A tire having sidwall bearing markings

Abstract

The present disclosure provides a tire comprising a tread portion and sidewall portions (200) on either side of the tread portion. At least one sidewall portion (200) includes a first channel (206) having a set of identical first repeating units (214) and a second channel (208) having a set of identical second repeating units (216), both oriented in a first direction. The second repeating units (216) are inverted and offset with respect to the first repeating units (214). A distance between the first and second repeating units (214, 216) varies throughout a pitch length (P) of 0.2 mm to 1 mm. The distance between the first and second repeating units (214, 216) ranges from 0.1 mm to 6 mm. The first and second channels (206, 208) are located within a marking (202) on the sidewall portion (200) of the tire.

Description

A TIRE HAVING SIDWALL BEARING MARKINGSTECHNICAL FIELD

[0001] The present subject matter relates, in general, to vehicle tires and, particularly but not exclusively, to a tire having a sidewall region.BACKGROUND

[0002] Tires support load of a vehicle and provide for impact handling, drivability, and safety of the vehicle.

[0003] A tire has a crown or center region, a sidewall region on either side of the center region, and beads on either side of the sidewall region. The center region, also known as the tread of the tire, may be understood as a region of the tire formed along a complete circumference of the tire and spanning along a width of the tire, which contacts with a surface during rotation. The beads may be understood as the edges of the tire. The beads contact with a wheel during the mounting of the tire. The sidewall region is a portion of the tire between the center region and the beads of the tire.

[0004] The sidewall region typically displays essential details of the tire, such as tire size, load index, speed rating, manufacturer information, etc. These details are crucial for proper tire selection, maintenance, and replacement.BRIEF DESCRIPTION OF DRAWINGS

[0005] The detailed description is described with reference to the accompanying figures. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the drawings to reference like features and components.

[0006] Fig. 1 illustrates a front view of a conventional sidewall portion of a tire depicting a macro serration on the sidewall portion.

[0007] Fig. 2A illustrates a front view of a sidewall portion of a tire depicting a micro textured pattern within a marking, in accordance with an implementation of the present subject matter.

[0008] Fig. 2B illustrates a top view of the micro textured pattern within the marking on the sidewall portion of the tire, in accordance with an implementation of the present subject matter.

[0009] Fig. 2C illustrates a cross sectional view of a first channel and a second channel depicting multiple internal reflection of light rays, in accordance with an implementation of the present subject matter.

[0010] Fig. 3A illustrates a perspective view of a mold, in accordance with an implementation of the present subject matter.

[0011] Fig. 3B illustrates a front view of the mold, in accordance with an implementation of the present subject matter.

[0012] Fig. 3C illustrates a front exploded view of the mold, in accordance with an implementation of the present subject matter.

[0013] Fig. 3D illustrates the front view of the mold depicting a flatness index, in accordance with an implementation of the present subject matter.

[0014] Fig. 4 illustrates a perspective view of a micro texture pattern formed after the molding process, in accordance with an implementation of the present subject matter.DETAILED DESCRIPTION

[0015] Tires are essential components of vehicles, providing the crucial interface between the vehicle and the road surface. A tire has a crown or center region, a sidewall region on either side of the center region, and beads on either side of the sidewall region. The sidewall region typically includes markings. The markings may include, for example, letters, numbers, symbols, designs etc. Further, the markings may help identify the manufacturer of thetire by including the name of the manufacturer and / or trademark, the size of the tire, and / or other information, such as load index, speed rating, etc. Often, the markings are difficult to read on a black background of sidewall portion of the tire. Tire manufacturers have endeavored to increase the legibility of the markings on the sidewall portion of the tires using numerous techniques.

[0016] One conventional technique for increasing the legibility of the markings on the sidewall portion of the tires involves the use of colored markings. Colored markings (normally markings on the sidewall are colored white) set on the black tire background increase the legibility of the markings. However, the use of colored markings may complicate the manufacturing process. In addition, tires with colored markings tend to require increased maintenance from the tire owner as compared to tires without colored markings.

