Up-and-down sipe molded member for improving tire performance and achieving economical mold manufacturing

Abstract

A tire mold and a method of manufacturing a tire mold having a plurality of sipes, each sipe disposed within a tread thickness between opposing surfaces of the tread, and each sipe has a thicker frame portion (40) that meets and extends beyond and into the ground engaging surface of the tire tread and a thinner portion (42) that forms a plurality of protrusions (36) on at least one of the opposite sides of the sipe thickness, the plurality of protrusions being spaced apart, each protrusion has a height not greater than a thickness of the frame portion of the sipe.

Description

Technical Field

[0001] The present invention relates to tire treads, and more particularly to the placement and formation of sipes within tire treads, molds for making tire treads, and methods of making such molds having complex sipe molding member geometries. Background Art

[0002] Sipes are often employed in tire treads. Sipes form very narrow grooves or slits within the thickness of the tire tread and are constructed to close or remain closed in certain circumstances within the footprint during operation of the tire. The footprint refers to the contact area between the tire and the ground surface. In some cases, in order to produce an interlocking effect between opposing tread surfaces between which the sipes are arranged (i.e., between opposing sides of the tread in which the sipes are formed), the opposing sides or opposing surfaces are undulating in both the depth direction and the length direction of the sipes. This interlocking can improve tread wear, but may reduce rolling resistance. More complex undulating laminae that address these problems, such as those found in US11,338,618, result in fragile mold parts that increase the cost and expense of tire manufacturing, making further use of this technology cost-prohibitive, particularly in multi-segment tire molds such as tire puzzle molds. Such complex tire sipe geometries traditionally require a flexible or brittle female mold (used herein to describe a male blank for casting the mold and having the finished geometry) to allow the complex geometry sipe molded component to be released from the female mold when inserted into the mold, which increases expense. Therefore, there is a need to both improve tread wear and reduce rolling resistance while reducing manufacturing expense. Summary of the invention

[0003] Particular embodiments of the present invention include a tire tread having a plurality of sipes and methods for forming the tire tread wherein at least one of the opposing sides of the thickness of the sipe includes a plurality of protrusions.

[0004] A specific embodiment of a tire tread having a plurality of sipes includes a tire tread including a length extending in a length direction, a width extending in a lateral direction, and a thickness extending in a depth direction from an outer ground engaging side of the tread, the length direction being a circumferential direction when the tread is arranged on a tire, the width direction being perpendicular to the length direction, and the thickness direction being perpendicular to both the length direction and the width direction of the tread. The plurality of sipes each have a length extending at least partially in a direction of the length or width of the tread, a height extending at least partially in a direction of the depth of the tread and perpendicular to the length of the tread, and a thickness. Each sipe is arranged between opposing surfaces of the tread within the thickness of the tread. Each sipe has a thicker frame portion (or "thick portion") and a thinner portion, the thinner portion forming a plurality of protrusions on at least one of the opposing sides of the thickness of the sipe, the plurality of protrusions being spaced apart. In some cases, each protrusion has a height no greater than the thickness of the frame portion of the sipe.

[0005] In a specific embodiment, a method for forming a tire tread having a plurality of sipes includes the step of molding each of the plurality of sipes using a sipe molding member. Each sipe molding member has a length configured within the tread to extend at least partially in the direction of the length or width of the tread, a height configured within the tread to extend at least partially in the depth direction of the tread and perpendicular to the length of the tread, and a thickness. Each sipe molding member is arranged between opposing surfaces of the tread within the thickness of the tread. At least one of the opposing sides of the thickness of the sipe molding member includes a plurality of protrusions spaced apart. The method for forming a tire tread having a plurality of sipes also includes removing the sipe molding member and leaving the sipes within the tread. The sipe has a void formed into the sipe molding member and a plurality of protrusions corresponding to the plurality of protrusions arranged along the sipe molding member.

[0006] In other embodiments, a mold component and method for making the same is disclosed for making a tire having a plurality of sipes having a complex geometry.

[0007] These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims.The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present invention and, together with the detailed description, serve to explain the principles of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] A complete and enabling disclosure of the present invention, including the best mode thereof, to one of ordinary skill in the art is set forth in the specification with reference to the accompanying drawings, wherein:

[0009] Figure 1 A perspective view of a tire tread having an embodiment of a sipe according to the invention disclosed herein is provided.

