of the small slit, large slit, fine groove, wide groove, and water reservoir along the radial direction of the tire are denoted as h1, h11, h2, h22, and h3, respectively, and the tread has a tread depth H. These depths satisfy the following relationship: h1=h11; h1(h11) + h2 + h3 = H; h2 < h22; h3 > h33; 0.07H≤h1(h11)≤0.42H, and preferably 0.14H≤h1(h11)≤0.36H; 0.16H≤h2≤0.51H, and preferably 0.23H≤h2≤0.43H; 0.24H≤h3≤0.61H.

[0034] In a further embodiment, the shoulder circumferential groove has a certain cross-sectional area along the tire axis. The cross-sectional areas S1 and S2 of the shoulder circumferential groove at the three-section groove and the widest part of the large groove satisfy the relationship: 1.2S1≤S2≤3.5S1.

[0035] In a further design, the repeating length L of the large groove along the tire circumference satisfies the relationship PL of the tread pitch: L=N*PL, where 0.4≤N≤5.

[0036] In a further embodiment, a stone-throwing device is provided at the bottom of the groove, and the axial width W4 and radial height h4 of the stone-throwing device satisfy the following relationship: 0.5mm≤W4≤0.5W3; 0.8mm≤h4≤0.8h3.

[0037] In a specific example, such as Figure 1As shown in Figure 2, pneumatic tires that also have anti-skid and anti-stone-clamping functions and prevent shoulder wear are mainly used in buses or trucks. They include a tread, four circumferential grooves extending along the tire's circumferential X direction, and lateral sipes extending outward along the tire's axial Y direction. The circumferential grooves divide the tread into multiple strip-shaped tread blocks. These blocks, from the inside to the outside of the tire, include an inner shoulder block 1, an inner central block 2, a central block 3, an outer central block 4, and an outer shoulder block 5. The circumferential grooves, from the inside to the outside of the tire, sequentially include a first shoulder circumferential groove 6, a first central circumferential groove 7, a second central circumferential groove 8, and a second shoulder circumferential groove 9.

[0038] As shown in Figures 3(a) and 3(b), the first or second shoulder circumferential groove adopts a special three-segment groove design within a certain length L3 along the tire circumference. Small cutouts 61 are provided in the first or second shoulder circumferential groove, defined by a pair of walls 101. The sidewalls 101 of the small cutouts are substantially opposite to each other and extend along the circumferential direction of the first or second shoulder circumferential groove. These small cutouts can increase the tire's grip edge, increase the volume of the shoulder circumferential groove, and improve the tire's wet-weather performance; they can also expel stones, improving anti-stone trapping performance.

[0039] Fine grooves 62 are provided in the positive radial direction of the small incision 61. The fine grooves 62 are defined by a pair of walls, the side walls of which are substantially parallel to each other and extend in the circumferential direction along the first shoulder circumferential groove or the second shoulder circumferential groove. The fine grooves can contact and support each other due to the elastic deformation of the tire rubber when the tire contacts the ground, thereby improving the rigidity of the tire shoulder, resisting lateral forces during cornering, and preventing uneven wear of the shoulder.

[0040] Optionally, the cross-sectional shape of the small cut 61 in the radial direction of the tire is not limited to the triangle shown in Figure 3, and can also be replaced with... Figure 7 The polygons shown in (a)-(e) are shown in the middle.

[0041] A water reservoir 63 is provided in the positive radial direction of the fine groove 62, extending radially inward into the tread. This water reservoir 63 is connected to the small cutout 61 through the fine groove 62. The water reservoir 63 increases the volume of the shoulder circumferential groove, improving the tire's wet performance. Simultaneously, it disperses stress at the groove bottom, preventing stress concentration. As shown in Figure 3(c), without the water reservoir 63, stress concentration may occur at the bottom of the shoulder circumferential groove, causing groove bottom tearing and affecting tire lifespan.

[0042] Optionally, the shape of the cross-section of the water reservoir 63 in the radial direction of the tire is not limited to that shown in Figure 3, and can also be replaced with... Figure 8 The shape of (a)-(d).

