A cap strip winding method and run-flat tire

Abstract

The present application discloses a cap band winding method and a run-flat tire. The cap band winding method forms three layers of first shoulders, three layers of second shoulders, and two layers of crowns after winding, which can improve the rigidity of the shoulders while ensuring the overall rigidity of the crown. The present application also provides a run-flat tire, the cap band layer includes three layers of first shoulders and second shoulders and two layers of crowns, and the reinforced cap band can enhance the tightening and binding effect of the cap band on the belt layer and other materials at high speeds, thereby improving high-speed performance. The run-flat tire can take into account both high-speed performance and zero-pressure durability performance.

Description

Technical Field

[0001] The present application belongs to the technical field of tire manufacturing, and in particular relates to a cap strip winding method and a run-flat tire. Background Art

[0002] With the advancement of automotive technology, tire performance requirements are becoming increasingly stringent, and run-flat tires are no exception. Currently, high-load index and high-speed ratings are a trend in the development of a full range of run-flat tires. However, tire manufacturers face significant challenges in producing high-load, high-speed run-flat tires. High-speed performance and zero-inflation durability are mutually exclusive, making simultaneous improvements difficult.

[0003] The inclusion of a support rubber structure in run-flat tires differentiates them from conventional tires. Wider and thicker support rubber, along with increased thickness at the sidewall, provides strong support for the tire's sidewall at zero air pressure. The wider support rubber, inserted into the shoulder, provides a certain degree of tread rigidity, minimizing lateral deflection at zero air pressure and ensuring zero-air performance. However, excessively wide and thick support rubber can result in poor heat dissipation, impacting high-speed performance. Summary of the Invention

[0004] In view of the deficiencies in the prior art, the present application provides a cap strip winding method and a run-flat tire.

[0005] The technical solutions provided in this application are as follows:

[0006] A method for winding a crown strip comprises the following steps:

[0007] A first shoulder winding step, winding the first shoulder from a distance C from a first side edge of the total width of the cap band to the first side edge of the total width of the cap band, wherein the first shoulder has a three-layer structure;

[0008] a crown winding step, winding two layers of the crown from a distance C from a first side edge of the total width of the crown band to a distance C from a second side edge of the total width of the crown band, wherein the crown has a two-layer structure;

[0009] The second shoulder winding step is to wind three layers of the second shoulder from a distance C from the second side edge of the total width of the cap band to the second side edge of the total width of the cap band, wherein the second shoulder is a three-layer structure.

[0010] In some embodiments of the present application, the first shoulder wrapping step specifically includes:

[0011] Starting at a distance C from the first side edge of the total width of the cap band, the thread is wound flatly toward the first side at a pitch of (a+1) mm to the first side edge of the total width of the cap band, with a winding angle of 360*C / (a+1);

[0012] Wrap the crown band strip around the first side edge of the total width of the crown band strip with a pitch of 0 mm and a wrapping angle of 360°;

[0013] Winding to the second side with a pitch of (a / 2+1) mm to the first side edge of the total width of the crown strip at a distance C, with a winding angle of 360*C / (a / 2+1);

[0014] Where L is the total width of the crown strip, C is the shoulder width, and a is the width of a single crown strip.

[0015] In some embodiments of the present application, the crown winding step specifically includes:

[0016] The thread is wound from the first side edge distance C of the total width of the crown strip to the second side edge distance C of the total width of the crown strip with a pitch of (a / 2+1) mm, and the winding angle is 360*(L-2C) / (a / 2+1).

[0017] In some embodiments of the present application, the second shoulder wrapping step specifically includes:

[0018] Winding from the second side edge of the total width of the crown band at a distance C to the second side edge of the total width of the crown band at a pitch of (a / 2+1) mm, with a winding angle of 360*C / (a / 2+1);

[0019] Wrap the crown band strip around the second side edge of the total width of the crown band strip with a pitch of 0 mm and a wrapping angle of 360°;

[0020] The thread is wound from the second side edge of the total width of the cap band to the first side at a pitch of (a+1) mm to a distance C from the second side edge of the total width of the cap band, and the winding angle is 360*C / (a+1).

[0021] The present application also provides a run-flat tire, the sidewall of which includes, from the inside to the outside, an inner liner, a support rubber, a carcass layer, an apex rubber, a grommet rubber and a sidewall rubber, and the tread includes, from the inside to the outside, the inner liner, the carcass layer, a belt layer, a cap layer and a tread rubber, and the cap layer includes three layers of a first shoulder and a second shoulder and two layers of a crown.

