Vulcanizing bladder suitable for low flat tire
By optimizing the outline size and thickness distribution of the curing bladder, the problem of poor fit between the existing curing bladder and the low-profile tire was solved, and the tire tread thickness uniformity and wear performance were improved.
Patent Information
- Application Number
- CN202422364147.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-25
- Publication Date
- 2025-09-16
- Estimated Expiration
- 2034-09-25
AI Technical Summary
Existing curing bladders cannot fully fit the tread of gradually flattened low-profile tires, resulting in uneven pressure, uneven tire tread thickness, and thus affecting wear performance.
A curing bladder suitable for low-profile tires was designed. By optimizing its profile size and thickness distribution to match the tire's inner shape, the bladder's outer surface was ensured to fit perfectly within the tire's inner lining. Furthermore, by adjusting the thickness and elastic modulus of each part, uniform pressure was applied to improve rubber flow.
The flatness of the tread of the finished tire is improved, the ground contact shape and pressure distribution are improved, and the wear performance of the tire is improved.
Smart Images
Figure CN223340064U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of tire production, in particular to a vulcanizing bladder suitable for low-profile tires. Background Art
[0002] A curing bladder is a hollow, thin-walled rubber product designed to fit within the cavity of a tire to be vulcanized. By increasing the internal pressure of the bladder and working with the vulcanizer to apply pressure to the tire's interior, the vulcanizer is then used to shape and vulcanize the tire. Made of butyl rubber, the bladder offers excellent airtightness, stability at high temperatures, and resistance to a variety of chemicals. During the vulcanization process, the bladder is filled with compressed steam, air, hot water, or an inert gas. These media provide internal heat and pressure, allowing the uncured green tire to fit tightly against the mold surrounding the tread, completing the final shaping and vulcanization process.
[0003] In recent years, with the changes in the market usage environment, vehicle tires have gradually become flatter, and the aspect ratio of low-profile tires is usually less than 70%. In the process of using existing vulcanizing bladders in conjunction with vulcanizing machines to produce low-profile tires, the cavity in the tire lining of the gradually flattened tire gradually changes from a circle to an ellipse, and the shape formed by the existing vulcanizing bladder after being filled is always spherical, which makes it impossible for it to completely fit with its tire lining, thereby causing the existing vulcanizing bladder to apply uneven pressure to the tire lining of the gradually flattened tire, thereby affecting the abnormal flow of rubber during the vulcanization process, resulting in uneven thickness in the tire tread area, and causing the tire tread to be uneven, that is, the cross-sectional thickness of the middle area of the tire tread is greater than the cross-sectional thickness of the area 50%-70% away from the center of the crown, resulting in poor ground contact shape of the low-profile tire under load conditions, and uneven pressure distribution between the crown and the ground, thereby affecting the wear performance of the tire. Utility Model Content
[0004] The utility model aims to solve the problem of uneven tires during the production of low-profile tires using a curing bladder, and provides a curing bladder suitable for low-profile tires. The specific technical solution is as follows:
[0005] The utility model provides a low-profile tire for a tire blank, which includes a tire crown, the inner surface of which is radially inwardly convex, the tire blank also including tire shoulders and sidewalls, and a curing bladder including a curing bladder body. The utility model is characterized in that the curing bladder body includes: a bladder outer surface that is completely in contact with the inner surface of the tire crown; a first straight line p that is parallel to an axial tangent line a at an axial center point of the outer surface of the tire crown, the first straight line p being an axial tangent line at a radial maximum diameter point of the outer surface of the bladder, and a distance G between the first straight line p and a side of the top end of the curing bladder body away from the tire crown, (G max -G min ) / G ave ≤10%, of which G maxIndicates the maximum value of G, G min Indicates the minimum value of G, G ave It represents the average value of G at each point of the crown (11).
[0006] Furthermore, the thickness of the curing bladder body near the tire shoulder is G a , 70% G≤G a ≤G.
[0007] Preferably, the axial width of the tire crown is W1, and the curing bladder body further includes a bladder top that fits the tire crown, and the axial width of the bladder top is W1. ’ , where 80% ≤ W1 ’ / W1≤120%.
[0008] Preferably, the maximum axial width of the sidewall is W2, and the curing bladder body further comprises bladder sidewalls respectively attached to the inner surface of the sidewall, and the axial width of the bladder sidewall corresponding to the position of the maximum axial width of the sidewall is W2. ’ , of which 90% ≤ W2 ’ / W2≤180%.