[0043] As shown in Figure 3(a), the axial widths W1, W2, and W3 of the small cut 61, fine groove 62, and water reservoir 63 are as follows: 1.5W2≤W1≤16mm, and preferably 2.8mm≤W1≤10.2mm; 0.5mm≤W2≤3.2mm, and preferably 1.0mm≤W2≤2.5mm; 1.4W2≤W3≤13.5W2, and preferably 4.8W2≤W3≤8.2W2. With the depths of the small cut 61, fine groove 62, and water reservoir 63 remaining constant, when W1 < 1.5W2, W1 is too small, resulting in insufficient contact edge for traction and braking, and affecting wet performance and anti-stone trapping performance to some extent. When W1 is too large, the tread rigidity of the crown decreases, causing the tire to be prone to large bending deformation during driving or steering, leading to uneven tire wear.

[0044] The fine groove 62 is defined by a pair of basically parallel walls. When the distance W2 between the side walls 102 of the opposite fine groove is greater than 3.2 mm, W2 is too large. The tread block may not be able to make contact with itself during the tire rolling contact process. At this time, the reinforcement effect of the fine groove on the tread block is insufficient, resulting in insufficient overall rigidity of the shoulder tread block, and it cannot play a practical role in preventing shoulder wear.

[0045] When the tire axial width W3 > 13.5W2, the tire is difficult to demold during the tire manufacturing process, and the tread blocks may tear. When W3 < 1.4W2, the water storage volume of the water tank is limited, which is detrimental to the tire's wet performance.

[0046] Small cuts 61 form a pair of opposing sidewalls on the tread pattern, the opposing sidewalls forming an included angle α, the intersection of the sidewalls 101 occurring inside the tread, wherein α is between 23° and 135°, and preferably 40.5 ≤ α ≤ 86°, which can effectively increase the edge pressure on the tread.

[0047] The water storage tank 63 forms a pair of opposing sidewalls 103 between adjacent tread blocks. The sidewall 101 of the small cut is connected to the bottom surface 104 of the water storage tank by an arc. The radius Ra of the arc is between 0.5mm and 5.5mm, and preferably 1.1mm≤Ra≤2.6mm. When Ra>5.5mm, the volume of the water storage tank is reduced, and the tire's water storage and drainage capacity on wet roads decreases, impairing the tire's wet performance. When the tire wears to a certain extent, it cannot guarantee sufficient wet traction. When Ra<0.5mm, stress concentration is likely to occur at the arc connecting the opposing sidewalls 103 and the bottom surface 104 of the water storage tank during driving, affecting the tire's service life.

[0048] The water reservoir 63 forms a pair of opposing sidewalls between adjacent tread blocks. The opposing sidewalls 103 of the water reservoir form a non-zero included angle δ in the tire axial direction. The intersection of the opposing walls occurs inside the tread, where 25°≤δ≤130°. When δ>130°, demolding is difficult during tire manufacturing, which can easily cause tearing of the tread blocks.

[0049] As shown in Figure 3(a), the tread has a tread depth H, and the depths h1, h2, and h3 of the small cut 61, fine groove 62, and water reservoir 63 along the radial direction of the tire. The relationships between H and h1, h2, and h3 are as follows: h1 + h2 + h3 = H, 0.07H ≤ h1 ≤ 0.42H, and preferably 0.14H ≤ h1 ≤ 0.36H; 0.16H ≤ h2 ≤ 0.51H, and preferably 0.23H ≤ h2 ≤ 0.43H; 0.24H ≤ h3 ≤ 0.61H.

[0050] With the widths of the slit 71, the fine groove 72, and the water reservoir 73 remaining constant, when h2 < 0.16H, h2 is too small, weakening the connection and reinforcement of the small slit 61 and the water reservoir 63. Simultaneously, it reduces the contact area of ​​the sidewalls 102 of the fine grooves during tire rolling, preventing effective mutual support between adjacent tread blocks and failing to effectively enhance the rigidity of the shoulder tread, thus failing to prevent uneven wear of the shoulder tread. When h2 > 0.55H, the small slit 61 and the water reservoir 63 are too small, reducing the overall volume of the circumferential grooves and affecting the tire's wet performance.