[0022] In some embodiments of the present application, the cap strips of the cap layer are wound according to the following steps:

[0023] Starting at a distance C from the first side edge of the total width of the cap band, the thread is wound flatly toward the first side at a pitch of (a+1) mm to the first side edge of the total width of the cap band, with a winding angle of 360*C / (a+1);

[0024] Wrap the crown band strip around the first side edge of the total width of the crown band strip with a pitch of 0 mm and a wrapping angle of 360°;

[0025] With a pitch of (a / 2+1) mm, it is wound to the second side edge of the total width of the crown strip, and the winding angle is 360*L / (a / 2+1);

[0026] Wrap the crown band strip around the second side edge of the total width of the crown band strip with a pitch of 0 mm and a wrapping angle of 360°;

[0027] Winding from the second side edge of the total width of the cap band to the first side at a pitch of (a+1) mm to a distance C from the second side edge of the total width of the cap band, with a winding angle of 360*C / (a+1);

[0028] Where L is the total width of the crown strip, C is the shoulder width, and a is the width of a single crown strip;

[0029] After winding is completed, three layers of the first shoulder portion and the second shoulder portion and two layers of the crown portion are formed.

[0030] In some embodiments of the present application, the lateral extension position of the supporting glue does not exceed a position 8-15 mm away from the lateral extension end point of the first shoulder or the second shoulder.

[0031] In some embodiments of the present application, the width of the support glue is 60-130 mm, and the thickness at the thickest point is 6-13 mm.

[0032] In some embodiments of the present application, the tire model is 235 / 55ZRF19 105Y / XL, the width of the support rubber is 120 mm, and the thickness at the thickest point is 11.5 mm.

[0033] Compared with the prior art, the present invention has the following advantages:

[0034] The cap strip winding method provided in the present application forms three layers of first shoulders, three layers of second shoulders, and two layers of crown after winding is completed, which can improve the rigidity of the shoulders while ensuring the overall rigidity of the crown. The present application also provides a run-flat tire, in which the cap strip includes three layers of first shoulders and second shoulders and two layers of crown. The reinforced cap strip can enhance the tightening and binding effect of the cap strip on the belt and other materials at high speeds, thereby improving high-speed performance. The run-flat tire can take into account high performance at high load index and high speed levels as well as run-flat performance. In addition, the use of this cap strip winding method can significantly reduce the volume of the support rubber, save costs, achieve lightweight design, reduce rolling resistance, and enhance the core competitiveness of the tire. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a schematic flow chart of a method for winding a crown strip according to one embodiment of the present application;

[0036] Figure 2It is a schematic structural diagram of a run-flat tire in the prior art;

[0037] Figure 3 1 is a schematic structural diagram of a run-flat tire according to an embodiment of the present application;

[0038] Figure 4 1 is a schematic diagram of the winding steps of a method for winding a crown strip according to an embodiment of the present application;

[0039] Figure 5 This is a schematic structural diagram of a support adhesive according to one embodiment of the present application;

[0040] Numbers in the figure: 1, inner liner; 2, support rubber; 3, carcass layer; 4, apex rubber; 5, bead rubber; 6, sidewall rubber; 7, belt layer; 8, cap layer; 81, first shoulder; 82, second shoulder; 83, crown; 9, tread rubber. DETAILED DESCRIPTION

[0041] The technical solution of the present application is described in detail below in conjunction with specific embodiments. However, it should be understood that without further description, the elements, structures and features in one embodiment may also be beneficially combined with other embodiments.

[0042] It is worth noting that although the accompanying drawings may show a specific order of method steps, the order of the steps may vary from that depicted. In addition, two or more steps may be performed simultaneously or partially simultaneously. Such variations will depend on the software and hardware selected and the designer's choice. All such variations are within the scope of this application.

[0043] It is worth noting that the terms "system," "unit," and "module" used herein are a method for distinguishing different components, elements, parts, portions, or assemblies at different levels. However, these terms may be replaced by other expressions that achieve the same purpose.

[0044] The above embodiments are only for describing the preferred embodiments of the present application and are not intended to limit the scope of the present application. Without departing from the spirit of the present application, various modifications and improvements made by ordinary technicians in this field to the technical solution of the present application should fall within the scope of protection determined by the claims of the present application. Figure 3 and Figure 4 The cross-sectional view represents the tire structure, the horizontal direction in the cross-sectional view is called the transverse direction, and the vertical direction in the cross-sectional view is called the vertical direction.

[0045] like Figure 1 As shown, the method for winding the crown strip provided in the first embodiment of the present application includes the following steps:

[0046] S100: a first shoulder winding step, winding the first shoulder from a distance C from a first side edge of the total width of the cap band to the first side edge of the total width of the cap band, wherein the first shoulder has a three-layer structure;

[0047] S200: a crown winding step, winding two layers of the crown from a distance C from a first side edge of the total width of the crown band to a distance C from a second side edge of the total width of the crown band, wherein the crown has a two-layer structure;

[0048] S300: a second shoulder winding step, winding three layers of the second shoulder from a distance C from the second side edge of the total width of the cap band to the second side edge of the total width of the cap band, wherein the second shoulder is a three-layer structure.