[0017] Yet another conventional technique for increasing the legibility of the markings on the sidewall portion involves using macro serrations. The macro serrations reflect the light from the sidewall portion, thus, enhance the legibility of the markings on the sidewall portion.

[0018] However, the macro serrations often cause light rays to reflect in a uniform manner resulting in a monochrome appearance across the markings on the sidewall portion. The monochrome appearance leads to the lack of visual contrast between different markings, including brand name, trademarks, and other critical information, on the sidewall of the tire. The lack of visual contrast not only decreases the legibility of the markings but also deteriorates the overall aesthetics of the sidewall portion.

[0019] To elaborate, reference is made to Fig. 1 which illustrates a conventional sidewall portion 100 of a tire depicting a macro serration 104 on the sidewall portion 100.

[0020] As shown in Fig. 1 , the sidewall portion 100 includes markings 102, such as letters, numbers, symbols, designs etc. The markings 102 include a macro serration 104. The macro serration 104 has a uniform configuration across the markings 102 on the sidewall portion 100. The macro serration 104 within the markings 102 on the sidewall portion 100 interacts with light rays 106 in a specific manner. The light rays 106 are represented by arrows, with downward pointing arrows depicting incident light and upward pointing arrows depicting reflected light.

[0021] The amount of light 106 reflected is consistent due to the uniform configuration of macro serrations 104 across the markings 102. Thus, when light 106 hits the surface of the macro serrations 104, it reflects in predictable direction, resulting in a relatively even distribution of reflected light 106. Consequently, the markings 102 appear similar in brightness and tone to the surrounding smooth surface, resulting in the monochrome appearance across the markings 102 on the sidewall portion 100. The monochrome appearance deteriorates the overall aesthetics of the sidewall portion 100 as well as limits the legibility of the markings 102 on the sidewall portion 100, especially when viewed from a distance or under varying lighting conditions.

[0022] Thus, there is a need for a sidewall portion design that suppresses the light reflection on the surface of the sidewall portion which creates contrast and enhances both the legibility of the markings and aesthetic appeal of the sidewall portion, without undue burden of increased maintenance efforts for users.

[0023] To this end, a tire having sidewalls bearing markings is described herein. In an embodiment, the sidewall portion provides to overcome the above-described problems associated with legibility of the markings on the sidewall portion as well as overall aesthetic appeal of the sidewall portion.

[0024] In accordance with an embodiment of the present subject matter, a tire comprises a tread portion and a sidewall portion on either side of the tread portion. The sidewall portion comprises a first channel having a set of first repeating units oriented in a first direction. Each of the first repeating units in the first channel is similar. The sidewall portion further comprises a second channel having of a set of second repeating units oriented in the first direction. Each of the second repeating units in the second channel is similar. Further, the set of second repeating unit in the second channel is inverted and offset with respect to the set of first repeating unit in the first channel. A distance between each repeating unit in the first channel and the second channel is variable throughout a pitch length of a repeating unit. The pitch length of each repeating unit in the first channel and the second channel lies in a range between 0.2 mm to 1 mm. The distance between each repeating unit in the first channel and the second channel lies in a range between 0.1 mm to 0.6 mm. A plurality of pairs of the first channel and second channel are located within a marking such that the area of the sidewall portion withing the marking is covered by such channels.

[0025] The presently disclosed sidewall configuration improves the legibility of the markings on the sidewall of the tire, owing to the set of first repeating units in the first channel and the set of second repeating units in the second channel, wherein the repeating units in the second channel is inverted and offset with respect to the repeating unit in the first channel. The inverted and offset repeating unit in the plurality of pairs of channels allows light to have multiple internal reflection within the respective channels, thereby generating a diffuse surface. Particularly, the multiple internal reflection of light within the channels effectively reduces light reflecting off from the markings on the sidewall portion, resulting in a high contrast appearance on the sidewall of thetire. Further, the high contrast significantly enhances the visual appeal of the sidewall, making the markings on the sidewall more distinctive and aesthetic.