[0009] Preferably, the diameter of the axial center point of the inner surface of the crown is Φ1, and the diameter of the axial center point of the outer surface of the top of the capsule is Φ1. ’ , where Φ1 ’ =Φ1 / CS, 100%≤CS≤150%.
[0010] Preferably, the curing bladder body further comprises bladder mounting ends arranged at both ends of the bladder sidewall away from the bladder top. In the axial section of the tire embryo, the inner surface circumference of the tire embryo is L1, the radial radius of the toe of the tire embryo is L2, and in the axial section of the curing bladder body, the outer surface circumference of the curing bladder body is L1. ’ The radial radius of the capsule mounting end away from the capsule side wall is L2 ’ , among which L1 ’ =(L1+2*(L2-L2 ’ )) / LS, 100%≤LS≤140%.
[0011] Preferably, the distance between the toe of the embryo and the axial center point of the inner surface of the crown is H1, and the distance between the axial center point of the outer surface of the bladder and the end face of the bladder installation end away from the bladder side wall is H1. ’ , of which 90% ≤ H1 ’ / H1≤150%.
[0012] It can be seen from the above technical solution that the utility model has the following beneficial effects:
[0013] The utility model optimizes the outline size of the curing bladder to improve the axial and radial matching of the curing bladder and the low-profile tire. Secondly, according to the tire shape of the low-profile tire, the thickness of the corresponding part of the curing bladder is adjusted to reduce the unevenness of the tire tread part of the finished tire, improve the ground contact shape, make the tire ground contact pressure distribution more uniform, and thus improve the wear performance of the tire. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 This is a schematic diagram of an embodiment of the present invention being fully fitted to a tire blank;
[0015] Figure 2 for Figure 1 A partial enlarged view of
[0016] Figure 3 Schematic diagram of the same radial cross section of an embodiment of the present invention and a tire blank.
[0017] In the figure: 1. tire embryo; 11. tire crown; 12. tire shoulder; 13. tire side; 14. tire lining; 2. vulcanization bladder body; 21. bladder outer surface; 22. bladder inner surface; 23. bladder top; 24. bladder sidewall; 25. bladder mounting end. DETAILED DESCRIPTION
[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described 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 making creative efforts are within the scope of protection of the present invention.
[0019] In the description of the embodiments of the present invention, it should be noted that the terms "inside", "outside", "upper", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the product of the present invention is usually placed when in use. They are only for the convenience of describing the present invention 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. Therefore, they cannot be understood as a limitation on the present invention.
[0020] like Figure 1As shown, the low-profile tire applicable to the embodiment of the present invention is a tire blank 1 before vulcanization, which includes a tire crown 11. The inner surface of the tire crown 11 bulges radially inward, and the axial ends of the tire crown 11 are respectively connected to two tire shoulders 12, and the radial ends of the two tire shoulders 12 are respectively connected to the sidewalls 13, and the radial ends of the two sidewalls 13 are respectively connected to the tire rings. The inner surface of the tire blank 1 is the tire lining 14, which is completely fitted with the outer surface of the vulcanization bladder body 2, so that the vulcanization bladder body 2 can provide support to the tire blank 1 during the vulcanization process and maintain the shape of the tire blank 1.
[0021] Secondly, the outer surface of the vulcanization bladder body 2 is the bladder outer surface 21, which is completely fitted with the tire lining 14. The inner surface of the vulcanization bladder body 2 is the bladder inner surface 22, which forms an open cavity. The medium is filled in the cavity to increase its pressure, so that the bladder inner surface 22 pushes the bladder outer surface 21 to gradually fit the tire lining 14, so that the bladder outer surface 21 can completely fit the tire lining 14, so that the bladder outer surface 21 can apply force to each point of the tire lining 14, so that the tire blank 1 provides a support surface for the flow of rubber during the vulcanization process. Secondly, the thickness of the vulcanization bladder body 2 is different, and the difficulty of the bladder inner surface 22 pushing the bladder outer surface 21 to deform is different. The thicker the thickness, the greater the elastic coefficient of this section, the more difficult it is to deform, and the smaller the pressure applied to the tire lining 14. The rubber will flow from the place with high pressure to the place with low pressure, so that the part of the tire lining 14 with greater pressure will be concave toward the outer surface of the tire blank 1.