[0010] Figure 2 Provided Figure 1 A close-up perspective view of the tire shown.

[0011] Figure 3 A perspective view of an embodiment of a sipe molding component having a thick frame-forming portion and a thin undulating portion with undulations along the length of the sipe molding component is provided.

[0012] Figure 4 Provided Figure 3 Top view of a sipe molded component.

[0013] Figure 5 Provides along Figure 3 A cross section of the sipe molding component taken along line 5-5 in FIG.

[0014] Figure 6 Provides along Figure 3 A cross section of the sipe molding member taken along line 6-6 in FIG.

[0015] Figure 7 A perspective view of an embodiment of a sipe molding member having a thick frame-forming portion and a thin undulating portion with a curved undulation along the length of the sipe molding member is provided.

[0016] Figure 8 Provided Figure 7 Top view of a sipe molded component.

[0017] Fig. 9 Provides along Figure 7 A cross section of the sipe molding component taken along line 9-9 in FIG.

[0018] Fig.10 Provides along Figure 7 A cross section of the sipe molding component taken along line 10-10.

[0019] Fig.11 A perspective view of an embodiment of a sipe molding member having a thick frame-forming portion and a thin undulating portion is provided.

[0020] Fig.12 Provides along Fig.11 A cross section of the sipe molding member taken along line 12-12 in FIG.

[0021] Fig.13 Provides along Fig.11A cross section of the sipe molding component taken along line 13-14 in FIG.

[0022] Fig.14 A perspective view of a mold section for molding a tire and having an embodiment of a sipe molding member is provided.

[0023] Fig.15 A perspective view of a female mold used to form a mold section for molding a tire and having an embodiment of a sipe molding member is provided.

[0024] Fig.16 The insertion of the sipe molding member into the female mold is shown.

[0025] Fig.17 The casting of molding material for forming a tire mold component into a female mold is shown.

[0026] Fig.18 The separation of the mold part from the female mold is shown with the sipe molding component embedded in the mold part.

[0027] The use of the same or similar reference numbers in different drawings denotes the same or similar features. DETAILED DESCRIPTION

[0028] The present invention includes tire treads, tires including such treads, methods for forming tire treads, molds, and methods for forming molds, wherein any such treads include a sipe pattern having a surface geometry as described herein. For the purpose of describing the present invention, reference will now be made in detail to embodiments and / or methods of the present invention, one or more examples of which are shown in or with the accompanying drawings. Each example is provided as an explanation of the present invention rather than a limitation of the present invention. In fact, it will be clear to those skilled in the art that various modifications and changes can be made in the present invention without departing from the scope or spirit of the present invention. For example, a feature or step described or described as part of an embodiment may be used together with another embodiment or step to produce yet another embodiment or method. Therefore, it is desired that the present invention covers such modifications and changes as if they were within the scope of the appended claims and their equivalents.

[0029] With reference to the tire treads described herein, it will be understood that each such tread includes a length, a width, and a thickness. The length extends in a length direction. Since the tread may be formed with the tire, or formed separately for later installation on the tire, such as during a tire retreading operation, for example, when the tread is arranged on the tire, the length direction of the tread is a circumferential (i.e., annular) direction. The width extends in a lateral direction, which is perpendicular to the length direction, while the thickness extends from the outer ground-engaging side of the tread in a depth direction, which is perpendicular to both the length direction and the width direction of the tread.

[0030] The present invention introduces a surface geometry of sipes that increases surface friction and improves interlocking between opposite sides of the tread, between which the sipes are arranged, while improving release of the tire tread from the mold and increasing the durability of the tire tread mold components responsible for producing the sipe features, while allowing for economical mold manufacturing methods. In turn, wear improvements equivalent to conventional undulating sipes can be achieved while reducing mold wear and tear, reducing downtime and scrapped tires, and reducing the cost of manufacturing each tire mold and tire without significantly reducing rolling resistance. In addition, because the new surface geometry further increases the durability of the sipe molding mold member, a wider sipe molding area along the mold member can be added and / or the thickness of the sipe molding area can be reduced, each of which can result in further improvements in wear without significantly reducing rolling resistance.