[0026] The above and other features, aspects, and advantages of the subject matter will be better explained with regard to the following description and accompanying figures. It should be noted that the description and figures merely illustrate the principles of the present subject matter along with examples described herein and should not be construed as a limitation to the present subject matter. It is thus understood that various arrangements may be devised that, although not explicitly described or shown herein, embody the principles of the present disclosure. Moreover, all statements herein reciting principles, aspects, and examples thereof, are intended to encompass equivalents thereof. Further, for the sake of simplicity, and without limitation, the same numbers are used throughout the drawings to reference like features and components.

[0027] Fig. 2A illustrates a front view of a sidewall portion 200 of a tire depicting a micro textured pattern 204 within a marking 202, in accordance with an implementation of the present subject matter. Fig. 2B illustrates a top view of the micro textured pattern 204 within the marking 202 on the sidewall portion 200, in accordance with an implementation of the present subject matter. Fig. 2C illustrates a cross sectional view of a first channel 206 and a second channel 208 depicting multiple internal reflection of light rays 212, in accordance with an implementation of the present subject matter. Since Figures 2A-2C illustrate an arrangement relationship of a plurality of elements constituting the micro texture pattern 204 within the marking 202 on the sidewall portion 200, for the sake of ease of explanation, Figures 2A-2C are explained together.

[0028] As shown in Fig. 2A, the sidewall portion 200 includes the marking 202. The marking 202 provides different information about the tire, such asname of the manufacturer and / or trademark, the size of the tire, and / or other information, such as load index, speed rating, etc. The micro textured pattern 204 is formed within the marking 202 on the sidewall portion 200. The micro textured pattern 204 has a specific geometry, with angled surfaces forming a sawtooth pattern and a reverse sawtooth pattern, as will be elaborated subsequently, across the markings 202.

[0029] The sawtooth and the reverse sawtooth pattern is designed to interact with light rays 212 incident on the sidewall portion 200. The light rays 212 are represented by arrows, with downward pointing arrows depicting incident light and upward pointing arrows depicting reflected light. The specific geometry of the micro textured pattern 204 allows fewer light rays 212 being reflected directly back to an observer 210. Consequently, the markings 202 on the sidewall portion 200 to appear distinct in brightness and tone to the surrounding smooth surface, resulting in the markings 202 being legible owing to this contrast.

[0030] As shown in Fig. 2B, the micro textured pattern 204 includes a first channel 206 and a second channel 208. The first channel 206 has a set of first repeating units 214 along the first direction. Similarly, the second channel 208 has a set of second repeating units 216 along the first direction. The first direction is along the surface of the sidewall portion. Further, the first channel 206 and the second channel 208 are arranged in alternate configuration with respect to each other.

[0031] Further, the first channel 206 with the set of first repeating units 214 is bounded by a first edge X1 and a second edge X2. Similarly, the second channel 208 with the set of second repeating units 216 is bounded by a first edge X3 and a second edge X4, such that the first edge X3 of the second repeating units 216 is proximal to the second edge X2 of the first repeating units 214.

[0032] Furthermore, a section EE’ represent an area within the micro texture pattern 204 that includes the first channel 206 and the second channel 208. Along the section EE,’ the first channel 206 has a width wider than that of the second channel 208. This variation in the width creates the sawtooth pattern that allows dissipation of light and provides a high contrast between the marking 202 on the sidewall portion 200.

[0033] In another example embodiment, each of the first repeating units 214 in the first channel 206 may have a sawtooth pattern and each of the second repeating units 216 in the second channel 208 may have a reverse sawtooth pattern. In an alternative embodiment, each of the first repeating units 214 in the first channel 206 may have the reverse sawtooth pattern and each of the second repeating units 216 in the second channel 208 may have the sawtooth pattern.