[0022] like Figure 2 As shown, the capsule top 23 forms a first straight line p parallel to the axial tangent a of the axial center point of the outer surface of the tread 11. The first straight line p is the axial tangent of the radial maximum diameter point of the capsule outer surface 21. The distance between the first straight line p and the inner surface of the capsule top 23 is G, (G max -G min ) / G ave ≤10%.
[0023] Specifically, the axial center point of the outer surface of the crown 11 is a point where its axial center plane and the axial section intersect on the outer surface of the crown 11, wherein the axial center plane is a plane perpendicular to the axis and intersecting at the midpoint of the axis, the axial section is a section coinciding with the axis, the axial tangent a is the tangent of the crown 11 when it contacts the ground, and the first straight line p is parallel to it so that the inner surface of the vulcanized crown 11 can be parallel to the axial tangent a, thereby making the inner and outer surfaces of the crown 11 parallel to the ground when the finished tire contacts the ground, thereby improving its wear performance.
[0024] Secondly, the first straight line p is also the axial tangent line of the maximum radial straight line point on the inner surface of the crown 11, G max represents the maximum distance between the first straight line p and the inner surface of the capsule top 23, Gmin represents the minimum distance between the first straight line p and the inner surface of the capsule top 23, G ave represents the average distance between the first straight line p and the inner surface of the capsule top 23, (G max -G min ) / G ave ≤10% indicates the parallelism between the first straight line p and the inner surface of the bladder top 23. The closer the first straight line p is to parallelism with the inner surface of the bladder top 23, the less obvious the protrusions and depressions on the inner surface of the crown 11, resulting in better wear performance of the tire.
[0025] Here, G is the sum of the thickness of the point where the inner surface of the crown 11 protrudes from its maximum radial diameter and the thickness of the capsule tip 23 at that point. Therefore, the more protruding the inner surface of the crown 11 is, the smaller the thickness of the capsule tip 23 at that point is, the smaller its elastic coefficient is, and the easier it is to deform, thereby exerting a greater pressure on the inner surface of the crown 11 at that point. As a result, during the vulcanization process of the tire blank 1, the rubber flows from that point to the surrounding area with less pressure, thereby making the inner surface of the crown 11 at that point closer to the first straight line p. On the contrary, the unvulcanized tire blank 1 The closer the inner surface of a certain point of the tread crown 11 is to the first straight line p, the thicker the top 23 of the bladder at that point is, the greater its elastic coefficient is, and the more difficult it is to deform. As a result, the pressure applied to the inner surface of the tread crown 11 at that point is smaller, so that during the vulcanization process of the tire blank 1, the rubber flows from the surrounding areas with greater pressure to this area, and the inner surface of the tread crown 11 at this area is further away from the first straight line p. Therefore, the rubber flows from the convex part of the inner surface of the tread crown 11 to the concave part, making the inner surface of the tread crown 11 closer to parallel with the first straight line p.
[0026] Furthermore, the thickness of the curing bladder body 2 near the tire shoulder 12 is Ga, and 70% G≤Ga≤G.
[0027] Specifically, 70% G≤Ga≤G makes the thickness of the vulcanization bladder body 2 at the shoulder 12 not greater than the thickness of the vulcanization bladder body 2 at the maximum radial straight line of the inner surface of the crown 11, thereby making the pressure of the vulcanization bladder body 2 at the shoulder 12 on the shoulder 12 not less than the pressure of the vulcanization bladder body 2 at the maximum radial straight line of the inner surface of the crown 11 on the crown 11, thereby making the rubber flow from the shoulder 12 to the crown 11 during the vulcanization process of the tire embryo 1, thereby preventing the rubber of the crown 11 from flowing to the shoulder 12, causing the inner surface of the crown 11 to be concave, making the inner surface of the crown 11 of the finished tire uneven, and causing the shoulder 12 of the finished tire to be too thick, causing serious heat generation during deformation, thereby reducing the performance of the shoulder and reducing the service life of the tire.
[0028] like Figure 3 a and Figure 3 As shown in b, the axial width of the crown 11 is W1, and the axial width of the bladder top 23 is W1’ , where 80% ≤ W1 ’ / W1≤120%, preferably 90%≤W1 ’ / W1≤110%.