[0051] Figures 3(d)-3(e) show the cross-section of plane VV in Figure 2. The first shoulder circumferential groove or the second shoulder circumferential groove adopts a special internal groove structure design within a certain length L1 (i.e., the position of the large groove). The large groove widens the width of the small cut 61 and the fine groove 62, increasing the volume of the first shoulder circumferential groove 6 or the second shoulder circumferential groove 9. This allows water in the cut space at the position of the fine groove 62 that is closed due to grounding to quickly enter the water storage tank 63 space through the large groove, and can be discharged to the outside of the tire through the shoulder circumferential groove in the off-ground area. This ensures the drainage of the shoulder circumferential groove and guarantees wet grip performance.

[0052] The large groove includes a large cut 611 formed in the first shoulder circumferential groove 6 or the second shoulder circumferential groove 9, the large cut 611 being defined by a pair of walls, the side walls 201 of the large cut being substantially opposite to each other.

[0053] A wide groove 622 is formed in the positive radial direction of the large cut 611. The wide groove 622 is defined by a pair of walls, and the side walls 202 of the wide groove are substantially opposite to each other. The wide groove 622 connects the large cut 611 and the water reservoir 63, and the side walls 202 of the wide groove maintain a certain gap width without closing when the tire is in contact with the ground.

[0054] As shown in Figure 2, the lengths L1 and L2 of the large cut 611 and the wide groove 622 along the tire circumferential direction have the following relationship: L2≤L1, and preferably 2L2≤L1≤3L2. When L2>L1, the wide groove is too large, which will affect the rigidity of the tire and thus affect the tire's service life.

[0055] As shown in Figure 2, the widths W11, W22, and W2 of the large cut 611, wide groove 622, and narrow groove 62 along the tire axial direction have the following relationship: W11 ≥ 1.5W22, W22 ≥ 1.5W2, and preferably 2W22 ≤ W11 ≤ 3W22, 4W2 ≤ W22 ≤ 7W2. When W11 < 1.5W22, the volume of the large cut 611 is small and cannot substantially affect the tire's drainage performance. When W22 < 1.5W2, the width of the wide groove 622 is small, and it may self-contact like the narrow groove 62 when the tire contacts the ground, failing to form a gap passage between the large cut 611 and the water reservoir 63, which is detrimental to the tire's drainage performance. Even without self-contact, the small width of the wide groove reduces its volume, thus affecting the tire's drainage performance.

[0056] As shown in Figure 3(d), the tread has a tread depth H, a large cut 611, a wide groove 622, and a water reservoir 63, and residual depths h11, h22, and h33 along the radial direction of the tire. The relationships between H and h1, h11, h2, h22, h3, and h33 are as follows: h1 = h11, h1(h11) + h2 + h3 = h1(h11) + h22 + h33 = H, h2 < h22, h3 > h33, 0.07H ≤ h1(h11) ≤ 0.42H, and preferably 0.14H ≤ h1(h11) ≤ 0.36H; 0.16H ≤ h2 ≤ 0.51H, and preferably 0.23H ≤ h2 ≤ 0.43H; 0.24H ≤ h3 ≤ 0.61H.

[0057] The enlarged top view of the shoulder circumferential groove is not limited to that shown in Figure 2(a), and can also be replaced with... Figure 9 The shapes shown in (a)-(c) are shown in the middle.

[0058] As shown in Figure 2, the transition arc connecting the small cut 61 and the large cut 611 is denoted as Re, and the transition arc connecting the fine groove 62 and the wide groove 622 is denoted as Rc. The relationship between the two is 0.5mm≤Rc≤Re, and preferably 2.0mm≤Rc≤Re. When Rc≤Re<0.5mm, stress concentration is likely to occur in the transition area, affecting the tire's lifespan.