[0034] In an example embodiment, the sawtooth pattern and the reverse sawtooth pattern may have a pitch length P. The pitch length P is the distance between identical points in two adjacent repeating units in the first channel 206 and the second channel 208. Each repeating unit in the first channel 206 and the second channel 208 has equal pitch length and the distance between the first repeating units 214 in the first channel 206 and the second repeating units 216 in the second channel 208 is variable throughout the pitch length P of each of the repeating units. In an example, the pitch length P may be in range of 0.2 mm to 1 mm.

[0035] As apparent from the example embodiment depicted in Fig. 2B, the distance between second edge X2 of the first channel 206 and the first edge X3 of the second channel 208 may vary throughout the pitch length P. This distance may lie in a range between 0.1 mm to 0.6 mm, and preferably in the range of 0.2 mm to 0.3 mm. Likewise, in another example, the distance between the first edge X1 and the second edge X2 of the first channel 206,and the distance between the first edge X3 and the second edge X4 of the second channel, may vary throughout the pitch length P. This distance may lie in a range between 0.02 mm to 0.6 mm, and preferably in the range of 0.04 mm to 0.2 mm.

[0036] In one example embodiment, the set of first repeating units 214 in the first channel 206 is offset Q with respect to the set of second repeating units 216 in the second channel 208. The offset Q between each repeating units in the first channel 206 and each repeating units in the second channel 208 lies in a range of 30% to 60% of the pitch length P.

[0037] In another example embodiment, a phase lag between each of the first repeating units 214 in the first channel 206 and each of the second repeating units 216 in the second channel 208 lies in a range of 240° to 300°. The phase lag may be defined by relative position of the sawtooth pattern and the reverse sawtooth pattern in the micro textured pattern 204.

[0038] In one example embodiment, a plurality of pairs of the first channel 206 and the second channel 208 may be located within the marking 202 present on the sidewall portion 200. Such plurality of pairs of the first channel 206 and the second channel 208 fill the area within the marking 202 present on the sidewall portion 200. Each letter, symbol etc. constituting the marking 202 may thus be covered by the micro textured pattern 204 comprising the plurality of pairs of the first channel 206 and the second channel 208. Such an arrangement of the micro textured pattern 204, as described above, aids legibility of the marking 202 present on the sidewall portion 200.

[0039] To improve the legibility of the marking 202 on the sidewall portion 200 as shown in Fig. 2C, the specific geometry of the first channel 206 and the second channel 208 is configured to form a near “U” shaped rib section that allows the incident light rays 212 to have multiple internal reflections between the first channel 206 and the second channel 208, hence entrapping asignificant portion of the incident light within the channels. This results in fewer light rays 212 being reflected directly back to the observer 210, thereby providing diffuse surface on the sidewall portion 200 which in turn improves the legibility of the markings 202 on the sidewall portion 200 as well as the aesthetics of sidewall portion 200.

[0040] Fig. 3A illustrates a perspective view of a mold 300 to be used for forming the first channel 206 and the second channel 208, respectively, in accordance with an implementation of the present subject matter. Fig. 3B illustrates a front view of the mold 300, in accordance with an implementation of the present subject matter. Fig. 3C illustrates a front exploded view of the mold 300, in accordance with an implementation of the present subject matter. Fig. 3D illustrates the front view of the mold 300 depicting a flatness index, in accordance with an implementation of the present subject matter. Since Figs. 3A-3D illustrate a different view of the mold 300, for the sake of ease of explanation, Figs. 3A-3D are explained together.

[0041] As shown in Fig. 3A, the mold 300 includes a plurality of first mold channel 302 and a plurality of second mold channel 304. The first mold channel 302 and the second mold channel 304 alternate with respect to each other. Further, the first mold channel 302 is inverted and offset with respect to the second mold channel 304. As will be understood, the mold 300 is used to form the micro texture pattern 204 comprising the plurality of pairs of the first channel 206 and the second channel 208. Upon using the mold 300 to form the micro texture pattern 204, the first mold channel 302 and the second mold channel 304, result in formation of the first channel 206 and the second channel 208 on the molded surface, respectively.