[0029] Specifically, during the contact between the curing bladder body 2 and the tire blank 1, the bladder top 23 first contacts the inner surface of the tire crown 11, and the axial center plane of the bladder top 23 always coincides with the axial center plane of the tire crown 11. ’ / W1<80%, the bladder top 23 applies pressure to the inner surface of the crown 11, causing the rubber to flow from the contact area between the bladder top 23 and the crown 11 to the non-contact area between the two and the shoulder 12 during the vulcanization process of the tire 1, exacerbating the problem of the inner surface of the crown 11 concave in the radial direction and increasing the thickness of the shoulder 12, further reducing the wear performance of the finished tire and shortening its service life; when W1 ’ / W1>120%, the axial width of the bladder top 23 is greater than the axial width of the crown 11, so that when the bladder top 23 applies pressure to the inner surface of the crown 11, the bladder top 23 will fold, causing the inner surface of the crown 11 to be folded, resulting in the inner surface quality of the finished tire being unqualified; when 90%≤W1 ’ When / W1≤110%, the area where the top 23 of the capsule applies pressure on the inner surface of the crown 11 can improve the flatness of the inner surface of the crown 11, alleviate its sinking problem, and enable the shoulder 12 of this thickness to generate heat normally during deformation, without enriching heat and causing the performance of the shoulder to deteriorate.
[0030] Furthermore, the maximum axial width of the sidewall 13 is W2, and the curing bladder body 2 further includes a bladder sidewall 24 respectively attached to the inner surface of the sidewall 13, and the axial width of the bladder sidewall 24 corresponding to the position of the maximum axial width of the sidewall 13 is W2. ’ , of which 90% ≤ W2 ’ / W2≤180%, preferably, 110%≤W2 ’ / W2≤160%.
[0031] Specifically, after the top 23 of the bladder is in full contact with the inner surface of the crown 11, the sidewall 24 of the bladder gradually contacts the inner surface of the sidewall 13. ’ When / W2<90%, during the process of the bladder sidewall 24 adhering to the inner surface of the sidewall 13, the gas between the two is limited by the large distance between the two and cannot be fully squeezed out, resulting in air pockets between the bladder sidewall 24 and the sidewall 13, causing the inner surface quality of the sidewall 13 to be unqualified, and the force on the sidewall 13 to be small, thereby causing the rubber to flow from the part with greater force to the sidewall 13, increasing the thickness of the deformation zone of the sidewall 13, and making the deformation zone prone to fatigue damage, thereby reducing the service life of the finished tire; when W2’ When W2>180%, the bladder sidewall 24 is folded when it is attached to the inner surface of the sidewall 13, causing the inner surface of the sidewall 13 to be folded, resulting in the inner surface quality of the finished tire being unqualified; when 110%≤W2 ’ When / W2≤160%, the shape of the bladder sidewall 24 can be closer to the shape of the sidewall 13, increasing the contact area of the bladder sidewall 24 on the inner surface of the sidewall 13 and making the force on the inner surface of the sidewall 13 more uniform.
[0032] Furthermore, the diameter of the axial center point of the inner surface of the crown 11 is Φ1, and the diameter of the axial center point of the outer surface of the capsule top 23 is Φ1. ’ , where Φ1 ’ =Φ1 / CS, 100%≤CS≤150%, preferably, 110%≤CS≤130%.
[0033] Specifically, CS is the expansion rate of the curing bladder body 2 along the radial direction of the tire during the curing process. When CS is less than 100%, the diameter of the outer surface of the bladder top 23 after expansion along the radial direction of the tire is larger than the diameter of the axial center point of the inner surface of the crown 11, causing the outer surface of the bladder top 23 to fold, thereby causing the inner surface of the crown 11 to be folded, resulting in the problem of the inner lining of the tire 14 being unqualified; when CS is greater than 150%, there is a gap between the outer surface of the bladder top 23 and the inner surface of the crown 11, causing the outer surface of the bladder top 23 to be folded, thereby causing the inner lining of the tire 14 to be unqualified; when CS is greater than 150%, there is a gap between the outer surface of the bladder top 23 and the inner surface of the crown 11, causing the outer surface of the bladder top 23 to be folded, thereby causing the inner lining of the tire 14 to be unqualified; when CS is greater than 150%, there is a gap between the outer surface of the bladder top 23 and the inner surface of the crown 11, thereby ... The outer surface of the capsule does not fully fit with the inner surface of the crown 11, resulting in air pockets between the two, which in turn leads to poor tire molding and an uneven inner surface of the tire, affecting the quality and service life of the tire; when 110%≤CS≤130%, the outer surface of the capsule top 23 can fully fit with the inner surface of the crown 11, so that the pressure exerted by the outer surface of the capsule top 23 on the inner surface of the crown 11 can be matched according to the degree of its inward bulge, thereby improving the flow of the rubber and improving the flatness of the inner surface of the crown 11.