[0031] It should be understood that the surface geometries described herein may be applied to any sipe pattern known to those of ordinary skill in the art, or obvious variations thereof. Figure 1 The exemplary embodiment shown shows a partial perspective view of a tire tread 10 having a plurality of tread blocks 12, each of which includes a sipe 14. One sipe 14 is shown in more detail in the partial cross-sectional view of a particular tread block 12, and then in FIG. Figure 2 As shown, the tread 10 includes a plurality of sipes 14, each of which has a length L14 extending at least partially in the direction of the tread length L10 or width W10, a height H14 extending at least partially in the direction of the tread depth T10 and perpendicular to the tread length, and a thickness T14. Figure 1 As best seen in FIG. 1 , each sipe 14 is disposed between opposing sides or surfaces 16 of the tread within the thickness of the tread.

[0032] It should be understood that the sipes can form a flat sipe or a contoured sipe. In other words, the body of the sipe can be flat or contoured. A flat sipe can also be referred to as a straight sipe. A contoured sipe is non-planar in that the thickness extends in the direction of the sipe length and / or height along any desired non-linear path, such as a curved path or an undulating path. In an exemplary embodiment, as Figure 1 to Figure 2 As can be seen in the sipe thickness T14 (forming the bulk of the sipe) varies from a thicker frame portion 15 to an undulating thin portion 17 that undulates back and forth along a first path P1 in the direction of the tread length L10 as the sipe extends in the direction of the sipe height H14, which in the illustrated embodiment is also the direction of the tread depth T10. In at least one embodiment, the thickness of the thin portion may be 0.15 mm to 0.4 mm. In other variations, the first path undulates back and forth in the direction of the tread length L10, while the first path extends in the direction of the sipe length L14, which in the illustrated embodiment would be in the direction of the tread width W10. Of course, because the sipes 14 may be formed in any arrangement within the tread, the sipe length and width may extend, at least partially, in any direction of the tread length or width. Because the undulating thickness is not related to or operates as any surface geometry, the undulating thickness of the sipe may be referred to as the undulating bulk. As noted above, the body of the sipe may be said to be planar or contoured when the sipe is more generally planar or contoured in form.

[0033] The first path can be described as a non-linear undulating path because the first path forms multiple undulations. In the embodiment shown, the undulating path includes a series of line segments to form a stepped or zigzag undulating path, but in other variations, the undulating path can be curved. A frame portion 15 of the sipe having a thickness extending in the length direction of the sipe and measured in the thickness direction is formed by a thickened portion of the sipe surrounding the undulating thin portion 17 of the sipe. The amplitude of the undulation in the height direction H14 of the undulating portion is not greater than the thickness of the frame portion surrounding the undulation. The amplitude of the undulation is measured from the peak of the protrusion in the thickness direction on the first side of the sipe to the adjacent side at the base of the undulation.

[0034] It should be understood that the surface geometry described herein may be applied to any sipe known to a person of ordinary skill in the art, or any obvious variation thereof, and in particular, variations of the sipes described herein, where the sipes (and their thickness or body) may not undulate at all in a particular direction or at a particular location in the sipe, or may undulate in one or more directions. For example, the sipes (and their thickness or body) may undulate back and forth not only when the sipes extend in a particular direction, but the sipes (and their thickness or body) may also undulate back and forth when the sipes extend in another direction. When extending in a second direction, the sipes (and their thickness or body) may be said to undulate along a second path (a second non-linear undulating path) in the second direction. For example, with reference to Figure 3 , the sipe molded member 30 forming the sipe 14 is shown as undulating as the sipe extends in both the direction of the sipe molded member height H30 (via the non-linear undulating path P1) and the direction of the sipe molded member length L30 (via the second stepped undulating path P2 including linear segments). The thin sipe molded portion 42 has a series of undulations 32 in the height direction H30. In this embodiment, the two directions are perpendicular to each other. However, in other embodiments, the two directions may be offset from each other by an angle other than 90 degrees (perpendicular). Note that relative to Figure 3 , the thin sipe molded portion 42 and the thick sipe molded portion 40 of the frame portion 15 responsible for molding the sipes both have undulations along a path extending in the length direction L30 of the sipe molded portion of the sipe molded member. It should also be noted that the amplitude of the undulations of both the thick sipe molded portion 40 and the thin sipe molded portion 42 along the path extending in the length direction L30 may be greater than the thickness of the thick sipe molded portion 40, such as Figure 4 , which shows a front view in the height direction relative to the sipe 30. As long as the undulation extending along the path in the height direction does not have an amplitude greater than the thickness of the thick sipe molded portion 40, this is allowed.