[0059] As shown in Figure 4, the cross-sectional area of ​​the shoulder circumferential groove along the tire axial direction changes at the three-segment groove position and the large groove position. Figure 4(a) shows the cross-sectional area of ​​the plane UU in Figure 2 (three-segment groove position), and the cross-sectional area of ​​the shoulder circumferential groove at the ordinary three-segment groove UU position is denoted as S1; Figure 4(b) shows the cross-sectional area of ​​the plane WW in Figure 2 (the widest limit position of the large groove), and the cross-sectional area of ​​the shoulder circumferential groove at the WW position is denoted as S2; the relationship between S1 and S2 is: 1.5S1≤S2≤5S1, and preferably 2S1≤S2≤3.5S1. When S2<1.5S1, the volume of the large groove is small, and its contribution to the tire's water drainage performance is limited; when S3>5S1, the volume of the large groove is too large, which will affect the tire's rigidity, be detrimental to the tire's wear performance, and may lead to uneven wear near the large groove.

[0060] As shown in Figure 2, the repeating length L of the large grooves along the tire circumference satisfies the relationship L=N*PL with respect to the tread pitch: L=N*PL, where 0.5≤N≤4, and preferably 1.0≤N≤2.2. When N<0.5, the large grooves are too densely distributed, which reduces tire rigidity and is detrimental to wear performance. When N>4, the number of large grooves is insufficient, and when the tire contacts the ground, water cannot enter the water storage tank 63 through enough wide grooves 622, which is detrimental to the tire's wet performance and may cause safety issues.

[0061] To enhance the tire's ability to prevent stone trapping, such as Figure 5 As shown, a stone-spraying device 64 is installed at the bottom of the large groove in the tire. The width W4 of the stone-spraying device 64 along the tire axial direction satisfies the relationship: 1mm ≤ W4 ≤ 0.4W3; the depth h4 of the stone-spraying device 64 along the tire radial direction satisfies the relationship: 1mm ≤ h4 ≤ 0.7h3. When the width W4 of the stone-spraying device 64 is less than 1mm and the depth h4 is less than 1mm, the stone-spraying device 64 will not achieve the function of preventing stone trapping in the later stage of tire wear. When the width W4 of the stone-spraying device 64 is greater than 0.4W3 or the depth h4 is greater than 0.7h3, the stone-spraying device 64 significantly reduces the water storage volume of the water storage tank 63, thereby reducing the tire's wet performance. The top view of the stone-throwing device is not limited to Figure 1 The circle shown can also be replaced with Figure 10 The shapes shown in (a)-(d) are shown in the middle.

[0062] The shoulder circumferential groove of this technical solution adopts a special three-section groove structure design consisting of a small incision 61, a fine groove 62 and a water storage tank 63, and large grooves are periodically set along the circumferential direction of the tire. The parameters such as the width, depth and periodic spacing of the three-section groove and the large groove are reasonably configured, and the width and depth of the stone ejector 64 at the bottom of the large groove are reasonably designed to ensure that the tire can prevent shoulder wear and has excellent wet performance and anti-stone trapping performance.

[0063] We conducted experimental and simulation studies on the above design schemes, and the design schemes and research results are shown in Tables 1 and 2. The rolling resistance index was obtained through indoor rolling resistance testing, while the wet grip index and anti-stone trapping index were obtained through FEA simulation.

[0064] Table 1

[0065] Table 2

[0066] It should be noted that the higher the above index, the better the anti-abrasion performance; the greater the wet grip, the better the wet performance; and the stronger the anti-stone trapping ability, the better the anti-stone trapping performance.