[0034] Furthermore, in the axial section of the tire 1, the circumference of the tire lining 14 is L1, the radial radius of the toe of the tire 1 is L2, and in the axial section of the curing bladder body 2, the circumference of the outer surface of the curing bladder body 2 is L1. ’ The radial radius of the intersection of the capsule mounting end 25 away from the end point of the capsule side wall 24 is L2 ’ , among which L1 ’ =(L1+2*(L2-L2 ’ )) / LS, 100%≤LS≤140%, preferably 110%≤LS≤130%.
[0035] Specifically, LS is the expansion of the curing bladder along the circumferential direction of the axial cross section of the tire during the curing process. After the curing bladder body 2 is completely attached to the tire lining 14, the outer surface of the bladder top 23 is attached to the inner surface of the tire crown 11, the outer surface of the bladder sidewall 24 is attached to the inner surface of the tire side 13, and the bladder mounting end 25 is not attached to the inner surface of the tire crown 11. It is installed on the curing machine (existing technology, not shown in the figure), where 2*(L2-L2 ’ ) is the outer surface circumference of the bladder mounting ends 25 on both sides in the axial cross section. When LS < 100%, the outer surface circumference of the bladder sidewalls 24 and the bladder top 23 is greater than the circumference of the tire lining 14, causing the outer surface of the vulcanization bladder body 2 to fold after being fully adhered to the tire lining 14, thereby causing the inner lining of the tire lining 14 to be folded. When LS > 140%, the outer surface circumference of the bladder sidewalls 24 and the bladder top 23 is less than the circumference of the tire lining 14. As a result, during the process of the outer surface of the vulcanization bladder body 2 being adhered to the tire lining 14, the pressure applied by the bladder sidewalls 24 on the inner surface of the tire sidewall 13 is insufficient, thereby causing air pockets to form between the two, affecting the quality and service life of the finished tire. When 110% ≤ LS ≤ 130%, the outer surface of the vulcanization bladder body 2 can be fully adhered to the tire lining 14, and pressure is applied to each point of the tire lining 14, thereby improving the flow of the rubber compound, thereby improving the surface quality of the tire lining 14 and improving the unevenness.
[0036] Furthermore, the distance between the toe of the tire 1 and the axial center point of the inner surface of the tire crown 11 is H1, and the distance between the axial center point of the outer surface 21 of the bladder and the end face of the bladder mounting end 25 away from the bladder side wall 24 is H1. ’ , of which 90% ≤ H1 ’ / H1≤150%, preferably 100%≤H1 ’ / H1≤130%.
[0037] Specifically, when H1 ’ / H1<90%, there is a gap between the outer surface of the bladder tip 23 and the inner surface of the tread 11, so that the outer surface of the bladder tip 23 is not completely in contact with the inner surface of the tread 11, and air pockets are generated between the two, affecting the quality of the finished tire; when H1 ’ / H1>150%, when the outer surface of the bladder top 23 is in contact with the inner surface of the tread crown 11, the outer surface of the bladder sidewall 24 exerts pressure on the inner surface of the sidewall 13, causing folding, which in turn causes the inner surface of the sidewall 13 to be folded, affecting the quality of the tire 14; when 100%≤H1 ’ / H1≤130%, the outer surfaces of the bladder top 23 and the bladder sidewall 24 can completely fit with the inner surface of the tread crown 11, and the pressure applied to the inner surface of the sidewall 13 is evenly distributed, thereby improving the flow of the rubber material.
[0038] Example 1 and Comparative Example 1
[0039] Manufacturing Figure 1 The low-aspect-ratio load-bearing radial tire (315 / 60R22.5) is shown, and the maximum radius difference hmax of the tire lining 14 in the radial direction of the finished tire is tested by the following method. hmax represents the unevenness of the inner surface of the crown 11. The smaller the value, the lower the unevenness of the inner surface of the crown 11, and the higher its flatness.