[0035] Figure 5 The figure shows the Figure 4 5-5 of the embodiment. Three protrusions 36 are shown in the cross section, wherein the amplitude measured in the thickness direction T30 of the sipe molding member 30 is not greater than the thickness of the thick sipe molding portion 40 measured in the thickness direction T30 of the sipe molding member. A recessed portion 38 is located opposite to each protrusion 36. The thin sipe molding portion 42 terminates in a teardrop-shaped void forming portion 44 in the height direction H30 of the sipe molding portion. Figure 6 Shown along Figure 46-6 of the embodiment. As can be seen here, some portions of the thin sipe molded portion 42 may be free of undulations. In this particular embodiment, the vertical portion is located between the circular protrusions 36 in the thin sipe molded portion 42 of the sipe molded component 30.

[0036] Figure 7 Another embodiment having non-linear undulations along the length L30 of the sipe molded portion 30 of the mold is depicted. This longitudinally oriented curved undulation 46 along the length of the sipe molded portion has no linear portions except at the end extents, which are longitudinally oriented linear portions 48, such as Figure 8 . The thin sipe molded portion 42 has a stiffener 50 formed by a thickened portion of the thin sipe molded portion. The stiffener 50 may be as thick as the thick sipe molded portion 40, or, as depicted in this embodiment, thinner than the thick sipe molded portion 40 but thicker than the thin sipe molded portion 42. These particular stiffeners 50 are in a position without the protrusion 36 and are oriented in the height direction H30 of the sipe molded member 30. As with the previous embodiment, this sipe molded member 30 embodiment does not have undulations in the sipe height direction H30 that are greater in magnitude than the thick sipe molded portion 40.

[0037] Fig. 9 and Fig.10 The cross-sectional views taken along lines 9-9 and 10-10, respectively, show the cross section of the sipe molding member in the height direction H30. The amplitude A of the undulations formed by the protrusions 36 of the sipe molding member along the path extending in the height direction is smaller than the thickness of the thick sipe molding portion 40 measured in the sipe molding member thickness direction T30.

[0038] Fig.11 Another embodiment is depicted having a thick sipe molded portion 40 having a height measured in the sipe height direction H30 that varies along the sipe length direction L30. The sipe molded member 30 of this embodiment is linear along the length of the sipe, except for the undulations formed by the protrusions 36 in the thin sipe molded portion 42. In this embodiment, the protrusions 36 are positioned along varying heights in the sipe height direction H30, as shown by the slightly lower positioning of the middle three protrusions 36. The stiffeners 50 provide additional durability to the thin sipe molded portion of the sipe molded member 30. Fig.12 and Fig.13 Shown along Fig.11The cross sections taken along lines 12-12 and 13-13 in FIG. 1 respectively show that the amplitude of the undulation in the height direction H30 of the sipe molding member 30 is not greater than the thickness of the thick sipe molding portion 40 of the sipe molding member, as in other embodiments. Fig.11 The protrusions 36 are shown arranged in rows, forming a left pair of rows of four protrusions each, a middle row of three protrusions, and a right pair of rows of four protrusions each. Fig.12 The middle row of protrusions is shown offset from the left and right rows of protrusions so that the rows adjacent to the middle row are offset so that each protrusion in the adjacent row is arranged adjacent to the recess 37 of the adjacent row. In this way, the protrusions are not at the same height and the adjacent rows are offset. In this particular embodiment, the protrusions of adjacent rows are offset by half the distance between adjacent protrusions in the height direction of the sipe molding member.