[0049] Specifically, if Figure 2 As shown, the first shoulder wrapping step includes:

[0050] S1: Start at a distance C from the first side edge of the total width of the cap band with a pitch of (a+1) mm and wind flatly toward the first side edge of the total width of the cap band. The winding angle is 360*C / (a+1);

[0051] S2: Wrap the crown band strip around the first side edge of the total width of the crown band strip with a pitch of 0 mm and a wrapping angle of 360°;

[0052] S3: Winding to the second side at a pitch of (a / 2+1) mm to the first side edge of the total width of the crown strip at a distance C, with a winding angle of 360*C / (a / 2+1);

[0053] Where L is the total width of the cap band, C is the width of the first and second shoulders, and a is the width of a single cap band. The width of a single cap band is generally around 10-15mm.

[0054] Specifically, the crown winding step includes:

[0055] S4: Wind from the first side edge distance C of the total width of the crown band to the second side edge distance C of the total width of the crown band with a pitch of (a / 2+1) mm, and the winding angle is 360*(L-2C) / (a / 2+1).

[0056] Specifically, if Figure 2 As shown, the second shoulder winding step specifically includes:

[0057] S5: Winding from the second side edge of the total width of the cap band at a distance C to the second side edge of the total width of the cap band at a pitch of (a / 2+1) mm, with a winding angle of 360*C / (a / 2+1);

[0058] S6: Wrap the crown band strip around the second side edge of the total width of the crown band strip with a pitch of 0 mm and a wrapping angle of 360°;

[0059] S7: Wind from the second side edge of the total width of the cap band to the first side at a pitch of (a+1) mm to a distance C from the second side edge of the total width of the cap band, with a winding angle of 360*C / (a+1).

[0060] Several long cap strips are combined into a single cap strip, which is then wound onto a reel to form a cap strip roll. The roll is then unwound by equipment and then wound onto the tire belt. In the above steps, the first shoulder, crown, and second shoulder are wound from beginning to end using a single cap strip. The cap strip needs to be wound continuously during the crown and second shoulder winding steps, so the crown and second shoulder winding processes are continuous. To illustrate the winding of these different parts, they are described separately.

[0061] like Figure 3 The figure shows a schematic diagram of the structure of a run-flat tire in the prior art. It is difficult for the run-flat tire in the prior art to give a balance between high-speed performance and zero-pressure durability. If the supporting rubber is made thicker and the belt layer is strengthened, the sidewalls can be strongly supported vertically and the lateral stiffness of the tread can be increased to ensure zero-pressure performance. However, the thick supporting rubber generates more heat, which is not conducive to high-speed performance. At the same time, the strong centrifugal force caused by the thick supporting rubber and the strong belt layer when driving at high speed will also cause a loss of high-speed performance. Therefore, the second embodiment of the present application provides a run-flat tire that can give a balance between high-speed performance and zero-pressure durability. Figure 4 As shown in the figure, a run-flat tire provided by the present application comprises, from the inside to the outside, an inner liner 1, a support rubber 2, a carcass layer 3, an apex rubber 4, a spur rubber 5, and a sidewall rubber 6. The tread comprises, from the inside to the outside, the inner liner 1, the carcass layer 3, a belt layer 7, a cap layer 8, and a tread rubber 9. The cap layer 8 comprises a first shoulder 81 and a second shoulder 82 of a three-layer structure, and a crown 83 of a two-layer structure. Figure 2 and Figure 3 It can be seen that, specifically, the lateral extension position of the support rubber 2 of the run-flat tire provided by the present application does not exceed a position of 8-15 mm from the lateral extension end point of the first shoulder 81 or the second shoulder 82, that is, the lateral extension position of the support rubber 2 does not exceed Figure 2The position of the middle P line, which is a vertical line located 8 to 15 mm away from the lateral extension endpoint of the first shoulder 81 or the second shoulder 82. The distance between the lateral extension position of the support rubber and the lateral extension endpoint of the first shoulder or the second shoulder is set to ensure a uniform transition of stiffness from the crown to the shoulder, and to prevent the support rubber endpoint from falling into the tread groove. The specific value can be adjusted based on the simulation results. The specific value of this distance can be 8, 9, 10, 11, 12, 13, 14, 15 or any value between 8 and 15. Figure 2 As shown, in the prior art, the lateral extension of the tire's support rubber often exceeds half of the lateral extension length of the shoulder, or even equals the lateral extension length of the shoulder. The run-flat tire provided by this application reduces the amount of support rubber inserted in the shoulder, thereby reducing heat generation and enhancing heat dissipation in the shoulder, thereby improving the tire's high-speed performance.

[0062] like Figure 5 The figure shows the structure of the support glue. The width K of the support glue is 60-130 mm, and the thickness H at the thickest point is 6-13 mm.