[0042] In an example, the plurality of first mold channels 302 and the second mold channels 304 may be formed in the mold 300 through an engraving process. In an example, laser engraving process may be used tocreate the plurality of first mold channels 302 and the second mold channels 304 in the mold 300.

[0043] As shown in Fig. 3B, the first mold channel 302 includes a first wall 306 and a second wall 308. During the molding process, the first wall 306 interfaces with the first edge X1 of the first channel 206 and the second wall 308 interfaces with the second edge X2 of the first channel 206. Similarly, the second mold channel 304 includes a third wall 310 and a fourth wall 312. The third wall 310 interfaces with the first edge X3 of the second channel 208 and the fourth wall 312 interfaces with the second edge X4 of the second channel 208.

[0044] In one example embodiment, the first mold channel 302 and the second mold channel 304 may have concave radius of curvature. The concave radius of curvature may lie in range of 0.5 mm to 1 mm. In another example embodiment, the first mold channel 302 and the second mold channel 304 may have convex radius of curvature. Further, the first mold channel 302 and the second mold channel 304 have a flat apex.

[0045] As shown in Fig. 3C, a width C between two adjacent walls 306 and 308 of the first mold channel 302 may vary along the length of the mold 300. Similarly, a width E between two adjacent walls 310 and 312 of the second mold channel 304 may vary along the length of the mold 300. The width C and E between two adjacent walls of the first mold channel 302 and the second mold channel 304, respectively may lie in range of 0.02 mm to 0.6 mm.

[0046] In one example, the mold 300 has a mold cavity 314. The mold cavity 314 has a non-uniform width throughout its length. The outer region of the mold cavity 314 has a larger width, whereas the inner region of the mold cavity 314 has a smaller width. A width D and B of the mold cavity 314 varies in range of 0.3 mm to 0.02 mm from outer region to the inner region. In oneexample, a depth F of the mold cavity 314 may lie in range of 0.25 mm to 0.5 mm.

[0047] In an example, the walls of the first mold channel 302 may have a flatness index in a range of 0.1 to 0.2. The flatness index may be given by the following equation: flatness index = (0 / 180)

[0048] As shown in Fig. 3D, 0 is an obtuse angle formed between the tangent to the curvature of the edges of the first wall 306 of the first mold channel 302 at the center T of the arc with the horizontal axis of reference and the flat apex. In another embodiment, the obtuse angle 0 may also be formed between the tangent to the curvature of the third wall 310 of the second mold channel 304 at the center T of the arc with the horizontal axis of reference and the flat apex.

[0049] In one example, the lower flatness index provides a larger radius of the curvature of the first mold channel 302 and the second mold channel 304.

[0050] Fig. 4 illustrates a perspective view of a micro texture pattern 400 formed after the molding process, in accordance with an implementation of the present subject matter.

[0051] As shown in Fig. 4, a micro texture pattern 400 includes a plurality of first channel 402 and a plurality of second channel 404. The first channel 402 is inverted and offset with respect to the second channel 404. Further, the first channel 402 and the second channel 404 are alternate with respect to each other. Since the first channel and the second channel are positioned alternately with respect to each other, the set of first repeating units 214 included in the first channel 206 also alternates with the set of second repeating units 216 included in the second channel 208.

[0052] In one example, the micro texture pattern 400 is same as the micro texture pattern 204.

[0053] In an example embodiment, a jetness index for different designs was measured and compared. The different designs include the micro texture pattern 202 of the present invention, conventional macro serration pattern 102, and a plane surface. The jetness index is the ratio of light incident on the surface to the light reflected back. A smaller jetness index corresponds to a higher contrast. The results of the jetness index for the different design are presented in Table 1.