[0039] The sipe molding member 30 disclosed herein can be used in tire molds, particularly molds composed of multiple mold pieces responsible for forming the tread. Such molds are known in the industry as "jigsaw molds" and are characterized by having a plurality of tiny gaps formed by the separation lines between the individual segments through which gases can escape from the mold during the tire molding process. Fig.14 A single piece tire puzzle mold 60 is shown in FIG. These gaps are intended to have tight tolerances so that gas can escape during the molding process without discharging the rubber mixture. The outer surface of the mold requires few or no vent holes, such as small holes drilled in the mold, which tend to form elongated hair-like tire burrs. Removing the burrs makes the finished product smooth and reduces the need to remove excess rubber after molding that affects the aesthetics of the tire.

[0040] When making a "jigsaw puzzle mold," one method of producing the mold 60 is to produce a mold such as Fig.15 The female mold 80 is shown. The female mold 80 has a slot 82 for receiving the sipe molding member 30 and temporarily holding the sipe molding member in the correct position relative to other surface features of the mold. During the process of manufacturing the tire mold 60, the female mold 80 is created and the sipe molding member 30 that will become part of the mold 60 is inserted into the sipe molding member retaining slot 82, as shown in FIG. Fig.16 shown.

[0041] The molding material 58 (usually metal) used to make the mold 60 is poured or cast into the mold 60. Fig.17The sipe molding member 30 is molded into the female mold 80 shown and allowed to harden. The gap between the slot 82 and the sipe molding member 30 is small enough to prevent the molding material 58 from filling in the undulations of the thin sipe molding portion 42 of the sipe molding member 30. The portion of the sipe molding member 30 extending outside the slot 82 of the female mold 80 is captured by the molding material 58, so that when the mold 60 is removed from the female mold 80, the sipe molding member 30 is held in the correct position in the mold 60, as shown in FIG. Fig.18 shown.

[0042] A plurality of these individual molds 60 are arranged circumferentially as part of a tire mold and form the surface of the tread of the tire.

[0043] The amplitude of the undulation of the sipe molding member 30 in the height direction H14 of the sipe must have an amplitude equal to or less than the thickness of the thick sipe molding portion measured in the thickness direction T14 of the sipe to allow the sipe to be released from the female mold 80 and the mold 60 to be separated from the female mold 80.

[0044] With respect to the surface geometry provided for any desired sipe and thus for one or more of the opposing tread sides or surfaces between which the sipe is arranged and defined, the resulting geometry provides a surface geometry feature including a plurality of protrusions and / or depressions forming a planar or non-planar or contoured surface, much like a textured surface, such that when relative movement between the two sides is attempted during operation of the tire, increased friction is observed on the opposing side of the tread between which the sipe is arranged. When the surface geometry is applied to the sipe, the surface geometry is also applied to the plurality of undulations, or in other words, to the sipe body. It should be understood that the spaced-apart protrusions form gap spaces disposed between the protrusions, which gap spaces are relative to the depressions. Of course, the reverse is also true, wherein the spaced-apart depressions form gap spaces disposed between the depressions, which gap spaces are protrusions relative to the depressions. Thus, the protrusions and depressions are used relative to each other, rather than with respect to how each protrusion and depression is formed along the surface. Additionally, it is noted that a protrusion of the sipe is associated with a corresponding depression on one of the opposing sides or surfaces, and vice versa. In certain embodiments, the surface geometric features are formed such that the surface geometric features arranged on the opposing sides generally interlock, such as, for example, when the opposing sides are mirror images of each other.

[0045] refer to Figure 1 and Figure 2, surface geometric features including a plurality of protrusions 18 and corresponding depressions 20 are shown along one of the opposing sides or surfaces 16 of the tread 10, with the sipes arranged and defined between these opposing sides or surfaces. The plurality of protrusions 18 and depressions 20 are spaced apart along the length L14 and height H14 of the sipes. In the variation shown, the protrusions and depressions are evenly spaced apart, but it should be understood that in other variations, the protrusions and / or depressions may be evenly or unevenly spaced apart as desired. Although the arrangement of the protrusions 18 and depressions 20 is shown as forming a substantially smooth or circularly contoured surface, it is contemplated that more defined protrusions and / or depressions may be provided such that the surface is not smoothly contoured, such as, for example, where the protrusions form a cylinder, rectangle, or pointed cone. In a specific embodiment, Figure 3 The smooth or rounded contoured surface shown includes a plurality of evenly spaced protrusions 36 and depressions 38, appearing to be in the shape of a hemisphere.