[0063] The cap strip of the above-mentioned run-flat tire is wound according to the following steps:

[0064] Starting at a distance C from the first side edge of the total width of the cap band, the thread is wound flatly toward the first side at a pitch of (a+1) mm to the first side edge of the total width of the cap band, with a winding angle of 360*C / (a+1);

[0065] Wrap the crown band strip around the first side edge of the total width of the crown band strip with a pitch of 0 mm and a wrapping angle of 360°;

[0066] With a pitch of (a / 2+1) mm, it is wound to the second side edge of the total width of the crown strip, and the winding angle is 360*L / (a / 2+1);

[0067] Wrap the crown band strip around the second side edge of the total width of the crown band strip with a pitch of 0 mm and a wrapping angle of 360°;

[0068] Winding from the second side edge of the total width of the cap band to the first side at a pitch of (a+1) mm to a distance C from the second side edge of the total width of the cap band, with a winding angle of 360*C / (a+1);

[0069] Where L is the total width of the crown strip, C is the shoulder width, and a is the width of a single crown strip;

[0070] After winding is completed, three layers of first shoulders, three layers of second shoulders and two layers of crown are formed.

[0071] Specifically, the run-flat tire model is 235 / 55ZRF19 105Y / XL, the width of the support rubber is 120 mm, and the thickness at the thickest point is 11.5 mm.

[0072] To test the high-speed performance and zero-pressure durability of the run-flat tire provided by the second embodiment of the present application, a 235 / 55ZRF19 105Y / XL tire (control tire) was used as an example. A conventional cap strip wrapping method was used, with the support rubber having a width of 140 mm and a thickness of 12.5 mm at its thickest point. The 235 / 55ZRF19 105Y / XL run-flat tire (test tire) of the present application had a support rubber width of 120 mm and a thickness of 11.5 mm at its thickest point. Compared to a conventional run-flat tire, the cap strip weighed 0.35 kg more, the support rubber weighed 0.89 kg less, for a total weight reduction of 0.54 kg. Both tires were tested for zero-pressure performance and high-speed performance, and the results are shown in Table 1 below. The zero-pressure performance test methods and conditions were based on GB / T 30196-2013. The high-speed performance test methods and conditions were based on GB / T 4502, Indoor Test Methods for Passenger Car Tire Performance.

[0073]

[0074] It can be seen that the run-flat tire provided by the present application can focus on improving the rigidity of the shoulder while ensuring the overall rigidity of the crown, and can ensure zero-pressure durable performance by combining with thinning and narrowing the support rubber; at the same time, the reduction of the support rubber padding in the shoulder can reduce heat generation and enhance the heat dissipation of the shoulder, thereby improving the tightening and binding effect of the crown strip on the belt layer and other materials at high speeds, thereby improving high-speed performance. That is, the use of the crown strip winding method provided by the present application can achieve a high-performance run-flat tire with a high load index and high speed level.

Claims

1. A high load index and high speed level run-flat tire, wherein the sidewalls include, from the inside to the outside, an inner liner, a support rubber, a carcass layer, an apex rubber, a bead rubber and a sidewall rubber, and the tread includes, from the inside to the outside, the inner liner, the carcass layer, a belt layer, a cap layer and a tread rubber. It is characterized in that The cap layer comprises three layers of first shoulder and second shoulder and two layers of crown; the cap strips of the cap layer are wound according to the following steps: Starting at a distance C from the first side edge of the total width of the crown band strip, the thread is laid flat and wound toward the first side with a pitch of (a+1) mm to the first side edge of the total width of the crown band strip, and the winding angle is 360*C / (a+1); Wrap a circle of the crown band strip on the first side edge of the total width of the crown band strip with a pitch of 0 mm and a winding angle of 360°; Winding to the second side at a pitch of (a / 2+1) mm to the second side edge of the total width of the crown band strip, with a winding angle of 360*L / (a / 2+1); Wrap a circle of the crown band strip on the second side edge of the total width of the crown band strip with a pitch of 0 mm and a winding angle of 360°; Winding from the second side edge of the total width of the cap band strip to the first side at a pitch of (a+1) mm to a distance C from the second side edge of the total width of the cap band strip, with a winding angle of 360*C / (a+1); Where L is the total width of the crown strip, C is the shoulder width, and a is the width of a single crown strip; The first shoulder, the crown and the second shoulder are wound from beginning to end by a crown band; after the winding is completed, three layers of the first shoulder and the second shoulder and two layers of the crown are formed; The lateral extension position of the supporting glue does not exceed a position of 8-15 mm from a lateral extension end point of the first shoulder or the second shoulder; The tire model is 235 / 55ZRF19 105Y / XL, the width of the support rubber is 120 mm, and the thickness at the thickest part is 11.5 mm.

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