[0040] Table 1
[0041]
[0042] Table 1 shows the vulcanization bladder body 2 attached to the tire blank 1 and vulcanized to obtain the finished tire. Compared with Example 1, CS increased, LS decreased, and W1 ’ / W1 increases, W2 ’ / W2 reduced, H1 ’ / H1 is reduced, so that the h of Example 1 max Smaller than h of Comparative Example 1 max , that is, the flatness of the tire lining 14 of Example 1 is less than that of the tire lining 14 of Comparative Example 1, that is, the unevenness of the tire lining 14 of Example 1 is reduced, thereby improving the wear performance of the tire.
[0043] Table 2
[0044]
[0045] Table 2 is Figure 1 In the finished tire obtained after vulcanization, the inner surface of the bladder top 23 is parallel to the first straight line p. When the inner surface of the crown 11 bulges inward, the outer surface of the bladder top 23 bulges outward, so that the outer surface of the bladder top 23 is completely fitted with the inner surface of the crown 11. After the tire embryo 1 is vulcanized to obtain the finished tire, the flatness of the inner surface of the crown 11 is lower than that of the comparative example 1, thereby improving the wear performance of the finished tire.
[0046] Although the embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.
[0047] The technology, shape and structure that are not described in detail in this utility model are all well-known technologies.
Claims
1. A curing bladder suitable for a low-profile tire, wherein the low-profile tire is a tire embryo (1), the tire embryo (1) includes a tire crown (11), the inner surface of the tire crown (11) is radially inwardly convex, the tire embryo (1) also includes a tire shoulder (12), a tire sidewall (13), and the curing bladder includes a curing bladder body (2), characterized in that: The vulcanization bladder body (2) comprises: an outer surface (21) of the bladder that is completely in contact with the inner surface of the tread (11); A first straight line p is parallel to the axial tangent line a of the axial center point of the outer surface of the tread (11), and the first straight line p is the axial tangent line of the radial maximum diameter point of the outer surface of the bladder (21). The distance between the first straight line p and the top of the curing bladder body (2) away from the tread (11) is G, (G max -G min ) / G ave ≤10%, of which G max Indicates the maximum value of G, G min Indicates the minimum value of G, G ave It represents the average value of G at each point of the crown (11).
2. The curing bladder according to claim 1, wherein: The thickness of the vulcanizing bladder body (2) near the tire shoulder (12) is G a , 70% G≤G a ≤G.
3. The curing bladder according to claim 2, wherein: The axial width of the tire crown (11) is W1, and the curing bladder body (2) further includes a bladder top (23) in contact with the tire crown (11), and the axial width of the bladder top (23) is W1. ’ , where 80% ≤ W1 ’ / W1≤120%.
4. The curing bladder according to claim 3, wherein: The maximum axial width of the sidewall (13) is W2, and the vulcanization bladder body (2) further includes bladder sidewalls (24) respectively attached to the inner surface of the sidewall (13), and the axial width of the bladder sidewalls (24) corresponding to the position of the maximum axial width of the sidewall (13) is W2. ’ , of which 90% ≤ W2 ’ / W2≤180%.
5. The curing bladder according to claim 4, characterized in that: The diameter of the axial center point of the inner surface of the crown (11) is Φ1, and the diameter of the axial center point of the outer surface of the capsule top (23) is Φ1. ’ , where Φ1 ’ =Φ1 / CS, 100%≤CS≤150%.
6. The curing bladder according to claim 5, characterized in that: The vulcanization bladder body (2) further comprises bladder mounting ends (25) arranged on both ends of the bladder sidewall (24) away from the bladder top. In the axial cross section of the tire embryo (1), the inner surface circumference of the tire embryo (1) is L1, the radial radius of the toe of the tire embryo (1) is L2, and in the axial cross section of the vulcanization bladder body (2), the outer surface circumference of the vulcanization bladder body (2) is L1. ’ The radial radius of the capsule mounting end (25) away from the end point of the capsule side wall is L2 ’ , among which L1 ’ =(L1+2*(L2-L2 ’ )) / LS, 100%≤LS≤140%.
7. The curing bladder according to claim 6, characterized in that: The distance between the toe of the embryo (1) and the axial center point of the inner surface of the crown (11) is H1, and the distance between the axial center point of the outer surface (21) of the bladder and the end face of the bladder mounting end (25) away from the bladder side wall (24) is H1. ’ , of which 90% ≤ H1 ’ / H1≤150%.