[0046] A smooth or rounded profile is also described as extending in two perpendicular directions along an undulating path at a particular location. Figure 3 , Figure 4 , Figure 5 and Figure 6 , the plurality of protrusions 36 of the sipe molded component are spaced from the middle of one protrusion to the middle of an adjacent protrusion, or from peak to peak, and have a height (also referred to as an amplitude). The height or amplitude is measured from the base or bottom of the protrusion. The protrusions and depressions are arranged along an undulating path to form a plurality of undulations having a period of 0.8 mm to 2.0 mm, 1.5 mm to 2.0 mm, or 1.6 mm to 1.8 mm (which is the spacing from the middle of one protrusion to the middle of an adjacent protrusion, or from peak to peak) and an amplitude less than the thick sipe molded portion, in other variations, typically in the range of 0.3 mm to 0.9 mm, or 0.5 mm to 0.7, or as Fig.11 In an embodiment of the present invention, the undulation is shown in Figure 1, having a frame thickness of 0.6 mm. In such embodiments, the undulation is in the thin portion, and the thickness from the first side of the thin portion to the second side of the thin portion is in the range of 0.15 mm to 0.4 mm. In such embodiments, the amplitude measures the distance from the base to the peak along the undulation in a single cycle. It should be understood that the undulation can be formed along the surface without affecting the other side of the sipe, or the sipe thickness can undulate along the undulation path, so that when a protrusion is formed on one side of the sipe, a depression is formed opposite the protrusion on the other side of the sipe. In at least one embodiment, the undulation has a period between 1.0 mm and 2.4 mm.

[0047] It should be understood that any of the sipes described herein can be formed by any known method for forming sipes in a tread. For example, a method for forming a tire tread includes the step of molding each of a plurality of sipes using a sipe molding member. The sipe molding member includes a portion having the same shape as any particular sipe described herein, wherein such portion of the sipe molding member is a solid form of the sipe, which is a void. Each sipe molding member is arranged within the tread thickness, between opposing surfaces or opposing sides of the tread within the tread thickness. The sipe molding member thickness T30 undulates back and forth along a first path P1 as the sipe molding member extends in the direction of the sipe molding member height H30 (or length L30). An additional step of such a method includes removing the sipe molding member, which leaves a sipe remaining within the tread, the sipe having a void formed into the sipe molding member and a plurality of protrusions corresponding to the plurality of protrusions disposed along the sipe molding member.

[0048] It should be understood that the sipe molding member may include any form desired by a skilled artisan for use with any known molding equipment. Figures 3 to 10 As shown in one exemplary embodiment of FIG. 4 , the sipe molding member 30 includes a thick sipe molding portion 40 surrounding at least a portion of a thin sipe molding portion 42. In these embodiments, in addition to the thin portion undulating in the direction of the sipe length and height, both the thick portion and the thin portion include undulations in the direction of the sipe length. In other variations, such as Figure 1 , Figure 2 , Figures 11 to 13 As shown, only the thin portion of the sipe includes the surface undulations discussed herein. Obviously, the thick sipe molded portion is thicker than the thin sipe molded portion. In different variations, the thick molded portion can partially or completely surround the thin sipe molded portion in different variations.

[0049] The relief formed by the protrusions 36, and particularly the relief formed by the rounded protrusions as shown in the embodiment shown herein, has been demonstrated to produce tires with superior wear results. Comparative testing was conducted to compare tires having tread patterns molded using a puzzle mold configuration. Figures 11 to 13 A tire having a sipe pattern as depicted in FIG. 1 was compared to a tire having a plurality of sipe patterns with a smooth surface (no undulations). When compared to a non-undulating sipe pattern over the wear life of the tire, a tire having a sipe pattern as depicted in FIG. Figures 11 to 13Tires with sipes formed from the sipe molding member depicted in 30 exhibited a 10% improvement in wear rate without significant changes in other tire properties. Such improved results are surprising because previous tire molds that achieved such results required undulating sipes that required a more complex molding process that allowed for demolding of the mold and the female mold, or required welding of the sipe molding member 30 into the mold that formed the tire, both of which added additional expense to the mold and the finished product. The use of this technology allows tires produced from economically manufactured puzzle molds to employ complex sipe designs.