[0054] The result confirmed that the micro texture pattern 204 of the present invention has least jetness index, thus, the micro texture pattern 204 of the present invention provides a higher contrast, thereby enhancing the legibility of the marking 202 on the sidewall portion 200 as well as improves the aesthetics of the sidewall portion 200. This relatively lower value of jetness index provides a matte surface on the sidewall portion, thereby enhancing the legibility of the marking 202 on the sidewall portion 200 as well as improves the aesthetics of the sidewall portion 200.

[0055] In one example with implementation of present subject matter, the absolute value of jetness index may lie in the range of 14.00 to 16.00.

[0056] The ratio of jetness index of micro texture pattern surface to that of plane surface is in range of 60% to 70%. This provides a matte surface on the sidewall portion, thereby enhancing the legibility of the marking 202 on the sidewall portion 200 as well as improves the aesthetics of the sidewall portion 200.

[0057] Although implementations for improving the contrast and the legibility of the marking on the sidewall portion are described, it is to beunderstood that the present subject matter is not necessarily limited to the specific features described. Rather, the specific features are disclosed as implementations.

Claims

l / We Claim:

1. A tire comprising: a tread portion; a sidewall portion (200) on either side of the tread portion, wherein at least one sidewall portion (200) comprises: a first channel (206) having a set of first repeating units (214) oriented in a first direction, wherein each of the first repeating units (214) in the first channel (206) is similar; a second channel (208) having a set of second repeating units (216) oriented in the first direction, wherein each of the second repeating units (216) in the second channel (208) is similar; wherein each of the second repeating units (216) in the second channel (208) is inverted and offset with respect to each of the first repeating units (214) in the first channel (206); wherein a distance between each of the first repeating units (214) in the first channel (206) and each of the second repeating units (216) in the second channel (208) is variable throughout a pitch length (P) of each of the repeating units (214, 216); wherein the pitch length (P) of each of the repeating units (214, 216) lies in a range between 0.2 mm to 1 mm; wherein the distance between each of the first repeating unit (214) in the first channel (206) and each of the second repeating unit (216) in the second channel (208) lies in a range between 0.1 mm to 0.6 mm; and wherein the first channel (206) and the second channel (208) are located within a marking (202) present on the sidewall portion (200) of the tire.

2. The tire as claimed in claim 1 , wherein the set of first repeating units (214) in the first channel (206) alternates with the set of second repeating units (216) in the second channel (208).

3. The tire as claimed in claim 1 , wherein each of the first repeating units (214) in the first channel (206) has a sawtooth pattern.

4. The tire as claimed in claim 1 , wherein each of the second repeating units (216) in the second channel (208) has a reverse sawtooth pattern.

5. The tire as claimed in claim 1 , wherein the offset (Q) between each of the first repeating units (214) in the first channel (206) and each of the second repeating units (216) in the second channel (208) lies in a range between 30% to 60% of the pitch length (P).

6. The tire as claimed in claim 1 , wherein a phase lag between each of the first repeating units (214) in the first channel (206) and each of the second repeating units (216) in the second channel (208) lies in a range between 240° to 300°.

7. The tire as claimed in claim 1 , wherein the distance between each of the first repeating units (214) in the first channel (206) and each of the second repeating units (216) in the second channel (208) lies in range between 0.02 mm to 0.6 mm.

8. The tire as claimed in claim 1 , wherein a plurality of pairs of the first channel (206) and the second channel (208) are located within the marking (202) present on the sidewall portion (200) of the tire.

9. The tire as claimed in claim 1 , wherein the first channel (206) and the second channel (208) are formed using a mold (300).

10. The tire as claimed in claim 9, wherein the mold (300) comprises a first mold channel (302) and a second mold channel (304), and wherein, the first mold channel (303) and the second mold channel (304) in the mold (300) are formed using a laser engraving process.

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