[0067] Table 1 shows that, compared with conventional shoulder circumferential grooves, the circumferential grooves of this invention are significantly more beneficial for anti-uniform wear and anti-stone trapping performance. The width W2 of the cut 62 affects the tire's anti-uniform wear, wet grip, and anti-stone trapping performance. A smaller W3 width results in some loss of wet grip but is beneficial for anti-uniform wear and anti-stone trapping performance. A narrower groove width W22 results in a smaller cross-sectional area S2, which is not conducive to water entering the water storage tank at the bottom of the groove from the tread, resulting in some loss of wet grip but is beneficial for anti-uniform wear and anti-stone trapping performance. A longer groove length L2 results in some loss of anti-uniform wear and anti-stone trapping performance but is beneficial for wet grip. A larger repeat cycle of the large groove reduces the number of large grooves on the entire tread, which is beneficial for anti-uniform wear and anti-stone trapping performance but has a certain negative impact on wet grip.

[0068] Table 2 shows that the depth h2 of the fine groove affects the tire's anti-wear performance, wet grip performance, and stone trapping performance. The deeper h2 is, the better the anti-wear performance and stone trapping performance, but the wet grip performance will be reduced to some extent. The deeper the wide groove h22 is, the more the anti-wear performance and stone trapping performance will be reduced to some extent, but the wet grip performance will be improved.

[0069] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A pneumatic tire with anti-wet-skid and anti-stone-trapping functions and anti-shoulder-abrasion, comprising a tread, wherein the tread is provided with a plurality of circumferential grooves, and the circumferential grooves comprise a shoulder circumferential groove located at a shoulder of the tread, characterized in that, The shoulder circumferential groove has three-section grooves and large grooves, wherein: The three-section grooves include, in sequence from the tread to the bottom of the shoulder circumferential groove along the tire radial direction, a small notch, a fine groove and a water storage groove; wherein the fine groove includes mutually parallel wall surfaces that are in contact with each other for support due to elastic deformation when the tire is in contact with the ground; The large grooves are periodically and spacedly distributed along the circumferential direction of the shoulder circumferential groove, and widen the small notch and the fine groove at the corresponding positions to form a drainage path in communication with the water storage groove.

2. The tire according to claim 1, wherein The axial widths W1, W2 and W3 of the small notch, the fine groove and the water storage groove satisfy the following relationships: 1.5W2≤W1≤16mm; 0.5mm≤W2≤3.2mm; 1.4W2≤W3≤13.5W2.

3. The tire according to claim 2, wherein the shoulder portion of the tire is formed by a shoulder portion of the tread band and a shoulder portion of the under tread band. The large groove widens the size of the small notch to form a large notch; the large groove widens the size of the fine groove to form a wide groove; the axial widths W11 and W22 of the large notch and the wide groove satisfy the following relationships: 1.5W1≤W11≤3.5W1; 3W2≤W22≤20mm.

4. The tire according to claim 3, wherein The depths h1, h2 and h3 of the small notch, the fine groove and the water storage groove, and the tread depth H satisfy the following relationships: h1+h2+h3=H; 0.07H≤h1≤0.42H; 0.16H≤h2≤0.51H; 0.24H≤h3≤0.61H.

5. The tire according to claim 4, wherein The depths h11 and h22 of the large notch and the wide groove satisfy the following relationships: h11=h1; h22>h2.

6. The tire according to claim 1, wherein The two opposite wall surfaces formed by the small notch on the tread pattern satisfy the relationship 23°≤α≤135° in the tire axial direction.

7. The tire according to claim 1, wherein The two opposite wall surfaces formed by the water storage groove on the inside of the fine groove in the radial direction satisfy the relationship 25°≤δ≤130° in the tire axial direction.

8. The tire according to claim 1, wherein The cross-sectional areas S1 and S2 of the shoulder circumferential groove at the three-section groove and the widest part of the large groove satisfy the relationship 1.2S1≤S2≤3.5S1.

9. The tire according to claim 1, wherein The repeating length L of the large groove along the tire circumferential direction and the pitch PL satisfy the relationship L=N*PL, wherein 0.4≤N≤5.

10. The tire according to any one of claims 1 to 9, wherein The bottom of the large groove is provided with an upwardly protruding stone ejector, and the axial width W4 and the radial height h4 of the stone ejector satisfy the relationship: 0.5mm≤W4≤0.5W3; 0.8mm≤h4≤0.8h3.

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