[0050] It should be understood that any tread discussed herein may be arranged along a toroidal pneumatic tire, or may be formed separately from the tire as a tire component for later installation on a tire carcass, according to any technique or process known to those of ordinary skill in the art. For example, the tread discussed and referenced herein may be molded with a new original tire, or may be formed as a retreaded tire for later installation on a used tire carcass during a retreading operation. Therefore, when referring to a tire tread, the longitudinal direction of the tire tread is synonymous with the circumferential direction of the tire when the tread is installed on the tire. Similarly, the direction of the tread width is synonymous with the axial direction of the tire or the direction of the tire width when the tread is installed on the tire. Finally, the direction of the tread thickness is synonymous with the radial direction of the tire when the tread is installed on the tire. It should be understood that the tread of the present invention may be adopted by any known tire, which may, for example, include a pneumatic tire or a non-pneumatic tire.

[0051] The selected combinations of aspects of the disclosed technology correspond to a variety of different embodiments of the present invention. It should be noted that each of the exemplary embodiments presented and discussed herein should not imply limitations on the subject matter. Features or steps illustrated or described as part of one embodiment may be used in combination with aspects of another embodiment to produce yet another embodiment. In addition, certain features may be interchangeable with similar devices or features that are not explicitly mentioned that perform the same or similar functions.

[0052] The terms "a", "an" and singular forms of words should be deemed to include the plural forms of the same words, such that these terms mean that one or more of something is provided. The terms "at least one" and "one or more" are used interchangeably. A range described as "between a and b" includes the values ​​of "a" and "b".

[0053] The citation of any document does not admit that the document is prior art with respect to any invention disclosed or claimed herein, nor does it admit that the document, alone or in combination with any other referenced document, teaches, suggests, or discloses any such invention. In addition, to the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this document shall govern.

Claims

1. A tire mold, comprising: A plurality of mold parts, each mold part having: a length of the mold components extending in a lengthwise direction, the lengthwise direction being a circumferential direction when the mold components are arranged to form an assembled tire mold; a mold member width extending in a transverse direction, the transverse direction being perpendicular to the mold member length direction; a mold member thickness extending from an outer tread-forming surface of the mold in a depth direction, the depth direction being perpendicular to both the mold member length direction and the mold member width direction; a plurality of sipe molding members, each sipe molding member having a sipe molding member length extending at least partially in the direction of the mold part length or the mold part width, a sipe molding member height extending at least partially in the direction of the mold part thickness and perpendicular to the length, and a sipe molding member thickness, each sipe molding member extending from a mold part surface in the direction of the mold part thickness, wherein each sipe molding member of the plurality of sipe molding members respectively has a thick sipe molding portion having a thickness and a thin sipe molding portion located within the thick sipe molding portion, the thin sipe molding portion having a thickness less than the thickness of the thick sipe molding portion, wherein at least one of the opposite sides of the sipe molding member is arranged to include a plurality of protrusions located on the thin sipe molding portion, the plurality of protrusions being spaced apart and each of the protrusions forming undulations in a height direction of the sipe molding member, the undulations having a magnitude not greater than the thickness of the thick sipe molding portion, wherein one or more of the opposing sides of the thickness of the sipe molding component comprises a plurality of recessed portions, the plurality of recessed portions being spaced apart and each recessed portion forming undulations in a height direction of the sipe molding component, the undulations having a magnitude no greater than the thickness of the thick sipe molding portion.

2. The tire mold of claim 1, wherein the plurality of protrusions are arranged in rows, wherein adjacent rows are displaced relative to each other such that each protrusion in any row is arranged adjacent to one of the recesses in an adjacent row.

3. The tire mold according to claim 1 or 2, wherein the protrusions and the recesses are formed along the thickness of the sipe, and as the sipe extends in the direction of the sipe height or the sipe length, the thickness also undulates back and forth along a non-linear undulating path, the non-linear undulating path forming a plurality of undulations and having a period of 1.0 mm to 2.4 mm and an amplitude not greater than the thickness of the thick sipe molded portion.

4. The tire mold of any of the above claims, wherein the other of the opposing sides of the sipe thickness comprises a plurality of protrusions spaced apart and each having a height measured no greater than the thickness of the thick sipe molded portion.

5. The tire mold of any one of the above claims, wherein for each of the plurality of sipes, the plurality of protrusions and the plurality of depressions are arranged in an alternating protrusion-depression arrangement along the sipe length and sipe height such that the opposing sides of the tread are arranged in a mating configuration.

6. The tire mold according to any one of the above claims, wherein the thick sipe molded portion thickness is measured in the range of 0.3 mm to 0.9 mm.

7. The tire mold according to any one of the above claims, wherein the thin portion thickness is measured in the range of 0.15 mm to 0.4 mm.

8. A method of producing a tire mold, the method comprising: placing a sipe molding member into the slot in the female mold; placing a molding material in the female mold to form a mold part; removing the mold part from the female mold with the sipe molding member embedded in the mold part; The mold components include: a length of the mold components extending in a lengthwise direction, the lengthwise direction being a circumferential direction when the mold components are arranged to form an assembled tire mold; a mold member width extending in a transverse direction, the transverse direction being perpendicular to the mold member length direction; a mold member thickness extending from an outer tread-forming surface of the mold in a depth direction, the depth direction being perpendicular to both the mold member length direction and the mold member width direction; The sipe molding component comprises: a sipe molding member length extending at least partially in a direction of the mold member length or the mold member width, a sipe molding member height extending at least partially in a direction of the mold member thickness and perpendicular to the sipe molding member length, and a sipe molding member thickness, each sipe molding member extending from a mold member surface in the mold member thickness direction; wherein the sipe molded member has a thick sipe molded portion having a thick sipe molded portion thickness and a thin sipe molded portion located within the thick sipe molded portion, the thin sipe molded portion having a thin sipe molded portion thickness that is less than the thickness of the thick sipe molded portion; wherein at least one of the opposing sides of the sipe molding member is arranged to include a plurality of protrusions located on the thin sipe molding portion, the plurality of protrusions being spaced apart and each forming an undulation in the height direction of the sipe molding member, the undulation having a magnitude not greater than the thickness of the thick sipe molding portion, wherein one or more of the opposing sides of the thickness of the sipe molding member includes a plurality of depressions, the plurality of depressions being spaced apart and each forming an undulation in the height direction of the sipe molding member, the undulation having a magnitude not greater than the thickness of the thick sipe molding portion; wherein the thick sipe molded portion engages with the narrow slot in the female mold such that when the molding material is placed into the female mold, no molding material reaches the thin sipe molded portion.

9. The method of producing a tire mold according to claim 8, wherein the molding material is placed into the mold by casting.

10. The method of producing a tire mold according to claim 8 or 9, wherein the plurality of protrusions are arranged in rows, wherein adjacent rows are shifted relative to each other so that each protrusion in any row is arranged adjacent to one of the recesses in an adjacent row.

11. The method of producing a tire mold according to claims 8 to 10, wherein the protrusions and the recesses are formed along the sipe thickness, and as the sipe extends in the direction of the sipe height or the sipe length, the sipe thickness also undulates back and forth along a non-linear undulating path, the non-linear undulating path forming a plurality of undulations and having a period of 1.0 mm to 2.4 mm and an amplitude not greater than the thickness of the thick sipe molded portion.

12. The method of producing a tire mold according to claims 8 to 10, wherein the other of the opposing sides of the sipe thickness comprises a plurality of protrusions spaced apart and each having a height measured no greater than the thickness of the thick sipe molded portion.

13. The method of producing a tire mold according to claims 8 to 10, wherein for each of the plurality of sipes, the plurality of protrusions and the plurality of recesses are arranged in an alternating protrusion-recess arrangement along the length and height of the sipe such that the opposing sides of the tread are arranged in a mating configuration.

14. The method of producing a tire mold according to claims 8 to 13, wherein the thick sipe molded portion thickness is measured to be in the range of 0.3 mm to 0.9 mm.

15. A method of producing a tire mold according to claims 8 to 13, wherein the thin portion thickness is measured to be in the range of 0.15 mm to 0.4 mm.

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